[PATCH] TTY layer buffering revamp
[safe/jmp/linux-2.6] / drivers / usb / serial / cyberjack.c
1 /*
2  *  REINER SCT cyberJack pinpad/e-com USB Chipcard Reader Driver
3  *
4  *  Copyright (C) 2001  REINER SCT
5  *  Author: Matthias Bruestle
6  *
7  *  Contact: support@reiner-sct.com (see MAINTAINERS)
8  *
9  *  This program is largely derived from work by the linux-usb group
10  *  and associated source files.  Please see the usb/serial files for
11  *  individual credits and copyrights.
12  *
13  *  This program is free software; you can redistribute it and/or modify
14  *  it under the terms of the GNU General Public License as published by
15  *  the Free Software Foundation; either version 2 of the License, or
16  *  (at your option) any later version.
17  *
18  *  Thanks to Greg Kroah-Hartman (greg@kroah.com) for his help and
19  *  patience.
20  *
21  *  In case of problems, please write to the contact e-mail address
22  *  mentioned above.
23  *
24  *  Please note that later models of the cyberjack reader family are
25  *  supported by a libusb-based userspace device driver.
26  *
27  *  Homepage: http://www.reiner-sct.de/support/treiber_cyberjack.php#linux
28  */
29
30
31 #include <linux/config.h>
32 #include <linux/kernel.h>
33 #include <linux/errno.h>
34 #include <linux/init.h>
35 #include <linux/slab.h>
36 #include <linux/tty.h>
37 #include <linux/tty_driver.h>
38 #include <linux/tty_flip.h>
39 #include <linux/module.h>
40 #include <linux/spinlock.h>
41 #include <asm/uaccess.h>
42 #include <linux/usb.h>
43 #include "usb-serial.h"
44
45 #define CYBERJACK_LOCAL_BUF_SIZE 32
46
47 static int debug;
48
49 /*
50  * Version Information
51  */
52 #define DRIVER_VERSION "v1.01"
53 #define DRIVER_AUTHOR "Matthias Bruestle"
54 #define DRIVER_DESC "REINER SCT cyberJack pinpad/e-com USB Chipcard Reader Driver"
55
56
57 #define CYBERJACK_VENDOR_ID     0x0C4B
58 #define CYBERJACK_PRODUCT_ID    0x0100
59
60 /* Function prototypes */
61 static int cyberjack_startup (struct usb_serial *serial);
62 static void cyberjack_shutdown (struct usb_serial *serial);
63 static int  cyberjack_open (struct usb_serial_port *port, struct file *filp);
64 static void cyberjack_close (struct usb_serial_port *port, struct file *filp);
65 static int cyberjack_write (struct usb_serial_port *port, const unsigned char *buf, int count);
66 static int cyberjack_write_room( struct usb_serial_port *port );
67 static void cyberjack_read_int_callback (struct urb *urb, struct pt_regs *regs);
68 static void cyberjack_read_bulk_callback (struct urb *urb, struct pt_regs *regs);
69 static void cyberjack_write_bulk_callback (struct urb *urb, struct pt_regs *regs);
70
71 static struct usb_device_id id_table [] = {
72         { USB_DEVICE(CYBERJACK_VENDOR_ID, CYBERJACK_PRODUCT_ID) },
73         { }                     /* Terminating entry */
74 };
75
76 MODULE_DEVICE_TABLE (usb, id_table);
77
78 static struct usb_driver cyberjack_driver = {
79         .name =         "cyberjack",
80         .probe =        usb_serial_probe,
81         .disconnect =   usb_serial_disconnect,
82         .id_table =     id_table,
83         .no_dynamic_id =        1,
84 };
85
86 static struct usb_serial_driver cyberjack_device = {
87         .driver = {
88                 .owner =        THIS_MODULE,
89                 .name =         "cyberjack",
90         },
91         .description =          "Reiner SCT Cyberjack USB card reader",
92         .id_table =             id_table,
93         .num_interrupt_in =     1,
94         .num_bulk_in =          1,
95         .num_bulk_out =         1,
96         .num_ports =            1,
97         .attach =               cyberjack_startup,
98         .shutdown =             cyberjack_shutdown,
99         .open =                 cyberjack_open,
100         .close =                cyberjack_close,
101         .write =                cyberjack_write,
102         .write_room =   cyberjack_write_room,
103         .read_int_callback =    cyberjack_read_int_callback,
104         .read_bulk_callback =   cyberjack_read_bulk_callback,
105         .write_bulk_callback =  cyberjack_write_bulk_callback,
106 };
107
108 struct cyberjack_private {
109         spinlock_t      lock;           /* Lock for SMP */
110         short           rdtodo;         /* Bytes still to read */
111         unsigned char   wrbuf[5*64];    /* Buffer for collecting data to write */
112         short           wrfilled;       /* Overall data size we already got */
113         short           wrsent;         /* Data already sent */
114 };
115
116 /* do some startup allocations not currently performed by usb_serial_probe() */
117 static int cyberjack_startup (struct usb_serial *serial)
118 {
119         struct cyberjack_private *priv;
120         int i;
121
122         dbg("%s", __FUNCTION__);
123
124         /* allocate the private data structure */
125         priv = kmalloc(sizeof(struct cyberjack_private), GFP_KERNEL);
126         if (!priv)
127                 return -ENOMEM;
128
129         /* set initial values */
130         spin_lock_init(&priv->lock);
131         priv->rdtodo = 0;
132         priv->wrfilled = 0;
