Merge branch 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6] / drivers / usb / serial / empeg.c
1 /*
2  * USB Empeg empeg-car player driver
3  *
4  *      Copyright (C) 2000, 2001
5  *          Gary Brubaker (xavyer@ix.netcom.com)
6  *
7  *      Copyright (C) 1999 - 2001
8  *          Greg Kroah-Hartman (greg@kroah.com)
9  *
10  *      This program is free software; you can redistribute it and/or modify
11  *      it under the terms of the GNU General Public License, as published by
12  *      the Free Software Foundation, version 2.
13  *
14  * See Documentation/usb/usb-serial.txt for more information on using this
15  * driver
16  *
17  * (07/16/2001) gb
18  *      remove unused code in empeg_close() (thanks to Oliver Neukum for
19  *      pointing this out) and rewrote empeg_set_termios().
20  *
21  * (05/30/2001) gkh
22  *      switched from using spinlock to a semaphore, which fixes lots of
23  * problems.
24  *
25  * (04/08/2001) gb
26  *      Identify version on module load.
27  *
28  * (01/22/2001) gb
29  *      Added write_room() and chars_in_buffer() support.
30  *
31  * (12/21/2000) gb
32  *      Moved termio stuff inside the port->active check.
33  *      Moved MOD_DEC_USE_COUNT to end of empeg_close().
34  *
35  * (12/03/2000) gb
36  *      Added port->port.tty->ldisc.set_termios(port->port.tty, NULL) to
37  *      empeg_open(). This notifies the tty driver that the termios have
38  *      changed.
39  *
40  * (11/13/2000) gb
41  *      Moved tty->low_latency = 1 from empeg_read_bulk_callback() to
42  *      empeg_open() (It only needs to be set once - Doh!)
43  *
44  * (11/11/2000) gb
45  *      Updated to work with id_table structure.
46  *
47  * (11/04/2000) gb
48  *      Forked this from visor.c, and hacked it up to work with an
49  *      Empeg ltd. empeg-car player.  Constructive criticism welcomed.
50  *      I would like to say, 'Thank You' to Greg Kroah-Hartman for the
51  *      use of his code, and for his guidance, advice and patience. :)
52  *      A 'Thank You' is in order for John Ripley of Empeg ltd for his
53  *      advice, and patience too.
54  *
55  */
56
57 #include <linux/kernel.h>
58 #include <linux/errno.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #include <linux/tty.h>
62 #include <linux/tty_driver.h>
63 #include <linux/tty_flip.h>
64 #include <linux/module.h>
65 #include <linux/spinlock.h>
66 #include <linux/uaccess.h>
67 #include <linux/usb.h>
68 #include <linux/usb/serial.h>
69
70 static int debug;
71
72 /*
73  * Version Information
74  */
75 #define DRIVER_VERSION "v1.2"
76 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Gary Brubaker <xavyer@ix.netcom.com>"
77 #define DRIVER_DESC "USB Empeg Mark I/II Driver"
78
79 #define EMPEG_VENDOR_ID                 0x084f
80 #define EMPEG_PRODUCT_ID                0x0001
81
82 /* function prototypes for an empeg-car player */
83 static int  empeg_open(struct tty_struct *tty, struct usb_serial_port *port,
84                                                 struct file *filp);
85 static void empeg_close(struct tty_struct *tty, struct usb_serial_port *port,
86                                                 struct file *filp);
87 static int  empeg_write(struct tty_struct *tty, struct usb_serial_port *port,
88                                                 const unsigned char *buf,
89                                                 int count);
90 static int  empeg_write_room(struct tty_struct *tty);
91 static int  empeg_chars_in_buffer(struct tty_struct *tty);
92 static void empeg_throttle(struct tty_struct *tty);
93 static void empeg_unthrottle(struct tty_struct *tty);
94 static int  empeg_startup(struct usb_serial *serial);
95 static void empeg_shutdown(struct usb_serial *serial);
96 static void empeg_set_termios(struct tty_struct *tty,
97                 struct usb_serial_port *port, struct ktermios *old_termios);
98 static void empeg_write_bulk_callback(struct urb *urb);
99 static void empeg_read_bulk_callback(struct urb *urb);
100
101 static struct usb_device_id id_table [] = {
102         { USB_DEVICE(EMPEG_VENDOR_ID, EMPEG_PRODUCT_ID) },
103         { }                                     /* Terminating entry */
