xref: /openbmc/linux/drivers/media/rc/ttusbir.c (revision f7777dcc)
1 /*
2  * TechnoTrend USB IR Receiver
3  *
4  * Copyright (C) 2012 Sean Young <sean@mess.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19  */
20 
21 #include <linux/module.h>
22 #include <linux/usb.h>
23 #include <linux/usb/input.h>
24 #include <linux/slab.h>
25 #include <linux/leds.h>
26 #include <media/rc-core.h>
27 
28 #define DRIVER_NAME	"ttusbir"
29 #define DRIVER_DESC	"TechnoTrend USB IR Receiver"
30 /*
31  * The Windows driver uses 8 URBS, the original lirc drivers has a
32  * configurable amount (2 default, 4 max). This device generates about 125
33  * messages per second (!), whether IR is idle or not.
34  */
35 #define NUM_URBS	4
36 #define NS_PER_BYTE	62500
37 #define NS_PER_BIT	(NS_PER_BYTE/8)
38 
39 struct ttusbir {
40 	struct rc_dev *rc;
41 	struct device *dev;
42 	struct usb_device *udev;
43 
44 	struct urb *urb[NUM_URBS];
45 
46 	struct led_classdev led;
47 	struct urb *bulk_urb;
48 	uint8_t bulk_buffer[5];
49 	int bulk_out_endp, iso_in_endp;
50 	bool led_on, is_led_on;
51 	atomic_t led_complete;
52 
53 	char phys[64];
54 };
55 
56 static enum led_brightness ttusbir_brightness_get(struct led_classdev *led_dev)
57 {
58 	struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
59 
60 	return tt->led_on ? LED_FULL : LED_OFF;
61 }
62 
63 static void ttusbir_set_led(struct ttusbir *tt)
64 {
65 	int ret;
66 
67 	smp_mb();
68 
69 	if (tt->led_on != tt->is_led_on && tt->udev &&
70 				atomic_add_unless(&tt->led_complete, 1, 1)) {
71 		tt->bulk_buffer[4] = tt->is_led_on = tt->led_on;
72 		ret = usb_submit_urb(tt->bulk_urb, GFP_ATOMIC);
73 		if (ret) {
74 			dev_warn(tt->dev, "failed to submit bulk urb: %d\n",
75 									ret);
76 			atomic_dec(&tt->led_complete);
77 		}
78 	}
79 }
80 
81 static void ttusbir_brightness_set(struct led_classdev *led_dev, enum
82 						led_brightness brightness)
83 {
84 	struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
85 
86 	tt->led_on = brightness != LED_OFF;
87 
88 	ttusbir_set_led(tt);
89 }
90 
91 /*
92  * The urb cannot be reused until the urb completes
93  */
94 static void ttusbir_bulk_complete(struct urb *urb)
95 {
96 	struct ttusbir *tt = urb->context;
97 
98 	atomic_dec(&tt->led_complete);
99 
100 	switch (urb->status) {
101 	case 0:
102 		break;
103 	case -ECONNRESET:
104 	case -ENOENT:
105 	case -ESHUTDOWN:
106 		usb_unlink_urb(urb);
107 		return;
108 	case -EPIPE:
109 	default:
110 		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
111 		break;
112 	}
113 
114 	ttusbir_set_led(tt);
115 }
116 
117 /*
118  * The data is one bit per sample, a set bit signifying silence and samples
119  * being MSB first. Bit 0 can contain garbage so take it to be whatever
120  * bit 1 is, so we don't have unexpected edges.