133         priv->wrsent = 0;
134         usb_set_serial_port_data(serial->port[0], priv);
135
136         init_waitqueue_head(&serial->port[0]->write_wait);
137
138         for (i = 0; i < serial->num_ports; ++i) {
139                 int result;
140                 serial->port[i]->interrupt_in_urb->dev = serial->dev;
141                 result = usb_submit_urb(serial->port[i]->interrupt_in_urb, 
142                                         GFP_KERNEL);
143                 if (result)
144                         err(" usb_submit_urb(read int) failed");
145                 dbg("%s - usb_submit_urb(int urb)", __FUNCTION__);
146         }
147
148         return( 0 );
149 }
150
151 static void cyberjack_shutdown (struct usb_serial *serial)
152 {
153         int i;
154         
155         dbg("%s", __FUNCTION__);
156
157         for (i=0; i < serial->num_ports; ++i) {
158                 usb_kill_urb(serial->port[i]->interrupt_in_urb);
159                 /* My special items, the standard routines free my urbs */
160                 kfree(usb_get_serial_port_data(serial->port[i]));
161                 usb_set_serial_port_data(serial->port[i], NULL);
162         }
163 }
164         
165 static int  cyberjack_open (struct usb_serial_port *port, struct file *filp)
166 {
167         struct cyberjack_private *priv;
168         unsigned long flags;
169         int result = 0;
170
171         dbg("%s - port %d", __FUNCTION__, port->number);
172
173         dbg("%s - usb_clear_halt", __FUNCTION__ );
174         usb_clear_halt(port->serial->dev, port->write_urb->pipe);
175
176         /* force low_latency on so that our tty_push actually forces
177          * the data through, otherwise it is scheduled, and with high
178          * data rates (like with OHCI) data can get lost.
179          */
180         port->tty->low_latency = 1;
181
182         priv = usb_get_serial_port_data(port);
183         spin_lock_irqsave(&priv->lock, flags);
184         priv->rdtodo = 0;
185         priv->wrfilled = 0;
186         priv->wrsent = 0;
187         spin_unlock_irqrestore(&priv->lock, flags);
188
189         return result;
190 }
191
192 static void cyberjack_close (struct usb_serial_port *port, struct file *filp)
193 {
194         dbg("%s - port %d", __FUNCTION__, port->number);
195
196         if (port->serial->dev) {
197                 /* shutdown any bulk reads that might be going on */
198                 usb_kill_urb(port->write_urb);
199                 usb_kill_urb(port->read_urb);
200         }
201 }
202
203 static int cyberjack_write (struct usb_serial_port *port, const unsigned char *buf, int count)
204 {
205         struct usb_serial *serial = port->serial;
206         struct cyberjack_private *priv = usb_get_serial_port_data(port);
207         unsigned long flags;
208         int result;
209         int wrexpected;
210
211         dbg("%s - port %d", __FUNCTION__, port->number);
212
213         if (count == 0) {
214                 dbg("%s - write request of 0 bytes", __FUNCTION__);
215                 return (0);
216         }
217
218         spin_lock(&port->lock);
219         if (port->write_urb_busy) {
220                 spin_unlock(&port->lock);
221                 dbg("%s - already writing", __FUNCTION__);
222                 return 0;
223         }
224         port->write_urb_busy = 1;
225         spin_unlock(&port->lock);
226
227         spin_lock_irqsave(&priv->lock, flags);
228
229         if( (count+priv->wrfilled)>sizeof(priv->wrbuf) ) {
230                 /* To much data for buffer. Reset buffer. */
231                 priv->wrfilled=0;
232                 spin_unlock_irqrestore(&priv->lock, flags);
233                 port->write_urb_busy = 0;
234                 return (0);
235         }
236
237         /* Copy data */
238         memcpy (priv->wrbuf+priv->wrfilled, buf, count);
239
240         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count,
241                 priv->wrbuf+priv->wrfilled);
242         priv->wrfilled += count;
243
244         if( priv->wrfilled >= 3 ) {
245                 wrexpected = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
246                 dbg("%s - expected data: %d", __FUNCTION__, wrexpected);
247         } else {
248                 wrexpected = sizeof(priv->wrbuf);
249         }
250
251         if( priv->wrfilled >= wrexpected ) {
252                 /* We have enough data to begin transmission */
253                 int length;
254
255                 dbg("%s - transmitting data (frame 1)", __FUNCTION__);
256                 length = (wrexpected > port->bulk_out_size) ? port->bulk_out_size : wrexpected;
257
258                 memcpy (port->write_urb->transfer_buffer, priv->wrbuf, length );
259                 priv->wrsent=length;
260
261                 /* set up our urb */
262                 usb_fill_bulk_urb(port->write_urb, serial->dev, 
263                               usb_sndbulkpipe(serial->dev, port->bulk_out_endpointAddress),
264                               port->write_urb->transfer_buffer, length,
265                               ((serial->type->write_bulk_callback) ? 
