xref: /linux/drivers/tty/synclink_gt.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
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 *slgt_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 	mutex_lock(&info->port.mutex);
676 	info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
677 
678 	spin_lock_irqsave(&info->netlock, flags);
679 	if (info->netcount) {
680 		retval = -EBUSY;
681 		spin_unlock_irqrestore(&info->netlock, flags);
682 		mutex_unlock(&info->port.mutex);
683 		goto cleanup;
684 	}
685 	info->port.count++;
686 	spin_unlock_irqrestore(&info->netlock, flags);
687 
688 	if (info->port.count == 1) {
689 		/* 1st open on this device, init hardware */
690 		retval = startup(info);
691 		if (retval < 0) {
692 			mutex_unlock(&info->port.mutex);
693 			goto cleanup;
694 		}
695 	}
696 	mutex_unlock(&info->port.mutex);
697 	retval = block_til_ready(tty, filp, info);
698 	if (retval) {
699 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
700 		goto cleanup;
701 	}
702 
703 	retval = 0;
704 
705 cleanup:
706 	if (retval) {
707 		if (tty->count == 1)
708 			info->port.tty = NULL; /* tty layer will release tty struct */
709 		if(info->port.count)
710 			info->port.count--;
711 	}
712 
713 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
714 	return retval;
715 }
716 
717 static void close(struct tty_struct *tty, struct file *filp)
718 {
719 	struct slgt_info *info = tty->driver_data;
720 
721 	if (sanity_check(info, tty->name, "close"))
722 		return;
723 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
724 
725 	if (tty_port_close_start(&info->port, tty, filp) == 0)
726 		goto cleanup;
727 
728 	mutex_lock(&info->port.mutex);
729 	if (tty_port_initialized(&info->port))
730  		wait_until_sent(tty, info->timeout);
731 	flush_buffer(tty);
732 	tty_ldisc_flush(tty);
733 
734 	shutdown(info);
735 	mutex_unlock(&info->port.mutex);
736 
737 	tty_port_close_end(&info->port, tty);
738 	info->port.tty = NULL;
739 cleanup:
740 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
741 }
742 
743 static void hangup(struct tty_struct *tty)
744 {
745 	struct slgt_info *info = tty->driver_data;
746 	unsigned long flags;
747 
748 	if (sanity_check(info, tty->name, "hangup"))
749 		return;
750 	DBGINFO(("%s hangup\n", info->device_name));
751 
752 	flush_buffer(tty);
753 
754 	mutex_lock(&info->port.mutex);
755 	shutdown(info);
756 
757 	spin_lock_irqsave(&info->port.lock, flags);
758 	info->port.count = 0;
759 	info->port.tty = NULL;
760 	spin_unlock_irqrestore(&info->port.lock, flags);
761 	tty_port_set_active(&info->port, 0);
762 	mutex_unlock(&info->port.mutex);
763 
764 	wake_up_interruptible(&info->port.open_wait);
765 }
766 
767 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
768 {
769 	struct slgt_info *info = tty->driver_data;
770 	unsigned long flags;
771 
772 	DBGINFO(("%s set_termios\n", tty->driver->name));
773 
774 	change_params(info);
775 
776 	/* Handle transition to B0 status */
777 	if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
778 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
779 		spin_lock_irqsave(&info->lock,flags);
780 		set_signals(info);
781 		spin_unlock_irqrestore(&info->lock,flags);
782 	}
783 
784 	/* Handle transition away from B0 status */
785 	if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
786 		info->signals |= SerialSignal_DTR;
787 		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
788 			info->signals |= SerialSignal_RTS;
789 		spin_lock_irqsave(&info->lock,flags);
790 	 	set_signals(info);
791 		spin_unlock_irqrestore(&info->lock,flags);
792 	}
793 
794 	/* Handle turning off CRTSCTS */
795 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
796 		tty->hw_stopped = 0;
797 		tx_release(tty);
798 	}
799 }
800 
801 static void update_tx_timer(struct slgt_info *info)
802 {
803 	/*
804 	 * use worst case speed of 1200bps to calculate transmit timeout
805 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
806 	 */
807 	if (info->params.mode == MGSL_MODE_HDLC) {
808 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
809 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
810 	}
811 }
812 
813 static int write(struct tty_struct *tty,
814 		 const unsigned char *buf, int count)
815 {
816 	int ret = 0;
817 	struct slgt_info *info = tty->driver_data;
818 	unsigned long flags;
819 
820 	if (sanity_check(info, tty->name, "write"))
821 		return -EIO;
822 
823 	DBGINFO(("%s write count=%d\n", info->device_name, count));
824 
825 	if (!info->tx_buf || (count > info->max_frame_size))
826 		return -EIO;
827 
828 	if (!count || tty->stopped || tty->hw_stopped)
829 		return 0;
830 
831 	spin_lock_irqsave(&info->lock, flags);
832 
833 	if (info->tx_count) {
834 		/* send accumulated data from send_char() */
835 		if (!tx_load(info, info->tx_buf, info->tx_count))
836 			goto cleanup;
837 		info->tx_count = 0;
838 	}
839 
840 	if (tx_load(info, buf, count))
841 		ret = count;
842 
843 cleanup:
844 	spin_unlock_irqrestore(&info->lock, flags);
845 	DBGINFO(("%s write rc=%d\n", info->device_name, ret));
846 	return ret;
847 }
848 
849 static int put_char(struct tty_struct *tty, unsigned char ch)
850 {
851 	struct slgt_info *info = tty->driver_data;
852 	unsigned long flags;
853 	int ret = 0;
854 
855 	if (sanity_check(info, tty->name, "put_char"))
856 		return 0;
857 	DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
858 	if (!info->tx_buf)
859 		return 0;
860 	spin_lock_irqsave(&info->lock,flags);
861 	if (info->tx_count < info->max_frame_size) {
862 		info->tx_buf[info->tx_count++] = ch;
863 		ret = 1;
864 	}
865 	spin_unlock_irqrestore(&info->lock,flags);
866 	return ret;
867 }
868 
869 static void send_xchar(struct tty_struct *tty, char ch)
870 {
871 	struct slgt_info *info = tty->driver_data;
872 	unsigned long flags;
873 
874 	if (sanity_check(info, tty->name, "send_xchar"))
875 		return;
876 	DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
877 	info->x_char = ch;
878 	if (ch) {
879 		spin_lock_irqsave(&info->lock,flags);
880 		if (!info->tx_enabled)
881 		 	tx_start(info);
882 		spin_unlock_irqrestore(&info->lock,flags);
883 	}
884 }
885 
886 static void wait_until_sent(struct tty_struct *tty, int timeout)
887 {
888 	struct slgt_info *info = tty->driver_data;
889 	unsigned long orig_jiffies, char_time;
890 
891 	if (!info )
892 		return;
893 	if (sanity_check(info, tty->name, "wait_until_sent"))
894 		return;
895 	DBGINFO(("%s wait_until_sent entry\n", info->device_name));
896 	if (!tty_port_initialized(&info->port))
897 		goto exit;
898 
899 	orig_jiffies = jiffies;
900 
901 	/* Set check interval to 1/5 of estimated time to
902 	 * send a character, and make it at least 1. The check
903 	 * interval should also be less than the timeout.
904 	 * Note: use tight timings here to satisfy the NIST-PCTS.
905 	 */
906 
907 	if (info->params.data_rate) {
908 	       	char_time = info->timeout/(32 * 5);
909 		if (!char_time)
910 			char_time++;
911 	} else
912 		char_time = 1;
913 
914 	if (timeout)
915 		char_time = min_t(unsigned long, char_time, timeout);
916 
917 	while (info->tx_active) {
918 		msleep_interruptible(jiffies_to_msecs(char_time));
919 		if (signal_pending(current))
920 			break;
921 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
922 			break;
923 	}
924 exit:
925 	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
926 }
927 
928 static int write_room(struct tty_struct *tty)
929 {
930 	struct slgt_info *info = tty->driver_data;
931 	int ret;
932 
933 	if (sanity_check(info, tty->name, "write_room"))
934 		return 0;
935 	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
936 	DBGINFO(("%s write_room=%d\n", info->device_name, ret));
937 	return ret;
938 }
939 
940 static void flush_chars(struct tty_struct *tty)
941 {
942 	struct slgt_info *info = tty->driver_data;
943 	unsigned long flags;
944 
945 	if (sanity_check(info, tty->name, "flush_chars"))
946 		return;
947 	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
948 
949 	if (info->tx_count <= 0 || tty->stopped ||
950 	    tty->hw_stopped || !info->tx_buf)
951 		return;
952 
953 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
954 
955 	spin_lock_irqsave(&info->lock,flags);
956 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
957 		info->tx_count = 0;
958 	spin_unlock_irqrestore(&info->lock,flags);
959 }
960 
961 static void flush_buffer(struct tty_struct *tty)
962 {
963 	struct slgt_info *info = tty->driver_data;
964 	unsigned long flags;
965 
966 	if (sanity_check(info, tty->name, "flush_buffer"))
967 		return;
968 	DBGINFO(("%s flush_buffer\n", info->device_name));
969 
970 	spin_lock_irqsave(&info->lock, flags);
971 	info->tx_count = 0;
972 	spin_unlock_irqrestore(&info->lock, flags);
973 
974 	tty_wakeup(tty);
975 }
976 
977 /*
978  * throttle (stop) transmitter
979  */
980 static void tx_hold(struct tty_struct *tty)
981 {
982 	struct slgt_info *info = tty->driver_data;
983 	unsigned long flags;
984 
985 	if (sanity_check(info, tty->name, "tx_hold"))
986 		return;
987 	DBGINFO(("%s tx_hold\n", info->device_name));
988 	spin_lock_irqsave(&info->lock,flags);
989 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
990 	 	tx_stop(info);
991 	spin_unlock_irqrestore(&info->lock,flags);
992 }
993 
994 /*
995  * release (start) transmitter
996  */
997 static void tx_release(struct tty_struct *tty)
998 {
999 	struct slgt_info *info = tty->driver_data;
1000 	unsigned long flags;
1001 
1002 	if (sanity_check(info, tty->name, "tx_release"))
1003 		return;
1004 	DBGINFO(("%s tx_release\n", info->device_name));
1005 	spin_lock_irqsave(&info->lock, flags);
1006 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
1007 		info->tx_count = 0;
1008 	spin_unlock_irqrestore(&info->lock, flags);
1009 }
1010 
1011 /*
1012  * Service an IOCTL request
1013  *
1014  * Arguments
1015  *
1016  * 	tty	pointer to tty instance data
1017  * 	cmd	IOCTL command code
1018  * 	arg	command argument/context
1019  *
1020  * Return 0 if success, otherwise error code
1021  */
1022 static int ioctl(struct tty_struct *tty,
1023 		 unsigned int cmd, unsigned long arg)
1024 {
1025 	struct slgt_info *info = tty->driver_data;
1026 	void __user *argp = (void __user *)arg;
1027 	int ret;
1028 
1029 	if (sanity_check(info, tty->name, "ioctl"))
1030 		return -ENODEV;
1031 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
1032 
1033 	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1034 	    (cmd != TIOCMIWAIT)) {
1035 		if (tty_io_error(tty))
1036 		    return -EIO;
1037 	}
1038 
1039 	switch (cmd) {
1040 	case MGSL_IOCWAITEVENT:
1041 		return wait_mgsl_event(info, argp);
1042 	case TIOCMIWAIT:
1043 		return modem_input_wait(info,(int)arg);
1044 	case MGSL_IOCSGPIO:
1045 		return set_gpio(info, argp);
1046 	case MGSL_IOCGGPIO:
1047 		return get_gpio(info, argp);
1048 	case MGSL_IOCWAITGPIO:
1049 		return wait_gpio(info, argp);
1050 	case MGSL_IOCGXSYNC:
1051 		return get_xsync(info, argp);
1052 	case MGSL_IOCSXSYNC:
1053 		return set_xsync(info, (int)arg);
1054 	case MGSL_IOCGXCTRL:
1055 		return get_xctrl(info, argp);
1056 	case MGSL_IOCSXCTRL:
1057 		return set_xctrl(info, (int)arg);
1058 	}
1059 	mutex_lock(&info->port.mutex);
1060 	switch (cmd) {
1061 	case MGSL_IOCGPARAMS:
1062 		ret = get_params(info, argp);
1063 		break;
1064 	case MGSL_IOCSPARAMS:
1065 		ret = set_params(info, argp);
1066 		break;
1067 	case MGSL_IOCGTXIDLE:
1068 		ret = get_txidle(info, argp);
1069 		break;
1070 	case MGSL_IOCSTXIDLE:
1071 		ret = set_txidle(info, (int)arg);
1072 		break;
1073 	case MGSL_IOCTXENABLE:
1074 		ret = tx_enable(info, (int)arg);
1075 		break;
1076 	case MGSL_IOCRXENABLE:
1077 		ret = rx_enable(info, (int)arg);
1078 		break;
1079 	case MGSL_IOCTXABORT:
1080 		ret = tx_abort(info);
1081 		break;
1082 	case MGSL_IOCGSTATS:
1083 		ret = get_stats(info, argp);
1084 		break;
1085 	case MGSL_IOCGIF:
1086 		ret = get_interface(info, argp);
1087 		break;
1088 	case MGSL_IOCSIF:
1089 		ret = set_interface(info,(int)arg);
1090 		break;
1091 	default:
1092 		ret = -ENOIOCTLCMD;
1093 	}
1094 	mutex_unlock(&info->port.mutex);
1095 	return ret;
1096 }
1097 
1098 static int get_icount(struct tty_struct *tty,
1099 				struct serial_icounter_struct *icount)
1100 
1101 {
1102 	struct slgt_info *info = tty->driver_data;
1103 	struct mgsl_icount cnow;	/* kernel counter temps */
1104 	unsigned long flags;
1105 
1106 	spin_lock_irqsave(&info->lock,flags);
1107 	cnow = info->icount;
1108 	spin_unlock_irqrestore(&info->lock,flags);
1109 
1110 	icount->cts = cnow.cts;
1111 	icount->dsr = cnow.dsr;
1112 	icount->rng = cnow.rng;
1113 	icount->dcd = cnow.dcd;
1114 	icount->rx = cnow.rx;
1115 	icount->tx = cnow.tx;
1116 	icount->frame = cnow.frame;
1117 	icount->overrun = cnow.overrun;
1118 	icount->parity = cnow.parity;
1119 	icount->brk = cnow.brk;
1120 	icount->buf_overrun = cnow.buf_overrun;
1121 
1122 	return 0;
1123 }
1124 
1125 /*
1126  * support for 32 bit ioctl calls on 64 bit systems
1127  */
1128 #ifdef CONFIG_COMPAT
1129 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1130 {
1131 	struct MGSL_PARAMS32 tmp_params;
1132 
1133 	DBGINFO(("%s get_params32\n", info->device_name));
1134 	memset(&tmp_params, 0, sizeof(tmp_params));
1135 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1136 	tmp_params.loopback        = info->params.loopback;
1137 	tmp_params.flags           = info->params.flags;
1138 	tmp_params.encoding        = info->params.encoding;
1139 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1140 	tmp_params.addr_filter     = info->params.addr_filter;
1141 	tmp_params.crc_type        = info->params.crc_type;
1142 	tmp_params.preamble_length = info->params.preamble_length;
1143 	tmp_params.preamble        = info->params.preamble;
1144 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1145 	tmp_params.data_bits       = info->params.data_bits;
1146 	tmp_params.stop_bits       = info->params.stop_bits;
1147 	tmp_params.parity          = info->params.parity;
1148 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1149 		return -EFAULT;
1150 	return 0;
1151 }
1152 
1153 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1154 {
1155 	struct MGSL_PARAMS32 tmp_params;
1156 
1157 	DBGINFO(("%s set_params32\n", info->device_name));
1158 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1159 		return -EFAULT;
1160 
1161 	spin_lock(&info->lock);
1162 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1163 		info->base_clock = tmp_params.clock_speed;
1164 	} else {
1165 		info->params.mode            = tmp_params.mode;
1166 		info->params.loopback        = tmp_params.loopback;
1167 		info->params.flags           = tmp_params.flags;
1168 		info->params.encoding        = tmp_params.encoding;
1169 		info->params.clock_speed     = tmp_params.clock_speed;
1170 		info->params.addr_filter     = tmp_params.addr_filter;
1171 		info->params.crc_type        = tmp_params.crc_type;
1172 		info->params.preamble_length = tmp_params.preamble_length;
1173 		info->params.preamble        = tmp_params.preamble;
1174 		info->params.data_rate       = tmp_params.data_rate;
1175 		info->params.data_bits       = tmp_params.data_bits;
1176 		info->params.stop_bits       = tmp_params.stop_bits;
1177 		info->params.parity          = tmp_params.parity;
1178 	}
1179 	spin_unlock(&info->lock);
1180 
1181 	program_hw(info);
1182 
1183 	return 0;
1184 }
1185 
1186 static long slgt_compat_ioctl(struct tty_struct *tty,
1187 			 unsigned int cmd, unsigned long arg)
1188 {
1189 	struct slgt_info *info = tty->driver_data;
1190 	int rc = -ENOIOCTLCMD;
1191 
1192 	if (sanity_check(info, tty->name, "compat_ioctl"))
1193 		return -ENODEV;
1194 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1195 
1196 	switch (cmd) {
1197 
1198 	case MGSL_IOCSPARAMS32:
1199 		rc = set_params32(info, compat_ptr(arg));
1200 		break;
1201 
1202 	case MGSL_IOCGPARAMS32:
1203 		rc = get_params32(info, compat_ptr(arg));
1204 		break;
1205 
1206 	case MGSL_IOCGPARAMS:
1207 	case MGSL_IOCSPARAMS:
1208 	case MGSL_IOCGTXIDLE:
1209 	case MGSL_IOCGSTATS:
1210 	case MGSL_IOCWAITEVENT:
1211 	case MGSL_IOCGIF:
1212 	case MGSL_IOCSGPIO:
1213 	case MGSL_IOCGGPIO:
1214 	case MGSL_IOCWAITGPIO:
1215 	case MGSL_IOCGXSYNC:
1216 	case MGSL_IOCGXCTRL:
1217 	case MGSL_IOCSTXIDLE:
1218 	case MGSL_IOCTXENABLE:
1219 	case MGSL_IOCRXENABLE:
1220 	case MGSL_IOCTXABORT:
1221 	case TIOCMIWAIT:
1222 	case MGSL_IOCSIF:
1223 	case MGSL_IOCSXSYNC:
1224 	case MGSL_IOCSXCTRL:
1225 		rc = ioctl(tty, cmd, arg);
1226 		break;
1227 	}
1228 
1229 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1230 	return rc;
1231 }
1232 #else
1233 #define slgt_compat_ioctl NULL
1234 #endif /* ifdef CONFIG_COMPAT */
1235 
1236 /*
1237  * proc fs support
1238  */
1239 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1240 {
1241 	char stat_buf[30];
1242 	unsigned long flags;
1243 
1244 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1245 		      info->device_name, info->phys_reg_addr,
