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[~andy/linux] / drivers / usb / serial / cypress_m8.c
1 /*
2  * USB Cypress M8 driver
3  *
4  *      Copyright (C) 2004
5  *          Lonnie Mendez (dignome@gmail.com)
6  *      Copyright (C) 2003,2004
7  *          Neil Whelchel (koyama@firstlight.net)
8  *
9  *      This program is free software; you can redistribute it and/or modify
10  *      it under the terms of the GNU General Public License as published by
11  *      the Free Software Foundation; either version 2 of the License, or
12  *      (at your option) any later version.
13  *
14  * See Documentation/usb/usb-serial.txt for more information on using this
15  * driver
16  *
17  * See http://geocities.com/i0xox0i for information on this driver and the
18  * earthmate usb device.
19  */
20
21 /* Thanks to Neil Whelchel for writing the first cypress m8 implementation
22    for linux. */
23 /* Thanks to cypress for providing references for the hid reports. */
24 /* Thanks to Jiang Zhang for providing links and for general help. */
25 /* Code originates and was built up from ftdi_sio, belkin, pl2303 and others.*/
26
27
28 #include <linux/kernel.h>
29 #include <linux/errno.h>
30 #include <linux/init.h>
31 #include <linux/slab.h>
32 #include <linux/tty.h>
33 #include <linux/tty_driver.h>
34 #include <linux/tty_flip.h>
35 #include <linux/module.h>
36 #include <linux/moduleparam.h>
37 #include <linux/spinlock.h>
38 #include <linux/usb.h>
39 #include <linux/usb/serial.h>
40 #include <linux/serial.h>
41 #include <linux/kfifo.h>
42 #include <linux/delay.h>
43 #include <linux/uaccess.h>
44 #include <asm/unaligned.h>
45
46 #include "cypress_m8.h"
47
48
49 static bool stats;
50 static int interval;
51 static bool unstable_bauds;
52
53 /*
54  * Version Information
55  */
56 #define DRIVER_VERSION "v1.10"
57 #define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
58 #define DRIVER_DESC "Cypress USB to Serial Driver"
59
60 /* write buffer size defines */
61 #define CYPRESS_BUF_SIZE        1024
62
63 static const struct usb_device_id id_table_earthmate[] = {
64         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
65         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
66         { }                                             /* Terminating entry */
67 };
68
69 static const struct usb_device_id id_table_cyphidcomrs232[] = {
70         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
71         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
72         { }                                             /* Terminating entry */
73 };
74
75 static const struct usb_device_id id_table_nokiaca42v2[] = {
76         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
77         { }                                             /* Terminating entry */
78 };
79
80 static const struct usb_device_id id_table_combined[] = {
81         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
82         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
83         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
84         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
85         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
86         { }                                             /* Terminating entry */
87 };
88
89 MODULE_DEVICE_TABLE(usb, id_table_combined);
90
91 enum packet_format {
92         packet_format_1,  /* b0:status, b1:payload count */
93         packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
94 };
95
96 struct cypress_private {
97         spinlock_t lock;                   /* private lock */
98         int chiptype;                      /* identifier of device, for quirks/etc */
99         int bytes_in;                      /* used for statistics */
100         int bytes_out;                     /* used for statistics */
101         int cmd_count;                     /* used for statistics */
102         int cmd_ctrl;                      /* always set this to 1 before issuing a command */
103         struct kfifo write_fifo;           /* write fifo */
104         int write_urb_in_use;              /* write urb in use indicator */
105         int write_urb_interval;            /* interval to use for write urb */
106         int read_urb_interval;             /* interval to use for read urb */
107         int comm_is_ok;                    /* true if communication is (still) ok */
108         int termios_initialized;
109         __u8 line_control;                 /* holds dtr / rts value */
110         __u8 current_status;               /* received from last read - info on dsr,cts,cd,ri,etc */
111         __u8 current_config;               /* stores the current configuration byte */
112         __u8 rx_flags;                     /* throttling - used from whiteheat/ftdi_sio */
113         enum packet_format pkt_fmt;        /* format to use for packet send / receive */
114         int get_cfg_unsafe;                /* If true, the CYPRESS_GET_CONFIG is unsafe */
115         int baud_rate;                     /* stores current baud rate in
116                                               integer form */
117         int isthrottled;                   /* if throttled, discard reads */
118         wait_queue_head_t delta_msr_wait;  /* used for TIOCMIWAIT */
119         char prev_status, diff_status;     /* used for TIOCMIWAIT */
120         /* we pass a pointer to this as the argument sent to
121            cypress_set_termios old_termios */
122         struct ktermios tmp_termios;       /* stores the old termios settings */
123 };
124
125 /* function prototypes for the Cypress USB to serial device */
126 static int  cypress_earthmate_port_probe(struct usb_serial_port *port);
127 static int  cypress_hidcom_port_probe(struct usb_serial_port *port);
128 static int  cypress_ca42v2_port_probe(struct usb_serial_port *port);
129 static int  cypress_port_remove(struct usb_serial_port *port);
130 static int  cypress_open(struct tty_struct *tty, struct usb_serial_port *port);
131 static void cypress_close(struct usb_serial_port *port);
132 static void cypress_dtr_rts(struct usb_serial_port *port, int on);
133 static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
134                         const unsigned char *buf, int count);
135 static void cypress_send(struct usb_serial_port *port);
136 static int  cypress_write_room(struct tty_struct *tty);
137 static int  cypress_ioctl(struct tty_struct *tty,
138                         unsigned int cmd, unsigned long arg);
139 static void cypress_set_termios(struct tty_struct *tty,
