xref: /linux/drivers/tty/synclink_gt.c (revision 807c8d81f4ec441241cafa3034c58df721fee869)
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 (info->port.flags & ASYNC_INITIALIZED)
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 (!(info->port.flags & ASYNC_INITIALIZED))
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 	dev->trans_start = jiffies;
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 	dev->trans_start = jiffies;
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 (info->port.flags & ASYNC_CHECK_CD) {
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 (info->port.flags & ASYNC_INITIALIZED)
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 	info->port.flags |= ASYNC_INITIALIZED;
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 (!(info->port.flags & ASYNC_INITIALIZED))
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 	info->port.flags &= ~ASYNC_INITIALIZED;
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 
2581 	if (cflag & CLOCAL)
2582 		info->port.flags &= ~ASYNC_CHECK_CD;
2583 	else
2584 		info->port.flags |= ASYNC_CHECK_CD;
2585 
2586 	/* process tty input control flags */
2587 
2588 	info->read_status_mask = IRQ_RXOVER;
2589 	if (I_INPCK(info->port.tty))
2590 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2591  	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2592  		info->read_status_mask |= MASK_BREAK;
2593 	if (I_IGNPAR(info->port.tty))
2594 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2595 	if (I_IGNBRK(info->port.tty)) {
2596 		info->ignore_status_mask |= MASK_BREAK;
2597 		/* If ignoring parity and break indicators, ignore
2598 		 * overruns too.  (For real raw support).
2599 		 */
2600 		if (I_IGNPAR(info->port.tty))
2601 			info->ignore_status_mask |= MASK_OVERRUN;
2602 	}
2603 
2604 	program_hw(info);
2605 }
2606 
2607 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2608 {
2609 	DBGINFO(("%s get_stats\n",  info->device_name));
2610 	if (!user_icount) {
2611 		memset(&info->icount, 0, sizeof(info->icount));
2612 	} else {
2613 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2614 			return -EFAULT;
2615 	}
2616 	return 0;
2617 }
2618 
2619 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2620 {
2621 	DBGINFO(("%s get_params\n", info->device_name));
2622 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2623 		return -EFAULT;
2624 	return 0;
2625 }
2626 
2627 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2628 {
2629  	unsigned long flags;
2630 	MGSL_PARAMS tmp_params;
2631 
2632 	DBGINFO(("%s set_params\n", info->device_name));
2633 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2634 		return -EFAULT;
2635 
2636 	spin_lock_irqsave(&info->lock, flags);
2637 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2638 		info->base_clock = tmp_params.clock_speed;
2639 	else
2640 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2641 	spin_unlock_irqrestore(&info->lock, flags);
2642 
2643 	program_hw(info);
2644 
2645 	return 0;
2646 }
2647 
2648 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2649 {
2650 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2651 	if (put_user(info->idle_mode, idle_mode))
2652 		return -EFAULT;
2653 	return 0;
2654 }
2655 
2656 static int set_txidle(struct slgt_info *info, int idle_mode)
2657 {
2658  	unsigned long flags;
2659 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2660 	spin_lock_irqsave(&info->lock,flags);
2661 	info->idle_mode = idle_mode;
2662 	if (info->params.mode != MGSL_MODE_ASYNC)
2663 		tx_set_idle(info);
2664 	spin_unlock_irqrestore(&info->lock,flags);
2665 	return 0;
2666 }
2667 
2668 static int tx_enable(struct slgt_info *info, int enable)
2669 {
2670  	unsigned long flags;
2671 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2672 	spin_lock_irqsave(&info->lock,flags);
2673 	if (enable) {
2674 		if (!info->tx_enabled)
2675 			tx_start(info);
2676 	} else {
2677 		if (info->tx_enabled)
2678 			tx_stop(info);
2679 	}
2680 	spin_unlock_irqrestore(&info->lock,flags);
2681 	return 0;
2682 }
2683 
2684 /*
2685  * abort transmit HDLC frame
2686  */
2687 static int tx_abort(struct slgt_info *info)
2688 {
2689  	unsigned long flags;
2690 	DBGINFO(("%s tx_abort\n", info->device_name));
2691 	spin_lock_irqsave(&info->lock,flags);
2692 	tdma_reset(info);
2693 	spin_unlock_irqrestore(&info->lock,flags);
2694 	return 0;
2695 }
2696 
2697 static int rx_enable(struct slgt_info *info, int enable)
2698 {
2699  	unsigned long flags;
2700 	unsigned int rbuf_fill_level;
2701 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2702 	spin_lock_irqsave(&info->lock,flags);
2703 	/*
2704 	 * enable[31..16] = receive DMA buffer fill level
2705 	 * 0 = noop (leave fill level unchanged)
2706 	 * fill level must be multiple of 4 and <= buffer size
2707 	 */
2708 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2709 	if (rbuf_fill_level) {
2710 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2711 			spin_unlock_irqrestore(&info->lock, flags);
2712 			return -EINVAL;
2713 		}
2714 		info->rbuf_fill_level = rbuf_fill_level;
2715 		if (rbuf_fill_level < 128)
2716 			info->rx_pio = 1; /* PIO mode */
2717 		else
2718 			info->rx_pio = 0; /* DMA mode */
2719 		rx_stop(info); /* restart receiver to use new fill level */
2720 	}
2721 
2722 	/*
2723 	 * enable[1..0] = receiver enable command
2724 	 * 0 = disable
2725 	 * 1 = enable
2726 	 * 2 = enable or force hunt mode if already enabled
2727 	 */
2728 	enable &= 3;
2729 	if (enable) {
2730 		if (!info->rx_enabled)
2731 			rx_start(info);
2732 		else if (enable == 2) {
2733 			/* force hunt mode (write 1 to RCR[3]) */
2734 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2735 		}
2736 	} else {
2737 		if (info->rx_enabled)
2738 			rx_stop(info);
2739 	}
2740 	spin_unlock_irqrestore(&info->lock,flags);
2741 	return 0;
2742 }
2743 
2744 /*
2745  *  wait for specified event to occur
2746  */
2747 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2748 {
2749  	unsigned long flags;
2750 	int s;
2751 	int rc=0;
2752 	struct mgsl_icount cprev, cnow;
2753 	int events;
2754 	int mask;
2755 	struct	_input_signal_events oldsigs, newsigs;
2756 	DECLARE_WAITQUEUE(wait, current);
2757 
2758 	if (get_user(mask, mask_ptr))
2759 		return -EFAULT;
2760 
2761 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2762 
2763 	spin_lock_irqsave(&info->lock,flags);
2764 
2765 	/* return immediately if state matches requested events */
2766 	get_signals(info);
2767 	s = info->signals;
2768 
2769 	events = mask &
2770 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2771  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2772 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2773 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2774 	if (events) {
2775 		spin_unlock_irqrestore(&info->lock,flags);
2776 		goto exit;
2777 	}
2778 
2779 	/* save current irq counts */
2780 	cprev = info->icount;
2781 	oldsigs = info->input_signal_events;
2782 
2783 	/* enable hunt and idle irqs if needed */
2784 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2785 		unsigned short val = rd_reg16(info, SCR);
2786 		if (!(val & IRQ_RXIDLE))
2787 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2788 	}
2789 
2790 	set_current_state(TASK_INTERRUPTIBLE);
2791 	add_wait_queue(&info->event_wait_q, &wait);
2792 
2793 	spin_unlock_irqrestore(&info->lock,flags);
2794 
2795 	for(;;) {
2796 		schedule();
2797 		if (signal_pending(current)) {
2798 			rc = -ERESTARTSYS;
2799 			break;
2800 		}
2801 
2802 		/* get current irq counts */
2803 		spin_lock_irqsave(&info->lock,flags);
2804 		cnow = info->icount;
2805 		newsigs = info->input_signal_events;
2806 		set_current_state(TASK_INTERRUPTIBLE);
2807 		spin_unlock_irqrestore(&info->lock,flags);
2808 
2809 		/* if no change, wait aborted for some reason */
2810 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2811 		    newsigs.dsr_down == oldsigs.dsr_down &&
2812 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2813 		    newsigs.dcd_down == oldsigs.dcd_down &&
2814 		    newsigs.cts_up   == oldsigs.cts_up   &&
2815 		    newsigs.cts_down == oldsigs.cts_down &&
2816 		    newsigs.ri_up    == oldsigs.ri_up    &&
2817 		    newsigs.ri_down  == oldsigs.ri_down  &&
2818 		    cnow.exithunt    == cprev.exithunt   &&
2819 		    cnow.rxidle      == cprev.rxidle) {
2820 			rc = -EIO;
2821 			break;
2822 		}
2823 
2824 		events = mask &
2825 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2826 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2827 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2828 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2829 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2830 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2831 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2832 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2833 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2834 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2835 		if (events)
2836 			break;
2837 
2838 		cprev = cnow;
2839 		oldsigs = newsigs;
2840 	}
2841 
2842 	remove_wait_queue(&info->event_wait_q, &wait);
2843 	set_current_state(TASK_RUNNING);
2844 
2845 
2846 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2847 		spin_lock_irqsave(&info->lock,flags);
2848 		if (!waitqueue_active(&info->event_wait_q)) {
2849 			/* disable enable exit hunt mode/idle rcvd IRQs */
2850 			wr_reg16(info, SCR,
2851 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2852 		}
2853 		spin_unlock_irqrestore(&info->lock,flags);
2854 	}
2855 exit:
2856 	if (rc == 0)
2857 		rc = put_user(events, mask_ptr);
2858 	return rc;
2859 }
2860 
2861 static int get_interface(struct slgt_info *info, int __user *if_mode)
2862 {
2863 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2864 	if (put_user(info->if_mode, if_mode))
2865 		return -EFAULT;
2866 	return 0;
2867 }
2868 
2869 static int set_interface(struct slgt_info *info, int if_mode)
2870 {
2871  	unsigned long flags;
2872 	unsigned short val;
2873 
2874 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2875 	spin_lock_irqsave(&info->lock,flags);
2876 	info->if_mode = if_mode;
2877 
2878 	msc_set_vcr(info);
2879 
2880 	/* TCR (tx control) 07  1=RTS driver control */
2881 	val = rd_reg16(info, TCR);
2882 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2883 		val |= BIT7;
2884 	else
2885 		val &= ~BIT7;
2886 	wr_reg16(info, TCR, val);
2887 
2888 	spin_unlock_irqrestore(&info->lock,flags);
2889 	return 0;
2890 }
2891 
2892 static int get_xsync(struct slgt_info *info, int __user *xsync)
2893 {
2894 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2895 	if (put_user(info->xsync, xsync))
2896 		return -EFAULT;
2897 	return 0;
2898 }
2899 
2900 /*
2901  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2902  *
2903  * sync pattern is contained in least significant bytes of value
2904  * most significant byte of sync pattern is oldest (1st sent/detected)
2905  */
2906 static int set_xsync(struct slgt_info *info, int xsync)
2907 {
2908 	unsigned long flags;
2909 
2910 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2911 	spin_lock_irqsave(&info->lock, flags);
2912 	info->xsync = xsync;
2913 	wr_reg32(info, XSR, xsync);
2914 	spin_unlock_irqrestore(&info->lock, flags);
2915 	return 0;
2916 }
2917 
2918 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2919 {
2920 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2921 	if (put_user(info->xctrl, xctrl))