1246 		      info->irq_level, info->max_frame_size);
1247 
1248 	/* output current serial signal states */
1249 	spin_lock_irqsave(&info->lock,flags);
1250 	get_signals(info);
1251 	spin_unlock_irqrestore(&info->lock,flags);
1252 
1253 	stat_buf[0] = 0;
1254 	stat_buf[1] = 0;
1255 	if (info->signals & SerialSignal_RTS)
1256 		strcat(stat_buf, "|RTS");
1257 	if (info->signals & SerialSignal_CTS)
1258 		strcat(stat_buf, "|CTS");
1259 	if (info->signals & SerialSignal_DTR)
1260 		strcat(stat_buf, "|DTR");
1261 	if (info->signals & SerialSignal_DSR)
1262 		strcat(stat_buf, "|DSR");
1263 	if (info->signals & SerialSignal_DCD)
1264 		strcat(stat_buf, "|CD");
1265 	if (info->signals & SerialSignal_RI)
1266 		strcat(stat_buf, "|RI");
1267 
1268 	if (info->params.mode != MGSL_MODE_ASYNC) {
1269 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1270 			       info->icount.txok, info->icount.rxok);
1271 		if (info->icount.txunder)
1272 			seq_printf(m, " txunder:%d", info->icount.txunder);
1273 		if (info->icount.txabort)
1274 			seq_printf(m, " txabort:%d", info->icount.txabort);
1275 		if (info->icount.rxshort)
1276 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1277 		if (info->icount.rxlong)
1278 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1279 		if (info->icount.rxover)
1280 			seq_printf(m, " rxover:%d", info->icount.rxover);
1281 		if (info->icount.rxcrc)
1282 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1283 	} else {
1284 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1285 			       info->icount.tx, info->icount.rx);
1286 		if (info->icount.frame)
1287 			seq_printf(m, " fe:%d", info->icount.frame);
1288 		if (info->icount.parity)
1289 			seq_printf(m, " pe:%d", info->icount.parity);
1290 		if (info->icount.brk)
1291 			seq_printf(m, " brk:%d", info->icount.brk);
1292 		if (info->icount.overrun)
1293 			seq_printf(m, " oe:%d", info->icount.overrun);
1294 	}
1295 
1296 	/* Append serial signal status to end */
1297 	seq_printf(m, " %s\n", stat_buf+1);
1298 
1299 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1300 		       info->tx_active,info->bh_requested,info->bh_running,
1301 		       info->pending_bh);
1302 }
1303 
1304 /* Called to print information about devices
1305  */
1306 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1307 {
1308 	struct slgt_info *info;
1309 
1310 	seq_puts(m, "synclink_gt driver\n");
1311 
1312 	info = slgt_device_list;
1313 	while( info ) {
1314 		line_info(m, info);
1315 		info = info->next_device;
1316 	}
1317 	return 0;
1318 }
1319 
1320 static int synclink_gt_proc_open(struct inode *inode, struct file *file)
1321 {
1322 	return single_open(file, synclink_gt_proc_show, NULL);
1323 }
1324 
1325 static const struct file_operations synclink_gt_proc_fops = {
1326 	.owner		= THIS_MODULE,
1327 	.open		= synclink_gt_proc_open,
1328 	.read		= seq_read,
1329 	.llseek		= seq_lseek,
1330 	.release	= single_release,
1331 };
1332 
1333 /*
1334  * return count of bytes in transmit buffer
1335  */
1336 static int chars_in_buffer(struct tty_struct *tty)
1337 {
1338 	struct slgt_info *info = tty->driver_data;
1339 	int count;
1340 	if (sanity_check(info, tty->name, "chars_in_buffer"))
1341 		return 0;
1342 	count = tbuf_bytes(info);
1343 	DBGINFO(("%s chars_in_buffer()=%d\n", info->device_name, count));
1344 	return count;
1345 }
1346 
1347 /*
1348  * signal remote device to throttle send data (our receive data)
1349  */
1350 static void throttle(struct tty_struct * tty)
1351 {
1352 	struct slgt_info *info = tty->driver_data;
1353 	unsigned long flags;
1354 
1355 	if (sanity_check(info, tty->name, "throttle"))
1356 		return;
1357 	DBGINFO(("%s throttle\n", info->device_name));
1358 	if (I_IXOFF(tty))
1359 		send_xchar(tty, STOP_CHAR(tty));
1360  	if (C_CRTSCTS(tty)) {
1361 		spin_lock_irqsave(&info->lock,flags);
1362 		info->signals &= ~SerialSignal_RTS;
1363 	 	set_signals(info);
1364 		spin_unlock_irqrestore(&info->lock,flags);
1365 	}
1366 }
1367 
1368 /*
1369  * signal remote device to stop throttling send data (our receive data)
1370  */
1371 static void unthrottle(struct tty_struct * tty)
1372 {
1373 	struct slgt_info *info = tty->driver_data;
1374 	unsigned long flags;
1375 
1376 	if (sanity_check(info, tty->name, "unthrottle"))
1377 		return;
1378 	DBGINFO(("%s unthrottle\n", info->device_name));
1379 	if (I_IXOFF(tty)) {
1380 		if (info->x_char)
1381 			info->x_char = 0;
1382 		else
1383 			send_xchar(tty, START_CHAR(tty));
1384 	}
1385  	if (C_CRTSCTS(tty)) {
1386 		spin_lock_irqsave(&info->lock,flags);
1387 		info->signals |= SerialSignal_RTS;
1388 	 	set_signals(info);
1389 		spin_unlock_irqrestore(&info->lock,flags);
1390 	}
1391 }
1392 
1393 /*
1394  * set or clear transmit break condition
1395  * break_state	-1=set break condition, 0=clear
1396  */
1397 static int set_break(struct tty_struct *tty, int break_state)
1398 {
1399 	struct slgt_info *info = tty->driver_data;
1400 	unsigned short value;
1401 	unsigned long flags;
1402 
1403 	if (sanity_check(info, tty->name, "set_break"))
1404 		return -EINVAL;
1405 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1406 
1407 	spin_lock_irqsave(&info->lock,flags);
1408 	value = rd_reg16(info, TCR);
1409  	if (break_state == -1)
1410 		value |= BIT6;
1411 	else
1412 		value &= ~BIT6;
1413 	wr_reg16(info, TCR, value);
1414 	spin_unlock_irqrestore(&info->lock,flags);
1415 	return 0;
1416 }
1417 
1418 #if SYNCLINK_GENERIC_HDLC
1419 
1420 /**
1421  * called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1422  * set encoding and frame check sequence (FCS) options
1423  *
1424  * dev       pointer to network device structure
1425  * encoding  serial encoding setting
1426  * parity    FCS setting
1427  *
1428  * returns 0 if success, otherwise error code
1429  */
1430 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1431 			  unsigned short parity)
1432 {
1433 	struct slgt_info *info = dev_to_port(dev);
1434 	unsigned char  new_encoding;
1435 	unsigned short new_crctype;
1436 
1437 	/* return error if TTY interface open */
1438 	if (info->port.count)
1439 		return -EBUSY;
1440 
1441 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1442 
1443 	switch (encoding)
1444 	{
1445 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1446 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1447 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1448 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1449 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1450 	default: return -EINVAL;
1451 	}
1452 
1453 	switch (parity)
1454 	{
1455 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1456 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1457 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1458 	default: return -EINVAL;
1459 	}
1460 
1461 	info->params.encoding = new_encoding;
1462 	info->params.crc_type = new_crctype;
1463 
1464 	/* if network interface up, reprogram hardware */
1465 	if (info->netcount)
1466 		program_hw(info);
1467 
1468 	return 0;
1469 }
1470 
1471 /**
1472  * called by generic HDLC layer to send frame
1473  *
1474  * skb  socket buffer containing HDLC frame
1475  * dev  pointer to network device structure
1476  */
1477 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1478 				      struct net_device *dev)
1479 {
1480 	struct slgt_info *info = dev_to_port(dev);
1481 	unsigned long flags;
1482 
1483 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1484 
1485 	if (!skb->len)
1486 		return NETDEV_TX_OK;
1487 
1488 	/* stop sending until this frame completes */
1489 	netif_stop_queue(dev);
1490 
1491 	/* update network statistics */
1492 	dev->stats.tx_packets++;
1493 	dev->stats.tx_bytes += skb->len;
1494 
1495 	/* save start time for transmit timeout detection */
1496 	netif_trans_update(dev);
1497 
1498 	spin_lock_irqsave(&info->lock, flags);
1499 	tx_load(info, skb->data, skb->len);
1500 	spin_unlock_irqrestore(&info->lock, flags);
1501 
1502 	/* done with socket buffer, so free it */
1503 	dev_kfree_skb(skb);
1504 
1505 	return NETDEV_TX_OK;
1506 }
1507 
1508 /**
1509  * called by network layer when interface enabled
1510  * claim resources and initialize hardware
1511  *
1512  * dev  pointer to network device structure
1513  *
1514  * returns 0 if success, otherwise error code
1515  */
1516 static int hdlcdev_open(struct net_device *dev)
1517 {
1518 	struct slgt_info *info = dev_to_port(dev);
1519 	int rc;
1520 	unsigned long flags;
1521 
1522 	if (!try_module_get(THIS_MODULE))
1523 		return -EBUSY;
1524 
1525 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1526 
1527 	/* generic HDLC layer open processing */
1528 	rc = hdlc_open(dev);
1529 	if (rc)
1530 		return rc;
1531 
1532 	/* arbitrate between network and tty opens */
1533 	spin_lock_irqsave(&info->netlock, flags);
1534 	if (info->port.count != 0 || info->netcount != 0) {
1535 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1536 		spin_unlock_irqrestore(&info->netlock, flags);
1537 		return -EBUSY;
1538 	}
1539 	info->netcount=1;
1540 	spin_unlock_irqrestore(&info->netlock, flags);
1541 
1542 	/* claim resources and init adapter */
1543 	if ((rc = startup(info)) != 0) {
1544 		spin_lock_irqsave(&info->netlock, flags);
1545 		info->netcount=0;
1546 		spin_unlock_irqrestore(&info->netlock, flags);
1547 		return rc;
1548 	}
1549 
1550 	/* assert RTS and DTR, apply hardware settings */
1551 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1552 	program_hw(info);
1553 
1554 	/* enable network layer transmit */
1555 	netif_trans_update(dev);
1556 	netif_start_queue(dev);
1557 
1558 	/* inform generic HDLC layer of current DCD status */
1559 	spin_lock_irqsave(&info->lock, flags);
1560 	get_signals(info);
1561 	spin_unlock_irqrestore(&info->lock, flags);
1562 	if (info->signals & SerialSignal_DCD)
1563 		netif_carrier_on(dev);
1564 	else
1565 		netif_carrier_off(dev);
1566 	return 0;
1567 }
1568 
1569 /**
1570  * called by network layer when interface is disabled
1571  * shutdown hardware and release resources
1572  *
1573  * dev  pointer to network device structure
1574  *
1575  * returns 0 if success, otherwise error code
1576  */
1577 static int hdlcdev_close(struct net_device *dev)
1578 {
1579 	struct slgt_info *info = dev_to_port(dev);
1580 	unsigned long flags;
1581 
1582 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1583 
1584 	netif_stop_queue(dev);
1585 
1586 	/* shutdown adapter and release resources */
1587 	shutdown(info);
1588 
1589 	hdlc_close(dev);
1590 
1591 	spin_lock_irqsave(&info->netlock, flags);
1592 	info->netcount=0;
1593 	spin_unlock_irqrestore(&info->netlock, flags);
1594 
1595 	module_put(THIS_MODULE);
1596 	return 0;
1597 }
1598 
1599 /**
1600  * called by network layer to process IOCTL call to network device
1601  *
1602  * dev  pointer to network device structure
1603  * ifr  pointer to network interface request structure
1604  * cmd  IOCTL command code
1605  *
1606  * returns 0 if success, otherwise error code
1607  */
1608 static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1609 {
1610 	const size_t size = sizeof(sync_serial_settings);
1611 	sync_serial_settings new_line;
1612 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1613 	struct slgt_info *info = dev_to_port(dev);
1614 	unsigned int flags;
1615 
1616 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1617 
1618 	/* return error if TTY interface open */
1619 	if (info->port.count)
1620 		return -EBUSY;
1621 
1622 	if (cmd != SIOCWANDEV)
1623 		return hdlc_ioctl(dev, ifr, cmd);
1624 
1625 	memset(&new_line, 0, sizeof(new_line));
1626 
1627 	switch(ifr->ifr_settings.type) {
1628 	case IF_GET_IFACE: /* return current sync_serial_settings */
1629 
1630 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
1631 		if (ifr->ifr_settings.size < size) {
1632 			ifr->ifr_settings.size = size; /* data size wanted */
1633 			return -ENOBUFS;
1634 		}
1635 
1636 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1637 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1638 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1639 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1640 
1641 		switch (flags){
1642 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1643 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1644 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1645 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1646 		default: new_line.clock_type = CLOCK_DEFAULT;
1647 		}
1648 
1649 		new_line.clock_rate = info->params.clock_speed;
1650 		new_line.loopback   = info->params.loopback ? 1:0;
1651 
1652 		if (copy_to_user(line, &new_line, size))
1653 			return -EFAULT;
1654 		return 0;
1655 
1656 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1657 
1658 		if(!capable(CAP_NET_ADMIN))
1659 			return -EPERM;
1660 		if (copy_from_user(&new_line, line, size))
1661 			return -EFAULT;
1662 
1663 		switch (new_line.clock_type)
1664 		{
1665 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1666 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1667 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1668 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1669 		case CLOCK_DEFAULT:  flags = info->params.flags &
1670 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1671 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1672 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1673 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1674 		default: return -EINVAL;
1675 		}
1676 
1677 		if (new_line.loopback != 0 && new_line.loopback != 1)
1678 			return -EINVAL;
1679 
1680 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1681 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1682 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1683 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1684 		info->params.flags |= flags;
1685 
1686 		info->params.loopback = new_line.loopback;
1687 
1688 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1689 			info->params.clock_speed = new_line.clock_rate;
1690 		else
1691 			info->params.clock_speed = 0;
1692 
1693 		/* if network interface up, reprogram hardware */
1694 		if (info->netcount)
1695 			program_hw(info);
1696 		return 0;
1697 
1698 	default:
1699 		return hdlc_ioctl(dev, ifr, cmd);
1700 	}
1701 }
1702 
1703 /**
1704  * called by network layer when transmit timeout is detected
1705  *
1706  * dev  pointer to network device structure
1707  */
1708 static void hdlcdev_tx_timeout(struct net_device *dev)
1709 {
1710 	struct slgt_info *info = dev_to_port(dev);
1711 	unsigned long flags;
1712 
1713 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1714 
1715 	dev->stats.tx_errors++;
1716 	dev->stats.tx_aborted_errors++;
1717 
1718 	spin_lock_irqsave(&info->lock,flags);
1719 	tx_stop(info);
1720 	spin_unlock_irqrestore(&info->lock,flags);
1721 
1722 	netif_wake_queue(dev);
1723 }
1724 
1725 /**
1726  * called by device driver when transmit completes
1727  * reenable network layer transmit if stopped
1728  *
1729  * info  pointer to device instance information
1730  */
1731 static void hdlcdev_tx_done(struct slgt_info *info)
1732 {
1733 	if (netif_queue_stopped(info->netdev))
1734 		netif_wake_queue(info->netdev);
1735 }
1736 
1737 /**
1738  * called by device driver when frame received
1739  * pass frame to network layer
1740  *
1741  * info  pointer to device instance information
1742  * buf   pointer to buffer contianing frame data
1743  * size  count of data bytes in buf
1744  */
1745 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1746 {
1747 	struct sk_buff *skb = dev_alloc_skb(size);
1748 	struct net_device *dev = info->netdev;
1749 
1750 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1751 
1752 	if (skb == NULL) {
1753 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1754 		dev->stats.rx_dropped++;
1755 		return;
1756 	}
1757 
1758 	memcpy(skb_put(skb, size), buf, size);
1759 
1760 	skb->protocol = hdlc_type_trans(skb, dev);
1761 
1762 	dev->stats.rx_packets++;
1763 	dev->stats.rx_bytes += size;
1764 
1765 	netif_rx(skb);
1766 }
1767 
1768 static const struct net_device_ops hdlcdev_ops = {
1769 	.ndo_open       = hdlcdev_open,
1770 	.ndo_stop       = hdlcdev_close,
1771 	.ndo_change_mtu = hdlc_change_mtu,
1772 	.ndo_start_xmit = hdlc_start_xmit,
1773 	.ndo_do_ioctl   = hdlcdev_ioctl,
1774 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1775 };
1776 
1777 /**
1778  * called by device driver when adding device instance
1779  * do generic HDLC initialization
1780  *
1781  * info  pointer to device instance information
1782  *
1783  * returns 0 if success, otherwise error code
1784  */
1785 static int hdlcdev_init(struct slgt_info *info)
1786 {
1787 	int rc;
1788 	struct net_device *dev;
1789 	hdlc_device *hdlc;
1790 
1791 	/* allocate and initialize network and HDLC layer objects */
1792 
1793 	dev = alloc_hdlcdev(info);
1794 	if (!dev) {
1795 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1796 		return -ENOMEM;