121  */
122 static void ttusbir_process_ir_data(struct ttusbir *tt, uint8_t *buf)
123 {
124 	struct ir_raw_event rawir;
125 	unsigned i, v, b;
126 	bool event = false;
127 
128 	init_ir_raw_event(&rawir);
129 
130 	for (i = 0; i < 128; i++) {
131 		v = buf[i] & 0xfe;
132 		switch (v) {
133 		case 0xfe:
134 			rawir.pulse = false;
135 			rawir.duration = NS_PER_BYTE;
136 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
137 				event = true;
138 			break;
139 		case 0:
140 			rawir.pulse = true;
141 			rawir.duration = NS_PER_BYTE;
142 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
143 				event = true;
144 			break;
145 		default:
146 			/* one edge per byte */
147 			if (v & 2) {
148 				b = ffz(v | 1);
149 				rawir.pulse = true;
150 			} else {
151 				b = ffs(v) - 1;
152 				rawir.pulse = false;
153 			}
154 
155 			rawir.duration = NS_PER_BIT * (8 - b);
156 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
157 				event = true;
158 
159 			rawir.pulse = !rawir.pulse;
160 			rawir.duration = NS_PER_BIT * b;
161 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
162 				event = true;
163 			break;
164 		}
165 	}
166 
167 	/* don't wakeup when there's nothing to do */
168 	if (event)
169 		ir_raw_event_handle(tt->rc);
170 }
171 
172 static void ttusbir_urb_complete(struct urb *urb)
173 {
174 	struct ttusbir *tt = urb->context;
175 	int rc;
176 
177 	switch (urb->status) {
178 	case 0:
179 		ttusbir_process_ir_data(tt, urb->transfer_buffer);
180 		break;
181 	case -ECONNRESET:
182 	case -ENOENT:
183 	case -ESHUTDOWN:
184 		usb_unlink_urb(urb);
185 		return;
186 	case -EPIPE:
187 	default:
188 		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
189 		break;
190 	}
191 
192 	rc = usb_submit_urb(urb, GFP_ATOMIC);
193 	if (rc && rc != -ENODEV)
194 		dev_warn(tt->dev, "failed to resubmit urb: %d\n", rc);
195 }
196 
197 static int ttusbir_probe(struct usb_interface *intf,
198 			 const struct usb_device_id *id)
199 {
200 	struct ttusbir *tt;
201 	struct usb_interface_descriptor *idesc;
202 	struct usb_endpoint_descriptor *desc;
203 	struct rc_dev *rc;
204 	int i, j, ret;
205 	int altsetting = -1;
206 
207 	tt = kzalloc(sizeof(*tt), GFP_KERNEL);
208 	rc = rc_allocate_device();
209 	if (!tt || !rc) {
210 		ret = -ENOMEM;
211 		goto out;
212 	}
213 
214 	/* find the correct alt setting */
215 	for (i = 0; i < intf->num_altsetting && altsetting == -1; i++) {
216 		int max_packet, bulk_out_endp = -1, iso_in_endp = -1;
217 
218 		idesc = &intf->altsetting[i].desc;
219 
220 		for (j = 0; j < idesc->bNumEndpoints; j++) {
221 			desc = &intf->altsetting[i].endpoint[j].desc;
222 			max_packet = le16_to_cpu(desc->wMaxPacketSize);
223 			if (usb_endpoint_dir_in(desc) &&
224 					usb_endpoint_xfer_isoc(desc) &&
225 					max_packet == 0x10)
226 				iso_in_endp = j;
227 			else if (usb_endpoint_dir_out(desc) &&
228 					usb_endpoint_xfer_bulk(desc) &&
