aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/serial/ir-usb.c
blob: 7643716b52997e233990fd0217003ddb42a31e8a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
// SPDX-License-Identifier: GPL-2.0+
/*
 * USB IR Dongle driver
 *
 *	Copyright (C) 2001-2002	Greg Kroah-Hartman (greg@kroah.com)
 *	Copyright (C) 2002	Gary Brubaker (xavyer@ix.netcom.com)
 *	Copyright (C) 2010	Johan Hovold (jhovold@gmail.com)
 *
 * This driver allows a USB IrDA device to be used as a "dumb" serial device.
 * This can be useful if you do not have access to a full IrDA stack on the
 * other side of the connection.  If you do have an IrDA stack on both devices,
 * please use the usb-irda driver, as it contains the proper error checking and
 * other goodness of a full IrDA stack.
 *
 * Portions of this driver were taken from drivers/net/irda/irda-usb.c, which
 * was written by Roman Weissgaerber <weissg@vienna.at>, Dag Brattli
 * <dag@brattli.net>, and Jean Tourrilhes <jt@hpl.hp.com>
 *
 * See Documentation/usb/usb-serial.txt for more information on using this
 * driver
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/usb/irda.h>

#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Johan Hovold <jhovold@gmail.com>"
#define DRIVER_DESC "USB IR Dongle driver"

/* if overridden by the user, then use their value for the size of the read and
 * write urbs */
static int buffer_size;

/* if overridden by the user, then use the specified number of XBOFs */
static int xbof = -1;

static int  ir_startup (struct usb_serial *serial);
static int  ir_open(struct tty_struct *tty, struct usb_serial_port *port);
static int ir_prepare_write_buffer(struct usb_serial_port *port,
						void *dest, size_t size);
static void ir_process_read_urb(struct urb *urb);
static void ir_set_termios(struct tty_struct *tty,
		struct usb_serial_port *port, struct ktermios *old_termios);

/* Not that this lot means you can only have one per system */
static u8 ir_baud;
static u8 ir_xbof;
static u8 ir_add_bof;

static const struct usb_device_id ir_id_table[] = {
	{ USB_DEVICE(0x050f, 0x0180) },		/* KC Technology, KC-180 */
	{ USB_DEVICE(0x08e9, 0x0100) },		/* XTNDAccess */
	{ USB_DEVICE(0x09c4, 0x0011) },		/* ACTiSys ACT-IR2000U */
	{ USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, USB_SUBCLASS_IRDA, 0) },
	{ }					/* Terminating entry */
};

MODULE_DEVICE_TABLE(usb, ir_id_table);

static struct usb_serial_driver ir_device = {
	.driver	= {
		.owner	= THIS_MODULE,
		.name	= "ir-usb",
	},
	.description		= "IR Dongle",
	.id_table		= ir_id_table,
	.num_ports		= 1,
	.set_termios		= ir_set_termios,
	.attach			= ir_startup,
	.open			= ir_open,
	.prepare_write_buffer	= ir_prepare_write_buffer,
	.process_read_urb	= ir_process_read_urb,
};

static struct usb_serial_driver * const serial_drivers[] = {
	&ir_device, NULL
};

static inline void irda_usb_dump_class_desc(struct usb_serial *serial,
					    struct usb_irda_cs_descriptor *desc)
{
	struct device *dev = &serial->dev->dev;

	dev_dbg(dev, "bLength=%x\n", desc->bLength);
	dev_dbg(dev, "bDescriptorType=%x\n", desc->bDescriptorType);
	dev_dbg(dev, "bcdSpecRevision=%x\n", __le16_to_cpu(desc->bcdSpecRevision));
	dev_dbg(dev, "bmDataSize=%x\n", desc->bmDataSize);
	dev_dbg(dev, "bmWindowSize=%x\n", desc->bmWindowSize);
	dev_dbg(dev, "bmMinTurnaroundTime=%d\n", desc->bmMinTurnaroundTime);
	dev_dbg(dev, "wBaudRate=%x\n", __le16_to_cpu(desc->wBaudRate));
	dev_dbg(dev, "bmAdditionalBOFs=%x\n", desc->bmAdditionalBOFs);
	dev_dbg(dev, "bIrdaRateSniff=%x\n", desc->bIrdaRateSniff);
	dev_dbg(dev, "bMaxUnicastList=%x\n", desc->bMaxUnicastList);
}