266                                serial->type->write_bulk_callback : 
267                                cyberjack_write_bulk_callback), 
268                               port);
269
270                 /* send the data out the bulk port */
271                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
272                 if (result) {
273                         err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
274                         /* Throw away data. No better idea what to do with it. */
275                         priv->wrfilled=0;
276                         priv->wrsent=0;
277                         spin_unlock_irqrestore(&priv->lock, flags);
278                         port->write_urb_busy = 0;
279                         return 0;
280                 }
281
282                 dbg("%s - priv->wrsent=%d", __FUNCTION__,priv->wrsent);
283                 dbg("%s - priv->wrfilled=%d", __FUNCTION__,priv->wrfilled);
284
285                 if( priv->wrsent>=priv->wrfilled ) {
286                         dbg("%s - buffer cleaned", __FUNCTION__);
287                         memset( priv->wrbuf, 0, sizeof(priv->wrbuf) );
288                         priv->wrfilled=0;
289                         priv->wrsent=0;
290                 }
291         }
292
293         spin_unlock_irqrestore(&priv->lock, flags);
294
295         return (count);
296
297
298 static int cyberjack_write_room( struct usb_serial_port *port )
299 {
300         return CYBERJACK_LOCAL_BUF_SIZE;
301 }
302
303 static void cyberjack_read_int_callback( struct urb *urb, struct pt_regs *regs )
304 {
305         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
306         struct cyberjack_private *priv = usb_get_serial_port_data(port);
307         unsigned char *data = urb->transfer_buffer;
308         int result;
309
310         dbg("%s - port %d", __FUNCTION__, port->number);
311
312         /* the urb might have been killed. */
313         if (urb->status)
314                 return;
315
316         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
317
318         /* React only to interrupts signaling a bulk_in transfer */
319         if( (urb->actual_length==4) && (data[0]==0x01) ) {
320                 short old_rdtodo;
321                 int result;
322
323                 /* This is a announcement of coming bulk_ins. */
324                 unsigned short size = ((unsigned short)data[3]<<8)+data[2]+3;
325
326                 spin_lock(&priv->lock);
327
328                 old_rdtodo = priv->rdtodo;
329
330                 if( (old_rdtodo+size)<(old_rdtodo) ) {
331                         dbg( "To many bulk_in urbs to do." );
332                         spin_unlock(&priv->lock);
333                         goto resubmit;
334                 }
335
336                 /* "+=" is probably more fault tollerant than "=" */
337                 priv->rdtodo += size;
338
339                 dbg("%s - rdtodo: %d", __FUNCTION__, priv->rdtodo);
340
341                 spin_unlock(&priv->lock);
342
343                 if( !old_rdtodo ) {
344                         port->read_urb->dev = port->serial->dev;
345                         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
346                         if( result )
347                                 err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
348                         dbg("%s - usb_submit_urb(read urb)", __FUNCTION__);
349                 }
350         }
351
352 resubmit:
353         port->interrupt_in_urb->dev = port->serial->dev;
354         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
355         if (result)
356                 err(" usb_submit_urb(read int) failed");
357         dbg("%s - usb_submit_urb(int urb)", __FUNCTION__);
358 }
359
360 static void cyberjack_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
361 {
362         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
363         struct cyberjack_private *priv = usb_get_serial_port_data(port);
364         struct tty_struct *tty;
365         unsigned char *data = urb->transfer_buffer;
366         short todo;
367         int result;
368
369         dbg("%s - port %d", __FUNCTION__, port->number);
370         
371         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
372         if (urb->status) {
373                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
374                 return;
375         }
376
377         tty = port->tty;
378         if (!tty) {
379                 dbg("%s - ignoring since device not open\n", __FUNCTION__);
380                 return;
381         }
382         if (urb->actual_length) {
383                 tty_buffer_request_room(tty, urb->actual_length);
384                 tty_insert_flip_string(tty, data, urb->actual_length);
385                 tty_flip_buffer_push(tty);
