ir-usb.c revision 90ab5ee94171b3e28de6bb42ee30b527014e0be7 
1/*
2 * USB IR Dongle driver
3 *
4 *	Copyright (C) 2001-2002	Greg Kroah-Hartman (greg@kroah.com)
5 *	Copyright (C) 2002	Gary Brubaker (xavyer@ix.netcom.com)
6 *	Copyright (C) 2010	Johan Hovold (jhovold@gmail.com)
7 *
8 *	This program is free software; you can redistribute it and/or modify
9 *	it under the terms of the GNU General Public License as published by
10 *	the Free Software Foundation; either version 2 of the License, or
11 *	(at your option) any later version.
12 *
13 * This driver allows a USB IrDA device to be used as a "dumb" serial device.
14 * This can be useful if you do not have access to a full IrDA stack on the
15 * other side of the connection.  If you do have an IrDA stack on both devices,
16 * please use the usb-irda driver, as it contains the proper error checking and
17 * other goodness of a full IrDA stack.
18 *
19 * Portions of this driver were taken from drivers/net/irda/irda-usb.c, which
20 * was written by Roman Weissgaerber <weissg@vienna.at>, Dag Brattli
21 * <dag@brattli.net>, and Jean Tourrilhes <jt@hpl.hp.com>
22 *
23 * See Documentation/usb/usb-serial.txt for more information on using this
24 * driver
25 */
26
27#include <linux/kernel.h>
28#include <linux/errno.h>
29#include <linux/init.h>
30#include <linux/slab.h>
31#include <linux/tty.h>
32#include <linux/tty_driver.h>
33#include <linux/tty_flip.h>
34#include <linux/module.h>
35#include <linux/spinlock.h>
36#include <linux/uaccess.h>
37#include <linux/usb.h>
38#include <linux/usb/serial.h>
39#include <linux/usb/irda.h>
40
41/*
42 * Version Information
43 */
44#define DRIVER_VERSION "v0.5"
45#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Johan Hovold <jhovold@gmail.com>"
46#define DRIVER_DESC "USB IR Dongle driver"
47
48static bool debug;
49
50/* if overridden by the user, then use their value for the size of the read and
51 * write urbs */
52static int buffer_size;
53
54/* if overridden by the user, then use the specified number of XBOFs */
55static int xbof = -1;
56
57static int  ir_startup (struct usb_serial *serial);
58static int  ir_open(struct tty_struct *tty, struct usb_serial_port *port);
59static int ir_prepare_write_buffer(struct usb_serial_port *port,
60						void *dest, size_t size);
61static void ir_process_read_urb(struct urb *urb);
62static void ir_set_termios(struct tty_struct *tty,
63		struct usb_serial_port *port, struct ktermios *old_termios);
64
65/* Not that this lot means you can only have one per system */
66static u8 ir_baud;
67static u8 ir_xbof;
68static u8 ir_add_bof;
69
70static const struct usb_device_id ir_id_table[] = {
71	{ USB_DEVICE(0x050f, 0x0180) },		/* KC Technology, KC-180 */
72	{ USB_DEVICE(0x08e9, 0x0100) },		/* XTNDAccess */
73	{ USB_DEVICE(0x09c4, 0x0011) },		/* ACTiSys ACT-IR2000U */
74	{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, USB_SUBCLASS_IRDA, 0) },
75	{ }					/* Terminating entry */
76};
77
78MODULE_DEVICE_TABLE(usb, ir_id_table);
79
80static struct usb_driver ir_driver = {
81	.name		= "ir-usb",
82	.probe		= usb_serial_probe,
83	.disconnect	= usb_serial_disconnect,
84	.id_table	= ir_id_table,
85	.no_dynamic_id	= 1,
86};
87
88static struct usb_serial_driver ir_device = {
89	.driver	= {
90		.owner	= THIS_MODULE,
91		.name	= "ir-usb",
92	},
93	.description		= "IR Dongle",
94	.usb_driver		= &ir_driver,
95	.id_table		= ir_id_table,
