[PATCH] USB: cypress_m8: add support for the DeLorme Earthmate lt-20
[linux-2.6] / 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 driver
15  *
16  * See http://geocities.com/i0xox0i for information on this driver and the
17  * earthmate usb device.
18  *
19  *  Lonnie Mendez <dignome@gmail.com>
20  *  4-29-2005
21  *      Fixed problem where setting or retreiving the serial config would fail with
22  *      EPIPE.  Removed CRTS toggling so the driver behaves more like other usbserial
23  *      adapters.  Issued new interval of 1ms instead of the default 10ms.  As a
24  *      result, transfer speed has been substantially increased.  From avg. 850bps to
25  *      avg. 3300bps.  initial termios has also been modified.  Cleaned up code and
26  *      formatting issues so it is more readable.  Replaced the C++ style comments.
27  *
28  *  Lonnie Mendez <dignome@gmail.com>
29  *  12-15-2004
30  *      Incorporated write buffering from pl2303 driver.  Fixed bug with line
31  *      handling so both lines are raised in cypress_open. (was dropping rts)
32  *      Various code cleanups made as well along with other misc bug fixes.
33  *
34  *  Lonnie Mendez <dignome@gmail.com>
35  *  04-10-2004
36  *      Driver modified to support dynamic line settings.  Various improvments
37  *      and features.
38  *
39  *  Neil Whelchel
40  *  10-2003
41  *      Driver first released.
42  *
43  */
44
45 /* Thanks to Neil Whelchel for writing the first cypress m8 implementation for linux. */
46 /* Thanks to cypress for providing references for the hid reports. */
47 /* Thanks to Jiang Zhang for providing links and for general help. */
48 /* Code originates and was built up from ftdi_sio, belkin, pl2303 and others. */
49
50
51 #include <linux/config.h>
52 #include <linux/kernel.h>
53 #include <linux/errno.h>
54 #include <linux/init.h>
55 #include <linux/slab.h>
56 #include <linux/tty.h>
57 #include <linux/tty_driver.h>
58 #include <linux/tty_flip.h>
59 #include <linux/module.h>
60 #include <linux/moduleparam.h>
61 #include <linux/spinlock.h>
62 #include <linux/usb.h>
63 #include <linux/serial.h>
64 #include <linux/delay.h>
65 #include <asm/uaccess.h>
66
67 #include "usb-serial.h"
68 #include "cypress_m8.h"
69
70
71 #ifdef CONFIG_USB_SERIAL_DEBUG
72         static int debug = 1;
73 #else
74         static int debug;
75 #endif
76 static int stats;
77 static int interval;
78
79 /*
80  * Version Information
81  */
82 #define DRIVER_VERSION "v1.09"
83 #define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
84 #define DRIVER_DESC "Cypress USB to Serial Driver"
85
86 /* write buffer size defines */
87 #define CYPRESS_BUF_SIZE        1024
88 #define CYPRESS_CLOSING_WAIT    (30*HZ)
89
90 static struct usb_device_id id_table_earthmate [] = {
91         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
92         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
93         { }                                             /* Terminating entry */
94 };
95
96 static struct usb_device_id id_table_cyphidcomrs232 [] = {
97         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
98         { }                                             /* Terminating entry */
99 };
100
101 static struct usb_device_id id_table_combined [] = {
102         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
103         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
104         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
105         { }                                             /* Terminating entry */
106 };
107
108 MODULE_DEVICE_TABLE (usb, id_table_combined);
109
110 static struct usb_driver cypress_driver = {
111         .name =         "cypress",
112         .probe =        usb_serial_probe,
113         .disconnect =   usb_serial_disconnect,
114         .id_table =     id_table_combined,
115 };
116
117 struct cypress_private {
118         spinlock_t lock;                   /* private lock */
119         int chiptype;                      /* identifier of device, for quirks/etc */
120         int bytes_in;                      /* used for statistics */
121         int bytes_out;                     /* used for statistics */
122         int cmd_count;                     /* used for statistics */
123         int cmd_ctrl;                      /* always set this to 1 before issuing a command */
124         struct cypress_buf *buf;           /* write buffer */
125         int write_urb_in_use;              /* write urb in use indicator */
126         int termios_initialized;
127         __u8 line_control;                 /* holds dtr / rts value */
128         __u8 current_status;               /* received from last read - info on dsr,cts,cd,ri,etc */
129         __u8 current_config;               /* stores the current configuration byte */
130         __u8 rx_flags;                     /* throttling - used from whiteheat/ftdi_sio */
131         int baud_rate;                     /* stores current baud rate in integer form */
132         int cbr_mask;                      /* stores current baud rate in masked form */
133         int isthrottled;                   /* if throttled, discard reads */
134         wait_queue_head_t delta_msr_wait;  /* used for TIOCMIWAIT */
135         char prev_status, diff_status;     /* used for TIOCMIWAIT */
136         /* we pass a pointer to this as the arguement sent to cypress_set_termios old_termios */
137         struct termios tmp_termios;        /* stores the old termios settings */
138 };
139
140 /* write buffer structure */
141 struct cypress_buf {
142         unsigned int    buf_size;
143         char            *buf_buf;
144         char            *buf_get;
145         char            *buf_put;
146 };
147
148 /* function prototypes for the Cypress USB to serial device */
149 static int  cypress_earthmate_startup   (struct usb_serial *serial);
150 static int  cypress_hidcom_startup      (struct usb_serial *serial);
151 static void cypress_shutdown            (struct usb_serial *serial);
152 static int  cypress_open                (struct usb_serial_port *port, struct file *filp);
153 static void cypress_close               (struct usb_serial_port *port, struct file *filp);
154 static int  cypress_write               (struct usb_serial_port *port, const unsigned char *buf, int count);
155 static void cypress_send                (struct usb_serial_port *port);
156 static int  cypress_write_room          (struct usb_serial_port *port);
157 static int  cypress_ioctl               (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
158 static void cypress_set_termios         (struct usb_serial_port *port, struct termios * old);
159 static int  cypress_tiocmget            (struct usb_serial_port *port, struct file *file);
160 static int  cypress_tiocmset            (struct usb_serial_port *port, struct file *file, unsigned int set, unsigned int clear);
161 static int  cypress_chars_in_buffer     (struct usb_serial_port *port);
162 static void cypress_throttle            (struct usb_serial_port *port);
163 static void cypress_unthrottle          (struct usb_serial_port *port);
164 static void cypress_read_int_callback   (struct urb *urb, struct pt_regs *regs);
165 static void cypress_write_int_callback  (struct urb *urb, struct pt_regs *regs);
166 /* baud helper functions */
167 static int       mask_to_rate           (unsigned mask);
168 static unsigned  rate_to_mask           (int rate);
169 /* write buffer functions */
170 static struct cypress_buf *cypress_buf_alloc(unsigned int size);
171 static void               cypress_buf_free(struct cypress_buf *cb);
172 static void               cypress_buf_clear(struct cypress_buf *cb);
173 static unsigned int       cypress_buf_data_avail(struct cypress_buf *cb);
174 static unsigned int       cypress_buf_space_avail(struct cypress_buf *cb);
175 static unsigned int       cypress_buf_put(struct cypress_buf *cb, const char *buf, unsigned int count);
176 static unsigned int       cypress_buf_get(struct cypress_buf *cb, char *buf, unsigned int count);
177
178
179 static struct usb_serial_device_type cypress_earthmate_device = {
180         .owner =                        THIS_MODULE,