2922 		return -EFAULT;
2923 	return 0;
2924 }
2925 
2926 /*
2927  * set extended control options
2928  *
2929  * xctrl[31:19] reserved, must be zero
2930  * xctrl[18:17] extended sync pattern length in bytes
2931  *              00 = 1 byte  in xsr[7:0]
2932  *              01 = 2 bytes in xsr[15:0]
2933  *              10 = 3 bytes in xsr[23:0]
2934  *              11 = 4 bytes in xsr[31:0]
2935  * xctrl[16]    1 = enable terminal count, 0=disabled
2936  * xctrl[15:0]  receive terminal count for fixed length packets
2937  *              value is count minus one (0 = 1 byte packet)
2938  *              when terminal count is reached, receiver
2939  *              automatically returns to hunt mode and receive
2940  *              FIFO contents are flushed to DMA buffers with
2941  *              end of frame (EOF) status
2942  */
2943 static int set_xctrl(struct slgt_info *info, int xctrl)
2944 {
2945 	unsigned long flags;
2946 
2947 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2948 	spin_lock_irqsave(&info->lock, flags);
2949 	info->xctrl = xctrl;
2950 	wr_reg32(info, XCR, xctrl);
2951 	spin_unlock_irqrestore(&info->lock, flags);
2952 	return 0;
2953 }
2954 
2955 /*
2956  * set general purpose IO pin state and direction
2957  *
2958  * user_gpio fields:
2959  * state   each bit indicates a pin state
2960  * smask   set bit indicates pin state to set
2961  * dir     each bit indicates a pin direction (0=input, 1=output)
2962  * dmask   set bit indicates pin direction to set
2963  */
2964 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2965 {
2966  	unsigned long flags;
2967 	struct gpio_desc gpio;
2968 	__u32 data;
2969 
2970 	if (!info->gpio_present)
2971 		return -EINVAL;
2972 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2973 		return -EFAULT;
2974 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2975 		 info->device_name, gpio.state, gpio.smask,
2976 		 gpio.dir, gpio.dmask));
2977 
2978 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2979 	if (gpio.dmask) {
2980 		data = rd_reg32(info, IODR);
2981 		data |= gpio.dmask & gpio.dir;
2982 		data &= ~(gpio.dmask & ~gpio.dir);
2983 		wr_reg32(info, IODR, data);
2984 	}
2985 	if (gpio.smask) {
2986 		data = rd_reg32(info, IOVR);
2987 		data |= gpio.smask & gpio.state;
2988 		data &= ~(gpio.smask & ~gpio.state);
2989 		wr_reg32(info, IOVR, data);
2990 	}
2991 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2992 
2993 	return 0;
2994 }
2995 
2996 /*
2997  * get general purpose IO pin state and direction
2998  */
2999 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3000 {
3001 	struct gpio_desc gpio;
3002 	if (!info->gpio_present)
3003 		return -EINVAL;
3004 	gpio.state = rd_reg32(info, IOVR);
3005 	gpio.smask = 0xffffffff;
3006 	gpio.dir   = rd_reg32(info, IODR);
3007 	gpio.dmask = 0xffffffff;
3008 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3009 		return -EFAULT;
3010 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
3011 		 info->device_name, gpio.state, gpio.dir));
3012 	return 0;
3013 }
3014 
3015 /*
3016  * conditional wait facility
3017  */
3018 static void init_cond_wait(struct cond_wait *w, unsigned int data)
3019 {
3020 	init_waitqueue_head(&w->q);
3021 	init_waitqueue_entry(&w->wait, current);
3022 	w->data = data;
3023 }
3024 
3025 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
3026 {
3027 	set_current_state(TASK_INTERRUPTIBLE);
3028 	add_wait_queue(&w->q, &w->wait);
3029 	w->next = *head;
3030 	*head = w;
3031 }
3032 
3033 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
3034 {
3035 	struct cond_wait *w, *prev;
3036 	remove_wait_queue(&cw->q, &cw->wait);
3037 	set_current_state(TASK_RUNNING);
3038 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
3039 		if (w == cw) {
3040 			if (prev != NULL)
3041 				prev->next = w->next;
3042 			else
3043 				*head = w->next;
3044 			break;
3045 		}
3046 	}
3047 }
3048 
3049 static void flush_cond_wait(struct cond_wait **head)
3050 {
3051 	while (*head != NULL) {
3052 		wake_up_interruptible(&(*head)->q);
3053 		*head = (*head)->next;
3054 	}
3055 }
3056 
3057 /*
3058  * wait for general purpose I/O pin(s) to enter specified state
3059  *
3060  * user_gpio fields:
3061  * state - bit indicates target pin state
3062  * smask - set bit indicates watched pin
3063  *
3064  * The wait ends when at least one watched pin enters the specified
3065  * state. When 0 (no error) is returned, user_gpio->state is set to the
3066  * state of all GPIO pins when the wait ends.
3067  *
3068  * Note: Each pin may be a dedicated input, dedicated output, or
3069  * configurable input/output. The number and configuration of pins
3070  * varies with the specific adapter model. Only input pins (dedicated
3071  * or configured) can be monitored with this function.
3072  */
3073 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3074 {
3075  	unsigned long flags;
3076 	int rc = 0;
3077 	struct gpio_desc gpio;
3078 	struct cond_wait wait;
3079 	u32 state;
3080 
3081 	if (!info->gpio_present)
3082 		return -EINVAL;
3083 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
3084 		return -EFAULT;
3085 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3086 		 info->device_name, gpio.state, gpio.smask));
3087 	/* ignore output pins identified by set IODR bit */
3088 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3089 		return -EINVAL;
3090 	init_cond_wait(&wait, gpio.smask);
3091 
3092 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3093 	/* enable interrupts for watched pins */
3094 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3095 	/* get current pin states */
3096 	state = rd_reg32(info, IOVR);
3097 
3098 	if (gpio.smask & ~(state ^ gpio.state)) {
3099 		/* already in target state */
3100 		gpio.state = state;
3101 	} else {
3102 		/* wait for target state */
3103 		add_cond_wait(&info->gpio_wait_q, &wait);
3104 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3105 		schedule();
3106 		if (signal_pending(current))
3107 			rc = -ERESTARTSYS;
3108 		else
3109 			gpio.state = wait.data;
3110 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3111 		remove_cond_wait(&info->gpio_wait_q, &wait);
3112 	}
3113 
3114 	/* disable all GPIO interrupts if no waiting processes */
3115 	if (info->gpio_wait_q == NULL)
3116 		wr_reg32(info, IOER, 0);
3117 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3118 
3119 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3120 		rc = -EFAULT;
3121 	return rc;
3122 }
3123 
3124 static int modem_input_wait(struct slgt_info *info,int arg)
3125 {
3126  	unsigned long flags;
3127 	int rc;
3128 	struct mgsl_icount cprev, cnow;
3129 	DECLARE_WAITQUEUE(wait, current);
3130 
3131 	/* save current irq counts */
3132 	spin_lock_irqsave(&info->lock,flags);
3133 	cprev = info->icount;
3134 	add_wait_queue(&info->status_event_wait_q, &wait);
3135 	set_current_state(TASK_INTERRUPTIBLE);
3136 	spin_unlock_irqrestore(&info->lock,flags);
3137 
3138 	for(;;) {
3139 		schedule();
3140 		if (signal_pending(current)) {
3141 			rc = -ERESTARTSYS;
3142 			break;
3143 		}
3144 
3145 		/* get new irq counts */
3146 		spin_lock_irqsave(&info->lock,flags);
3147 		cnow = info->icount;
3148 		set_current_state(TASK_INTERRUPTIBLE);
3149 		spin_unlock_irqrestore(&info->lock,flags);
3150 
3151 		/* if no change, wait aborted for some reason */
3152 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3153 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3154 			rc = -EIO;
3155 			break;
3156 		}
3157 
3158 		/* check for change in caller specified modem input */
3159 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3160 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3161 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3162 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3163 			rc = 0;
3164 			break;
3165 		}
3166 
3167 		cprev = cnow;
3168 	}
3169 	remove_wait_queue(&info->status_event_wait_q, &wait);
3170 	set_current_state(TASK_RUNNING);
3171 	return rc;
3172 }
3173 
3174 /*
3175  *  return state of serial control and status signals
3176  */
3177 static int tiocmget(struct tty_struct *tty)
3178 {
3179 	struct slgt_info *info = tty->driver_data;
3180 	unsigned int result;
3181  	unsigned long flags;
3182 
3183 	spin_lock_irqsave(&info->lock,flags);
3184  	get_signals(info);
3185 	spin_unlock_irqrestore(&info->lock,flags);
3186 
3187 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3188 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3189 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3190 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3191 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3192 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3193 
3194 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3195 	return result;
3196 }
3197 
3198 /*
3199  * set modem control signals (DTR/RTS)
3200  *
3201  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3202  *		TIOCMSET = set/clear signal values
3203  * 	value	bit mask for command
3204  */
3205 static int tiocmset(struct tty_struct *tty,
3206 		    unsigned int set, unsigned int clear)
3207 {
3208 	struct slgt_info *info = tty->driver_data;
3209  	unsigned long flags;
3210 
3211 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3212 
3213 	if (set & TIOCM_RTS)
3214 		info->signals |= SerialSignal_RTS;
3215 	if (set & TIOCM_DTR)
3216 		info->signals |= SerialSignal_DTR;
3217 	if (clear & TIOCM_RTS)
3218 		info->signals &= ~SerialSignal_RTS;
3219 	if (clear & TIOCM_DTR)
3220 		info->signals &= ~SerialSignal_DTR;
3221 
3222 	spin_lock_irqsave(&info->lock,flags);
3223  	set_signals(info);
3224 	spin_unlock_irqrestore(&info->lock,flags);
3225 	return 0;
3226 }
3227 
3228 static int carrier_raised(struct tty_port *port)
3229 {
3230 	unsigned long flags;
3231 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3232 
3233 	spin_lock_irqsave(&info->lock,flags);
3234  	get_signals(info);
3235 	spin_unlock_irqrestore(&info->lock,flags);
3236 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3237 }
3238 
3239 static void dtr_rts(struct tty_port *port, int on)
3240 {
3241 	unsigned long flags;
3242 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3243 
3244 	spin_lock_irqsave(&info->lock,flags);
3245 	if (on)
3246 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3247 	else
3248 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3249  	set_signals(info);
3250 	spin_unlock_irqrestore(&info->lock,flags);
3251 }
3252 
3253 
3254 /*
3255  *  block current process until the device is ready to open
3256  */
3257 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3258 			   struct slgt_info *info)
3259 {
3260 	DECLARE_WAITQUEUE(wait, current);
3261 	int		retval;
3262 	bool		do_clocal = false;
3263 	unsigned long	flags;
3264 	int		cd;
3265 	struct tty_port *port = &info->port;
3266 
3267 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3268 
3269 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3270 		/* nonblock mode is set or port is not enabled */
3271 		tty_port_set_active(port, 1);
3272 		return 0;
3273 	}
3274 
3275 	if (C_CLOCAL(tty))
3276 		do_clocal = true;
3277 
3278 	/* Wait for carrier detect and the line to become
3279 	 * free (i.e., not in use by the callout).  While we are in
3280 	 * this loop, port->count is dropped by one, so that
3281 	 * close() knows when to free things.  We restore it upon
3282 	 * exit, either normal or abnormal.