96	.num_ports		= 1,
97	.set_termios		= ir_set_termios,
98	.attach			= ir_startup,
99	.open			= ir_open,
100	.prepare_write_buffer	= ir_prepare_write_buffer,
101	.process_read_urb	= ir_process_read_urb,
102};
103
104static inline void irda_usb_dump_class_desc(struct usb_irda_cs_descriptor *desc)
105{
106	dbg("bLength=%x", desc->bLength);
107	dbg("bDescriptorType=%x", desc->bDescriptorType);
108	dbg("bcdSpecRevision=%x", __le16_to_cpu(desc->bcdSpecRevision));
109	dbg("bmDataSize=%x", desc->bmDataSize);
110	dbg("bmWindowSize=%x", desc->bmWindowSize);
111	dbg("bmMinTurnaroundTime=%d", desc->bmMinTurnaroundTime);
112	dbg("wBaudRate=%x", __le16_to_cpu(desc->wBaudRate));
113	dbg("bmAdditionalBOFs=%x", desc->bmAdditionalBOFs);
114	dbg("bIrdaRateSniff=%x", desc->bIrdaRateSniff);
115	dbg("bMaxUnicastList=%x", desc->bMaxUnicastList);
116}
117
118/*------------------------------------------------------------------*/
119/*
120 * Function irda_usb_find_class_desc(dev, ifnum)
121 *
122 *    Returns instance of IrDA class descriptor, or NULL if not found
123 *
124 * The class descriptor is some extra info that IrDA USB devices will
125 * offer to us, describing their IrDA characteristics. We will use that in
126 * irda_usb_init_qos()
127 *
128 * Based on the same function in drivers/net/irda/irda-usb.c
129 */
130static struct usb_irda_cs_descriptor *
131irda_usb_find_class_desc(struct usb_device *dev, unsigned int ifnum)
132{
133	struct usb_irda_cs_descriptor *desc;
134	int ret;
135
136	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
137	if (!desc)
138		return NULL;
139
140	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
141			USB_REQ_CS_IRDA_GET_CLASS_DESC,
142			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
143			0, ifnum, desc, sizeof(*desc), 1000);
144
145	dbg("%s -  ret=%d", __func__, ret);
146	if (ret < sizeof(*desc)) {
147		dbg("%s - class descriptor read %s (%d)",
148				__func__,
149				(ret < 0) ? "failed" : "too short",
150				ret);
151		goto error;
152	}
153	if (desc->bDescriptorType != USB_DT_CS_IRDA) {
154		dbg("%s - bad class descriptor type", __func__);
155		goto error;
156	}
157
158	irda_usb_dump_class_desc(desc);
159	return desc;
160
161error:
162	kfree(desc);
163	return NULL;
164}
165
166static u8 ir_xbof_change(u8 xbof)
167{
168	u8 result;
169
170	/* reference irda-usb.c */
171	switch (xbof) {
172	case 48:
173		result = 0x10;
174		break;
175	case 28:
176	case 24:
177		result = 0x20;
178		break;
179	default:
180	case 12:
181		result = 0x30;
182		break;
183	case  5:
184	case  6:
185		result = 0x40;
186		break;
187	case  3:
188		result = 0x50;
189		break;
190	case  2:
191		result = 0x60;
192		break;
193	case  1:
194		result = 0x70;
195		break;
196	case  0:
197		result = 0x80;
198		break;
199	}
200
201	return(result);
202}
203
204static int ir_startup(struct usb_serial *serial)
205{
206	struct usb_irda_cs_descriptor *irda_desc;
207
208	irda_desc = irda_usb_find_class_desc(serial->dev, 0);
209	if (!irda_desc) {
210		dev_err(&serial->dev->dev,
211			"IRDA class descriptor not found, device not bound\n");
212		return -ENODEV;
213	}
214
215	dbg("%s - Baud rates supported:%s%s%s%s%s%s%s%s%s",
216		__func__,
217		(irda_desc->wBaudRate & USB_IRDA_BR_2400) ? " 2400" : "",
218		(irda_desc->wBaudRate & USB_IRDA_BR_9600) ? " 9600" : "",
219		(irda_desc->wBaudRate & USB_IRDA_BR_19200) ? " 19200" : "",