104 };
105
106 MODULE_DEVICE_TABLE(usb, id_table);
107
108 static struct usb_driver empeg_driver = {
109         .name =         "empeg",
110         .probe =        usb_serial_probe,
111         .disconnect =   usb_serial_disconnect,
112         .id_table =     id_table,
113         .no_dynamic_id =        1,
114 };
115
116 static struct usb_serial_driver empeg_device = {
117         .driver = {
118                 .owner =        THIS_MODULE,
119                 .name =         "empeg",
120         },
121         .id_table =             id_table,
122         .usb_driver =           &empeg_driver,
123         .num_ports =            1,
124         .open =                 empeg_open,
125         .close =                empeg_close,
126         .throttle =             empeg_throttle,
127         .unthrottle =           empeg_unthrottle,
128         .attach =               empeg_startup,
129         .shutdown =             empeg_shutdown,
130         .set_termios =          empeg_set_termios,
131         .write =                empeg_write,
132         .write_room =           empeg_write_room,
133         .chars_in_buffer =      empeg_chars_in_buffer,
134         .write_bulk_callback =  empeg_write_bulk_callback,
135         .read_bulk_callback =   empeg_read_bulk_callback,
136 };
137
138 #define NUM_URBS                        16
139 #define URB_TRANSFER_BUFFER_SIZE        4096
140
141 static struct urb       *write_urb_pool[NUM_URBS];
142 static spinlock_t       write_urb_pool_lock;
143 static int              bytes_in;
144 static int              bytes_out;
145
146 /******************************************************************************
147  * Empeg specific driver functions
148  ******************************************************************************/
149 static int empeg_open(struct tty_struct *tty, struct usb_serial_port *port,
150                                 struct file *filp)
151 {
152         struct usb_serial *serial = port->serial;
153         int result = 0;
154
155         dbg("%s - port %d", __func__, port->number);
156
157         /* Force default termio settings */
158         empeg_set_termios(tty, port, NULL) ;
159
160         bytes_in = 0;
161         bytes_out = 0;
162
163         /* Start reading from the device */
164         usb_fill_bulk_urb(
165                 port->read_urb,
166                 serial->dev,
167                 usb_rcvbulkpipe(serial->dev,
168                         port->bulk_in_endpointAddress),
169                 port->read_urb->transfer_buffer,
170                 port->read_urb->transfer_buffer_length,
171                 empeg_read_bulk_callback,
172                 port);
173
174         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
175
176         if (result)
177                 dev_err(&port->dev,
178                         "%s - failed submitting read urb, error %d\n",
179                                                         __func__, result);
180
181         return result;
182 }
183
184
185 static void empeg_close(struct tty_struct *tty, struct usb_serial_port *port,
186                                 struct file *filp)
187 {
188         dbg("%s - port %d", __func__, port->number);
189
190         /* shutdown our bulk read */
191         usb_kill_urb(port->read_urb);
192         /* Uncomment the following line if you want to see some statistics in your syslog */
193         /* dev_info (&port->dev, "Bytes In = %d  Bytes Out = %d\n", bytes_in, bytes_out); */
194 }
195
196
197 static int empeg_write(struct tty_struct *tty, struct usb_serial_port *port,
198                                         const unsigned char *buf, int count)
199 {
200         struct usb_serial *serial = port->serial;
201         struct urb *urb;
202         const unsigned char *current_position = buf;
203         unsigned long flags;
204         int status;
205         int i;
206         int bytes_sent = 0;
207         int transfer_size;
208
209         dbg("%s - port %d", __func__, port->number);
210
211         while (count > 0) {
212                 /* try to find a free urb in our list of them */