3283 	 */
3284 
3285 	retval = 0;
3286 	add_wait_queue(&port->open_wait, &wait);
3287 
3288 	spin_lock_irqsave(&info->lock, flags);
3289 	port->count--;
3290 	spin_unlock_irqrestore(&info->lock, flags);
3291 	port->blocked_open++;
3292 
3293 	while (1) {
3294 		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
3295 			tty_port_raise_dtr_rts(port);
3296 
3297 		set_current_state(TASK_INTERRUPTIBLE);
3298 
3299 		if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)){
3300 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3301 					-EAGAIN : -ERESTARTSYS;
3302 			break;
3303 		}
3304 
3305 		cd = tty_port_carrier_raised(port);
3306 		if (do_clocal || cd)
3307 			break;
3308 
3309 		if (signal_pending(current)) {
3310 			retval = -ERESTARTSYS;
3311 			break;
3312 		}
3313 
3314 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3315 		tty_unlock(tty);
3316 		schedule();
3317 		tty_lock(tty);
3318 	}
3319 
3320 	set_current_state(TASK_RUNNING);
3321 	remove_wait_queue(&port->open_wait, &wait);
3322 
3323 	if (!tty_hung_up_p(filp))
3324 		port->count++;
3325 	port->blocked_open--;
3326 
3327 	if (!retval)
3328 		tty_port_set_active(port, 1);
3329 
3330 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3331 	return retval;
3332 }
3333 
3334 /*
3335  * allocate buffers used for calling line discipline receive_buf
3336  * directly in synchronous mode
3337  * note: add 5 bytes to max frame size to allow appending
3338  * 32-bit CRC and status byte when configured to do so
3339  */
3340 static int alloc_tmp_rbuf(struct slgt_info *info)
3341 {
3342 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3343 	if (info->tmp_rbuf == NULL)
3344 		return -ENOMEM;
3345 	/* unused flag buffer to satisfy receive_buf calling interface */
3346 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3347 	if (!info->flag_buf) {
3348 		kfree(info->tmp_rbuf);
3349 		info->tmp_rbuf = NULL;
3350 		return -ENOMEM;
3351 	}
3352 	return 0;
3353 }
3354 
3355 static void free_tmp_rbuf(struct slgt_info *info)
3356 {
3357 	kfree(info->tmp_rbuf);
3358 	info->tmp_rbuf = NULL;
3359 	kfree(info->flag_buf);
3360 	info->flag_buf = NULL;
3361 }
3362 
3363 /*
3364  * allocate DMA descriptor lists.
3365  */
3366 static int alloc_desc(struct slgt_info *info)
3367 {
3368 	unsigned int i;
3369 	unsigned int pbufs;
3370 
3371 	/* allocate memory to hold descriptor lists */
3372 	info->bufs = pci_zalloc_consistent(info->pdev, DESC_LIST_SIZE,
3373 					   &info->bufs_dma_addr);
3374 	if (info->bufs == NULL)
3375 		return -ENOMEM;
3376 
3377 	info->rbufs = (struct slgt_desc*)info->bufs;
3378 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3379 
3380 	pbufs = (unsigned int)info->bufs_dma_addr;
3381 
3382 	/*
3383 	 * Build circular lists of descriptors
3384 	 */
3385 
3386 	for (i=0; i < info->rbuf_count; i++) {
3387 		/* physical address of this descriptor */
3388 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3389 
3390 		/* physical address of next descriptor */
3391 		if (i == info->rbuf_count - 1)
3392 			info->rbufs[i].next = cpu_to_le32(pbufs);
3393 		else
3394 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3395 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3396 	}
3397 
3398 	for (i=0; i < info->tbuf_count; i++) {
3399 		/* physical address of this descriptor */
3400 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3401 
3402 		/* physical address of next descriptor */
3403 		if (i == info->tbuf_count - 1)
3404 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3405 		else
3406 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3407 	}
3408 
3409 	return 0;
3410 }
3411 
3412 static void free_desc(struct slgt_info *info)
3413 {
3414 	if (info->bufs != NULL) {
3415 		pci_free_consistent(info->pdev, DESC_LIST_SIZE, info->bufs, info->bufs_dma_addr);
3416 		info->bufs  = NULL;
3417 		info->rbufs = NULL;
3418 		info->tbufs = NULL;
3419 	}
3420 }
3421 
3422 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3423 {
3424 	int i;
3425 	for (i=0; i < count; i++) {
3426 		if ((bufs[i].buf = pci_alloc_consistent(info->pdev, DMABUFSIZE, &bufs[i].buf_dma_addr)) == NULL)
3427 			return -ENOMEM;
3428 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3429 	}
3430 	return 0;
3431 }
3432 
3433 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3434 {
3435 	int i;
3436 	for (i=0; i < count; i++) {
3437 		if (bufs[i].buf == NULL)
3438 			continue;
3439 		pci_free_consistent(info->pdev, DMABUFSIZE, bufs[i].buf, bufs[i].buf_dma_addr);
3440 		bufs[i].buf = NULL;
3441 	}
3442 }
3443 
3444 static int alloc_dma_bufs(struct slgt_info *info)
3445 {
3446 	info->rbuf_count = 32;
3447 	info->tbuf_count = 32;
3448 
3449 	if (alloc_desc(info) < 0 ||
3450 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3451 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3452 	    alloc_tmp_rbuf(info) < 0) {
3453 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3454 		return -ENOMEM;
3455 	}
3456 	reset_rbufs(info);
3457 	return 0;
3458 }
3459 
3460 static void free_dma_bufs(struct slgt_info *info)
3461 {
3462 	if (info->bufs) {
3463 		free_bufs(info, info->rbufs, info->rbuf_count);
3464 		free_bufs(info, info->tbufs, info->tbuf_count);
3465 		free_desc(info);
3466 	}
3467 	free_tmp_rbuf(info);
3468 }
3469 
3470 static int claim_resources(struct slgt_info *info)
3471 {
3472 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3473 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3474 			info->device_name, info->phys_reg_addr));
3475 		info->init_error = DiagStatus_AddressConflict;
3476 		goto errout;
3477 	}
3478 	else
3479 		info->reg_addr_requested = true;
3480 
3481 	info->reg_addr = ioremap_nocache(info->phys_reg_addr, SLGT_REG_SIZE);
3482 	if (!info->reg_addr) {
3483 		DBGERR(("%s can't map device registers, addr=%08X\n",
3484 			info->device_name, info->phys_reg_addr));
3485 		info->init_error = DiagStatus_CantAssignPciResources;
3486 		goto errout;
3487 	}
3488 	return 0;
3489 
3490 errout:
3491 	release_resources(info);
3492 	return -ENODEV;
3493 }
3494 
3495 static void release_resources(struct slgt_info *info)
3496 {
3497 	if (info->irq_requested) {
3498 		free_irq(info->irq_level, info);
3499 		info->irq_requested = false;
3500 	}
3501 
3502 	if (info->reg_addr_requested) {
3503 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3504 		info->reg_addr_requested = false;
3505 	}
3506 
3507 	if (info->reg_addr) {
3508 		iounmap(info->reg_addr);
3509 		info->reg_addr = NULL;
3510 	}
3511 }
3512 
3513 /* Add the specified device instance data structure to the
3514  * global linked list of devices and increment the device count.