181         .name =                         "DeLorme Earthmate USB",
182         .short_name =                   "earthmate",
183         .id_table =                     id_table_earthmate,
184         .num_interrupt_in =             1,
185         .num_interrupt_out =            1,
186         .num_bulk_in =                  NUM_DONT_CARE,
187         .num_bulk_out =                 NUM_DONT_CARE,
188         .num_ports =                    1,
189         .attach =                       cypress_earthmate_startup,
190         .shutdown =                     cypress_shutdown,
191         .open =                         cypress_open,
192         .close =                        cypress_close,
193         .write =                        cypress_write,
194         .write_room =                   cypress_write_room,
195         .ioctl =                        cypress_ioctl,
196         .set_termios =                  cypress_set_termios,
197         .tiocmget =                     cypress_tiocmget,
198         .tiocmset =                     cypress_tiocmset,
199         .chars_in_buffer =              cypress_chars_in_buffer,
200         .throttle =                     cypress_throttle,
201         .unthrottle =                   cypress_unthrottle,
202         .read_int_callback =            cypress_read_int_callback,
203         .write_int_callback =           cypress_write_int_callback,
204 };
205
206 static struct usb_serial_device_type cypress_hidcom_device = {
207         .owner =                        THIS_MODULE,
208         .name =                         "HID->COM RS232 Adapter",
209         .short_name =                   "cyphidcom",
210         .id_table =                     id_table_cyphidcomrs232,
211         .num_interrupt_in =             1,
212         .num_interrupt_out =            1,
213         .num_bulk_in =                  NUM_DONT_CARE,
214         .num_bulk_out =                 NUM_DONT_CARE,
215         .num_ports =                    1,
216         .attach =                       cypress_hidcom_startup,
217         .shutdown =                     cypress_shutdown,
218         .open =                         cypress_open,
219         .close =                        cypress_close,
220         .write =                        cypress_write,
221         .write_room =                   cypress_write_room,
222         .ioctl =                        cypress_ioctl,
223         .set_termios =                  cypress_set_termios,
224         .tiocmget =                     cypress_tiocmget,
225         .tiocmset =                     cypress_tiocmset,
226         .chars_in_buffer =              cypress_chars_in_buffer,
227         .throttle =                     cypress_throttle,
228         .unthrottle =                   cypress_unthrottle,
229         .read_int_callback =            cypress_read_int_callback,
230         .write_int_callback =           cypress_write_int_callback,
231 };
232
233
234 /*****************************************************************************
235  * Cypress serial helper functions
236  *****************************************************************************/
237
238
239 /* This function can either set or retrieve the current serial line settings */
240 static int cypress_serial_control (struct usb_serial_port *port, unsigned baud_mask, int data_bits, int stop_bits,
241                                    int parity_enable, int parity_type, int reset, int cypress_request_type)
242 {
243         int new_baudrate = 0, retval = 0, tries = 0;
244         struct cypress_private *priv;
245         __u8 feature_buffer[8];
246         unsigned long flags;
247
248         dbg("%s", __FUNCTION__);
249         
250         priv = usb_get_serial_port_data(port);
251
252         switch(cypress_request_type) {
253                 case CYPRESS_SET_CONFIG:
254
255                         /*
256                          * The general purpose firmware for the Cypress M8 allows for a maximum speed
257                          * of 57600bps (I have no idea whether DeLorme chose to use the general purpose
258                          * firmware or not), if you need to modify this speed setting for your own
259                          * project please add your own chiptype and modify the code likewise.  The
260                          * Cypress HID->COM device will work successfully up to 115200bps (but the
261                          * actual throughput is around 3kBps).
262                          */
263                         if (baud_mask != priv->cbr_mask) {
264                                 dbg("%s - baud rate is changing", __FUNCTION__);
265                                 if ( priv->chiptype == CT_EARTHMATE ) {
266                                         /* 300 and 600 baud rates are supported under the generic firmware,
267                                          * but are not used with NMEA and SiRF protocols */
268                                         
269                                         if ( (baud_mask == B300) || (baud_mask == B600) ) {
270                                                 err("%s - failed setting baud rate, unsupported speed",
271                                                     __FUNCTION__);
272                                                 new_baudrate = priv->baud_rate;
273                                         } else if ( (new_baudrate = mask_to_rate(baud_mask)) == -1) {
274                                                 err("%s - failed setting baud rate, unsupported speed",
275                                                     __FUNCTION__);
276                                                 new_baudrate = priv->baud_rate;
277                                         }
278                                 } else if (priv->chiptype == CT_CYPHIDCOM) {
279                                         if ( (new_baudrate = mask_to_rate(baud_mask)) == -1) {
280                                                 err("%s - failed setting baud rate, unsupported speed",
281                                                     __FUNCTION__);
282                                                 new_baudrate = priv->baud_rate;
283                                         }
284                                 } else if (priv->chiptype == CT_GENERIC) {
285                                         if ( (new_baudrate = mask_to_rate(baud_mask)) == -1) {
286                                                 err("%s - failed setting baud rate, unsupported speed",
287                                                     __FUNCTION__);
288                                                 new_baudrate = priv->baud_rate;
289                                         }
290                                 } else {
291                                         info("%s - please define your chiptype", __FUNCTION__);
292                                         new_baudrate = priv->baud_rate;
293                                 }
294                         } else {  /* baud rate not changing, keep the old */
295                                 new_baudrate = priv->baud_rate;
296                         }
297                         dbg("%s - baud rate is being sent as %d", __FUNCTION__, new_baudrate);
298                         
299                         memset(feature_buffer, 0, 8);
300                         /* fill the feature_buffer with new configuration */
301                         *((u_int32_t *)feature_buffer) = new_baudrate;
302
303                         feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
304                         /* 1 bit gap */
305                         feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
306                         feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
307                         feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
308                         /* 1 bit gap */
309                         feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
310                                 
311                         dbg("%s - device is being sent this feature report:", __FUNCTION__);
