xref: /linux/drivers/tty/synclink_gt.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Device driver for Microgate SyncLink GT serial adapters.
3  *
4  * written by Paul Fulghum for Microgate Corporation
5  * paulkf@microgate.com
6  *
7  * Microgate and SyncLink are trademarks of Microgate Corporation
8  *
9  * This code is released under the GNU General Public License (GPL)
10  *
11  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
12  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
13  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
14  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
15  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
16  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
17  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
18  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
19  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
20  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
21  * OF THE POSSIBILITY OF SUCH DAMAGE.
22  */
23 
24 /*
25  * DEBUG OUTPUT DEFINITIONS
26  *
27  * uncomment lines below to enable specific types of debug output
28  *
29  * DBGINFO   information - most verbose output
30  * DBGERR    serious errors
31  * DBGBH     bottom half service routine debugging
32  * DBGISR    interrupt service routine debugging
33  * DBGDATA   output receive and transmit data
34  * DBGTBUF   output transmit DMA buffers and registers
35  * DBGRBUF   output receive DMA buffers and registers
36  */
37 
38 #define DBGINFO(fmt) if (debug_level >= DEBUG_LEVEL_INFO) printk fmt
39 #define DBGERR(fmt) if (debug_level >= DEBUG_LEVEL_ERROR) printk fmt
40 #define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
41 #define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
42 #define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
43 /*#define DBGTBUF(info) dump_tbufs(info)*/
44 /*#define DBGRBUF(info) dump_rbufs(info)*/
45 
46 
47 #include <linux/module.h>
48 #include <linux/errno.h>
49 #include <linux/signal.h>
50 #include <linux/sched.h>
51 #include <linux/timer.h>
52 #include <linux/interrupt.h>
53 #include <linux/pci.h>
54 #include <linux/tty.h>
55 #include <linux/tty_flip.h>
56 #include <linux/serial.h>
57 #include <linux/major.h>
58 #include <linux/string.h>
59 #include <linux/fcntl.h>
60 #include <linux/ptrace.h>
61 #include <linux/ioport.h>
62 #include <linux/mm.h>
63 #include <linux/seq_file.h>
64 #include <linux/slab.h>
65 #include <linux/netdevice.h>
66 #include <linux/vmalloc.h>
67 #include <linux/init.h>
68 #include <linux/delay.h>
69 #include <linux/ioctl.h>
70 #include <linux/termios.h>
71 #include <linux/bitops.h>
72 #include <linux/workqueue.h>
73 #include <linux/hdlc.h>
74 #include <linux/synclink.h>
75 
76 #include <asm/io.h>
77 #include <asm/irq.h>
78 #include <asm/dma.h>
79 #include <asm/types.h>
80 #include <asm/uaccess.h>
81 
82 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_GT_MODULE))
83 #define SYNCLINK_GENERIC_HDLC 1
84 #else
85 #define SYNCLINK_GENERIC_HDLC 0
86 #endif
87 
88 /*
89  * module identification
90  */
91 static char *driver_name     = "SyncLink GT";
92 static char *tty_driver_name = "synclink_gt";
93 static char *tty_dev_prefix  = "ttySLG";
94 MODULE_LICENSE("GPL");
95 #define MGSL_MAGIC 0x5401
96 #define MAX_DEVICES 32
97 
98 static struct pci_device_id pci_table[] = {
99 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
100 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT2_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
101 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT4_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
102 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_AC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
103 	{0,}, /* terminate list */
104 };
105 MODULE_DEVICE_TABLE(pci, pci_table);
106 
107 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
108 static void remove_one(struct pci_dev *dev);
109 static struct pci_driver pci_driver = {
110 	.name		= "synclink_gt",
111 	.id_table	= pci_table,
112 	.probe		= init_one,
113 	.remove		= remove_one,
114 };
115 
116 static bool pci_registered;
117 
118 /*
119  * module configuration and status
120  */
121 static struct slgt_info *slgt_device_list;
122 static int slgt_device_count;
123 
124 static int ttymajor;
125 static int debug_level;
126 static int maxframe[MAX_DEVICES];
127 
128 module_param(ttymajor, int, 0);
129 module_param(debug_level, int, 0);
130 module_param_array(maxframe, int, NULL, 0);
131 
132 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
133 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
134 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
135 
136 /*
137  * tty support and callbacks
138  */
139 static struct tty_driver *serial_driver;
140 
141 static int  open(struct tty_struct *tty, struct file * filp);
142 static void close(struct tty_struct *tty, struct file * filp);
143 static void hangup(struct tty_struct *tty);
144 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios);
145 
146 static int  write(struct tty_struct *tty, const unsigned char *buf, int count);
147 static int put_char(struct tty_struct *tty, unsigned char ch);
148 static void send_xchar(struct tty_struct *tty, char ch);
149 static void wait_until_sent(struct tty_struct *tty, int timeout);
150 static int  write_room(struct tty_struct *tty);
151 static void flush_chars(struct tty_struct *tty);
152 static void flush_buffer(struct tty_struct *tty);
153 static void tx_hold(struct tty_struct *tty);
154 static void tx_release(struct tty_struct *tty);
155 
156 static int  ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
157 static int  chars_in_buffer(struct tty_struct *tty);
158 static void throttle(struct tty_struct * tty);
159 static void unthrottle(struct tty_struct * tty);
160 static int set_break(struct tty_struct *tty, int break_state);
161 
162 /*
163  * generic HDLC support and callbacks
164  */
165 #if SYNCLINK_GENERIC_HDLC
166 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
167 static void hdlcdev_tx_done(struct slgt_info *info);
168 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size);
169 static int  hdlcdev_init(struct slgt_info *info);
170 static void hdlcdev_exit(struct slgt_info *info);
171 #endif
172 
173 
174 /*
175  * device specific structures, macros and functions
176  */
177 
178 #define SLGT_MAX_PORTS 4
179 #define SLGT_REG_SIZE  256
180 
181 /*
182  * conditional wait facility
183  */
184 struct cond_wait {
185 	struct cond_wait *next;
186 	wait_queue_head_t q;
187 	wait_queue_t wait;
188 	unsigned int data;
189 };
190 static void init_cond_wait(struct cond_wait *w, unsigned int data);
191 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w);
192 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *w);
193 static void flush_cond_wait(struct cond_wait **head);
194 
195 /*
196  * DMA buffer descriptor and access macros
197  */
198 struct slgt_desc
199 {
200 	__le16 count;
201 	__le16 status;
202 	__le32 pbuf;  /* physical address of data buffer */
203 	__le32 next;  /* physical address of next descriptor */
204 
205 	/* driver book keeping */
206 	char *buf;          /* virtual  address of data buffer */
207     	unsigned int pdesc; /* physical address of this descriptor */
208 	dma_addr_t buf_dma_addr;
209 	unsigned short buf_count;
210 };
211 
212 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
213 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
214 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
215 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
216 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
217 #define desc_count(a)      (le16_to_cpu((a).count))
218 #define desc_status(a)     (le16_to_cpu((a).status))
219 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
220 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
221 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
222 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
223 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
224 
225 struct _input_signal_events {
226 	int ri_up;
227 	int ri_down;
228 	int dsr_up;
229 	int dsr_down;
230 	int dcd_up;
231 	int dcd_down;
232 	int cts_up;
233 	int cts_down;
234 };
235 
236 /*
237  * device instance data structure
238  */
239 struct slgt_info {
240 	void *if_ptr;		/* General purpose pointer (used by SPPP) */
241 	struct tty_port port;
242 
243 	struct slgt_info *next_device;	/* device list link */
244 
245 	int magic;
246 
247 	char device_name[25];
248 	struct pci_dev *pdev;
249 
250 	int port_count;  /* count of ports on adapter */
251 	int adapter_num; /* adapter instance number */
252 	int port_num;    /* port instance number */
253 
254 	/* array of pointers to port contexts on this adapter */
255 	struct slgt_info *port_array[SLGT_MAX_PORTS];
256 
257 	int			line;		/* tty line instance number */
258 
259 	struct mgsl_icount	icount;
260 
261 	int			timeout;
262 	int			x_char;		/* xon/xoff character */
263 	unsigned int		read_status_mask;
264 	unsigned int 		ignore_status_mask;
265 
266 	wait_queue_head_t	status_event_wait_q;
267 	wait_queue_head_t	event_wait_q;
268 	struct timer_list	tx_timer;
269 	struct timer_list	rx_timer;
270 
271 	unsigned int            gpio_present;
272 	struct cond_wait        *gpio_wait_q;
273 
274 	spinlock_t lock;	/* spinlock for synchronizing with ISR */
275 
276 	struct work_struct task;
277 	u32 pending_bh;
278 	bool bh_requested;
279 	bool bh_running;
280 
281 	int isr_overflow;
282 	bool irq_requested;	/* true if IRQ requested */
283 	bool irq_occurred;	/* for diagnostics use */
284 
285 	/* device configuration */
286 
287 	unsigned int bus_type;
288 	unsigned int irq_level;
289 	unsigned long irq_flags;
290 
291 	unsigned char __iomem * reg_addr;  /* memory mapped registers address */
292 	u32 phys_reg_addr;
293 	bool reg_addr_requested;
294 
295 	MGSL_PARAMS params;       /* communications parameters */
296 	u32 idle_mode;
297 	u32 max_frame_size;       /* as set by device config */
298 
299 	unsigned int rbuf_fill_level;
300 	unsigned int rx_pio;
301 	unsigned int if_mode;
302 	unsigned int base_clock;
303 	unsigned int xsync;
304 	unsigned int xctrl;
305 
306 	/* device status */
307 
308 	bool rx_enabled;
309 	bool rx_restart;
310 
311 	bool tx_enabled;
312 	bool tx_active;
313 
314 	unsigned char signals;    /* serial signal states */
315 	int init_error;  /* initialization error */
316 
317 	unsigned char *tx_buf;
318 	int tx_count;
319 
320 	char *flag_buf;
321 	bool drop_rts_on_tx_done;
322 	struct	_input_signal_events	input_signal_events;
323 
324 	int dcd_chkcount;	/* check counts to prevent */
325 	int cts_chkcount;	/* too many IRQs if a signal */
326 	int dsr_chkcount;	/* is floating */
327 	int ri_chkcount;
328 
329 	char *bufs;		/* virtual address of DMA buffer lists */
330 	dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
331 
332 	unsigned int rbuf_count;
333 	struct slgt_desc *rbufs;
334 	unsigned int rbuf_current;
335 	unsigned int rbuf_index;
336 	unsigned int rbuf_fill_index;
337 	unsigned short rbuf_fill_count;
338 
339 	unsigned int tbuf_count;
340 	struct slgt_desc *tbufs;
341 	unsigned int tbuf_current;
342 	unsigned int tbuf_start;
343 
344 	unsigned char *tmp_rbuf;
345 	unsigned int tmp_rbuf_count;
346 
347 	/* SPPP/Cisco HDLC device parts */
348 
349 	int netcount;
350 	spinlock_t netlock;
351 #if SYNCLINK_GENERIC_HDLC
352 	struct net_device *netdev;
353 #endif
354 
355 };
356 
357 static MGSL_PARAMS default_params = {
358 	.mode            = MGSL_MODE_HDLC,
359 	.loopback        = 0,
360 	.flags           = HDLC_FLAG_UNDERRUN_ABORT15,
361 	.encoding        = HDLC_ENCODING_NRZI_SPACE,
362 	.clock_speed     = 0,
363 	.addr_filter     = 0xff,
364 	.crc_type        = HDLC_CRC_16_CCITT,
365 	.preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
366 	.preamble        = HDLC_PREAMBLE_PATTERN_NONE,
367 	.data_rate       = 9600,
368 	.data_bits       = 8,
369 	.stop_bits       = 1,
370 	.parity          = ASYNC_PARITY_NONE
371 };
372 
373 
374 #define BH_RECEIVE  1
375 #define BH_TRANSMIT 2
376 #define BH_STATUS   4
377 #define IO_PIN_SHUTDOWN_LIMIT 100
378 
379 #define DMABUFSIZE 256
380 #define DESC_LIST_SIZE 4096
381 
382 #define MASK_PARITY  BIT1
383 #define MASK_FRAMING BIT0
384 #define MASK_BREAK   BIT14
385 #define MASK_OVERRUN BIT4
386 
387 #define GSR   0x00 /* global status */
388 #define JCR   0x04 /* JTAG control */
389 #define IODR  0x08 /* GPIO direction */
390 #define IOER  0x0c /* GPIO interrupt enable */
391 #define IOVR  0x10 /* GPIO value */
392 #define IOSR  0x14 /* GPIO interrupt status */
393 #define TDR   0x80 /* tx data */
394 #define RDR   0x80 /* rx data */
395 #define TCR   0x82 /* tx control */
396 #define TIR   0x84 /* tx idle */
397 #define TPR   0x85 /* tx preamble */
398 #define RCR   0x86 /* rx control */
399 #define VCR   0x88 /* V.24 control */
400 #define CCR   0x89 /* clock control */
401 #define BDR   0x8a /* baud divisor */
402 #define SCR   0x8c /* serial control */
403 #define SSR   0x8e /* serial status */
404 #define RDCSR 0x90 /* rx DMA control/status */
405 #define TDCSR 0x94 /* tx DMA control/status */
406 #define RDDAR 0x98 /* rx DMA descriptor address */
407 #define TDDAR 0x9c /* tx DMA descriptor address */
408 #define XSR   0x40 /* extended sync pattern */
409 #define XCR   0x44 /* extended control */
410 
411 #define RXIDLE      BIT14
412 #define RXBREAK     BIT14
413 #define IRQ_TXDATA  BIT13
414 #define IRQ_TXIDLE  BIT12
415 #define IRQ_TXUNDER BIT11 /* HDLC */
416 #define IRQ_RXDATA  BIT10
417 #define IRQ_RXIDLE  BIT9  /* HDLC */
418 #define IRQ_RXBREAK BIT9  /* async */
419 #define IRQ_RXOVER  BIT8
420 #define IRQ_DSR     BIT7
421 #define IRQ_CTS     BIT6
422 #define IRQ_DCD     BIT5
423 #define IRQ_RI      BIT4
424 #define IRQ_ALL     0x3ff0
425 #define IRQ_MASTER  BIT0
426 
427 #define slgt_irq_on(info, mask) \
428 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
429 #define slgt_irq_off(info, mask) \
430 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
431 
432 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
433 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
434 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
435 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
436 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
437 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
438 
439 static void  msc_set_vcr(struct slgt_info *info);
440 
441 static int  startup(struct slgt_info *info);
442 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
443 static void shutdown(struct slgt_info *info);
444 static void program_hw(struct slgt_info *info);
445 static void change_params(struct slgt_info *info);
446 
447 static int  register_test(struct slgt_info *info);
448 static int  irq_test(struct slgt_info *info);
449 static int  loopback_test(struct slgt_info *info);
450 static int  adapter_test(struct slgt_info *info);
451 
452 static void reset_adapter(struct slgt_info *info);
453 static void reset_port(struct slgt_info *info);
454 static void async_mode(struct slgt_info *info);
455 static void sync_mode(struct slgt_info *info);
456 
457 static void rx_stop(struct slgt_info *info);
458 static void rx_start(struct slgt_info *info);
459 static void reset_rbufs(struct slgt_info *info);
460 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
461 static void rdma_reset(struct slgt_info *info);
462 static bool rx_get_frame(struct slgt_info *info);
463 static bool rx_get_buf(struct slgt_info *info);
464 
465 static void tx_start(struct slgt_info *info);
466 static void tx_stop(struct slgt_info *info);
467 static void tx_set_idle(struct slgt_info *info);
468 static unsigned int free_tbuf_count(struct slgt_info *info);
469 static unsigned int tbuf_bytes(struct slgt_info *info);
470 static void reset_tbufs(struct slgt_info *info);
471 static void tdma_reset(struct slgt_info *info);
472 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
473 
474 static void get_signals(struct slgt_info *info);
475 static void set_signals(struct slgt_info *info);
476 static void enable_loopback(struct slgt_info *info);
477 static void set_rate(struct slgt_info *info, u32 data_rate);
478 
479 static int  bh_action(struct slgt_info *info);
480 static void bh_handler(struct work_struct *work);
481 static void bh_transmit(struct slgt_info *info);
482 static void isr_serial(struct slgt_info *info);
483 static void isr_rdma(struct slgt_info *info);
484 static void isr_txeom(struct slgt_info *info, unsigned short status);
485 static void isr_tdma(struct slgt_info *info);
486 
487 static int  alloc_dma_bufs(struct slgt_info *info);
488 static void free_dma_bufs(struct slgt_info *info);
489 static int  alloc_desc(struct slgt_info *info);
490 static void free_desc(struct slgt_info *info);
491 static int  alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count);
492 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count);
493 
494 static int  alloc_tmp_rbuf(struct slgt_info *info);
495 static void free_tmp_rbuf(struct slgt_info *info);
496 
497 static void tx_timeout(unsigned long context);
498 static void rx_timeout(unsigned long context);
499 
500 /*
501  * ioctl handlers
502  */
503 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
504 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
505 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
506 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
507 static int  set_txidle(struct slgt_info *info, int idle_mode);
508 static int  tx_enable(struct slgt_info *info, int enable);
509 static int  tx_abort(struct slgt_info *info);
510 static int  rx_enable(struct slgt_info *info, int enable);
511 static int  modem_input_wait(struct slgt_info *info,int arg);
512 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
513 static int  tiocmget(struct tty_struct *tty);
514 static int  tiocmset(struct tty_struct *tty,
515 				unsigned int set, unsigned int clear);
516 static int set_break(struct tty_struct *tty, int break_state);
517 static int  get_interface(struct slgt_info *info, int __user *if_mode);
518 static int  set_interface(struct slgt_info *info, int if_mode);
519 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
520 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
521 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
522 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
523 static int  set_xsync(struct slgt_info *info, int if_mode);
524 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
525 static int  set_xctrl(struct slgt_info *info, int if_mode);
526 
527 /*
528  * driver functions
529  */
530 static void add_device(struct slgt_info *info);
531 static void device_init(int adapter_num, struct pci_dev *pdev);
532 static int  claim_resources(struct slgt_info *info);
533 static void release_resources(struct slgt_info *info);
534 
535 /*
536  * DEBUG OUTPUT CODE
537  */
538 #ifndef DBGINFO
539 #define DBGINFO(fmt)
540 #endif
541 #ifndef DBGERR
542 #define DBGERR(fmt)
543 #endif
544 #ifndef DBGBH
545 #define DBGBH(fmt)
546 #endif
547 #ifndef DBGISR
548 #define DBGISR(fmt)
549 #endif
550 
551 #ifdef DBGDATA
552 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
553 {
554 	int i;
555 	int linecount;
556 	printk("%s %s data:\n",info->device_name, label);
557 	while(count) {
558 		linecount = (count > 16) ? 16 : count;
559 		for(i=0; i < linecount; i++)
560 			printk("%02X ",(unsigned char)data[i]);
561 		for(;i<17;i++)
562 			printk("   ");
563 		for(i=0;i<linecount;i++) {
564 			if (data[i]>=040 && data[i]<=0176)
565 				printk("%c",data[i]);
566 			else
567 				printk(".");
568 		}
569 		printk("\n");
570 		data  += linecount;
571 		count -= linecount;
572 	}
573 }
574 #else
575 #define DBGDATA(info, buf, size, label)
576 #endif
577 
578 #ifdef DBGTBUF
579 static void dump_tbufs(struct slgt_info *info)
580 {
581 	int i;
582 	printk("tbuf_current=%d\n", info->tbuf_current);
583 	for (i=0 ; i < info->tbuf_count ; i++) {
584 		printk("%d: count=%04X status=%04X\n",
585 			i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
586 	}
587 }
588 #else
589 #define DBGTBUF(info)
590 #endif
591 
592 #ifdef DBGRBUF
593 static void dump_rbufs(struct slgt_info *info)
594 {
595 	int i;
596 	printk("rbuf_current=%d\n", info->rbuf_current);
597 	for (i=0 ; i < info->rbuf_count ; i++) {
598 		printk("%d: count=%04X status=%04X\n",
599 			i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
600 	}
601 }
602 #else
603 #define DBGRBUF(info)
604 #endif
605 
606 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
607 {
608 #ifdef SANITY_CHECK
609 	if (!info) {
610 		printk("null struct slgt_info for (%s) in %s\n", devname, name);
611 		return 1;
612 	}
613 	if (info->magic != MGSL_MAGIC) {
614 		printk("bad magic number struct slgt_info (%s) in %s\n", devname, name);
615 		return 1;
616 	}
617 #else
618 	if (!info)
619 		return 1;
620 #endif
621 	return 0;
622 }
623 
624 /**
625  * line discipline callback wrappers
626  *
627  * The wrappers maintain line discipline references
628  * while calling into the line discipline.