3515  */
3516 static void add_device(struct slgt_info *info)
3517 {
3518 	char *devstr;
3519 
3520 	info->next_device = NULL;
3521 	info->line = slgt_device_count;
3522 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3523 
3524 	if (info->line < MAX_DEVICES) {
3525 		if (maxframe[info->line])
3526 			info->max_frame_size = maxframe[info->line];
3527 	}
3528 
3529 	slgt_device_count++;
3530 
3531 	if (!slgt_device_list)
3532 		slgt_device_list = info;
3533 	else {
3534 		struct slgt_info *current_dev = slgt_device_list;
3535 		while(current_dev->next_device)
3536 			current_dev = current_dev->next_device;
3537 		current_dev->next_device = info;
3538 	}
3539 
3540 	if (info->max_frame_size < 4096)
3541 		info->max_frame_size = 4096;
3542 	else if (info->max_frame_size > 65535)
3543 		info->max_frame_size = 65535;
3544 
3545 	switch(info->pdev->device) {
3546 	case SYNCLINK_GT_DEVICE_ID:
3547 		devstr = "GT";
3548 		break;
3549 	case SYNCLINK_GT2_DEVICE_ID:
3550 		devstr = "GT2";
3551 		break;
3552 	case SYNCLINK_GT4_DEVICE_ID:
3553 		devstr = "GT4";
3554 		break;
3555 	case SYNCLINK_AC_DEVICE_ID:
3556 		devstr = "AC";
3557 		info->params.mode = MGSL_MODE_ASYNC;
3558 		break;
3559 	default:
3560 		devstr = "(unknown model)";
3561 	}
3562 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3563 		devstr, info->device_name, info->phys_reg_addr,
3564 		info->irq_level, info->max_frame_size);
3565 
3566 #if SYNCLINK_GENERIC_HDLC
3567 	hdlcdev_init(info);
3568 #endif
3569 }
3570 
3571 static const struct tty_port_operations slgt_port_ops = {
3572 	.carrier_raised = carrier_raised,
3573 	.dtr_rts = dtr_rts,
3574 };
3575 
3576 /*
3577  *  allocate device instance structure, return NULL on failure
3578  */
3579 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3580 {
3581 	struct slgt_info *info;
3582 
3583 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3584 
3585 	if (!info) {
3586 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3587 			driver_name, adapter_num, port_num));
3588 	} else {
3589 		tty_port_init(&info->port);
3590 		info->port.ops = &slgt_port_ops;
3591 		info->magic = MGSL_MAGIC;
3592 		INIT_WORK(&info->task, bh_handler);
3593 		info->max_frame_size = 4096;
3594 		info->base_clock = 14745600;
3595 		info->rbuf_fill_level = DMABUFSIZE;
3596 		info->port.close_delay = 5*HZ/10;
3597 		info->port.closing_wait = 30*HZ;
3598 		init_waitqueue_head(&info->status_event_wait_q);
3599 		init_waitqueue_head(&info->event_wait_q);
3600 		spin_lock_init(&info->netlock);
3601 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3602 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3603 		info->adapter_num = adapter_num;
3604 		info->port_num = port_num;
3605 
3606 		setup_timer(&info->tx_timer, tx_timeout, (unsigned long)info);
3607 		setup_timer(&info->rx_timer, rx_timeout, (unsigned long)info);
3608 
3609 		/* Copy configuration info to device instance data */
3610 		info->pdev = pdev;
3611 		info->irq_level = pdev->irq;
3612 		info->phys_reg_addr = pci_resource_start(pdev,0);
3613 
3614 		info->bus_type = MGSL_BUS_TYPE_PCI;
3615 		info->irq_flags = IRQF_SHARED;
3616 
3617 		info->init_error = -1; /* assume error, set to 0 on successful init */
3618 	}
3619 
3620 	return info;
3621 }
3622 
3623 static void device_init(int adapter_num, struct pci_dev *pdev)
3624 {
3625 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3626 	int i;
3627 	int port_count = 1;
3628 
3629 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3630 		port_count = 2;
3631 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3632 		port_count = 4;
3633 
3634 	/* allocate device instances for all ports */
3635 	for (i=0; i < port_count; ++i) {
3636 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3637 		if (port_array[i] == NULL) {
3638 			for (--i; i >= 0; --i) {
3639 				tty_port_destroy(&port_array[i]->port);
3640 				kfree(port_array[i]);
3641 			}
3642 			return;
3643 		}
3644 	}
3645 
3646 	/* give copy of port_array to all ports and add to device list  */
3647 	for (i=0; i < port_count; ++i) {
3648 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3649 		add_device(port_array[i]);
3650 		port_array[i]->port_count = port_count;
3651 		spin_lock_init(&port_array[i]->lock);
3652 	}
3653 
3654 	/* Allocate and claim adapter resources */
3655 	if (!claim_resources(port_array[0])) {
3656 
3657 		alloc_dma_bufs(port_array[0]);
3658 
3659 		/* copy resource information from first port to others */
3660 		for (i = 1; i < port_count; ++i) {
3661 			port_array[i]->irq_level = port_array[0]->irq_level;
3662 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3663 			alloc_dma_bufs(port_array[i]);
3664 		}
3665 
3666 		if (request_irq(port_array[0]->irq_level,
3667 					slgt_interrupt,
3668 					port_array[0]->irq_flags,
3669 					port_array[0]->device_name,
3670 					port_array[0]) < 0) {
3671 			DBGERR(("%s request_irq failed IRQ=%d\n",
3672 				port_array[0]->device_name,
3673 				port_array[0]->irq_level));
3674 		} else {
3675 			port_array[0]->irq_requested = true;
3676 			adapter_test(port_array[0]);
3677 			for (i=1 ; i < port_count ; i++) {
3678 				port_array[i]->init_error = port_array[0]->init_error;
3679 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3680 			}
3681 		}
3682 	}
3683 
3684 	for (i = 0; i < port_count; ++i) {
3685 		struct slgt_info *info = port_array[i];
3686 		tty_port_register_device(&info->port, serial_driver, info->line,
3687 				&info->pdev->dev);
3688 	}
3689 }
3690 
3691 static int init_one(struct pci_dev *dev,
3692 			      const struct pci_device_id *ent)
3693 {
3694 	if (pci_enable_device(dev)) {
3695 		printk("error enabling pci device %p\n", dev);
3696 		return -EIO;
3697 	}
3698 	pci_set_master(dev);
3699 	device_init(slgt_device_count, dev);
3700 	return 0;
3701 }
3702 
3703 static void remove_one(struct pci_dev *dev)
3704 {
3705 }
3706 
3707 static const struct tty_operations ops = {
3708 	.open = open,
3709 	.close = close,
3710 	.write = write,
3711 	.put_char = put_char,
3712 	.flush_chars = flush_chars,
3713 	.write_room = write_room,
3714 	.chars_in_buffer = chars_in_buffer,
3715 	.flush_buffer = flush_buffer,
3716 	.ioctl = ioctl,
3717 	.compat_ioctl = slgt_compat_ioctl,
3718 	.throttle = throttle,
3719 	.unthrottle = unthrottle,
3720 	.send_xchar = send_xchar,
3721 	.break_ctl = set_break,
3722 	.wait_until_sent = wait_until_sent,
3723 	.set_termios = set_termios,
3724 	.stop = tx_hold,
3725 	.start = tx_release,
3726 	.hangup = hangup,
3727 	.tiocmget = tiocmget,
3728 	.tiocmset = tiocmset,
3729 	.get_icount = get_icount,
3730 	.proc_fops = &synclink_gt_proc_fops,
3731 };
3732 
3733 static void slgt_cleanup(void)
3734 {
3735 	int rc;
3736 	struct slgt_info *info;
3737 	struct slgt_info *tmp;
3738 
3739 	printk(KERN_INFO "unload %s\n", driver_name);
3740 
3741 	if (serial_driver) {
3742 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3743 			tty_unregister_device(serial_driver, info->line);
3744 		rc = tty_unregister_driver(serial_driver);
3745 		if (rc)
3746 			DBGERR(("tty_unregister_driver error=%d\n", rc));
3747 		put_tty_driver(serial_driver);
3748 	}
3749 
3750 	/* reset devices */
3751 	info = slgt_device_list;
3752 	while(info) {
3753 		reset_port(info);
3754 		info = info->next_device;
3755 	}
3756 
3757 	/* release devices */
3758 	info = slgt_device_list;
3759 	while(info) {
3760 #if SYNCLINK_GENERIC_HDLC
3761 		hdlcdev_exit(info);
3762 #endif
3763 		free_dma_bufs(info);
3764 		free_tmp_rbuf(info);
3765 		if (info->port_num == 0)
3766 			release_resources(info);
3767 		tmp = info;
3768 		info = info->next_device;
3769 		tty_port_destroy(&tmp->port);
3770 		kfree(tmp);
3771 	}
3772 
3773 	if (pci_registered)
3774 		pci_unregister_driver(&pci_driver);
3775 }
3776 
3777 /*
3778  *  Driver initialization entry point.