213                 urb = NULL;
214
215                 spin_lock_irqsave(&write_urb_pool_lock, flags);
216
217                 for (i = 0; i < NUM_URBS; ++i) {
218                         if (write_urb_pool[i]->status != -EINPROGRESS) {
219                                 urb = write_urb_pool[i];
220                                 break;
221                         }
222                 }
223
224                 spin_unlock_irqrestore(&write_urb_pool_lock, flags);
225
226                 if (urb == NULL) {
227                         dbg("%s - no more free urbs", __func__);
228                         goto exit;
229                 }
230
231                 if (urb->transfer_buffer == NULL) {
232                         urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
233                         if (urb->transfer_buffer == NULL) {
234                                 dev_err(&port->dev,
235                                         "%s no more kernel memory...\n",
236                                                                 __func__);
237                                 goto exit;
238                         }
239                 }
240
241                 transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
242
243                 memcpy(urb->transfer_buffer, current_position, transfer_size);
244
245                 usb_serial_debug_data(debug, &port->dev, __func__, transfer_size, urb->transfer_buffer);
246
247                 /* build up our urb */
248                 usb_fill_bulk_urb(
249                         urb,
250                         serial->dev,
251                         usb_sndbulkpipe(serial->dev,
252                                         port->bulk_out_endpointAddress),
253                         urb->transfer_buffer,
254                         transfer_size,
255                         empeg_write_bulk_callback,
256                         port);
257
258                 /* send it down the pipe */
259                 status = usb_submit_urb(urb, GFP_ATOMIC);
260                 if (status) {
261                         dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n", __func__, status);
262                         bytes_sent = status;
263                         break;
264                 }
265
266                 current_position += transfer_size;
267                 bytes_sent += transfer_size;
268                 count -= transfer_size;
269                 bytes_out += transfer_size;
270
271         }
272 exit:
273         return bytes_sent;
274 }
275
276
277 static int empeg_write_room(struct tty_struct *tty)
278 {
279         struct usb_serial_port *port = tty->driver_data;
280         unsigned long flags;
281         int i;
282         int room = 0;
283
284         dbg("%s - port %d", __func__, port->number);
285
286         spin_lock_irqsave(&write_urb_pool_lock, flags);
287         /* tally up the number of bytes available */
288         for (i = 0; i < NUM_URBS; ++i) {
289                 if (write_urb_pool[i]->status != -EINPROGRESS)
290                         room += URB_TRANSFER_BUFFER_SIZE;
291         }
292         spin_unlock_irqrestore(&write_urb_pool_lock, flags);
293         dbg("%s - returns %d", __func__, room);
294         return room;
295
296 }
297
298
299 static int empeg_chars_in_buffer(struct tty_struct *tty)
300 {
301         struct usb_serial_port *port = tty->driver_data;
302         unsigned long flags;
303         int i;
304         int chars = 0;
305
306         dbg("%s - port %d", __func__, port->number);
307
308         spin_lock_irqsave(&write_urb_pool_lock, flags);
309
310         /* tally up the number of bytes waiting */
311         for (i = 0; i < NUM_URBS; ++i) {
312                 if (write_urb_pool[i]->status == -EINPROGRESS)
313                         chars += URB_TRANSFER_BUFFER_SIZE;
314         }
315
316         spin_unlock_irqrestore(&write_urb_pool_lock, flags);
317         dbg("%s - returns %d", __func__, chars);
318         return chars;
319 }
320
321
322 static void empeg_write_bulk_callback(struct urb *urb)
323 {
324         struct usb_serial_port *port = urb->context;
325         int status = urb->status;