629  *
630  * ldisc_receive_buf  - pass receive data to line discipline
631  */
632 static void ldisc_receive_buf(struct tty_struct *tty,
633 			      const __u8 *data, char *flags, int count)
634 {
635 	struct tty_ldisc *ld;
636 	if (!tty)
637 		return;
638 	ld = tty_ldisc_ref(tty);
639 	if (ld) {
640 		if (ld->ops->receive_buf)
641 			ld->ops->receive_buf(tty, data, flags, count);
642 		tty_ldisc_deref(ld);
643 	}
644 }
645 
646 /* tty callbacks */
647 
648 static int open(struct tty_struct *tty, struct file *filp)
649 {
650 	struct slgt_info *info;
651 	int retval, line;
652 	unsigned long flags;
653 
654 	line = tty->index;
655 	if (line >= slgt_device_count) {
656 		DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
657 		return -ENODEV;
658 	}
659 
660 	info = slgt_device_list;
661 	while(info && info->line != line)
662 		info = info->next_device;
663 	if (sanity_check(info, tty->name, "open"))
664 		return -ENODEV;
665 	if (info->init_error) {
666 		DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
667 		return -ENODEV;
668 	}
669 
670 	tty->driver_data = info;
671 	info->port.tty = tty;
672 
673 	DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
674 
675 	/* If port is closing, signal caller to try again */
676 	if (info->port.flags & ASYNC_CLOSING){
677 		wait_event_interruptible_tty(tty, info->port.close_wait,
678 					     !(info->port.flags & ASYNC_CLOSING));
679 		retval = ((info->port.flags & ASYNC_HUP_NOTIFY) ?
680 			-EAGAIN : -ERESTARTSYS);
681 		goto cleanup;
682 	}
683 
684 	mutex_lock(&info->port.mutex);
685 	info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
686 
687 	spin_lock_irqsave(&info->netlock, flags);
688 	if (info->netcount) {
689 		retval = -EBUSY;
690 		spin_unlock_irqrestore(&info->netlock, flags);
691 		mutex_unlock(&info->port.mutex);
692 		goto cleanup;
693 	}
694 	info->port.count++;
695 	spin_unlock_irqrestore(&info->netlock, flags);
696 
697 	if (info->port.count == 1) {
698 		/* 1st open on this device, init hardware */
699 		retval = startup(info);
700 		if (retval < 0) {
701 			mutex_unlock(&info->port.mutex);
702 			goto cleanup;
703 		}
704 	}
705 	mutex_unlock(&info->port.mutex);
706 	retval = block_til_ready(tty, filp, info);
707 	if (retval) {
708 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
709 		goto cleanup;
710 	}
711 
712 	retval = 0;
713 
714 cleanup:
715 	if (retval) {
716 		if (tty->count == 1)
717 			info->port.tty = NULL; /* tty layer will release tty struct */
718 		if(info->port.count)
719 			info->port.count--;
720 	}
721 
722 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
723 	return retval;
724 }
725 
726 static void close(struct tty_struct *tty, struct file *filp)
727 {
728 	struct slgt_info *info = tty->driver_data;
729 
730 	if (sanity_check(info, tty->name, "close"))
731 		return;
732 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
733 
734 	if (tty_port_close_start(&info->port, tty, filp) == 0)
735 		goto cleanup;
736 
737 	mutex_lock(&info->port.mutex);
738  	if (info->port.flags & ASYNC_INITIALIZED)
739  		wait_until_sent(tty, info->timeout);
740 	flush_buffer(tty);
741 	tty_ldisc_flush(tty);
742 
743 	shutdown(info);
744 	mutex_unlock(&info->port.mutex);
745 
746 	tty_port_close_end(&info->port, tty);
747 	info->port.tty = NULL;
748 cleanup:
749 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
750 }
751 
752 static void hangup(struct tty_struct *tty)
753 {
754 	struct slgt_info *info = tty->driver_data;
755 	unsigned long flags;
756 
757 	if (sanity_check(info, tty->name, "hangup"))
758 		return;
759 	DBGINFO(("%s hangup\n", info->device_name));
760 
761 	flush_buffer(tty);
762 
763 	mutex_lock(&info->port.mutex);
764 	shutdown(info);
765 
766 	spin_lock_irqsave(&info->port.lock, flags);
767 	info->port.count = 0;
768 	info->port.flags &= ~ASYNC_NORMAL_ACTIVE;
769 	info->port.tty = NULL;
770 	spin_unlock_irqrestore(&info->port.lock, flags);
771 	mutex_unlock(&info->port.mutex);
772 
773 	wake_up_interruptible(&info->port.open_wait);
774 }
775 
776 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
777 {
778 	struct slgt_info *info = tty->driver_data;
779 	unsigned long flags;
780 
781 	DBGINFO(("%s set_termios\n", tty->driver->name));
782 
783 	change_params(info);
784 
785 	/* Handle transition to B0 status */
786 	if (old_termios->c_cflag & CBAUD &&
787 	    !(tty->termios.c_cflag & CBAUD)) {
788 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
789 		spin_lock_irqsave(&info->lock,flags);
790 		set_signals(info);
791 		spin_unlock_irqrestore(&info->lock,flags);
792 	}
793 
794 	/* Handle transition away from B0 status */
795 	if (!(old_termios->c_cflag & CBAUD) &&
796 	    tty->termios.c_cflag & CBAUD) {
797 		info->signals |= SerialSignal_DTR;
798  		if (!(tty->termios.c_cflag & CRTSCTS) ||
799  		    !test_bit(TTY_THROTTLED, &tty->flags)) {
800 			info->signals |= SerialSignal_RTS;
801  		}
802 		spin_lock_irqsave(&info->lock,flags);
803 	 	set_signals(info);
804 		spin_unlock_irqrestore(&info->lock,flags);
805 	}
806 
807 	/* Handle turning off CRTSCTS */
808 	if (old_termios->c_cflag & CRTSCTS &&
809 	    !(tty->termios.c_cflag & CRTSCTS)) {
810 		tty->hw_stopped = 0;
811 		tx_release(tty);
812 	}
813 }
814 
815 static void update_tx_timer(struct slgt_info *info)
816 {
817 	/*
818 	 * use worst case speed of 1200bps to calculate transmit timeout
819 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
820 	 */
821 	if (info->params.mode == MGSL_MODE_HDLC) {
822 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
823 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
824 	}
825 }
826 
827 static int write(struct tty_struct *tty,
828 		 const unsigned char *buf, int count)
829 {
830 	int ret = 0;
831 	struct slgt_info *info = tty->driver_data;
832 	unsigned long flags;
833 
834 	if (sanity_check(info, tty->name, "write"))
835 		return -EIO;
836 
837 	DBGINFO(("%s write count=%d\n", info->device_name, count));
838 
839 	if (!info->tx_buf || (count > info->max_frame_size))
840 		return -EIO;
841 
842 	if (!count || tty->stopped || tty->hw_stopped)
843 		return 0;
844 
845 	spin_lock_irqsave(&info->lock, flags);
846 
847 	if (info->tx_count) {
848 		/* send accumulated data from send_char() */
849 		if (!tx_load(info, info->tx_buf, info->tx_count))
850 			goto cleanup;
851 		info->tx_count = 0;
852 	}
853 
854 	if (tx_load(info, buf, count))
855 		ret = count;
856 
857 cleanup:
858 	spin_unlock_irqrestore(&info->lock, flags);
859 	DBGINFO(("%s write rc=%d\n", info->device_name, ret));
860 	return ret;
861 }
862 
863 static int put_char(struct tty_struct *tty, unsigned char ch)
864 {
865 	struct slgt_info *info = tty->driver_data;
866 	unsigned long flags;
867 	int ret = 0;
868 
869 	if (sanity_check(info, tty->name, "put_char"))
870 		return 0;
871 	DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
872 	if (!info->tx_buf)
873 		return 0;
874 	spin_lock_irqsave(&info->lock,flags);
875 	if (info->tx_count < info->max_frame_size) {
876 		info->tx_buf[info->tx_count++] = ch;
877 		ret = 1;
878 	}
879 	spin_unlock_irqrestore(&info->lock,flags);
880 	return ret;
881 }
882 
883 static void send_xchar(struct tty_struct *tty, char ch)
884 {
885 	struct slgt_info *info = tty->driver_data;
886 	unsigned long flags;
887 
888 	if (sanity_check(info, tty->name, "send_xchar"))
889 		return;
890 	DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
891 	info->x_char = ch;
892 	if (ch) {
893 		spin_lock_irqsave(&info->lock,flags);
894 		if (!info->tx_enabled)
895 		 	tx_start(info);
896 		spin_unlock_irqrestore(&info->lock,flags);
897 	}
898 }
899 
900 static void wait_until_sent(struct tty_struct *tty, int timeout)
901 {
902 	struct slgt_info *info = tty->driver_data;
903 	unsigned long orig_jiffies, char_time;
904 
905 	if (!info )
906 		return;
907 	if (sanity_check(info, tty->name, "wait_until_sent"))
908 		return;
909 	DBGINFO(("%s wait_until_sent entry\n", info->device_name));
910 	if (!(info->port.flags & ASYNC_INITIALIZED))
911 		goto exit;
912 
913 	orig_jiffies = jiffies;
914 
915 	/* Set check interval to 1/5 of estimated time to
916 	 * send a character, and make it at least 1. The check
917 	 * interval should also be less than the timeout.
918 	 * Note: use tight timings here to satisfy the NIST-PCTS.
919 	 */
920 
921 	if (info->params.data_rate) {
922 	       	char_time = info->timeout/(32 * 5);
923 		if (!char_time)
924 			char_time++;
925 	} else
926 		char_time = 1;
927 
928 	if (timeout)
929 		char_time = min_t(unsigned long, char_time, timeout);
930 
931 	while (info->tx_active) {
932 		msleep_interruptible(jiffies_to_msecs(char_time));
933 		if (signal_pending(current))
934 			break;
935 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
936 			break;
937 	}
938 exit:
939 	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
940 }
941 
942 static int write_room(struct tty_struct *tty)
943 {
944 	struct slgt_info *info = tty->driver_data;
945 	int ret;
946 
947 	if (sanity_check(info, tty->name, "write_room"))
948 		return 0;
949 	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
950 	DBGINFO(("%s write_room=%d\n", info->device_name, ret));
951 	return ret;
952 }
953 
954 static void flush_chars(struct tty_struct *tty)
955 {
956 	struct slgt_info *info = tty->driver_data;
957 	unsigned long flags;
958 
959 	if (sanity_check(info, tty->name, "flush_chars"))
960 		return;
961 	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
962 
963 	if (info->tx_count <= 0 || tty->stopped ||
964 	    tty->hw_stopped || !info->tx_buf)
965 		return;
966 
967 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
968 
969 	spin_lock_irqsave(&info->lock,flags);
970 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
971 		info->tx_count = 0;
972 	spin_unlock_irqrestore(&info->lock,flags);
973 }
974 
975 static void flush_buffer(struct tty_struct *tty)
976 {
977 	struct slgt_info *info = tty->driver_data;
978 	unsigned long flags;
979 
980 	if (sanity_check(info, tty->name, "flush_buffer"))
981 		return;
982 	DBGINFO(("%s flush_buffer\n", info->device_name));
983 
984 	spin_lock_irqsave(&info->lock, flags);
985 	info->tx_count = 0;
986 	spin_unlock_irqrestore(&info->lock, flags);
987 
988 	tty_wakeup(tty);
989 }
990 
991 /*
992  * throttle (stop) transmitter
993  */
994 static void tx_hold(struct tty_struct *tty)
995 {
996 	struct slgt_info *info = tty->driver_data;
997 	unsigned long flags;
998 
999 	if (sanity_check(info, tty->name, "tx_hold"))
1000 		return;
1001 	DBGINFO(("%s tx_hold\n", info->device_name));
1002 	spin_lock_irqsave(&info->lock,flags);
1003 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
1004 	 	tx_stop(info);
1005 	spin_unlock_irqrestore(&info->lock,flags);
1006 }
1007 
1008 /*
1009  * release (start) transmitter
1010  */
1011 static void tx_release(struct tty_struct *tty)
1012 {
1013 	struct slgt_info *info = tty->driver_data;
1014 	unsigned long flags;
1015 
1016 	if (sanity_check(info, tty->name, "tx_release"))
1017 		return;
1018 	DBGINFO(("%s tx_release\n", info->device_name));
1019 	spin_lock_irqsave(&info->lock, flags);
1020 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
1021 		info->tx_count = 0;
1022 	spin_unlock_irqrestore(&info->lock, flags);
1023 }
1024 
1025 /*
1026  * Service an IOCTL request
1027  *
1028  * Arguments
1029  *
1030  * 	tty	pointer to tty instance data
1031  * 	cmd	IOCTL command code
1032  * 	arg	command argument/context
1033  *
1034  * Return 0 if success, otherwise error code
1035  */
1036 static int ioctl(struct tty_struct *tty,
1037 		 unsigned int cmd, unsigned long arg)
1038 {
1039 	struct slgt_info *info = tty->driver_data;
1040 	void __user *argp = (void __user *)arg;
1041 	int ret;
1042 
1043 	if (sanity_check(info, tty->name, "ioctl"))
1044 		return -ENODEV;
1045 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
1046 
1047 	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1048 	    (cmd != TIOCMIWAIT)) {
1049 		if (tty->flags & (1 << TTY_IO_ERROR))
1050 		    return -EIO;
1051 	}
1052 
1053 	switch (cmd) {
1054 	case MGSL_IOCWAITEVENT:
1055 		return wait_mgsl_event(info, argp);
1056 	case TIOCMIWAIT:
1057 		return modem_input_wait(info,(int)arg);
1058 	case MGSL_IOCSGPIO:
1059 		return set_gpio(info, argp);
1060 	case MGSL_IOCGGPIO:
1061 		return get_gpio(info, argp);
1062 	case MGSL_IOCWAITGPIO:
1063 		return wait_gpio(info, argp);
1064 	case MGSL_IOCGXSYNC:
1065 		return get_xsync(info, argp);
1066 	case MGSL_IOCSXSYNC:
1067 		return set_xsync(info, (int)arg);
1068 	case MGSL_IOCGXCTRL:
1069 		return get_xctrl(info, argp);
1070 	case MGSL_IOCSXCTRL:
1071 		return set_xctrl(info, (int)arg);
1072 	}
1073 	mutex_lock(&info->port.mutex);
1074 	switch (cmd) {
1075 	case MGSL_IOCGPARAMS:
1076 		ret = get_params(info, argp);
1077 		break;
1078 	case MGSL_IOCSPARAMS:
1079 		ret = set_params(info, argp);
1080 		break;
1081 	case MGSL_IOCGTXIDLE:
1082 		ret = get_txidle(info, argp);
1083 		break;
1084 	case MGSL_IOCSTXIDLE:
1085 		ret = set_txidle(info, (int)arg);
1086 		break;
1087 	case MGSL_IOCTXENABLE:
1088 		ret = tx_enable(info, (int)arg);
1089 		break;
1090 	case MGSL_IOCRXENABLE:
1091 		ret = rx_enable(info, (int)arg);
1092 		break;
1093 	case MGSL_IOCTXABORT:
1094 		ret = tx_abort(info);
1095 		break;
1096 	case MGSL_IOCGSTATS:
1097 		ret = get_stats(info, argp);
1098 		break;
1099 	case MGSL_IOCGIF:
1100 		ret = get_interface(info, argp);
1101 		break;
1102 	case MGSL_IOCSIF:
1103 		ret = set_interface(info,(int)arg);
1104 		break;
1105 	default:
1106 		ret = -ENOIOCTLCMD;
1107 	}
1108 	mutex_unlock(&info->port.mutex);
1109 	return ret;
1110 }
1111 
1112 static int get_icount(struct tty_struct *tty,
1113 				struct serial_icounter_struct *icount)
1114 
1115 {
1116 	struct slgt_info *info = tty->driver_data;
1117 	struct mgsl_icount cnow;	/* kernel counter temps */
1118 	unsigned long flags;
1119 
1120 	spin_lock_irqsave(&info->lock,flags);
1121 	cnow = info->icount;
1122 	spin_unlock_irqrestore(&info->lock,flags);
1123 
1124 	icount->cts = cnow.cts;
1125 	icount->dsr = cnow.dsr;
1126 	icount->rng = cnow.rng;
1127 	icount->dcd = cnow.dcd;
1128 	icount->rx = cnow.rx;
1129 	icount->tx = cnow.tx;
1130 	icount->frame = cnow.frame;
1131 	icount->overrun = cnow.overrun;
1132 	icount->parity = cnow.parity;
1133 	icount->brk = cnow.brk;
1134 	icount->buf_overrun = cnow.buf_overrun;
1135 
1136 	return 0;
1137 }
1138 
1139 /*
1140  * support for 32 bit ioctl calls on 64 bit systems
1141  */
1142 #ifdef CONFIG_COMPAT
1143 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1144 {
1145 	struct MGSL_PARAMS32 tmp_params;
1146 
1147 	DBGINFO(("%s get_params32\n", info->device_name));
1148 	memset(&tmp_params, 0, sizeof(tmp_params));
1149 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1150 	tmp_params.loopback        = info->params.loopback;
1151 	tmp_params.flags           = info->params.flags;
1152 	tmp_params.encoding        = info->params.encoding;
1153 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1154 	tmp_params.addr_filter     = info->params.addr_filter;
1155 	tmp_params.crc_type        = info->params.crc_type;
1156 	tmp_params.preamble_length = info->params.preamble_length;
1157 	tmp_params.preamble        = info->params.preamble;
1158 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1159 	tmp_params.data_bits       = info->params.data_bits;
1160 	tmp_params.stop_bits       = info->params.stop_bits;
1161 	tmp_params.parity          = info->params.parity;
1162 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1163 		return -EFAULT;
1164 	return 0;
1165 }
1166 
1167 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1168 {
1169 	struct MGSL_PARAMS32 tmp_params;
1170 
1171 	DBGINFO(("%s set_params32\n", info->device_name));
1172 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1173 		return -EFAULT;
1174 
1175 	spin_lock(&info->lock);
1176 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1177 		info->base_clock = tmp_params.clock_speed;
1178 	} else {
1179 		info->params.mode            = tmp_params.mode;
1180 		info->params.loopback        = tmp_params.loopback;
1181 		info->params.flags           = tmp_params.flags;
1182 		info->params.encoding        = tmp_params.encoding;
1183 		info->params.clock_speed     = tmp_params.clock_speed;
1184 		info->params.addr_filter     = tmp_params.addr_filter;
1185 		info->params.crc_type        = tmp_params.crc_type;
1186 		info->params.preamble_length = tmp_params.preamble_length;
1187 		info->params.preamble        = tmp_params.preamble;
1188 		info->params.data_rate       = tmp_params.data_rate;
1189 		info->params.data_bits       = tmp_params.data_bits;
1190 		info->params.stop_bits       = tmp_params.stop_bits;
1191 		info->params.parity          = tmp_params.parity;
1192 	}
1193 	spin_unlock(&info->lock);
1194 
1195 	program_hw(info);
1196 
1197 	return 0;
1198 }
1199 
1200 static long slgt_compat_ioctl(struct tty_struct *tty,
1201 			 unsigned int cmd, unsigned long arg)
1202 {
1203 	struct slgt_info *info = tty->driver_data;
1204 	int rc = -ENOIOCTLCMD;
1205 
1206 	if (sanity_check(info, tty->name, "compat_ioctl"))
1207 		return -ENODEV;
1208 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1209 
1210 	switch (cmd) {
1211 
1212 	case MGSL_IOCSPARAMS32:
1213 		rc = set_params32(info, compat_ptr(arg));
1214 		break;
1215 
1216 	case MGSL_IOCGPARAMS32:
1217 		rc = get_params32(info, compat_ptr(arg));
1218 		break;
1219 
1220 	case MGSL_IOCGPARAMS:
1221 	case MGSL_IOCSPARAMS:
1222 	case MGSL_IOCGTXIDLE:
1223 	case MGSL_IOCGSTATS:
1224 	case MGSL_IOCWAITEVENT:
1225 	case MGSL_IOCGIF:
1226 	case MGSL_IOCSGPIO:
1227 	case MGSL_IOCGGPIO:
1228 	case MGSL_IOCWAITGPIO:
1229 	case MGSL_IOCGXSYNC:
1230 	case MGSL_IOCGXCTRL:
1231 	case MGSL_IOCSTXIDLE:
1232 	case MGSL_IOCTXENABLE:
1233 	case MGSL_IOCRXENABLE:
1234 	case MGSL_IOCTXABORT:
1235 	case TIOCMIWAIT:
1236 	case MGSL_IOCSIF:
1237 	case MGSL_IOCSXSYNC:
1238 	case MGSL_IOCSXCTRL:
1239 		rc = ioctl(tty, cmd, arg);
1240 		break;
1241 	}
1242 
1243 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1244 	return rc;
1245 }
1246 #else
1247 #define slgt_compat_ioctl NULL
1248 #endif /* ifdef CONFIG_COMPAT */
1249 
1250 /*
1251  * proc fs support
1252  */
1253 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1254 {
1255 	char stat_buf[30];
1256 	unsigned long flags;
1257 
1258 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1259 		      info->device_name, info->phys_reg_addr,
1260 		      info->irq_level, info->max_frame_size);
1261 
1262 	/* output current serial signal states */
1263 	spin_lock_irqsave(&info->lock,flags);
1264 	get_signals(info);
1265 	spin_unlock_irqrestore(&info->lock,flags);
1266 
1267 	stat_buf[0] = 0;
1268 	stat_buf[1] = 0;
1269 	if (info->signals & SerialSignal_RTS)
1270 		strcat(stat_buf, "|RTS");
1271 	if (info->signals & SerialSignal_CTS)
1272 		strcat(stat_buf, "|CTS");
1273 	if (info->signals & SerialSignal_DTR)
1274 		strcat(stat_buf, "|DTR");
1275 	if (info->signals & SerialSignal_DSR)
1276 		strcat(stat_buf, "|DSR");
1277 	if (info->signals & SerialSignal_DCD)
1278 		strcat(stat_buf, "|CD");
1279 	if (info->signals & SerialSignal_RI)
1280 		strcat(stat_buf, "|RI");
1281 
1282 	if (info->params.mode != MGSL_MODE_ASYNC) {
1283 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1284 			       info->icount.txok, info->icount.rxok);
1285 		if (info->icount.txunder)
1286 			seq_printf(m, " txunder:%d", info->icount.txunder);
1287 		if (info->icount.txabort)
1288 			seq_printf(m, " txabort:%d", info->icount.txabort);
