xref: /openbmc/linux/drivers/usb/serial/ir-usb.c (revision 4d68c05ce11f4cdf6a6392f3a18dc6a985b4d0c4) 
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 
48 static bool debug;
49 
50 /* if overridden by the user, then use their value for the size of the read and
51  * write urbs */
52 static int buffer_size;
53 
54 /* if overridden by the user, then use the specified number of XBOFs */
55 static int xbof = -1;
56 
57 static int  ir_startup (struct usb_serial *serial);
58 static int  ir_open(struct tty_struct *tty, struct usb_serial_port *port);
59 static int ir_prepare_write_buffer(struct usb_serial_port *port,
60 						void *dest, size_t size);
61 static void ir_process_read_urb(struct urb *urb);
62 static 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 */
66 static u8 ir_baud;
67 static u8 ir_xbof;
68 static u8 ir_add_bof;
69 
70 static 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 
78 MODULE_DEVICE_TABLE(usb, ir_id_table);
79 
80 static 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 
88 static 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 
104 static 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  */
130 static struct usb_irda_cs_descriptor *
131 irda_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 
161 error:
162 	kfree(desc);
163 	return NULL;
164 }
165 
166 static 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 
204 static 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 
261 static 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 
274 static 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 
294 static 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 
321 static 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 
334 static 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;
433 err_subm:
434 	kfree(transfer_buffer);
435 err_buf:
436 	usb_free_urb(urb);
437 }
438 
439 static 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 
461 failed_usb_register:
462 	usb_serial_deregister(&ir_device);
463 
464 failed_usb_serial_register:
465 	return retval;
466 }
467 
468 static void __exit ir_exit(void)
469 {
470 	usb_deregister(&ir_driver);
471 	usb_serial_deregister(&ir_device);
472 }
473 
474 
475 module_init(ir_init);
476 module_exit(ir_exit);
477 
478 MODULE_AUTHOR(DRIVER_AUTHOR);
479 MODULE_DESCRIPTION(DRIVER_DESC);
480 MODULE_LICENSE("GPL");
481 
482 module_param(debug, bool, S_IRUGO | S_IWUSR);
483 MODULE_PARM_DESC(debug, "Debug enabled or not");
484 module_param(xbof, int, 0);
485 MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
486 module_param(buffer_size, int, 0);
487 MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
488 
489