3779  */
3780 static int __init slgt_init(void)
3781 {
3782 	int rc;
3783 
3784 	printk(KERN_INFO "%s\n", driver_name);
3785 
3786 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3787 	if (!serial_driver) {
3788 		printk("%s can't allocate tty driver\n", driver_name);
3789 		return -ENOMEM;
3790 	}
3791 
3792 	/* Initialize the tty_driver structure */
3793 
3794 	serial_driver->driver_name = slgt_driver_name;
3795 	serial_driver->name = tty_dev_prefix;
3796 	serial_driver->major = ttymajor;
3797 	serial_driver->minor_start = 64;
3798 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3799 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3800 	serial_driver->init_termios = tty_std_termios;
3801 	serial_driver->init_termios.c_cflag =
3802 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3803 	serial_driver->init_termios.c_ispeed = 9600;
3804 	serial_driver->init_termios.c_ospeed = 9600;
3805 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3806 	tty_set_operations(serial_driver, &ops);
3807 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3808 		DBGERR(("%s can't register serial driver\n", driver_name));
3809 		put_tty_driver(serial_driver);
3810 		serial_driver = NULL;
3811 		goto error;
3812 	}
3813 
3814 	printk(KERN_INFO "%s, tty major#%d\n",
3815 	       driver_name, serial_driver->major);
3816 
3817 	slgt_device_count = 0;
3818 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3819 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3820 		goto error;
3821 	}
3822 	pci_registered = true;
3823 
3824 	if (!slgt_device_list)
3825 		printk("%s no devices found\n",driver_name);
3826 
3827 	return 0;
3828 
3829 error:
3830 	slgt_cleanup();
3831 	return rc;
3832 }
3833 
3834 static void __exit slgt_exit(void)
3835 {
3836 	slgt_cleanup();
3837 }
3838 
3839 module_init(slgt_init);
3840 module_exit(slgt_exit);
3841 
3842 /*
3843  * register access routines
3844  */
3845 
3846 #define CALC_REGADDR() \
3847 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3848 	if (addr >= 0x80) \
3849 		reg_addr += (info->port_num) * 32; \
3850 	else if (addr >= 0x40)	\
3851 		reg_addr += (info->port_num) * 16;
3852 
3853 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3854 {
3855 	CALC_REGADDR();
3856 	return readb((void __iomem *)reg_addr);
3857 }
3858 
3859 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3860 {
3861 	CALC_REGADDR();
3862 	writeb(value, (void __iomem *)reg_addr);
3863 }
3864 
3865 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3866 {
3867 	CALC_REGADDR();
3868 	return readw((void __iomem *)reg_addr);
3869 }
3870 
3871 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3872 {
3873 	CALC_REGADDR();
3874 	writew(value, (void __iomem *)reg_addr);
3875 }
3876 
3877 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3878 {
3879 	CALC_REGADDR();
3880 	return readl((void __iomem *)reg_addr);
3881 }
3882 
3883 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3884 {
3885 	CALC_REGADDR();
3886 	writel(value, (void __iomem *)reg_addr);
3887 }
3888 
3889 static void rdma_reset(struct slgt_info *info)
3890 {
3891 	unsigned int i;
3892 
3893 	/* set reset bit */
3894 	wr_reg32(info, RDCSR, BIT1);
3895 
3896 	/* wait for enable bit cleared */
3897 	for(i=0 ; i < 1000 ; i++)
3898 		if (!(rd_reg32(info, RDCSR) & BIT0))
3899 			break;
3900 }
3901 
3902 static void tdma_reset(struct slgt_info *info)
3903 {
3904 	unsigned int i;
3905 
3906 	/* set reset bit */
3907 	wr_reg32(info, TDCSR, BIT1);
3908 
3909 	/* wait for enable bit cleared */
3910 	for(i=0 ; i < 1000 ; i++)
3911 		if (!(rd_reg32(info, TDCSR) & BIT0))
3912 			break;
3913 }
3914 
3915 /*
3916  * enable internal loopback
3917  * TxCLK and RxCLK are generated from BRG
3918  * and TxD is looped back to RxD internally.
3919  */
3920 static void enable_loopback(struct slgt_info *info)
3921 {
3922 	/* SCR (serial control) BIT2=loopback enable */
3923 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3924 
3925 	if (info->params.mode != MGSL_MODE_ASYNC) {
3926 		/* CCR (clock control)
3927 		 * 07..05  tx clock source (010 = BRG)
3928 		 * 04..02  rx clock source (010 = BRG)
3929 		 * 01      auxclk enable   (0 = disable)
3930 		 * 00      BRG enable      (1 = enable)
3931 		 *
3932 		 * 0100 1001
3933 		 */
3934 		wr_reg8(info, CCR, 0x49);
3935 
3936 		/* set speed if available, otherwise use default */
3937 		if (info->params.clock_speed)
3938 			set_rate(info, info->params.clock_speed);
3939 		else
3940 			set_rate(info, 3686400);
3941 	}
3942 }
3943 
3944 /*
3945  *  set baud rate generator to specified rate
3946  */
3947 static void set_rate(struct slgt_info *info, u32 rate)
3948 {
3949 	unsigned int div;
3950 	unsigned int osc = info->base_clock;
3951 
3952 	/* div = osc/rate - 1
3953 	 *
3954 	 * Round div up if osc/rate is not integer to
3955 	 * force to next slowest rate.
3956 	 */
3957 
3958 	if (rate) {
3959 		div = osc/rate;
3960 		if (!(osc % rate) && div)
3961 			div--;
3962 		wr_reg16(info, BDR, (unsigned short)div);
3963 	}
3964 }
3965 
3966 static void rx_stop(struct slgt_info *info)
3967 {
3968 	unsigned short val;
3969 
3970 	/* disable and reset receiver */
3971 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3972 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3973 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3974 
3975 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3976 
3977 	/* clear pending rx interrupts */
3978 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3979 
3980 	rdma_reset(info);
3981 
3982 	info->rx_enabled = false;
3983 	info->rx_restart = false;
3984 }
3985 
3986 static void rx_start(struct slgt_info *info)
3987 {
3988 	unsigned short val;
3989 
3990 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3991 
3992 	/* clear pending rx overrun IRQ */
3993 	wr_reg16(info, SSR, IRQ_RXOVER);
3994 
3995 	/* reset and disable receiver */
3996 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3997 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3998 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3999 
4000 	rdma_reset(info);
4001 	reset_rbufs(info);
4002 
4003 	if (info->rx_pio) {
4004 		/* rx request when rx FIFO not empty */
4005 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
4006 		slgt_irq_on(info, IRQ_RXDATA);
4007 		if (info->params.mode == MGSL_MODE_ASYNC) {
4008 			/* enable saving of rx status */
4009 			wr_reg32(info, RDCSR, BIT6);
4010 		}
4011 	} else {
4012 		/* rx request when rx FIFO half full */
4013 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
4014 		/* set 1st descriptor address */
4015 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
4016 
4017 		if (info->params.mode != MGSL_MODE_ASYNC) {
4018 			/* enable rx DMA and DMA interrupt */
4019 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
4020 		} else {
4021 			/* enable saving of rx status, rx DMA and DMA interrupt */
4022 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
4023 		}
4024 	}
4025 
4026 	slgt_irq_on(info, IRQ_RXOVER);
4027 
4028 	/* enable receiver */
4029 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
4030 
4031 	info->rx_restart = false;
4032 	info->rx_enabled = true;
4033 }
4034 
4035 static void tx_start(struct slgt_info *info)
4036 {
4037 	if (!info->tx_enabled) {
4038 		wr_reg16(info, TCR,
4039 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
4040 		info->tx_enabled = true;
4041 	}
4042 
4043 	if (desc_count(info->tbufs[info->tbuf_start])) {
4044 		info->drop_rts_on_tx_done = false;
4045 
4046 		if (info->params.mode != MGSL_MODE_ASYNC) {
4047 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
4048 				get_signals(info);
4049 				if (!(info->signals & SerialSignal_RTS)) {
4050 					info->signals |= SerialSignal_RTS;
4051 					set_signals(info);
4052 					info->drop_rts_on_tx_done = true;
4053 				}
4054 			}
4055 
4056 			slgt_irq_off(info, IRQ_TXDATA);
4057 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
4058 			/* clear tx idle and underrun status bits */
4059 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4060 		} else {
4061 			slgt_irq_off(info, IRQ_TXDATA);
4062 			slgt_irq_on(info, IRQ_TXIDLE);
4063 			/* clear tx idle status bit */
4064 			wr_reg16(info, SSR, IRQ_TXIDLE);
4065 		}
4066 		/* set 1st descriptor address and start DMA */
4067 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
4068 		wr_reg32(info, TDCSR, BIT2 + BIT0);
4069 		info->tx_active = true;
4070 	}
4071 }
4072 
4073 static void tx_stop(struct slgt_info *info)
4074 {
4075 	unsigned short val;
4076 
4077 	del_timer(&info->tx_timer);
4078 
4079 	tdma_reset(info);
4080 
4081 	/* reset and disable transmitter */
4082 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
4083 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
4084 
4085 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
4086 
4087 	/* clear tx idle and underrun status bit */
4088 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4089 
4090 	reset_tbufs(info);
4091 
4092 	info->tx_enabled = false;
4093 	info->tx_active = false;
4094 }
4095 
4096 static void reset_port(struct slgt_info *info)
4097 {
4098 	if (!info->reg_addr)
4099 		return;
4100 
4101 	tx_stop(info);
4102 	rx_stop(info);
4103 
4104 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4105 	set_signals(info);
4106 
4107 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4108 }
4109 
4110 static void reset_adapter(struct slgt_info *info)
4111 {
4112 	int i;
4113 	for (i=0; i < info->port_count; ++i) {
4114 		if (info->port_array[i])
4115 			reset_port(info->port_array[i]);
4116 	}
4117 }
4118 
4119 static void async_mode(struct slgt_info *info)
4120 {
4121   	unsigned short val;
4122 
4123 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4124 	tx_stop(info);
4125 	rx_stop(info);
4126 
4127 	/* TCR (tx control)
4128 	 *
4129 	 * 15..13  mode, 010=async
4130 	 * 12..10  encoding, 000=NRZ
4131 	 * 09      parity enable
4132 	 * 08      1=odd parity, 0=even parity
4133 	 * 07      1=RTS driver control
4134 	 * 06      1=break enable
4135 	 * 05..04  character length
4136 	 *         00=5 bits
4137 	 *         01=6 bits
4138 	 *         10=7 bits
4139 	 *         11=8 bits
4140 	 * 03      0=1 stop bit, 1=2 stop bits
4141 	 * 02      reset
4142 	 * 01      enable
4143 	 * 00      auto-CTS enable
4144 	 */
4145 	val = 0x4000;
4146 
4147 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4148 		val |= BIT7;