1797 	}
1798 
1799 	/* for network layer reporting purposes only */
1800 	dev->mem_start = info->phys_reg_addr;
1801 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1802 	dev->irq       = info->irq_level;
1803 
1804 	/* network layer callbacks and settings */
1805 	dev->netdev_ops	    = &hdlcdev_ops;
1806 	dev->watchdog_timeo = 10 * HZ;
1807 	dev->tx_queue_len   = 50;
1808 
1809 	/* generic HDLC layer callbacks and settings */
1810 	hdlc         = dev_to_hdlc(dev);
1811 	hdlc->attach = hdlcdev_attach;
1812 	hdlc->xmit   = hdlcdev_xmit;
1813 
1814 	/* register objects with HDLC layer */
1815 	rc = register_hdlc_device(dev);
1816 	if (rc) {
1817 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1818 		free_netdev(dev);
1819 		return rc;
1820 	}
1821 
1822 	info->netdev = dev;
1823 	return 0;
1824 }
1825 
1826 /**
1827  * called by device driver when removing device instance
1828  * do generic HDLC cleanup
1829  *
1830  * info  pointer to device instance information
1831  */
1832 static void hdlcdev_exit(struct slgt_info *info)
1833 {
1834 	unregister_hdlc_device(info->netdev);
1835 	free_netdev(info->netdev);
1836 	info->netdev = NULL;
1837 }
1838 
1839 #endif /* ifdef CONFIG_HDLC */
1840 
1841 /*
1842  * get async data from rx DMA buffers
1843  */
1844 static void rx_async(struct slgt_info *info)
1845 {
1846  	struct mgsl_icount *icount = &info->icount;
1847 	unsigned int start, end;
1848 	unsigned char *p;
1849 	unsigned char status;
1850 	struct slgt_desc *bufs = info->rbufs;
1851 	int i, count;
1852 	int chars = 0;
1853 	int stat;
1854 	unsigned char ch;
1855 
1856 	start = end = info->rbuf_current;
1857 
1858 	while(desc_complete(bufs[end])) {
1859 		count = desc_count(bufs[end]) - info->rbuf_index;
1860 		p     = bufs[end].buf + info->rbuf_index;
1861 
1862 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1863 		DBGDATA(info, p, count, "rx");
1864 
1865 		for(i=0 ; i < count; i+=2, p+=2) {
1866 			ch = *p;
1867 			icount->rx++;
1868 
1869 			stat = 0;
1870 
1871 			status = *(p + 1) & (BIT1 + BIT0);
1872 			if (status) {
1873 				if (status & BIT1)
1874 					icount->parity++;
1875 				else if (status & BIT0)
1876 					icount->frame++;
1877 				/* discard char if tty control flags say so */
1878 				if (status & info->ignore_status_mask)
1879 					continue;
1880 				if (status & BIT1)
1881 					stat = TTY_PARITY;
1882 				else if (status & BIT0)
1883 					stat = TTY_FRAME;
1884 			}
1885 			tty_insert_flip_char(&info->port, ch, stat);
1886 			chars++;
1887 		}
1888 
1889 		if (i < count) {
1890 			/* receive buffer not completed */
1891 			info->rbuf_index += i;
1892 			mod_timer(&info->rx_timer, jiffies + 1);
1893 			break;
1894 		}
1895 
1896 		info->rbuf_index = 0;
1897 		free_rbufs(info, end, end);
1898 
1899 		if (++end == info->rbuf_count)
1900 			end = 0;
1901 
1902 		/* if entire list searched then no frame available */
1903 		if (end == start)
1904 			break;
1905 	}
1906 
1907 	if (chars)
1908 		tty_flip_buffer_push(&info->port);
1909 }
1910 
1911 /*
1912  * return next bottom half action to perform
1913  */
1914 static int bh_action(struct slgt_info *info)
1915 {
1916 	unsigned long flags;
1917 	int rc;
1918 
1919 	spin_lock_irqsave(&info->lock,flags);
1920 
1921 	if (info->pending_bh & BH_RECEIVE) {
1922 		info->pending_bh &= ~BH_RECEIVE;
1923 		rc = BH_RECEIVE;
1924 	} else if (info->pending_bh & BH_TRANSMIT) {
1925 		info->pending_bh &= ~BH_TRANSMIT;
1926 		rc = BH_TRANSMIT;
1927 	} else if (info->pending_bh & BH_STATUS) {
1928 		info->pending_bh &= ~BH_STATUS;
1929 		rc = BH_STATUS;
1930 	} else {
1931 		/* Mark BH routine as complete */
1932 		info->bh_running = false;
1933 		info->bh_requested = false;
1934 		rc = 0;
1935 	}
1936 
1937 	spin_unlock_irqrestore(&info->lock,flags);
1938 
1939 	return rc;
1940 }
1941 
1942 /*
1943  * perform bottom half processing
1944  */
1945 static void bh_handler(struct work_struct *work)
1946 {
1947 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1948 	int action;
1949 
1950 	info->bh_running = true;
1951 
1952 	while((action = bh_action(info))) {
1953 		switch (action) {
1954 		case BH_RECEIVE:
1955 			DBGBH(("%s bh receive\n", info->device_name));
1956 			switch(info->params.mode) {
1957 			case MGSL_MODE_ASYNC:
1958 				rx_async(info);
1959 				break;
1960 			case MGSL_MODE_HDLC:
1961 				while(rx_get_frame(info));
1962 				break;
1963 			case MGSL_MODE_RAW:
1964 			case MGSL_MODE_MONOSYNC:
1965 			case MGSL_MODE_BISYNC:
1966 			case MGSL_MODE_XSYNC:
1967 				while(rx_get_buf(info));
1968 				break;
1969 			}
1970 			/* restart receiver if rx DMA buffers exhausted */
1971 			if (info->rx_restart)
1972 				rx_start(info);
1973 			break;
1974 		case BH_TRANSMIT:
1975 			bh_transmit(info);
1976 			break;
1977 		case BH_STATUS:
1978 			DBGBH(("%s bh status\n", info->device_name));
1979 			info->ri_chkcount = 0;
1980 			info->dsr_chkcount = 0;
1981 			info->dcd_chkcount = 0;
1982 			info->cts_chkcount = 0;
1983 			break;
1984 		default:
1985 			DBGBH(("%s unknown action\n", info->device_name));
1986 			break;
1987 		}
1988 	}
1989 	DBGBH(("%s bh_handler exit\n", info->device_name));
1990 }
1991 
1992 static void bh_transmit(struct slgt_info *info)
1993 {
1994 	struct tty_struct *tty = info->port.tty;
1995 
1996 	DBGBH(("%s bh_transmit\n", info->device_name));
1997 	if (tty)
1998 		tty_wakeup(tty);
1999 }
2000 
2001 static void dsr_change(struct slgt_info *info, unsigned short status)
2002 {
2003 	if (status & BIT3) {
2004 		info->signals |= SerialSignal_DSR;
2005 		info->input_signal_events.dsr_up++;
2006 	} else {
2007 		info->signals &= ~SerialSignal_DSR;
2008 		info->input_signal_events.dsr_down++;
2009 	}
2010 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
2011 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2012 		slgt_irq_off(info, IRQ_DSR);
2013 		return;
2014 	}
2015 	info->icount.dsr++;
2016 	wake_up_interruptible(&info->status_event_wait_q);
2017 	wake_up_interruptible(&info->event_wait_q);
2018 	info->pending_bh |= BH_STATUS;
2019 }
2020 
2021 static void cts_change(struct slgt_info *info, unsigned short status)
2022 {
2023 	if (status & BIT2) {
2024 		info->signals |= SerialSignal_CTS;
2025 		info->input_signal_events.cts_up++;
2026 	} else {
2027 		info->signals &= ~SerialSignal_CTS;
2028 		info->input_signal_events.cts_down++;
2029 	}
2030 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
2031 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2032 		slgt_irq_off(info, IRQ_CTS);
2033 		return;
2034 	}
2035 	info->icount.cts++;
2036 	wake_up_interruptible(&info->status_event_wait_q);
2037 	wake_up_interruptible(&info->event_wait_q);
2038 	info->pending_bh |= BH_STATUS;
2039 
2040 	if (tty_port_cts_enabled(&info->port)) {
2041 		if (info->port.tty) {
2042 			if (info->port.tty->hw_stopped) {
2043 				if (info->signals & SerialSignal_CTS) {
2044 		 			info->port.tty->hw_stopped = 0;
2045 					info->pending_bh |= BH_TRANSMIT;
2046 					return;
2047 				}
2048 			} else {
2049 				if (!(info->signals & SerialSignal_CTS))
2050 		 			info->port.tty->hw_stopped = 1;
2051 			}
2052 		}
2053 	}
2054 }
2055 
2056 static void dcd_change(struct slgt_info *info, unsigned short status)
2057 {
2058 	if (status & BIT1) {
2059 		info->signals |= SerialSignal_DCD;
2060 		info->input_signal_events.dcd_up++;
2061 	} else {
2062 		info->signals &= ~SerialSignal_DCD;
2063 		info->input_signal_events.dcd_down++;
2064 	}
2065 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
2066 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2067 		slgt_irq_off(info, IRQ_DCD);
2068 		return;
2069 	}
2070 	info->icount.dcd++;
2071 #if SYNCLINK_GENERIC_HDLC
2072 	if (info->netcount) {
2073 		if (info->signals & SerialSignal_DCD)
2074 			netif_carrier_on(info->netdev);
2075 		else
2076 			netif_carrier_off(info->netdev);
2077 	}
2078 #endif
2079 	wake_up_interruptible(&info->status_event_wait_q);
2080 	wake_up_interruptible(&info->event_wait_q);
2081 	info->pending_bh |= BH_STATUS;
2082 
2083 	if (tty_port_check_carrier(&info->port)) {
2084 		if (info->signals & SerialSignal_DCD)
2085 			wake_up_interruptible(&info->port.open_wait);
2086 		else {
2087 			if (info->port.tty)
2088 				tty_hangup(info->port.tty);
2089 		}
2090 	}
2091 }
2092 
2093 static void ri_change(struct slgt_info *info, unsigned short status)
2094 {
2095 	if (status & BIT0) {
2096 		info->signals |= SerialSignal_RI;
2097 		info->input_signal_events.ri_up++;
2098 	} else {
2099 		info->signals &= ~SerialSignal_RI;
2100 		info->input_signal_events.ri_down++;
2101 	}
2102 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2103 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2104 		slgt_irq_off(info, IRQ_RI);
2105 		return;
2106 	}
2107 	info->icount.rng++;
2108 	wake_up_interruptible(&info->status_event_wait_q);
2109 	wake_up_interruptible(&info->event_wait_q);
2110 	info->pending_bh |= BH_STATUS;
2111 }
2112 
2113 static void isr_rxdata(struct slgt_info *info)
2114 {
2115 	unsigned int count = info->rbuf_fill_count;
2116 	unsigned int i = info->rbuf_fill_index;
2117 	unsigned short reg;
2118 
2119 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2120 		reg = rd_reg16(info, RDR);
2121 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2122 		if (desc_complete(info->rbufs[i])) {
2123 			/* all buffers full */
2124 			rx_stop(info);
2125 			info->rx_restart = 1;
2126 			continue;
2127 		}
2128 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2129 		/* async mode saves status byte to buffer for each data byte */
2130 		if (info->params.mode == MGSL_MODE_ASYNC)
2131 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2132 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2133 			/* buffer full or end of frame */
2134 			set_desc_count(info->rbufs[i], count);
2135 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2136 			info->rbuf_fill_count = count = 0;
2137 			if (++i == info->rbuf_count)
2138 				i = 0;
2139 			info->pending_bh |= BH_RECEIVE;
2140 		}
2141 	}
2142 
2143 	info->rbuf_fill_index = i;
2144 	info->rbuf_fill_count = count;
2145 }
2146 
2147 static void isr_serial(struct slgt_info *info)
2148 {
2149 	unsigned short status = rd_reg16(info, SSR);
2150 
2151 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2152 
2153 	wr_reg16(info, SSR, status); /* clear pending */
2154 
2155 	info->irq_occurred = true;
2156 
2157 	if (info->params.mode == MGSL_MODE_ASYNC) {
2158 		if (status & IRQ_TXIDLE) {
2159 			if (info->tx_active)
2160 				isr_txeom(info, status);
2161 		}
2162 		if (info->rx_pio && (status & IRQ_RXDATA))
2163 			isr_rxdata(info);
2164 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2165 			info->icount.brk++;
2166 			/* process break detection if tty control allows */
2167 			if (info->port.tty) {
2168 				if (!(status & info->ignore_status_mask)) {
2169 					if (info->read_status_mask & MASK_BREAK) {
2170 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2171 						if (info->port.flags & ASYNC_SAK)
2172 							do_SAK(info->port.tty);
2173 					}
2174 				}
2175 			}
2176 		}
2177 	} else {
2178 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2179 			isr_txeom(info, status);
2180 		if (info->rx_pio && (status & IRQ_RXDATA))
2181 			isr_rxdata(info);
2182 		if (status & IRQ_RXIDLE) {
2183 			if (status & RXIDLE)
2184 				info->icount.rxidle++;
2185 			else
2186 				info->icount.exithunt++;
2187 			wake_up_interruptible(&info->event_wait_q);
2188 		}
2189 
2190 		if (status & IRQ_RXOVER)
2191 			rx_start(info);
2192 	}
2193 
2194 	if (status & IRQ_DSR)
2195 		dsr_change(info, status);
2196 	if (status & IRQ_CTS)
2197 		cts_change(info, status);
2198 	if (status & IRQ_DCD)
2199 		dcd_change(info, status);
2200 	if (status & IRQ_RI)
2201 		ri_change(info, status);
2202 }
2203 
2204 static void isr_rdma(struct slgt_info *info)
2205 {
2206 	unsigned int status = rd_reg32(info, RDCSR);
2207 
2208 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2209 
2210 	/* RDCSR (rx DMA control/status)
2211 	 *
2212 	 * 31..07  reserved
2213 	 * 06      save status byte to DMA buffer
2214 	 * 05      error
2215 	 * 04      eol (end of list)
2216 	 * 03      eob (end of buffer)
2217 	 * 02      IRQ enable
2218 	 * 01      reset
2219 	 * 00      enable
2220 	 */
2221 	wr_reg32(info, RDCSR, status);	/* clear pending */
2222 
2223 	if (status & (BIT5 + BIT4)) {
2224 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2225 		info->rx_restart = true;
2226 	}
2227 	info->pending_bh |= BH_RECEIVE;
2228 }
2229 
2230 static void isr_tdma(struct slgt_info *info)
2231 {
2232 	unsigned int status = rd_reg32(info, TDCSR);
2233 
2234 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2235 
2236 	/* TDCSR (tx DMA control/status)
2237 	 *
2238 	 * 31..06  reserved
2239 	 * 05      error
2240 	 * 04      eol (end of list)
2241 	 * 03      eob (end of buffer)
2242 	 * 02      IRQ enable
2243 	 * 01      reset
2244 	 * 00      enable
2245 	 */
2246 	wr_reg32(info, TDCSR, status);	/* clear pending */
2247 
2248 	if (status & (BIT5 + BIT4 + BIT3)) {
2249 		// another transmit buffer has completed
2250 		// run bottom half to get more send data from user
2251 		info->pending_bh |= BH_TRANSMIT;
2252 	}
2253 }
2254 
2255 /*
2256  * return true if there are unsent tx DMA buffers, otherwise false
2257  *
2258  * if there are unsent buffers then info->tbuf_start
2259  * is set to index of first unsent buffer
2260  */
2261 static bool unsent_tbufs(struct slgt_info *info)
2262 {
2263 	unsigned int i = info->tbuf_current;
2264 	bool rc = false;
2265 
2266 	/*
2267 	 * search backwards from last loaded buffer (precedes tbuf_current)
2268 	 * for first unsent buffer (desc_count > 0)
2269 	 */
2270 
2271 	do {
2272 		if (i)
2273 			i--;
2274 		else
2275 			i = info->tbuf_count - 1;
2276 		if (!desc_count(info->tbufs[i]))
2277 			break;
2278 		info->tbuf_start = i;
2279 		rc = true;
2280 	} while (i != info->tbuf_current);
2281 
2282 	return rc;
2283 }
2284 
2285 static void isr_txeom(struct slgt_info *info, unsigned short status)
2286 {
2287 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2288 
2289 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2290 	tdma_reset(info);
2291 	if (status & IRQ_TXUNDER) {
2292 		unsigned short val = rd_reg16(info, TCR);
2293 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2294 		wr_reg16(info, TCR, val); /* clear reset bit */
2295 	}
2296 
2297 	if (info->tx_active) {
2298 		if (info->params.mode != MGSL_MODE_ASYNC) {
2299 			if (status & IRQ_TXUNDER)
2300 				info->icount.txunder++;
2301 			else if (status & IRQ_TXIDLE)
2302 				info->icount.txok++;
2303 		}
2304 
2305 		if (unsent_tbufs(info)) {
2306 			tx_start(info);
2307 			update_tx_timer(info);
2308 			return;
2309 		}
2310 		info->tx_active = false;
2311 
2312 		del_timer(&info->tx_timer);
2313 
2314 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2315 			info->signals &= ~SerialSignal_RTS;
2316 			info->drop_rts_on_tx_done = false;
2317 			set_signals(info);
2318 		}
2319 
2320 #if SYNCLINK_GENERIC_HDLC
2321 		if (info->netcount)
2322 			hdlcdev_tx_done(info);
2323 		else
2324 #endif
2325 		{
2326 			if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
2327 				tx_stop(info);
2328 				return;
2329 			}
2330 			info->pending_bh |= BH_TRANSMIT;
2331 		}
2332 	}
2333 }
2334 
2335 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2336 {
2337 	struct cond_wait *w, *prev;
2338 
2339 	/* wake processes waiting for specific transitions */
2340 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2341 		if (w->data & changed) {
2342 			w->data = state;
2343 			wake_up_interruptible(&w->q);
2344 			if (prev != NULL)
2345 				prev->next = w->next;
2346 			else
2347 				info->gpio_wait_q = w->next;
2348 		} else
2349 			prev = w;
2350 	}
2351 }
2352 
2353 /* interrupt service routine
2354  *
2355  * 	irq	interrupt number
2356  * 	dev_id	device ID supplied during interrupt registration
2357  */
2358 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2359 {
2360 	struct slgt_info *info = dev_id;
2361 	unsigned int gsr;
2362 	unsigned int i;
2363 
2364 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2365 
2366 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2367 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2368 		info->irq_occurred = true;
2369 		for(i=0; i < info->port_count ; i++) {
2370 			if (info->port_array[i] == NULL)
2371 				continue;
2372 			spin_lock(&info->port_array[i]->lock);
2373 			if (gsr & (BIT8 << i))
2374 				isr_serial(info->port_array[i]);
2375 			if (gsr & (BIT16 << (i*2)))
2376 				isr_rdma(info->port_array[i]);
2377 			if (gsr & (BIT17 << (i*2)))
2378 				isr_tdma(info->port_array[i]);
2379 			spin_unlock(&info->port_array[i]->lock);
2380 		}
2381 	}
2382 
2383 	if (info->gpio_present) {
2384 		unsigned int state;
2385 		unsigned int changed;
2386 		spin_lock(&info->lock);