312                         dbg("%s - %02X - %02X - %02X - %02X - %02X", __FUNCTION__, feature_buffer[0], feature_buffer[1],
313                             feature_buffer[2], feature_buffer[3], feature_buffer[4]);
314                         
315                         do {
316                         retval = usb_control_msg (port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
317                                                   HID_REQ_SET_REPORT, USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
318                                                           0x0300, 0, feature_buffer, 8, 500);
319
320                                 if (tries++ >= 3)
321                                         break;
322
323                                 if (retval == EPIPE)
324                                         usb_clear_halt(port->serial->dev, 0x00);
325                         } while (retval != 8 && retval != ENODEV);
326
327                         if (retval != 8)
328                                 err("%s - failed sending serial line settings - %d", __FUNCTION__, retval);
329                         else {
330                                 spin_lock_irqsave(&priv->lock, flags);
331                                 priv->baud_rate = new_baudrate;
332                                 priv->cbr_mask = baud_mask;
333                                 priv->current_config = feature_buffer[4];
334                                 spin_unlock_irqrestore(&priv->lock, flags);
335                         }
336                 break;
337                 case CYPRESS_GET_CONFIG:
338                         dbg("%s - retreiving serial line settings", __FUNCTION__);
339                         /* set initial values in feature buffer */
340                         memset(feature_buffer, 0, 8);
341
342                         do {
343                         retval = usb_control_msg (port->serial->dev, usb_rcvctrlpipe(port->serial->dev, 0),
344                                                   HID_REQ_GET_REPORT, USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
345                                                           0x0300, 0, feature_buffer, 8, 500);
346                                 
347                                 if (tries++ >= 3)
348                                         break;
349
350                                 if (retval == EPIPE)
351                                         usb_clear_halt(port->serial->dev, 0x00);
352                         } while (retval != 5 && retval != ENODEV);
353
354                         if (retval != 5) {
355                                 err("%s - failed to retreive serial line settings - %d", __FUNCTION__, retval);
356                                 return retval;
357                         } else {
358                                 spin_lock_irqsave(&priv->lock, flags);
359
360                                 /* store the config in one byte, and later use bit masks to check values */
361                                 priv->current_config = feature_buffer[4];
362                                 priv->baud_rate = *((u_int32_t *)feature_buffer);
363                                 
364                                 if ( (priv->cbr_mask = rate_to_mask(priv->baud_rate)) == 0x40)
365                                         dbg("%s - failed setting the baud mask (not defined)", __FUNCTION__);
366                                 spin_unlock_irqrestore(&priv->lock, flags);
367                         }
368         }
369         spin_lock_irqsave(&priv->lock, flags);
370         ++priv->cmd_count;
371         spin_unlock_irqrestore(&priv->lock, flags);
372
373         return retval;
374 } /* cypress_serial_control */
375
376
377 /* given a baud mask, it will return integer baud on success */
378 static int mask_to_rate (unsigned mask)
379 {
380         int rate;
381
382         switch (mask) {
383                 case B0: rate = 0; break;
384                 case B300: rate = 300; break;
385                 case B600: rate = 600; break;
386                 case B1200: rate = 1200; break;
387                 case B2400: rate = 2400; break;
388                 case B4800: rate = 4800; break;
389                 case B9600: rate = 9600; break;
390                 case B19200: rate = 19200; break;
391                 case B38400: rate = 38400; break;
392                 case B57600: rate = 57600; break;
393                 case B115200: rate = 115200; break;
394                 default: rate = -1;
395         }
396
397         return rate;
398 }
399
400
401 static unsigned rate_to_mask (int rate)
402 {
403         unsigned mask;
404
405         switch (rate) {
406                 case 0: mask = B0; break;
407                 case 300: mask = B300; break;
408                 case 600: mask = B600; break;
409                 case 1200: mask = B1200; break;
410                 case 2400: mask = B2400; break;
411                 case 4800: mask = B4800; break;
412                 case 9600: mask = B9600; break;
413                 case 19200: mask = B19200; break;
414                 case 38400: mask = B38400; break;
415                 case 57600: mask = B57600; break;
416                 case 115200: mask = B115200; break;
417                 default: mask = 0x40;
418         }
419
420         return mask;
421 }
422 /*****************************************************************************
423  * Cypress serial driver functions
424  *****************************************************************************/
425
426
427 static int generic_startup (struct usb_serial *serial)
428 {
429         struct cypress_private *priv;
430
431         dbg("%s - port %d", __FUNCTION__, serial->port[0]->number);
432
433         priv = kmalloc(sizeof (struct cypress_private), GFP_KERNEL);
434         if (!priv)
435                 return -ENOMEM;
436
437         memset(priv, 0x00, sizeof (struct cypress_private));
438         spin_lock_init(&priv->lock);
439         priv->buf = cypress_buf_alloc(CYPRESS_BUF_SIZE);
440         if (priv->buf == NULL) {
441                 kfree(priv);
442                 return -ENOMEM;
443         }
444         init_waitqueue_head(&priv->delta_msr_wait);
445         
446         usb_reset_configuration (serial->dev);
447         
448         interval = 1;
449         priv->cmd_ctrl = 0;
450         priv->line_control = 0;
451         priv->termios_initialized = 0;
452         priv->rx_flags = 0;
453         priv->cbr_mask = B300;
454         usb_set_serial_port_data(serial->port[0], priv);
455         
456         return (0);     
457 }       
458
459
460 static int cypress_earthmate_startup (struct usb_serial *serial)
461 {
462         struct cypress_private *priv;
463
464         dbg("%s", __FUNCTION__);
465
466         if (generic_startup(serial)) {
467                 dbg("%s - Failed setting up port %d", __FUNCTION__, serial->port[0]->number);
468                 return 1;
469         }
470
471         priv = usb_get_serial_port_data(serial->port[0]);
472         priv->chiptype = CT_EARTHMATE;
473         
474         return (0);     
475 } /* cypress_earthmate_startup */
476
477
478 static int cypress_hidcom_startup (struct usb_serial *serial)
479 {
480         struct cypress_private *priv;
481
482         dbg("%s", __FUNCTION__);
483
484         if (generic_startup(serial)) {
485                 dbg("%s - Failed setting up port %d", __FUNCTION__, serial->port[0]->number);
486                 return 1;
487         }
488
489         priv = usb_get_serial_port_data(serial->port[0]);
490         priv->chiptype = CT_CYPHIDCOM;
491         
492         return (0);     
493 } /* cypress_hidcom_startup */
494
495
496 static void cypress_shutdown (struct usb_serial *serial)
497 {
498         struct cypress_private *priv;
499
500         dbg ("%s - port %d", __FUNCTION__, serial->port[0]->number);
501
502         /* all open ports are closed at this point */
503
504         priv = usb_get_serial_port_data(serial->port[0]);
505
506         if (priv) {
507                 cypress_buf_free(priv->buf);
508                 kfree(priv);
