ir-usb.c revision 7dbe2460989b10644651e779b17b683627feea48 
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};
86
87static struct usb_serial_driver ir_device = {
88	.driver	= {
89		.owner	= THIS_MODULE,
90		.name	= "ir-usb",
91	},
92	.description		= "IR Dongle",
93	.id_table		= ir_id_table,
94	.num_ports		= 1,
95	.set_termios		= ir_set_termios,
96	.attach			= ir_startup,
97	.open			= ir_open,
98	.prepare_write_buffer	= ir_prepare_write_buffer,
99	.process_read_urb	= ir_process_read_urb,
100};
101
102static struct usb_serial_driver * const serial_drivers[] = {
103	&ir_device, NULL
104};
105
106static inline void irda_usb_dump_class_desc(struct usb_irda_cs_descriptor *desc)
107{
108	dbg("bLength=%x", desc->bLength);
109	dbg("bDescriptorType=%x", desc->bDescriptorType);
110	dbg("bcdSpecRevision=%x", __le16_to_cpu(desc->bcdSpecRevision));
111	dbg("bmDataSize=%x", desc->bmDataSize);
112	dbg("bmWindowSize=%x", desc->bmWindowSize);
113	dbg("bmMinTurnaroundTime=%d", desc->bmMinTurnaroundTime);
114	dbg("wBaudRate=%x", __le16_to_cpu(desc->wBaudRate));
115	dbg("bmAdditionalBOFs=%x", desc->bmAdditionalBOFs);
116	dbg("bIrdaRateSniff=%x", desc->bIrdaRateSniff);
117	dbg("bMaxUnicastList=%x", desc->bMaxUnicastList);
118}
119
120/*------------------------------------------------------------------*/
121/*
122 * Function irda_usb_find_class_desc(dev, ifnum)
123 *
124 *    Returns instance of IrDA class descriptor, or NULL if not found
125 *
126 * The class descriptor is some extra info that IrDA USB devices will
127 * offer to us, describing their IrDA characteristics. We will use that in
128 * irda_usb_init_qos()
129 *
130 * Based on the same function in drivers/net/irda/irda-usb.c
131 */
132static struct usb_irda_cs_descriptor *
133irda_usb_find_class_desc(struct usb_device *dev, unsigned int ifnum)
134{
135	struct usb_irda_cs_descriptor *desc;
136	int ret;
137
138	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
139	if (!desc)
140		return NULL;
141
142	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
143			USB_REQ_CS_IRDA_GET_CLASS_DESC,
144			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
145			0, ifnum, desc, sizeof(*desc), 1000);
146
147	dbg("%s -  ret=%d", __func__, ret);
148	if (ret < sizeof(*desc)) {
149		dbg("%s - class descriptor read %s (%d)",
150				__func__,
151				(ret < 0) ? "failed" : "too short",
152				ret);
153		goto error;
154	}
155	if (desc->bDescriptorType != USB_DT_CS_IRDA) {
156		dbg("%s - bad class descriptor type", __func__);
157		goto error;
158	}
159
160	irda_usb_dump_class_desc(desc);
161	return desc;
162
163error:
164	kfree(desc);
165	return NULL;
166}
167
168static u8 ir_xbof_change(u8 xbof)
169{
170	u8 result;
171
172	/* reference irda-usb.c */
173	switch (xbof) {
174	case 48:
175		result = 0x10;
176		break;
177	case 28:
178	case 24:
179		result = 0x20;
180		break;
181	default:
182	case 12:
183		result = 0x30;
184		break;
185	case  5:
186	case  6:
187		result = 0x40;
188		break;
189	case  3:
190		result = 0x50;
191		break;
192	case  2:
193		result = 0x60;
194		break;
195	case  1:
196		result = 0x70;
197		break;
198	case  0:
199		result = 0x80;
200		break;
201	}
202
203	return(result);
204}
205
206static int ir_startup(struct usb_serial *serial)
207{
208	struct usb_irda_cs_descriptor *irda_desc;
209
210	irda_desc = irda_usb_find_class_desc(serial->dev, 0);
211	if (!irda_desc) {
212		dev_err(&serial->dev->dev,
213			"IRDA class descriptor not found, device not bound\n");
214		return -ENODEV;
215	}
216
217	dbg("%s - Baud rates supported:%s%s%s%s%s%s%s%s%s",
218		__func__,