2387 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2388 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2389 			/* read latched state of GPIO signals */
2390 			state = rd_reg32(info, IOVR);
2391 			/* clear pending GPIO interrupt bits */
2392 			wr_reg32(info, IOSR, changed);
2393 			for (i=0 ; i < info->port_count ; i++) {
2394 				if (info->port_array[i] != NULL)
2395 					isr_gpio(info->port_array[i], changed, state);
2396 			}
2397 		}
2398 		spin_unlock(&info->lock);
2399 	}
2400 
2401 	for(i=0; i < info->port_count ; i++) {
2402 		struct slgt_info *port = info->port_array[i];
2403 		if (port == NULL)
2404 			continue;
2405 		spin_lock(&port->lock);
2406 		if ((port->port.count || port->netcount) &&
2407 		    port->pending_bh && !port->bh_running &&
2408 		    !port->bh_requested) {
2409 			DBGISR(("%s bh queued\n", port->device_name));
2410 			schedule_work(&port->task);
2411 			port->bh_requested = true;
2412 		}
2413 		spin_unlock(&port->lock);
2414 	}
2415 
2416 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2417 	return IRQ_HANDLED;
2418 }
2419 
2420 static int startup(struct slgt_info *info)
2421 {
2422 	DBGINFO(("%s startup\n", info->device_name));
2423 
2424 	if (tty_port_initialized(&info->port))
2425 		return 0;
2426 
2427 	if (!info->tx_buf) {
2428 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2429 		if (!info->tx_buf) {
2430 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2431 			return -ENOMEM;
2432 		}
2433 	}
2434 
2435 	info->pending_bh = 0;
2436 
2437 	memset(&info->icount, 0, sizeof(info->icount));
2438 
2439 	/* program hardware for current parameters */
2440 	change_params(info);
2441 
2442 	if (info->port.tty)
2443 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2444 
2445 	tty_port_set_initialized(&info->port, 1);
2446 
2447 	return 0;
2448 }
2449 
2450 /*
2451  *  called by close() and hangup() to shutdown hardware
2452  */
2453 static void shutdown(struct slgt_info *info)
2454 {
2455 	unsigned long flags;
2456 
2457 	if (!tty_port_initialized(&info->port))
2458 		return;
2459 
2460 	DBGINFO(("%s shutdown\n", info->device_name));
2461 
2462 	/* clear status wait queue because status changes */
2463 	/* can't happen after shutting down the hardware */
2464 	wake_up_interruptible(&info->status_event_wait_q);
2465 	wake_up_interruptible(&info->event_wait_q);
2466 
2467 	del_timer_sync(&info->tx_timer);
2468 	del_timer_sync(&info->rx_timer);
2469 
2470 	kfree(info->tx_buf);
2471 	info->tx_buf = NULL;
2472 
2473 	spin_lock_irqsave(&info->lock,flags);
2474 
2475 	tx_stop(info);
2476 	rx_stop(info);
2477 
2478 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2479 
2480  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2481 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2482 		set_signals(info);
2483 	}
2484 
2485 	flush_cond_wait(&info->gpio_wait_q);
2486 
2487 	spin_unlock_irqrestore(&info->lock,flags);
2488 
2489 	if (info->port.tty)
2490 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2491 
2492 	tty_port_set_initialized(&info->port, 0);
2493 }
2494 
2495 static void program_hw(struct slgt_info *info)
2496 {
2497 	unsigned long flags;
2498 
2499 	spin_lock_irqsave(&info->lock,flags);
2500 
2501 	rx_stop(info);
2502 	tx_stop(info);
2503 
2504 	if (info->params.mode != MGSL_MODE_ASYNC ||
2505 	    info->netcount)
2506 		sync_mode(info);
2507 	else
2508 		async_mode(info);
2509 
2510 	set_signals(info);
2511 
2512 	info->dcd_chkcount = 0;
2513 	info->cts_chkcount = 0;
2514 	info->ri_chkcount = 0;
2515 	info->dsr_chkcount = 0;
2516 
2517 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2518 	get_signals(info);
2519 
2520 	if (info->netcount ||
2521 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2522 		rx_start(info);
2523 
2524 	spin_unlock_irqrestore(&info->lock,flags);
2525 }
2526 
2527 /*
2528  * reconfigure adapter based on new parameters
2529  */
2530 static void change_params(struct slgt_info *info)
2531 {
2532 	unsigned cflag;
2533 	int bits_per_char;
2534 
2535 	if (!info->port.tty)
2536 		return;
2537 	DBGINFO(("%s change_params\n", info->device_name));
2538 
2539 	cflag = info->port.tty->termios.c_cflag;
2540 
2541 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2542 	/* otherwise assert RTS and DTR */
2543  	if (cflag & CBAUD)
2544 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2545 	else
2546 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2547 
2548 	/* byte size and parity */
2549 
2550 	switch (cflag & CSIZE) {
2551 	case CS5: info->params.data_bits = 5; break;
2552 	case CS6: info->params.data_bits = 6; break;
2553 	case CS7: info->params.data_bits = 7; break;
2554 	case CS8: info->params.data_bits = 8; break;
2555 	default:  info->params.data_bits = 7; break;
2556 	}
2557 
2558 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2559 
2560 	if (cflag & PARENB)
2561 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2562 	else
2563 		info->params.parity = ASYNC_PARITY_NONE;
2564 
2565 	/* calculate number of jiffies to transmit a full
2566 	 * FIFO (32 bytes) at specified data rate
2567 	 */
2568 	bits_per_char = info->params.data_bits +
2569 			info->params.stop_bits + 1;
2570 
2571 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2572 
2573 	if (info->params.data_rate) {
2574 		info->timeout = (32*HZ*bits_per_char) /
2575 				info->params.data_rate;
2576 	}
2577 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2578 
2579 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2580 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2581 
2582 	/* process tty input control flags */
2583 
2584 	info->read_status_mask = IRQ_RXOVER;
2585 	if (I_INPCK(info->port.tty))
2586 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2587  	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2588  		info->read_status_mask |= MASK_BREAK;
2589 	if (I_IGNPAR(info->port.tty))
2590 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2591 	if (I_IGNBRK(info->port.tty)) {
2592 		info->ignore_status_mask |= MASK_BREAK;
2593 		/* If ignoring parity and break indicators, ignore
2594 		 * overruns too.  (For real raw support).
2595 		 */
2596 		if (I_IGNPAR(info->port.tty))
2597 			info->ignore_status_mask |= MASK_OVERRUN;
2598 	}
2599 
2600 	program_hw(info);
2601 }
2602 
2603 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2604 {
2605 	DBGINFO(("%s get_stats\n",  info->device_name));
2606 	if (!user_icount) {
2607 		memset(&info->icount, 0, sizeof(info->icount));
2608 	} else {
2609 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2610 			return -EFAULT;
2611 	}
2612 	return 0;
2613 }
2614 
2615 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2616 {
2617 	DBGINFO(("%s get_params\n", info->device_name));
2618 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2619 		return -EFAULT;
2620 	return 0;
2621 }
2622 
2623 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2624 {
2625  	unsigned long flags;
2626 	MGSL_PARAMS tmp_params;
2627 
2628 	DBGINFO(("%s set_params\n", info->device_name));
2629 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2630 		return -EFAULT;
2631 
2632 	spin_lock_irqsave(&info->lock, flags);
2633 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2634 		info->base_clock = tmp_params.clock_speed;
2635 	else
2636 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2637 	spin_unlock_irqrestore(&info->lock, flags);
2638 
2639 	program_hw(info);
2640 
2641 	return 0;
2642 }
2643 
2644 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2645 {
2646 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2647 	if (put_user(info->idle_mode, idle_mode))
2648 		return -EFAULT;
2649 	return 0;
2650 }
2651 
2652 static int set_txidle(struct slgt_info *info, int idle_mode)
2653 {
2654  	unsigned long flags;
2655 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2656 	spin_lock_irqsave(&info->lock,flags);
2657 	info->idle_mode = idle_mode;
2658 	if (info->params.mode != MGSL_MODE_ASYNC)
2659 		tx_set_idle(info);
2660 	spin_unlock_irqrestore(&info->lock,flags);
2661 	return 0;
2662 }
2663 
2664 static int tx_enable(struct slgt_info *info, int enable)
2665 {
2666  	unsigned long flags;
2667 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2668 	spin_lock_irqsave(&info->lock,flags);
2669 	if (enable) {
2670 		if (!info->tx_enabled)
2671 			tx_start(info);
2672 	} else {
2673 		if (info->tx_enabled)
2674 			tx_stop(info);
2675 	}
2676 	spin_unlock_irqrestore(&info->lock,flags);
2677 	return 0;
2678 }
2679 
2680 /*
2681  * abort transmit HDLC frame
2682  */
2683 static int tx_abort(struct slgt_info *info)
2684 {
2685  	unsigned long flags;
2686 	DBGINFO(("%s tx_abort\n", info->device_name));
2687 	spin_lock_irqsave(&info->lock,flags);
2688 	tdma_reset(info);
2689 	spin_unlock_irqrestore(&info->lock,flags);
2690 	return 0;
2691 }
2692 
2693 static int rx_enable(struct slgt_info *info, int enable)
2694 {
2695  	unsigned long flags;
2696 	unsigned int rbuf_fill_level;
2697 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2698 	spin_lock_irqsave(&info->lock,flags);
2699 	/*
2700 	 * enable[31..16] = receive DMA buffer fill level
2701 	 * 0 = noop (leave fill level unchanged)
2702 	 * fill level must be multiple of 4 and <= buffer size
2703 	 */
2704 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2705 	if (rbuf_fill_level) {
2706 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2707 			spin_unlock_irqrestore(&info->lock, flags);
2708 			return -EINVAL;
2709 		}
2710 		info->rbuf_fill_level = rbuf_fill_level;
2711 		if (rbuf_fill_level < 128)
2712 			info->rx_pio = 1; /* PIO mode */
2713 		else
2714 			info->rx_pio = 0; /* DMA mode */
2715 		rx_stop(info); /* restart receiver to use new fill level */
2716 	}
2717 
2718 	/*
2719 	 * enable[1..0] = receiver enable command
2720 	 * 0 = disable
2721 	 * 1 = enable
2722 	 * 2 = enable or force hunt mode if already enabled
2723 	 */
2724 	enable &= 3;
2725 	if (enable) {
2726 		if (!info->rx_enabled)
2727 			rx_start(info);
2728 		else if (enable == 2) {
2729 			/* force hunt mode (write 1 to RCR[3]) */
2730 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2731 		}
2732 	} else {
2733 		if (info->rx_enabled)
2734 			rx_stop(info);
2735 	}
2736 	spin_unlock_irqrestore(&info->lock,flags);
2737 	return 0;
2738 }
2739 
2740 /*
2741  *  wait for specified event to occur
2742  */
2743 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2744 {
2745  	unsigned long flags;
2746 	int s;
2747 	int rc=0;
2748 	struct mgsl_icount cprev, cnow;
2749 	int events;
2750 	int mask;
2751 	struct	_input_signal_events oldsigs, newsigs;
2752 	DECLARE_WAITQUEUE(wait, current);
2753 
2754 	if (get_user(mask, mask_ptr))
2755 		return -EFAULT;
2756 
2757 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2758 
2759 	spin_lock_irqsave(&info->lock,flags);
2760 
2761 	/* return immediately if state matches requested events */
2762 	get_signals(info);
2763 	s = info->signals;
2764 
2765 	events = mask &
2766 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2767  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2768 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2769 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2770 	if (events) {
2771 		spin_unlock_irqrestore(&info->lock,flags);
2772 		goto exit;
2773 	}
2774 
2775 	/* save current irq counts */
2776 	cprev = info->icount;
2777 	oldsigs = info->input_signal_events;
2778 
2779 	/* enable hunt and idle irqs if needed */
2780 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2781 		unsigned short val = rd_reg16(info, SCR);
2782 		if (!(val & IRQ_RXIDLE))
2783 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2784 	}
2785 
2786 	set_current_state(TASK_INTERRUPTIBLE);
2787 	add_wait_queue(&info->event_wait_q, &wait);
2788 
2789 	spin_unlock_irqrestore(&info->lock,flags);
2790 
2791 	for(;;) {
2792 		schedule();
2793 		if (signal_pending(current)) {
2794 			rc = -ERESTARTSYS;
2795 			break;
2796 		}
2797 
2798 		/* get current irq counts */
2799 		spin_lock_irqsave(&info->lock,flags);
2800 		cnow = info->icount;
2801 		newsigs = info->input_signal_events;
2802 		set_current_state(TASK_INTERRUPTIBLE);
2803 		spin_unlock_irqrestore(&info->lock,flags);
2804 
2805 		/* if no change, wait aborted for some reason */
2806 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2807 		    newsigs.dsr_down == oldsigs.dsr_down &&
2808 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2809 		    newsigs.dcd_down == oldsigs.dcd_down &&
2810 		    newsigs.cts_up   == oldsigs.cts_up   &&
2811 		    newsigs.cts_down == oldsigs.cts_down &&
2812 		    newsigs.ri_up    == oldsigs.ri_up    &&
2813 		    newsigs.ri_down  == oldsigs.ri_down  &&
2814 		    cnow.exithunt    == cprev.exithunt   &&
2815 		    cnow.rxidle      == cprev.rxidle) {
2816 			rc = -EIO;
2817 			break;
2818 		}
2819 
2820 		events = mask &
2821 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2822 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2823 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2824 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2825 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2826 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2827 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2828 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2829 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2830 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2831 		if (events)
2832 			break;
2833 
2834 		cprev = cnow;
2835 		oldsigs = newsigs;
2836 	}
2837 
2838 	remove_wait_queue(&info->event_wait_q, &wait);
2839 	set_current_state(TASK_RUNNING);
2840 
2841 
2842 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2843 		spin_lock_irqsave(&info->lock,flags);
2844 		if (!waitqueue_active(&info->event_wait_q)) {
2845 			/* disable enable exit hunt mode/idle rcvd IRQs */
2846 			wr_reg16(info, SCR,
2847 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2848 		}
2849 		spin_unlock_irqrestore(&info->lock,flags);
2850 	}
2851 exit:
2852 	if (rc == 0)
2853 		rc = put_user(events, mask_ptr);
2854 	return rc;
2855 }
2856 
2857 static int get_interface(struct slgt_info *info, int __user *if_mode)
2858 {
2859 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2860 	if (put_user(info->if_mode, if_mode))
2861 		return -EFAULT;
2862 	return 0;
2863 }
2864 
2865 static int set_interface(struct slgt_info *info, int if_mode)
2866 {
2867  	unsigned long flags;
2868 	unsigned short val;
2869 
2870 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2871 	spin_lock_irqsave(&info->lock,flags);
2872 	info->if_mode = if_mode;
2873 
2874 	msc_set_vcr(info);
2875 
2876 	/* TCR (tx control) 07  1=RTS driver control */
2877 	val = rd_reg16(info, TCR);
2878 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2879 		val |= BIT7;
2880 	else
2881 		val &= ~BIT7;
2882 	wr_reg16(info, TCR, val);
2883 
2884 	spin_unlock_irqrestore(&info->lock,flags);
2885 	return 0;
2886 }
2887 
2888 static int get_xsync(struct slgt_info *info, int __user *xsync)
2889 {
2890 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2891 	if (put_user(info->xsync, xsync))
2892 		return -EFAULT;
2893 	return 0;
2894 }
2895 
2896 /*
2897  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2898  *
2899  * sync pattern is contained in least significant bytes of value
2900  * most significant byte of sync pattern is oldest (1st sent/detected)
2901  */
2902 static int set_xsync(struct slgt_info *info, int xsync)
2903 {
2904 	unsigned long flags;
2905 
2906 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2907 	spin_lock_irqsave(&info->lock, flags);
2908 	info->xsync = xsync;
2909 	wr_reg32(info, XSR, xsync);
2910 	spin_unlock_irqrestore(&info->lock, flags);
2911 	return 0;
2912 }
2913 
2914 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2915 {
2916 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2917 	if (put_user(info->xctrl, xctrl))
2918 		return -EFAULT;
2919 	return 0;
2920 }
2921 
2922 /*
2923  * set extended control options
2924  *
2925  * xctrl[31:19] reserved, must be zero
2926  * xctrl[18:17] extended sync pattern length in bytes
2927  *              00 = 1 byte  in xsr[7:0]
2928  *              01 = 2 bytes in xsr[15:0]
2929  *              10 = 3 bytes in xsr[23:0]
2930  *              11 = 4 bytes in xsr[31:0]
2931  * xctrl[16]    1 = enable terminal count, 0=disabled
2932  * xctrl[15:0]  receive terminal count for fixed length packets
2933  *              value is count minus one (0 = 1 byte packet)
2934  *              when terminal count is reached, receiver
2935  *              automatically returns to hunt mode and receive
2936  *              FIFO contents are flushed to DMA buffers with
2937  *              end of frame (EOF) status
2938  */
2939 static int set_xctrl(struct slgt_info *info, int xctrl)
2940 {
2941 	unsigned long flags;
2942 
2943 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2944 	spin_lock_irqsave(&info->lock, flags);
2945 	info->xctrl = xctrl;
2946 	wr_reg32(info, XCR, xctrl);
