ir-usb.c revision 9f857ae922a08a94fe41a649c2d0baa73cd74d2a 
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_serial_driver ir_device = {
81	.driver	= {
82		.owner	= THIS_MODULE,
83		.name	= "ir-usb",
84	},
85	.description		= "IR Dongle",
86	.id_table		= ir_id_table,
87	.num_ports		= 1,
88	.set_termios		= ir_set_termios,
89	.attach			= ir_startup,
90	.open			= ir_open,
91	.prepare_write_buffer	= ir_prepare_write_buffer,
92	.process_read_urb	= ir_process_read_urb,
93};
94
95static struct usb_serial_driver * const serial_drivers[] = {
96	&ir_device, NULL
97};
98
99static inline void irda_usb_dump_class_desc(struct usb_serial *serial,
100					    struct usb_irda_cs_descriptor *desc)
101{
102	struct device *dev = &serial->dev->dev;
103
104	dev_dbg(dev, "bLength=%x\n", desc->bLength);
105	dev_dbg(dev, "bDescriptorType=%x\n", desc->bDescriptorType);
106	dev_dbg(dev, "bcdSpecRevision=%x\n", __le16_to_cpu(desc->bcdSpecRevision));
107	dev_dbg(dev, "bmDataSize=%x\n", desc->bmDataSize);
108	dev_dbg(dev, "bmWindowSize=%x\n", desc->bmWindowSize);
109	dev_dbg(dev, "bmMinTurnaroundTime=%d\n", desc->bmMinTurnaroundTime);
110	dev_dbg(dev, "wBaudRate=%x\n", __le16_to_cpu(desc->wBaudRate));
111	dev_dbg(dev, "bmAdditionalBOFs=%x\n", desc->bmAdditionalBOFs);
112	dev_dbg(dev, "bIrdaRateSniff=%x\n", desc->bIrdaRateSniff);
113	dev_dbg(dev, "bMaxUnicastList=%x\n", desc->bMaxUnicastList);
114}
115
116/*------------------------------------------------------------------*/
117/*
118 * Function irda_usb_find_class_desc(dev, ifnum)
119 *
120 *    Returns instance of IrDA class descriptor, or NULL if not found
121 *
122 * The class descriptor is some extra info that IrDA USB devices will
123 * offer to us, describing their IrDA characteristics. We will use that in
124 * irda_usb_init_qos()
125 *
126 * Based on the same function in drivers/net/irda/irda-usb.c
127 */
128static struct usb_irda_cs_descriptor *
129irda_usb_find_class_desc(struct usb_serial *serial, unsigned int ifnum)
130{
131	struct usb_device *dev = serial->dev;
132	struct usb_irda_cs_descriptor *desc;
133	int ret;
134
135	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
136	if (!desc)
137		return NULL;
138
139	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
140			USB_REQ_CS_IRDA_GET_CLASS_DESC,
141			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
142			0, ifnum, desc, sizeof(*desc), 1000);
143
144	dev_dbg(&serial->dev->dev, "%s -  ret=%d\n", __func__, ret);
145	if (ret < sizeof(*desc)) {
146		dev_dbg(&serial->dev->dev,
147			"%s - class descriptor read %s (%d)\n", __func__,
148			(ret < 0) ? "failed" : "too short", ret);
149		goto error;
150	}
151	if (desc->bDescriptorType != USB_DT_CS_IRDA) {
152		dev_dbg(&serial->dev->dev, "%s - bad class descriptor type\n",
153			__func__);
154		goto error;
155	}
156
157	irda_usb_dump_class_desc(serial, desc);
158	return desc;
159
160error:
161	kfree(desc);
162	return NULL;
163}
164
165static u8 ir_xbof_change(u8 xbof)
166{
167	u8 result;
168
169	/* reference irda-usb.c */
170	switch (xbof) {
171	case 48:
172		result = 0x10;
173		break;
174	case 28:
175	case 24:
176		result = 0x20;
177		break;
178	default:
179	case 12:
180		result = 0x30;
181		break;
182	case  5:
183	case  6:
184		result = 0x40;
185		break;
186	case  3:
187		result = 0x50;
188		break;
189	case  2:
190		result = 0x60;
191		break;
192	case  1:
193		result = 0x70;
194		break;
195	case  0:
196		result = 0x80;
197		break;
198	}
199
200	return(result);
201}
202
203static int ir_startup(struct usb_serial *serial)
204{
205	struct usb_irda_cs_descriptor *irda_desc;
206
207	irda_desc = irda_usb_find_class_desc(serial, 0);
208	if (!irda_desc) {
209		dev_err(&serial->dev->dev,
210			"IRDA class descriptor not found, device not bound\n");
211		return -ENODEV;
212	}
213
214	dev_dbg(&serial->dev->dev,
215		"%s - Baud rates supported:%s%s%s%s%s%s%s%s%s\n",
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	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
266		port->write_urbs[i]->transfer_flags = URB_ZERO_PACKET;
267
268	/* Start reading from the device */
269	return usb_serial_generic_open(tty, port);
270}
271
272static int ir_prepare_write_buffer(struct usb_serial_port *port,
273						void *dest, size_t size)
274{
275	unsigned char *buf = dest;
276	int count;
277
278	/*
279	 * The first byte of the packet we send to the device contains an
280	 * inbound header which indicates an additional number of BOFs and
281	 * a baud rate change.
282	 *
283	 * See section 5.4.2.2 of the USB IrDA spec.