4149 
4150 	if (info->params.parity != ASYNC_PARITY_NONE) {
4151 		val |= BIT9;
4152 		if (info->params.parity == ASYNC_PARITY_ODD)
4153 			val |= BIT8;
4154 	}
4155 
4156 	switch (info->params.data_bits)
4157 	{
4158 	case 6: val |= BIT4; break;
4159 	case 7: val |= BIT5; break;
4160 	case 8: val |= BIT5 + BIT4; break;
4161 	}
4162 
4163 	if (info->params.stop_bits != 1)
4164 		val |= BIT3;
4165 
4166 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4167 		val |= BIT0;
4168 
4169 	wr_reg16(info, TCR, val);
4170 
4171 	/* RCR (rx control)
4172 	 *
4173 	 * 15..13  mode, 010=async
4174 	 * 12..10  encoding, 000=NRZ
4175 	 * 09      parity enable
4176 	 * 08      1=odd parity, 0=even parity
4177 	 * 07..06  reserved, must be 0
4178 	 * 05..04  character length
4179 	 *         00=5 bits
4180 	 *         01=6 bits
4181 	 *         10=7 bits
4182 	 *         11=8 bits
4183 	 * 03      reserved, must be zero
4184 	 * 02      reset
4185 	 * 01      enable
4186 	 * 00      auto-DCD enable
4187 	 */
4188 	val = 0x4000;
4189 
4190 	if (info->params.parity != ASYNC_PARITY_NONE) {
4191 		val |= BIT9;
4192 		if (info->params.parity == ASYNC_PARITY_ODD)
4193 			val |= BIT8;
4194 	}
4195 
4196 	switch (info->params.data_bits)
4197 	{
4198 	case 6: val |= BIT4; break;
4199 	case 7: val |= BIT5; break;
4200 	case 8: val |= BIT5 + BIT4; break;
4201 	}
4202 
4203 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4204 		val |= BIT0;
4205 
4206 	wr_reg16(info, RCR, val);
4207 
4208 	/* CCR (clock control)
4209 	 *
4210 	 * 07..05  011 = tx clock source is BRG/16
4211 	 * 04..02  010 = rx clock source is BRG
4212 	 * 01      0 = auxclk disabled
4213 	 * 00      1 = BRG enabled
4214 	 *
4215 	 * 0110 1001
4216 	 */
4217 	wr_reg8(info, CCR, 0x69);
4218 
4219 	msc_set_vcr(info);
4220 
4221 	/* SCR (serial control)
4222 	 *
4223 	 * 15  1=tx req on FIFO half empty
4224 	 * 14  1=rx req on FIFO half full
4225 	 * 13  tx data  IRQ enable
4226 	 * 12  tx idle  IRQ enable
4227 	 * 11  rx break on IRQ enable
4228 	 * 10  rx data  IRQ enable
4229 	 * 09  rx break off IRQ enable
4230 	 * 08  overrun  IRQ enable
4231 	 * 07  DSR      IRQ enable
4232 	 * 06  CTS      IRQ enable
4233 	 * 05  DCD      IRQ enable
4234 	 * 04  RI       IRQ enable
4235 	 * 03  0=16x sampling, 1=8x sampling
4236 	 * 02  1=txd->rxd internal loopback enable
4237 	 * 01  reserved, must be zero
4238 	 * 00  1=master IRQ enable
4239 	 */
4240 	val = BIT15 + BIT14 + BIT0;
4241 	/* JCR[8] : 1 = x8 async mode feature available */
4242 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4243 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4244 	     (info->base_clock % (info->params.data_rate * 16)))) {
4245 		/* use 8x sampling */
4246 		val |= BIT3;
4247 		set_rate(info, info->params.data_rate * 8);
4248 	} else {
4249 		/* use 16x sampling */
4250 		set_rate(info, info->params.data_rate * 16);
4251 	}
4252 	wr_reg16(info, SCR, val);
4253 
4254 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4255 
4256 	if (info->params.loopback)
4257 		enable_loopback(info);
4258 }
4259 
4260 static void sync_mode(struct slgt_info *info)
4261 {
4262 	unsigned short val;
4263 
4264 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4265 	tx_stop(info);
4266 	rx_stop(info);
4267 
4268 	/* TCR (tx control)
4269 	 *
4270 	 * 15..13  mode
4271 	 *         000=HDLC/SDLC
4272 	 *         001=raw bit synchronous
4273 	 *         010=asynchronous/isochronous
4274 	 *         011=monosync byte synchronous
4275 	 *         100=bisync byte synchronous
4276 	 *         101=xsync byte synchronous
4277 	 * 12..10  encoding
4278 	 * 09      CRC enable
4279 	 * 08      CRC32
4280 	 * 07      1=RTS driver control
4281 	 * 06      preamble enable
4282 	 * 05..04  preamble length
4283 	 * 03      share open/close flag
4284 	 * 02      reset
4285 	 * 01      enable
4286 	 * 00      auto-CTS enable
4287 	 */
4288 	val = BIT2;
4289 
4290 	switch(info->params.mode) {
4291 	case MGSL_MODE_XSYNC:
4292 		val |= BIT15 + BIT13;
4293 		break;
4294 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4295 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4296 	case MGSL_MODE_RAW:      val |= BIT13; break;
4297 	}
4298 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4299 		val |= BIT7;
4300 
4301 	switch(info->params.encoding)
4302 	{
4303 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4304 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4305 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4306 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4307 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4308 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4309 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4310 	}
4311 
4312 	switch (info->params.crc_type & HDLC_CRC_MASK)
4313 	{
4314 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4315 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4316 	}
4317 
4318 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4319 		val |= BIT6;
4320 
4321 	switch (info->params.preamble_length)
4322 	{
4323 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4324 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4325 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4326 	}
4327 
4328 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4329 		val |= BIT0;
4330 
4331 	wr_reg16(info, TCR, val);
4332 
4333 	/* TPR (transmit preamble) */
4334 
4335 	switch (info->params.preamble)
4336 	{
4337 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4338 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4339 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4340 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4341 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4342 	default:                          val = 0x7e; break;
4343 	}
4344 	wr_reg8(info, TPR, (unsigned char)val);
4345 
4346 	/* RCR (rx control)
4347 	 *
4348 	 * 15..13  mode
4349 	 *         000=HDLC/SDLC
4350 	 *         001=raw bit synchronous
4351 	 *         010=asynchronous/isochronous
4352 	 *         011=monosync byte synchronous
4353 	 *         100=bisync byte synchronous
4354 	 *         101=xsync byte synchronous
4355 	 * 12..10  encoding
4356 	 * 09      CRC enable
4357 	 * 08      CRC32
4358 	 * 07..03  reserved, must be 0
4359 	 * 02      reset
4360 	 * 01      enable
4361 	 * 00      auto-DCD enable
4362 	 */
4363 	val = 0;
4364 
4365 	switch(info->params.mode) {
4366 	case MGSL_MODE_XSYNC:
4367 		val |= BIT15 + BIT13;
4368 		break;
4369 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4370 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4371 	case MGSL_MODE_RAW:      val |= BIT13; break;
4372 	}
4373 
4374 	switch(info->params.encoding)
4375 	{
4376 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4377 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4378 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4379 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4380 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4381 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4382 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4383 	}
4384 
4385 	switch (info->params.crc_type & HDLC_CRC_MASK)
4386 	{
4387 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4388 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4389 	}
4390 
4391 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4392 		val |= BIT0;
4393 
4394 	wr_reg16(info, RCR, val);
4395 
4396 	/* CCR (clock control)
4397 	 *
4398 	 * 07..05  tx clock source
4399 	 * 04..02  rx clock source
4400 	 * 01      auxclk enable
4401 	 * 00      BRG enable
4402 	 */
4403 	val = 0;
4404 
4405 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4406 	{
4407 		// when RxC source is DPLL, BRG generates 16X DPLL
4408 		// reference clock, so take TxC from BRG/16 to get
4409 		// transmit clock at actual data rate
4410 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4411 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4412 		else
4413 			val |= BIT6;	/* 010, txclk = BRG */
4414 	}
4415 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4416 		val |= BIT7;	/* 100, txclk = DPLL Input */
4417 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4418 		val |= BIT5;	/* 001, txclk = RXC Input */
4419 
4420 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4421 		val |= BIT3;	/* 010, rxclk = BRG */
4422 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4423 		val |= BIT4;	/* 100, rxclk = DPLL */
4424 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4425 		val |= BIT2;	/* 001, rxclk = TXC Input */
4426 
4427 	if (info->params.clock_speed)
4428 		val |= BIT1 + BIT0;
4429 
4430 	wr_reg8(info, CCR, (unsigned char)val);
4431 
4432 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4433 	{
4434 		// program DPLL mode
4435 		switch(info->params.encoding)
4436 		{
4437 		case HDLC_ENCODING_BIPHASE_MARK:
4438 		case HDLC_ENCODING_BIPHASE_SPACE:
4439 			val = BIT7; break;
4440 		case HDLC_ENCODING_BIPHASE_LEVEL:
4441 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4442 			val = BIT7 + BIT6; break;
4443 		default: val = BIT6;	// NRZ encodings
4444 		}
4445 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4446 
4447 		// DPLL requires a 16X reference clock from BRG
4448 		set_rate(info, info->params.clock_speed * 16);
4449 	}
4450 	else
4451 		set_rate(info, info->params.clock_speed);
4452 
4453 	tx_set_idle(info);
4454 
4455 	msc_set_vcr(info);
4456 
4457 	/* SCR (serial control)
4458 	 *
4459 	 * 15  1=tx req on FIFO half empty
4460 	 * 14  1=rx req on FIFO half full
4461 	 * 13  tx data  IRQ enable
4462 	 * 12  tx idle  IRQ enable
4463 	 * 11  underrun IRQ enable
4464 	 * 10  rx data  IRQ enable
4465 	 * 09  rx idle  IRQ enable
4466 	 * 08  overrun  IRQ enable
4467 	 * 07  DSR      IRQ enable
4468 	 * 06  CTS      IRQ enable
4469 	 * 05  DCD      IRQ enable
4470 	 * 04  RI       IRQ enable
4471 	 * 03  reserved, must be zero
4472 	 * 02  1=txd->rxd internal loopback enable
4473 	 * 01  reserved, must be zero
4474 	 * 00  1=master IRQ enable
4475 	 */
4476 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4477 
4478 	if (info->params.loopback)
4479 		enable_loopback(info);
4480 }
4481 
4482 /*
4483  *  set transmit idle mode
4484  */
4485 static void tx_set_idle(struct slgt_info *info)
4486 {