2947 	spin_unlock_irqrestore(&info->lock, flags);
2948 	return 0;
2949 }
2950 
2951 /*
2952  * set general purpose IO pin state and direction
2953  *
2954  * user_gpio fields:
2955  * state   each bit indicates a pin state
2956  * smask   set bit indicates pin state to set
2957  * dir     each bit indicates a pin direction (0=input, 1=output)
2958  * dmask   set bit indicates pin direction to set
2959  */
2960 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2961 {
2962  	unsigned long flags;
2963 	struct gpio_desc gpio;
2964 	__u32 data;
2965 
2966 	if (!info->gpio_present)
2967 		return -EINVAL;
2968 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2969 		return -EFAULT;
2970 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2971 		 info->device_name, gpio.state, gpio.smask,
2972 		 gpio.dir, gpio.dmask));
2973 
2974 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2975 	if (gpio.dmask) {
2976 		data = rd_reg32(info, IODR);
2977 		data |= gpio.dmask & gpio.dir;
2978 		data &= ~(gpio.dmask & ~gpio.dir);
2979 		wr_reg32(info, IODR, data);
2980 	}
2981 	if (gpio.smask) {
2982 		data = rd_reg32(info, IOVR);
2983 		data |= gpio.smask & gpio.state;
2984 		data &= ~(gpio.smask & ~gpio.state);
2985 		wr_reg32(info, IOVR, data);
2986 	}
2987 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2988 
2989 	return 0;
2990 }
2991 
2992 /*
2993  * get general purpose IO pin state and direction
2994  */
2995 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2996 {
2997 	struct gpio_desc gpio;
2998 	if (!info->gpio_present)
2999 		return -EINVAL;
3000 	gpio.state = rd_reg32(info, IOVR);
3001 	gpio.smask = 0xffffffff;
3002 	gpio.dir   = rd_reg32(info, IODR);
3003 	gpio.dmask = 0xffffffff;
3004 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3005 		return -EFAULT;
3006 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
3007 		 info->device_name, gpio.state, gpio.dir));
3008 	return 0;
3009 }
3010 
3011 /*
3012  * conditional wait facility
3013  */
3014 static void init_cond_wait(struct cond_wait *w, unsigned int data)
3015 {
3016 	init_waitqueue_head(&w->q);
3017 	init_waitqueue_entry(&w->wait, current);
3018 	w->data = data;
3019 }
3020 
3021 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
3022 {
3023 	set_current_state(TASK_INTERRUPTIBLE);
3024 	add_wait_queue(&w->q, &w->wait);
3025 	w->next = *head;
3026 	*head = w;
3027 }
3028 
3029 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
3030 {
3031 	struct cond_wait *w, *prev;
3032 	remove_wait_queue(&cw->q, &cw->wait);
3033 	set_current_state(TASK_RUNNING);
3034 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
3035 		if (w == cw) {
3036 			if (prev != NULL)
3037 				prev->next = w->next;
3038 			else
3039 				*head = w->next;
3040 			break;
3041 		}
3042 	}
3043 }
3044 
3045 static void flush_cond_wait(struct cond_wait **head)
3046 {
3047 	while (*head != NULL) {
3048 		wake_up_interruptible(&(*head)->q);
3049 		*head = (*head)->next;
3050 	}
3051 }
3052 
3053 /*
3054  * wait for general purpose I/O pin(s) to enter specified state
3055  *
3056  * user_gpio fields:
3057  * state - bit indicates target pin state
3058  * smask - set bit indicates watched pin
3059  *
3060  * The wait ends when at least one watched pin enters the specified
3061  * state. When 0 (no error) is returned, user_gpio->state is set to the
3062  * state of all GPIO pins when the wait ends.
3063  *
3064  * Note: Each pin may be a dedicated input, dedicated output, or
3065  * configurable input/output. The number and configuration of pins
3066  * varies with the specific adapter model. Only input pins (dedicated
3067  * or configured) can be monitored with this function.
3068  */
3069 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3070 {
3071  	unsigned long flags;
3072 	int rc = 0;
3073 	struct gpio_desc gpio;
3074 	struct cond_wait wait;
3075 	u32 state;
3076 
3077 	if (!info->gpio_present)
3078 		return -EINVAL;
3079 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
3080 		return -EFAULT;
3081 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3082 		 info->device_name, gpio.state, gpio.smask));
3083 	/* ignore output pins identified by set IODR bit */
3084 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3085 		return -EINVAL;
3086 	init_cond_wait(&wait, gpio.smask);
3087 
3088 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3089 	/* enable interrupts for watched pins */
3090 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3091 	/* get current pin states */
3092 	state = rd_reg32(info, IOVR);
3093 
3094 	if (gpio.smask & ~(state ^ gpio.state)) {
3095 		/* already in target state */
3096 		gpio.state = state;
3097 	} else {
3098 		/* wait for target state */
3099 		add_cond_wait(&info->gpio_wait_q, &wait);
3100 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3101 		schedule();
3102 		if (signal_pending(current))
3103 			rc = -ERESTARTSYS;
3104 		else
3105 			gpio.state = wait.data;
3106 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3107 		remove_cond_wait(&info->gpio_wait_q, &wait);
3108 	}
3109 
3110 	/* disable all GPIO interrupts if no waiting processes */
3111 	if (info->gpio_wait_q == NULL)
3112 		wr_reg32(info, IOER, 0);
3113 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3114 
3115 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3116 		rc = -EFAULT;
3117 	return rc;
3118 }
3119 
3120 static int modem_input_wait(struct slgt_info *info,int arg)
3121 {
3122  	unsigned long flags;
3123 	int rc;
3124 	struct mgsl_icount cprev, cnow;
3125 	DECLARE_WAITQUEUE(wait, current);
3126 
3127 	/* save current irq counts */
3128 	spin_lock_irqsave(&info->lock,flags);
3129 	cprev = info->icount;
3130 	add_wait_queue(&info->status_event_wait_q, &wait);
3131 	set_current_state(TASK_INTERRUPTIBLE);
3132 	spin_unlock_irqrestore(&info->lock,flags);
3133 
3134 	for(;;) {
3135 		schedule();
3136 		if (signal_pending(current)) {
3137 			rc = -ERESTARTSYS;
3138 			break;
3139 		}
3140 
3141 		/* get new irq counts */
3142 		spin_lock_irqsave(&info->lock,flags);
3143 		cnow = info->icount;
3144 		set_current_state(TASK_INTERRUPTIBLE);
3145 		spin_unlock_irqrestore(&info->lock,flags);
3146 
3147 		/* if no change, wait aborted for some reason */
3148 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3149 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3150 			rc = -EIO;
3151 			break;
3152 		}
3153 
3154 		/* check for change in caller specified modem input */
3155 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3156 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3157 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3158 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3159 			rc = 0;
3160 			break;
3161 		}
3162 
3163 		cprev = cnow;
3164 	}
3165 	remove_wait_queue(&info->status_event_wait_q, &wait);
3166 	set_current_state(TASK_RUNNING);
3167 	return rc;
3168 }
3169 
3170 /*
3171  *  return state of serial control and status signals
3172  */
3173 static int tiocmget(struct tty_struct *tty)
3174 {
3175 	struct slgt_info *info = tty->driver_data;
3176 	unsigned int result;
3177  	unsigned long flags;
3178 
3179 	spin_lock_irqsave(&info->lock,flags);
3180  	get_signals(info);
3181 	spin_unlock_irqrestore(&info->lock,flags);
3182 
3183 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3184 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3185 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3186 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3187 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3188 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3189 
3190 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3191 	return result;
3192 }
3193 
3194 /*
3195  * set modem control signals (DTR/RTS)
3196  *
3197  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3198  *		TIOCMSET = set/clear signal values
3199  * 	value	bit mask for command
3200  */
3201 static int tiocmset(struct tty_struct *tty,
3202 		    unsigned int set, unsigned int clear)
3203 {
3204 	struct slgt_info *info = tty->driver_data;
3205  	unsigned long flags;
3206 
3207 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3208 
3209 	if (set & TIOCM_RTS)
3210 		info->signals |= SerialSignal_RTS;
3211 	if (set & TIOCM_DTR)
3212 		info->signals |= SerialSignal_DTR;
3213 	if (clear & TIOCM_RTS)
3214 		info->signals &= ~SerialSignal_RTS;
3215 	if (clear & TIOCM_DTR)
3216 		info->signals &= ~SerialSignal_DTR;
3217 
3218 	spin_lock_irqsave(&info->lock,flags);
3219  	set_signals(info);
3220 	spin_unlock_irqrestore(&info->lock,flags);
3221 	return 0;
3222 }
3223 
3224 static int carrier_raised(struct tty_port *port)
3225 {
3226 	unsigned long flags;
3227 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3228 
3229 	spin_lock_irqsave(&info->lock,flags);
3230  	get_signals(info);
3231 	spin_unlock_irqrestore(&info->lock,flags);
3232 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3233 }
3234 
3235 static void dtr_rts(struct tty_port *port, int on)
3236 {
3237 	unsigned long flags;
3238 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3239 
3240 	spin_lock_irqsave(&info->lock,flags);
3241 	if (on)
3242 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3243 	else
3244 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3245  	set_signals(info);
3246 	spin_unlock_irqrestore(&info->lock,flags);
3247 }
3248 
3249 
3250 /*
3251  *  block current process until the device is ready to open
3252  */
3253 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3254 			   struct slgt_info *info)
3255 {
3256 	DECLARE_WAITQUEUE(wait, current);
3257 	int		retval;
3258 	bool		do_clocal = false;
3259 	unsigned long	flags;
3260 	int		cd;
3261 	struct tty_port *port = &info->port;
3262 
3263 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3264 
3265 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3266 		/* nonblock mode is set or port is not enabled */
3267 		tty_port_set_active(port, 1);
3268 		return 0;
3269 	}
3270 
3271 	if (C_CLOCAL(tty))
3272 		do_clocal = true;
3273 
3274 	/* Wait for carrier detect and the line to become
3275 	 * free (i.e., not in use by the callout).  While we are in
3276 	 * this loop, port->count is dropped by one, so that
3277 	 * close() knows when to free things.  We restore it upon
3278 	 * exit, either normal or abnormal.
3279 	 */
3280 
3281 	retval = 0;
3282 	add_wait_queue(&port->open_wait, &wait);
3283 
3284 	spin_lock_irqsave(&info->lock, flags);
3285 	port->count--;
3286 	spin_unlock_irqrestore(&info->lock, flags);
3287 	port->blocked_open++;
3288 
3289 	while (1) {
3290 		if (C_BAUD(tty) && tty_port_initialized(port))
3291 			tty_port_raise_dtr_rts(port);
3292 
3293 		set_current_state(TASK_INTERRUPTIBLE);
3294 
3295 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3296 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3297 					-EAGAIN : -ERESTARTSYS;
3298 			break;
3299 		}
3300 
3301 		cd = tty_port_carrier_raised(port);
3302 		if (do_clocal || cd)
3303 			break;
3304 
3305 		if (signal_pending(current)) {
3306 			retval = -ERESTARTSYS;
3307 			break;
3308 		}
3309 
3310 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3311 		tty_unlock(tty);
3312 		schedule();
3313 		tty_lock(tty);
3314 	}
3315 
3316 	set_current_state(TASK_RUNNING);
3317 	remove_wait_queue(&port->open_wait, &wait);
3318 
3319 	if (!tty_hung_up_p(filp))
3320 		port->count++;
3321 	port->blocked_open--;
3322 
3323 	if (!retval)
3324 		tty_port_set_active(port, 1);
3325 
3326 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3327 	return retval;
3328 }
3329 
3330 /*
3331  * allocate buffers used for calling line discipline receive_buf
3332  * directly in synchronous mode
3333  * note: add 5 bytes to max frame size to allow appending
3334  * 32-bit CRC and status byte when configured to do so
3335  */
3336 static int alloc_tmp_rbuf(struct slgt_info *info)
3337 {
3338 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3339 	if (info->tmp_rbuf == NULL)
3340 		return -ENOMEM;
3341 	/* unused flag buffer to satisfy receive_buf calling interface */
3342 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3343 	if (!info->flag_buf) {
3344 		kfree(info->tmp_rbuf);
3345 		info->tmp_rbuf = NULL;
3346 		return -ENOMEM;
3347 	}
3348 	return 0;
3349 }
3350 
3351 static void free_tmp_rbuf(struct slgt_info *info)
3352 {
3353 	kfree(info->tmp_rbuf);
3354 	info->tmp_rbuf = NULL;
3355 	kfree(info->flag_buf);
3356 	info->flag_buf = NULL;
3357 }
3358 
3359 /*
3360  * allocate DMA descriptor lists.
3361  */
3362 static int alloc_desc(struct slgt_info *info)
3363 {
3364 	unsigned int i;
3365 	unsigned int pbufs;
3366 
3367 	/* allocate memory to hold descriptor lists */
3368 	info->bufs = pci_zalloc_consistent(info->pdev, DESC_LIST_SIZE,
3369 					   &info->bufs_dma_addr);
3370 	if (info->bufs == NULL)
3371 		return -ENOMEM;
3372 
3373 	info->rbufs = (struct slgt_desc*)info->bufs;
3374 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3375 
3376 	pbufs = (unsigned int)info->bufs_dma_addr;
3377 
3378 	/*
3379 	 * Build circular lists of descriptors
3380 	 */
3381 
3382 	for (i=0; i < info->rbuf_count; i++) {
3383 		/* physical address of this descriptor */
3384 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3385 
3386 		/* physical address of next descriptor */
3387 		if (i == info->rbuf_count - 1)
3388 			info->rbufs[i].next = cpu_to_le32(pbufs);
3389 		else
3390 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3391 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3392 	}
3393 
3394 	for (i=0; i < info->tbuf_count; i++) {
3395 		/* physical address of this descriptor */
3396 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3397 
3398 		/* physical address of next descriptor */
3399 		if (i == info->tbuf_count - 1)
3400 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3401 		else
3402 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3403 	}
3404 
3405 	return 0;
3406 }
3407 
3408 static void free_desc(struct slgt_info *info)
3409 {
3410 	if (info->bufs != NULL) {
3411 		pci_free_consistent(info->pdev, DESC_LIST_SIZE, info->bufs, info->bufs_dma_addr);
3412 		info->bufs  = NULL;
3413 		info->rbufs = NULL;
3414 		info->tbufs = NULL;
3415 	}
3416 }
3417 
3418 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3419 {
3420 	int i;
3421 	for (i=0; i < count; i++) {
3422 		if ((bufs[i].buf = pci_alloc_consistent(info->pdev, DMABUFSIZE, &bufs[i].buf_dma_addr)) == NULL)
3423 			return -ENOMEM;
3424 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3425 	}
3426 	return 0;
3427 }
3428 
3429 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3430 {
3431 	int i;
3432 	for (i=0; i < count; i++) {
3433 		if (bufs[i].buf == NULL)
3434 			continue;
3435 		pci_free_consistent(info->pdev, DMABUFSIZE, bufs[i].buf, bufs[i].buf_dma_addr);
3436 		bufs[i].buf = NULL;
3437 	}
3438 }
3439 
3440 static int alloc_dma_bufs(struct slgt_info *info)
3441 {
3442 	info->rbuf_count = 32;
3443 	info->tbuf_count = 32;
3444 
3445 	if (alloc_desc(info) < 0 ||
3446 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3447 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3448 	    alloc_tmp_rbuf(info) < 0) {
3449 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3450 		return -ENOMEM;
3451 	}
3452 	reset_rbufs(info);
3453 	return 0;
3454 }
3455 
3456 static void free_dma_bufs(struct slgt_info *info)
3457 {
3458 	if (info->bufs) {
3459 		free_bufs(info, info->rbufs, info->rbuf_count);
3460 		free_bufs(info, info->tbufs, info->tbuf_count);
3461 		free_desc(info);
3462 	}
3463 	free_tmp_rbuf(info);
3464 }
3465 
3466 static int claim_resources(struct slgt_info *info)
3467 {
3468 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3469 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3470 			info->device_name, info->phys_reg_addr));
3471 		info->init_error = DiagStatus_AddressConflict;
3472 		goto errout;
3473 	}
3474 	else
3475 		info->reg_addr_requested = true;
3476 
3477 	info->reg_addr = ioremap_nocache(info->phys_reg_addr, SLGT_REG_SIZE);
3478 	if (!info->reg_addr) {
3479 		DBGERR(("%s can't map device registers, addr=%08X\n",
3480 			info->device_name, info->phys_reg_addr));
3481 		info->init_error = DiagStatus_CantAssignPciResources;
3482 		goto errout;
3483 	}
3484 	return 0;
3485 
3486 errout:
3487 	release_resources(info);
3488 	return -ENODEV;
3489 }
3490 
3491 static void release_resources(struct slgt_info *info)
3492 {
3493 	if (info->irq_requested) {
3494 		free_irq(info->irq_level, info);
3495 		info->irq_requested = false;
3496 	}
3497 
3498 	if (info->reg_addr_requested) {
3499 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3500 		info->reg_addr_requested = false;
3501 	}
3502 
3503 	if (info->reg_addr) {
3504 		iounmap(info->reg_addr);
3505 		info->reg_addr = NULL;
3506 	}
3507 }
3508 
3509 /* Add the specified device instance data structure to the
3510  * global linked list of devices and increment the device count.