509                 usb_set_serial_port_data(serial->port[0], NULL);
510         }
511 }
512
513
514 static int cypress_open (struct usb_serial_port *port, struct file *filp)
515 {
516         struct cypress_private *priv = usb_get_serial_port_data(port);
517         struct usb_serial *serial = port->serial;
518         unsigned long flags;
519         int result = 0;
520
521         dbg("%s - port %d", __FUNCTION__, port->number);
522
523         /* clear halts before open */
524         usb_clear_halt(serial->dev, 0x81);
525         usb_clear_halt(serial->dev, 0x02);
526
527         spin_lock_irqsave(&priv->lock, flags);
528         /* reset read/write statistics */
529         priv->bytes_in = 0;
530         priv->bytes_out = 0;
531         priv->cmd_count = 0;
532         priv->rx_flags = 0;
533         spin_unlock_irqrestore(&priv->lock, flags);
534
535         /* setting to zero could cause data loss */
536         port->tty->low_latency = 1;
537
538         /* raise both lines and set termios */
539         spin_lock_irqsave(&priv->lock, flags);
540         priv->line_control = CONTROL_DTR | CONTROL_RTS;
541         priv->cmd_ctrl = 1;
542         spin_unlock_irqrestore(&priv->lock, flags);
543         result = cypress_write(port, NULL, 0);
544
545         if (result) {
546                 dev_err(&port->dev, "%s - failed setting the control lines - error %d\n", __FUNCTION__, result);
547                 return result;
548         } else
549                 dbg("%s - success setting the control lines", __FUNCTION__);    
550
551         cypress_set_termios(port, &priv->tmp_termios);
552
553         /* setup the port and start reading from the device */
554         if(!port->interrupt_in_urb){
555                 err("%s - interrupt_in_urb is empty!", __FUNCTION__);
556                 return(-1);
557         }
558
559         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
560                 usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
561                 port->interrupt_in_urb->transfer_buffer, port->interrupt_in_urb->transfer_buffer_length,
562                 cypress_read_int_callback, port, interval);
563         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
564
565         if (result){
566                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
567         }
568
569         return result;
570 } /* cypress_open */
571
572
573 static void cypress_close(struct usb_serial_port *port, struct file * filp)
574 {
575         struct cypress_private *priv = usb_get_serial_port_data(port);
576         unsigned int c_cflag;
577         unsigned long flags;
578         int bps;
579         long timeout;
580         wait_queue_t wait;
581
582         dbg("%s - port %d", __FUNCTION__, port->number);
583
584         /* wait for data to drain from buffer */
585         spin_lock_irqsave(&priv->lock, flags);
586         timeout = CYPRESS_CLOSING_WAIT;
587         init_waitqueue_entry(&wait, current);
588         add_wait_queue(&port->tty->write_wait, &wait);
589         for (;;) {
590                 set_current_state(TASK_INTERRUPTIBLE);
591                 if (cypress_buf_data_avail(priv->buf) == 0
592                 || timeout == 0 || signal_pending(current)
593                 || !usb_get_intfdata(port->serial->interface))
594                         break;
595                 spin_unlock_irqrestore(&priv->lock, flags);
596                 timeout = schedule_timeout(timeout);
597                 spin_lock_irqsave(&priv->lock, flags);
598         }
599         set_current_state(TASK_RUNNING);
600         remove_wait_queue(&port->tty->write_wait, &wait);
601         /* clear out any remaining data in the buffer */
602         cypress_buf_clear(priv->buf);
603         spin_unlock_irqrestore(&priv->lock, flags);
604         
605         /* wait for characters to drain from device */
606         bps = tty_get_baud_rate(port->tty);
607         if (bps > 1200)
608                 timeout = max((HZ*2560)/bps,HZ/10);
609         else
610                 timeout = 2*HZ;
611         set_current_state(TASK_INTERRUPTIBLE);
612         schedule_timeout(timeout);
613
614         dbg("%s - stopping urbs", __FUNCTION__);
615         usb_kill_urb (port->interrupt_in_urb);
616         usb_kill_urb (port->interrupt_out_urb);
617
618         if (port->tty) {
619                 c_cflag = port->tty->termios->c_cflag;
620                 if (c_cflag & HUPCL) {
621                         /* drop dtr and rts */
622                         priv = usb_get_serial_port_data(port);
623                         spin_lock_irqsave(&priv->lock, flags);
624                         priv->line_control = 0;
625                         priv->cmd_ctrl = 1;
626                         spin_unlock_irqrestore(&priv->lock, flags);
627                         cypress_write(port, NULL, 0);
628                 }
629         }
630
631         if (stats)
632                 dev_info (&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
633                           priv->bytes_in, priv->bytes_out, priv->cmd_count);
634 } /* cypress_close */
635
636
637 static int cypress_write(struct usb_serial_port *port, const unsigned char *buf, int count)
638 {
639         struct cypress_private *priv = usb_get_serial_port_data(port);
640         unsigned long flags;
641         
642         dbg("%s - port %d, %d bytes", __FUNCTION__, port->number, count);
643
644         /* line control commands, which need to be executed immediately,
645            are not put into the buffer for obvious reasons.
646          */
647         if (priv->cmd_ctrl) {
648                 count = 0;
649                 goto finish;
650         }
651         
652         if (!count)
653                 return count;
654         
655         spin_lock_irqsave(&priv->lock, flags);
656         count = cypress_buf_put(priv->buf, buf, count);
657         spin_unlock_irqrestore(&priv->lock, flags);
658
659 finish:
660         cypress_send(port);
661
662         return count;
663 } /* cypress_write */
664
665
666 static void cypress_send(struct usb_serial_port *port)
667 {
668         int count = 0, result, offset, actual_size;
669         struct cypress_private *priv = usb_get_serial_port_data(port);
670         unsigned long flags;
671         
672         dbg("%s - port %d", __FUNCTION__, port->number);
673         dbg("%s - interrupt out size is %d", __FUNCTION__, port->interrupt_out_size);
674         
675         spin_lock_irqsave(&priv->lock, flags);
676         if (priv->write_urb_in_use) {
677                 dbg("%s - can't write, urb in use", __FUNCTION__);
678                 spin_unlock_irqrestore(&priv->lock, flags);
679                 return;
680         }
681         spin_unlock_irqrestore(&priv->lock, flags);
682
683         /* clear buffer */
684         memset(port->interrupt_out_urb->transfer_buffer, 0, port->interrupt_out_size);
685
686         spin_lock_irqsave(&priv->lock, flags);
687         switch (port->interrupt_out_size) {
688                 case 32:
689                         /* this is for the CY7C64013... */
690                         offset = 2;
691                         port->interrupt_out_buffer[0] = priv->line_control;
692                         break;
693                 case 8:
694                         /* this is for the CY7C63743... */
695                         offset = 1;
696                         port->interrupt_out_buffer[0] = priv->line_control;
697                         break;
698                 default:
699                         dbg("%s - wrong packet size", __FUNCTION__);
700                         spin_unlock_irqrestore(&priv->lock, flags);
701                         return;
702         }
703
704         if (priv->line_control & CONTROL_RESET)
705                 priv->line_control &= ~CONTROL_RESET;
706
707         if (priv->cmd_ctrl) {
708                 priv->cmd_count++;
709                 dbg("%s - line control command being issued", __FUNCTION__);
710                 spin_unlock_irqrestore(&priv->lock, flags);
711                 goto send;
712         } else
713                 spin_unlock_irqrestore(&priv->lock, flags);