220		(irda_desc->wBaudRate & USB_IRDA_BR_38400) ? " 38400" : "",
221		(irda_desc->wBaudRate & USB_IRDA_BR_57600) ? " 57600" : "",
222		(irda_desc->wBaudRate & USB_IRDA_BR_115200) ? " 115200" : "",
223		(irda_desc->wBaudRate & USB_IRDA_BR_576000) ? " 576000" : "",
224		(irda_desc->wBaudRate & USB_IRDA_BR_1152000) ? " 1152000" : "",
225		(irda_desc->wBaudRate & USB_IRDA_BR_4000000) ? " 4000000" : "");
226
227	switch (irda_desc->bmAdditionalBOFs) {
228	case USB_IRDA_AB_48:
229		ir_add_bof = 48;
230		break;
231	case USB_IRDA_AB_24:
232		ir_add_bof = 24;
233		break;
234	case USB_IRDA_AB_12:
235		ir_add_bof = 12;
236		break;
237	case USB_IRDA_AB_6:
238		ir_add_bof = 6;
239		break;
240	case USB_IRDA_AB_3:
241		ir_add_bof = 3;
242		break;
243	case USB_IRDA_AB_2:
244		ir_add_bof = 2;
245		break;
246	case USB_IRDA_AB_1:
247		ir_add_bof = 1;
248		break;
249	case USB_IRDA_AB_0:
250		ir_add_bof = 0;
251		break;
252	default:
253		break;
254	}
255
256	kfree(irda_desc);
257
258	return 0;
259}
260
261static int ir_open(struct tty_struct *tty, struct usb_serial_port *port)
262{
263	int i;
264
265	dbg("%s - port %d", __func__, port->number);
266
267	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
268		port->write_urbs[i]->transfer_flags = URB_ZERO_PACKET;
269
270	/* Start reading from the device */
271	return usb_serial_generic_open(tty, port);
272}
273
274static int ir_prepare_write_buffer(struct usb_serial_port *port,
275						void *dest, size_t size)
276{
277	unsigned char *buf = dest;
278	int count;
279
280	/*
281	 * The first byte of the packet we send to the device contains an
282	 * inbound header which indicates an additional number of BOFs and
283	 * a baud rate change.
284	 *
285	 * See section 5.4.2.2 of the USB IrDA spec.
286	 */
287	*buf = ir_xbof | ir_baud;
288
289	count = kfifo_out_locked(&port->write_fifo, buf + 1, size - 1,
290								&port->lock);
291	return count + 1;
292}
293
294static void ir_process_read_urb(struct urb *urb)
295{
296	struct usb_serial_port *port = urb->context;
297	unsigned char *data = urb->transfer_buffer;
298	struct tty_struct *tty;
299
300	if (!urb->actual_length)
301		return;
302	/*
303	 * The first byte of the packet we get from the device
304	 * contains a busy indicator and baud rate change.
305	 * See section 5.4.1.2 of the USB IrDA spec.
306	 */
307	if (*data & 0x0f)
308		ir_baud = *data & 0x0f;
309
310	if (urb->actual_length == 1)
311		return;
312
313	tty = tty_port_tty_get(&port->port);
314	if (!tty)
315		return;
316	tty_insert_flip_string(tty, data + 1, urb->actual_length - 1);
317	tty_flip_buffer_push(tty);
318	tty_kref_put(tty);
319}
320
321static void ir_set_termios_callback(struct urb *urb)
322{
323	struct usb_serial_port *port = urb->context;
324	int status = urb->status;
325
326	dbg("%s - port %d", __func__, port->number);
327
328	kfree(urb->transfer_buffer);
329
330	if (status)
331		dbg("%s - non-zero urb status: %d", __func__, status);
332}
333
334static void ir_set_termios(struct tty_struct *tty,
335		struct usb_serial_port *port, struct ktermios *old_termios)
336{
337	struct urb *urb;
338	unsigned char *transfer_buffer;
339	int result;
340	speed_t baud;
341	int ir_baud;
342
343	dbg("%s - port %d", __func__, port->number);
344
345	baud = tty_get_baud_rate(tty);
346
347	/*
348	 * FIXME, we should compare the baud request against the
349	 * capability stated in the IR header that we got in the
350	 * startup function.