140                         struct usb_serial_port *port, struct ktermios *old);
141 static int  cypress_tiocmget(struct tty_struct *tty);
142 static int  cypress_tiocmset(struct tty_struct *tty,
143                         unsigned int set, unsigned int clear);
144 static int  cypress_chars_in_buffer(struct tty_struct *tty);
145 static void cypress_throttle(struct tty_struct *tty);
146 static void cypress_unthrottle(struct tty_struct *tty);
147 static void cypress_set_dead(struct usb_serial_port *port);
148 static void cypress_read_int_callback(struct urb *urb);
149 static void cypress_write_int_callback(struct urb *urb);
150
151 static struct usb_serial_driver cypress_earthmate_device = {
152         .driver = {
153                 .owner =                THIS_MODULE,
154                 .name =                 "earthmate",
155         },
156         .description =                  "DeLorme Earthmate USB",
157         .id_table =                     id_table_earthmate,
158         .num_ports =                    1,
159         .port_probe =                   cypress_earthmate_port_probe,
160         .port_remove =                  cypress_port_remove,
161         .open =                         cypress_open,
162         .close =                        cypress_close,
163         .dtr_rts =                      cypress_dtr_rts,
164         .write =                        cypress_write,
165         .write_room =                   cypress_write_room,
166         .ioctl =                        cypress_ioctl,
167         .set_termios =                  cypress_set_termios,
168         .tiocmget =                     cypress_tiocmget,
169         .tiocmset =                     cypress_tiocmset,
170         .chars_in_buffer =              cypress_chars_in_buffer,
171         .throttle =                     cypress_throttle,
172         .unthrottle =                   cypress_unthrottle,
173         .read_int_callback =            cypress_read_int_callback,
174         .write_int_callback =           cypress_write_int_callback,
175 };
176
177 static struct usb_serial_driver cypress_hidcom_device = {
178         .driver = {
179                 .owner =                THIS_MODULE,
180                 .name =                 "cyphidcom",
181         },
182         .description =                  "HID->COM RS232 Adapter",
183         .id_table =                     id_table_cyphidcomrs232,
184         .num_ports =                    1,
185         .port_probe =                   cypress_hidcom_port_probe,
186         .port_remove =                  cypress_port_remove,
187         .open =                         cypress_open,
188         .close =                        cypress_close,
189         .dtr_rts =                      cypress_dtr_rts,
190         .write =                        cypress_write,
191         .write_room =                   cypress_write_room,
192         .ioctl =                        cypress_ioctl,
193         .set_termios =                  cypress_set_termios,
194         .tiocmget =                     cypress_tiocmget,
195         .tiocmset =                     cypress_tiocmset,
196         .chars_in_buffer =              cypress_chars_in_buffer,
197         .throttle =                     cypress_throttle,
198         .unthrottle =                   cypress_unthrottle,
199         .read_int_callback =            cypress_read_int_callback,
200         .write_int_callback =           cypress_write_int_callback,
201 };
202
203 static struct usb_serial_driver cypress_ca42v2_device = {
204         .driver = {
205                 .owner =                THIS_MODULE,
206                 .name =                 "nokiaca42v2",
207         },
208         .description =                  "Nokia CA-42 V2 Adapter",
209         .id_table =                     id_table_nokiaca42v2,
210         .num_ports =                    1,
211         .port_probe =                   cypress_ca42v2_port_probe,
212         .port_remove =                  cypress_port_remove,
213         .open =                         cypress_open,
214         .close =                        cypress_close,
215         .dtr_rts =                      cypress_dtr_rts,
216         .write =                        cypress_write,
217         .write_room =                   cypress_write_room,
218         .ioctl =                        cypress_ioctl,
219         .set_termios =                  cypress_set_termios,
220         .tiocmget =                     cypress_tiocmget,
221         .tiocmset =                     cypress_tiocmset,
222         .chars_in_buffer =              cypress_chars_in_buffer,
223         .throttle =                     cypress_throttle,
224         .unthrottle =                   cypress_unthrottle,
225         .read_int_callback =            cypress_read_int_callback,
226         .write_int_callback =           cypress_write_int_callback,
227 };
228
229 static struct usb_serial_driver * const serial_drivers[] = {
230         &cypress_earthmate_device, &cypress_hidcom_device,
231         &cypress_ca42v2_device, NULL
232 };
233
234 /*****************************************************************************
235  * Cypress serial helper functions
236  *****************************************************************************/
237
238
239 static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
240 {
241         struct cypress_private *priv;
242         priv = usb_get_serial_port_data(port);
243
244         if (unstable_bauds)
245                 return new_rate;
246
247         /*
248          * The general purpose firmware for the Cypress M8 allows for
249          * a maximum speed of 57600bps (I have no idea whether DeLorme
250          * chose to use the general purpose firmware or not), if you
251          * need to modify this speed setting for your own project
252          * please add your own chiptype and modify the code likewise.
253          * The Cypress HID->COM device will work successfully up to
254          * 115200bps (but the actual throughput is around 3kBps).
255          */
256         if (port->serial->dev->speed == USB_SPEED_LOW) {
257                 /*
258                  * Mike Isely <isely@pobox.com> 2-Feb-2008: The
259                  * Cypress app note that describes this mechanism
260                  * states the the low-speed part can't handle more
261                  * than 800 bytes/sec, in which case 4800 baud is the
262                  * safest speed for a part like that.