3511  */
3512 static void add_device(struct slgt_info *info)
3513 {
3514 	char *devstr;
3515 
3516 	info->next_device = NULL;
3517 	info->line = slgt_device_count;
3518 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3519 
3520 	if (info->line < MAX_DEVICES) {
3521 		if (maxframe[info->line])
3522 			info->max_frame_size = maxframe[info->line];
3523 	}
3524 
3525 	slgt_device_count++;
3526 
3527 	if (!slgt_device_list)
3528 		slgt_device_list = info;
3529 	else {
3530 		struct slgt_info *current_dev = slgt_device_list;
3531 		while(current_dev->next_device)
3532 			current_dev = current_dev->next_device;
3533 		current_dev->next_device = info;
3534 	}
3535 
3536 	if (info->max_frame_size < 4096)
3537 		info->max_frame_size = 4096;
3538 	else if (info->max_frame_size > 65535)
3539 		info->max_frame_size = 65535;
3540 
3541 	switch(info->pdev->device) {
3542 	case SYNCLINK_GT_DEVICE_ID:
3543 		devstr = "GT";
3544 		break;
3545 	case SYNCLINK_GT2_DEVICE_ID:
3546 		devstr = "GT2";
3547 		break;
3548 	case SYNCLINK_GT4_DEVICE_ID:
3549 		devstr = "GT4";
3550 		break;
3551 	case SYNCLINK_AC_DEVICE_ID:
3552 		devstr = "AC";
3553 		info->params.mode = MGSL_MODE_ASYNC;
3554 		break;
3555 	default:
3556 		devstr = "(unknown model)";
3557 	}
3558 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3559 		devstr, info->device_name, info->phys_reg_addr,
3560 		info->irq_level, info->max_frame_size);
3561 
3562 #if SYNCLINK_GENERIC_HDLC
3563 	hdlcdev_init(info);
3564 #endif
3565 }
3566 
3567 static const struct tty_port_operations slgt_port_ops = {
3568 	.carrier_raised = carrier_raised,
3569 	.dtr_rts = dtr_rts,
3570 };
3571 
3572 /*
3573  *  allocate device instance structure, return NULL on failure
3574  */
3575 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3576 {
3577 	struct slgt_info *info;
3578 
3579 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3580 
3581 	if (!info) {
3582 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3583 			driver_name, adapter_num, port_num));
3584 	} else {
3585 		tty_port_init(&info->port);
3586 		info->port.ops = &slgt_port_ops;
3587 		info->magic = MGSL_MAGIC;
3588 		INIT_WORK(&info->task, bh_handler);
3589 		info->max_frame_size = 4096;
3590 		info->base_clock = 14745600;
3591 		info->rbuf_fill_level = DMABUFSIZE;
3592 		info->port.close_delay = 5*HZ/10;
3593 		info->port.closing_wait = 30*HZ;
3594 		init_waitqueue_head(&info->status_event_wait_q);
3595 		init_waitqueue_head(&info->event_wait_q);
3596 		spin_lock_init(&info->netlock);
3597 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3598 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3599 		info->adapter_num = adapter_num;
3600 		info->port_num = port_num;
3601 
3602 		setup_timer(&info->tx_timer, tx_timeout, (unsigned long)info);
3603 		setup_timer(&info->rx_timer, rx_timeout, (unsigned long)info);
3604 
3605 		/* Copy configuration info to device instance data */
3606 		info->pdev = pdev;
3607 		info->irq_level = pdev->irq;
3608 		info->phys_reg_addr = pci_resource_start(pdev,0);
3609 
3610 		info->bus_type = MGSL_BUS_TYPE_PCI;
3611 		info->irq_flags = IRQF_SHARED;
3612 
3613 		info->init_error = -1; /* assume error, set to 0 on successful init */
3614 	}
3615 
3616 	return info;
3617 }
3618 
3619 static void device_init(int adapter_num, struct pci_dev *pdev)
3620 {
3621 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3622 	int i;
3623 	int port_count = 1;
3624 
3625 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3626 		port_count = 2;
3627 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3628 		port_count = 4;
3629 
3630 	/* allocate device instances for all ports */
3631 	for (i=0; i < port_count; ++i) {
3632 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3633 		if (port_array[i] == NULL) {
3634 			for (--i; i >= 0; --i) {
3635 				tty_port_destroy(&port_array[i]->port);
3636 				kfree(port_array[i]);
3637 			}
3638 			return;
3639 		}
3640 	}
3641 
3642 	/* give copy of port_array to all ports and add to device list  */
3643 	for (i=0; i < port_count; ++i) {
3644 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3645 		add_device(port_array[i]);
3646 		port_array[i]->port_count = port_count;
3647 		spin_lock_init(&port_array[i]->lock);
3648 	}
3649 
3650 	/* Allocate and claim adapter resources */
3651 	if (!claim_resources(port_array[0])) {
3652 
3653 		alloc_dma_bufs(port_array[0]);
3654 
3655 		/* copy resource information from first port to others */
3656 		for (i = 1; i < port_count; ++i) {
3657 			port_array[i]->irq_level = port_array[0]->irq_level;
3658 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3659 			alloc_dma_bufs(port_array[i]);
3660 		}
3661 
3662 		if (request_irq(port_array[0]->irq_level,
3663 					slgt_interrupt,
3664 					port_array[0]->irq_flags,
3665 					port_array[0]->device_name,
3666 					port_array[0]) < 0) {
3667 			DBGERR(("%s request_irq failed IRQ=%d\n",
3668 				port_array[0]->device_name,
3669 				port_array[0]->irq_level));
3670 		} else {
3671 			port_array[0]->irq_requested = true;
3672 			adapter_test(port_array[0]);
3673 			for (i=1 ; i < port_count ; i++) {
3674 				port_array[i]->init_error = port_array[0]->init_error;
3675 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3676 			}
3677 		}
3678 	}
3679 
3680 	for (i = 0; i < port_count; ++i) {
3681 		struct slgt_info *info = port_array[i];
3682 		tty_port_register_device(&info->port, serial_driver, info->line,
3683 				&info->pdev->dev);
3684 	}
3685 }
3686 
3687 static int init_one(struct pci_dev *dev,
3688 			      const struct pci_device_id *ent)
3689 {
3690 	if (pci_enable_device(dev)) {
3691 		printk("error enabling pci device %p\n", dev);
3692 		return -EIO;
3693 	}
3694 	pci_set_master(dev);
3695 	device_init(slgt_device_count, dev);
3696 	return 0;
3697 }
3698 
3699 static void remove_one(struct pci_dev *dev)
3700 {
3701 }
3702 
3703 static const struct tty_operations ops = {
3704 	.open = open,
3705 	.close = close,
3706 	.write = write,
3707 	.put_char = put_char,
3708 	.flush_chars = flush_chars,
3709 	.write_room = write_room,
3710 	.chars_in_buffer = chars_in_buffer,
3711 	.flush_buffer = flush_buffer,
3712 	.ioctl = ioctl,
3713 	.compat_ioctl = slgt_compat_ioctl,
3714 	.throttle = throttle,
3715 	.unthrottle = unthrottle,
3716 	.send_xchar = send_xchar,
3717 	.break_ctl = set_break,
3718 	.wait_until_sent = wait_until_sent,
3719 	.set_termios = set_termios,
3720 	.stop = tx_hold,
3721 	.start = tx_release,
3722 	.hangup = hangup,
3723 	.tiocmget = tiocmget,
3724 	.tiocmset = tiocmset,
3725 	.get_icount = get_icount,
3726 	.proc_fops = &synclink_gt_proc_fops,
3727 };
3728 
3729 static void slgt_cleanup(void)
3730 {
3731 	int rc;
3732 	struct slgt_info *info;
3733 	struct slgt_info *tmp;
3734 
3735 	printk(KERN_INFO "unload %s\n", driver_name);
3736 
3737 	if (serial_driver) {
3738 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3739 			tty_unregister_device(serial_driver, info->line);
3740 		rc = tty_unregister_driver(serial_driver);
3741 		if (rc)
3742 			DBGERR(("tty_unregister_driver error=%d\n", rc));
3743 		put_tty_driver(serial_driver);
3744 	}
3745 
3746 	/* reset devices */
3747 	info = slgt_device_list;
3748 	while(info) {
3749 		reset_port(info);
3750 		info = info->next_device;
3751 	}
3752 
3753 	/* release devices */
3754 	info = slgt_device_list;
3755 	while(info) {
3756 #if SYNCLINK_GENERIC_HDLC
3757 		hdlcdev_exit(info);
3758 #endif
3759 		free_dma_bufs(info);
3760 		free_tmp_rbuf(info);
3761 		if (info->port_num == 0)
3762 			release_resources(info);
3763 		tmp = info;
3764 		info = info->next_device;
3765 		tty_port_destroy(&tmp->port);
3766 		kfree(tmp);
3767 	}
3768 
3769 	if (pci_registered)
3770 		pci_unregister_driver(&pci_driver);
3771 }
3772 
3773 /*
3774  *  Driver initialization entry point.
3775  */
3776 static int __init slgt_init(void)
3777 {
3778 	int rc;
3779 
3780 	printk(KERN_INFO "%s\n", driver_name);
3781 
3782 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3783 	if (!serial_driver) {
3784 		printk("%s can't allocate tty driver\n", driver_name);
3785 		return -ENOMEM;
3786 	}
3787 
3788 	/* Initialize the tty_driver structure */
3789 
3790 	serial_driver->driver_name = slgt_driver_name;
3791 	serial_driver->name = tty_dev_prefix;
3792 	serial_driver->major = ttymajor;
3793 	serial_driver->minor_start = 64;
3794 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3795 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3796 	serial_driver->init_termios = tty_std_termios;
3797 	serial_driver->init_termios.c_cflag =
3798 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3799 	serial_driver->init_termios.c_ispeed = 9600;
3800 	serial_driver->init_termios.c_ospeed = 9600;
3801 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3802 	tty_set_operations(serial_driver, &ops);
3803 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3804 		DBGERR(("%s can't register serial driver\n", driver_name));
3805 		put_tty_driver(serial_driver);
3806 		serial_driver = NULL;
3807 		goto error;
3808 	}
3809 
3810 	printk(KERN_INFO "%s, tty major#%d\n",
3811 	       driver_name, serial_driver->major);
3812 
3813 	slgt_device_count = 0;
3814 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3815 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3816 		goto error;
3817 	}
3818 	pci_registered = true;
3819 
3820 	if (!slgt_device_list)
3821 		printk("%s no devices found\n",driver_name);
3822 
3823 	return 0;
3824 
3825 error:
3826 	slgt_cleanup();
3827 	return rc;
3828 }
3829 
3830 static void __exit slgt_exit(void)
3831 {
3832 	slgt_cleanup();
3833 }
3834 
3835 module_init(slgt_init);
3836 module_exit(slgt_exit);
3837 
3838 /*
3839  * register access routines
3840  */
3841 
3842 #define CALC_REGADDR() \
3843 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3844 	if (addr >= 0x80) \
3845 		reg_addr += (info->port_num) * 32; \
3846 	else if (addr >= 0x40)	\
3847 		reg_addr += (info->port_num) * 16;
3848 
3849 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3850 {
3851 	CALC_REGADDR();
3852 	return readb((void __iomem *)reg_addr);
3853 }
3854 
3855 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3856 {
3857 	CALC_REGADDR();
3858 	writeb(value, (void __iomem *)reg_addr);
3859 }
3860 
3861 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3862 {
3863 	CALC_REGADDR();
3864 	return readw((void __iomem *)reg_addr);
3865 }
3866 
3867 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3868 {
3869 	CALC_REGADDR();
3870 	writew(value, (void __iomem *)reg_addr);
3871 }
3872 
3873 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3874 {
3875 	CALC_REGADDR();
3876 	return readl((void __iomem *)reg_addr);
3877 }
3878 
3879 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3880 {
3881 	CALC_REGADDR();
3882 	writel(value, (void __iomem *)reg_addr);
3883 }
3884 
3885 static void rdma_reset(struct slgt_info *info)
3886 {
3887 	unsigned int i;
3888 
3889 	/* set reset bit */
3890 	wr_reg32(info, RDCSR, BIT1);
3891 
3892 	/* wait for enable bit cleared */
3893 	for(i=0 ; i < 1000 ; i++)
3894 		if (!(rd_reg32(info, RDCSR) & BIT0))
3895 			break;
3896 }
3897 
3898 static void tdma_reset(struct slgt_info *info)
3899 {
3900 	unsigned int i;
3901 
3902 	/* set reset bit */
3903 	wr_reg32(info, TDCSR, BIT1);
3904 
3905 	/* wait for enable bit cleared */
3906 	for(i=0 ; i < 1000 ; i++)
3907 		if (!(rd_reg32(info, TDCSR) & BIT0))
3908 			break;
3909 }
3910 
3911 /*
3912  * enable internal loopback
3913  * TxCLK and RxCLK are generated from BRG
3914  * and TxD is looped back to RxD internally.
3915  */
3916 static void enable_loopback(struct slgt_info *info)
3917 {
3918 	/* SCR (serial control) BIT2=loopback enable */
3919 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3920 
3921 	if (info->params.mode != MGSL_MODE_ASYNC) {
3922 		/* CCR (clock control)
3923 		 * 07..05  tx clock source (010 = BRG)
3924 		 * 04..02  rx clock source (010 = BRG)
3925 		 * 01      auxclk enable   (0 = disable)
3926 		 * 00      BRG enable      (1 = enable)
3927 		 *
3928 		 * 0100 1001
3929 		 */
3930 		wr_reg8(info, CCR, 0x49);
3931 
3932 		/* set speed if available, otherwise use default */
3933 		if (info->params.clock_speed)
3934 			set_rate(info, info->params.clock_speed);
3935 		else
3936 			set_rate(info, 3686400);
3937 	}
3938 }
3939 
3940 /*
3941  *  set baud rate generator to specified rate
3942  */
3943 static void set_rate(struct slgt_info *info, u32 rate)
3944 {
3945 	unsigned int div;
3946 	unsigned int osc = info->base_clock;
3947 
3948 	/* div = osc/rate - 1
3949 	 *
3950 	 * Round div up if osc/rate is not integer to
3951 	 * force to next slowest rate.