219		(irda_desc->wBaudRate & USB_IRDA_BR_2400) ? " 2400" : "",
220		(irda_desc->wBaudRate & USB_IRDA_BR_9600) ? " 9600" : "",
221		(irda_desc->wBaudRate & USB_IRDA_BR_19200) ? " 19200" : "",
222		(irda_desc->wBaudRate & USB_IRDA_BR_38400) ? " 38400" : "",
223		(irda_desc->wBaudRate & USB_IRDA_BR_57600) ? " 57600" : "",
224		(irda_desc->wBaudRate & USB_IRDA_BR_115200) ? " 115200" : "",
225		(irda_desc->wBaudRate & USB_IRDA_BR_576000) ? " 576000" : "",
226		(irda_desc->wBaudRate & USB_IRDA_BR_1152000) ? " 1152000" : "",
227		(irda_desc->wBaudRate & USB_IRDA_BR_4000000) ? " 4000000" : "");
228
229	switch (irda_desc->bmAdditionalBOFs) {
230	case USB_IRDA_AB_48:
231		ir_add_bof = 48;
232		break;
233	case USB_IRDA_AB_24:
234		ir_add_bof = 24;
235		break;
236	case USB_IRDA_AB_12:
237		ir_add_bof = 12;
238		break;
239	case USB_IRDA_AB_6:
240		ir_add_bof = 6;
241		break;
242	case USB_IRDA_AB_3:
243		ir_add_bof = 3;
244		break;
245	case USB_IRDA_AB_2:
246		ir_add_bof = 2;
247		break;
248	case USB_IRDA_AB_1:
249		ir_add_bof = 1;
250		break;
251	case USB_IRDA_AB_0:
252		ir_add_bof = 0;
253		break;
254	default:
255		break;
256	}
257
258	kfree(irda_desc);
259
260	return 0;
261}
262
263static int ir_open(struct tty_struct *tty, struct usb_serial_port *port)
264{
265	int i;
266
267	dbg("%s - port %d", __func__, port->number);
268
269	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
270		port->write_urbs[i]->transfer_flags = URB_ZERO_PACKET;
271
272	/* Start reading from the device */
273	return usb_serial_generic_open(tty, port);
274}
275
276static int ir_prepare_write_buffer(struct usb_serial_port *port,
277						void *dest, size_t size)
278{
279	unsigned char *buf = dest;
280	int count;
281
282	/*
283	 * The first byte of the packet we send to the device contains an
284	 * inbound header which indicates an additional number of BOFs and
285	 * a baud rate change.
286	 *
287	 * See section 5.4.2.2 of the USB IrDA spec.
288	 */
289	*buf = ir_xbof | ir_baud;
290
291	count = kfifo_out_locked(&port->write_fifo, buf + 1, size - 1,
292								&port->lock);
293	return count + 1;
294}
295
296static void ir_process_read_urb(struct urb *urb)
297{
298	struct usb_serial_port *port = urb->context;
299	unsigned char *data = urb->transfer_buffer;
300	struct tty_struct *tty;
301
302	if (!urb->actual_length)
303		return;
304	/*
305	 * The first byte of the packet we get from the device
306	 * contains a busy indicator and baud rate change.
307	 * See section 5.4.1.2 of the USB IrDA spec.
308	 */
309	if (*data & 0x0f)
310		ir_baud = *data & 0x0f;
311
312	if (urb->actual_length == 1)
313		return;
314
315	tty = tty_port_tty_get(&port->port);
316	if (!tty)
317		return;
318	tty_insert_flip_string(tty, data + 1, urb->actual_length - 1);
319	tty_flip_buffer_push(tty);
320	tty_kref_put(tty);
321}
322
323static void ir_set_termios_callback(struct urb *urb)
324{
325	struct usb_serial_port *port = urb->context;
326	int status = urb->status;
327
328	dbg("%s - port %d", __func__, port->number);
329
330	kfree(urb->transfer_buffer);
331
332	if (status)
333		dbg("%s - non-zero urb status: %d", __func__, status);
334}
335
336static void ir_set_termios(struct tty_struct *tty,
337		struct usb_serial_port *port, struct ktermios *old_termios)
338{
339	struct urb *urb;
340	unsigned char *transfer_buffer;
341	int result;
342	speed_t baud;
343	int ir_baud;
344
345	dbg("%s - port %d", __func__, port->number);
346
347	baud = tty_get_baud_rate(tty);
348
349	/*
350	 * FIXME, we should compare the baud request against the
351	 * capability stated in the IR header that we got in the
352	 * startup function.