263                  */
264                 if (new_rate > 4800) {
265                         dev_dbg(&port->dev,
266                                 "%s - failed setting baud rate, device incapable speed %d\n",
267                                 __func__, new_rate);
268                         return -1;
269                 }
270         }
271         switch (priv->chiptype) {
272         case CT_EARTHMATE:
273                 if (new_rate <= 600) {
274                         /* 300 and 600 baud rates are supported under
275                          * the generic firmware, but are not used with
276                          * NMEA and SiRF protocols */
277                         dev_dbg(&port->dev,
278                                 "%s - failed setting baud rate, unsupported speed of %d on Earthmate GPS",
279                                 __func__, new_rate);
280                         return -1;
281                 }
282                 break;
283         default:
284                 break;
285         }
286         return new_rate;
287 }
288
289
290 /* This function can either set or retrieve the current serial line settings */
291 static int cypress_serial_control(struct tty_struct *tty,
292         struct usb_serial_port *port, speed_t baud_rate, int data_bits,
293         int stop_bits, int parity_enable, int parity_type, int reset,
294         int cypress_request_type)
295 {
296         int new_baudrate = 0, retval = 0, tries = 0;
297         struct cypress_private *priv;
298         struct device *dev = &port->dev;
299         u8 *feature_buffer;
300         const unsigned int feature_len = 5;
301         unsigned long flags;
302
303         priv = usb_get_serial_port_data(port);
304
305         if (!priv->comm_is_ok)
306                 return -ENODEV;
307
308         feature_buffer = kcalloc(feature_len, sizeof(u8), GFP_KERNEL);
309         if (!feature_buffer)
310                 return -ENOMEM;
311
312         switch (cypress_request_type) {
313         case CYPRESS_SET_CONFIG:
314                 /* 0 means 'Hang up' so doesn't change the true bit rate */
315                 new_baudrate = priv->baud_rate;
316                 if (baud_rate && baud_rate != priv->baud_rate) {
317                         dev_dbg(dev, "%s - baud rate is changing\n", __func__);
318                         retval = analyze_baud_rate(port, baud_rate);
319                         if (retval >= 0) {
320                                 new_baudrate = retval;
321                                 dev_dbg(dev, "%s - New baud rate set to %d\n",
322                                         __func__, new_baudrate);
323                         }
324                 }
325                 dev_dbg(dev, "%s - baud rate is being sent as %d\n", __func__,
326                         new_baudrate);
327
328                 /* fill the feature_buffer with new configuration */
329                 put_unaligned_le32(new_baudrate, feature_buffer);
330                 feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
331                 /* 1 bit gap */
332                 feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
333                 feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
334                 feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
335                 /* 1 bit gap */
336                 feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
337
338                 dev_dbg(dev, "%s - device is being sent this feature report:\n", __func__);
339                 dev_dbg(dev, "%s - %02X - %02X - %02X - %02X - %02X\n", __func__,
340                         feature_buffer[0], feature_buffer[1],
341                         feature_buffer[2], feature_buffer[3],
342                         feature_buffer[4]);
343
344                 do {
345                         retval = usb_control_msg(port->serial->dev,
346                                         usb_sndctrlpipe(port->serial->dev, 0),
347                                         HID_REQ_SET_REPORT,
348                                         USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
349                                         0x0300, 0, feature_buffer,
350                                         feature_len, 500);
351
352                         if (tries++ >= 3)
353                                 break;
354
355                 } while (retval != feature_len &&
356                          retval != -ENODEV);
357
358                 if (retval != feature_len) {
359                         dev_err(dev, "%s - failed sending serial line settings - %d\n",
360                                 __func__, retval);
361                         cypress_set_dead(port);
362                 } else {
363                         spin_lock_irqsave(&priv->lock, flags);
364                         priv->baud_rate = new_baudrate;
365                         priv->current_config = feature_buffer[4];
366                         spin_unlock_irqrestore(&priv->lock, flags);
367                         /* If we asked for a speed change encode it */
368                         if (baud_rate)
369                                 tty_encode_baud_rate(tty,
370                                         new_baudrate, new_baudrate);
371                 }
372         break;
373         case CYPRESS_GET_CONFIG:
374                 if (priv->get_cfg_unsafe) {
375                         /* Not implemented for this device,
376                            and if we try to do it we're likely
377                            to crash the hardware. */
378                         retval = -ENOTTY;
379                         goto out;
380                 }
381                 dev_dbg(dev, "%s - retreiving serial line settings\n", __func__);
382                 do {
383                         retval = usb_control_msg(port->serial->dev,
384                                         usb_rcvctrlpipe(port->serial->dev, 0),
385                                         HID_REQ_GET_REPORT,
386                                         USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
387                                         0x0300, 0, feature_buffer,
388                                         feature_len, 500);
389
390                         if (tries++ >= 3)
391                                 break;
392                 } while (retval != feature_len
393                                                 && retval != -ENODEV);
394
395                 if (retval != feature_len) {
396                         dev_err(dev, "%s - failed to retrieve serial line settings - %d\n",
397                                 __func__, retval);
398                         cypress_set_dead(port);
399                         goto out;
400                 } else {
401                         spin_lock_irqsave(&priv->lock, flags);
402                         /* store the config in one byte, and later
403                            use bit masks to check values */
404                         priv->current_config = feature_buffer[4];
405                         priv->baud_rate = get_unaligned_le32(feature_buffer);
406                         spin_unlock_irqrestore(&priv->lock, flags);
407                 }
408         }
409         spin_lock_irqsave(&priv->lock, flags);
410         ++priv->cmd_count;
411         spin_unlock_irqrestore(&priv->lock, flags);
412 out:
413         kfree(feature_buffer);
414         return retval;
415 } /* cypress_serial_control */
416
417
418 static void cypress_set_dead(struct usb_serial_port *port)
419 {
420         struct cypress_private *priv = usb_get_serial_port_data(port);
421         unsigned long flags;
422
423         spin_lock_irqsave(&priv->lock, flags);
424         if (!priv->comm_is_ok) {
425                 spin_unlock_irqrestore(&priv->lock, flags);
426                 return;
427         }
428         priv->comm_is_ok = 0;
429         spin_unlock_irqrestore(&priv->lock, flags);
430
431         dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
432                 "interval might be too short\n", port->number);
433 }
434
435
436 /*****************************************************************************
437  * Cypress serial driver functions
438  *****************************************************************************/
439
440
441 static int cypress_generic_port_probe(struct usb_serial_port *port)
442 {
443         struct usb_serial *serial = port->serial;
444         struct cypress_private *priv;
445
446         priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
447         if (!priv)
448                 return -ENOMEM;
449
450         priv->comm_is_ok = !0;
451         spin_lock_init(&priv->lock);
452         if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
453                 kfree(priv);
454                 return -ENOMEM;
455         }
456         init_waitqueue_head(&priv->delta_msr_wait);
457
458         usb_reset_configuration(serial->dev);
459
460         priv->cmd_ctrl = 0;
461         priv->line_control = 0;
462         priv->termios_initialized = 0;
463         priv->rx_flags = 0;
464         /* Default packet format setting is determined by packet size.