1289 		if (info->icount.rxshort)
1290 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1291 		if (info->icount.rxlong)
1292 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1293 		if (info->icount.rxover)
1294 			seq_printf(m, " rxover:%d", info->icount.rxover);
1295 		if (info->icount.rxcrc)
1296 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1297 	} else {
1298 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1299 			       info->icount.tx, info->icount.rx);
1300 		if (info->icount.frame)
1301 			seq_printf(m, " fe:%d", info->icount.frame);
1302 		if (info->icount.parity)
1303 			seq_printf(m, " pe:%d", info->icount.parity);
1304 		if (info->icount.brk)
1305 			seq_printf(m, " brk:%d", info->icount.brk);
1306 		if (info->icount.overrun)
1307 			seq_printf(m, " oe:%d", info->icount.overrun);
1308 	}
1309 
1310 	/* Append serial signal status to end */
1311 	seq_printf(m, " %s\n", stat_buf+1);
1312 
1313 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1314 		       info->tx_active,info->bh_requested,info->bh_running,
1315 		       info->pending_bh);
1316 }
1317 
1318 /* Called to print information about devices
1319  */
1320 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1321 {
1322 	struct slgt_info *info;
1323 
1324 	seq_puts(m, "synclink_gt driver\n");
1325 
1326 	info = slgt_device_list;
1327 	while( info ) {
1328 		line_info(m, info);
1329 		info = info->next_device;
1330 	}
1331 	return 0;
1332 }
1333 
1334 static int synclink_gt_proc_open(struct inode *inode, struct file *file)
1335 {
1336 	return single_open(file, synclink_gt_proc_show, NULL);
1337 }
1338 
1339 static const struct file_operations synclink_gt_proc_fops = {
1340 	.owner		= THIS_MODULE,
1341 	.open		= synclink_gt_proc_open,
1342 	.read		= seq_read,
1343 	.llseek		= seq_lseek,
1344 	.release	= single_release,
1345 };
1346 
1347 /*
1348  * return count of bytes in transmit buffer
1349  */
1350 static int chars_in_buffer(struct tty_struct *tty)
1351 {
1352 	struct slgt_info *info = tty->driver_data;
1353 	int count;
1354 	if (sanity_check(info, tty->name, "chars_in_buffer"))
1355 		return 0;
1356 	count = tbuf_bytes(info);
1357 	DBGINFO(("%s chars_in_buffer()=%d\n", info->device_name, count));
1358 	return count;
1359 }
1360 
1361 /*
1362  * signal remote device to throttle send data (our receive data)
1363  */
1364 static void throttle(struct tty_struct * tty)
1365 {
1366 	struct slgt_info *info = tty->driver_data;
1367 	unsigned long flags;
1368 
1369 	if (sanity_check(info, tty->name, "throttle"))
1370 		return;
1371 	DBGINFO(("%s throttle\n", info->device_name));
1372 	if (I_IXOFF(tty))
1373 		send_xchar(tty, STOP_CHAR(tty));
1374  	if (tty->termios.c_cflag & CRTSCTS) {
1375 		spin_lock_irqsave(&info->lock,flags);
1376 		info->signals &= ~SerialSignal_RTS;
1377 	 	set_signals(info);
1378 		spin_unlock_irqrestore(&info->lock,flags);
1379 	}
1380 }
1381 
1382 /*
1383  * signal remote device to stop throttling send data (our receive data)
1384  */
1385 static void unthrottle(struct tty_struct * tty)
1386 {
1387 	struct slgt_info *info = tty->driver_data;
1388 	unsigned long flags;
1389 
1390 	if (sanity_check(info, tty->name, "unthrottle"))
1391 		return;
1392 	DBGINFO(("%s unthrottle\n", info->device_name));
1393 	if (I_IXOFF(tty)) {
1394 		if (info->x_char)
1395 			info->x_char = 0;
1396 		else
1397 			send_xchar(tty, START_CHAR(tty));
1398 	}
1399  	if (tty->termios.c_cflag & CRTSCTS) {
1400 		spin_lock_irqsave(&info->lock,flags);
1401 		info->signals |= SerialSignal_RTS;
1402 	 	set_signals(info);
1403 		spin_unlock_irqrestore(&info->lock,flags);
1404 	}
1405 }
1406 
1407 /*
1408  * set or clear transmit break condition
1409  * break_state	-1=set break condition, 0=clear
1410  */
1411 static int set_break(struct tty_struct *tty, int break_state)
1412 {
1413 	struct slgt_info *info = tty->driver_data;
1414 	unsigned short value;
1415 	unsigned long flags;
1416 
1417 	if (sanity_check(info, tty->name, "set_break"))
1418 		return -EINVAL;
1419 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1420 
1421 	spin_lock_irqsave(&info->lock,flags);
1422 	value = rd_reg16(info, TCR);
1423  	if (break_state == -1)
1424 		value |= BIT6;
1425 	else
1426 		value &= ~BIT6;
1427 	wr_reg16(info, TCR, value);
1428 	spin_unlock_irqrestore(&info->lock,flags);
1429 	return 0;
1430 }
1431 
1432 #if SYNCLINK_GENERIC_HDLC
1433 
1434 /**
1435  * called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1436  * set encoding and frame check sequence (FCS) options
1437  *
1438  * dev       pointer to network device structure
1439  * encoding  serial encoding setting
1440  * parity    FCS setting
1441  *
1442  * returns 0 if success, otherwise error code
1443  */
1444 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1445 			  unsigned short parity)
1446 {
1447 	struct slgt_info *info = dev_to_port(dev);
1448 	unsigned char  new_encoding;
1449 	unsigned short new_crctype;
1450 
1451 	/* return error if TTY interface open */
1452 	if (info->port.count)
1453 		return -EBUSY;
1454 
1455 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1456 
1457 	switch (encoding)
1458 	{
1459 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1460 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1461 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1462 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1463 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1464 	default: return -EINVAL;
1465 	}
1466 
1467 	switch (parity)
1468 	{
1469 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1470 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1471 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1472 	default: return -EINVAL;
1473 	}
1474 
1475 	info->params.encoding = new_encoding;
1476 	info->params.crc_type = new_crctype;
1477 
1478 	/* if network interface up, reprogram hardware */
1479 	if (info->netcount)
1480 		program_hw(info);
1481 
1482 	return 0;
1483 }
1484 
1485 /**
1486  * called by generic HDLC layer to send frame
1487  *
1488  * skb  socket buffer containing HDLC frame
1489  * dev  pointer to network device structure
1490  */
1491 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1492 				      struct net_device *dev)
1493 {
1494 	struct slgt_info *info = dev_to_port(dev);
1495 	unsigned long flags;
1496 
1497 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1498 
1499 	if (!skb->len)
1500 		return NETDEV_TX_OK;
1501 
1502 	/* stop sending until this frame completes */
1503 	netif_stop_queue(dev);
1504 
1505 	/* update network statistics */
1506 	dev->stats.tx_packets++;
1507 	dev->stats.tx_bytes += skb->len;
1508 
1509 	/* save start time for transmit timeout detection */
1510 	dev->trans_start = jiffies;
1511 
1512 	spin_lock_irqsave(&info->lock, flags);
1513 	tx_load(info, skb->data, skb->len);
1514 	spin_unlock_irqrestore(&info->lock, flags);
1515 
1516 	/* done with socket buffer, so free it */
1517 	dev_kfree_skb(skb);
1518 
1519 	return NETDEV_TX_OK;
1520 }
1521 
1522 /**
1523  * called by network layer when interface enabled
1524  * claim resources and initialize hardware
1525  *
1526  * dev  pointer to network device structure
1527  *
1528  * returns 0 if success, otherwise error code
1529  */
1530 static int hdlcdev_open(struct net_device *dev)
1531 {
1532 	struct slgt_info *info = dev_to_port(dev);
1533 	int rc;
1534 	unsigned long flags;
1535 
1536 	if (!try_module_get(THIS_MODULE))
1537 		return -EBUSY;
1538 
1539 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1540 
1541 	/* generic HDLC layer open processing */
1542 	rc = hdlc_open(dev);
1543 	if (rc)
1544 		return rc;
1545 
1546 	/* arbitrate between network and tty opens */
1547 	spin_lock_irqsave(&info->netlock, flags);
1548 	if (info->port.count != 0 || info->netcount != 0) {
1549 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1550 		spin_unlock_irqrestore(&info->netlock, flags);
1551 		return -EBUSY;
1552 	}
1553 	info->netcount=1;
1554 	spin_unlock_irqrestore(&info->netlock, flags);
1555 
1556 	/* claim resources and init adapter */
1557 	if ((rc = startup(info)) != 0) {
1558 		spin_lock_irqsave(&info->netlock, flags);
1559 		info->netcount=0;
1560 		spin_unlock_irqrestore(&info->netlock, flags);
1561 		return rc;
1562 	}
1563 
1564 	/* assert RTS and DTR, apply hardware settings */
1565 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1566 	program_hw(info);
1567 
1568 	/* enable network layer transmit */
1569 	dev->trans_start = jiffies;
1570 	netif_start_queue(dev);
1571 
1572 	/* inform generic HDLC layer of current DCD status */
1573 	spin_lock_irqsave(&info->lock, flags);
1574 	get_signals(info);
1575 	spin_unlock_irqrestore(&info->lock, flags);
1576 	if (info->signals & SerialSignal_DCD)
1577 		netif_carrier_on(dev);
1578 	else
1579 		netif_carrier_off(dev);
1580 	return 0;
1581 }
1582 
1583 /**
1584  * called by network layer when interface is disabled
1585  * shutdown hardware and release resources
1586  *
1587  * dev  pointer to network device structure
1588  *
1589  * returns 0 if success, otherwise error code
1590  */
1591 static int hdlcdev_close(struct net_device *dev)
1592 {
1593 	struct slgt_info *info = dev_to_port(dev);
1594 	unsigned long flags;
1595 
1596 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1597 
1598 	netif_stop_queue(dev);
1599 
1600 	/* shutdown adapter and release resources */
1601 	shutdown(info);
1602 
1603 	hdlc_close(dev);
1604 
1605 	spin_lock_irqsave(&info->netlock, flags);
1606 	info->netcount=0;
1607 	spin_unlock_irqrestore(&info->netlock, flags);
1608 
1609 	module_put(THIS_MODULE);
1610 	return 0;
1611 }
1612 
1613 /**
1614  * called by network layer to process IOCTL call to network device
1615  *
1616  * dev  pointer to network device structure
1617  * ifr  pointer to network interface request structure
1618  * cmd  IOCTL command code
1619  *
1620  * returns 0 if success, otherwise error code
1621  */
1622 static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1623 {
1624 	const size_t size = sizeof(sync_serial_settings);
1625 	sync_serial_settings new_line;
1626 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1627 	struct slgt_info *info = dev_to_port(dev);
1628 	unsigned int flags;
1629 
1630 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1631 
1632 	/* return error if TTY interface open */
1633 	if (info->port.count)
1634 		return -EBUSY;
1635 
1636 	if (cmd != SIOCWANDEV)
1637 		return hdlc_ioctl(dev, ifr, cmd);
1638 
1639 	memset(&new_line, 0, sizeof(new_line));
1640 
1641 	switch(ifr->ifr_settings.type) {
1642 	case IF_GET_IFACE: /* return current sync_serial_settings */
1643 
1644 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
1645 		if (ifr->ifr_settings.size < size) {
1646 			ifr->ifr_settings.size = size; /* data size wanted */
1647 			return -ENOBUFS;
1648 		}
1649 
1650 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1651 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1652 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1653 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1654 
1655 		switch (flags){
1656 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1657 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1658 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1659 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1660 		default: new_line.clock_type = CLOCK_DEFAULT;
1661 		}
1662 
1663 		new_line.clock_rate = info->params.clock_speed;
1664 		new_line.loopback   = info->params.loopback ? 1:0;
1665 
1666 		if (copy_to_user(line, &new_line, size))
1667 			return -EFAULT;
1668 		return 0;
1669 
1670 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1671 
1672 		if(!capable(CAP_NET_ADMIN))
1673 			return -EPERM;
1674 		if (copy_from_user(&new_line, line, size))
1675 			return -EFAULT;
1676 
1677 		switch (new_line.clock_type)
1678 		{
1679 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1680 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1681 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1682 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1683 		case CLOCK_DEFAULT:  flags = info->params.flags &
1684 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1685 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1686 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1687 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1688 		default: return -EINVAL;
1689 		}
1690 
1691 		if (new_line.loopback != 0 && new_line.loopback != 1)
1692 			return -EINVAL;
1693 
1694 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1695 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1696 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1697 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1698 		info->params.flags |= flags;
1699 
1700 		info->params.loopback = new_line.loopback;
1701 
1702 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1703 			info->params.clock_speed = new_line.clock_rate;
1704 		else
1705 			info->params.clock_speed = 0;
1706 
1707 		/* if network interface up, reprogram hardware */
1708 		if (info->netcount)
1709 			program_hw(info);
1710 		return 0;
1711 
1712 	default:
1713 		return hdlc_ioctl(dev, ifr, cmd);
1714 	}
1715 }
1716 
1717 /**
1718  * called by network layer when transmit timeout is detected
1719  *
1720  * dev  pointer to network device structure
1721  */
1722 static void hdlcdev_tx_timeout(struct net_device *dev)
1723 {
1724 	struct slgt_info *info = dev_to_port(dev);
1725 	unsigned long flags;
1726 
1727 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1728 
1729 	dev->stats.tx_errors++;
1730 	dev->stats.tx_aborted_errors++;
1731 
1732 	spin_lock_irqsave(&info->lock,flags);
1733 	tx_stop(info);
1734 	spin_unlock_irqrestore(&info->lock,flags);
1735 
1736 	netif_wake_queue(dev);
1737 }
1738 
1739 /**
1740  * called by device driver when transmit completes
1741  * reenable network layer transmit if stopped
1742  *
1743  * info  pointer to device instance information
1744  */
1745 static void hdlcdev_tx_done(struct slgt_info *info)
1746 {
1747 	if (netif_queue_stopped(info->netdev))
1748 		netif_wake_queue(info->netdev);
1749 }
1750 
1751 /**
1752  * called by device driver when frame received
1753  * pass frame to network layer
1754  *
1755  * info  pointer to device instance information
1756  * buf   pointer to buffer contianing frame data
1757  * size  count of data bytes in buf
1758  */
1759 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1760 {
1761 	struct sk_buff *skb = dev_alloc_skb(size);
1762 	struct net_device *dev = info->netdev;
1763 
1764 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1765 
1766 	if (skb == NULL) {
1767 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1768 		dev->stats.rx_dropped++;
1769 		return;
1770 	}
1771 
1772 	memcpy(skb_put(skb, size), buf, size);
1773 
1774 	skb->protocol = hdlc_type_trans(skb, dev);
1775 
1776 	dev->stats.rx_packets++;
1777 	dev->stats.rx_bytes += size;
1778 
1779 	netif_rx(skb);
1780 }
1781 
1782 static const struct net_device_ops hdlcdev_ops = {
1783 	.ndo_open       = hdlcdev_open,
1784 	.ndo_stop       = hdlcdev_close,
1785 	.ndo_change_mtu = hdlc_change_mtu,
1786 	.ndo_start_xmit = hdlc_start_xmit,
1787 	.ndo_do_ioctl   = hdlcdev_ioctl,
1788 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1789 };
1790 
1791 /**
1792  * called by device driver when adding device instance
1793  * do generic HDLC initialization
1794  *
1795  * info  pointer to device instance information
1796  *
1797  * returns 0 if success, otherwise error code
1798  */
1799 static int hdlcdev_init(struct slgt_info *info)
1800 {
1801 	int rc;
1802 	struct net_device *dev;
1803 	hdlc_device *hdlc;
1804 
1805 	/* allocate and initialize network and HDLC layer objects */
1806 
1807 	dev = alloc_hdlcdev(info);
1808 	if (!dev) {
1809 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1810 		return -ENOMEM;
1811 	}
1812 
1813 	/* for network layer reporting purposes only */
1814 	dev->mem_start = info->phys_reg_addr;
1815 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1816 	dev->irq       = info->irq_level;
1817 
1818 	/* network layer callbacks and settings */
1819 	dev->netdev_ops	    = &hdlcdev_ops;
1820 	dev->watchdog_timeo = 10 * HZ;
1821 	dev->tx_queue_len   = 50;
1822 
1823 	/* generic HDLC layer callbacks and settings */
1824 	hdlc         = dev_to_hdlc(dev);
1825 	hdlc->attach = hdlcdev_attach;
1826 	hdlc->xmit   = hdlcdev_xmit;
1827 
1828 	/* register objects with HDLC layer */
1829 	rc = register_hdlc_device(dev);
1830 	if (rc) {
1831 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1832 		free_netdev(dev);
1833 		return rc;
1834 	}
1835 
1836 	info->netdev = dev;
1837 	return 0;
1838 }
1839 
1840 /**
1841  * called by device driver when removing device instance
1842  * do generic HDLC cleanup
1843  *
1844  * info  pointer to device instance information
1845  */
1846 static void hdlcdev_exit(struct slgt_info *info)
1847 {
1848 	unregister_hdlc_device(info->netdev);
1849 	free_netdev(info->netdev);
1850 	info->netdev = NULL;
1851 }
1852 
1853 #endif /* ifdef CONFIG_HDLC */
1854 
1855 /*
1856  * get async data from rx DMA buffers
1857  */
1858 static void rx_async(struct slgt_info *info)
1859 {
1860  	struct mgsl_icount *icount = &info->icount;
1861 	unsigned int start, end;
1862 	unsigned char *p;
1863 	unsigned char status;
1864 	struct slgt_desc *bufs = info->rbufs;
1865 	int i, count;
1866 	int chars = 0;
1867 	int stat;
1868 	unsigned char ch;
1869 
1870 	start = end = info->rbuf_current;
1871 
1872 	while(desc_complete(bufs[end])) {
1873 		count = desc_count(bufs[end]) - info->rbuf_index;
1874 		p     = bufs[end].buf + info->rbuf_index;
1875 
1876 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1877 		DBGDATA(info, p, count, "rx");
1878 
1879 		for(i=0 ; i < count; i+=2, p+=2) {
1880 			ch = *p;
1881 			icount->rx++;
1882 
1883 			stat = 0;
1884 
1885 			status = *(p + 1) & (BIT1 + BIT0);
1886 			if (status) {
1887 				if (status & BIT1)
1888 					icount->parity++;
1889 				else if (status & BIT0)
1890 					icount->frame++;
1891 				/* discard char if tty control flags say so */
1892 				if (status & info->ignore_status_mask)
1893 					continue;
1894 				if (status & BIT1)
1895 					stat = TTY_PARITY;
1896 				else if (status & BIT0)
1897 					stat = TTY_FRAME;
1898 			}
1899 			tty_insert_flip_char(&info->port, ch, stat);
1900 			chars++;
1901 		}
1902 
1903 		if (i < count) {
1904 			/* receive buffer not completed */
1905 			info->rbuf_index += i;
1906 			mod_timer(&info->rx_timer, jiffies + 1);
1907 			break;
1908 		}
1909 
1910 		info->rbuf_index = 0;
1911 		free_rbufs(info, end, end);
1912 
1913 		if (++end == info->rbuf_count)
1914 			end = 0;
1915 
1916 		/* if entire list searched then no frame available */
1917 		if (end == start)
1918 			break;
1919 	}
1920 
1921 	if (chars)
1922 		tty_flip_buffer_push(&info->port);
1923 }
1924 
1925 /*
1926  * return next bottom half action to perform
1927  */
1928 static int bh_action(struct slgt_info *info)
1929 {
1930 	unsigned long flags;
1931 	int rc;
1932 
1933 	spin_lock_irqsave(&info->lock,flags);
1934 
1935 	if (info->pending_bh & BH_RECEIVE) {
1936 		info->pending_bh &= ~BH_RECEIVE;
1937 		rc = BH_RECEIVE;
1938 	} else if (info->pending_bh & BH_TRANSMIT) {
1939 		info->pending_bh &= ~BH_TRANSMIT;
1940 		rc = BH_TRANSMIT;
1941 	} else if (info->pending_bh & BH_STATUS) {
1942 		info->pending_bh &= ~BH_STATUS;
1943 		rc = BH_STATUS;
1944 	} else {
1945 		/* Mark BH routine as complete */