714
715         count = cypress_buf_get(priv->buf, &port->interrupt_out_buffer[offset],
716                                 port->interrupt_out_size-offset);
717
718         if (count == 0) {
719                 return;
720         }
721
722         switch (port->interrupt_out_size) {
723                 case 32:
724                         port->interrupt_out_buffer[1] = count;
725                         break;
726                 case 8:
727                         port->interrupt_out_buffer[0] |= count;
728         }
729
730         dbg("%s - count is %d", __FUNCTION__, count);
731
732 send:
733         spin_lock_irqsave(&priv->lock, flags);
734         priv->write_urb_in_use = 1;
735         spin_unlock_irqrestore(&priv->lock, flags);
736
737         if (priv->cmd_ctrl)
738                 actual_size = 1;
739         else
740                 actual_size = count + (port->interrupt_out_size == 32 ? 2 : 1);
741         
742         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, port->interrupt_out_size,
743                               port->interrupt_out_urb->transfer_buffer);
744
745         port->interrupt_out_urb->transfer_buffer_length = actual_size;
746         port->interrupt_out_urb->dev = port->serial->dev;
747         port->interrupt_out_urb->interval = interval;
748         result = usb_submit_urb (port->interrupt_out_urb, GFP_ATOMIC);
749         if (result) {
750                 dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__,
751                         result);
752                 priv->write_urb_in_use = 0;
753         }
754
755         spin_lock_irqsave(&priv->lock, flags);
756         if (priv->cmd_ctrl) {
757                 priv->cmd_ctrl = 0;
758         }
759         priv->bytes_out += count; /* do not count the line control and size bytes */
760         spin_unlock_irqrestore(&priv->lock, flags);
761
762         schedule_work(&port->work);
763 } /* cypress_send */
764
765
766 /* returns how much space is available in the soft buffer */
767 static int cypress_write_room(struct usb_serial_port *port)
768 {
769         struct cypress_private *priv = usb_get_serial_port_data(port);
770         int room = 0;
771         unsigned long flags;
772
773         dbg("%s - port %d", __FUNCTION__, port->number);
774
775         spin_lock_irqsave(&priv->lock, flags);
776         room = cypress_buf_space_avail(priv->buf);
777         spin_unlock_irqrestore(&priv->lock, flags);
778
779         dbg("%s - returns %d", __FUNCTION__, room);
780         return room;
781 }
782
783
784 static int cypress_tiocmget (struct usb_serial_port *port, struct file *file)
785 {
786         struct cypress_private *priv = usb_get_serial_port_data(port);
787         __u8 status, control;
788         unsigned int result = 0;
789         unsigned long flags;
790         
791         dbg("%s - port %d", __FUNCTION__, port->number);
792
793         spin_lock_irqsave(&priv->lock, flags);
794         control = priv->line_control;
795         status = priv->current_status;
796         spin_unlock_irqrestore(&priv->lock, flags);
797
798         result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
799                 | ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
800                 | ((status & UART_CTS)        ? TIOCM_CTS : 0)
801                 | ((status & UART_DSR)        ? TIOCM_DSR : 0)
802                 | ((status & UART_RI)         ? TIOCM_RI  : 0)
803                 | ((status & UART_CD)         ? TIOCM_CD  : 0);
804
805         dbg("%s - result = %x", __FUNCTION__, result);
806
807         return result;
808 }
809
810
811 static int cypress_tiocmset (struct usb_serial_port *port, struct file *file,
812                                unsigned int set, unsigned int clear)
813 {
814         struct cypress_private *priv = usb_get_serial_port_data(port);
815         unsigned long flags;
816         
817         dbg("%s - port %d", __FUNCTION__, port->number);
818
819         spin_lock_irqsave(&priv->lock, flags);
820         if (set & TIOCM_RTS)
821                 priv->line_control |= CONTROL_RTS;
822         if (set & TIOCM_DTR)
823                 priv->line_control |= CONTROL_DTR;
824         if (clear & TIOCM_RTS)
825                 priv->line_control &= ~CONTROL_RTS;
826         if (clear & TIOCM_DTR)
827                 priv->line_control &= ~CONTROL_DTR;
828         spin_unlock_irqrestore(&priv->lock, flags);
829
830         priv->cmd_ctrl = 1;
831         return cypress_write(port, NULL, 0);
832 }
833
834
835 static int cypress_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
836 {
837         struct cypress_private *priv = usb_get_serial_port_data(port);
838
839         dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);
840
841         switch (cmd) {
842                 case TIOCGSERIAL:
843                         if (copy_to_user((void __user *)arg, port->tty->termios, sizeof(struct termios))) {
844                                 return -EFAULT;
845                         }
846                         return (0);
847                         break;
848                 case TIOCSSERIAL:
849                         if (copy_from_user(port->tty->termios, (void __user *)arg, sizeof(struct termios))) {
850                                 return -EFAULT;
851                         }
852                         /* here we need to call cypress_set_termios to invoke the new settings */
853                         cypress_set_termios(port, &priv->tmp_termios);
854                         return (0);
855                         break;
856                 /* these are called when setting baud rate from gpsd */
857                 case TCGETS:
858                         if (copy_to_user((void __user *)arg, port->tty->termios, sizeof(struct termios))) {
859                                 return -EFAULT;
860                         }
861                         return (0);
862                         break;
863                 case TCSETS:
864                         if (copy_from_user(port->tty->termios, (void __user *)arg, sizeof(struct termios))) {
865                                 return -EFAULT;
866                         }
867                         /* here we need to call cypress_set_termios to invoke the new settings */
868                         cypress_set_termios(port, &priv->tmp_termios);
869                         return (0);
870                         break;
871                 /* This code comes from drivers/char/serial.c and ftdi_sio.c */
872                 case TIOCMIWAIT:
873                         while (priv != NULL) {
874                                 interruptible_sleep_on(&priv->delta_msr_wait);
875                                 /* see if a signal did it */
876                                 if (signal_pending(current))
877                                         return -ERESTARTSYS;
878                                 else {
879                                         char diff = priv->diff_status;
880
881                                         if (diff == 0) {
882                                                 return -EIO; /* no change => error */
883                                         }
884                                         
885                                         /* consume all events */
886                                         priv->diff_status = 0;
887
888                                         /* return 0 if caller wanted to know about these bits */
889                                         if ( ((arg & TIOCM_RNG) && (diff & UART_RI)) ||
890                                              ((arg & TIOCM_DSR) && (diff & UART_DSR)) ||
891                                              ((arg & TIOCM_CD) && (diff & UART_CD)) ||
892                                              ((arg & TIOCM_CTS) && (diff & UART_CTS)) ) {
893                                                 return 0;
894                                         }
895                                         /* otherwise caller can't care less about what happened,
896                                          * and so we continue to wait for more events.