465            Anything with a size larger then 9 must have a separate
466            count field since the 3 bit count field is otherwise too
467            small.  Otherwise we can use the slightly more compact
468            format.  This is in accordance with the cypress_m8 serial
469            converter app note. */
470         if (port->interrupt_out_size > 9)
471                 priv->pkt_fmt = packet_format_1;
472         else
473                 priv->pkt_fmt = packet_format_2;
474
475         if (interval > 0) {
476                 priv->write_urb_interval = interval;
477                 priv->read_urb_interval = interval;
478                 dev_dbg(&port->dev, "%s - read & write intervals forced to %d\n",
479                         __func__, interval);
480         } else {
481                 priv->write_urb_interval = port->interrupt_out_urb->interval;
482                 priv->read_urb_interval = port->interrupt_in_urb->interval;
483                 dev_dbg(&port->dev, "%s - intervals: read=%d write=%d\n",
484                         __func__, priv->read_urb_interval,
485                         priv->write_urb_interval);
486         }
487         usb_set_serial_port_data(port, priv);
488
489         return 0;
490 }
491
492
493 static int cypress_earthmate_port_probe(struct usb_serial_port *port)
494 {
495         struct usb_serial *serial = port->serial;
496         struct cypress_private *priv;
497         int ret;
498
499         ret = cypress_generic_port_probe(port);
500         if (ret) {
501                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
502                 return ret;
503         }
504
505         priv = usb_get_serial_port_data(port);
506         priv->chiptype = CT_EARTHMATE;
507         /* All Earthmate devices use the separated-count packet
508            format!  Idiotic. */
509         priv->pkt_fmt = packet_format_1;
510         if (serial->dev->descriptor.idProduct !=
511                                 cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
512                 /* The old original USB Earthmate seemed able to
513                    handle GET_CONFIG requests; everything they've
514                    produced since that time crashes if this command is
515                    attempted :-( */
516                 dev_dbg(&port->dev,
517                         "%s - Marking this device as unsafe for GET_CONFIG commands\n",
518                         __func__);
519                 priv->get_cfg_unsafe = !0;
520         }
521
522         return 0;
523 }
524
525 static int cypress_hidcom_port_probe(struct usb_serial_port *port)
526 {
527         struct cypress_private *priv;
528         int ret;
529
530         ret = cypress_generic_port_probe(port);
531         if (ret) {
532                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
533                 return ret;
534         }
535
536         priv = usb_get_serial_port_data(port);
537         priv->chiptype = CT_CYPHIDCOM;
538
539         return 0;
540 }
541
542 static int cypress_ca42v2_port_probe(struct usb_serial_port *port)
543 {
544         struct cypress_private *priv;
545         int ret;
546
547         ret = cypress_generic_port_probe(port);
548         if (ret) {
549                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
550                 return ret;
551         }
552
553         priv = usb_get_serial_port_data(port);
554         priv->chiptype = CT_CA42V2;
555
556         return 0;
557 }
558
559 static int cypress_port_remove(struct usb_serial_port *port)
560 {
561         struct cypress_private *priv;
562
563         priv = usb_get_serial_port_data(port);
564
565         kfifo_free(&priv->write_fifo);
566         kfree(priv);
567
568         return 0;
569 }
570
571 static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
572 {
573         struct cypress_private *priv = usb_get_serial_port_data(port);
574         struct usb_serial *serial = port->serial;
575         unsigned long flags;
576         int result = 0;
577
578         if (!priv->comm_is_ok)
579                 return -EIO;
580
581         /* clear halts before open */
582         usb_clear_halt(serial->dev, 0x81);
583         usb_clear_halt(serial->dev, 0x02);
584
585         spin_lock_irqsave(&priv->lock, flags);
586         /* reset read/write statistics */
587         priv->bytes_in = 0;
588         priv->bytes_out = 0;
589         priv->cmd_count = 0;
590         priv->rx_flags = 0;
591         spin_unlock_irqrestore(&priv->lock, flags);
592
593         /* Set termios */
594         cypress_send(port);
595
596         if (tty)
597                 cypress_set_termios(tty, port, &priv->tmp_termios);
598
599         /* setup the port and start reading from the device */
600         if (!port->interrupt_in_urb) {
601                 dev_err(&port->dev, "%s - interrupt_in_urb is empty!\n",
602                         __func__);
603                 return -1;
604         }
605
606         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
607                 usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
608                 port->interrupt_in_urb->transfer_buffer,
609                 port->interrupt_in_urb->transfer_buffer_length,
610                 cypress_read_int_callback, port, priv->read_urb_interval);
611         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
612
613         if (result) {
614                 dev_err(&port->dev,
615                         "%s - failed submitting read urb, error %d\n",
616                                                         __func__, result);
617                 cypress_set_dead(port);
618         }
619         port->port.drain_delay = 256;
620         return result;
621 } /* cypress_open */
622
623 static void cypress_dtr_rts(struct usb_serial_port *port, int on)
624 {
625         struct cypress_private *priv = usb_get_serial_port_data(port);
626         /* drop dtr and rts */
627         spin_lock_irq(&priv->lock);
628         if (on == 0)
629                 priv->line_control = 0;
630         else 
631                 priv->line_control = CONTROL_DTR | CONTROL_RTS;
632         priv->cmd_ctrl = 1;
633         spin_unlock_irq(&priv->lock);
634         cypress_write(NULL, port, NULL, 0);
635 }
636
637 static void cypress_close(struct usb_serial_port *port)
638 {
639         struct cypress_private *priv = usb_get_serial_port_data(port);
640         unsigned long flags;
641
642         /* writing is potentially harmful, lock must be taken */
643         mutex_lock(&port->serial->disc_mutex);
644         if (port->serial->disconnected) {
645                 mutex_unlock(&port->serial->disc_mutex);
646                 return;
647         }
648         spin_lock_irqsave(&priv->lock, flags);
649         kfifo_reset_out(&priv->write_fifo);
650         spin_unlock_irqrestore(&priv->lock, flags);
651
652         dev_dbg(&port->dev, "%s - stopping urbs\n", __func__);
653         usb_kill_urb(port->interrupt_in_urb);
654         usb_kill_urb(port->interrupt_out_urb);
655
656         if (stats)
657                 dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
658                         priv->bytes_in, priv->bytes_out, priv->cmd_count);
659         mutex_unlock(&port->serial->disc_mutex);
660 } /* cypress_close */
661
662
663 static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
664                                         const unsigned char *buf, int count)
665 {
666         struct cypress_private *priv = usb_get_serial_port_data(port);
667
668         dev_dbg(&port->dev, "%s - port %d, %d bytes\n", __func__, port->number, count);
669
670         /* line control commands, which need to be executed immediately,
671            are not put into the buffer for obvious reasons.