1946 		info->bh_running = false;
1947 		info->bh_requested = false;
1948 		rc = 0;
1949 	}
1950 
1951 	spin_unlock_irqrestore(&info->lock,flags);
1952 
1953 	return rc;
1954 }
1955 
1956 /*
1957  * perform bottom half processing
1958  */
1959 static void bh_handler(struct work_struct *work)
1960 {
1961 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1962 	int action;
1963 
1964 	info->bh_running = true;
1965 
1966 	while((action = bh_action(info))) {
1967 		switch (action) {
1968 		case BH_RECEIVE:
1969 			DBGBH(("%s bh receive\n", info->device_name));
1970 			switch(info->params.mode) {
1971 			case MGSL_MODE_ASYNC:
1972 				rx_async(info);
1973 				break;
1974 			case MGSL_MODE_HDLC:
1975 				while(rx_get_frame(info));
1976 				break;
1977 			case MGSL_MODE_RAW:
1978 			case MGSL_MODE_MONOSYNC:
1979 			case MGSL_MODE_BISYNC:
1980 			case MGSL_MODE_XSYNC:
1981 				while(rx_get_buf(info));
1982 				break;
1983 			}
1984 			/* restart receiver if rx DMA buffers exhausted */
1985 			if (info->rx_restart)
1986 				rx_start(info);
1987 			break;
1988 		case BH_TRANSMIT:
1989 			bh_transmit(info);
1990 			break;
1991 		case BH_STATUS:
1992 			DBGBH(("%s bh status\n", info->device_name));
1993 			info->ri_chkcount = 0;
1994 			info->dsr_chkcount = 0;
1995 			info->dcd_chkcount = 0;
1996 			info->cts_chkcount = 0;
1997 			break;
1998 		default:
1999 			DBGBH(("%s unknown action\n", info->device_name));
2000 			break;
2001 		}
2002 	}
2003 	DBGBH(("%s bh_handler exit\n", info->device_name));
2004 }
2005 
2006 static void bh_transmit(struct slgt_info *info)
2007 {
2008 	struct tty_struct *tty = info->port.tty;
2009 
2010 	DBGBH(("%s bh_transmit\n", info->device_name));
2011 	if (tty)
2012 		tty_wakeup(tty);
2013 }
2014 
2015 static void dsr_change(struct slgt_info *info, unsigned short status)
2016 {
2017 	if (status & BIT3) {
2018 		info->signals |= SerialSignal_DSR;
2019 		info->input_signal_events.dsr_up++;
2020 	} else {
2021 		info->signals &= ~SerialSignal_DSR;
2022 		info->input_signal_events.dsr_down++;
2023 	}
2024 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
2025 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2026 		slgt_irq_off(info, IRQ_DSR);
2027 		return;
2028 	}
2029 	info->icount.dsr++;
2030 	wake_up_interruptible(&info->status_event_wait_q);
2031 	wake_up_interruptible(&info->event_wait_q);
2032 	info->pending_bh |= BH_STATUS;
2033 }
2034 
2035 static void cts_change(struct slgt_info *info, unsigned short status)
2036 {
2037 	if (status & BIT2) {
2038 		info->signals |= SerialSignal_CTS;
2039 		info->input_signal_events.cts_up++;
2040 	} else {
2041 		info->signals &= ~SerialSignal_CTS;
2042 		info->input_signal_events.cts_down++;
2043 	}
2044 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
2045 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2046 		slgt_irq_off(info, IRQ_CTS);
2047 		return;
2048 	}
2049 	info->icount.cts++;
2050 	wake_up_interruptible(&info->status_event_wait_q);
2051 	wake_up_interruptible(&info->event_wait_q);
2052 	info->pending_bh |= BH_STATUS;
2053 
2054 	if (tty_port_cts_enabled(&info->port)) {
2055 		if (info->port.tty) {
2056 			if (info->port.tty->hw_stopped) {
2057 				if (info->signals & SerialSignal_CTS) {
2058 		 			info->port.tty->hw_stopped = 0;
2059 					info->pending_bh |= BH_TRANSMIT;
2060 					return;
2061 				}
2062 			} else {
2063 				if (!(info->signals & SerialSignal_CTS))
2064 		 			info->port.tty->hw_stopped = 1;
2065 			}
2066 		}
2067 	}
2068 }
2069 
2070 static void dcd_change(struct slgt_info *info, unsigned short status)
2071 {
2072 	if (status & BIT1) {
2073 		info->signals |= SerialSignal_DCD;
2074 		info->input_signal_events.dcd_up++;
2075 	} else {
2076 		info->signals &= ~SerialSignal_DCD;
2077 		info->input_signal_events.dcd_down++;
2078 	}
2079 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
2080 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2081 		slgt_irq_off(info, IRQ_DCD);
2082 		return;
2083 	}
2084 	info->icount.dcd++;
2085 #if SYNCLINK_GENERIC_HDLC
2086 	if (info->netcount) {
2087 		if (info->signals & SerialSignal_DCD)
2088 			netif_carrier_on(info->netdev);
2089 		else
2090 			netif_carrier_off(info->netdev);
2091 	}
2092 #endif
2093 	wake_up_interruptible(&info->status_event_wait_q);
2094 	wake_up_interruptible(&info->event_wait_q);
2095 	info->pending_bh |= BH_STATUS;
2096 
2097 	if (info->port.flags & ASYNC_CHECK_CD) {
2098 		if (info->signals & SerialSignal_DCD)
2099 			wake_up_interruptible(&info->port.open_wait);
2100 		else {
2101 			if (info->port.tty)
2102 				tty_hangup(info->port.tty);
2103 		}
2104 	}
2105 }
2106 
2107 static void ri_change(struct slgt_info *info, unsigned short status)
2108 {
2109 	if (status & BIT0) {
2110 		info->signals |= SerialSignal_RI;
2111 		info->input_signal_events.ri_up++;
2112 	} else {
2113 		info->signals &= ~SerialSignal_RI;
2114 		info->input_signal_events.ri_down++;
2115 	}
2116 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2117 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2118 		slgt_irq_off(info, IRQ_RI);
2119 		return;
2120 	}
2121 	info->icount.rng++;
2122 	wake_up_interruptible(&info->status_event_wait_q);
2123 	wake_up_interruptible(&info->event_wait_q);
2124 	info->pending_bh |= BH_STATUS;
2125 }
2126 
2127 static void isr_rxdata(struct slgt_info *info)
2128 {
2129 	unsigned int count = info->rbuf_fill_count;
2130 	unsigned int i = info->rbuf_fill_index;
2131 	unsigned short reg;
2132 
2133 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2134 		reg = rd_reg16(info, RDR);
2135 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2136 		if (desc_complete(info->rbufs[i])) {
2137 			/* all buffers full */
2138 			rx_stop(info);
2139 			info->rx_restart = 1;
2140 			continue;
2141 		}
2142 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2143 		/* async mode saves status byte to buffer for each data byte */
2144 		if (info->params.mode == MGSL_MODE_ASYNC)
2145 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2146 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2147 			/* buffer full or end of frame */
2148 			set_desc_count(info->rbufs[i], count);
2149 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2150 			info->rbuf_fill_count = count = 0;
2151 			if (++i == info->rbuf_count)
2152 				i = 0;
2153 			info->pending_bh |= BH_RECEIVE;
2154 		}
2155 	}
2156 
2157 	info->rbuf_fill_index = i;
2158 	info->rbuf_fill_count = count;
2159 }
2160 
2161 static void isr_serial(struct slgt_info *info)
2162 {
2163 	unsigned short status = rd_reg16(info, SSR);
2164 
2165 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2166 
2167 	wr_reg16(info, SSR, status); /* clear pending */
2168 
2169 	info->irq_occurred = true;
2170 
2171 	if (info->params.mode == MGSL_MODE_ASYNC) {
2172 		if (status & IRQ_TXIDLE) {
2173 			if (info->tx_active)
2174 				isr_txeom(info, status);
2175 		}
2176 		if (info->rx_pio && (status & IRQ_RXDATA))
2177 			isr_rxdata(info);
2178 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2179 			info->icount.brk++;
2180 			/* process break detection if tty control allows */
2181 			if (info->port.tty) {
2182 				if (!(status & info->ignore_status_mask)) {
2183 					if (info->read_status_mask & MASK_BREAK) {
2184 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2185 						if (info->port.flags & ASYNC_SAK)
2186 							do_SAK(info->port.tty);
2187 					}
2188 				}
2189 			}
2190 		}
2191 	} else {
2192 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2193 			isr_txeom(info, status);
2194 		if (info->rx_pio && (status & IRQ_RXDATA))
2195 			isr_rxdata(info);
2196 		if (status & IRQ_RXIDLE) {
2197 			if (status & RXIDLE)
2198 				info->icount.rxidle++;
2199 			else
2200 				info->icount.exithunt++;
2201 			wake_up_interruptible(&info->event_wait_q);
2202 		}
2203 
2204 		if (status & IRQ_RXOVER)
2205 			rx_start(info);
2206 	}
2207 
2208 	if (status & IRQ_DSR)
2209 		dsr_change(info, status);
2210 	if (status & IRQ_CTS)
2211 		cts_change(info, status);
2212 	if (status & IRQ_DCD)
2213 		dcd_change(info, status);
2214 	if (status & IRQ_RI)
2215 		ri_change(info, status);
2216 }
2217 
2218 static void isr_rdma(struct slgt_info *info)
2219 {
2220 	unsigned int status = rd_reg32(info, RDCSR);
2221 
2222 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2223 
2224 	/* RDCSR (rx DMA control/status)
2225 	 *
2226 	 * 31..07  reserved
2227 	 * 06      save status byte to DMA buffer
2228 	 * 05      error
2229 	 * 04      eol (end of list)
2230 	 * 03      eob (end of buffer)
2231 	 * 02      IRQ enable
2232 	 * 01      reset
2233 	 * 00      enable
2234 	 */
2235 	wr_reg32(info, RDCSR, status);	/* clear pending */
2236 
2237 	if (status & (BIT5 + BIT4)) {
2238 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2239 		info->rx_restart = true;
2240 	}
2241 	info->pending_bh |= BH_RECEIVE;
2242 }
2243 
2244 static void isr_tdma(struct slgt_info *info)
2245 {
2246 	unsigned int status = rd_reg32(info, TDCSR);
2247 
2248 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2249 
2250 	/* TDCSR (tx DMA control/status)
2251 	 *
2252 	 * 31..06  reserved
2253 	 * 05      error
2254 	 * 04      eol (end of list)
2255 	 * 03      eob (end of buffer)
2256 	 * 02      IRQ enable
2257 	 * 01      reset
2258 	 * 00      enable
2259 	 */
2260 	wr_reg32(info, TDCSR, status);	/* clear pending */
2261 
2262 	if (status & (BIT5 + BIT4 + BIT3)) {
2263 		// another transmit buffer has completed
2264 		// run bottom half to get more send data from user
2265 		info->pending_bh |= BH_TRANSMIT;
2266 	}
2267 }
2268 
2269 /*
2270  * return true if there are unsent tx DMA buffers, otherwise false
2271  *
2272  * if there are unsent buffers then info->tbuf_start
2273  * is set to index of first unsent buffer
2274  */
2275 static bool unsent_tbufs(struct slgt_info *info)
2276 {
2277 	unsigned int i = info->tbuf_current;
2278 	bool rc = false;
2279 
2280 	/*
2281 	 * search backwards from last loaded buffer (precedes tbuf_current)
2282 	 * for first unsent buffer (desc_count > 0)
2283 	 */
2284 
2285 	do {
2286 		if (i)
2287 			i--;
2288 		else
2289 			i = info->tbuf_count - 1;
2290 		if (!desc_count(info->tbufs[i]))
2291 			break;
2292 		info->tbuf_start = i;
2293 		rc = true;
2294 	} while (i != info->tbuf_current);
2295 
2296 	return rc;
2297 }
2298 
2299 static void isr_txeom(struct slgt_info *info, unsigned short status)
2300 {
2301 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2302 
2303 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2304 	tdma_reset(info);
2305 	if (status & IRQ_TXUNDER) {
2306 		unsigned short val = rd_reg16(info, TCR);
2307 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2308 		wr_reg16(info, TCR, val); /* clear reset bit */
2309 	}
2310 
2311 	if (info->tx_active) {
2312 		if (info->params.mode != MGSL_MODE_ASYNC) {
2313 			if (status & IRQ_TXUNDER)
2314 				info->icount.txunder++;
2315 			else if (status & IRQ_TXIDLE)
2316 				info->icount.txok++;
2317 		}
2318 
2319 		if (unsent_tbufs(info)) {
2320 			tx_start(info);
2321 			update_tx_timer(info);
2322 			return;
2323 		}
2324 		info->tx_active = false;
2325 
2326 		del_timer(&info->tx_timer);
2327 
2328 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2329 			info->signals &= ~SerialSignal_RTS;
2330 			info->drop_rts_on_tx_done = false;
2331 			set_signals(info);
2332 		}
2333 
2334 #if SYNCLINK_GENERIC_HDLC
2335 		if (info->netcount)
2336 			hdlcdev_tx_done(info);
2337 		else
2338 #endif
2339 		{
2340 			if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
2341 				tx_stop(info);
2342 				return;
2343 			}
2344 			info->pending_bh |= BH_TRANSMIT;
2345 		}
2346 	}
2347 }
2348 
2349 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2350 {
2351 	struct cond_wait *w, *prev;
2352 
2353 	/* wake processes waiting for specific transitions */
2354 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2355 		if (w->data & changed) {
2356 			w->data = state;
2357 			wake_up_interruptible(&w->q);
2358 			if (prev != NULL)
2359 				prev->next = w->next;
2360 			else
2361 				info->gpio_wait_q = w->next;
2362 		} else
2363 			prev = w;
2364 	}
2365 }
2366 
2367 /* interrupt service routine
2368  *
2369  * 	irq	interrupt number
2370  * 	dev_id	device ID supplied during interrupt registration
2371  */
2372 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2373 {
2374 	struct slgt_info *info = dev_id;
2375 	unsigned int gsr;
2376 	unsigned int i;
2377 
2378 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2379 
2380 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2381 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2382 		info->irq_occurred = true;
2383 		for(i=0; i < info->port_count ; i++) {
2384 			if (info->port_array[i] == NULL)
2385 				continue;
2386 			spin_lock(&info->port_array[i]->lock);
2387 			if (gsr & (BIT8 << i))
2388 				isr_serial(info->port_array[i]);
2389 			if (gsr & (BIT16 << (i*2)))
2390 				isr_rdma(info->port_array[i]);
2391 			if (gsr & (BIT17 << (i*2)))
2392 				isr_tdma(info->port_array[i]);
2393 			spin_unlock(&info->port_array[i]->lock);
2394 		}
2395 	}
2396 
2397 	if (info->gpio_present) {
2398 		unsigned int state;
2399 		unsigned int changed;
2400 		spin_lock(&info->lock);
2401 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2402 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2403 			/* read latched state of GPIO signals */
2404 			state = rd_reg32(info, IOVR);
2405 			/* clear pending GPIO interrupt bits */
2406 			wr_reg32(info, IOSR, changed);
2407 			for (i=0 ; i < info->port_count ; i++) {
2408 				if (info->port_array[i] != NULL)
2409 					isr_gpio(info->port_array[i], changed, state);
2410 			}
2411 		}
2412 		spin_unlock(&info->lock);
2413 	}
2414 
2415 	for(i=0; i < info->port_count ; i++) {
2416 		struct slgt_info *port = info->port_array[i];
2417 		if (port == NULL)
2418 			continue;
2419 		spin_lock(&port->lock);
2420 		if ((port->port.count || port->netcount) &&
2421 		    port->pending_bh && !port->bh_running &&
2422 		    !port->bh_requested) {
2423 			DBGISR(("%s bh queued\n", port->device_name));
2424 			schedule_work(&port->task);
2425 			port->bh_requested = true;
2426 		}
2427 		spin_unlock(&port->lock);
2428 	}
2429 
2430 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2431 	return IRQ_HANDLED;
2432 }
2433 
2434 static int startup(struct slgt_info *info)
2435 {
2436 	DBGINFO(("%s startup\n", info->device_name));
2437 
2438 	if (info->port.flags & ASYNC_INITIALIZED)
2439 		return 0;
2440 
2441 	if (!info->tx_buf) {
2442 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2443 		if (!info->tx_buf) {
2444 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2445 			return -ENOMEM;
2446 		}
2447 	}
2448 
2449 	info->pending_bh = 0;
2450 
2451 	memset(&info->icount, 0, sizeof(info->icount));
2452 
2453 	/* program hardware for current parameters */
2454 	change_params(info);
2455 
2456 	if (info->port.tty)
2457 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2458 
2459 	info->port.flags |= ASYNC_INITIALIZED;
2460 
2461 	return 0;
2462 }
2463 
2464 /*
2465  *  called by close() and hangup() to shutdown hardware
2466  */
2467 static void shutdown(struct slgt_info *info)
2468 {
2469 	unsigned long flags;
2470 
2471 	if (!(info->port.flags & ASYNC_INITIALIZED))
2472 		return;
2473 
2474 	DBGINFO(("%s shutdown\n", info->device_name));
2475 
2476 	/* clear status wait queue because status changes */
2477 	/* can't happen after shutting down the hardware */
2478 	wake_up_interruptible(&info->status_event_wait_q);
2479 	wake_up_interruptible(&info->event_wait_q);
2480 
2481 	del_timer_sync(&info->tx_timer);
2482 	del_timer_sync(&info->rx_timer);
2483 
2484 	kfree(info->tx_buf);
2485 	info->tx_buf = NULL;
2486 
2487 	spin_lock_irqsave(&info->lock,flags);
2488 
2489 	tx_stop(info);
2490 	rx_stop(info);
2491 
2492 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2493 
2494  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2495 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2496 		set_signals(info);
2497 	}
2498 
2499 	flush_cond_wait(&info->gpio_wait_q);
2500 
2501 	spin_unlock_irqrestore(&info->lock,flags);
2502 
2503 	if (info->port.tty)
2504 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2505 
2506 	info->port.flags &= ~ASYNC_INITIALIZED;
2507 }
2508 
2509 static void program_hw(struct slgt_info *info)
2510 {
2511 	unsigned long flags;
2512 
2513 	spin_lock_irqsave(&info->lock,flags);
2514 
2515 	rx_stop(info);
2516 	tx_stop(info);
2517 
2518 	if (info->params.mode != MGSL_MODE_ASYNC ||
2519 	    info->netcount)
2520 		sync_mode(info);
2521 	else
2522 		async_mode(info);
2523 
2524 	set_signals(info);
2525 
2526 	info->dcd_chkcount = 0;
2527 	info->cts_chkcount = 0;
2528 	info->ri_chkcount = 0;
2529 	info->dsr_chkcount = 0;
2530 
2531 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2532 	get_signals(info);
2533 
2534 	if (info->netcount ||
2535 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2536 		rx_start(info);
2537 
2538 	spin_unlock_irqrestore(&info->lock,flags);
2539 }
2540 
2541 /*
2542  * reconfigure adapter based on new parameters
2543  */
2544 static void change_params(struct slgt_info *info)
2545 {
2546 	unsigned cflag;
2547 	int bits_per_char;
2548 
2549 	if (!info->port.tty)
2550 		return;
2551 	DBGINFO(("%s change_params\n", info->device_name));
2552 
2553 	cflag = info->port.tty->termios.c_cflag;
2554 
2555 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2556 	/* otherwise assert RTS and DTR */
2557  	if (cflag & CBAUD)
2558 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2559 	else
2560 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2561 
2562 	/* byte size and parity */
2563 
2564 	switch (cflag & CSIZE) {
2565 	case CS5: info->params.data_bits = 5; break;
2566 	case CS6: info->params.data_bits = 6; break;
2567 	case CS7: info->params.data_bits = 7; break;
2568 	case CS8: info->params.data_bits = 8; break;
2569 	default:  info->params.data_bits = 7; break;
2570 	}
2571 
2572 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2573 
2574 	if (cflag & PARENB)
2575 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2576 	else
2577 		info->params.parity = ASYNC_PARITY_NONE;
2578 
2579 	/* calculate number of jiffies to transmit a full
2580 	 * FIFO (32 bytes) at specified data rate
2581 	 */
2582 	bits_per_char = info->params.data_bits +
2583 			info->params.stop_bits + 1;
2584 
2585 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2586 
2587 	if (info->params.data_rate) {
2588 		info->timeout = (32*HZ*bits_per_char) /
2589 				info->params.data_rate;
2590 	}
2591 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2592 
2593 	if (cflag & CRTSCTS)
2594 		info->port.flags |= ASYNC_CTS_FLOW;
2595 	else
2596 		info->port.flags &= ~ASYNC_CTS_FLOW;
2597 
2598 	if (cflag & CLOCAL)
2599 		info->port.flags &= ~ASYNC_CHECK_CD;
2600 	else
2601 		info->port.flags |= ASYNC_CHECK_CD;
2602 
2603 	/* process tty input control flags */
2604 
2605 	info->read_status_mask = IRQ_RXOVER;
2606 	if (I_INPCK(info->port.tty))
2607 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2608  	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2609  		info->read_status_mask |= MASK_BREAK;
2610 	if (I_IGNPAR(info->port.tty))
2611 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2612 	if (I_IGNBRK(info->port.tty)) {
2613 		info->ignore_status_mask |= MASK_BREAK;
2614 		/* If ignoring parity and break indicators, ignore
2615 		 * overruns too.  (For real raw support).