4487 	unsigned char val;
4488 	unsigned short tcr;
4489 
4490 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4491 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4492 	 */
4493 	tcr = rd_reg16(info, TCR);
4494 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4495 		/* disable preamble, set idle size to 16 bits */
4496 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4497 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4498 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4499 	} else if (!(tcr & BIT6)) {
4500 		/* preamble is disabled, set idle size to 8 bits */
4501 		tcr &= ~(BIT5 + BIT4);
4502 	}
4503 	wr_reg16(info, TCR, tcr);
4504 
4505 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4506 		/* LSB of custom tx idle specified in tx idle register */
4507 		val = (unsigned char)(info->idle_mode & 0xff);
4508 	} else {
4509 		/* standard 8 bit idle patterns */
4510 		switch(info->idle_mode)
4511 		{
4512 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4513 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4514 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4515 		case HDLC_TXIDLE_ZEROS:
4516 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4517 		default:                         val = 0xff;
4518 		}
4519 	}
4520 
4521 	wr_reg8(info, TIR, val);
4522 }
4523 
4524 /*
4525  * get state of V24 status (input) signals
4526  */
4527 static void get_signals(struct slgt_info *info)
4528 {
4529 	unsigned short status = rd_reg16(info, SSR);
4530 
4531 	/* clear all serial signals except RTS and DTR */
4532 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4533 
4534 	if (status & BIT3)
4535 		info->signals |= SerialSignal_DSR;
4536 	if (status & BIT2)
4537 		info->signals |= SerialSignal_CTS;
4538 	if (status & BIT1)
4539 		info->signals |= SerialSignal_DCD;
4540 	if (status & BIT0)
4541 		info->signals |= SerialSignal_RI;
4542 }
4543 
4544 /*
4545  * set V.24 Control Register based on current configuration
4546  */
4547 static void msc_set_vcr(struct slgt_info *info)
4548 {
4549 	unsigned char val = 0;
4550 
4551 	/* VCR (V.24 control)
4552 	 *
4553 	 * 07..04  serial IF select
4554 	 * 03      DTR
4555 	 * 02      RTS
4556 	 * 01      LL
4557 	 * 00      RL
4558 	 */
4559 
4560 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4561 	{
4562 	case MGSL_INTERFACE_RS232:
4563 		val |= BIT5; /* 0010 */
4564 		break;
4565 	case MGSL_INTERFACE_V35:
4566 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4567 		break;
4568 	case MGSL_INTERFACE_RS422:
4569 		val |= BIT6; /* 0100 */
4570 		break;
4571 	}
4572 
4573 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4574 		val |= BIT4;
4575 	if (info->signals & SerialSignal_DTR)
4576 		val |= BIT3;
4577 	if (info->signals & SerialSignal_RTS)
4578 		val |= BIT2;
4579 	if (info->if_mode & MGSL_INTERFACE_LL)
4580 		val |= BIT1;
4581 	if (info->if_mode & MGSL_INTERFACE_RL)
4582 		val |= BIT0;
4583 	wr_reg8(info, VCR, val);
4584 }
4585 
4586 /*
4587  * set state of V24 control (output) signals
4588  */
4589 static void set_signals(struct slgt_info *info)
4590 {
4591 	unsigned char val = rd_reg8(info, VCR);
4592 	if (info->signals & SerialSignal_DTR)
4593 		val |= BIT3;
4594 	else
4595 		val &= ~BIT3;
4596 	if (info->signals & SerialSignal_RTS)
4597 		val |= BIT2;
4598 	else
4599 		val &= ~BIT2;
4600 	wr_reg8(info, VCR, val);
4601 }
4602 
4603 /*
4604  * free range of receive DMA buffers (i to last)
4605  */
4606 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4607 {
4608 	int done = 0;
4609 
4610 	while(!done) {
4611 		/* reset current buffer for reuse */
4612 		info->rbufs[i].status = 0;
4613 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4614 		if (i == last)
4615 			done = 1;
4616 		if (++i == info->rbuf_count)
4617 			i = 0;
4618 	}
4619 	info->rbuf_current = i;
4620 }
4621 
4622 /*
4623  * mark all receive DMA buffers as free
4624  */
4625 static void reset_rbufs(struct slgt_info *info)
4626 {
4627 	free_rbufs(info, 0, info->rbuf_count - 1);
4628 	info->rbuf_fill_index = 0;
4629 	info->rbuf_fill_count = 0;
4630 }
4631 
4632 /*
4633  * pass receive HDLC frame to upper layer
4634  *
4635  * return true if frame available, otherwise false
4636  */
4637 static bool rx_get_frame(struct slgt_info *info)
4638 {
4639 	unsigned int start, end;
4640 	unsigned short status;
4641 	unsigned int framesize = 0;
4642 	unsigned long flags;
4643 	struct tty_struct *tty = info->port.tty;
4644 	unsigned char addr_field = 0xff;
4645 	unsigned int crc_size = 0;
4646 
4647 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4648 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4649 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4650 	}
4651 
4652 check_again:
4653 
4654 	framesize = 0;
4655 	addr_field = 0xff;
4656 	start = end = info->rbuf_current;
4657 
4658 	for (;;) {
4659 		if (!desc_complete(info->rbufs[end]))
4660 			goto cleanup;
4661 
4662 		if (framesize == 0 && info->params.addr_filter != 0xff)
4663 			addr_field = info->rbufs[end].buf[0];
4664 
4665 		framesize += desc_count(info->rbufs[end]);
4666 
4667 		if (desc_eof(info->rbufs[end]))
4668 			break;
4669 
4670 		if (++end == info->rbuf_count)
4671 			end = 0;
4672 
4673 		if (end == info->rbuf_current) {
4674 			if (info->rx_enabled){
4675 				spin_lock_irqsave(&info->lock,flags);
4676 				rx_start(info);
4677 				spin_unlock_irqrestore(&info->lock,flags);
4678 			}
4679 			goto cleanup;
4680 		}
4681 	}
4682 
4683 	/* status
4684 	 *
4685 	 * 15      buffer complete
4686 	 * 14..06  reserved
4687 	 * 05..04  residue
4688 	 * 02      eof (end of frame)
4689 	 * 01      CRC error
4690 	 * 00      abort
4691 	 */
4692 	status = desc_status(info->rbufs[end]);
4693 
4694 	/* ignore CRC bit if not using CRC (bit is undefined) */
4695 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4696 		status &= ~BIT1;
4697 
4698 	if (framesize == 0 ||
4699 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4700 		free_rbufs(info, start, end);
4701 		goto check_again;
4702 	}
4703 
4704 	if (framesize < (2 + crc_size) || status & BIT0) {
4705 		info->icount.rxshort++;
4706 		framesize = 0;
4707 	} else if (status & BIT1) {
4708 		info->icount.rxcrc++;
4709 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4710 			framesize = 0;
4711 	}
4712 
4713 #if SYNCLINK_GENERIC_HDLC
4714 	if (framesize == 0) {
4715 		info->netdev->stats.rx_errors++;
4716 		info->netdev->stats.rx_frame_errors++;
4717 	}
4718 #endif
4719 
4720 	DBGBH(("%s rx frame status=%04X size=%d\n",
4721 		info->device_name, status, framesize));
4722 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4723 
4724 	if (framesize) {
4725 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4726 			framesize -= crc_size;
4727 			crc_size = 0;
4728 		}
4729 
4730 		if (framesize > info->max_frame_size + crc_size)
4731 			info->icount.rxlong++;
4732 		else {
4733 			/* copy dma buffer(s) to contiguous temp buffer */
4734 			int copy_count = framesize;
4735 			int i = start;
4736 			unsigned char *p = info->tmp_rbuf;
4737 			info->tmp_rbuf_count = framesize;
4738 
4739 			info->icount.rxok++;
4740 
4741 			while(copy_count) {
4742 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4743 				memcpy(p, info->rbufs[i].buf, partial_count);
4744 				p += partial_count;
4745 				copy_count -= partial_count;
4746 				if (++i == info->rbuf_count)
4747 					i = 0;
4748 			}
4749 
4750 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4751 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4752 				framesize++;
4753 			}
4754 
4755 #if SYNCLINK_GENERIC_HDLC
4756 			if (info->netcount)
4757 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4758 			else
4759 #endif
4760 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4761 		}
4762 	}
4763 	free_rbufs(info, start, end);
4764 	return true;
4765 
4766 cleanup:
4767 	return false;
4768 }
4769 
4770 /*
4771  * pass receive buffer (RAW synchronous mode) to tty layer
4772  * return true if buffer available, otherwise false
4773  */
4774 static bool rx_get_buf(struct slgt_info *info)
4775 {
4776 	unsigned int i = info->rbuf_current;
4777 	unsigned int count;
4778 
4779 	if (!desc_complete(info->rbufs[i]))
4780 		return false;
4781 	count = desc_count(info->rbufs[i]);
4782 	switch(info->params.mode) {
4783 	case MGSL_MODE_MONOSYNC:
4784 	case MGSL_MODE_BISYNC:
4785 	case MGSL_MODE_XSYNC:
4786 		/* ignore residue in byte synchronous modes */
4787 		if (desc_residue(info->rbufs[i]))
4788 			count--;
4789 		break;
4790 	}
4791 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4792 	DBGINFO(("rx_get_buf size=%d\n", count));
4793 	if (count)
4794 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4795 				  info->flag_buf, count);
4796 	free_rbufs(info, i, i);
4797 	return true;
4798 }
4799 
4800 static void reset_tbufs(struct slgt_info *info)
4801 {
4802 	unsigned int i;
4803 	info->tbuf_current = 0;
4804 	for (i=0 ; i < info->tbuf_count ; i++) {
4805 		info->tbufs[i].status = 0;
4806 		info->tbufs[i].count  = 0;
4807 	}
4808 }
4809 
4810 /*
4811  * return number of free transmit DMA buffers
4812  */
4813 static unsigned int free_tbuf_count(struct slgt_info *info)
4814 {
4815 	unsigned int count = 0;
4816 	unsigned int i = info->tbuf_current;
4817 
4818 	do
4819 	{
4820 		if (desc_count(info->tbufs[i]))
4821 			break; /* buffer in use */
4822 		++count;
4823 		if (++i == info->tbuf_count)
4824 			i=0;
4825 	} while (i != info->tbuf_current);
4826 
4827 	/* if tx DMA active, last zero count buffer is in use */
4828 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4829 		--count;
4830 
4831 	return count;
4832 }
4833 
4834 /*
4835  * return number of bytes in unsent transmit DMA buffers
4836  * and the serial controller tx FIFO
4837  */
4838 static unsigned int tbuf_bytes(struct slgt_info *info)
4839 {
4840 	unsigned int total_count = 0;
4841 	unsigned int i = info->tbuf_current;
4842 	unsigned int reg_value;
4843 	unsigned int count;
4844 	unsigned int active_buf_count = 0;
4845 
4846 	/*
4847 	 * Add descriptor counts for all tx DMA buffers.
4848 	 * If count is zero (cleared by DMA controller after read),
4849 	 * the buffer is complete or is actively being read from.
4850 	 *
4851 	 * Record buf_count of last buffer with zero count starting
4852 	 * from current ring position. buf_count is mirror
4853 	 * copy of count and is not cleared by serial controller.