897                                          */
898                                 }
899                         }
900                         return 0;
901                         break;
902                 default:
903                         break;
904         }
905
906         dbg("%s - arg not supported - it was 0x%04x - check include/asm/ioctls.h", __FUNCTION__, cmd);
907
908         return -ENOIOCTLCMD;
909 } /* cypress_ioctl */
910
911
912 static void cypress_set_termios (struct usb_serial_port *port, struct termios *old_termios)
913 {
914         struct cypress_private *priv = usb_get_serial_port_data(port);
915         struct tty_struct *tty;
916         int data_bits, stop_bits, parity_type, parity_enable;
917         unsigned cflag, iflag, baud_mask;
918         unsigned long flags;
919         __u8 oldlines;
920         int linechange = 0;
921         
922         dbg("%s - port %d", __FUNCTION__, port->number);
923
924         tty = port->tty;
925         if ((!tty) || (!tty->termios)) {
926                 dbg("%s - no tty structures", __FUNCTION__);
927                 return;
928         }
929
930         spin_lock_irqsave(&priv->lock, flags);
931         if (!priv->termios_initialized) {
932                 if (priv->chiptype == CT_EARTHMATE) {
933                         *(tty->termios) = tty_std_termios;
934                         tty->termios->c_cflag = B4800 | CS8 | CREAD | HUPCL | CLOCAL;
935                 } else if (priv->chiptype == CT_CYPHIDCOM) {
936                         *(tty->termios) = tty_std_termios;
937                         tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
938                 }
939                 priv->termios_initialized = 1;
940         }
941         spin_unlock_irqrestore(&priv->lock, flags);
942
943         cflag = tty->termios->c_cflag;
944         iflag = tty->termios->c_iflag;
945
946         /* check if there are new settings */
947         if (old_termios) {
948                 if ((cflag != old_termios->c_cflag) ||
949                     (RELEVANT_IFLAG(iflag) != RELEVANT_IFLAG(old_termios->c_iflag))) {
950                         dbg("%s - attempting to set new termios settings", __FUNCTION__);
951                         /* should make a copy of this in case something goes wrong in the function, we can restore it */
952                         spin_lock_irqsave(&priv->lock, flags);
953                         priv->tmp_termios = *(tty->termios);
954                         spin_unlock_irqrestore(&priv->lock, flags); 
955                 } else {
956                         dbg("%s - nothing to do, exiting", __FUNCTION__);
957                         return;
958                 }
959         } else
960                 return;
961
962         /* set number of data bits, parity, stop bits */
963         /* when parity is disabled the parity type bit is ignored */
964
965         stop_bits = cflag & CSTOPB ? 1 : 0; /* 1 means 2 stop bits, 0 means 1 stop bit */
966         
967         if (cflag & PARENB) {
968                 parity_enable = 1;
969                 parity_type = cflag & PARODD ? 1 : 0; /* 1 means odd parity, 0 means even parity */
970         } else
971                 parity_enable = parity_type = 0;
972
973         if (cflag & CSIZE) {
974                 switch (cflag & CSIZE) {
975                         case CS5: data_bits = 0; break;
976                         case CS6: data_bits = 1; break;
977                         case CS7: data_bits = 2; break;
978                         case CS8: data_bits = 3; break;
979                         default: err("%s - CSIZE was set, but not CS5-CS8", __FUNCTION__); data_bits = 3;
980                 }
981         } else
982                 data_bits = 3;
983
984         spin_lock_irqsave(&priv->lock, flags);
985         oldlines = priv->line_control;
986         if ((cflag & CBAUD) == B0) {
987                 /* drop dtr and rts */
988                 dbg("%s - dropping the lines, baud rate 0bps", __FUNCTION__);
989                 baud_mask = B0;
990                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
991         } else {
992                 baud_mask = (cflag & CBAUD);
993                 switch(baud_mask) {
994                         case B300: dbg("%s - setting baud 300bps", __FUNCTION__); break;
995                         case B600: dbg("%s - setting baud 600bps", __FUNCTION__); break;
996                         case B1200: dbg("%s - setting baud 1200bps", __FUNCTION__); break;
997                         case B2400: dbg("%s - setting baud 2400bps", __FUNCTION__); break;
998                         case B4800: dbg("%s - setting baud 4800bps", __FUNCTION__); break;
999                         case B9600: dbg("%s - setting baud 9600bps", __FUNCTION__); break;
1000                         case B19200: dbg("%s - setting baud 19200bps", __FUNCTION__); break;
1001                         case B38400: dbg("%s - setting baud 38400bps", __FUNCTION__); break;
1002                         case B57600: dbg("%s - setting baud 57600bps", __FUNCTION__); break;
1003                         case B115200: dbg("%s - setting baud 115200bps", __FUNCTION__); break;
1004                         default: dbg("%s - unknown masked baud rate", __FUNCTION__);
1005                 }
1006                 priv->line_control = (CONTROL_DTR | CONTROL_RTS);
1007         }
1008         spin_unlock_irqrestore(&priv->lock, flags);
1009         
1010         dbg("%s - sending %d stop_bits, %d parity_enable, %d parity_type, %d data_bits (+5)", __FUNCTION__,
1011             stop_bits, parity_enable, parity_type, data_bits);
1012
1013         cypress_serial_control(port, baud_mask, data_bits, stop_bits, parity_enable,
1014                                parity_type, 0, CYPRESS_SET_CONFIG);
1015
1016         /* we perform a CYPRESS_GET_CONFIG so that the current settings are filled into the private structure
1017          * this should confirm that all is working if it returns what we just set */
1018         cypress_serial_control(port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
1019
1020         /* Here we can define custom tty settings for devices
1021          *
1022          * the main tty termios flag base comes from empeg.c
1023          */
1024
1025         spin_lock_irqsave(&priv->lock, flags);  
1026         if ( (priv->chiptype == CT_EARTHMATE) && (priv->baud_rate == 4800) ) {
1027
1028                 dbg("Using custom termios settings for a baud rate of 4800bps.");
1029                 /* define custom termios settings for NMEA protocol */
1030
1031                 tty->termios->c_iflag /* input modes - */
1032                         &= ~(IGNBRK             /* disable ignore break */
1033                         | BRKINT                /* disable break causes interrupt */
1034                         | PARMRK                /* disable mark parity errors */
1035                         | ISTRIP                /* disable clear high bit of input characters */
1036                         | INLCR                 /* disable translate NL to CR */
1037                         | IGNCR                 /* disable ignore CR */
1038                         | ICRNL                 /* disable translate CR to NL */
1039                         | IXON);                /* disable enable XON/XOFF flow control */
1040                 
1041                 tty->termios->c_oflag /* output modes */
1042                         &= ~OPOST;              /* disable postprocess output characters */
1043                 
1044                 tty->termios->c_lflag /* line discipline modes */
1045                         &= ~(ECHO               /* disable echo input characters */
1046                         | ECHONL                /* disable echo new line */
1047                         | ICANON                /* disable erase, kill, werase, and rprnt special characters */
1048                         | ISIG                  /* disable interrupt, quit, and suspend special characters */
1049                         | IEXTEN);              /* disable non-POSIX special characters */
1050
1051         } /* CT_CYPHIDCOM: Application should handle this for device */
1052
1053         linechange = (priv->line_control != oldlines);
1054         spin_unlock_irqrestore(&priv->lock, flags);
1055
1056         /* if necessary, set lines */
1057         if (linechange) {
1058                 priv->cmd_ctrl = 1;
1059                 cypress_write(port, NULL, 0);
1060         }
1061 } /* cypress_set_termios */
1062
1063  
1064 /* returns amount of data still left in soft buffer */
1065 static int cypress_chars_in_buffer(struct usb_serial_port *port)
1066 {
1067         struct cypress_private *priv = usb_get_serial_port_data(port);
1068         int chars = 0;
1069         unsigned long flags;
1070
1071         dbg("%s - port %d", __FUNCTION__, port->number);
1072         
1073         spin_lock_irqsave(&priv->lock, flags);
1074         chars = cypress_buf_data_avail(priv->buf);
1075         spin_unlock_irqrestore(&priv->lock, flags);
1076
1077         dbg("%s - returns %d", __FUNCTION__, chars);
1078         return chars;
1079 }
1080
1081
1082 static void cypress_throttle (struct usb_serial_port *port)
1083 {