2616 		 */
2617 		if (I_IGNPAR(info->port.tty))
2618 			info->ignore_status_mask |= MASK_OVERRUN;
2619 	}
2620 
2621 	program_hw(info);
2622 }
2623 
2624 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2625 {
2626 	DBGINFO(("%s get_stats\n",  info->device_name));
2627 	if (!user_icount) {
2628 		memset(&info->icount, 0, sizeof(info->icount));
2629 	} else {
2630 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2631 			return -EFAULT;
2632 	}
2633 	return 0;
2634 }
2635 
2636 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2637 {
2638 	DBGINFO(("%s get_params\n", info->device_name));
2639 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2640 		return -EFAULT;
2641 	return 0;
2642 }
2643 
2644 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2645 {
2646  	unsigned long flags;
2647 	MGSL_PARAMS tmp_params;
2648 
2649 	DBGINFO(("%s set_params\n", info->device_name));
2650 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2651 		return -EFAULT;
2652 
2653 	spin_lock_irqsave(&info->lock, flags);
2654 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2655 		info->base_clock = tmp_params.clock_speed;
2656 	else
2657 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2658 	spin_unlock_irqrestore(&info->lock, flags);
2659 
2660 	program_hw(info);
2661 
2662 	return 0;
2663 }
2664 
2665 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2666 {
2667 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2668 	if (put_user(info->idle_mode, idle_mode))
2669 		return -EFAULT;
2670 	return 0;
2671 }
2672 
2673 static int set_txidle(struct slgt_info *info, int idle_mode)
2674 {
2675  	unsigned long flags;
2676 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2677 	spin_lock_irqsave(&info->lock,flags);
2678 	info->idle_mode = idle_mode;
2679 	if (info->params.mode != MGSL_MODE_ASYNC)
2680 		tx_set_idle(info);
2681 	spin_unlock_irqrestore(&info->lock,flags);
2682 	return 0;
2683 }
2684 
2685 static int tx_enable(struct slgt_info *info, int enable)
2686 {
2687  	unsigned long flags;
2688 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2689 	spin_lock_irqsave(&info->lock,flags);
2690 	if (enable) {
2691 		if (!info->tx_enabled)
2692 			tx_start(info);
2693 	} else {
2694 		if (info->tx_enabled)
2695 			tx_stop(info);
2696 	}
2697 	spin_unlock_irqrestore(&info->lock,flags);
2698 	return 0;
2699 }
2700 
2701 /*
2702  * abort transmit HDLC frame
2703  */
2704 static int tx_abort(struct slgt_info *info)
2705 {
2706  	unsigned long flags;
2707 	DBGINFO(("%s tx_abort\n", info->device_name));
2708 	spin_lock_irqsave(&info->lock,flags);
2709 	tdma_reset(info);
2710 	spin_unlock_irqrestore(&info->lock,flags);
2711 	return 0;
2712 }
2713 
2714 static int rx_enable(struct slgt_info *info, int enable)
2715 {
2716  	unsigned long flags;
2717 	unsigned int rbuf_fill_level;
2718 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2719 	spin_lock_irqsave(&info->lock,flags);
2720 	/*
2721 	 * enable[31..16] = receive DMA buffer fill level
2722 	 * 0 = noop (leave fill level unchanged)
2723 	 * fill level must be multiple of 4 and <= buffer size
2724 	 */
2725 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2726 	if (rbuf_fill_level) {
2727 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2728 			spin_unlock_irqrestore(&info->lock, flags);
2729 			return -EINVAL;
2730 		}
2731 		info->rbuf_fill_level = rbuf_fill_level;
2732 		if (rbuf_fill_level < 128)
2733 			info->rx_pio = 1; /* PIO mode */
2734 		else
2735 			info->rx_pio = 0; /* DMA mode */
2736 		rx_stop(info); /* restart receiver to use new fill level */
2737 	}
2738 
2739 	/*
2740 	 * enable[1..0] = receiver enable command
2741 	 * 0 = disable
2742 	 * 1 = enable
2743 	 * 2 = enable or force hunt mode if already enabled
2744 	 */
2745 	enable &= 3;
2746 	if (enable) {
2747 		if (!info->rx_enabled)
2748 			rx_start(info);
2749 		else if (enable == 2) {
2750 			/* force hunt mode (write 1 to RCR[3]) */
2751 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2752 		}
2753 	} else {
2754 		if (info->rx_enabled)
2755 			rx_stop(info);
2756 	}
2757 	spin_unlock_irqrestore(&info->lock,flags);
2758 	return 0;
2759 }
2760 
2761 /*
2762  *  wait for specified event to occur
2763  */
2764 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2765 {
2766  	unsigned long flags;
2767 	int s;
2768 	int rc=0;
2769 	struct mgsl_icount cprev, cnow;
2770 	int events;
2771 	int mask;
2772 	struct	_input_signal_events oldsigs, newsigs;
2773 	DECLARE_WAITQUEUE(wait, current);
2774 
2775 	if (get_user(mask, mask_ptr))
2776 		return -EFAULT;
2777 
2778 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2779 
2780 	spin_lock_irqsave(&info->lock,flags);
2781 
2782 	/* return immediately if state matches requested events */
2783 	get_signals(info);
2784 	s = info->signals;
2785 
2786 	events = mask &
2787 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2788  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2789 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2790 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2791 	if (events) {
2792 		spin_unlock_irqrestore(&info->lock,flags);
2793 		goto exit;
2794 	}
2795 
2796 	/* save current irq counts */
2797 	cprev = info->icount;
2798 	oldsigs = info->input_signal_events;
2799 
2800 	/* enable hunt and idle irqs if needed */
2801 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2802 		unsigned short val = rd_reg16(info, SCR);
2803 		if (!(val & IRQ_RXIDLE))
2804 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2805 	}
2806 
2807 	set_current_state(TASK_INTERRUPTIBLE);
2808 	add_wait_queue(&info->event_wait_q, &wait);
2809 
2810 	spin_unlock_irqrestore(&info->lock,flags);
2811 
2812 	for(;;) {
2813 		schedule();
2814 		if (signal_pending(current)) {
2815 			rc = -ERESTARTSYS;
2816 			break;
2817 		}
2818 
2819 		/* get current irq counts */
2820 		spin_lock_irqsave(&info->lock,flags);
2821 		cnow = info->icount;
2822 		newsigs = info->input_signal_events;
2823 		set_current_state(TASK_INTERRUPTIBLE);
2824 		spin_unlock_irqrestore(&info->lock,flags);
2825 
2826 		/* if no change, wait aborted for some reason */
2827 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2828 		    newsigs.dsr_down == oldsigs.dsr_down &&
2829 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2830 		    newsigs.dcd_down == oldsigs.dcd_down &&
2831 		    newsigs.cts_up   == oldsigs.cts_up   &&
2832 		    newsigs.cts_down == oldsigs.cts_down &&
2833 		    newsigs.ri_up    == oldsigs.ri_up    &&
2834 		    newsigs.ri_down  == oldsigs.ri_down  &&
2835 		    cnow.exithunt    == cprev.exithunt   &&
2836 		    cnow.rxidle      == cprev.rxidle) {
2837 			rc = -EIO;
2838 			break;
2839 		}
2840 
2841 		events = mask &
2842 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2843 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2844 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2845 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2846 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2847 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2848 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2849 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2850 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2851 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2852 		if (events)
2853 			break;
2854 
2855 		cprev = cnow;
2856 		oldsigs = newsigs;
2857 	}
2858 
2859 	remove_wait_queue(&info->event_wait_q, &wait);
2860 	set_current_state(TASK_RUNNING);
2861 
2862 
2863 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2864 		spin_lock_irqsave(&info->lock,flags);
2865 		if (!waitqueue_active(&info->event_wait_q)) {
2866 			/* disable enable exit hunt mode/idle rcvd IRQs */
2867 			wr_reg16(info, SCR,
2868 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2869 		}
2870 		spin_unlock_irqrestore(&info->lock,flags);
2871 	}
2872 exit:
2873 	if (rc == 0)
2874 		rc = put_user(events, mask_ptr);
2875 	return rc;
2876 }
2877 
2878 static int get_interface(struct slgt_info *info, int __user *if_mode)
2879 {
2880 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2881 	if (put_user(info->if_mode, if_mode))
2882 		return -EFAULT;
2883 	return 0;
2884 }
2885 
2886 static int set_interface(struct slgt_info *info, int if_mode)
2887 {
2888  	unsigned long flags;
2889 	unsigned short val;
2890 
2891 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2892 	spin_lock_irqsave(&info->lock,flags);
2893 	info->if_mode = if_mode;
2894 
2895 	msc_set_vcr(info);
2896 
2897 	/* TCR (tx control) 07  1=RTS driver control */
2898 	val = rd_reg16(info, TCR);
2899 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2900 		val |= BIT7;
2901 	else
2902 		val &= ~BIT7;
2903 	wr_reg16(info, TCR, val);
2904 
2905 	spin_unlock_irqrestore(&info->lock,flags);
2906 	return 0;
2907 }
2908 
2909 static int get_xsync(struct slgt_info *info, int __user *xsync)
2910 {
2911 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2912 	if (put_user(info->xsync, xsync))
2913 		return -EFAULT;
2914 	return 0;
2915 }
2916 
2917 /*
2918  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2919  *
2920  * sync pattern is contained in least significant bytes of value
2921  * most significant byte of sync pattern is oldest (1st sent/detected)
2922  */
2923 static int set_xsync(struct slgt_info *info, int xsync)
2924 {
2925 	unsigned long flags;
2926 
2927 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2928 	spin_lock_irqsave(&info->lock, flags);
2929 	info->xsync = xsync;
2930 	wr_reg32(info, XSR, xsync);
2931 	spin_unlock_irqrestore(&info->lock, flags);
2932 	return 0;
2933 }
2934 
2935 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2936 {
2937 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2938 	if (put_user(info->xctrl, xctrl))
2939 		return -EFAULT;
2940 	return 0;
2941 }
2942 
2943 /*
2944  * set extended control options
2945  *
2946  * xctrl[31:19] reserved, must be zero
2947  * xctrl[18:17] extended sync pattern length in bytes
2948  *              00 = 1 byte  in xsr[7:0]
2949  *              01 = 2 bytes in xsr[15:0]
2950  *              10 = 3 bytes in xsr[23:0]
2951  *              11 = 4 bytes in xsr[31:0]
2952  * xctrl[16]    1 = enable terminal count, 0=disabled
2953  * xctrl[15:0]  receive terminal count for fixed length packets
2954  *              value is count minus one (0 = 1 byte packet)
2955  *              when terminal count is reached, receiver
2956  *              automatically returns to hunt mode and receive
2957  *              FIFO contents are flushed to DMA buffers with
2958  *              end of frame (EOF) status
2959  */
2960 static int set_xctrl(struct slgt_info *info, int xctrl)
2961 {
2962 	unsigned long flags;
2963 
2964 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2965 	spin_lock_irqsave(&info->lock, flags);
2966 	info->xctrl = xctrl;
2967 	wr_reg32(info, XCR, xctrl);
2968 	spin_unlock_irqrestore(&info->lock, flags);
2969 	return 0;
2970 }
2971 
2972 /*
2973  * set general purpose IO pin state and direction
2974  *
2975  * user_gpio fields:
2976  * state   each bit indicates a pin state
2977  * smask   set bit indicates pin state to set
2978  * dir     each bit indicates a pin direction (0=input, 1=output)
2979  * dmask   set bit indicates pin direction to set
2980  */
2981 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2982 {
2983  	unsigned long flags;
2984 	struct gpio_desc gpio;
2985 	__u32 data;
2986 
2987 	if (!info->gpio_present)
2988 		return -EINVAL;
2989 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2990 		return -EFAULT;
2991 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2992 		 info->device_name, gpio.state, gpio.smask,
2993 		 gpio.dir, gpio.dmask));
2994 
2995 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2996 	if (gpio.dmask) {
2997 		data = rd_reg32(info, IODR);
2998 		data |= gpio.dmask & gpio.dir;
2999 		data &= ~(gpio.dmask & ~gpio.dir);
3000 		wr_reg32(info, IODR, data);
3001 	}
3002 	if (gpio.smask) {
3003 		data = rd_reg32(info, IOVR);
3004 		data |= gpio.smask & gpio.state;
3005 		data &= ~(gpio.smask & ~gpio.state);
3006 		wr_reg32(info, IOVR, data);
3007 	}
3008 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3009 
3010 	return 0;
3011 }
3012 
3013 /*
3014  * get general purpose IO pin state and direction
3015  */
3016 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3017 {
3018 	struct gpio_desc gpio;
3019 	if (!info->gpio_present)
3020 		return -EINVAL;
3021 	gpio.state = rd_reg32(info, IOVR);
3022 	gpio.smask = 0xffffffff;
3023 	gpio.dir   = rd_reg32(info, IODR);
3024 	gpio.dmask = 0xffffffff;
3025 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3026 		return -EFAULT;
3027 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
3028 		 info->device_name, gpio.state, gpio.dir));
3029 	return 0;
3030 }
3031 
3032 /*
3033  * conditional wait facility
3034  */
3035 static void init_cond_wait(struct cond_wait *w, unsigned int data)
3036 {
3037 	init_waitqueue_head(&w->q);
3038 	init_waitqueue_entry(&w->wait, current);
3039 	w->data = data;
3040 }
3041 
3042 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
3043 {
3044 	set_current_state(TASK_INTERRUPTIBLE);
3045 	add_wait_queue(&w->q, &w->wait);
3046 	w->next = *head;
3047 	*head = w;
3048 }
3049 
3050 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
3051 {
3052 	struct cond_wait *w, *prev;
3053 	remove_wait_queue(&cw->q, &cw->wait);
3054 	set_current_state(TASK_RUNNING);
3055 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
3056 		if (w == cw) {
3057 			if (prev != NULL)
3058 				prev->next = w->next;
3059 			else
3060 				*head = w->next;
3061 			break;
3062 		}
3063 	}
3064 }
3065 
3066 static void flush_cond_wait(struct cond_wait **head)
3067 {
3068 	while (*head != NULL) {
3069 		wake_up_interruptible(&(*head)->q);
3070 		*head = (*head)->next;
3071 	}
3072 }
3073 
3074 /*
3075  * wait for general purpose I/O pin(s) to enter specified state
3076  *
3077  * user_gpio fields:
3078  * state - bit indicates target pin state
3079  * smask - set bit indicates watched pin
3080  *
3081  * The wait ends when at least one watched pin enters the specified
3082  * state. When 0 (no error) is returned, user_gpio->state is set to the
3083  * state of all GPIO pins when the wait ends.
3084  *
3085  * Note: Each pin may be a dedicated input, dedicated output, or
3086  * configurable input/output. The number and configuration of pins
3087  * varies with the specific adapter model. Only input pins (dedicated
3088  * or configured) can be monitored with this function.