672          */
673         if (priv->cmd_ctrl) {
674                 count = 0;
675                 goto finish;
676         }
677
678         if (!count)
679                 return count;
680
681         count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
682
683 finish:
684         cypress_send(port);
685
686         return count;
687 } /* cypress_write */
688
689
690 static void cypress_send(struct usb_serial_port *port)
691 {
692         int count = 0, result, offset, actual_size;
693         struct cypress_private *priv = usb_get_serial_port_data(port);
694         struct device *dev = &port->dev;
695         unsigned long flags;
696
697         if (!priv->comm_is_ok)
698                 return;
699
700         dev_dbg(dev, "%s - interrupt out size is %d\n", __func__,
701                 port->interrupt_out_size);
702
703         spin_lock_irqsave(&priv->lock, flags);
704         if (priv->write_urb_in_use) {
705                 dev_dbg(dev, "%s - can't write, urb in use\n", __func__);
706                 spin_unlock_irqrestore(&priv->lock, flags);
707                 return;
708         }
709         spin_unlock_irqrestore(&priv->lock, flags);
710
711         /* clear buffer */
712         memset(port->interrupt_out_urb->transfer_buffer, 0,
713                                                 port->interrupt_out_size);
714
715         spin_lock_irqsave(&priv->lock, flags);
716         switch (priv->pkt_fmt) {
717         default:
718         case packet_format_1:
719                 /* this is for the CY7C64013... */
720                 offset = 2;
721                 port->interrupt_out_buffer[0] = priv->line_control;
722                 break;
723         case packet_format_2:
724                 /* this is for the CY7C63743... */
725                 offset = 1;
726                 port->interrupt_out_buffer[0] = priv->line_control;
727                 break;
728         }
729
730         if (priv->line_control & CONTROL_RESET)
731                 priv->line_control &= ~CONTROL_RESET;
732
733         if (priv->cmd_ctrl) {
734                 priv->cmd_count++;
735                 dev_dbg(dev, "%s - line control command being issued\n", __func__);
736                 spin_unlock_irqrestore(&priv->lock, flags);
737                 goto send;
738         } else
739                 spin_unlock_irqrestore(&priv->lock, flags);
740
741         count = kfifo_out_locked(&priv->write_fifo,
742                                         &port->interrupt_out_buffer[offset],
743                                         port->interrupt_out_size - offset,
744                                         &priv->lock);
745         if (count == 0)
746                 return;
747
748         switch (priv->pkt_fmt) {
749         default:
750         case packet_format_1:
751                 port->interrupt_out_buffer[1] = count;
752                 break;
753         case packet_format_2:
754                 port->interrupt_out_buffer[0] |= count;
755         }
756
757         dev_dbg(dev, "%s - count is %d\n", __func__, count);
758
759 send:
760         spin_lock_irqsave(&priv->lock, flags);
761         priv->write_urb_in_use = 1;
762         spin_unlock_irqrestore(&priv->lock, flags);
763
764         if (priv->cmd_ctrl)
765                 actual_size = 1;
766         else
767                 actual_size = count +
768                               (priv->pkt_fmt == packet_format_1 ? 2 : 1);
769
770         usb_serial_debug_data(dev, __func__, port->interrupt_out_size,
771                               port->interrupt_out_urb->transfer_buffer);
772
773         usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
774                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
775                 port->interrupt_out_buffer, port->interrupt_out_size,
776                 cypress_write_int_callback, port, priv->write_urb_interval);
777         result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
778         if (result) {
779                 dev_err_console(port,
780                                 "%s - failed submitting write urb, error %d\n",
781                                                         __func__, result);
782                 priv->write_urb_in_use = 0;
783                 cypress_set_dead(port);
784         }
785
786         spin_lock_irqsave(&priv->lock, flags);
787         if (priv->cmd_ctrl)
788                 priv->cmd_ctrl = 0;
789
790         /* do not count the line control and size bytes */
791         priv->bytes_out += count;
792         spin_unlock_irqrestore(&priv->lock, flags);
793
794         usb_serial_port_softint(port);
795 } /* cypress_send */
796
797
798 /* returns how much space is available in the soft buffer */
799 static int cypress_write_room(struct tty_struct *tty)
800 {
801         struct usb_serial_port *port = tty->driver_data;
802         struct cypress_private *priv = usb_get_serial_port_data(port);
803         int room = 0;
804         unsigned long flags;
805
806         spin_lock_irqsave(&priv->lock, flags);
807         room = kfifo_avail(&priv->write_fifo);
808         spin_unlock_irqrestore(&priv->lock, flags);
809
810         dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
811         return room;
812 }
813
814
815 static int cypress_tiocmget(struct tty_struct *tty)
816 {
817         struct usb_serial_port *port = tty->driver_data;
818         struct cypress_private *priv = usb_get_serial_port_data(port);
819         __u8 status, control;
820         unsigned int result = 0;
821         unsigned long flags;
822
823         spin_lock_irqsave(&priv->lock, flags);
824         control = priv->line_control;
825         status = priv->current_status;
826         spin_unlock_irqrestore(&priv->lock, flags);
827
828         result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
829                 | ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
830                 | ((status & UART_CTS)        ? TIOCM_CTS : 0)
831                 | ((status & UART_DSR)        ? TIOCM_DSR : 0)
832                 | ((status & UART_RI)         ? TIOCM_RI  : 0)
833                 | ((status & UART_CD)         ? TIOCM_CD  : 0);
834
835         dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
836
837         return result;
838 }
839
840
841 static int cypress_tiocmset(struct tty_struct *tty,
842                                unsigned int set, unsigned int clear)
843 {
844         struct usb_serial_port *port = tty->driver_data;
845         struct cypress_private *priv = usb_get_serial_port_data(port);
846         unsigned long flags;
847
848         spin_lock_irqsave(&priv->lock, flags);
849         if (set & TIOCM_RTS)
850                 priv->line_control |= CONTROL_RTS;
851         if (set & TIOCM_DTR)
