Merge master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6
[linux-2.6] / drivers / usb / serial / generic.c
1 /*
2  * USB Serial Converter Generic functions
3  *
4  * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
5  *
6  *      This program is free software; you can redistribute it and/or
7  *      modify it under the terms of the GNU General Public License version
8  *      2 as published by the Free Software Foundation.
9  *
10  */
11
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/slab.h>
15 #include <linux/tty.h>
16 #include <linux/tty_flip.h>
17 #include <linux/module.h>
18 #include <linux/moduleparam.h>
19 #include <linux/usb.h>
20 #include <linux/usb/serial.h>
21 #include <asm/uaccess.h>
22
23
24 static int debug;
25
26 #ifdef CONFIG_USB_SERIAL_GENERIC
27
28 static int generic_probe(struct usb_interface *interface,
29                          const struct usb_device_id *id);
30
31 static __u16 vendor  = 0x05f9;
32 static __u16 product = 0xffff;
33
34 module_param(vendor, ushort, 0);
35 MODULE_PARM_DESC(vendor, "User specified USB idVendor");
36
37 module_param(product, ushort, 0);
38 MODULE_PARM_DESC(product, "User specified USB idProduct");
39
40 static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */
41
42 /* we want to look at all devices, as the vendor/product id can change
43  * depending on the command line argument */
44 static struct usb_device_id generic_serial_ids[] = {
45         {.driver_info = 42},
46         {}
47 };
48
49 static struct usb_driver generic_driver = {
50         .name =         "usbserial_generic",
51         .probe =        generic_probe,
52         .disconnect =   usb_serial_disconnect,
53         .id_table =     generic_serial_ids,
54         .no_dynamic_id =        1,
55 };
56
57 /* All of the device info needed for the Generic Serial Converter */
58 struct usb_serial_driver usb_serial_generic_device = {
59         .driver = {
60                 .owner =        THIS_MODULE,
61                 .name =         "generic",
62         },
63         .id_table =             generic_device_ids,
64         .usb_driver =           &generic_driver,
65         .num_interrupt_in =     NUM_DONT_CARE,
66         .num_bulk_in =          NUM_DONT_CARE,
67         .num_bulk_out =         NUM_DONT_CARE,
68         .num_ports =            1,
69         .shutdown =             usb_serial_generic_shutdown,
70         .throttle =             usb_serial_generic_throttle,
71         .unthrottle =           usb_serial_generic_unthrottle,
72         .resume =               usb_serial_generic_resume,
73 };
74
75 static int generic_probe(struct usb_interface *interface,
76                                const struct usb_device_id *id)
77 {
78         const struct usb_device_id *id_pattern;
79
80         id_pattern = usb_match_id(interface, generic_device_ids);
81         if (id_pattern != NULL)
82                 return usb_serial_probe(interface, id);
83         return -ENODEV;
84 }
85 #endif
86
87 int usb_serial_generic_register (int _debug)
88 {
89         int retval = 0;
90
91         debug = _debug;
92 #ifdef CONFIG_USB_SERIAL_GENERIC
93         generic_device_ids[0].idVendor = vendor;
94         generic_device_ids[0].idProduct = product;
95         generic_device_ids[0].match_flags = USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT;
96
97         /* register our generic driver with ourselves */
98         retval = usb_serial_register (&usb_serial_generic_device);
99         if (retval)
100                 goto exit;
101         retval = usb_register(&generic_driver);
102         if (retval)
103                 usb_serial_deregister(&usb_serial_generic_device);
104 exit:
105 #endif
106         return retval;
107 }
108
109 void usb_serial_generic_deregister (void)
110 {
111 #ifdef CONFIG_USB_SERIAL_GENERIC
112         /* remove our generic driver */
113         usb_deregister(&generic_driver);
114         usb_serial_deregister (&usb_serial_generic_device);
115 #endif
116 }
117
118 int usb_serial_generic_open (struct usb_serial_port *port, struct file *filp)
119 {
120         struct usb_serial *serial = port->serial;
121         int result = 0;
122         unsigned long flags;
123
124         dbg("%s - port %d", __FUNCTION__, port->number);
125
126         /* force low_latency on so that our tty_push actually forces the data through, 
127            otherwise it is scheduled, and with high data rates (like with OHCI) data
128            can get lost. */
129         if (port->tty)
130                 port->tty->low_latency = 1;
131
132         /* clear the throttle flags */
133         spin_lock_irqsave(&port->lock, flags);
134         port->throttled = 0;
135         port->throttle_req = 0;
136         spin_unlock_irqrestore(&port->lock, flags);
137
138         /* if we have a bulk endpoint, start reading from it */
139         if (serial->num_bulk_in) {
140                 /* Start reading from the device */
141                 usb_fill_bulk_urb (port->read_urb, serial->dev,
142                                    usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
143                                    port->read_urb->transfer_buffer,
144                                    port->read_urb->transfer_buffer_length,
145                                    ((serial->type->read_bulk_callback) ?