3089  */
3090 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3091 {
3092  	unsigned long flags;
3093 	int rc = 0;
3094 	struct gpio_desc gpio;
3095 	struct cond_wait wait;
3096 	u32 state;
3097 
3098 	if (!info->gpio_present)
3099 		return -EINVAL;
3100 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
3101 		return -EFAULT;
3102 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3103 		 info->device_name, gpio.state, gpio.smask));
3104 	/* ignore output pins identified by set IODR bit */
3105 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3106 		return -EINVAL;
3107 	init_cond_wait(&wait, gpio.smask);
3108 
3109 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3110 	/* enable interrupts for watched pins */
3111 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3112 	/* get current pin states */
3113 	state = rd_reg32(info, IOVR);
3114 
3115 	if (gpio.smask & ~(state ^ gpio.state)) {
3116 		/* already in target state */
3117 		gpio.state = state;
3118 	} else {
3119 		/* wait for target state */
3120 		add_cond_wait(&info->gpio_wait_q, &wait);
3121 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3122 		schedule();
3123 		if (signal_pending(current))
3124 			rc = -ERESTARTSYS;
3125 		else
3126 			gpio.state = wait.data;
3127 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3128 		remove_cond_wait(&info->gpio_wait_q, &wait);
3129 	}
3130 
3131 	/* disable all GPIO interrupts if no waiting processes */
3132 	if (info->gpio_wait_q == NULL)
3133 		wr_reg32(info, IOER, 0);
3134 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3135 
3136 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3137 		rc = -EFAULT;
3138 	return rc;
3139 }
3140 
3141 static int modem_input_wait(struct slgt_info *info,int arg)
3142 {
3143  	unsigned long flags;
3144 	int rc;
3145 	struct mgsl_icount cprev, cnow;
3146 	DECLARE_WAITQUEUE(wait, current);
3147 
3148 	/* save current irq counts */
3149 	spin_lock_irqsave(&info->lock,flags);
3150 	cprev = info->icount;
3151 	add_wait_queue(&info->status_event_wait_q, &wait);
3152 	set_current_state(TASK_INTERRUPTIBLE);
3153 	spin_unlock_irqrestore(&info->lock,flags);
3154 
3155 	for(;;) {
3156 		schedule();
3157 		if (signal_pending(current)) {
3158 			rc = -ERESTARTSYS;
3159 			break;
3160 		}
3161 
3162 		/* get new irq counts */
3163 		spin_lock_irqsave(&info->lock,flags);
3164 		cnow = info->icount;
3165 		set_current_state(TASK_INTERRUPTIBLE);
3166 		spin_unlock_irqrestore(&info->lock,flags);
3167 
3168 		/* if no change, wait aborted for some reason */
3169 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3170 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3171 			rc = -EIO;
3172 			break;
3173 		}
3174 
3175 		/* check for change in caller specified modem input */
3176 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3177 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3178 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3179 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3180 			rc = 0;
3181 			break;
3182 		}
3183 
3184 		cprev = cnow;
3185 	}
3186 	remove_wait_queue(&info->status_event_wait_q, &wait);
3187 	set_current_state(TASK_RUNNING);
3188 	return rc;
3189 }
3190 
3191 /*
3192  *  return state of serial control and status signals
3193  */
3194 static int tiocmget(struct tty_struct *tty)
3195 {
3196 	struct slgt_info *info = tty->driver_data;
3197 	unsigned int result;
3198  	unsigned long flags;
3199 
3200 	spin_lock_irqsave(&info->lock,flags);
3201  	get_signals(info);
3202 	spin_unlock_irqrestore(&info->lock,flags);
3203 
3204 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3205 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3206 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3207 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3208 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3209 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3210 
3211 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3212 	return result;
3213 }
3214 
3215 /*
3216  * set modem control signals (DTR/RTS)
3217  *
3218  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3219  *		TIOCMSET = set/clear signal values
3220  * 	value	bit mask for command
3221  */
3222 static int tiocmset(struct tty_struct *tty,
3223 		    unsigned int set, unsigned int clear)
3224 {
3225 	struct slgt_info *info = tty->driver_data;
3226  	unsigned long flags;
3227 
3228 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3229 
3230 	if (set & TIOCM_RTS)
3231 		info->signals |= SerialSignal_RTS;
3232 	if (set & TIOCM_DTR)
3233 		info->signals |= SerialSignal_DTR;
3234 	if (clear & TIOCM_RTS)
3235 		info->signals &= ~SerialSignal_RTS;
3236 	if (clear & TIOCM_DTR)
3237 		info->signals &= ~SerialSignal_DTR;
3238 
3239 	spin_lock_irqsave(&info->lock,flags);
3240  	set_signals(info);
3241 	spin_unlock_irqrestore(&info->lock,flags);
3242 	return 0;
3243 }
3244 
3245 static int carrier_raised(struct tty_port *port)
3246 {
3247 	unsigned long flags;
3248 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3249 
3250 	spin_lock_irqsave(&info->lock,flags);
3251  	get_signals(info);
3252 	spin_unlock_irqrestore(&info->lock,flags);
3253 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3254 }
3255 
3256 static void dtr_rts(struct tty_port *port, int on)
3257 {
3258 	unsigned long flags;
3259 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3260 
3261 	spin_lock_irqsave(&info->lock,flags);
3262 	if (on)
3263 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3264 	else
3265 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3266  	set_signals(info);
3267 	spin_unlock_irqrestore(&info->lock,flags);
3268 }
3269 
3270 
3271 /*
3272  *  block current process until the device is ready to open
3273  */
3274 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3275 			   struct slgt_info *info)
3276 {
3277 	DECLARE_WAITQUEUE(wait, current);
3278 	int		retval;
3279 	bool		do_clocal = false;
3280 	unsigned long	flags;
3281 	int		cd;
3282 	struct tty_port *port = &info->port;
3283 
3284 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3285 
3286 	if (filp->f_flags & O_NONBLOCK || tty->flags & (1 << TTY_IO_ERROR)){
3287 		/* nonblock mode is set or port is not enabled */
3288 		port->flags |= ASYNC_NORMAL_ACTIVE;
3289 		return 0;
3290 	}
3291 
3292 	if (tty->termios.c_cflag & CLOCAL)
3293 		do_clocal = true;
3294 
3295 	/* Wait for carrier detect and the line to become
3296 	 * free (i.e., not in use by the callout).  While we are in
3297 	 * this loop, port->count is dropped by one, so that
3298 	 * close() knows when to free things.  We restore it upon
3299 	 * exit, either normal or abnormal.
3300 	 */
3301 
3302 	retval = 0;
3303 	add_wait_queue(&port->open_wait, &wait);
3304 
3305 	spin_lock_irqsave(&info->lock, flags);
3306 	port->count--;
3307 	spin_unlock_irqrestore(&info->lock, flags);
3308 	port->blocked_open++;
3309 
3310 	while (1) {
3311 		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
3312 			tty_port_raise_dtr_rts(port);
3313 
3314 		set_current_state(TASK_INTERRUPTIBLE);
3315 
3316 		if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)){
3317 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3318 					-EAGAIN : -ERESTARTSYS;
3319 			break;
3320 		}
3321 
3322 		cd = tty_port_carrier_raised(port);
3323 
3324  		if (!(port->flags & ASYNC_CLOSING) && (do_clocal || cd ))
3325  			break;
3326 
3327 		if (signal_pending(current)) {
3328 			retval = -ERESTARTSYS;
3329 			break;
3330 		}
3331 
3332 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3333 		tty_unlock(tty);
3334 		schedule();
3335 		tty_lock(tty);
3336 	}
3337 
3338 	set_current_state(TASK_RUNNING);
3339 	remove_wait_queue(&port->open_wait, &wait);
3340 
3341 	if (!tty_hung_up_p(filp))
3342 		port->count++;
3343 	port->blocked_open--;
3344 
3345 	if (!retval)
3346 		port->flags |= ASYNC_NORMAL_ACTIVE;
3347 
3348 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3349 	return retval;
3350 }
3351 
3352 /*
3353  * allocate buffers used for calling line discipline receive_buf
3354  * directly in synchronous mode
3355  * note: add 5 bytes to max frame size to allow appending
3356  * 32-bit CRC and status byte when configured to do so
3357  */
3358 static int alloc_tmp_rbuf(struct slgt_info *info)
3359 {
3360 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3361 	if (info->tmp_rbuf == NULL)
3362 		return -ENOMEM;
3363 	/* unused flag buffer to satisfy receive_buf calling interface */
3364 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3365 	if (!info->flag_buf) {
3366 		kfree(info->tmp_rbuf);
3367 		info->tmp_rbuf = NULL;
3368 		return -ENOMEM;
3369 	}
3370 	return 0;
3371 }
3372 
3373 static void free_tmp_rbuf(struct slgt_info *info)
3374 {
3375 	kfree(info->tmp_rbuf);
3376 	info->tmp_rbuf = NULL;
3377 	kfree(info->flag_buf);
3378 	info->flag_buf = NULL;
3379 }
3380 
3381 /*
3382  * allocate DMA descriptor lists.
3383  */
3384 static int alloc_desc(struct slgt_info *info)
3385 {
3386 	unsigned int i;
3387 	unsigned int pbufs;
3388 
3389 	/* allocate memory to hold descriptor lists */
3390 	info->bufs = pci_zalloc_consistent(info->pdev, DESC_LIST_SIZE,
3391 					   &info->bufs_dma_addr);
3392 	if (info->bufs == NULL)
3393 		return -ENOMEM;
3394 
3395 	info->rbufs = (struct slgt_desc*)info->bufs;
3396 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3397 
3398 	pbufs = (unsigned int)info->bufs_dma_addr;
3399 
3400 	/*
3401 	 * Build circular lists of descriptors
3402 	 */
3403 
3404 	for (i=0; i < info->rbuf_count; i++) {
3405 		/* physical address of this descriptor */
3406 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3407 
3408 		/* physical address of next descriptor */
3409 		if (i == info->rbuf_count - 1)
3410 			info->rbufs[i].next = cpu_to_le32(pbufs);
3411 		else
3412 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3413 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3414 	}
3415 
3416 	for (i=0; i < info->tbuf_count; i++) {
3417 		/* physical address of this descriptor */
3418 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3419 
3420 		/* physical address of next descriptor */
3421 		if (i == info->tbuf_count - 1)
3422 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3423 		else
3424 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3425 	}
3426 
3427 	return 0;
3428 }
3429 
3430 static void free_desc(struct slgt_info *info)
3431 {
3432 	if (info->bufs != NULL) {
3433 		pci_free_consistent(info->pdev, DESC_LIST_SIZE, info->bufs, info->bufs_dma_addr);
3434 		info->bufs  = NULL;
3435 		info->rbufs = NULL;
3436 		info->tbufs = NULL;
3437 	}
3438 }
3439 
3440 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3441 {
3442 	int i;
3443 	for (i=0; i < count; i++) {
3444 		if ((bufs[i].buf = pci_alloc_consistent(info->pdev, DMABUFSIZE, &bufs[i].buf_dma_addr)) == NULL)
3445 			return -ENOMEM;
3446 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3447 	}
3448 	return 0;
3449 }
3450 
3451 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3452 {
3453 	int i;
3454 	for (i=0; i < count; i++) {
3455 		if (bufs[i].buf == NULL)
3456 			continue;
3457 		pci_free_consistent(info->pdev, DMABUFSIZE, bufs[i].buf, bufs[i].buf_dma_addr);
3458 		bufs[i].buf = NULL;
3459 	}
3460 }
3461 
3462 static int alloc_dma_bufs(struct slgt_info *info)
3463 {
3464 	info->rbuf_count = 32;
3465 	info->tbuf_count = 32;
3466 
3467 	if (alloc_desc(info) < 0 ||
3468 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3469 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3470 	    alloc_tmp_rbuf(info) < 0) {
3471 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3472 		return -ENOMEM;
3473 	}
3474 	reset_rbufs(info);
3475 	return 0;
3476 }
3477 
3478 static void free_dma_bufs(struct slgt_info *info)
3479 {
3480 	if (info->bufs) {
3481 		free_bufs(info, info->rbufs, info->rbuf_count);
3482 		free_bufs(info, info->tbufs, info->tbuf_count);
3483 		free_desc(info);
3484 	}
3485 	free_tmp_rbuf(info);
3486 }
3487 
3488 static int claim_resources(struct slgt_info *info)
3489 {
3490 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3491 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3492 			info->device_name, info->phys_reg_addr));
3493 		info->init_error = DiagStatus_AddressConflict;
3494 		goto errout;
3495 	}
3496 	else
3497 		info->reg_addr_requested = true;
3498 
3499 	info->reg_addr = ioremap_nocache(info->phys_reg_addr, SLGT_REG_SIZE);
3500 	if (!info->reg_addr) {
3501 		DBGERR(("%s can't map device registers, addr=%08X\n",
3502 			info->device_name, info->phys_reg_addr));
3503 		info->init_error = DiagStatus_CantAssignPciResources;
3504 		goto errout;
3505 	}
3506 	return 0;
3507 
3508 errout:
3509 	release_resources(info);
3510 	return -ENODEV;
3511 }
3512 
3513 static void release_resources(struct slgt_info *info)
3514 {
3515 	if (info->irq_requested) {
3516 		free_irq(info->irq_level, info);
3517 		info->irq_requested = false;
3518 	}
3519 
3520 	if (info->reg_addr_requested) {
3521 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3522 		info->reg_addr_requested = false;
3523 	}
3524 
3525 	if (info->reg_addr) {
3526 		iounmap(info->reg_addr);
3527 		info->reg_addr = NULL;
3528 	}
3529 }
3530 
3531 /* Add the specified device instance data structure to the
3532  * global linked list of devices and increment the device count.
3533  */
3534 static void add_device(struct slgt_info *info)
3535 {
3536 	char *devstr;
3537 
3538 	info->next_device = NULL;
3539 	info->line = slgt_device_count;
3540 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3541 
3542 	if (info->line < MAX_DEVICES) {
3543 		if (maxframe[info->line])
3544 			info->max_frame_size = maxframe[info->line];
3545 	}
3546 
3547 	slgt_device_count++;
3548 
3549 	if (!slgt_device_list)
3550 		slgt_device_list = info;
3551 	else {
3552 		struct slgt_info *current_dev = slgt_device_list;
3553 		while(current_dev->next_device)
3554 			current_dev = current_dev->next_device;
3555 		current_dev->next_device = info;
3556 	}
3557 
3558 	if (info->max_frame_size < 4096)
3559 		info->max_frame_size = 4096;
3560 	else if (info->max_frame_size > 65535)
3561 		info->max_frame_size = 65535;
3562 
3563 	switch(info->pdev->device) {
3564 	case SYNCLINK_GT_DEVICE_ID:
3565 		devstr = "GT";
3566 		break;
3567 	case SYNCLINK_GT2_DEVICE_ID:
3568 		devstr = "GT2";
3569 		break;
3570 	case SYNCLINK_GT4_DEVICE_ID:
3571 		devstr = "GT4";
3572 		break;
3573 	case SYNCLINK_AC_DEVICE_ID:
3574 		devstr = "AC";
3575 		info->params.mode = MGSL_MODE_ASYNC;
3576 		break;
3577 	default:
3578 		devstr = "(unknown model)";
3579 	}
3580 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3581 		devstr, info->device_name, info->phys_reg_addr,
3582 		info->irq_level, info->max_frame_size);
3583 
3584 #if SYNCLINK_GENERIC_HDLC
3585 	hdlcdev_init(info);
3586 #endif
3587 }
3588 
3589 static const struct tty_port_operations slgt_port_ops = {
3590 	.carrier_raised = carrier_raised,
3591 	.dtr_rts = dtr_rts,
3592 };
3593 
3594 /*
3595  *  allocate device instance structure, return NULL on failure
3596  */
3597 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3598 {
3599 	struct slgt_info *info;
3600 
3601 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3602 
3603 	if (!info) {
3604 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3605 			driver_name, adapter_num, port_num));
3606 	} else {
3607 		tty_port_init(&info->port);
3608 		info->port.ops = &slgt_port_ops;
3609 		info->magic = MGSL_MAGIC;
3610 		INIT_WORK(&info->task, bh_handler);
3611 		info->max_frame_size = 4096;
3612 		info->base_clock = 14745600;
3613 		info->rbuf_fill_level = DMABUFSIZE;
3614 		info->port.close_delay = 5*HZ/10;
3615 		info->port.closing_wait = 30*HZ;
3616 		init_waitqueue_head(&info->status_event_wait_q);
3617 		init_waitqueue_head(&info->event_wait_q);
3618 		spin_lock_init(&info->netlock);
3619 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3620 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3621 		info->adapter_num = adapter_num;
3622 		info->port_num = port_num;
3623 
3624 		setup_timer(&info->tx_timer, tx_timeout, (unsigned long)info);
3625 		setup_timer(&info->rx_timer, rx_timeout, (unsigned long)info);
3626 
3627 		/* Copy configuration info to device instance data */
3628 		info->pdev = pdev;
3629 		info->irq_level = pdev->irq;
3630 		info->phys_reg_addr = pci_resource_start(pdev,0);
3631 
3632 		info->bus_type = MGSL_BUS_TYPE_PCI;
3633 		info->irq_flags = IRQF_SHARED;
3634 
3635 		info->init_error = -1; /* assume error, set to 0 on successful init */
3636 	}
3637 
3638 	return info;
3639 }
3640 
3641 static void device_init(int adapter_num, struct pci_dev *pdev)
3642 {
3643 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3644 	int i;
3645 	int port_count = 1;
3646 
3647 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3648 		port_count = 2;
3649 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3650 		port_count = 4;
3651 
3652 	/* allocate device instances for all ports */
3653 	for (i=0; i < port_count; ++i) {
3654 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3655 		if (port_array[i] == NULL) {
3656 			for (--i; i >= 0; --i) {
3657 				tty_port_destroy(&port_array[i]->port);
3658 				kfree(port_array[i]);
3659 			}
3660 			return;
3661 		}
3662 	}
3663 
3664 	/* give copy of port_array to all ports and add to device list  */
3665 	for (i=0; i < port_count; ++i) {
3666 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3667 		add_device(port_array[i]);
3668 		port_array[i]->port_count = port_count;
3669 		spin_lock_init(&port_array[i]->lock);
3670 	}
3671 
3672 	/* Allocate and claim adapter resources */
3673 	if (!claim_resources(port_array[0])) {
3674 
3675 		alloc_dma_bufs(port_array[0]);
3676 
3677 		/* copy resource information from first port to others */
3678 		for (i = 1; i < port_count; ++i) {
3679 			port_array[i]->irq_level = port_array[0]->irq_level;
3680 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3681 			alloc_dma_bufs(port_array[i]);
3682 		}
3683 
3684 		if (request_irq(port_array[0]->irq_level,
3685 					slgt_interrupt,
3686 					port_array[0]->irq_flags,
3687 					port_array[0]->device_name,
3688 					port_array[0]) < 0) {
3689 			DBGERR(("%s request_irq failed IRQ=%d\n",
3690 				port_array[0]->device_name,
3691 				port_array[0]->irq_level));
3692 		} else {
3693 			port_array[0]->irq_requested = true;
3694 			adapter_test(port_array[0]);
3695 			for (i=1 ; i < port_count ; i++) {
3696 				port_array[i]->init_error = port_array[0]->init_error;
3697 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3698 			}
3699 		}
3700 	}
3701 
3702 	for (i = 0; i < port_count; ++i) {
3703 		struct slgt_info *info = port_array[i];
3704 		tty_port_register_device(&info->port, serial_driver, info->line,
3705 				&info->pdev->dev);
3706 	}
3707 }
3708 
3709 static int init_one(struct pci_dev *dev,
3710 			      const struct pci_device_id *ent)
3711 {
3712 	if (pci_enable_device(dev)) {
3713 		printk("error enabling pci device %p\n", dev);
3714 		return -EIO;
3715 	}
3716 	pci_set_master(dev);
3717 	device_init(slgt_device_count, dev);
3718 	return 0;
3719 }
3720 
3721 static void remove_one(struct pci_dev *dev)
3722 {
3723 }
3724 
3725 static const struct tty_operations ops = {
3726 	.open = open,
3727 	.close = close,
3728 	.write = write,
3729 	.put_char = put_char,
3730 	.flush_chars = flush_chars,
3731 	.write_room = write_room,
3732 	.chars_in_buffer = chars_in_buffer,
3733 	.flush_buffer = flush_buffer,
3734 	.ioctl = ioctl,
3735 	.compat_ioctl = slgt_compat_ioctl,
3736 	.throttle = throttle,
3737 	.unthrottle = unthrottle,
3738 	.send_xchar = send_xchar,
3739 	.break_ctl = set_break,
3740 	.wait_until_sent = wait_until_sent,
3741 	.set_termios = set_termios,
3742 	.stop = tx_hold,
3743 	.start = tx_release,
3744 	.hangup = hangup,
3745 	.tiocmget = tiocmget,
3746 	.tiocmset = tiocmset,
3747 	.get_icount = get_icount,
3748 	.proc_fops = &synclink_gt_proc_fops,
3749 };
3750 
3751 static void slgt_cleanup(void)
3752 {
3753 	int rc;
3754 	struct slgt_info *info;
3755 	struct slgt_info *tmp;
3756 
3757 	printk(KERN_INFO "unload %s\n", driver_name);
3758 
3759 	if (serial_driver) {
3760 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3761 			tty_unregister_device(serial_driver, info->line);
3762 		rc = tty_unregister_driver(serial_driver);
3763 		if (rc)
3764 			DBGERR(("tty_unregister_driver error=%d\n", rc));
3765 		put_tty_driver(serial_driver);
3766 	}
3767 
3768 	/* reset devices */
3769 	info = slgt_device_list;
3770 	while(info) {
3771 		reset_port(info);
3772 		info = info->next_device;
3773 	}
3774 
3775 	/* release devices */
3776 	info = slgt_device_list;
3777 	while(info) {
3778 #if SYNCLINK_GENERIC_HDLC
3779 		hdlcdev_exit(info);
3780 #endif
3781 		free_dma_bufs(info);
3782 		free_tmp_rbuf(info);
3783 		if (info->port_num == 0)
3784 			release_resources(info);
3785 		tmp = info;
3786 		info = info->next_device;
3787 		tty_port_destroy(&tmp->port);
3788 		kfree(tmp);
3789 	}
3790 
3791 	if (pci_registered)
3792 		pci_unregister_driver(&pci_driver);
3793 }
3794 
3795 /*
3796  *  Driver initialization entry point.