852                 priv->line_control |= CONTROL_DTR;
853         if (clear & TIOCM_RTS)
854                 priv->line_control &= ~CONTROL_RTS;
855         if (clear & TIOCM_DTR)
856                 priv->line_control &= ~CONTROL_DTR;
857         priv->cmd_ctrl = 1;
858         spin_unlock_irqrestore(&priv->lock, flags);
859
860         return cypress_write(tty, port, NULL, 0);
861 }
862
863
864 static int cypress_ioctl(struct tty_struct *tty,
865                                         unsigned int cmd, unsigned long arg)
866 {
867         struct usb_serial_port *port = tty->driver_data;
868         struct cypress_private *priv = usb_get_serial_port_data(port);
869
870         dev_dbg(&port->dev, "%s - port %d, cmd 0x%.4x\n", __func__, port->number, cmd);
871
872         switch (cmd) {
873         /* This code comes from drivers/char/serial.c and ftdi_sio.c */
874         case TIOCMIWAIT:
875                 while (priv != NULL) {
876                         interruptible_sleep_on(&priv->delta_msr_wait);
877                         /* see if a signal did it */
878                         if (signal_pending(current))
879                                 return -ERESTARTSYS;
880                         else {
881                                 char diff = priv->diff_status;
882                                 if (diff == 0)
883                                         return -EIO; /* no change => error */
884
885                                 /* consume all events */
886                                 priv->diff_status = 0;
887
888                                 /* return 0 if caller wanted to know about
889                                    these bits */
890                                 if (((arg & TIOCM_RNG) && (diff & UART_RI)) ||
891                                     ((arg & TIOCM_DSR) && (diff & UART_DSR)) ||
892                                     ((arg & TIOCM_CD) && (diff & UART_CD)) ||
893                                     ((arg & TIOCM_CTS) && (diff & UART_CTS)))
894                                         return 0;
895                                 /* otherwise caller can't care less about what
896                                  * happened, and so we continue to wait for
897                                  * more events.
898                                  */
899                         }
900                 }
901                 return 0;
902         default:
903                 break;
904         }
905         dev_dbg(&port->dev, "%s - arg not supported - it was 0x%04x - check include/asm/ioctls.h\n", __func__, cmd);
906         return -ENOIOCTLCMD;
907 } /* cypress_ioctl */
908
909
910 static void cypress_set_termios(struct tty_struct *tty,
911         struct usb_serial_port *port, struct ktermios *old_termios)
912 {
913         struct cypress_private *priv = usb_get_serial_port_data(port);
914         struct device *dev = &port->dev;
915         int data_bits, stop_bits, parity_type, parity_enable;
916         unsigned cflag, iflag;
917         unsigned long flags;
918         __u8 oldlines;
919         int linechange = 0;
920
921         spin_lock_irqsave(&priv->lock, flags);
922         /* We can't clean this one up as we don't know the device type
923            early enough */
924         if (!priv->termios_initialized) {
925                 if (priv->chiptype == CT_EARTHMATE) {
926                         tty->termios = tty_std_termios;
927                         tty->termios.c_cflag = B4800 | CS8 | CREAD | HUPCL |
928                                 CLOCAL;
929                         tty->termios.c_ispeed = 4800;
930                         tty->termios.c_ospeed = 4800;
931                 } else if (priv->chiptype == CT_CYPHIDCOM) {
932                         tty->termios = tty_std_termios;
933                         tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
934                                 CLOCAL;
935                         tty->termios.c_ispeed = 9600;
936                         tty->termios.c_ospeed = 9600;
937                 } else if (priv->chiptype == CT_CA42V2) {
938                         tty->termios = tty_std_termios;
939                         tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
940                                 CLOCAL;
941                         tty->termios.c_ispeed = 9600;
942                         tty->termios.c_ospeed = 9600;
943                 }
944                 priv->termios_initialized = 1;
945         }
946         spin_unlock_irqrestore(&priv->lock, flags);
947
948         /* Unsupported features need clearing */
949         tty->termios.c_cflag &= ~(CMSPAR|CRTSCTS);
950
951         cflag = tty->termios.c_cflag;
952         iflag = tty->termios.c_iflag;
953
954         /* check if there are new settings */
955         if (old_termios) {
956                 spin_lock_irqsave(&priv->lock, flags);
957                 priv->tmp_termios = tty->termios;
958                 spin_unlock_irqrestore(&priv->lock, flags);
959         }
960
961         /* set number of data bits, parity, stop bits */
962         /* when parity is disabled the parity type bit is ignored */
963
964         /* 1 means 2 stop bits, 0 means 1 stop bit */
965         stop_bits = cflag & CSTOPB ? 1 : 0;
966
967         if (cflag & PARENB) {
968                 parity_enable = 1;
969                 /* 1 means odd parity, 0 means even parity */
970                 parity_type = cflag & PARODD ? 1 : 0;
971         } else
972                 parity_enable = parity_type = 0;
973
974         switch (cflag & CSIZE) {
975         case CS5:
976                 data_bits = 0;
977                 break;
978         case CS6:
979                 data_bits = 1;
980                 break;
981         case CS7:
982                 data_bits = 2;
983                 break;
984         case CS8:
985                 data_bits = 3;
986                 break;
987         default:
988                 dev_err(dev, "%s - CSIZE was set, but not CS5-CS8\n", __func__);
989                 data_bits = 3;
990         }
991         spin_lock_irqsave(&priv->lock, flags);
992         oldlines = priv->line_control;
993         if ((cflag & CBAUD) == B0) {
994                 /* drop dtr and rts */
995                 dev_dbg(dev, "%s - dropping the lines, baud rate 0bps\n", __func__);
996                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
997         } else
998                 priv->line_control = (CONTROL_DTR | CONTROL_RTS);
999         spin_unlock_irqrestore(&priv->lock, flags);
1000
1001         dev_dbg(dev, "%s - sending %d stop_bits, %d parity_enable, %d parity_type, %d data_bits (+5)\n",
1002                 __func__, stop_bits, parity_enable, parity_type, data_bits);
1003