326
327         dbg("%s - port %d", __func__, port->number);
328
329         if (status) {
330                 dbg("%s - nonzero write bulk status received: %d",
331                     __func__, status);
332                 return;
333         }
334
335         usb_serial_port_softint(port);
336 }
337
338
339 static void empeg_read_bulk_callback(struct urb *urb)
340 {
341         struct usb_serial_port *port = urb->context;
342         struct tty_struct *tty;
343         unsigned char *data = urb->transfer_buffer;
344         int result;
345         int status = urb->status;
346
347         dbg("%s - port %d", __func__, port->number);
348
349         if (status) {
350                 dbg("%s - nonzero read bulk status received: %d",
351                     __func__, status);
352                 return;
353         }
354
355         usb_serial_debug_data(debug, &port->dev, __func__,
356                                                 urb->actual_length, data);
357         tty = port->port.tty;
358
359         if (urb->actual_length) {
360                 tty_buffer_request_room(tty, urb->actual_length);
361                 tty_insert_flip_string(tty, data, urb->actual_length);
362                 tty_flip_buffer_push(tty);
363                 bytes_in += urb->actual_length;
364         }
365
366         /* Continue trying to always read  */
367         usb_fill_bulk_urb(
368                 port->read_urb,
369                 port->serial->dev,
370                 usb_rcvbulkpipe(port->serial->dev,
371                         port->bulk_in_endpointAddress),
372                 port->read_urb->transfer_buffer,
373                 port->read_urb->transfer_buffer_length,
374                 empeg_read_bulk_callback,
375                 port);
376
377         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
378
379         if (result)
380                 dev_err(&urb->dev->dev,
381                         "%s - failed resubmitting read urb, error %d\n",
382                                                         __func__, result);
383
384         return;
385
386 }
387
388
389 static void empeg_throttle(struct tty_struct *tty)
390 {
391         struct usb_serial_port *port = tty->driver_data;
392         dbg("%s - port %d", __func__, port->number);
393         usb_kill_urb(port->read_urb);
394 }
395
396
397 static void empeg_unthrottle(struct tty_struct *tty)
398 {
399         struct usb_serial_port *port = tty->driver_data;
400         int result;
401         dbg("%s - port %d", __func__, port->number);
402
403         port->read_urb->dev = port->serial->dev;
404         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
405         if (result)
406                 dev_err(&port->dev,
407                         "%s - failed submitting read urb, error %d\n",
408                                                         __func__, result);
409 }
410
411
412 static int  empeg_startup(struct usb_serial *serial)
413 {
414         int r;
415
416         dbg("%s", __func__);
417
418         if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
419                 err("active config #%d != 1 ??",
420                         serial->dev->actconfig->desc.bConfigurationValue);
421                 return -ENODEV;
422         }
423         dbg("%s - reset config", __func__);
424         r = usb_reset_configuration(serial->dev);
425
426         /* continue on with initialization */
427         return r;
428
429 }
430
431
432 static void empeg_shutdown(struct usb_serial *serial)
433 {
434         dbg("%s", __func__);
435 }
436
437
438 static void empeg_set_termios(struct tty_struct *tty,
439                 struct usb_serial_port *port, struct ktermios *old_termios)
440 {
441         struct ktermios *termios = tty->termios;
442         dbg("%s - port %d", __func__, port->number);
443
444         /*
445          * The empeg-car player wants these particular tty settings.
446          * You could, for example, change the baud rate, however the
447          * player only supports 115200 (currently), so there is really
448          * no point in support for changes to the tty settings.