351	 */
352
353	switch (baud) {
354	case 2400:
355		ir_baud = USB_IRDA_BR_2400;
356		break;
357	case 9600:
358		ir_baud = USB_IRDA_BR_9600;
359		break;
360	case 19200:
361		ir_baud = USB_IRDA_BR_19200;
362		break;
363	case 38400:
364		ir_baud = USB_IRDA_BR_38400;
365		break;
366	case 57600:
367		ir_baud = USB_IRDA_BR_57600;
368		break;
369	case 115200:
370		ir_baud = USB_IRDA_BR_115200;
371		break;
372	case 576000:
373		ir_baud = USB_IRDA_BR_576000;
374		break;
375	case 1152000:
376		ir_baud = USB_IRDA_BR_1152000;
377		break;
378	case 4000000:
379		ir_baud = USB_IRDA_BR_4000000;
380		break;
381	default:
382		ir_baud = USB_IRDA_BR_9600;
383		baud = 9600;
384	}
385
386	if (xbof == -1)
387		ir_xbof = ir_xbof_change(ir_add_bof);
388	else
389		ir_xbof = ir_xbof_change(xbof) ;
390
391	/* Only speed changes are supported */
392	tty_termios_copy_hw(tty->termios, old_termios);
393	tty_encode_baud_rate(tty, baud, baud);
394
395	/*
396	 * send the baud change out on an "empty" data packet
397	 */
398	urb = usb_alloc_urb(0, GFP_KERNEL);
399	if (!urb) {
400		dev_err(&port->dev, "%s - no more urbs\n", __func__);
401		return;
402	}
403	transfer_buffer = kmalloc(1, GFP_KERNEL);
404	if (!transfer_buffer) {
405		dev_err(&port->dev, "%s - out of memory\n", __func__);
406		goto err_buf;
407	}
408
409	*transfer_buffer = ir_xbof | ir_baud;
410
411	usb_fill_bulk_urb(
412		urb,
413		port->serial->dev,
414		usb_sndbulkpipe(port->serial->dev,
415			port->bulk_out_endpointAddress),
416		transfer_buffer,
417		1,
418		ir_set_termios_callback,
419		port);
420
421	urb->transfer_flags = URB_ZERO_PACKET;
422
423	result = usb_submit_urb(urb, GFP_KERNEL);
424	if (result) {
425		dev_err(&port->dev, "%s - failed to submit urb: %d\n",
426							__func__, result);
427		goto err_subm;
428	}
429
430	usb_free_urb(urb);
431
432	return;
433err_subm:
434	kfree(transfer_buffer);
435err_buf:
436	usb_free_urb(urb);
437}
438
439static int __init ir_init(void)
440{
441	int retval;
442
443	if (buffer_size) {
444		ir_device.bulk_in_size = buffer_size;
445		ir_device.bulk_out_size = buffer_size;
446	}
447
448	retval = usb_serial_register(&ir_device);
449	if (retval)
450		goto failed_usb_serial_register;
451
452	retval = usb_register(&ir_driver);
453	if (retval)
454		goto failed_usb_register;
455
456	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
457	       DRIVER_DESC "\n");
458
459	return 0;
460
461failed_usb_register:
462	usb_serial_deregister(&ir_device);
463
464failed_usb_serial_register:
465	return retval;
466}
467
468static void __exit ir_exit(void)
469{
470	usb_deregister(&ir_driver);
471	usb_serial_deregister(&ir_device);
472}
473
474
475module_init(ir_init);
476module_exit(ir_exit);
477
478MODULE_AUTHOR(DRIVER_AUTHOR);
479MODULE_DESCRIPTION(DRIVER_DESC);
480MODULE_LICENSE("GPL");
481
482module_param(debug, bool, S_IRUGO | S_IWUSR);
483MODULE_PARM_DESC(debug, "Debug enabled or not");
484module_param(xbof, int, 0);
485MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
486module_param(buffer_size, int, 0);
487MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
488
489