1004         cypress_serial_control(tty, port, tty_get_baud_rate(tty),
1005                         data_bits, stop_bits,
1006                         parity_enable, parity_type,
1007                         0, CYPRESS_SET_CONFIG);
1008
1009         /* we perform a CYPRESS_GET_CONFIG so that the current settings are
1010          * filled into the private structure this should confirm that all is
1011          * working if it returns what we just set */
1012         cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
1013
1014         /* Here we can define custom tty settings for devices; the main tty
1015          * termios flag base comes from empeg.c */
1016
1017         spin_lock_irqsave(&priv->lock, flags);
1018         if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
1019                 dev_dbg(dev, "Using custom termios settings for a baud rate of 4800bps.\n");
1020                 /* define custom termios settings for NMEA protocol */
1021
1022                 tty->termios.c_iflag /* input modes - */
1023                         &= ~(IGNBRK  /* disable ignore break */
1024                         | BRKINT     /* disable break causes interrupt */
1025                         | PARMRK     /* disable mark parity errors */
1026                         | ISTRIP     /* disable clear high bit of input char */
1027                         | INLCR      /* disable translate NL to CR */
1028                         | IGNCR      /* disable ignore CR */
1029                         | ICRNL      /* disable translate CR to NL */
1030                         | IXON);     /* disable enable XON/XOFF flow control */
1031
1032                 tty->termios.c_oflag /* output modes */
1033                         &= ~OPOST;    /* disable postprocess output char */
1034
1035                 tty->termios.c_lflag /* line discipline modes */
1036                         &= ~(ECHO     /* disable echo input characters */
1037                         | ECHONL      /* disable echo new line */
1038                         | ICANON      /* disable erase, kill, werase, and rprnt
1039                                          special characters */
1040                         | ISIG        /* disable interrupt, quit, and suspend
1041                                          special characters */
1042                         | IEXTEN);    /* disable non-POSIX special characters */
1043         } /* CT_CYPHIDCOM: Application should handle this for device */
1044
1045         linechange = (priv->line_control != oldlines);
1046         spin_unlock_irqrestore(&priv->lock, flags);
1047
1048         /* if necessary, set lines */
1049         if (linechange) {
1050                 priv->cmd_ctrl = 1;
1051                 cypress_write(tty, port, NULL, 0);
1052         }
1053 } /* cypress_set_termios */
1054
1055
1056 /* returns amount of data still left in soft buffer */
1057 static int cypress_chars_in_buffer(struct tty_struct *tty)
1058 {
1059         struct usb_serial_port *port = tty->driver_data;
1060         struct cypress_private *priv = usb_get_serial_port_data(port);
1061         int chars = 0;
1062         unsigned long flags;
1063
1064         spin_lock_irqsave(&priv->lock, flags);
1065         chars = kfifo_len(&priv->write_fifo);
1066         spin_unlock_irqrestore(&priv->lock, flags);
1067
1068         dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1069         return chars;
1070 }
1071
1072
1073 static void cypress_throttle(struct tty_struct *tty)
1074 {
1075         struct usb_serial_port *port = tty->driver_data;
1076         struct cypress_private *priv = usb_get_serial_port_data(port);
1077
1078         spin_lock_irq(&priv->lock);
1079         priv->rx_flags = THROTTLED;
1080         spin_unlock_irq(&priv->lock);
1081 }
1082
1083
1084 static void cypress_unthrottle(struct tty_struct *tty)
1085 {
1086         struct usb_serial_port *port = tty->driver_data;
1087         struct cypress_private *priv = usb_get_serial_port_data(port);
1088         int actually_throttled, result;
1089
1090         spin_lock_irq(&priv->lock);
1091         actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1092         priv->rx_flags = 0;
1093         spin_unlock_irq(&priv->lock);
1094
1095         if (!priv->comm_is_ok)
1096                 return;
1097
1098         if (actually_throttled) {
1099                 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1100                 if (result) {
1101                         dev_err(&port->dev, "%s - failed submitting read urb, "
1102                                         "error %d\n", __func__, result);
1103                         cypress_set_dead(port);
1104                 }
1105         }
1106 }
1107
1108
1109 static void cypress_read_int_callback(struct urb *urb)
1110 {
1111         struct usb_serial_port *port = urb->context;
1112         struct cypress_private *priv = usb_get_serial_port_data(port);
1113         struct device *dev = &urb->dev->dev;
1114         struct tty_struct *tty;
1115         unsigned char *data = urb->transfer_buffer;
1116         unsigned long flags;
1117         char tty_flag = TTY_NORMAL;
1118         int havedata = 0;
1119         int bytes = 0;
1120         int result;
1121         int i = 0;
1122         int status = urb->status;
1123
1124         switch (status) {
1125         case 0: /* success */
1126                 break;
1127         case -ECONNRESET:
1128         case -ENOENT:
1129         case -ESHUTDOWN:
1130                 /* precursor to disconnect so just go away */
1131                 return;
1132         case -EPIPE:
1133                 /* Can't call usb_clear_halt while in_interrupt */
1134                 /* FALLS THROUGH */
1135         default:
1136                 /* something ugly is going on... */
1137                 dev_err(dev, "%s - unexpected nonzero read status received: %d\n",
1138                         __func__, status);
1139                 cypress_set_dead(port);
1140                 return;
1141         }
1142
1143         spin_lock_irqsave(&priv->lock, flags);
1144         if (priv->rx_flags & THROTTLED) {
1145                 dev_dbg(dev, "%s - now throttling\n", __func__);
1146                 priv->rx_flags |= ACTUALLY_THROTTLED;
1147                 spin_unlock_irqrestore(&priv->lock, flags);
1148                 return;
1149         }
1150         spin_unlock_irqrestore(&priv->lock, flags);
1151
1152         tty = tty_port_tty_get(&port->port);
1153         if (!tty) {
1154                 dev_dbg(dev, "%s - bad tty pointer - exiting\n", __func__);
1155                 return;
1156         }
1157
1158         spin_lock_irqsave(&priv->lock, flags);
1159         result = urb->actual_length;
1160         switch (priv->pkt_fmt) {
1161         default:
1162         case packet_format_1:
1163                 /* This is for the CY7C64013... */
1164                 priv->current_status = data[0] & 0xF8;
1165                 bytes = data[1] + 2;
1166                 i = 2;
1167                 if (bytes > 2)
1168                         havedata = 1;
1169                 break;
1170         case packet_format_2:
1171                 /* This is for the CY7C63743... */
1172                 priv->current_status = data[0] & 0xF8;
1173                 bytes = (data[0] & 0x07) + 1;
1174                 i = 1;
1175                 if (bytes > 1)
1176                         havedata = 1;
1177                 break;
1178         }
1179         spin_unlock_irqrestore(&priv->lock, flags);
1180         if (result < bytes) {
1181                 dev_dbg(dev,
1182                         "%s - wrong packet size - received %d bytes but packet said %d bytes\n",
1183                         __func__, result, bytes);
1184                 goto continue_read;
1185         }
1186
1187         usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1188
1189         spin_lock_irqsave(&priv->lock, flags);
1190         /* check to see if status has changed */
1191         if (priv->current_status != priv->prev_status) {
1192                 priv->diff_status |= priv->current_status ^
1193                         priv->prev_status;
1194                 wake_up_interruptible(&priv->delta_msr_wait);
1195                 priv->prev_status = priv->current_status;
1196         }
1197         spin_unlock_irqrestore(&priv->lock, flags);
1198
1199         /* hangup, as defined in acm.c... this might be a bad place for it
1200          * though */
1201         if (tty && !(tty->termios.c_cflag & CLOCAL) &&
1202                         !(priv->current_status & UART_CD)) {
1203                 dev_dbg(dev, "%s - calling hangup\n", __func__);
1204                 tty_hangup(tty);
1205                 goto continue_read;
1206         }
1207
1208         /* There is one error bit... I'm assuming it is a parity error
1209          * indicator as the generic firmware will set this bit to 1 if a
1210          * parity error occurs.
1211          * I can not find reference to any other error events. */
1212         spin_lock_irqsave(&priv->lock, flags);
1213         if (priv->current_status & CYP_ERROR) {
1214                 spin_unlock_irqrestore(&priv->lock, flags);
1215                 tty_flag = TTY_PARITY;
1216                 dev_dbg(dev, "%s - Parity Error detected\n", __func__);
1217         } else
1218                 spin_unlock_irqrestore(&priv->lock, flags);
1219
1220         /* process read if there is data other than line status */
1221         if (tty && bytes > i) {
1222                 tty_insert_flip_string_fixed_flag(tty, data + i,
1223                                 tty_flag, bytes - i);
1224                 tty_flip_buffer_push(tty);
1225         }
1226
1227         spin_lock_irqsave(&priv->lock, flags);
1228         /* control and status byte(s) are also counted */
1229         priv->bytes_in += bytes;
1230         spin_unlock_irqrestore(&priv->lock, flags);
1231
1232 continue_read:
1233         tty_kref_put(tty);
1234
1235         /* Continue trying to always read */
1236
1237         if (priv->comm_is_ok) {
1238                 usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1239                                 usb_rcvintpipe(port->serial->dev,
1240                                         port->interrupt_in_endpointAddress),
1241                                 port->interrupt_in_urb->transfer_buffer,
1242                                 port->interrupt_in_urb->transfer_buffer_length,
1243                                 cypress_read_int_callback, port,
1244                                 priv->read_urb_interval);
1245                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1246                 if (result && result != -EPERM) {
1247                         dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
1248                                 __func__, result);
1249                         cypress_set_dead(port);
1250                 }
1251         }
1252 } /* cypress_read_int_callback */
1253
1254
1255 static void cypress_write_int_callback(struct urb *urb)
1256 {
1257         struct usb_serial_port *port = urb->context;
1258         struct cypress_private *priv = usb_get_serial_port_data(port);
1259         struct device *dev = &urb->dev->dev;
1260         int result;
1261         int status = urb->status;
1262
1263         switch (status) {
1264         case 0:
1265                 /* success */
1266                 break;
1267         case -ECONNRESET:
1268         case -ENOENT:
1269         case -ESHUTDOWN:
1270                 /* this urb is terminated, clean up */
1271                 dev_dbg(dev, "%s - urb shutting down with status: %d\n",
1272                         __func__, status);
1273                 priv->write_urb_in_use = 0;
1274                 return;
1275         case -EPIPE: /* no break needed; clear halt and resubmit */
1276                 if (!priv->comm_is_ok)
1277                         break;
1278                 usb_clear_halt(port->serial->dev, 0x02);
1279                 /* error in the urb, so we have to resubmit it */
1280                 dev_dbg(dev, "%s - nonzero write bulk status received: %d\n",
1281                         __func__, status);
1282                 port->interrupt_out_urb->transfer_buffer_length = 1;
1283                 result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
1284                 if (!result)
1285                         return;
1286                 dev_err(dev, "%s - failed resubmitting write urb, error %d\n",
1287                         __func__, result);
1288                 cypress_set_dead(port);
1289                 break;
1290         default:
1291                 dev_err(dev, "%s - unexpected nonzero write status received: %d\n",
1292                         __func__, status);
1293                 cypress_set_dead(port);
1294                 break;
1295         }
1296         priv->write_urb_in_use = 0;
1297
1298         /* send any buffered data */
1299         cypress_send(port);
1300 }
1301
1302 module_usb_serial_driver(serial_drivers, id_table_combined);
1303
1304 MODULE_AUTHOR(DRIVER_AUTHOR);
1305 MODULE_DESCRIPTION(DRIVER_DESC);
1306 MODULE_VERSION(DRIVER_VERSION);
1307 MODULE_LICENSE("GPL");
1308
1309 module_param(stats, bool, S_IRUGO | S_IWUSR);
1310 MODULE_PARM_DESC(stats, "Enable statistics or not");
1311 module_param(interval, int, S_IRUGO | S_IWUSR);
1312 MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1313 module_param(unstable_bauds, bool, S_IRUGO | S_IWUSR);
1314 MODULE_PARM_DESC(unstable_bauds, "Allow unstable baud rates");