3797  */
3798 static int __init slgt_init(void)
3799 {
3800 	int rc;
3801 
3802 	printk(KERN_INFO "%s\n", driver_name);
3803 
3804 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3805 	if (!serial_driver) {
3806 		printk("%s can't allocate tty driver\n", driver_name);
3807 		return -ENOMEM;
3808 	}
3809 
3810 	/* Initialize the tty_driver structure */
3811 
3812 	serial_driver->driver_name = tty_driver_name;
3813 	serial_driver->name = tty_dev_prefix;
3814 	serial_driver->major = ttymajor;
3815 	serial_driver->minor_start = 64;
3816 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3817 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3818 	serial_driver->init_termios = tty_std_termios;
3819 	serial_driver->init_termios.c_cflag =
3820 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3821 	serial_driver->init_termios.c_ispeed = 9600;
3822 	serial_driver->init_termios.c_ospeed = 9600;
3823 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3824 	tty_set_operations(serial_driver, &ops);
3825 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3826 		DBGERR(("%s can't register serial driver\n", driver_name));
3827 		put_tty_driver(serial_driver);
3828 		serial_driver = NULL;
3829 		goto error;
3830 	}
3831 
3832 	printk(KERN_INFO "%s, tty major#%d\n",
3833 	       driver_name, serial_driver->major);
3834 
3835 	slgt_device_count = 0;
3836 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3837 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3838 		goto error;
3839 	}
3840 	pci_registered = true;
3841 
3842 	if (!slgt_device_list)
3843 		printk("%s no devices found\n",driver_name);
3844 
3845 	return 0;
3846 
3847 error:
3848 	slgt_cleanup();
3849 	return rc;
3850 }
3851 
3852 static void __exit slgt_exit(void)
3853 {
3854 	slgt_cleanup();
3855 }
3856 
3857 module_init(slgt_init);
3858 module_exit(slgt_exit);
3859 
3860 /*
3861  * register access routines
3862  */
3863 
3864 #define CALC_REGADDR() \
3865 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3866 	if (addr >= 0x80) \
3867 		reg_addr += (info->port_num) * 32; \
3868 	else if (addr >= 0x40)	\
3869 		reg_addr += (info->port_num) * 16;
3870 
3871 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3872 {
3873 	CALC_REGADDR();
3874 	return readb((void __iomem *)reg_addr);
3875 }
3876 
3877 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3878 {
3879 	CALC_REGADDR();
3880 	writeb(value, (void __iomem *)reg_addr);
3881 }
3882 
3883 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3884 {
3885 	CALC_REGADDR();
3886 	return readw((void __iomem *)reg_addr);
3887 }
3888 
3889 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3890 {
3891 	CALC_REGADDR();
3892 	writew(value, (void __iomem *)reg_addr);
3893 }
3894 
3895 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3896 {
3897 	CALC_REGADDR();
3898 	return readl((void __iomem *)reg_addr);
3899 }
3900 
3901 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3902 {
3903 	CALC_REGADDR();
3904 	writel(value, (void __iomem *)reg_addr);
3905 }
3906 
3907 static void rdma_reset(struct slgt_info *info)
3908 {
3909 	unsigned int i;
3910 
3911 	/* set reset bit */
3912 	wr_reg32(info, RDCSR, BIT1);
3913 
3914 	/* wait for enable bit cleared */
3915 	for(i=0 ; i < 1000 ; i++)
3916 		if (!(rd_reg32(info, RDCSR) & BIT0))
3917 			break;
3918 }
3919 
3920 static void tdma_reset(struct slgt_info *info)
3921 {
3922 	unsigned int i;
3923 
3924 	/* set reset bit */
3925 	wr_reg32(info, TDCSR, BIT1);
3926 
3927 	/* wait for enable bit cleared */
3928 	for(i=0 ; i < 1000 ; i++)
3929 		if (!(rd_reg32(info, TDCSR) & BIT0))
3930 			break;
3931 }
3932 
3933 /*
3934  * enable internal loopback
3935  * TxCLK and RxCLK are generated from BRG
3936  * and TxD is looped back to RxD internally.
3937  */
3938 static void enable_loopback(struct slgt_info *info)
3939 {
3940 	/* SCR (serial control) BIT2=loopback enable */
3941 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3942 
3943 	if (info->params.mode != MGSL_MODE_ASYNC) {
3944 		/* CCR (clock control)
3945 		 * 07..05  tx clock source (010 = BRG)
3946 		 * 04..02  rx clock source (010 = BRG)
3947 		 * 01      auxclk enable   (0 = disable)
3948 		 * 00      BRG enable      (1 = enable)
3949 		 *
3950 		 * 0100 1001
3951 		 */
3952 		wr_reg8(info, CCR, 0x49);
3953 
3954 		/* set speed if available, otherwise use default */
3955 		if (info->params.clock_speed)
3956 			set_rate(info, info->params.clock_speed);
3957 		else
3958 			set_rate(info, 3686400);
3959 	}
3960 }
3961 
3962 /*
3963  *  set baud rate generator to specified rate
3964  */
3965 static void set_rate(struct slgt_info *info, u32 rate)
3966 {
3967 	unsigned int div;
3968 	unsigned int osc = info->base_clock;
3969 
3970 	/* div = osc/rate - 1
3971 	 *
3972 	 * Round div up if osc/rate is not integer to
3973 	 * force to next slowest rate.
3974 	 */
3975 
3976 	if (rate) {
3977 		div = osc/rate;
3978 		if (!(osc % rate) && div)
3979 			div--;
3980 		wr_reg16(info, BDR, (unsigned short)div);
3981 	}
3982 }
3983 
3984 static void rx_stop(struct slgt_info *info)
3985 {
3986 	unsigned short val;
3987 
3988 	/* disable and reset receiver */
3989 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3990 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3991 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3992 
3993 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3994 
3995 	/* clear pending rx interrupts */
3996 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3997 
3998 	rdma_reset(info);
3999 
4000 	info->rx_enabled = false;
4001 	info->rx_restart = false;
4002 }
4003 
4004 static void rx_start(struct slgt_info *info)
4005 {
4006 	unsigned short val;
4007 
4008 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
4009 
4010 	/* clear pending rx overrun IRQ */
4011 	wr_reg16(info, SSR, IRQ_RXOVER);
4012 
4013 	/* reset and disable receiver */
4014 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
4015 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
4016 	wr_reg16(info, RCR, val);                  /* clear reset bit */
4017 
4018 	rdma_reset(info);
4019 	reset_rbufs(info);
4020 
4021 	if (info->rx_pio) {
4022 		/* rx request when rx FIFO not empty */
4023 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
4024 		slgt_irq_on(info, IRQ_RXDATA);
4025 		if (info->params.mode == MGSL_MODE_ASYNC) {
4026 			/* enable saving of rx status */
4027 			wr_reg32(info, RDCSR, BIT6);
4028 		}
4029 	} else {
4030 		/* rx request when rx FIFO half full */
4031 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
4032 		/* set 1st descriptor address */
4033 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
4034 
4035 		if (info->params.mode != MGSL_MODE_ASYNC) {
4036 			/* enable rx DMA and DMA interrupt */
4037 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
4038 		} else {
4039 			/* enable saving of rx status, rx DMA and DMA interrupt */
4040 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
4041 		}
4042 	}
4043 
4044 	slgt_irq_on(info, IRQ_RXOVER);
4045 
4046 	/* enable receiver */
4047 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
4048 
4049 	info->rx_restart = false;
4050 	info->rx_enabled = true;
4051 }
4052 
4053 static void tx_start(struct slgt_info *info)
4054 {
4055 	if (!info->tx_enabled) {
4056 		wr_reg16(info, TCR,
4057 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
4058 		info->tx_enabled = true;
4059 	}
4060 
4061 	if (desc_count(info->tbufs[info->tbuf_start])) {
4062 		info->drop_rts_on_tx_done = false;
4063 
4064 		if (info->params.mode != MGSL_MODE_ASYNC) {
4065 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
4066 				get_signals(info);
4067 				if (!(info->signals & SerialSignal_RTS)) {
4068 					info->signals |= SerialSignal_RTS;
4069 					set_signals(info);
4070 					info->drop_rts_on_tx_done = true;
4071 				}
4072 			}
4073 
4074 			slgt_irq_off(info, IRQ_TXDATA);
4075 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
4076 			/* clear tx idle and underrun status bits */
4077 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4078 		} else {
4079 			slgt_irq_off(info, IRQ_TXDATA);
4080 			slgt_irq_on(info, IRQ_TXIDLE);
4081 			/* clear tx idle status bit */
4082 			wr_reg16(info, SSR, IRQ_TXIDLE);
4083 		}
4084 		/* set 1st descriptor address and start DMA */
4085 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
4086 		wr_reg32(info, TDCSR, BIT2 + BIT0);
4087 		info->tx_active = true;
4088 	}
4089 }
4090 
4091 static void tx_stop(struct slgt_info *info)
4092 {
4093 	unsigned short val;
4094 
4095 	del_timer(&info->tx_timer);
4096 
4097 	tdma_reset(info);
4098 
4099 	/* reset and disable transmitter */
4100 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
4101 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
4102 
4103 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
4104 
4105 	/* clear tx idle and underrun status bit */
4106 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4107 
4108 	reset_tbufs(info);
4109 
4110 	info->tx_enabled = false;
4111 	info->tx_active = false;
4112 }
4113 
4114 static void reset_port(struct slgt_info *info)
4115 {
4116 	if (!info->reg_addr)
4117 		return;
4118 
4119 	tx_stop(info);
4120 	rx_stop(info);
4121 
4122 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4123 	set_signals(info);
4124 
4125 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4126 }
4127 
4128 static void reset_adapter(struct slgt_info *info)
4129 {
4130 	int i;
4131 	for (i=0; i < info->port_count; ++i) {
4132 		if (info->port_array[i])
4133 			reset_port(info->port_array[i]);
4134 	}
4135 }
4136 
4137 static void async_mode(struct slgt_info *info)
4138 {
4139   	unsigned short val;
4140 
4141 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4142 	tx_stop(info);
4143 	rx_stop(info);
4144 
4145 	/* TCR (tx control)
4146 	 *
4147 	 * 15..13  mode, 010=async
4148 	 * 12..10  encoding, 000=NRZ
4149 	 * 09      parity enable
4150 	 * 08      1=odd parity, 0=even parity
4151 	 * 07      1=RTS driver control
4152 	 * 06      1=break enable
4153 	 * 05..04  character length
4154 	 *         00=5 bits
4155 	 *         01=6 bits
4156 	 *         10=7 bits
4157 	 *         11=8 bits
4158 	 * 03      0=1 stop bit, 1=2 stop bits
4159 	 * 02      reset
4160 	 * 01      enable
4161 	 * 00      auto-CTS enable
4162 	 */
4163 	val = 0x4000;
4164 
4165 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4166 		val |= BIT7;
4167 
4168 	if (info->params.parity != ASYNC_PARITY_NONE) {
4169 		val |= BIT9;
4170 		if (info->params.parity == ASYNC_PARITY_ODD)
4171 			val |= BIT8;
4172 	}
4173 
4174 	switch (info->params.data_bits)
4175 	{
4176 	case 6: val |= BIT4; break;
4177 	case 7: val |= BIT5; break;
4178 	case 8: val |= BIT5 + BIT4; break;
4179 	}
4180 
4181 	if (info->params.stop_bits != 1)
4182 		val |= BIT3;
4183 
4184 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4185 		val |= BIT0;
4186 
4187 	wr_reg16(info, TCR, val);
4188 
4189 	/* RCR (rx control)
4190 	 *
4191 	 * 15..13  mode, 010=async
4192 	 * 12..10  encoding, 000=NRZ
4193 	 * 09      parity enable
4194 	 * 08      1=odd parity, 0=even parity
4195 	 * 07..06  reserved, must be 0
4196 	 * 05..04  character length
4197 	 *         00=5 bits
4198 	 *         01=6 bits
4199 	 *         10=7 bits
4200 	 *         11=8 bits
4201 	 * 03      reserved, must be zero
4202 	 * 02      reset
4203 	 * 01      enable
4204 	 * 00      auto-DCD enable
4205 	 */
4206 	val = 0x4000;
4207 
4208 	if (info->params.parity != ASYNC_PARITY_NONE) {
4209 		val |= BIT9;
4210 		if (info->params.parity == ASYNC_PARITY_ODD)
4211 			val |= BIT8;
4212 	}
4213 
4214 	switch (info->params.data_bits)
4215 	{
4216 	case 6: val |= BIT4; break;
4217 	case 7: val |= BIT5; break;
4218 	case 8: val |= BIT5 + BIT4; break;
4219 	}
4220 
4221 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4222 		val |= BIT0;
4223 
4224 	wr_reg16(info, RCR, val);
4225 
4226 	/* CCR (clock control)
4227 	 *
4228 	 * 07..05  011 = tx clock source is BRG/16
4229 	 * 04..02  010 = rx clock source is BRG
4230 	 * 01      0 = auxclk disabled
4231 	 * 00      1 = BRG enabled
4232 	 *
4233 	 * 0110 1001
4234 	 */
4235 	wr_reg8(info, CCR, 0x69);
4236 
4237 	msc_set_vcr(info);
4238 
4239 	/* SCR (serial control)
4240 	 *
4241 	 * 15  1=tx req on FIFO half empty
4242 	 * 14  1=rx req on FIFO half full
4243 	 * 13  tx data  IRQ enable
4244 	 * 12  tx idle  IRQ enable
4245 	 * 11  rx break on IRQ enable
4246 	 * 10  rx data  IRQ enable
4247 	 * 09  rx break off IRQ enable
4248 	 * 08  overrun  IRQ enable
4249 	 * 07  DSR      IRQ enable
4250 	 * 06  CTS      IRQ enable
4251 	 * 05  DCD      IRQ enable
4252 	 * 04  RI       IRQ enable
4253 	 * 03  0=16x sampling, 1=8x sampling
4254 	 * 02  1=txd->rxd internal loopback enable
4255 	 * 01  reserved, must be zero
4256 	 * 00  1=master IRQ enable
4257 	 */
4258 	val = BIT15 + BIT14 + BIT0;
4259 	/* JCR[8] : 1 = x8 async mode feature available */
4260 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4261 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4262 	     (info->base_clock % (info->params.data_rate * 16)))) {
4263 		/* use 8x sampling */
4264 		val |= BIT3;
4265 		set_rate(info, info->params.data_rate * 8);
4266 	} else {
4267 		/* use 16x sampling */
4268 		set_rate(info, info->params.data_rate * 16);
4269 	}
4270 	wr_reg16(info, SCR, val);
4271 
4272 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4273 
4274 	if (info->params.loopback)
4275 		enable_loopback(info);
4276 }
4277 
4278 static void sync_mode(struct slgt_info *info)
4279 {
4280 	unsigned short val;
4281 
4282 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4283 	tx_stop(info);
4284 	rx_stop(info);
4285 
4286 	/* TCR (tx control)
4287 	 *
4288 	 * 15..13  mode
4289 	 *         000=HDLC/SDLC
4290 	 *         001=raw bit synchronous
4291 	 *         010=asynchronous/isochronous
4292 	 *         011=monosync byte synchronous
4293 	 *         100=bisync byte synchronous
4294 	 *         101=xsync byte synchronous
4295 	 * 12..10  encoding
4296 	 * 09      CRC enable
4297 	 * 08      CRC32
4298 	 * 07      1=RTS driver control
4299 	 * 06      preamble enable
4300 	 * 05..04  preamble length
4301 	 * 03      share open/close flag
4302 	 * 02      reset
4303 	 * 01      enable
4304 	 * 00      auto-CTS enable
4305 	 */
4306 	val = BIT2;
4307 
4308 	switch(info->params.mode) {
4309 	case MGSL_MODE_XSYNC:
4310 		val |= BIT15 + BIT13;
4311 		break;
4312 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4313 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4314 	case MGSL_MODE_RAW:      val |= BIT13; break;
4315 	}
4316 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4317 		val |= BIT7;
4318 
4319 	switch(info->params.encoding)
4320 	{
4321 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4322 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4323 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4324 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4325 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4326 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4327 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4328 	}
4329 
4330 	switch (info->params.crc_type & HDLC_CRC_MASK)
4331 	{
4332 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4333 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4334 	}
4335 
4336 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4337 		val |= BIT6;
4338 
4339 	switch (info->params.preamble_length)
4340 	{
4341 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4342 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4343 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4344 	}
4345 
4346 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4347 		val |= BIT0;
4348 
4349 	wr_reg16(info, TCR, val);
4350 
4351 	/* TPR (transmit preamble) */
4352 
4353 	switch (info->params.preamble)
4354 	{
4355 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4356 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4357 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4358 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4359 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4360 	default:                          val = 0x7e; break;
4361 	}
4362 	wr_reg8(info, TPR, (unsigned char)val);
4363 
4364 	/* RCR (rx control)
4365 	 *
4366 	 * 15..13  mode
4367 	 *         000=HDLC/SDLC
4368 	 *         001=raw bit synchronous
4369 	 *         010=asynchronous/isochronous
4370 	 *         011=monosync byte synchronous
4371 	 *         100=bisync byte synchronous
4372 	 *         101=xsync byte synchronous
4373 	 * 12..10  encoding
4374 	 * 09      CRC enable
4375 	 * 08      CRC32
4376 	 * 07..03  reserved, must be 0
4377 	 * 02      reset
4378 	 * 01      enable
4379 	 * 00      auto-DCD enable
4380 	 */
4381 	val = 0;
4382 
4383 	switch(info->params.mode) {
4384 	case MGSL_MODE_XSYNC:
4385 		val |= BIT15 + BIT13;
4386 		break;
4387 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4388 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4389 	case MGSL_MODE_RAW:      val |= BIT13; break;
4390 	}
4391 
4392 	switch(info->params.encoding)
4393 	{
4394 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4395 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4396 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4397 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4398 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4399 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4400 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4401 	}
4402 
4403 	switch (info->params.crc_type & HDLC_CRC_MASK)
4404 	{
4405 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4406 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4407 	}
4408 
4409 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4410 		val |= BIT0;
4411 
4412 	wr_reg16(info, RCR, val);
4413 
4414 	/* CCR (clock control)
4415 	 *
4416 	 * 07..05  tx clock source
4417 	 * 04..02  rx clock source
4418 	 * 01      auxclk enable
4419 	 * 00      BRG enable
4420 	 */
4421 	val = 0;
4422 
4423 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4424 	{
4425 		// when RxC source is DPLL, BRG generates 16X DPLL
4426 		// reference clock, so take TxC from BRG/16 to get
4427 		// transmit clock at actual data rate
4428 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4429 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4430 		else
4431 			val |= BIT6;	/* 010, txclk = BRG */
4432 	}
4433 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4434 		val |= BIT7;	/* 100, txclk = DPLL Input */
4435 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4436 		val |= BIT5;	/* 001, txclk = RXC Input */
4437 
4438 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4439 		val |= BIT3;	/* 010, rxclk = BRG */
4440 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4441 		val |= BIT4;	/* 100, rxclk = DPLL */
4442 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4443 		val |= BIT2;	/* 001, rxclk = TXC Input */
4444 
4445 	if (info->params.clock_speed)
4446 		val |= BIT1 + BIT0;
4447 
4448 	wr_reg8(info, CCR, (unsigned char)val);
4449 
4450 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4451 	{
4452 		// program DPLL mode
4453 		switch(info->params.encoding)
4454 		{
4455 		case HDLC_ENCODING_BIPHASE_MARK:
4456 		case HDLC_ENCODING_BIPHASE_SPACE:
4457 			val = BIT7; break;
4458 		case HDLC_ENCODING_BIPHASE_LEVEL:
4459 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4460 			val = BIT7 + BIT6; break;
4461 		default: val = BIT6;	// NRZ encodings
4462 		}
4463 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4464 
4465 		// DPLL requires a 16X reference clock from BRG
4466 		set_rate(info, info->params.clock_speed * 16);
4467 	}
4468 	else
4469 		set_rate(info, info->params.clock_speed);
4470 
4471 	tx_set_idle(info);
4472 
4473 	msc_set_vcr(info);
4474 
4475 	/* SCR (serial control)
4476 	 *
4477 	 * 15  1=tx req on FIFO half empty
4478 	 * 14  1=rx req on FIFO half full