4854 	 * If DMA controller is active, that buffer is actively
4855 	 * being read so add to total.
4856 	 */
4857 	do {
4858 		count = desc_count(info->tbufs[i]);
4859 		if (count)
4860 			total_count += count;
4861 		else if (!total_count)
4862 			active_buf_count = info->tbufs[i].buf_count;
4863 		if (++i == info->tbuf_count)
4864 			i = 0;
4865 	} while (i != info->tbuf_current);
4866 
4867 	/* read tx DMA status register */
4868 	reg_value = rd_reg32(info, TDCSR);
4869 
4870 	/* if tx DMA active, last zero count buffer is in use */
4871 	if (reg_value & BIT0)
4872 		total_count += active_buf_count;
4873 
4874 	/* add tx FIFO count = reg_value[15..8] */
4875 	total_count += (reg_value >> 8) & 0xff;
4876 
4877 	/* if transmitter active add one byte for shift register */
4878 	if (info->tx_active)
4879 		total_count++;
4880 
4881 	return total_count;
4882 }
4883 
4884 /*
4885  * load data into transmit DMA buffer ring and start transmitter if needed
4886  * return true if data accepted, otherwise false (buffers full)
4887  */
4888 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4889 {
4890 	unsigned short count;
4891 	unsigned int i;
4892 	struct slgt_desc *d;
4893 
4894 	/* check required buffer space */
4895 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4896 		return false;
4897 
4898 	DBGDATA(info, buf, size, "tx");
4899 
4900 	/*
4901 	 * copy data to one or more DMA buffers in circular ring
4902 	 * tbuf_start   = first buffer for this data
4903 	 * tbuf_current = next free buffer
4904 	 *
4905 	 * Copy all data before making data visible to DMA controller by
4906 	 * setting descriptor count of the first buffer.
4907 	 * This prevents an active DMA controller from reading the first DMA
4908 	 * buffers of a frame and stopping before the final buffers are filled.
4909 	 */
4910 
4911 	info->tbuf_start = i = info->tbuf_current;
4912 
4913 	while (size) {
4914 		d = &info->tbufs[i];
4915 
4916 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4917 		memcpy(d->buf, buf, count);
4918 
4919 		size -= count;
4920 		buf  += count;
4921 
4922 		/*
4923 		 * set EOF bit for last buffer of HDLC frame or
4924 		 * for every buffer in raw mode
4925 		 */
4926 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4927 		    info->params.mode == MGSL_MODE_RAW)
4928 			set_desc_eof(*d, 1);
4929 		else
4930 			set_desc_eof(*d, 0);
4931 
4932 		/* set descriptor count for all but first buffer */
4933 		if (i != info->tbuf_start)
4934 			set_desc_count(*d, count);
4935 		d->buf_count = count;
4936 
4937 		if (++i == info->tbuf_count)
4938 			i = 0;
4939 	}
4940 
4941 	info->tbuf_current = i;
4942 
4943 	/* set first buffer count to make new data visible to DMA controller */
4944 	d = &info->tbufs[info->tbuf_start];
4945 	set_desc_count(*d, d->buf_count);
4946 
4947 	/* start transmitter if needed and update transmit timeout */
4948 	if (!info->tx_active)
4949 		tx_start(info);
4950 	update_tx_timer(info);
4951 
4952 	return true;
4953 }
4954 
4955 static int register_test(struct slgt_info *info)
4956 {
4957 	static unsigned short patterns[] =
4958 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4959 	static unsigned int count = ARRAY_SIZE(patterns);
4960 	unsigned int i;
4961 	int rc = 0;
4962 
4963 	for (i=0 ; i < count ; i++) {
4964 		wr_reg16(info, TIR, patterns[i]);
4965 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4966 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4967 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4968 			rc = -ENODEV;
4969 			break;
4970 		}
4971 	}
4972 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4973 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4974 	return rc;
4975 }
4976 
4977 static int irq_test(struct slgt_info *info)
4978 {
4979 	unsigned long timeout;
4980 	unsigned long flags;
4981 	struct tty_struct *oldtty = info->port.tty;
4982 	u32 speed = info->params.data_rate;
4983 
4984 	info->params.data_rate = 921600;
4985 	info->port.tty = NULL;
4986 
4987 	spin_lock_irqsave(&info->lock, flags);
4988 	async_mode(info);
4989 	slgt_irq_on(info, IRQ_TXIDLE);
4990 
4991 	/* enable transmitter */
4992 	wr_reg16(info, TCR,
4993 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4994 
4995 	/* write one byte and wait for tx idle */
4996 	wr_reg16(info, TDR, 0);
4997 
4998 	/* assume failure */
4999 	info->init_error = DiagStatus_IrqFailure;
5000 	info->irq_occurred = false;
5001 
5002 	spin_unlock_irqrestore(&info->lock, flags);
5003 
5004 	timeout=100;
5005 	while(timeout-- && !info->irq_occurred)
5006 		msleep_interruptible(10);
5007 
5008 	spin_lock_irqsave(&info->lock,flags);
5009 	reset_port(info);
5010 	spin_unlock_irqrestore(&info->lock,flags);
5011 
5012 	info->params.data_rate = speed;
5013 	info->port.tty = oldtty;
5014 
5015 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
5016 	return info->irq_occurred ? 0 : -ENODEV;
5017 }
5018 
5019 static int loopback_test_rx(struct slgt_info *info)
5020 {
5021 	unsigned char *src, *dest;
5022 	int count;
5023 
5024 	if (desc_complete(info->rbufs[0])) {
5025 		count = desc_count(info->rbufs[0]);
5026 		src   = info->rbufs[0].buf;
5027 		dest  = info->tmp_rbuf;
5028 
5029 		for( ; count ; count-=2, src+=2) {
5030 			/* src=data byte (src+1)=status byte */
5031 			if (!(*(src+1) & (BIT9 + BIT8))) {
5032 				*dest = *src;
5033 				dest++;
5034 				info->tmp_rbuf_count++;
5035 			}
5036 		}
5037 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
5038 		return 1;
5039 	}
5040 	return 0;
5041 }
5042 
5043 static int loopback_test(struct slgt_info *info)
5044 {
5045 #define TESTFRAMESIZE 20
5046 
5047 	unsigned long timeout;
5048 	u16 count = TESTFRAMESIZE;
5049 	unsigned char buf[TESTFRAMESIZE];
5050 	int rc = -ENODEV;
5051 	unsigned long flags;
5052 
5053 	struct tty_struct *oldtty = info->port.tty;
5054 	MGSL_PARAMS params;
5055 
5056 	memcpy(&params, &info->params, sizeof(params));
5057 
5058 	info->params.mode = MGSL_MODE_ASYNC;
5059 	info->params.data_rate = 921600;
5060 	info->params.loopback = 1;
5061 	info->port.tty = NULL;
5062 
5063 	/* build and send transmit frame */
5064 	for (count = 0; count < TESTFRAMESIZE; ++count)
5065 		buf[count] = (unsigned char)count;
5066 
5067 	info->tmp_rbuf_count = 0;
5068 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
5069 
5070 	/* program hardware for HDLC and enabled receiver */
5071 	spin_lock_irqsave(&info->lock,flags);
5072 	async_mode(info);
5073 	rx_start(info);
5074 	tx_load(info, buf, count);
5075 	spin_unlock_irqrestore(&info->lock, flags);
5076 
5077 	/* wait for receive complete */
5078 	for (timeout = 100; timeout; --timeout) {
5079 		msleep_interruptible(10);
5080 		if (loopback_test_rx(info)) {
5081 			rc = 0;
5082 			break;
5083 		}
5084 	}
5085 
5086 	/* verify received frame length and contents */
5087 	if (!rc && (info->tmp_rbuf_count != count ||
5088 		  memcmp(buf, info->tmp_rbuf, count))) {
5089 		rc = -ENODEV;
5090 	}
5091 
5092 	spin_lock_irqsave(&info->lock,flags);
5093 	reset_adapter(info);
5094 	spin_unlock_irqrestore(&info->lock,flags);
5095 
5096 	memcpy(&info->params, &params, sizeof(info->params));
5097 	info->port.tty = oldtty;
5098 
5099 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5100 	return rc;
5101 }
5102 
5103 static int adapter_test(struct slgt_info *info)
5104 {
5105 	DBGINFO(("testing %s\n", info->device_name));
5106 	if (register_test(info) < 0) {
5107 		printk("register test failure %s addr=%08X\n",
5108 			info->device_name, info->phys_reg_addr);
5109 	} else if (irq_test(info) < 0) {
5110 		printk("IRQ test failure %s IRQ=%d\n",
5111 			info->device_name, info->irq_level);
5112 	} else if (loopback_test(info) < 0) {
5113 		printk("loopback test failure %s\n", info->device_name);
5114 	}
5115 	return info->init_error;
5116 }
5117 
5118 /*
5119  * transmit timeout handler
5120  */
5121 static void tx_timeout(unsigned long context)
5122 {
5123 	struct slgt_info *info = (struct slgt_info*)context;
5124 	unsigned long flags;
5125 
5126 	DBGINFO(("%s tx_timeout\n", info->device_name));
5127 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5128 		info->icount.txtimeout++;
5129 	}
5130 	spin_lock_irqsave(&info->lock,flags);
5131 	tx_stop(info);
5132 	spin_unlock_irqrestore(&info->lock,flags);
5133 
5134 #if SYNCLINK_GENERIC_HDLC
5135 	if (info->netcount)
5136 		hdlcdev_tx_done(info);
5137 	else
5138 #endif
5139 		bh_transmit(info);
5140 }
5141 
5142 /*
5143  * receive buffer polling timer
5144  */
5145 static void rx_timeout(unsigned long context)
5146 {
5147 	struct slgt_info *info = (struct slgt_info*)context;
5148 	unsigned long flags;
5149 
5150 	DBGINFO(("%s rx_timeout\n", info->device_name));
5151 	spin_lock_irqsave(&info->lock, flags);
5152 	info->pending_bh |= BH_RECEIVE;
5153 	spin_unlock_irqrestore(&info->lock, flags);
5154 	bh_handler(&info->task);
5155 }
5156 
5157