1084         struct cypress_private *priv = usb_get_serial_port_data(port);
1085         unsigned long flags;
1086
1087         dbg("%s - port %d", __FUNCTION__, port->number);
1088
1089         spin_lock_irqsave(&priv->lock, flags);
1090         priv->rx_flags = THROTTLED;
1091         spin_unlock_irqrestore(&priv->lock, flags);        
1092 }
1093
1094
1095 static void cypress_unthrottle (struct usb_serial_port *port)
1096 {
1097         struct cypress_private *priv = usb_get_serial_port_data(port);
1098         int actually_throttled, result;
1099         unsigned long flags;
1100
1101         dbg("%s - port %d", __FUNCTION__, port->number);
1102
1103         spin_lock_irqsave(&priv->lock, flags);
1104         actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1105         priv->rx_flags = 0;
1106         spin_unlock_irqrestore(&priv->lock, flags);
1107
1108         if (actually_throttled) {
1109                 port->interrupt_in_urb->dev = port->serial->dev;
1110
1111                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1112                 if (result)
1113                         dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
1114         }
1115 }
1116
1117
1118 static void cypress_read_int_callback(struct urb *urb, struct pt_regs *regs)
1119 {
1120         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
1121         struct cypress_private *priv = usb_get_serial_port_data(port);
1122         struct tty_struct *tty;
1123         unsigned char *data = urb->transfer_buffer;
1124         unsigned long flags;
1125         char tty_flag = TTY_NORMAL;     
1126         int havedata = 0;
1127         int bytes = 0;
1128         int result;
1129         int i = 0;
1130
1131         dbg("%s - port %d", __FUNCTION__, port->number);
1132
1133         if (urb->status) {
1134                 dbg("%s - nonzero read status received: %d", __FUNCTION__, urb->status);
1135                 return;
1136         }
1137
1138         spin_lock_irqsave(&priv->lock, flags);
1139         if (priv->rx_flags & THROTTLED) {
1140                 dbg("%s - now throttling", __FUNCTION__);
1141                 priv->rx_flags |= ACTUALLY_THROTTLED;
1142                 spin_unlock_irqrestore(&priv->lock, flags);
1143                 return;
1144         }
1145         spin_unlock_irqrestore(&priv->lock, flags);
1146
1147         tty = port->tty;
1148         if (!tty) {
1149                 dbg("%s - bad tty pointer - exiting", __FUNCTION__);
1150                 return;
1151         }
1152
1153         spin_lock_irqsave(&priv->lock, flags);
1154         switch(urb->actual_length) {
1155                 case 32:
1156                         /* This is for the CY7C64013... */
1157                         priv->current_status = data[0] & 0xF8;
1158                         bytes = data[1]+2;
1159                         i=2;
1160                         if (bytes > 2)
1161                                 havedata = 1;
1162                         break;
1163                 case 8:
1164                         /* This is for the CY7C63743... */
1165                         priv->current_status = data[0] & 0xF8;
1166                         bytes = (data[0] & 0x07)+1;
1167                         i=1;
1168                         if (bytes > 1)
1169                                 havedata = 1;
1170                         break;
1171                 default:
1172                         dbg("%s - wrong packet size - received %d bytes", __FUNCTION__, urb->actual_length);
1173                         spin_unlock_irqrestore(&priv->lock, flags);
1174                         goto continue_read;
1175         }
1176         spin_unlock_irqrestore(&priv->lock, flags);
1177
1178         usb_serial_debug_data (debug, &port->dev, __FUNCTION__, urb->actual_length, data);
1179
1180         spin_lock_irqsave(&priv->lock, flags);
1181         /* check to see if status has changed */
1182         if (priv != NULL) {
1183                 if (priv->current_status != priv->prev_status) {
1184                         priv->diff_status |= priv->current_status ^ priv->prev_status;
1185                         wake_up_interruptible(&priv->delta_msr_wait);
1186                         priv->prev_status = priv->current_status;
1187                 }
1188         }
1189         spin_unlock_irqrestore(&priv->lock, flags);     
1190
1191         /* hangup, as defined in acm.c... this might be a bad place for it though */
1192         if (tty && !(tty->termios->c_cflag & CLOCAL) && !(priv->current_status & UART_CD)) {
1193                 dbg("%s - calling hangup", __FUNCTION__);
1194                 tty_hangup(tty);
1195                 goto continue_read;
1196         }
1197
1198         /* There is one error bit... I'm assuming it is a parity error indicator
1199          * as the generic firmware will set this bit to 1 if a parity error occurs.
1200          * I can not find reference to any other error events.
1201          *
1202          */
1203         spin_lock_irqsave(&priv->lock, flags);
1204         if (priv->current_status & CYP_ERROR) {
1205                 spin_unlock_irqrestore(&priv->lock, flags);
1206                 tty_flag = TTY_PARITY;
1207                 dbg("%s - Parity Error detected", __FUNCTION__);
1208         } else
1209                 spin_unlock_irqrestore(&priv->lock, flags);
1210
1211         /* process read if there is data other than line status */
1212         if (tty && (bytes > i)) {
1213                 for (; i < bytes ; ++i) {
1214                         dbg("pushing byte number %d - %d - %c",i,data[i],data[i]);
1215                         if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
1216                                 tty_flip_buffer_push(tty);
1217                         }
1218                         tty_insert_flip_char(tty, data[i], tty_flag);
1219                 }
1220                 tty_flip_buffer_push(port->tty);
1221         }
1222
1223         spin_lock_irqsave(&priv->lock, flags);
1224         priv->bytes_in += bytes;  /* control and status byte(s) are also counted */
1225         spin_unlock_irqrestore(&priv->lock, flags);
1226
1227 continue_read:
1228         
1229         /* Continue trying to always read... unless the port has closed.  */
1230
1231         if (port->open_count > 0) {
1232         usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1233                 usb_rcvintpipe(port->serial->dev, port->interrupt_in_endpointAddress),
1234                 port->interrupt_in_urb->transfer_buffer,
1235                 port->interrupt_in_urb->transfer_buffer_length,
1236                 cypress_read_int_callback, port,
1237                 interval);
1238         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1239         if (result)
1240                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
1241         }
1242         
1243         return;
1244 } /* cypress_read_int_callback */
1245
1246
1247 static void cypress_write_int_callback(struct urb *urb, struct pt_regs *regs)
1248 {
1249         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
1250         struct cypress_private *priv = usb_get_serial_port_data(port);
1251         int result;
1252
1253         dbg("%s - port %d", __FUNCTION__, port->number);
1254         
1255         switch (urb->status) {
1256                 case 0:
1257                         /* success */
1258                         break;
1259                 case -ECONNRESET:
1260                 case -ENOENT:
1261                 case -ESHUTDOWN:
1262                         /* this urb is terminated, clean up */
1263                         dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
1264                         priv->write_urb_in_use = 0;
1265                         return;
1266                 case -EPIPE: /* no break needed */
1267                         usb_clear_halt(port->serial->dev, 0x02);
1268                 default:
1269                         /* error in the urb, so we have to resubmit it */
1270                         dbg("%s - Overflow in write", __FUNCTION__);
1271                         dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
1272                         port->interrupt_out_urb->transfer_buffer_length = 1;
1273                         port->interrupt_out_urb->dev = port->serial->dev;
1274                         result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
1275                         if (result)
1276                                 dev_err(&urb->dev->dev, "%s - failed resubmitting write urb, error %d\n",
1277                                         __FUNCTION__, result);
1278                         else
1279                                 return;
1280         }
1281         
1282         priv->write_urb_in_use = 0;
1283         
1284         /* send any buffered data */
1285         cypress_send(port);
1286 }
1287
1288
1289 /*****************************************************************************
1290  * Write buffer functions - buffering code from pl2303 used
1291  *****************************************************************************/
1292
1293 /*
1294  * cypress_buf_alloc
1295  *
1296  * Allocate a circular buffer and all associated memory.