4479 	 * 13  tx data  IRQ enable
4480 	 * 12  tx idle  IRQ enable
4481 	 * 11  underrun IRQ enable
4482 	 * 10  rx data  IRQ enable
4483 	 * 09  rx idle  IRQ enable
4484 	 * 08  overrun  IRQ enable
4485 	 * 07  DSR      IRQ enable
4486 	 * 06  CTS      IRQ enable
4487 	 * 05  DCD      IRQ enable
4488 	 * 04  RI       IRQ enable
4489 	 * 03  reserved, must be zero
4490 	 * 02  1=txd->rxd internal loopback enable
4491 	 * 01  reserved, must be zero
4492 	 * 00  1=master IRQ enable
4493 	 */
4494 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4495 
4496 	if (info->params.loopback)
4497 		enable_loopback(info);
4498 }
4499 
4500 /*
4501  *  set transmit idle mode
4502  */
4503 static void tx_set_idle(struct slgt_info *info)
4504 {
4505 	unsigned char val;
4506 	unsigned short tcr;
4507 
4508 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4509 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4510 	 */
4511 	tcr = rd_reg16(info, TCR);
4512 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4513 		/* disable preamble, set idle size to 16 bits */
4514 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4515 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4516 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4517 	} else if (!(tcr & BIT6)) {
4518 		/* preamble is disabled, set idle size to 8 bits */
4519 		tcr &= ~(BIT5 + BIT4);
4520 	}
4521 	wr_reg16(info, TCR, tcr);
4522 
4523 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4524 		/* LSB of custom tx idle specified in tx idle register */
4525 		val = (unsigned char)(info->idle_mode & 0xff);
4526 	} else {
4527 		/* standard 8 bit idle patterns */
4528 		switch(info->idle_mode)
4529 		{
4530 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4531 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4532 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4533 		case HDLC_TXIDLE_ZEROS:
4534 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4535 		default:                         val = 0xff;
4536 		}
4537 	}
4538 
4539 	wr_reg8(info, TIR, val);
4540 }
4541 
4542 /*
4543  * get state of V24 status (input) signals
4544  */
4545 static void get_signals(struct slgt_info *info)
4546 {
4547 	unsigned short status = rd_reg16(info, SSR);
4548 
4549 	/* clear all serial signals except RTS and DTR */
4550 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4551 
4552 	if (status & BIT3)
4553 		info->signals |= SerialSignal_DSR;
4554 	if (status & BIT2)
4555 		info->signals |= SerialSignal_CTS;
4556 	if (status & BIT1)
4557 		info->signals |= SerialSignal_DCD;
4558 	if (status & BIT0)
4559 		info->signals |= SerialSignal_RI;
4560 }
4561 
4562 /*
4563  * set V.24 Control Register based on current configuration
4564  */
4565 static void msc_set_vcr(struct slgt_info *info)
4566 {
4567 	unsigned char val = 0;
4568 
4569 	/* VCR (V.24 control)
4570 	 *
4571 	 * 07..04  serial IF select
4572 	 * 03      DTR
4573 	 * 02      RTS
4574 	 * 01      LL
4575 	 * 00      RL
4576 	 */
4577 
4578 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4579 	{
4580 	case MGSL_INTERFACE_RS232:
4581 		val |= BIT5; /* 0010 */
4582 		break;
4583 	case MGSL_INTERFACE_V35:
4584 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4585 		break;
4586 	case MGSL_INTERFACE_RS422:
4587 		val |= BIT6; /* 0100 */
4588 		break;
4589 	}
4590 
4591 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4592 		val |= BIT4;
4593 	if (info->signals & SerialSignal_DTR)
4594 		val |= BIT3;
4595 	if (info->signals & SerialSignal_RTS)
4596 		val |= BIT2;
4597 	if (info->if_mode & MGSL_INTERFACE_LL)
4598 		val |= BIT1;
4599 	if (info->if_mode & MGSL_INTERFACE_RL)
4600 		val |= BIT0;
4601 	wr_reg8(info, VCR, val);
4602 }
4603 
4604 /*
4605  * set state of V24 control (output) signals
4606  */
4607 static void set_signals(struct slgt_info *info)
4608 {
4609 	unsigned char val = rd_reg8(info, VCR);
4610 	if (info->signals & SerialSignal_DTR)
4611 		val |= BIT3;
4612 	else
4613 		val &= ~BIT3;
4614 	if (info->signals & SerialSignal_RTS)
4615 		val |= BIT2;
4616 	else
4617 		val &= ~BIT2;
4618 	wr_reg8(info, VCR, val);
4619 }
4620 
4621 /*
4622  * free range of receive DMA buffers (i to last)
4623  */
4624 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4625 {
4626 	int done = 0;
4627 
4628 	while(!done) {
4629 		/* reset current buffer for reuse */
4630 		info->rbufs[i].status = 0;
4631 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4632 		if (i == last)
4633 			done = 1;
4634 		if (++i == info->rbuf_count)
4635 			i = 0;
4636 	}
4637 	info->rbuf_current = i;
4638 }
4639 
4640 /*
4641  * mark all receive DMA buffers as free
4642  */
4643 static void reset_rbufs(struct slgt_info *info)
4644 {
4645 	free_rbufs(info, 0, info->rbuf_count - 1);
4646 	info->rbuf_fill_index = 0;
4647 	info->rbuf_fill_count = 0;
4648 }
4649 
4650 /*
4651  * pass receive HDLC frame to upper layer
4652  *
4653  * return true if frame available, otherwise false
4654  */
4655 static bool rx_get_frame(struct slgt_info *info)
4656 {
4657 	unsigned int start, end;
4658 	unsigned short status;
4659 	unsigned int framesize = 0;
4660 	unsigned long flags;
4661 	struct tty_struct *tty = info->port.tty;
4662 	unsigned char addr_field = 0xff;
4663 	unsigned int crc_size = 0;
4664 
4665 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4666 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4667 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4668 	}
4669 
4670 check_again:
4671 
4672 	framesize = 0;
4673 	addr_field = 0xff;
4674 	start = end = info->rbuf_current;
4675 
4676 	for (;;) {
4677 		if (!desc_complete(info->rbufs[end]))
4678 			goto cleanup;
4679 
4680 		if (framesize == 0 && info->params.addr_filter != 0xff)
4681 			addr_field = info->rbufs[end].buf[0];
4682 
4683 		framesize += desc_count(info->rbufs[end]);
4684 
4685 		if (desc_eof(info->rbufs[end]))
4686 			break;
4687 
4688 		if (++end == info->rbuf_count)
4689 			end = 0;
4690 
4691 		if (end == info->rbuf_current) {
4692 			if (info->rx_enabled){
4693 				spin_lock_irqsave(&info->lock,flags);
4694 				rx_start(info);
4695 				spin_unlock_irqrestore(&info->lock,flags);
4696 			}
4697 			goto cleanup;
4698 		}
4699 	}
4700 
4701 	/* status
4702 	 *
4703 	 * 15      buffer complete
4704 	 * 14..06  reserved
4705 	 * 05..04  residue
4706 	 * 02      eof (end of frame)
4707 	 * 01      CRC error
4708 	 * 00      abort
4709 	 */
4710 	status = desc_status(info->rbufs[end]);
4711 
4712 	/* ignore CRC bit if not using CRC (bit is undefined) */
4713 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4714 		status &= ~BIT1;
4715 
4716 	if (framesize == 0 ||
4717 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4718 		free_rbufs(info, start, end);
4719 		goto check_again;
4720 	}
4721 
4722 	if (framesize < (2 + crc_size) || status & BIT0) {
4723 		info->icount.rxshort++;
4724 		framesize = 0;
4725 	} else if (status & BIT1) {
4726 		info->icount.rxcrc++;
4727 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4728 			framesize = 0;
4729 	}
4730 
4731 #if SYNCLINK_GENERIC_HDLC
4732 	if (framesize == 0) {
4733 		info->netdev->stats.rx_errors++;
4734 		info->netdev->stats.rx_frame_errors++;
4735 	}
4736 #endif
4737 
4738 	DBGBH(("%s rx frame status=%04X size=%d\n",
4739 		info->device_name, status, framesize));
4740 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4741 
4742 	if (framesize) {
4743 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4744 			framesize -= crc_size;
4745 			crc_size = 0;
4746 		}
4747 
4748 		if (framesize > info->max_frame_size + crc_size)
4749 			info->icount.rxlong++;
4750 		else {
4751 			/* copy dma buffer(s) to contiguous temp buffer */
4752 			int copy_count = framesize;
4753 			int i = start;
4754 			unsigned char *p = info->tmp_rbuf;
4755 			info->tmp_rbuf_count = framesize;
4756 
4757 			info->icount.rxok++;
4758 
4759 			while(copy_count) {
4760 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4761 				memcpy(p, info->rbufs[i].buf, partial_count);
4762 				p += partial_count;
4763 				copy_count -= partial_count;
4764 				if (++i == info->rbuf_count)
4765 					i = 0;
4766 			}
4767 
4768 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4769 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4770 				framesize++;
4771 			}
4772 
4773 #if SYNCLINK_GENERIC_HDLC
4774 			if (info->netcount)
4775 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4776 			else
4777 #endif
4778 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4779 		}
4780 	}
4781 	free_rbufs(info, start, end);
4782 	return true;
4783 
4784 cleanup:
4785 	return false;
4786 }
4787 
4788 /*
4789  * pass receive buffer (RAW synchronous mode) to tty layer
4790  * return true if buffer available, otherwise false
4791  */
4792 static bool rx_get_buf(struct slgt_info *info)
4793 {
4794 	unsigned int i = info->rbuf_current;
4795 	unsigned int count;
4796 
4797 	if (!desc_complete(info->rbufs[i]))
4798 		return false;
4799 	count = desc_count(info->rbufs[i]);
4800 	switch(info->params.mode) {
4801 	case MGSL_MODE_MONOSYNC:
4802 	case MGSL_MODE_BISYNC:
4803 	case MGSL_MODE_XSYNC:
4804 		/* ignore residue in byte synchronous modes */
4805 		if (desc_residue(info->rbufs[i]))
4806 			count--;
4807 		break;
4808 	}
4809 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4810 	DBGINFO(("rx_get_buf size=%d\n", count));
4811 	if (count)
4812 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4813 				  info->flag_buf, count);
4814 	free_rbufs(info, i, i);
4815 	return true;
4816 }
4817 
4818 static void reset_tbufs(struct slgt_info *info)
4819 {
4820 	unsigned int i;
4821 	info->tbuf_current = 0;
4822 	for (i=0 ; i < info->tbuf_count ; i++) {
4823 		info->tbufs[i].status = 0;
4824 		info->tbufs[i].count  = 0;
4825 	}
4826 }
4827 
4828 /*
4829  * return number of free transmit DMA buffers
4830  */
4831 static unsigned int free_tbuf_count(struct slgt_info *info)
4832 {
4833 	unsigned int count = 0;
4834 	unsigned int i = info->tbuf_current;
4835 
4836 	do
4837 	{
4838 		if (desc_count(info->tbufs[i]))
4839 			break; /* buffer in use */
4840 		++count;
4841 		if (++i == info->tbuf_count)
4842 			i=0;
4843 	} while (i != info->tbuf_current);
4844 
4845 	/* if tx DMA active, last zero count buffer is in use */
4846 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4847 		--count;
4848 
4849 	return count;
4850 }
4851 
4852 /*
4853  * return number of bytes in unsent transmit DMA buffers
4854  * and the serial controller tx FIFO
4855  */
4856 static unsigned int tbuf_bytes(struct slgt_info *info)
4857 {
4858 	unsigned int total_count = 0;
4859 	unsigned int i = info->tbuf_current;
4860 	unsigned int reg_value;
4861 	unsigned int count;
4862 	unsigned int active_buf_count = 0;
4863 
4864 	/*
4865 	 * Add descriptor counts for all tx DMA buffers.
4866 	 * If count is zero (cleared by DMA controller after read),
4867 	 * the buffer is complete or is actively being read from.
4868 	 *
4869 	 * Record buf_count of last buffer with zero count starting
4870 	 * from current ring position. buf_count is mirror
4871 	 * copy of count and is not cleared by serial controller.
4872 	 * If DMA controller is active, that buffer is actively
4873 	 * being read so add to total.
4874 	 */
4875 	do {
4876 		count = desc_count(info->tbufs[i]);
4877 		if (count)
4878 			total_count += count;
4879 		else if (!total_count)
4880 			active_buf_count = info->tbufs[i].buf_count;
4881 		if (++i == info->tbuf_count)
4882 			i = 0;
4883 	} while (i != info->tbuf_current);
4884 
4885 	/* read tx DMA status register */
4886 	reg_value = rd_reg32(info, TDCSR);
4887 
4888 	/* if tx DMA active, last zero count buffer is in use */
4889 	if (reg_value & BIT0)
4890 		total_count += active_buf_count;
4891 
4892 	/* add tx FIFO count = reg_value[15..8] */
4893 	total_count += (reg_value >> 8) & 0xff;
4894 
4895 	/* if transmitter active add one byte for shift register */
4896 	if (info->tx_active)
4897 		total_count++;
4898 
4899 	return total_count;
4900 }
4901 
4902 /*
4903  * load data into transmit DMA buffer ring and start transmitter if needed
4904  * return true if data accepted, otherwise false (buffers full)
4905  */
4906 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4907 {
4908 	unsigned short count;
4909 	unsigned int i;
4910 	struct slgt_desc *d;
4911 
4912 	/* check required buffer space */
4913 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4914 		return false;
4915 
4916 	DBGDATA(info, buf, size, "tx");
4917 
4918 	/*
4919 	 * copy data to one or more DMA buffers in circular ring
4920 	 * tbuf_start   = first buffer for this data
4921 	 * tbuf_current = next free buffer
4922 	 *
4923 	 * Copy all data before making data visible to DMA controller by
4924 	 * setting descriptor count of the first buffer.
4925 	 * This prevents an active DMA controller from reading the first DMA
4926 	 * buffers of a frame and stopping before the final buffers are filled.
4927 	 */
4928 
4929 	info->tbuf_start = i = info->tbuf_current;
4930 
4931 	while (size) {
4932 		d = &info->tbufs[i];
4933 
4934 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4935 		memcpy(d->buf, buf, count);
4936 
4937 		size -= count;
4938 		buf  += count;
4939 
4940 		/*
4941 		 * set EOF bit for last buffer of HDLC frame or
4942 		 * for every buffer in raw mode
4943 		 */
4944 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4945 		    info->params.mode == MGSL_MODE_RAW)
4946 			set_desc_eof(*d, 1);
4947 		else
4948 			set_desc_eof(*d, 0);
4949 
4950 		/* set descriptor count for all but first buffer */
4951 		if (i != info->tbuf_start)
4952 			set_desc_count(*d, count);
4953 		d->buf_count = count;
4954 
4955 		if (++i == info->tbuf_count)
4956 			i = 0;
4957 	}
4958 
4959 	info->tbuf_current = i;
4960 
4961 	/* set first buffer count to make new data visible to DMA controller */
4962 	d = &info->tbufs[info->tbuf_start];
4963 	set_desc_count(*d, d->buf_count);
4964 
4965 	/* start transmitter if needed and update transmit timeout */
4966 	if (!info->tx_active)
4967 		tx_start(info);
4968 	update_tx_timer(info);
4969 
4970 	return true;
4971 }
4972 
4973 static int register_test(struct slgt_info *info)
4974 {
4975 	static unsigned short patterns[] =
4976 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4977 	static unsigned int count = ARRAY_SIZE(patterns);
4978 	unsigned int i;
4979 	int rc = 0;
4980 
4981 	for (i=0 ; i < count ; i++) {
4982 		wr_reg16(info, TIR, patterns[i]);
4983 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4984 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4985 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4986 			rc = -ENODEV;
4987 			break;
4988 		}
4989 	}
4990 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4991 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4992 	return rc;
4993 }
4994 
4995 static int irq_test(struct slgt_info *info)
4996 {
4997 	unsigned long timeout;
4998 	unsigned long flags;
4999 	struct tty_struct *oldtty = info->port.tty;
5000 	u32 speed = info->params.data_rate;
5001 
5002 	info->params.data_rate = 921600;
5003 	info->port.tty = NULL;
5004 
5005 	spin_lock_irqsave(&info->lock, flags);
5006 	async_mode(info);
5007 	slgt_irq_on(info, IRQ_TXIDLE);
5008 
5009 	/* enable transmitter */
5010 	wr_reg16(info, TCR,
5011 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
5012 
5013 	/* write one byte and wait for tx idle */
5014 	wr_reg16(info, TDR, 0);
5015 
5016 	/* assume failure */
5017 	info->init_error = DiagStatus_IrqFailure;
5018 	info->irq_occurred = false;
5019 
5020 	spin_unlock_irqrestore(&info->lock, flags);
5021 
5022 	timeout=100;
5023 	while(timeout-- && !info->irq_occurred)
5024 		msleep_interruptible(10);
5025 
5026 	spin_lock_irqsave(&info->lock,flags);
5027 	reset_port(info);
5028 	spin_unlock_irqrestore(&info->lock,flags);
5029 
5030 	info->params.data_rate = speed;
5031 	info->port.tty = oldtty;
5032 
5033 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
5034 	return info->irq_occurred ? 0 : -ENODEV;
5035 }
5036 
5037 static int loopback_test_rx(struct slgt_info *info)
5038 {
5039 	unsigned char *src, *dest;
5040 	int count;
5041 
5042 	if (desc_complete(info->rbufs[0])) {
5043 		count = desc_count(info->rbufs[0]);
5044 		src   = info->rbufs[0].buf;
5045 		dest  = info->tmp_rbuf;
5046 
5047 		for( ; count ; count-=2, src+=2) {
5048 			/* src=data byte (src+1)=status byte */
5049 			if (!(*(src+1) & (BIT9 + BIT8))) {
5050 				*dest = *src;
5051 				dest++;
5052 				info->tmp_rbuf_count++;
5053 			}
5054 		}
5055 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
5056 		return 1;
5057 	}
5058 	return 0;
5059 }
5060 
5061 static int loopback_test(struct slgt_info *info)
5062 {
5063 #define TESTFRAMESIZE 20
5064 
5065 	unsigned long timeout;
5066 	u16 count = TESTFRAMESIZE;
5067 	unsigned char buf[TESTFRAMESIZE];
5068 	int rc = -ENODEV;
5069 	unsigned long flags;
5070 
5071 	struct tty_struct *oldtty = info->port.tty;
5072 	MGSL_PARAMS params;
5073 
5074 	memcpy(&params, &info->params, sizeof(params));
5075 
5076 	info->params.mode = MGSL_MODE_ASYNC;
5077 	info->params.data_rate = 921600;
5078 	info->params.loopback = 1;
5079 	info->port.tty = NULL;
5080 
5081 	/* build and send transmit frame */
5082 	for (count = 0; count < TESTFRAMESIZE; ++count)
5083 		buf[count] = (unsigned char)count;
5084 
5085 	info->tmp_rbuf_count = 0;
5086 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
5087 
5088 	/* program hardware for HDLC and enabled receiver */
5089 	spin_lock_irqsave(&info->lock,flags);
5090 	async_mode(info);
5091 	rx_start(info);
5092 	tx_load(info, buf, count);
5093 	spin_unlock_irqrestore(&info->lock, flags);
5094 
5095 	/* wait for receive complete */
5096 	for (timeout = 100; timeout; --timeout) {
5097 		msleep_interruptible(10);
5098 		if (loopback_test_rx(info)) {
5099 			rc = 0;
5100 			break;
5101 		}
5102 	}
5103 
5104 	/* verify received frame length and contents */
5105 	if (!rc && (info->tmp_rbuf_count != count ||
5106 		  memcmp(buf, info->tmp_rbuf, count))) {
5107 		rc = -ENODEV;
5108 	}
5109 
5110 	spin_lock_irqsave(&info->lock,flags);
5111 	reset_adapter(info);
5112 	spin_unlock_irqrestore(&info->lock,flags);
5113 
5114 	memcpy(&info->params, &params, sizeof(info->params));
5115 	info->port.tty = oldtty;
5116 
5117 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5118 	return rc;
5119 }
5120 
5121 static int adapter_test(struct slgt_info *info)
5122 {
5123 	DBGINFO(("testing %s\n", info->device_name));
5124 	if (register_test(info) < 0) {
5125 		printk("register test failure %s addr=%08X\n",
5126 			info->device_name, info->phys_reg_addr);
5127 	} else if (irq_test(info) < 0) {
5128 		printk("IRQ test failure %s IRQ=%d\n",
5129 			info->device_name, info->irq_level);
5130 	} else if (loopback_test(info) < 0) {
5131 		printk("loopback test failure %s\n", info->device_name);
5132 	}
5133 	return info->init_error;
5134 }
5135 
5136 /*
5137  * transmit timeout handler
5138  */
5139 static void tx_timeout(unsigned long context)
5140 {
5141 	struct slgt_info *info = (struct slgt_info*)context;
5142 	unsigned long flags;
5143 
5144 	DBGINFO(("%s tx_timeout\n", info->device_name));
5145 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5146 		info->icount.txtimeout++;
5147 	}
5148 	spin_lock_irqsave(&info->lock,flags);
5149 	tx_stop(info);
5150 	spin_unlock_irqrestore(&info->lock,flags);
5151 
5152 #if SYNCLINK_GENERIC_HDLC
5153 	if (info->netcount)
5154 		hdlcdev_tx_done(info);
5155 	else
5156 #endif
5157 		bh_transmit(info);
5158 }
5159 
5160 /*
5161  * receive buffer polling timer
5162  */
5163 static void rx_timeout(unsigned long context)
5164 {
5165 	struct slgt_info *info = (struct slgt_info*)context;
5166 	unsigned long flags;
5167 
5168 	DBGINFO(("%s rx_timeout\n", info->device_name));
5169 	spin_lock_irqsave(&info->lock, flags);
5170 	info->pending_bh |= BH_RECEIVE;
5171 	spin_unlock_irqrestore(&info->lock, flags);
5172 	bh_handler(&info->task);
5173 }
5174 
5175