146                                      serial->type->read_bulk_callback :
147                                      usb_serial_generic_read_bulk_callback),
148                                    port);
149                 result = usb_submit_urb(port->read_urb, GFP_KERNEL);
150                 if (result)
151                         dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
152         }
153
154         return result;
155 }
156 EXPORT_SYMBOL_GPL(usb_serial_generic_open);
157
158 static void generic_cleanup (struct usb_serial_port *port)
159 {
160         struct usb_serial *serial = port->serial;
161
162         dbg("%s - port %d", __FUNCTION__, port->number);
163
164         if (serial->dev) {
165                 /* shutdown any bulk reads that might be going on */
166                 if (serial->num_bulk_out)
167                         usb_kill_urb(port->write_urb);
168                 if (serial->num_bulk_in)
169                         usb_kill_urb(port->read_urb);
170         }
171 }
172
173 int usb_serial_generic_resume(struct usb_serial *serial)
174 {
175         struct usb_serial_port *port;
176         int i, c = 0, r;
177
178         for (i = 0; i < serial->num_ports; i++) {
179                 port = serial->port[i];
180                 if (port->open_count && port->read_urb) {
181                         r = usb_submit_urb(port->read_urb, GFP_NOIO);
182                         if (r < 0)
183                                 c++;
184                 }
185         }
186
187         return c ? -EIO : 0;
188 }
189
190 void usb_serial_generic_close (struct usb_serial_port *port, struct file * filp)
191 {
192         dbg("%s - port %d", __FUNCTION__, port->number);
193         generic_cleanup (port);
194 }
195
196 int usb_serial_generic_write(struct usb_serial_port *port, const unsigned char *buf, int count)
197 {
198         struct usb_serial *serial = port->serial;
199         int result;
200         unsigned char *data;
201
202         dbg("%s - port %d", __FUNCTION__, port->number);
203
204         if (count == 0) {
205                 dbg("%s - write request of 0 bytes", __FUNCTION__);
206                 return (0);
207         }
208
209         /* only do something if we have a bulk out endpoint */
210         if (serial->num_bulk_out) {
211                 spin_lock_bh(&port->lock);
212                 if (port->write_urb_busy) {
213                         spin_unlock_bh(&port->lock);
214                         dbg("%s - already writing", __FUNCTION__);
215                         return 0;
216                 }
217                 port->write_urb_busy = 1;
218                 spin_unlock_bh(&port->lock);
219
220                 count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
221
222                 memcpy (port->write_urb->transfer_buffer, buf, count);
223                 data = port->write_urb->transfer_buffer;
224                 usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, data);
225
226                 /* set up our urb */
227                 usb_fill_bulk_urb (port->write_urb, serial->dev,
228                                    usb_sndbulkpipe (serial->dev,
229                                                     port->bulk_out_endpointAddress),
230                                    port->write_urb->transfer_buffer, count,
231                                    ((serial->type->write_bulk_callback) ? 
232                                      serial->type->write_bulk_callback :
233                                      usb_serial_generic_write_bulk_callback), port);
234
235                 /* send the data out the bulk port */
236                 port->write_urb_busy = 1;
237                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
238                 if (result) {
239                         dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
240                         /* don't have to grab the lock here, as we will retry if != 0 */
241                         port->write_urb_busy = 0;
242                 } else
243                         result = count;
244
245                 return result;
246         }
247
248         /* no bulk out, so return 0 bytes written */
249         return 0;
250 }
251
252 int usb_serial_generic_write_room (struct usb_serial_port *port)
253 {
254         struct usb_serial *serial = port->serial;
255         int room = 0;
256
257         dbg("%s - port %d", __FUNCTION__, port->number);
258
259         if (serial->num_bulk_out) {
260                 if (!(port->write_urb_busy))
261                         room = port->bulk_out_size;
262         }
263
264         dbg("%s - returns %d", __FUNCTION__, room);
265         return (room);
266 }
267
268 int usb_serial_generic_chars_in_buffer (struct usb_serial_port *port)
269 {
270         struct usb_serial *serial = port->serial;
271         int chars = 0;
272
273         dbg("%s - port %d", __FUNCTION__, port->number);
274
275         if (serial->num_bulk_out) {
276                 if (port->write_urb_busy)
277                         chars = port->write_urb->transfer_buffer_length;
278         }
279
280         dbg("%s - returns %d", __FUNCTION__, chars);
281         return (chars);
282 }
283
284
285 static void resubmit_read_urb(struct usb_serial_port *port, gfp_t mem_flags)
286 {
287         struct urb *urb = port->read_urb;
288         struct usb_serial *serial = port->serial;
289         int result;
290
291         /* Continue reading from device */
292         usb_fill_bulk_urb (urb, serial->dev,
293                            usb_rcvbulkpipe (serial->dev,
294                                             port->bulk_in_endpointAddress),
295                            urb->transfer_buffer,
296                            urb->transfer_buffer_length,
297                            ((serial->type->read_bulk_callback) ? 