449          * (at least for now)
450          *
451          * The default requirements for this device are:
452          */
453         termios->c_iflag
454                 &= ~(IGNBRK     /* disable ignore break */
455                 | BRKINT        /* disable break causes interrupt */
456                 | PARMRK        /* disable mark parity errors */
457                 | ISTRIP        /* disable clear high bit of input characters */
458                 | INLCR         /* disable translate NL to CR */
459                 | IGNCR         /* disable ignore CR */
460                 | ICRNL         /* disable translate CR to NL */
461                 | IXON);        /* disable enable XON/XOFF flow control */
462
463         termios->c_oflag
464                 &= ~OPOST;      /* disable postprocess output characters */
465
466         termios->c_lflag
467                 &= ~(ECHO       /* disable echo input characters */
468                 | ECHONL        /* disable echo new line */
469                 | ICANON        /* disable erase, kill, werase, and rprnt special characters */
470                 | ISIG          /* disable interrupt, quit, and suspend special characters */
471                 | IEXTEN);      /* disable non-POSIX special characters */
472
473         termios->c_cflag
474                 &= ~(CSIZE      /* no size */
475                 | PARENB        /* disable parity bit */
476                 | CBAUD);       /* clear current baud rate */
477
478         termios->c_cflag
479                 |= CS8;         /* character size 8 bits */
480
481         /*
482          * Force low_latency on; otherwise the pushes are scheduled;
483          * this is bad as it opens up the possibility of dropping bytes
484          * on the floor.  We don't want to drop bytes on the floor. :)
485          */
486         tty->low_latency = 1;
487         tty_encode_baud_rate(tty, 115200, 115200);
488 }
489
490
491 static int __init empeg_init(void)
492 {
493         struct urb *urb;
494         int i, retval;
495
496         /* create our write urb pool and transfer buffers */
497         spin_lock_init(&write_urb_pool_lock);
498         for (i = 0; i < NUM_URBS; ++i) {
499                 urb = usb_alloc_urb(0, GFP_KERNEL);
500                 write_urb_pool[i] = urb;
501                 if (urb == NULL) {
502                         err("No more urbs???");
503                         continue;
504                 }
505
506                 urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
507                                                                 GFP_KERNEL);
508                 if (!urb->transfer_buffer) {
509                         err("%s - out of memory for urb buffers.",
510                             __func__);
511                         continue;
512                 }
513         }
514
515         retval = usb_serial_register(&empeg_device);
516         if (retval)
517                 goto failed_usb_serial_register;
518         retval = usb_register(&empeg_driver);
519         if (retval)
520                 goto failed_usb_register;
521
522         info(DRIVER_VERSION ":" DRIVER_DESC);
523
524         return 0;
525 failed_usb_register:
526         usb_serial_deregister(&empeg_device);
527 failed_usb_serial_register:
528         for (i = 0; i < NUM_URBS; ++i) {
529                 if (write_urb_pool[i]) {
530                         kfree(write_urb_pool[i]->transfer_buffer);
531                         usb_free_urb(write_urb_pool[i]);
532                 }
533         }
534         return retval;
535 }
536
537
538 static void __exit empeg_exit(void)
539 {
540         int i;
541         unsigned long flags;
542
543         usb_deregister(&empeg_driver);
544         usb_serial_deregister(&empeg_device);
545
546         spin_lock_irqsave(&write_urb_pool_lock, flags);
547
548         for (i = 0; i < NUM_URBS; ++i) {
549                 if (write_urb_pool[i]) {
550                         /* FIXME - uncomment the following usb_kill_urb call
551                          * when the host controllers get fixed to set urb->dev
552                          * = NULL after the urb is finished.  Otherwise this
553                          * call oopses. */
554                         /* usb_kill_urb(write_urb_pool[i]); */
555                         kfree(write_urb_pool[i]->transfer_buffer);
556                         usb_free_urb(write_urb_pool[i]);
557                 }
558         }
559         spin_unlock_irqrestore(&write_urb_pool_lock, flags);
560 }
561
562
563 module_init(empeg_init);
564 module_exit(empeg_exit);
565
566 MODULE_AUTHOR(DRIVER_AUTHOR);
567 MODULE_DESCRIPTION(DRIVER_DESC);
568 MODULE_LICENSE("GPL");
569
570 module_param(debug, bool, S_IRUGO | S_IWUSR);
571 MODULE_PARM_DESC(debug, "Debug enabled or not");