/*------------------------------------------------------------------*/
/*
 * Function irda_usb_find_class_desc(dev, ifnum)
 *
 *    Returns instance of IrDA class descriptor, or NULL if not found
 *
 * The class descriptor is some extra info that IrDA USB devices will
 * offer to us, describing their IrDA characteristics. We will use that in
 * irda_usb_init_qos()
 *
 * Based on the same function in drivers/net/irda/irda-usb.c
 */
static struct usb_irda_cs_descriptor *
irda_usb_find_class_desc(struct usb_serial *serial, unsigned int ifnum)
{
	struct usb_device *dev = serial->dev;
	struct usb_irda_cs_descriptor *desc;
	int ret;

	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
	if (!desc)
		return NULL;

	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
			USB_REQ_CS_IRDA_GET_CLASS_DESC,
			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
			0, ifnum, desc, sizeof(*desc), 1000);

	dev_dbg(&serial->dev->dev, "%s -  ret=%d\n", __func__, ret);
	if (ret < (int)sizeof(*desc)) {
		dev_dbg(&serial->dev->dev,
			"%s - class descriptor read %s (%d)\n", __func__,
			(ret < 0) ? "failed" : "too short", ret);
		goto error;
	}
	if (desc->bDescriptorType != USB_DT_CS_IRDA) {
		dev_dbg(&serial->dev->dev, "%s - bad class descriptor type\n",
			__func__);
		goto error;
	}

	irda_usb_dump_class_desc(serial, desc);
	return desc;

error:
	kfree(desc);
	return NULL;
}

static u8 ir_xbof_change(u8 xbof)
{
	u8 result;

	/* reference irda-usb.c */
	switch (xbof) {
	case 48:
		result = 0x10;
		break;
	case 28:
	case 24:
		result = 0x20;
		break;
	default:
	case 12:
		result = 0x30;
		break;
	case  5:
	case  6:
		result = 0x40;
		break;
	case  3:
		result = 0x50;
		break;
	case  2:
		result = 0x60;
		break;
	case  1:
		result = 0x70;
		break;
	case  0:
		result = 0x80;
		break;
	}

	return(result);
}

static int ir_startup(struct usb_serial *serial)
{
	struct usb_irda_cs_descriptor *irda_desc;
	int rates;

	irda_desc = irda_usb_find_class_desc(serial, 0);
	if (!irda_desc) {
		dev_err(&serial->dev->dev,
			"IRDA class descriptor not found, device not bound\n");
		return -ENODEV;
	}

	rates = le16_to_cpu(irda_desc->wBaudRate);

	dev_dbg(&serial->dev->dev,
		"%s - Baud rates supported:%s%s%s%s%s%s%s%s%s\n",
		__func__,
		(rates & USB_IRDA_BR_2400) ? " 2400" : "",
		(rates & USB_IRDA_BR_9600) ? " 9600" : "",
		(rates & USB_IRDA_BR_19200) ? " 19200" : "",
		(rates & USB_IRDA_BR_38400) ? " 38400" : "",
		(rates & USB_IRDA_BR_57600) ? " 57600" : "",
		(rates & USB_IRDA_BR_115200) ? " 115200" : "",
		(rates & USB_IRDA_BR_576000) ? " 576000" : "",
		(rates & USB_IRDA_BR_1152000) ? " 1152000" : "",
		(rates & USB_IRDA_BR_4000000) ? " 4000000" : "");

	switch (irda_desc->bmAdditionalBOFs) {
	case USB_IRDA_AB_48:
		ir_add_bof = 48;
		break;
	case USB_IRDA_AB_24:
		ir_add_bof = 24;
		break;
	case USB_IRDA_AB_12:
		ir_add_bof = 12;
		break;
	case USB_IRDA_AB_6:
		ir_add_bof = 6;
		break;
	case USB_IRDA_AB_3:
		ir_add_bof = 3;
		break;
	case USB_IRDA_AB_2:
		ir_add_bof = 2;
		break;
	case USB_IRDA_AB_1:
		ir_add_bof = 1;
		break;
	case USB_IRDA_AB_0:
		ir_add_bof = 0;
		break;
	default:
		break;
	}

	kfree(irda_desc);

	return 0;
}

static int ir_open(struct tty_struct *tty, struct usb_serial_port *port)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
		port->write_urbs[i]->transfer_flags = URB_ZERO_PACKET;

	/* Start reading from the device */
	return usb_serial_generic_open(tty, port);
}

static int ir_prepare_write_buffer(struct usb_serial_port *port,
						void *dest, size_t size)
{
	unsigned char *buf = dest;
	int count;

