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13#include <linux/kernel.h>
14#include <linux/errno.h>
15#include <linux/slab.h>
16#include <linux/sysrq.h>
17#include <linux/tty.h>
18#include <linux/tty_flip.h>
19#include <linux/module.h>
20#include <linux/moduleparam.h>
21#include <linux/usb.h>
22#include <linux/usb/serial.h>
23#include <linux/uaccess.h>
24#include <linux/kfifo.h>
25#include <linux/serial.h>
26
27#ifdef CONFIG_USB_SERIAL_GENERIC
28
29static __u16 vendor = 0x05f9;
30static __u16 product = 0xffff;
31
32module_param(vendor, ushort, 0);
33MODULE_PARM_DESC(vendor, "User specified USB idVendor");
34
35module_param(product, ushort, 0);
36MODULE_PARM_DESC(product, "User specified USB idProduct");
37
38static struct usb_device_id generic_device_ids[2];
39
40
41struct usb_serial_driver usb_serial_generic_device = {
42 .driver = {
43 .owner = THIS_MODULE,
44 .name = "generic",
45 },
46 .id_table = generic_device_ids,
47 .num_ports = 1,
48 .throttle = usb_serial_generic_throttle,
49 .unthrottle = usb_serial_generic_unthrottle,
50 .resume = usb_serial_generic_resume,
51};
52
53static struct usb_serial_driver * const serial_drivers[] = {
54 &usb_serial_generic_device, NULL
55};
56
57#endif
58
59int usb_serial_generic_register(void)
60{
61 int retval = 0;
62
63#ifdef CONFIG_USB_SERIAL_GENERIC
64 generic_device_ids[0].idVendor = vendor;
65 generic_device_ids[0].idProduct = product;
66 generic_device_ids[0].match_flags =
67 USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT;
68
69
70 retval = usb_serial_register_drivers(serial_drivers,
71 "usbserial_generic", generic_device_ids);
72#endif
73 return retval;
74}
75
76void usb_serial_generic_deregister(void)
77{
78#ifdef CONFIG_USB_SERIAL_GENERIC
79
80 usb_serial_deregister_drivers(serial_drivers);
81#endif
82}
83
84int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port)
85{
86 int result = 0;
87 unsigned long flags;
88
89
90 spin_lock_irqsave(&port->lock, flags);
91 port->throttled = 0;
92 port->throttle_req = 0;
93 spin_unlock_irqrestore(&port->lock, flags);
94
95
96 if (port->bulk_in_size)
97 result = usb_serial_generic_submit_read_urbs(port, GFP_KERNEL);
98
99 return result;
100}
101EXPORT_SYMBOL_GPL(usb_serial_generic_open);
102
103void usb_serial_generic_close(struct usb_serial_port *port)
104{
105 unsigned long flags;
106 int i;
107
108 if (port->bulk_out_size) {
109 for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
110 usb_kill_urb(port->write_urbs[i]);
111
112 spin_lock_irqsave(&port->lock, flags);
113 kfifo_reset_out(&port->write_fifo);
114 spin_unlock_irqrestore(&port->lock, flags);
115 }
116 if (port->bulk_in_size) {
117 for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
118 usb_kill_urb(port->read_urbs[i]);
119 }
120}
121EXPORT_SYMBOL_GPL(usb_serial_generic_close);
122
123int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
124 void *dest, size_t size)
125{
126 return kfifo_out_locked(&port->write_fifo, dest, size, &port->lock);
127}
128
129
130
131
132
133
134
135static int usb_serial_generic_write_start(struct usb_serial_port *port)
136{
137 struct urb *urb;
138 int count, result;
139 unsigned long flags;
140 int i;
141
142 if (test_and_set_bit_lock(USB_SERIAL_WRITE_BUSY, &port->flags))
143 return 0;
144retry:
145 spin_lock_irqsave(&port->lock, flags);
146 if (!port->write_urbs_free || !kfifo_len(&port->write_fifo)) {
147 clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
148 spin_unlock_irqrestore(&port->lock, flags);
149 return 0;
150 }
151 i = (int)find_first_bit(&port->write_urbs_free,
152 ARRAY_SIZE(port->write_urbs));
153 spin_unlock_irqrestore(&port->lock, flags);
154
155 urb = port->write_urbs[i];
156 count = port->serial->type->prepare_write_buffer(port,
157 urb->transfer_buffer,
158 port->bulk_out_size);
159 urb->transfer_buffer_length = count;