298                              serial->type->read_bulk_callback : 
299                              usb_serial_generic_read_bulk_callback), port);
300         result = usb_submit_urb(urb, mem_flags);
301         if (result)
302                 dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
303 }
304
305 /* Push data to tty layer and resubmit the bulk read URB */
306 static void flush_and_resubmit_read_urb (struct usb_serial_port *port)
307 {
308         struct urb *urb = port->read_urb;
309         struct tty_struct *tty = port->tty;
310         int room;
311
312         /* Push data to tty */
313         if (tty && urb->actual_length) {
314                 room = tty_buffer_request_room(tty, urb->actual_length);
315                 if (room) {
316                         tty_insert_flip_string(tty, urb->transfer_buffer, room);
317                         tty_flip_buffer_push(tty); /* is this allowed from an URB callback ? */
318                 }
319         }
320
321         resubmit_read_urb(port, GFP_ATOMIC);
322 }
323
324 void usb_serial_generic_read_bulk_callback (struct urb *urb)
325 {
326         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
327         unsigned char *data = urb->transfer_buffer;
328         int status = urb->status;
329
330         dbg("%s - port %d", __FUNCTION__, port->number);
331
332         if (unlikely(status != 0)) {
333                 dbg("%s - nonzero read bulk status received: %d",
334                     __FUNCTION__, status);
335                 return;
336         }
337
338         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
339
340         /* Throttle the device if requested by tty */
341         spin_lock(&port->lock);
342         if (!(port->throttled = port->throttle_req))
343                 /* Handle data and continue reading from device */
344                 flush_and_resubmit_read_urb(port);
345         spin_unlock(&port->lock);
346 }
347 EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback);
348
349 void usb_serial_generic_write_bulk_callback (struct urb *urb)
350 {
351         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
352         int status = urb->status;
353
354         dbg("%s - port %d", __FUNCTION__, port->number);
355
356         port->write_urb_busy = 0;
357         if (status) {
358                 dbg("%s - nonzero write bulk status received: %d",
359                     __FUNCTION__, status);
360                 return;
361         }
362
363         usb_serial_port_softint(port);
364 }
365 EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
366
367 void usb_serial_generic_throttle (struct usb_serial_port *port)
368 {
369         unsigned long flags;
370
371         dbg("%s - port %d", __FUNCTION__, port->number);
372
373         /* Set the throttle request flag. It will be picked up
374          * by usb_serial_generic_read_bulk_callback(). */
375         spin_lock_irqsave(&port->lock, flags);
376         port->throttle_req = 1;
377         spin_unlock_irqrestore(&port->lock, flags);
378 }
379
380 void usb_serial_generic_unthrottle (struct usb_serial_port *port)
381 {
382         int was_throttled;
383         unsigned long flags;
384
385         dbg("%s - port %d", __FUNCTION__, port->number);
386
387         /* Clear the throttle flags */
388         spin_lock_irqsave(&port->lock, flags);
389         was_throttled = port->throttled;
390         port->throttled = port->throttle_req = 0;
391         spin_unlock_irqrestore(&port->lock, flags);
392
393         if (was_throttled) {
394                 /* Resume reading from device */
395                 resubmit_read_urb(port, GFP_KERNEL);
396         }
397 }
398
399 void usb_serial_generic_shutdown (struct usb_serial *serial)
400 {
401         int i;
402
403         dbg("%s", __FUNCTION__);
404
405         /* stop reads and writes on all ports */
406         for (i=0; i < serial->num_ports; ++i) {
407                 generic_cleanup(serial->port[i]);
408         }
409 }
410