386         }
387
388         spin_lock(&priv->lock);
389
390         /* Reduce urbs to do by one. */
391         priv->rdtodo-=urb->actual_length;
392         /* Just to be sure */
393         if ( priv->rdtodo<0 ) priv->rdtodo = 0;
394         todo = priv->rdtodo;
395
396         spin_unlock(&priv->lock);
397
398         dbg("%s - rdtodo: %d", __FUNCTION__, todo);
399
400         /* Continue to read if we have still urbs to do. */
401         if( todo /* || (urb->actual_length==port->bulk_in_endpointAddress)*/ ) {
402                 port->read_urb->dev = port->serial->dev;
403                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
404                 if (result)
405                         err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
406                 dbg("%s - usb_submit_urb(read urb)", __FUNCTION__);
407         }
408 }
409
410 static void cyberjack_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
411 {
412         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
413         struct cyberjack_private *priv = usb_get_serial_port_data(port);
414
415         dbg("%s - port %d", __FUNCTION__, port->number);
416
417         port->write_urb_busy = 0;
418         if (urb->status) {
419                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
420                 return;
421         }
422
423         spin_lock(&priv->lock);
424
425         /* only do something if we have more data to send */
426         if( priv->wrfilled ) {
427                 int length, blksize, result;
428
429                 dbg("%s - transmitting data (frame n)", __FUNCTION__);
430
431                 length = ((priv->wrfilled - priv->wrsent) > port->bulk_out_size) ?
432                         port->bulk_out_size : (priv->wrfilled - priv->wrsent);
433
434                 memcpy (port->write_urb->transfer_buffer, priv->wrbuf + priv->wrsent,
435                         length );
436                 priv->wrsent+=length;
437
438                 /* set up our urb */
439                 usb_fill_bulk_urb(port->write_urb, port->serial->dev, 
440                               usb_sndbulkpipe(port->serial->dev, port->bulk_out_endpointAddress),
441                               port->write_urb->transfer_buffer, length,
442                               ((port->serial->type->write_bulk_callback) ? 
443                                port->serial->type->write_bulk_callback : 
444                                cyberjack_write_bulk_callback), 
445                               port);
446
447                 /* send the data out the bulk port */
448                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
449                 if (result) {
450                         err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
451                         /* Throw away data. No better idea what to do with it. */
452                         priv->wrfilled=0;
453                         priv->wrsent=0;
454                         goto exit;
455                 }
456
457                 dbg("%s - priv->wrsent=%d", __FUNCTION__,priv->wrsent);
458                 dbg("%s - priv->wrfilled=%d", __FUNCTION__,priv->wrfilled);
459
460                 blksize = ((int)priv->wrbuf[2]<<8)+priv->wrbuf[1]+3;
461
462                 if( (priv->wrsent>=priv->wrfilled) || (priv->wrsent>=blksize) ) {
463                         dbg("%s - buffer cleaned", __FUNCTION__);
464                         memset( priv->wrbuf, 0, sizeof(priv->wrbuf) );
465                         priv->wrfilled=0;
466                         priv->wrsent=0;
467                 }
468         }
469
470 exit:
471         spin_unlock(&priv->lock);
472         schedule_work(&port->work);
473 }
474
475 static int __init cyberjack_init (void)
476 {
477         int retval;
478         retval  = usb_serial_register(&cyberjack_device);
479         if (retval)
480                 goto failed_usb_serial_register;
481         retval = usb_register(&cyberjack_driver);
482         if (retval) 
483                 goto failed_usb_register;
484
485         info(DRIVER_VERSION " " DRIVER_AUTHOR);
486         info(DRIVER_DESC);
487
488         return 0;
489 failed_usb_register:
490         usb_serial_deregister(&cyberjack_device);
491 failed_usb_serial_register:
492         return retval;
493 }
494
495 static void __exit cyberjack_exit (void)
496 {
497         usb_deregister (&cyberjack_driver);
498         usb_serial_deregister (&cyberjack_device);
499 }
500
501 module_init(cyberjack_init);
502 module_exit(cyberjack_exit);
503
504 MODULE_AUTHOR( DRIVER_AUTHOR );
505 MODULE_DESCRIPTION( DRIVER_DESC );
506 MODULE_VERSION( DRIVER_VERSION );
507 MODULE_LICENSE("GPL");
508
509 module_param(debug, bool, S_IRUGO | S_IWUSR);
510 MODULE_PARM_DESC(debug, "Debug enabled or not");