160 usb_serial_debug_data(&port->dev, __func__, count, urb->transfer_buffer);
161 spin_lock_irqsave(&port->lock, flags);
162 port->tx_bytes += count;
163 spin_unlock_irqrestore(&port->lock, flags);
164
165 clear_bit(i, &port->write_urbs_free);
166 result = usb_submit_urb(urb, GFP_ATOMIC);
167 if (result) {
168 dev_err_console(port, "%s - error submitting urb: %d\n",
169 __func__, result);
170 set_bit(i, &port->write_urbs_free);
171 spin_lock_irqsave(&port->lock, flags);
172 port->tx_bytes -= count;
173 spin_unlock_irqrestore(&port->lock, flags);
174
175 clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
176 return result;
177 }
178
179
180
181 if (!in_irq())
182 goto retry;
183
184 clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
185
186 return 0;
187}
188
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191
192
193
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197
198
199
200int usb_serial_generic_write(struct tty_struct *tty,
201 struct usb_serial_port *port, const unsigned char *buf, int count)
202{
203 int result;
204
205
206 if (!port->bulk_out_size)
207 return -ENODEV;
208
209 if (!count)
210 return 0;
211
212 count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
213 result = usb_serial_generic_write_start(port);
214 if (result)
215 return result;
216
217 return count;
218}
219EXPORT_SYMBOL_GPL(usb_serial_generic_write);
220
221int usb_serial_generic_write_room(struct tty_struct *tty)
222{
223 struct usb_serial_port *port = tty->driver_data;
224 unsigned long flags;
225 int room;
226
227 if (!port->bulk_out_size)
228 return 0;
229
230 spin_lock_irqsave(&port->lock, flags);
231 room = kfifo_avail(&port->write_fifo);
232 spin_unlock_irqrestore(&port->lock, flags);
233
234 dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
235 return room;
236}
237
238int usb_serial_generic_chars_in_buffer(struct tty_struct *tty)
239{
240 struct usb_serial_port *port = tty->driver_data;
241 unsigned long flags;
242 int chars;
243
244 if (!port->bulk_out_size)
245 return 0;
246
247 spin_lock_irqsave(&port->lock, flags);
248 chars = kfifo_len(&port->write_fifo) + port->tx_bytes;
249 spin_unlock_irqrestore(&port->lock, flags);
250
251 dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
252 return chars;
253}
254EXPORT_SYMBOL_GPL(usb_serial_generic_chars_in_buffer);
255
256void usb_serial_generic_wait_until_sent(struct tty_struct *tty, long timeout)
257{
258 struct usb_serial_port *port = tty->driver_data;
259 unsigned int bps;
260 unsigned long period;
261 unsigned long expire;
262
263 bps = tty_get_baud_rate(tty);
264 if (!bps)
265 bps = 9600;
266
267
268
269
270 period = max_t(unsigned long, (10 * HZ / bps), 1);
271 period = min_t(unsigned long, period, timeout);
272
273 dev_dbg(&port->dev, "%s - timeout = %u ms, period = %u ms\n",
274 __func__, jiffies_to_msecs(timeout),
275 jiffies_to_msecs(period));
276 expire = jiffies + timeout;
277 while (!port->serial->type->tx_empty(port)) {
278 schedule_timeout_interruptible(period);
279 if (signal_pending(current))
280 break;
281 if (time_after(jiffies, expire))
282 break;
283 }
284}
285EXPORT_SYMBOL_GPL(usb_serial_generic_wait_until_sent);
286
287static int usb_serial_generic_submit_read_urb(struct usb_serial_port *port,
288 int index, gfp_t mem_flags)
289{
290 int res;
291
292 if (!test_and_clear_bit(index, &port->read_urbs_free))
293 return 0;
294
295 dev_dbg(&port->dev, "%s - urb %d\n", __func__, index);
296
297 res = usb_submit_urb(port->read_urbs[index], mem_flags);
298 if (res) {
299 if (res != -EPERM) {
300 dev_err(&port->dev,
301 "%s - usb_submit_urb failed: %d\n",
302 __func__, res);
303 }
304 set_bit(index, &port->read_urbs_free);
305 return res;
306 }
307
308 return 0;
309}
310
311int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port,
312 gfp_t mem_flags)