3952 	 */
3953 
3954 	if (rate) {
3955 		div = osc/rate;
3956 		if (!(osc % rate) && div)
3957 			div--;
3958 		wr_reg16(info, BDR, (unsigned short)div);
3959 	}
3960 }
3961 
3962 static void rx_stop(struct slgt_info *info)
3963 {
3964 	unsigned short val;
3965 
3966 	/* disable and reset receiver */
3967 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3968 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3969 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3970 
3971 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3972 
3973 	/* clear pending rx interrupts */
3974 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3975 
3976 	rdma_reset(info);
3977 
3978 	info->rx_enabled = false;
3979 	info->rx_restart = false;
3980 }
3981 
3982 static void rx_start(struct slgt_info *info)
3983 {
3984 	unsigned short val;
3985 
3986 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3987 
3988 	/* clear pending rx overrun IRQ */
3989 	wr_reg16(info, SSR, IRQ_RXOVER);
3990 
3991 	/* reset and disable receiver */
3992 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3993 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3994 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3995 
3996 	rdma_reset(info);
3997 	reset_rbufs(info);
3998 
3999 	if (info->rx_pio) {
4000 		/* rx request when rx FIFO not empty */
4001 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
4002 		slgt_irq_on(info, IRQ_RXDATA);
4003 		if (info->params.mode == MGSL_MODE_ASYNC) {
4004 			/* enable saving of rx status */
4005 			wr_reg32(info, RDCSR, BIT6);
4006 		}
4007 	} else {
4008 		/* rx request when rx FIFO half full */
4009 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
4010 		/* set 1st descriptor address */
4011 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
4012 
4013 		if (info->params.mode != MGSL_MODE_ASYNC) {
4014 			/* enable rx DMA and DMA interrupt */
4015 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
4016 		} else {
4017 			/* enable saving of rx status, rx DMA and DMA interrupt */
4018 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
4019 		}
4020 	}
4021 
4022 	slgt_irq_on(info, IRQ_RXOVER);
4023 
4024 	/* enable receiver */
4025 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
4026 
4027 	info->rx_restart = false;
4028 	info->rx_enabled = true;
4029 }
4030 
4031 static void tx_start(struct slgt_info *info)
4032 {
4033 	if (!info->tx_enabled) {
4034 		wr_reg16(info, TCR,
4035 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
4036 		info->tx_enabled = true;
4037 	}
4038 
4039 	if (desc_count(info->tbufs[info->tbuf_start])) {
4040 		info->drop_rts_on_tx_done = false;
4041 
4042 		if (info->params.mode != MGSL_MODE_ASYNC) {
4043 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
4044 				get_signals(info);
4045 				if (!(info->signals & SerialSignal_RTS)) {
4046 					info->signals |= SerialSignal_RTS;
4047 					set_signals(info);
4048 					info->drop_rts_on_tx_done = true;
4049 				}
4050 			}
4051 
4052 			slgt_irq_off(info, IRQ_TXDATA);
4053 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
4054 			/* clear tx idle and underrun status bits */
4055 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4056 		} else {
4057 			slgt_irq_off(info, IRQ_TXDATA);
4058 			slgt_irq_on(info, IRQ_TXIDLE);
4059 			/* clear tx idle status bit */
4060 			wr_reg16(info, SSR, IRQ_TXIDLE);
4061 		}
4062 		/* set 1st descriptor address and start DMA */
4063 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
4064 		wr_reg32(info, TDCSR, BIT2 + BIT0);
4065 		info->tx_active = true;
4066 	}
4067 }
4068 
4069 static void tx_stop(struct slgt_info *info)
4070 {
4071 	unsigned short val;
4072 
4073 	del_timer(&info->tx_timer);
4074 
4075 	tdma_reset(info);
4076 
4077 	/* reset and disable transmitter */
4078 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
4079 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
4080 
4081 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
4082 
4083 	/* clear tx idle and underrun status bit */
4084 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4085 
4086 	reset_tbufs(info);
4087 
4088 	info->tx_enabled = false;
4089 	info->tx_active = false;
4090 }
4091 
4092 static void reset_port(struct slgt_info *info)
4093 {
4094 	if (!info->reg_addr)
4095 		return;
4096 
4097 	tx_stop(info);
4098 	rx_stop(info);
4099 
4100 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4101 	set_signals(info);
4102 
4103 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4104 }
4105 
4106 static void reset_adapter(struct slgt_info *info)
4107 {
4108 	int i;
4109 	for (i=0; i < info->port_count; ++i) {
4110 		if (info->port_array[i])
4111 			reset_port(info->port_array[i]);
4112 	}
4113 }
4114 
4115 static void async_mode(struct slgt_info *info)
4116 {
4117   	unsigned short val;
4118 
4119 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4120 	tx_stop(info);
4121 	rx_stop(info);
4122 
4123 	/* TCR (tx control)
4124 	 *
4125 	 * 15..13  mode, 010=async
4126 	 * 12..10  encoding, 000=NRZ
4127 	 * 09      parity enable
4128 	 * 08      1=odd parity, 0=even parity
4129 	 * 07      1=RTS driver control
4130 	 * 06      1=break enable
4131 	 * 05..04  character length
4132 	 *         00=5 bits
4133 	 *         01=6 bits
4134 	 *         10=7 bits
4135 	 *         11=8 bits
4136 	 * 03      0=1 stop bit, 1=2 stop bits
4137 	 * 02      reset
4138 	 * 01      enable
4139 	 * 00      auto-CTS enable
4140 	 */
4141 	val = 0x4000;
4142 
4143 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4144 		val |= BIT7;
4145 
4146 	if (info->params.parity != ASYNC_PARITY_NONE) {
4147 		val |= BIT9;
4148 		if (info->params.parity == ASYNC_PARITY_ODD)
4149 			val |= BIT8;
4150 	}
4151 
4152 	switch (info->params.data_bits)
4153 	{
4154 	case 6: val |= BIT4; break;
4155 	case 7: val |= BIT5; break;
4156 	case 8: val |= BIT5 + BIT4; break;
4157 	}
4158 
4159 	if (info->params.stop_bits != 1)
4160 		val |= BIT3;
4161 
4162 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4163 		val |= BIT0;
4164 
4165 	wr_reg16(info, TCR, val);
4166 
4167 	/* RCR (rx control)
4168 	 *
4169 	 * 15..13  mode, 010=async
4170 	 * 12..10  encoding, 000=NRZ
4171 	 * 09      parity enable
4172 	 * 08      1=odd parity, 0=even parity
4173 	 * 07..06  reserved, must be 0
4174 	 * 05..04  character length
4175 	 *         00=5 bits
4176 	 *         01=6 bits
4177 	 *         10=7 bits
4178 	 *         11=8 bits
4179 	 * 03      reserved, must be zero
4180 	 * 02      reset
4181 	 * 01      enable
4182 	 * 00      auto-DCD enable
4183 	 */
4184 	val = 0x4000;
4185 
4186 	if (info->params.parity != ASYNC_PARITY_NONE) {
4187 		val |= BIT9;
4188 		if (info->params.parity == ASYNC_PARITY_ODD)
4189 			val |= BIT8;
4190 	}
4191 
4192 	switch (info->params.data_bits)
4193 	{
4194 	case 6: val |= BIT4; break;
4195 	case 7: val |= BIT5; break;
4196 	case 8: val |= BIT5 + BIT4; break;
4197 	}
4198 
4199 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4200 		val |= BIT0;
4201 
4202 	wr_reg16(info, RCR, val);
4203 
4204 	/* CCR (clock control)
4205 	 *
4206 	 * 07..05  011 = tx clock source is BRG/16
4207 	 * 04..02  010 = rx clock source is BRG
4208 	 * 01      0 = auxclk disabled
4209 	 * 00      1 = BRG enabled
4210 	 *
4211 	 * 0110 1001
4212 	 */
4213 	wr_reg8(info, CCR, 0x69);
4214 
4215 	msc_set_vcr(info);
4216 
4217 	/* SCR (serial control)
4218 	 *
4219 	 * 15  1=tx req on FIFO half empty
4220 	 * 14  1=rx req on FIFO half full
4221 	 * 13  tx data  IRQ enable
4222 	 * 12  tx idle  IRQ enable
4223 	 * 11  rx break on IRQ enable
4224 	 * 10  rx data  IRQ enable
4225 	 * 09  rx break off IRQ enable
4226 	 * 08  overrun  IRQ enable
4227 	 * 07  DSR      IRQ enable
4228 	 * 06  CTS      IRQ enable
4229 	 * 05  DCD      IRQ enable
4230 	 * 04  RI       IRQ enable
4231 	 * 03  0=16x sampling, 1=8x sampling
4232 	 * 02  1=txd->rxd internal loopback enable
4233 	 * 01  reserved, must be zero
4234 	 * 00  1=master IRQ enable
4235 	 */
4236 	val = BIT15 + BIT14 + BIT0;
4237 	/* JCR[8] : 1 = x8 async mode feature available */
4238 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4239 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4240 	     (info->base_clock % (info->params.data_rate * 16)))) {
4241 		/* use 8x sampling */
4242 		val |= BIT3;
4243 		set_rate(info, info->params.data_rate * 8);
4244 	} else {
4245 		/* use 16x sampling */
4246 		set_rate(info, info->params.data_rate * 16);
4247 	}
4248 	wr_reg16(info, SCR, val);
4249 
4250 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4251 
4252 	if (info->params.loopback)
4253 		enable_loopback(info);
4254 }
4255 
4256 static void sync_mode(struct slgt_info *info)
4257 {
4258 	unsigned short val;
4259 
4260 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4261 	tx_stop(info);
4262 	rx_stop(info);
4263 
4264 	/* TCR (tx control)
4265 	 *
4266 	 * 15..13  mode
4267 	 *         000=HDLC/SDLC
4268 	 *         001=raw bit synchronous
4269 	 *         010=asynchronous/isochronous
4270 	 *         011=monosync byte synchronous
4271 	 *         100=bisync byte synchronous
4272 	 *         101=xsync byte synchronous
4273 	 * 12..10  encoding
4274 	 * 09      CRC enable
4275 	 * 08      CRC32
4276 	 * 07      1=RTS driver control
4277 	 * 06      preamble enable
4278 	 * 05..04  preamble length
4279 	 * 03      share open/close flag
4280 	 * 02      reset
4281 	 * 01      enable
4282 	 * 00      auto-CTS enable
4283 	 */
4284 	val = BIT2;
4285 
4286 	switch(info->params.mode) {
4287 	case MGSL_MODE_XSYNC:
4288 		val |= BIT15 + BIT13;
4289 		break;
4290 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4291 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4292 	case MGSL_MODE_RAW:      val |= BIT13; break;
4293 	}
4294 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4295 		val |= BIT7;
4296 
4297 	switch(info->params.encoding)
4298 	{
4299 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4300 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4301 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4302 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4303 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4304 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4305 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4306 	}
4307 
4308 	switch (info->params.crc_type & HDLC_CRC_MASK)
4309 	{
4310 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4311 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4312 	}
4313 
4314 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4315 		val |= BIT6;
4316 
4317 	switch (info->params.preamble_length)
4318 	{
4319 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4320 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4321 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4322 	}
4323 
4324 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4325 		val |= BIT0;
4326 
4327 	wr_reg16(info, TCR, val);
4328 
4329 	/* TPR (transmit preamble) */
4330 
4331 	switch (info->params.preamble)
4332 	{
4333 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4334 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4335 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4336 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4337 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4338 	default:                          val = 0x7e; break;
4339 	}
4340 	wr_reg8(info, TPR, (unsigned char)val);
4341 
4342 	/* RCR (rx control)
4343 	 *
4344 	 * 15..13  mode
4345 	 *         000=HDLC/SDLC
4346 	 *         001=raw bit synchronous
4347 	 *         010=asynchronous/isochronous
4348 	 *         011=monosync byte synchronous
4349 	 *         100=bisync byte synchronous
4350 	 *         101=xsync byte synchronous
4351 	 * 12..10  encoding
4352 	 * 09      CRC enable
4353 	 * 08      CRC32
4354 	 * 07..03  reserved, must be 0
4355 	 * 02      reset
4356 	 * 01      enable
4357 	 * 00      auto-DCD enable
4358 	 */
4359 	val = 0;
4360 
4361 	switch(info->params.mode) {
4362 	case MGSL_MODE_XSYNC:
4363 		val |= BIT15 + BIT13;
4364 		break;
4365 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4366 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4367 	case MGSL_MODE_RAW:      val |= BIT13; break;
4368 	}
4369 
4370 	switch(info->params.encoding)
4371 	{
4372 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4373 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4374 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4375 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4376 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4377 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4378 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4379 	}
4380 
4381 	switch (info->params.crc_type & HDLC_CRC_MASK)
4382 	{
4383 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4384 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4385 	}
4386 
4387 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4388 		val |= BIT0;
4389 
4390 	wr_reg16(info, RCR, val);
4391 
4392 	/* CCR (clock control)
4393 	 *
4394 	 * 07..05  tx clock source
4395 	 * 04..02  rx clock source
4396 	 * 01      auxclk enable
4397 	 * 00      BRG enable
4398 	 */
4399 	val = 0;
4400 
4401 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4402 	{
4403 		// when RxC source is DPLL, BRG generates 16X DPLL
4404 		// reference clock, so take TxC from BRG/16 to get
4405 		// transmit clock at actual data rate
4406 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4407 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4408 		else
4409 			val |= BIT6;	/* 010, txclk = BRG */
4410 	}
4411 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4412 		val |= BIT7;	/* 100, txclk = DPLL Input */
4413 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4414 		val |= BIT5;	/* 001, txclk = RXC Input */
4415 
4416 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4417 		val |= BIT3;	/* 010, rxclk = BRG */
4418 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4419 		val |= BIT4;	/* 100, rxclk = DPLL */
4420 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4421 		val |= BIT2;	/* 001, rxclk = TXC Input */
4422 
4423 	if (info->params.clock_speed)
4424 		val |= BIT1 + BIT0;
4425 
4426 	wr_reg8(info, CCR, (unsigned char)val);
4427 
4428 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4429 	{
4430 		// program DPLL mode
4431 		switch(info->params.encoding)
4432 		{
4433 		case HDLC_ENCODING_BIPHASE_MARK:
4434 		case HDLC_ENCODING_BIPHASE_SPACE:
4435 			val = BIT7; break;
4436 		case HDLC_ENCODING_BIPHASE_LEVEL:
4437 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4438 			val = BIT7 + BIT6; break;
4439 		default: val = BIT6;	// NRZ encodings
4440 		}
4441 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4442 
4443 		// DPLL requires a 16X reference clock from BRG
4444 		set_rate(info, info->params.clock_speed * 16);
4445 	}
4446 	else
4447 		set_rate(info, info->params.clock_speed);
4448 
4449 	tx_set_idle(info);
4450 
4451 	msc_set_vcr(info);
4452 
4453 	/* SCR (serial control)
4454 	 *
4455 	 * 15  1=tx req on FIFO half empty
4456 	 * 14  1=rx req on FIFO half full
4457 	 * 13  tx data  IRQ enable
4458 	 * 12  tx idle  IRQ enable
4459 	 * 11  underrun IRQ enable
4460 	 * 10  rx data  IRQ enable
4461 	 * 09  rx idle  IRQ enable
4462 	 * 08  overrun  IRQ enable
4463 	 * 07  DSR      IRQ enable
4464 	 * 06  CTS      IRQ enable
4465 	 * 05  DCD      IRQ enable
4466 	 * 04  RI       IRQ enable
4467 	 * 03  reserved, must be zero
4468 	 * 02  1=txd->rxd internal loopback enable
4469 	 * 01  reserved, must be zero
4470 	 * 00  1=master IRQ enable
4471 	 */
4472 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4473 
4474 	if (info->params.loopback)
4475 		enable_loopback(info);
4476 }
4477 
4478 /*
4479  *  set transmit idle mode
4480  */
4481 static void tx_set_idle(struct slgt_info *info)
4482 {
4483 	unsigned char val;
4484 	unsigned short tcr;
4485 
4486 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4487 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4488 	 */
4489 	tcr = rd_reg16(info, TCR);
4490 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4491 		/* disable preamble, set idle size to 16 bits */
4492 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4493 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4494 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4495 	} else if (!(tcr & BIT6)) {
4496 		/* preamble is disabled, set idle size to 8 bits */
4497 		tcr &= ~(BIT5 + BIT4);
4498 	}
4499 	wr_reg16(info, TCR, tcr);
4500 
4501 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4502 		/* LSB of custom tx idle specified in tx idle register */
4503 		val = (unsigned char)(info->idle_mode & 0xff);
4504 	} else {
4505 		/* standard 8 bit idle patterns */
4506 		switch(info->idle_mode)
4507 		{
4508 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4509 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4510 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4511 		case HDLC_TXIDLE_ZEROS:
4512 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4513 		default:                         val = 0xff;
4514 		}
4515 	}
4516 
4517 	wr_reg8(info, TIR, val);
4518 }
4519 
4520 /*
4521  * get state of V24 status (input) signals
4522  */
4523 static void get_signals(struct slgt_info *info)
4524 {
4525 	unsigned short status = rd_reg16(info, SSR);
4526 
4527 	/* clear all serial signals except RTS and DTR */
4528 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4529 
4530 	if (status & BIT3)