1297  */
1298
1299 static struct cypress_buf *cypress_buf_alloc(unsigned int size)
1300 {
1301
1302         struct cypress_buf *cb;
1303
1304
1305         if (size == 0)
1306                 return NULL;
1307
1308         cb = (struct cypress_buf *)kmalloc(sizeof(struct cypress_buf), GFP_KERNEL);
1309         if (cb == NULL)
1310                 return NULL;
1311
1312         cb->buf_buf = kmalloc(size, GFP_KERNEL);
1313         if (cb->buf_buf == NULL) {
1314                 kfree(cb);
1315                 return NULL;
1316         }
1317
1318         cb->buf_size = size;
1319         cb->buf_get = cb->buf_put = cb->buf_buf;
1320
1321         return cb;
1322
1323 }
1324
1325
1326 /*
1327  * cypress_buf_free
1328  *
1329  * Free the buffer and all associated memory.
1330  */
1331
1332 static void cypress_buf_free(struct cypress_buf *cb)
1333 {
1334         if (cb) {
1335                 kfree(cb->buf_buf);
1336                 kfree(cb);
1337         }
1338 }
1339
1340
1341 /*
1342  * cypress_buf_clear
1343  *
1344  * Clear out all data in the circular buffer.
1345  */
1346
1347 static void cypress_buf_clear(struct cypress_buf *cb)
1348 {
1349         if (cb != NULL)
1350                 cb->buf_get = cb->buf_put;
1351                 /* equivalent to a get of all data available */
1352 }
1353
1354
1355 /*
1356  * cypress_buf_data_avail
1357  *
1358  * Return the number of bytes of data available in the circular
1359  * buffer.
1360  */
1361
1362 static unsigned int cypress_buf_data_avail(struct cypress_buf *cb)
1363 {
1364         if (cb != NULL)
1365                 return ((cb->buf_size + cb->buf_put - cb->buf_get) % cb->buf_size);
1366         else
1367                 return 0;
1368 }
1369
1370
1371 /*
1372  * cypress_buf_space_avail
1373  *
1374  * Return the number of bytes of space available in the circular
1375  * buffer.
1376  */
1377
1378 static unsigned int cypress_buf_space_avail(struct cypress_buf *cb)
1379 {
1380         if (cb != NULL)
1381                 return ((cb->buf_size + cb->buf_get - cb->buf_put - 1) % cb->buf_size);
1382         else
1383                 return 0;
1384 }
1385
1386
1387 /*
1388  * cypress_buf_put
1389  *
1390  * Copy data data from a user buffer and put it into the circular buffer.
1391  * Restrict to the amount of space available.
1392  *
1393  * Return the number of bytes copied.
1394  */
1395
1396 static unsigned int cypress_buf_put(struct cypress_buf *cb, const char *buf,
1397         unsigned int count)
1398 {
1399
1400         unsigned int len;
1401
1402
1403         if (cb == NULL)
1404                 return 0;
1405
1406         len  = cypress_buf_space_avail(cb);
1407         if (count > len)
1408                 count = len;
1409
1410         if (count == 0)
1411                 return 0;
1412
1413         len = cb->buf_buf + cb->buf_size - cb->buf_put;
1414         if (count > len) {
1415                 memcpy(cb->buf_put, buf, len);
1416                 memcpy(cb->buf_buf, buf+len, count - len);
1417                 cb->buf_put = cb->buf_buf + count - len;
1418         } else {
1419                 memcpy(cb->buf_put, buf, count);
1420                 if (count < len)
1421                         cb->buf_put += count;
1422                 else /* count == len */
1423                         cb->buf_put = cb->buf_buf;
1424         }
1425
1426         return count;
1427
1428 }
1429
1430
1431 /*
1432  * cypress_buf_get
1433  *
1434  * Get data from the circular buffer and copy to the given buffer.
1435  * Restrict to the amount of data available.
1436  *
1437  * Return the number of bytes copied.
1438  */
1439
1440 static unsigned int cypress_buf_get(struct cypress_buf *cb, char *buf,
1441         unsigned int count)
1442 {
1443
1444         unsigned int len;
1445
1446
1447         if (cb == NULL)
1448                 return 0;
1449
1450         len = cypress_buf_data_avail(cb);
1451         if (count > len)
1452                 count = len;
1453
1454         if (count == 0)
1455                 return 0;
1456
1457         len = cb->buf_buf + cb->buf_size - cb->buf_get;
1458         if (count > len) {
1459                 memcpy(buf, cb->buf_get, len);
1460                 memcpy(buf+len, cb->buf_buf, count - len);
1461                 cb->buf_get = cb->buf_buf + count - len;
1462         } else {
1463                 memcpy(buf, cb->buf_get, count);
1464                 if (count < len)
1465                         cb->buf_get += count;
1466                 else /* count == len */
1467                         cb->buf_get = cb->buf_buf;
1468         }
1469
1470         return count;
1471
1472 }
1473
1474 /*****************************************************************************
1475  * Module functions
1476  *****************************************************************************/
1477
1478 static int __init cypress_init(void)
1479 {
1480         int retval;
1481         
1482         dbg("%s", __FUNCTION__);
1483         
1484         retval = usb_serial_register(&cypress_earthmate_device);
1485         if (retval)
1486                 goto failed_em_register;
1487         retval = usb_serial_register(&cypress_hidcom_device);
1488         if (retval)
1489                 goto failed_hidcom_register;
1490         retval = usb_register(&cypress_driver);
1491         if (retval)
1492                 goto failed_usb_register;
1493
1494         info(DRIVER_DESC " " DRIVER_VERSION);
1495         return 0;
1496 failed_usb_register:
1497         usb_deregister(&cypress_driver);
1498 failed_hidcom_register:
1499         usb_serial_deregister(&cypress_hidcom_device);
1500 failed_em_register:
1501         usb_serial_deregister(&cypress_earthmate_device);
1502
1503         return retval;
1504 }
1505
1506
1507 static void __exit cypress_exit (void)
1508 {
1509         dbg("%s", __FUNCTION__);
1510
1511         usb_deregister (&cypress_driver);
1512         usb_serial_deregister (&cypress_earthmate_device);
1513         usb_serial_deregister (&cypress_hidcom_device);
1514 }
1515
1516
1517 module_init(cypress_init);
1518 module_exit(cypress_exit);
1519
1520 MODULE_AUTHOR( DRIVER_AUTHOR );
1521 MODULE_DESCRIPTION( DRIVER_DESC );
1522 MODULE_VERSION( DRIVER_VERSION );
1523 MODULE_LICENSE("GPL");
1524
1525 module_param(debug, bool, S_IRUGO | S_IWUSR);
1526 MODULE_PARM_DESC(debug, "Debug enabled or not");
1527 module_param(stats, bool, S_IRUGO | S_IWUSR);
1528 MODULE_PARM_DESC(stats, "Enable statistics or not");
1529 module_param(interval, int, S_IRUGO | S_IWUSR);
1530 MODULE_PARM_DESC(interval, "Overrides interrupt interval");