313{
314 int res;
315 int i;
316
317 for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
318 res = usb_serial_generic_submit_read_urb(port, i, mem_flags);
319 if (res)
320 goto err;
321 }
322
323 return 0;
324err:
325 for (; i >= 0; --i)
326 usb_kill_urb(port->read_urbs[i]);
327
328 return res;
329}
330EXPORT_SYMBOL_GPL(usb_serial_generic_submit_read_urbs);
331
332void usb_serial_generic_process_read_urb(struct urb *urb)
333{
334 struct usb_serial_port *port = urb->context;
335 char *ch = (char *)urb->transfer_buffer;
336 int i;
337
338 if (!urb->actual_length)
339 return;
340
341
342
343
344 if (!port->port.console || !port->sysrq)
345 tty_insert_flip_string(&port->port, ch, urb->actual_length);
346 else {
347 for (i = 0; i < urb->actual_length; i++, ch++) {
348 if (!usb_serial_handle_sysrq_char(port, *ch))
349 tty_insert_flip_char(&port->port, *ch, TTY_NORMAL);
350 }
351 }
352 tty_flip_buffer_push(&port->port);
353}
354EXPORT_SYMBOL_GPL(usb_serial_generic_process_read_urb);
355
356void usb_serial_generic_read_bulk_callback(struct urb *urb)
357{
358 struct usb_serial_port *port = urb->context;
359 unsigned char *data = urb->transfer_buffer;
360 unsigned long flags;
361 int i;
362
363 for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
364 if (urb == port->read_urbs[i])
365 break;
366 }
367 set_bit(i, &port->read_urbs_free);
368
369 dev_dbg(&port->dev, "%s - urb %d, len %d\n", __func__, i,
370 urb->actual_length);
371
372 if (urb->status) {
373 dev_dbg(&port->dev, "%s - non-zero urb status: %d\n",
374 __func__, urb->status);
375 return;
376 }
377
378 usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
379 port->serial->type->process_read_urb(urb);
380
381
382 spin_lock_irqsave(&port->lock, flags);
383 port->throttled = port->throttle_req;
384 if (!port->throttled) {
385 spin_unlock_irqrestore(&port->lock, flags);
386 usb_serial_generic_submit_read_urb(port, i, GFP_ATOMIC);
387 } else
388 spin_unlock_irqrestore(&port->lock, flags);
389}
390EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback);
391
392void usb_serial_generic_write_bulk_callback(struct urb *urb)
393{
394 unsigned long flags;
395 struct usb_serial_port *port = urb->context;
396 int status = urb->status;
397 int i;
398
399 for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
400 if (port->write_urbs[i] == urb)
401 break;
402
403 spin_lock_irqsave(&port->lock, flags);
404 port->tx_bytes -= urb->transfer_buffer_length;
405 set_bit(i, &port->write_urbs_free);
406 spin_unlock_irqrestore(&port->lock, flags);
407
408 if (status) {
409 dev_dbg(&port->dev, "%s - non-zero urb status: %d\n",
410 __func__, status);
411
412 spin_lock_irqsave(&port->lock, flags);
413 kfifo_reset_out(&port->write_fifo);
414 spin_unlock_irqrestore(&port->lock, flags);
415 } else {
416 usb_serial_generic_write_start(port);
417 }
418
419 usb_serial_port_softint(port);
420}
421EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
422
423void usb_serial_generic_throttle(struct tty_struct *tty)
424{
425 struct usb_serial_port *port = tty->driver_data;
426 unsigned long flags;
427
428
429
430 spin_lock_irqsave(&port->lock, flags);
431 port->throttle_req = 1;
432 spin_unlock_irqrestore(&port->lock, flags);
433}
434EXPORT_SYMBOL_GPL(usb_serial_generic_throttle);
435
436void usb_serial_generic_unthrottle(struct tty_struct *tty)
437{
438 struct usb_serial_port *port = tty->driver_data;
439 int was_throttled;
440
441
442 spin_lock_irq(&port->lock);
443 was_throttled = port->throttled;
444 port->throttled = port->throttle_req = 0;
445 spin_unlock_irq(&port->lock);
446
447 if (was_throttled)
448 usb_serial_generic_submit_read_urbs(port, GFP_KERNEL);
449}
450EXPORT_SYMBOL_GPL(usb_serial_generic_unthrottle);
451
452static bool usb_serial_generic_msr_changed(struct tty_struct *tty,