	/*
	 * The first byte of the packet we send to the device contains an
	 * inbound header which indicates an additional number of BOFs and
	 * a baud rate change.
	 *
	 * See section 5.4.2.2 of the USB IrDA spec.
	 */
	*buf = ir_xbof | ir_baud;

	count = kfifo_out_locked(&port->write_fifo, buf + 1, size - 1,
								&port->lock);
	return count + 1;
}

static void ir_process_read_urb(struct urb *urb)
{
	struct usb_serial_port *port = urb->context;
	unsigned char *data = urb->transfer_buffer;

	if (!urb->actual_length)
		return;
	/*
	 * The first byte of the packet we get from the device
	 * contains a busy indicator and baud rate change.
	 * See section 5.4.1.2 of the USB IrDA spec.
	 */
	if (*data & 0x0f)
		ir_baud = *data & 0x0f;

	if (urb->actual_length == 1)
		return;

	tty_insert_flip_string(&port->port, data + 1, urb->actual_length - 1);
	tty_flip_buffer_push(&port->port);
}

static void ir_set_termios_callback(struct urb *urb)
{
	kfree(urb->transfer_buffer);

	if (urb->status)
		dev_dbg(&urb->dev->dev, "%s - non-zero urb status: %d\n",
			__func__, urb->status);
}

static void ir_set_termios(struct tty_struct *tty,
		struct usb_serial_port *port, struct ktermios *old_termios)
{
	struct urb *urb;
	unsigned char *transfer_buffer;
	int result;
	speed_t baud;
	int ir_baud;

	baud = tty_get_baud_rate(tty);

	/*
	 * FIXME, we should compare the baud request against the
	 * capability stated in the IR header that we got in the
	 * startup function.
	 */

	switch (baud) {
	case 2400:
		ir_baud = USB_IRDA_BR_2400;
		break;
	case 9600:
		ir_baud = USB_IRDA_BR_9600;
		break;
	case 19200:
		ir_baud = USB_IRDA_BR_19200;
		break;
	case 38400:
		ir_baud = USB_IRDA_BR_38400;
		break;
	case 57600:
		ir_baud = USB_IRDA_BR_57600;
		break;
	case 115200:
		ir_baud = USB_IRDA_BR_115200;
		break;
	case 576000:
		ir_baud = USB_IRDA_BR_576000;
		break;
	case 1152000:
		ir_baud = USB_IRDA_BR_1152000;
		break;
	case 4000000:
		ir_baud = USB_IRDA_BR_4000000;
		break;
	default:
		ir_baud = USB_IRDA_BR_9600;
		baud = 9600;
	}

	if (xbof == -1)
		ir_xbof = ir_xbof_change(ir_add_bof);
	else
		ir_xbof = ir_xbof_change(xbof) ;

	/* Only speed changes are supported */
	tty_termios_copy_hw(&tty->termios, old_termios);
	tty_encode_baud_rate(tty, baud, baud);

	/*
	 * send the baud change out on an "empty" data packet
	 */
	urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!urb)
		return;

	transfer_buffer = kmalloc(1, GFP_KERNEL);
	if (!transfer_buffer)
		goto err_buf;

	*transfer_buffer = ir_xbof | ir_baud;

	usb_fill_bulk_urb(
		urb,
		port->serial->dev,
		usb_sndbulkpipe(port->serial->dev,
			port->bulk_out_endpointAddress),
		transfer_buffer,
		1,
		ir_set_termios_callback,
		port);

	urb->transfer_flags = URB_ZERO_PACKET;

	result = usb_submit_urb(urb, GFP_KERNEL);
	if (result) {
		dev_err(&port->dev, "%s - failed to submit urb: %d\n",
							__func__, result);
		goto err_subm;
	}

	usb_free_urb(urb);

	return;
err_subm:
	kfree(transfer_buffer);
err_buf:
	usb_free_urb(urb);
}

static int __init ir_init(void)
{
	if (buffer_size) {
		ir_device.bulk_in_size = buffer_size;
		ir_device.bulk_out_size = buffer_size;
	}

	return usb_serial_register_drivers(serial_drivers, KBUILD_MODNAME, ir_id_table);
}

static void __exit ir_exit(void)
{
	usb_serial_deregister_drivers(serial_drivers);
}


module_init(ir_init);
module_exit(ir_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

module_param(xbof, int, 0);
MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
module_param(buffer_size, int, 0);
MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");