229 					max_packet == 0x20)
230 				bulk_out_endp = j;
231 
232 			if (bulk_out_endp != -1 && iso_in_endp != -1) {
233 				tt->bulk_out_endp = bulk_out_endp;
234 				tt->iso_in_endp = iso_in_endp;
235 				altsetting = i;
236 				break;
237 			}
238 		}
239 	}
240 
241 	if (altsetting == -1) {
242 		dev_err(&intf->dev, "cannot find expected altsetting\n");
243 		ret = -ENODEV;
244 		goto out;
245 	}
246 
247 	tt->dev = &intf->dev;
248 	tt->udev = interface_to_usbdev(intf);
249 	tt->rc = rc;
250 
251 	ret = usb_set_interface(tt->udev, 0, altsetting);
252 	if (ret)
253 		goto out;
254 
255 	for (i = 0; i < NUM_URBS; i++) {
256 		struct urb *urb = usb_alloc_urb(8, GFP_KERNEL);
257 		void *buffer;
258 
259 		if (!urb) {
260 			ret = -ENOMEM;
261 			goto out;
262 		}
263 
264 		urb->dev = tt->udev;
265 		urb->context = tt;
266 		urb->pipe = usb_rcvisocpipe(tt->udev, tt->iso_in_endp);
267 		urb->interval = 1;
268 		buffer = usb_alloc_coherent(tt->udev, 128, GFP_KERNEL,
269 						&urb->transfer_dma);
270 		if (!buffer) {
271 			usb_free_urb(urb);
272 			ret = -ENOMEM;
273 			goto out;
274 		}
275 		urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP | URB_ISO_ASAP;
276 		urb->transfer_buffer = buffer;
277 		urb->complete = ttusbir_urb_complete;
278 		urb->number_of_packets = 8;
279 		urb->transfer_buffer_length = 128;
280 
281 		for (j = 0; j < 8; j++) {
282 			urb->iso_frame_desc[j].offset = j * 16;
283 			urb->iso_frame_desc[j].length = 16;
284 		}
285 
286 		tt->urb[i] = urb;
287 	}
288 
289 	tt->bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
290 	if (!tt->bulk_urb) {
291 		ret = -ENOMEM;
292 		goto out;
293 	}
294 
295 	tt->bulk_buffer[0] = 0xaa;
296 	tt->bulk_buffer[1] = 0x01;
297 	tt->bulk_buffer[2] = 0x05;
298 	tt->bulk_buffer[3] = 0x01;
299 
300 	usb_fill_bulk_urb(tt->bulk_urb, tt->udev, usb_sndbulkpipe(tt->udev,
301 		tt->bulk_out_endp), tt->bulk_buffer, sizeof(tt->bulk_buffer),
302 						ttusbir_bulk_complete, tt);
303 
304 	tt->led.name = "ttusbir:green:power";
305 	tt->led.default_trigger = "rc-feedback";
306 	tt->led.brightness_set = ttusbir_brightness_set;
307 	tt->led.brightness_get = ttusbir_brightness_get;
308 	tt->is_led_on = tt->led_on = true;
309 	atomic_set(&tt->led_complete, 0);
310 	ret = led_classdev_register(&intf->dev, &tt->led);
311 	if (ret)
312 		goto out;
313 
314 	usb_make_path(tt->udev, tt->phys, sizeof(tt->phys));
315 
316 	rc->input_name = DRIVER_DESC;
317 	rc->input_phys = tt->phys;
318 	usb_to_input_id(tt->udev, &rc->input_id);
319 	rc->dev.parent = &intf->dev;
320 	rc->driver_type = RC_DRIVER_IR_RAW;
321 	rc->allowed_protos = RC_BIT_ALL;
322 	rc->priv = tt;
323 	rc->driver_name = DRIVER_NAME;
324 	rc->map_name = RC_MAP_TT_1500;
325 	rc->timeout = MS_TO_NS(100);
326 	/*
327 	 * The precision is NS_PER_BIT, but since every 8th bit can be
328 	 * overwritten with garbage the accuracy is at best 2 * NS_PER_BIT.