453 unsigned long arg, struct async_icount *cprev)
454{
455 struct usb_serial_port *port = tty->driver_data;
456 struct async_icount cnow;
457 unsigned long flags;
458 bool ret;
459
460
461
462
463
464 if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags))
465 return true;
466
467 spin_lock_irqsave(&port->lock, flags);
468 cnow = port->icount;
469 spin_unlock_irqrestore(&port->lock, flags);
470
471 ret = ((arg & TIOCM_RNG) && (cnow.rng != cprev->rng)) ||
472 ((arg & TIOCM_DSR) && (cnow.dsr != cprev->dsr)) ||
473 ((arg & TIOCM_CD) && (cnow.dcd != cprev->dcd)) ||
474 ((arg & TIOCM_CTS) && (cnow.cts != cprev->cts));
475
476 *cprev = cnow;
477
478 return ret;
479}
480
481int usb_serial_generic_tiocmiwait(struct tty_struct *tty, unsigned long arg)
482{
483 struct usb_serial_port *port = tty->driver_data;
484 struct async_icount cnow;
485 unsigned long flags;
486 int ret;
487
488 spin_lock_irqsave(&port->lock, flags);
489 cnow = port->icount;
490 spin_unlock_irqrestore(&port->lock, flags);
491
492 ret = wait_event_interruptible(port->port.delta_msr_wait,
493 usb_serial_generic_msr_changed(tty, arg, &cnow));
494 if (!ret && !test_bit(ASYNCB_INITIALIZED, &port->port.flags))
495 ret = -EIO;
496
497 return ret;
498}
499EXPORT_SYMBOL_GPL(usb_serial_generic_tiocmiwait);
500
501int usb_serial_generic_get_icount(struct tty_struct *tty,
502 struct serial_icounter_struct *icount)
503{
504 struct usb_serial_port *port = tty->driver_data;
505 struct async_icount cnow;
506 unsigned long flags;
507
508 spin_lock_irqsave(&port->lock, flags);
509 cnow = port->icount;
510 spin_unlock_irqrestore(&port->lock, flags);
511
512 icount->cts = cnow.cts;
513 icount->dsr = cnow.dsr;
514 icount->rng = cnow.rng;
515 icount->dcd = cnow.dcd;
516 icount->tx = cnow.tx;
517 icount->rx = cnow.rx;
518 icount->frame = cnow.frame;
519 icount->parity = cnow.parity;
520 icount->overrun = cnow.overrun;
521 icount->brk = cnow.brk;
522 icount->buf_overrun = cnow.buf_overrun;
523
524 return 0;
525}
526EXPORT_SYMBOL_GPL(usb_serial_generic_get_icount);
527
528#ifdef CONFIG_MAGIC_SYSRQ
529int usb_serial_handle_sysrq_char(struct usb_serial_port *port, unsigned int ch)
530{
531 if (port->sysrq && port->port.console) {
532 if (ch && time_before(jiffies, port->sysrq)) {
533 handle_sysrq(ch);
534 port->sysrq = 0;
535 return 1;
536 }
537 port->sysrq = 0;
538 }
539 return 0;
540}
541#else
542int usb_serial_handle_sysrq_char(struct usb_serial_port *port, unsigned int ch)
543{
544 return 0;
545}
546#endif
547EXPORT_SYMBOL_GPL(usb_serial_handle_sysrq_char);
548
549int usb_serial_handle_break(struct usb_serial_port *port)
550{
551 if (!port->sysrq) {
552 port->sysrq = jiffies + HZ*5;
553 return 1;
554 }
555 port->sysrq = 0;
556 return 0;
557}
558EXPORT_SYMBOL_GPL(usb_serial_handle_break);
559
560
561
562
563
564
565
566void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
567 struct tty_struct *tty, unsigned int status)
568{
569 struct tty_port *port = &usb_port->port;
570
571 dev_dbg(&usb_port->dev, "%s - status %d\n", __func__, status);
572
573 if (status)
574 wake_up_interruptible(&port->open_wait);
575 else if (tty && !C_CLOCAL(tty))
576 tty_hangup(tty);
577}
578EXPORT_SYMBOL_GPL(usb_serial_handle_dcd_change);
579
580int usb_serial_generic_resume(struct usb_serial *serial)
581{
582 struct usb_serial_port *port;
583 int i, c = 0, r;
584
585 for (i = 0; i < serial->num_ports; i++) {
586 port = serial->port[i];
587 if (!test_bit(ASYNCB_INITIALIZED, &port->port.flags))
588 continue;
589
590 if (port->bulk_in_size) {
591 r = usb_serial_generic_submit_read_urbs(port,
592 GFP_NOIO);
593 if (r < 0)
594 c++;
595 }
596
597 if (port->bulk_out_size) {
598 r = usb_serial_generic_write_start(port);
599 if (r < 0)
600 c++;
601 }
602 }
603
604 return c ? -EIO : 0;
605}
606EXPORT_SYMBOL_GPL(usb_serial_generic_resume);
607