353	 */
354
355	switch (baud) {
356	case 2400:
357		ir_baud = USB_IRDA_BR_2400;
358		break;
359	case 9600:
360		ir_baud = USB_IRDA_BR_9600;
361		break;
362	case 19200:
363		ir_baud = USB_IRDA_BR_19200;
364		break;
365	case 38400:
366		ir_baud = USB_IRDA_BR_38400;
367		break;
368	case 57600:
369		ir_baud = USB_IRDA_BR_57600;
370		break;
371	case 115200:
372		ir_baud = USB_IRDA_BR_115200;
373		break;
374	case 576000:
375		ir_baud = USB_IRDA_BR_576000;
376		break;
377	case 1152000:
378		ir_baud = USB_IRDA_BR_1152000;
379		break;
380	case 4000000:
381		ir_baud = USB_IRDA_BR_4000000;
382		break;
383	default:
384		ir_baud = USB_IRDA_BR_9600;
385		baud = 9600;
386	}
387
388	if (xbof == -1)
389		ir_xbof = ir_xbof_change(ir_add_bof);
390	else
391		ir_xbof = ir_xbof_change(xbof) ;
392
393	/* Only speed changes are supported */
394	tty_termios_copy_hw(tty->termios, old_termios);
395	tty_encode_baud_rate(tty, baud, baud);
396
397	/*
398	 * send the baud change out on an "empty" data packet
399	 */
400	urb = usb_alloc_urb(0, GFP_KERNEL);
401	if (!urb) {
402		dev_err(&port->dev, "%s - no more urbs\n", __func__);
403		return;
404	}
405	transfer_buffer = kmalloc(1, GFP_KERNEL);
406	if (!transfer_buffer) {
407		dev_err(&port->dev, "%s - out of memory\n", __func__);
408		goto err_buf;
409	}
410
411	*transfer_buffer = ir_xbof | ir_baud;
412
413	usb_fill_bulk_urb(
414		urb,
415		port->serial->dev,
416		usb_sndbulkpipe(port->serial->dev,
417			port->bulk_out_endpointAddress),
418		transfer_buffer,
419		1,
420		ir_set_termios_callback,
421		port);
422
423	urb->transfer_flags = URB_ZERO_PACKET;
424
425	result = usb_submit_urb(urb, GFP_KERNEL);
426	if (result) {
427		dev_err(&port->dev, "%s - failed to submit urb: %d\n",
428							__func__, result);
429		goto err_subm;
430	}
431
432	usb_free_urb(urb);
433
434	return;
435err_subm:
436	kfree(transfer_buffer);
437err_buf:
438	usb_free_urb(urb);
439}
440
441static int __init ir_init(void)
442{
443	int retval;
444
445	if (buffer_size) {
446		ir_device.bulk_in_size = buffer_size;
447		ir_device.bulk_out_size = buffer_size;
448	}
449
450	retval = usb_serial_register_drivers(&ir_driver, serial_drivers);
451	if (retval == 0)
452		printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
453			       DRIVER_DESC "\n");
454	return retval;
455}
456
457static void __exit ir_exit(void)
458{
459	usb_serial_deregister_drivers(&ir_driver, serial_drivers);
460}
461
462
463module_init(ir_init);
464module_exit(ir_exit);
465
466MODULE_AUTHOR(DRIVER_AUTHOR);
467MODULE_DESCRIPTION(DRIVER_DESC);
468MODULE_LICENSE("GPL");
469
470module_param(debug, bool, S_IRUGO | S_IWUSR);
471MODULE_PARM_DESC(debug, "Debug enabled or not");
472module_param(xbof, int, 0);
473MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
474module_param(buffer_size, int, 0);
475MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
476
477