329 	 */
330 	rc->rx_resolution = NS_PER_BIT;
331 
332 	ret = rc_register_device(rc);
333 	if (ret) {
334 		dev_err(&intf->dev, "failed to register rc device %d\n", ret);
335 		goto out2;
336 	}
337 
338 	usb_set_intfdata(intf, tt);
339 
340 	for (i = 0; i < NUM_URBS; i++) {
341 		ret = usb_submit_urb(tt->urb[i], GFP_KERNEL);
342 		if (ret) {
343 			dev_err(tt->dev, "failed to submit urb %d\n", ret);
344 			goto out3;
345 		}
346 	}
347 
348 	return 0;
349 out3:
350 	rc_unregister_device(rc);
351 	rc = NULL;
352 out2:
353 	led_classdev_unregister(&tt->led);
354 out:
355 	if (tt) {
356 		for (i = 0; i < NUM_URBS && tt->urb[i]; i++) {
357 			struct urb *urb = tt->urb[i];
358 
359 			usb_kill_urb(urb);
360 			usb_free_coherent(tt->udev, 128, urb->transfer_buffer,
361 							urb->transfer_dma);
362 			usb_free_urb(urb);
363 		}
364 		usb_kill_urb(tt->bulk_urb);
365 		usb_free_urb(tt->bulk_urb);
366 		kfree(tt);
367 	}
368 	rc_free_device(rc);
369 
370 	return ret;
371 }
372 
373 static void ttusbir_disconnect(struct usb_interface *intf)
374 {
375 	struct ttusbir *tt = usb_get_intfdata(intf);
376 	struct usb_device *udev = tt->udev;
377 	int i;
378 
379 	tt->udev = NULL;
380 
381 	rc_unregister_device(tt->rc);
382 	led_classdev_unregister(&tt->led);
383 	for (i = 0; i < NUM_URBS; i++) {
384 		usb_kill_urb(tt->urb[i]);
385 		usb_free_coherent(udev, 128, tt->urb[i]->transfer_buffer,
386 						tt->urb[i]->transfer_dma);
387 		usb_free_urb(tt->urb[i]);
388 	}
389 	usb_kill_urb(tt->bulk_urb);
390 	usb_free_urb(tt->bulk_urb);
391 	usb_set_intfdata(intf, NULL);
392 	kfree(tt);
393 }
394 
395 static int ttusbir_suspend(struct usb_interface *intf, pm_message_t message)
396 {
397 	struct ttusbir *tt = usb_get_intfdata(intf);
398 	int i;
399 
400 	for (i = 0; i < NUM_URBS; i++)
401 		usb_kill_urb(tt->urb[i]);
402 
403 	led_classdev_suspend(&tt->led);
404 	usb_kill_urb(tt->bulk_urb);
405 
406 	return 0;
407 }
408 
409 static int ttusbir_resume(struct usb_interface *intf)
410 {
411 	struct ttusbir *tt = usb_get_intfdata(intf);
412 	int i, rc;
413 
414 	tt->is_led_on = true;
415 	led_classdev_resume(&tt->led);
416 
417 	for (i = 0; i < NUM_URBS; i++) {
418 		rc = usb_submit_urb(tt->urb[i], GFP_KERNEL);
419 		if (rc) {
420 			dev_warn(tt->dev, "failed to submit urb: %d\n", rc);
421 			break;
422 		}
423 	}
424 
425 	return rc;
426 }
427 
428 static const struct usb_device_id ttusbir_table[] = {
429 	{ USB_DEVICE(0x0b48, 0x2003) },
430 	{ }
431 };
432 
433 static struct usb_driver ttusbir_driver = {
434 	.name = DRIVER_NAME,
435 	.id_table = ttusbir_table,
436 	.probe = ttusbir_probe,
437 	.suspend = ttusbir_suspend,
438 	.resume = ttusbir_resume,
439 	.reset_resume = ttusbir_resume,
440 	.disconnect = ttusbir_disconnect,
441 };
442 
443 module_usb_driver(ttusbir_driver);
444 
445 MODULE_DESCRIPTION(DRIVER_DESC);
446 MODULE_AUTHOR("Sean Young <sean@mess.org>");
447 MODULE_LICENSE("GPL");
448 MODULE_DEVICE_TABLE(usb, ttusbir_table);
449 
450