284	 */
285	*buf = ir_xbof | ir_baud;
286
287	count = kfifo_out_locked(&port->write_fifo, buf + 1, size - 1,
288								&port->lock);
289	return count + 1;
290}
291
292static void ir_process_read_urb(struct urb *urb)
293{
294	struct usb_serial_port *port = urb->context;
295	unsigned char *data = urb->transfer_buffer;
296	struct tty_struct *tty;
297
298	if (!urb->actual_length)
299		return;
300	/*
301	 * The first byte of the packet we get from the device
302	 * contains a busy indicator and baud rate change.
303	 * See section 5.4.1.2 of the USB IrDA spec.
304	 */
305	if (*data & 0x0f)
306		ir_baud = *data & 0x0f;
307
308	if (urb->actual_length == 1)
309		return;
310
311	tty = tty_port_tty_get(&port->port);
312	if (!tty)
313		return;
314	tty_insert_flip_string(tty, data + 1, urb->actual_length - 1);
315	tty_flip_buffer_push(tty);
316	tty_kref_put(tty);
317}
318
319static void ir_set_termios_callback(struct urb *urb)
320{
321	kfree(urb->transfer_buffer);
322
323	if (urb->status)
324		dev_dbg(&urb->dev->dev, "%s - non-zero urb status: %d\n",
325			__func__, urb->status);
326}
327
328static void ir_set_termios(struct tty_struct *tty,
329		struct usb_serial_port *port, struct ktermios *old_termios)
330{
331	struct urb *urb;
332	unsigned char *transfer_buffer;
333	int result;
334	speed_t baud;
335	int ir_baud;
336
337	baud = tty_get_baud_rate(tty);
338
339	/*
340	 * FIXME, we should compare the baud request against the
341	 * capability stated in the IR header that we got in the
342	 * startup function.
343	 */
344
345	switch (baud) {
346	case 2400:
347		ir_baud = USB_IRDA_BR_2400;
348		break;
349	case 9600:
350		ir_baud = USB_IRDA_BR_9600;
351		break;
352	case 19200:
353		ir_baud = USB_IRDA_BR_19200;
354		break;
355	case 38400:
356		ir_baud = USB_IRDA_BR_38400;
357		break;
358	case 57600:
359		ir_baud = USB_IRDA_BR_57600;
360		break;
361	case 115200:
362		ir_baud = USB_IRDA_BR_115200;
363		break;
364	case 576000:
365		ir_baud = USB_IRDA_BR_576000;
366		break;
367	case 1152000:
368		ir_baud = USB_IRDA_BR_1152000;
369		break;
370	case 4000000:
371		ir_baud = USB_IRDA_BR_4000000;
372		break;
373	default:
374		ir_baud = USB_IRDA_BR_9600;
375		baud = 9600;
376	}
377
378	if (xbof == -1)
379		ir_xbof = ir_xbof_change(ir_add_bof);
380	else
381		ir_xbof = ir_xbof_change(xbof) ;
382
383	/* Only speed changes are supported */
384	tty_termios_copy_hw(tty->termios, old_termios);
385	tty_encode_baud_rate(tty, baud, baud);
386
387	/*
388	 * send the baud change out on an "empty" data packet
389	 */
390	urb = usb_alloc_urb(0, GFP_KERNEL);
391	if (!urb) {
392		dev_err(&port->dev, "%s - no more urbs\n", __func__);
393		return;
394	}
395	transfer_buffer = kmalloc(1, GFP_KERNEL);
396	if (!transfer_buffer) {
397		dev_err(&port->dev, "%s - out of memory\n", __func__);
398		goto err_buf;
399	}
400
401	*transfer_buffer = ir_xbof | ir_baud;
402
403	usb_fill_bulk_urb(
404		urb,
405		port->serial->dev,
406		usb_sndbulkpipe(port->serial->dev,
407			port->bulk_out_endpointAddress),
408		transfer_buffer,
409		1,
410		ir_set_termios_callback,
411		port);
412
413	urb->transfer_flags = URB_ZERO_PACKET;
414
415	result = usb_submit_urb(urb, GFP_KERNEL);
416	if (result) {
417		dev_err(&port->dev, "%s - failed to submit urb: %d\n",
418							__func__, result);
419		goto err_subm;
420	}
421
422	usb_free_urb(urb);
423
424	return;
425err_subm:
426	kfree(transfer_buffer);
427err_buf:
428	usb_free_urb(urb);
429}
430
431static int __init ir_init(void)
432{
433	int retval;
434
435	if (buffer_size) {
436		ir_device.bulk_in_size = buffer_size;
437		ir_device.bulk_out_size = buffer_size;
438	}
439
440	retval = usb_serial_register_drivers(serial_drivers, KBUILD_MODNAME, ir_id_table);
441	if (retval == 0)
442		printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
443			       DRIVER_DESC "\n");
444	return retval;
445}
446
447static void __exit ir_exit(void)
448{
449	usb_serial_deregister_drivers(serial_drivers);
450}
451
452
453module_init(ir_init);
454module_exit(ir_exit);
455
456MODULE_AUTHOR(DRIVER_AUTHOR);
457MODULE_DESCRIPTION(DRIVER_DESC);
458MODULE_LICENSE("GPL");
459
460module_param(debug, bool, S_IRUGO | S_IWUSR);
461MODULE_PARM_DESC(debug, "Debug enabled or not");
462module_param(xbof, int, 0);
463MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
464module_param(buffer_size, int, 0);
465MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
466
467