4531 		info->signals |= SerialSignal_DSR;
4532 	if (status & BIT2)
4533 		info->signals |= SerialSignal_CTS;
4534 	if (status & BIT1)
4535 		info->signals |= SerialSignal_DCD;
4536 	if (status & BIT0)
4537 		info->signals |= SerialSignal_RI;
4538 }
4539 
4540 /*
4541  * set V.24 Control Register based on current configuration
4542  */
4543 static void msc_set_vcr(struct slgt_info *info)
4544 {
4545 	unsigned char val = 0;
4546 
4547 	/* VCR (V.24 control)
4548 	 *
4549 	 * 07..04  serial IF select
4550 	 * 03      DTR
4551 	 * 02      RTS
4552 	 * 01      LL
4553 	 * 00      RL
4554 	 */
4555 
4556 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4557 	{
4558 	case MGSL_INTERFACE_RS232:
4559 		val |= BIT5; /* 0010 */
4560 		break;
4561 	case MGSL_INTERFACE_V35:
4562 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4563 		break;
4564 	case MGSL_INTERFACE_RS422:
4565 		val |= BIT6; /* 0100 */
4566 		break;
4567 	}
4568 
4569 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4570 		val |= BIT4;
4571 	if (info->signals & SerialSignal_DTR)
4572 		val |= BIT3;
4573 	if (info->signals & SerialSignal_RTS)
4574 		val |= BIT2;
4575 	if (info->if_mode & MGSL_INTERFACE_LL)
4576 		val |= BIT1;
4577 	if (info->if_mode & MGSL_INTERFACE_RL)
4578 		val |= BIT0;
4579 	wr_reg8(info, VCR, val);
4580 }
4581 
4582 /*
4583  * set state of V24 control (output) signals
4584  */
4585 static void set_signals(struct slgt_info *info)
4586 {
4587 	unsigned char val = rd_reg8(info, VCR);
4588 	if (info->signals & SerialSignal_DTR)
4589 		val |= BIT3;
4590 	else
4591 		val &= ~BIT3;
4592 	if (info->signals & SerialSignal_RTS)
4593 		val |= BIT2;
4594 	else
4595 		val &= ~BIT2;
4596 	wr_reg8(info, VCR, val);
4597 }
4598 
4599 /*
4600  * free range of receive DMA buffers (i to last)
4601  */
4602 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4603 {
4604 	int done = 0;
4605 
4606 	while(!done) {
4607 		/* reset current buffer for reuse */
4608 		info->rbufs[i].status = 0;
4609 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4610 		if (i == last)
4611 			done = 1;
4612 		if (++i == info->rbuf_count)
4613 			i = 0;
4614 	}
4615 	info->rbuf_current = i;
4616 }
4617 
4618 /*
4619  * mark all receive DMA buffers as free
4620  */
4621 static void reset_rbufs(struct slgt_info *info)
4622 {
4623 	free_rbufs(info, 0, info->rbuf_count - 1);
4624 	info->rbuf_fill_index = 0;
4625 	info->rbuf_fill_count = 0;
4626 }
4627 
4628 /*
4629  * pass receive HDLC frame to upper layer
4630  *
4631  * return true if frame available, otherwise false
4632  */
4633 static bool rx_get_frame(struct slgt_info *info)
4634 {
4635 	unsigned int start, end;
4636 	unsigned short status;
4637 	unsigned int framesize = 0;
4638 	unsigned long flags;
4639 	struct tty_struct *tty = info->port.tty;
4640 	unsigned char addr_field = 0xff;
4641 	unsigned int crc_size = 0;
4642 
4643 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4644 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4645 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4646 	}
4647 
4648 check_again:
4649 
4650 	framesize = 0;
4651 	addr_field = 0xff;
4652 	start = end = info->rbuf_current;
4653 
4654 	for (;;) {
4655 		if (!desc_complete(info->rbufs[end]))
4656 			goto cleanup;
4657 
4658 		if (framesize == 0 && info->params.addr_filter != 0xff)
4659 			addr_field = info->rbufs[end].buf[0];
4660 
4661 		framesize += desc_count(info->rbufs[end]);
4662 
4663 		if (desc_eof(info->rbufs[end]))
4664 			break;
4665 
4666 		if (++end == info->rbuf_count)
4667 			end = 0;
4668 
4669 		if (end == info->rbuf_current) {
4670 			if (info->rx_enabled){
4671 				spin_lock_irqsave(&info->lock,flags);
4672 				rx_start(info);
4673 				spin_unlock_irqrestore(&info->lock,flags);
4674 			}
4675 			goto cleanup;
4676 		}
4677 	}
4678 
4679 	/* status
4680 	 *
4681 	 * 15      buffer complete
4682 	 * 14..06  reserved
4683 	 * 05..04  residue
4684 	 * 02      eof (end of frame)
4685 	 * 01      CRC error
4686 	 * 00      abort
4687 	 */
4688 	status = desc_status(info->rbufs[end]);
4689 
4690 	/* ignore CRC bit if not using CRC (bit is undefined) */
4691 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4692 		status &= ~BIT1;
4693 
4694 	if (framesize == 0 ||
4695 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4696 		free_rbufs(info, start, end);
4697 		goto check_again;
4698 	}
4699 
4700 	if (framesize < (2 + crc_size) || status & BIT0) {
4701 		info->icount.rxshort++;
4702 		framesize = 0;
4703 	} else if (status & BIT1) {
4704 		info->icount.rxcrc++;
4705 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4706 			framesize = 0;
4707 	}
4708 
4709 #if SYNCLINK_GENERIC_HDLC
4710 	if (framesize == 0) {
4711 		info->netdev->stats.rx_errors++;
4712 		info->netdev->stats.rx_frame_errors++;
4713 	}
4714 #endif
4715 
4716 	DBGBH(("%s rx frame status=%04X size=%d\n",
4717 		info->device_name, status, framesize));
4718 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4719 
4720 	if (framesize) {
4721 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4722 			framesize -= crc_size;
4723 			crc_size = 0;
4724 		}
4725 
4726 		if (framesize > info->max_frame_size + crc_size)
4727 			info->icount.rxlong++;
4728 		else {
4729 			/* copy dma buffer(s) to contiguous temp buffer */
4730 			int copy_count = framesize;
4731 			int i = start;
4732 			unsigned char *p = info->tmp_rbuf;
4733 			info->tmp_rbuf_count = framesize;
4734 
4735 			info->icount.rxok++;
4736 
4737 			while(copy_count) {
4738 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4739 				memcpy(p, info->rbufs[i].buf, partial_count);
4740 				p += partial_count;
4741 				copy_count -= partial_count;
4742 				if (++i == info->rbuf_count)
4743 					i = 0;
4744 			}
4745 
4746 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4747 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4748 				framesize++;
4749 			}
4750 
4751 #if SYNCLINK_GENERIC_HDLC
4752 			if (info->netcount)
4753 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4754 			else
4755 #endif
4756 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4757 		}
4758 	}
4759 	free_rbufs(info, start, end);
4760 	return true;
4761 
4762 cleanup:
4763 	return false;
4764 }
4765 
4766 /*
4767  * pass receive buffer (RAW synchronous mode) to tty layer
4768  * return true if buffer available, otherwise false
4769  */
4770 static bool rx_get_buf(struct slgt_info *info)
4771 {
4772 	unsigned int i = info->rbuf_current;
4773 	unsigned int count;
4774 
4775 	if (!desc_complete(info->rbufs[i]))
4776 		return false;
4777 	count = desc_count(info->rbufs[i]);
4778 	switch(info->params.mode) {
4779 	case MGSL_MODE_MONOSYNC:
4780 	case MGSL_MODE_BISYNC:
4781 	case MGSL_MODE_XSYNC:
4782 		/* ignore residue in byte synchronous modes */
4783 		if (desc_residue(info->rbufs[i]))
4784 			count--;
4785 		break;
4786 	}
4787 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4788 	DBGINFO(("rx_get_buf size=%d\n", count));
4789 	if (count)
4790 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4791 				  info->flag_buf, count);
4792 	free_rbufs(info, i, i);
4793 	return true;
4794 }
4795 
4796 static void reset_tbufs(struct slgt_info *info)
4797 {
4798 	unsigned int i;
4799 	info->tbuf_current = 0;
4800 	for (i=0 ; i < info->tbuf_count ; i++) {
4801 		info->tbufs[i].status = 0;
4802 		info->tbufs[i].count  = 0;
4803 	}
4804 }
4805 
4806 /*
4807  * return number of free transmit DMA buffers
4808  */
4809 static unsigned int free_tbuf_count(struct slgt_info *info)
4810 {
4811 	unsigned int count = 0;
4812 	unsigned int i = info->tbuf_current;
4813 
4814 	do
4815 	{
4816 		if (desc_count(info->tbufs[i]))
4817 			break; /* buffer in use */
4818 		++count;
4819 		if (++i == info->tbuf_count)
4820 			i=0;
4821 	} while (i != info->tbuf_current);
4822 
4823 	/* if tx DMA active, last zero count buffer is in use */
4824 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4825 		--count;
4826 
4827 	return count;
4828 }
4829 
4830 /*
4831  * return number of bytes in unsent transmit DMA buffers
4832  * and the serial controller tx FIFO
4833  */
4834 static unsigned int tbuf_bytes(struct slgt_info *info)
4835 {
4836 	unsigned int total_count = 0;
4837 	unsigned int i = info->tbuf_current;
4838 	unsigned int reg_value;
4839 	unsigned int count;
4840 	unsigned int active_buf_count = 0;
4841 
4842 	/*
4843 	 * Add descriptor counts for all tx DMA buffers.
4844 	 * If count is zero (cleared by DMA controller after read),
4845 	 * the buffer is complete or is actively being read from.
4846 	 *
4847 	 * Record buf_count of last buffer with zero count starting
4848 	 * from current ring position. buf_count is mirror
4849 	 * copy of count and is not cleared by serial controller.
4850 	 * If DMA controller is active, that buffer is actively
4851 	 * being read so add to total.
4852 	 */
4853 	do {
4854 		count = desc_count(info->tbufs[i]);
4855 		if (count)
4856 			total_count += count;
4857 		else if (!total_count)
4858 			active_buf_count = info->tbufs[i].buf_count;
4859 		if (++i == info->tbuf_count)
4860 			i = 0;
4861 	} while (i != info->tbuf_current);
4862 
4863 	/* read tx DMA status register */
4864 	reg_value = rd_reg32(info, TDCSR);
4865 
4866 	/* if tx DMA active, last zero count buffer is in use */
4867 	if (reg_value & BIT0)
4868 		total_count += active_buf_count;
4869 
4870 	/* add tx FIFO count = reg_value[15..8] */
4871 	total_count += (reg_value >> 8) & 0xff;
4872 
4873 	/* if transmitter active add one byte for shift register */
4874 	if (info->tx_active)
4875 		total_count++;
4876 
4877 	return total_count;
4878 }
4879 
4880 /*
4881  * load data into transmit DMA buffer ring and start transmitter if needed
4882  * return true if data accepted, otherwise false (buffers full)
4883  */
4884 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4885 {
4886 	unsigned short count;
4887 	unsigned int i;
4888 	struct slgt_desc *d;
4889 
4890 	/* check required buffer space */
4891 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4892 		return false;
4893 
4894 	DBGDATA(info, buf, size, "tx");
4895 
4896 	/*
4897 	 * copy data to one or more DMA buffers in circular ring
4898 	 * tbuf_start   = first buffer for this data
4899 	 * tbuf_current = next free buffer
4900 	 *
4901 	 * Copy all data before making data visible to DMA controller by
4902 	 * setting descriptor count of the first buffer.
4903 	 * This prevents an active DMA controller from reading the first DMA
4904 	 * buffers of a frame and stopping before the final buffers are filled.
4905 	 */
4906 
4907 	info->tbuf_start = i = info->tbuf_current;
4908 
4909 	while (size) {
4910 		d = &info->tbufs[i];
4911 
4912 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4913 		memcpy(d->buf, buf, count);
4914 
4915 		size -= count;
4916 		buf  += count;
4917 
4918 		/*
4919 		 * set EOF bit for last buffer of HDLC frame or
4920 		 * for every buffer in raw mode
4921 		 */
4922 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4923 		    info->params.mode == MGSL_MODE_RAW)
4924 			set_desc_eof(*d, 1);
4925 		else
4926 			set_desc_eof(*d, 0);
4927 
4928 		/* set descriptor count for all but first buffer */
4929 		if (i != info->tbuf_start)
4930 			set_desc_count(*d, count);
4931 		d->buf_count = count;
4932 
4933 		if (++i == info->tbuf_count)
4934 			i = 0;
4935 	}
4936 
4937 	info->tbuf_current = i;
4938 
4939 	/* set first buffer count to make new data visible to DMA controller */
4940 	d = &info->tbufs[info->tbuf_start];
4941 	set_desc_count(*d, d->buf_count);
4942 
4943 	/* start transmitter if needed and update transmit timeout */
4944 	if (!info->tx_active)
4945 		tx_start(info);
4946 	update_tx_timer(info);
4947 
4948 	return true;
4949 }
4950 
4951 static int register_test(struct slgt_info *info)
4952 {
4953 	static unsigned short patterns[] =
4954 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4955 	static unsigned int count = ARRAY_SIZE(patterns);
4956 	unsigned int i;
4957 	int rc = 0;
4958 
4959 	for (i=0 ; i < count ; i++) {
4960 		wr_reg16(info, TIR, patterns[i]);
4961 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4962 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4963 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4964 			rc = -ENODEV;
4965 			break;
4966 		}
4967 	}
4968 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4969 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4970 	return rc;
4971 }
4972 
4973 static int irq_test(struct slgt_info *info)
4974 {
4975 	unsigned long timeout;
4976 	unsigned long flags;
4977 	struct tty_struct *oldtty = info->port.tty;
4978 	u32 speed = info->params.data_rate;
4979 
4980 	info->params.data_rate = 921600;
4981 	info->port.tty = NULL;
4982 
4983 	spin_lock_irqsave(&info->lock, flags);
4984 	async_mode(info);
4985 	slgt_irq_on(info, IRQ_TXIDLE);
4986 
4987 	/* enable transmitter */
4988 	wr_reg16(info, TCR,
4989 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4990 
4991 	/* write one byte and wait for tx idle */
4992 	wr_reg16(info, TDR, 0);
4993 
4994 	/* assume failure */
4995 	info->init_error = DiagStatus_IrqFailure;
4996 	info->irq_occurred = false;
4997 
4998 	spin_unlock_irqrestore(&info->lock, flags);
4999 
5000 	timeout=100;
5001 	while(timeout-- && !info->irq_occurred)
5002 		msleep_interruptible(10);
5003 
5004 	spin_lock_irqsave(&info->lock,flags);
5005 	reset_port(info);
5006 	spin_unlock_irqrestore(&info->lock,flags);
5007 
5008 	info->params.data_rate = speed;
5009 	info->port.tty = oldtty;
5010 
5011 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
5012 	return info->irq_occurred ? 0 : -ENODEV;
5013 }
5014 
5015 static int loopback_test_rx(struct slgt_info *info)
5016 {
5017 	unsigned char *src, *dest;
5018 	int count;
5019 
5020 	if (desc_complete(info->rbufs[0])) {
5021 		count = desc_count(info->rbufs[0]);
5022 		src   = info->rbufs[0].buf;
5023 		dest  = info->tmp_rbuf;
5024 
5025 		for( ; count ; count-=2, src+=2) {
5026 			/* src=data byte (src+1)=status byte */
5027 			if (!(*(src+1) & (BIT9 + BIT8))) {
5028 				*dest = *src;
5029 				dest++;
5030 				info->tmp_rbuf_count++;
5031 			}
5032 		}
5033 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
5034 		return 1;
5035 	}
5036 	return 0;
5037 }
5038 
5039 static int loopback_test(struct slgt_info *info)
5040 {
5041 #define TESTFRAMESIZE 20
5042 
5043 	unsigned long timeout;
5044 	u16 count = TESTFRAMESIZE;
5045 	unsigned char buf[TESTFRAMESIZE];
5046 	int rc = -ENODEV;
5047 	unsigned long flags;
5048 
5049 	struct tty_struct *oldtty = info->port.tty;
5050 	MGSL_PARAMS params;
5051 
5052 	memcpy(&params, &info->params, sizeof(params));
5053 
5054 	info->params.mode = MGSL_MODE_ASYNC;
5055 	info->params.data_rate = 921600;
5056 	info->params.loopback = 1;
5057 	info->port.tty = NULL;
5058 
5059 	/* build and send transmit frame */
5060 	for (count = 0; count < TESTFRAMESIZE; ++count)
5061 		buf[count] = (unsigned char)count;
5062 
5063 	info->tmp_rbuf_count = 0;
5064 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
5065 
5066 	/* program hardware for HDLC and enabled receiver */
5067 	spin_lock_irqsave(&info->lock,flags);
5068 	async_mode(info);
5069 	rx_start(info);
5070 	tx_load(info, buf, count);
5071 	spin_unlock_irqrestore(&info->lock, flags);
5072 
5073 	/* wait for receive complete */
5074 	for (timeout = 100; timeout; --timeout) {
5075 		msleep_interruptible(10);
5076 		if (loopback_test_rx(info)) {
5077 			rc = 0;
5078 			break;
5079 		}
5080 	}
5081 
5082 	/* verify received frame length and contents */
5083 	if (!rc && (info->tmp_rbuf_count != count ||
5084 		  memcmp(buf, info->tmp_rbuf, count))) {
5085 		rc = -ENODEV;
5086 	}
5087 
5088 	spin_lock_irqsave(&info->lock,flags);
5089 	reset_adapter(info);
5090 	spin_unlock_irqrestore(&info->lock,flags);
5091 
5092 	memcpy(&info->params, &params, sizeof(info->params));
5093 	info->port.tty = oldtty;
5094 
5095 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5096 	return rc;
5097 }
5098 
5099 static int adapter_test(struct slgt_info *info)
5100 {
5101 	DBGINFO(("testing %s\n", info->device_name));
5102 	if (register_test(info) < 0) {
5103 		printk("register test failure %s addr=%08X\n",
5104 			info->device_name, info->phys_reg_addr);
5105 	} else if (irq_test(info) < 0) {
5106 		printk("IRQ test failure %s IRQ=%d\n",
5107 			info->device_name, info->irq_level);
5108 	} else if (loopback_test(info) < 0) {
5109 		printk("loopback test failure %s\n", info->device_name);
5110 	}
5111 	return info->init_error;
5112 }
5113 
5114 /*
5115  * transmit timeout handler
5116  */
5117 static void tx_timeout(unsigned long context)
5118 {
5119 	struct slgt_info *info = (struct slgt_info*)context;
5120 	unsigned long flags;
5121 
5122 	DBGINFO(("%s tx_timeout\n", info->device_name));
5123 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5124 		info->icount.txtimeout++;
5125 	}
5126 	spin_lock_irqsave(&info->lock,flags);
5127 	tx_stop(info);
5128 	spin_unlock_irqrestore(&info->lock,flags);
5129 
5130 #if SYNCLINK_GENERIC_HDLC
5131 	if (info->netcount)
5132 		hdlcdev_tx_done(info);
5133 	else
5134 #endif
5135 		bh_transmit(info);
5136 }
5137 
5138 /*
5139  * receive buffer polling timer
5140  */
5141 static void rx_timeout(unsigned long context)
5142 {
5143 	struct slgt_info *info = (struct slgt_info*)context;
5144 	unsigned long flags;
5145 
5146 	DBGINFO(("%s rx_timeout\n", info->device_name));
5147 	spin_lock_irqsave(&info->lock, flags);
5148 	info->pending_bh |= BH_RECEIVE;
5149 	spin_unlock_irqrestore(&info->lock, flags);
5150 	bh_handler(&info->task);
5151 }
5152 
5153