xref: /openbmc/linux/drivers/media/rc/ttusbir.c (revision ef2b56df)
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 
17 #include <linux/module.h>
18 #include <linux/usb.h>
19 #include <linux/usb/input.h>
20 #include <linux/slab.h>
21 #include <linux/leds.h>
22 #include <media/rc-core.h>
23 
24 #define DRIVER_NAME	"ttusbir"
25 #define DRIVER_DESC	"TechnoTrend USB IR Receiver"
26 /*
27  * The Windows driver uses 8 URBS, the original lirc drivers has a
28  * configurable amount (2 default, 4 max). This device generates about 125
29  * messages per second (!), whether IR is idle or not.
30  */
31 #define NUM_URBS	4
32 #define NS_PER_BYTE	62500
33 #define NS_PER_BIT	(NS_PER_BYTE/8)
34 
35 struct ttusbir {
36 	struct rc_dev *rc;
37 	struct device *dev;
38 	struct usb_device *udev;
39 
40 	struct urb *urb[NUM_URBS];
41 
42 	struct led_classdev led;
43 	struct urb *bulk_urb;
44 	uint8_t bulk_buffer[5];
45 	int bulk_out_endp, iso_in_endp;
46 	bool led_on, is_led_on;
47 	atomic_t led_complete;
48 
49 	char phys[64];
50 };
51 
52 static enum led_brightness ttusbir_brightness_get(struct led_classdev *led_dev)
53 {
54 	struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
55 
56 	return tt->led_on ? LED_FULL : LED_OFF;
57 }
58 
59 static void ttusbir_set_led(struct ttusbir *tt)
60 {
61 	int ret;
62 
63 	smp_mb();
64 
65 	if (tt->led_on != tt->is_led_on && tt->udev &&
66 				atomic_add_unless(&tt->led_complete, 1, 1)) {
67 		tt->bulk_buffer[4] = tt->is_led_on = tt->led_on;
68 		ret = usb_submit_urb(tt->bulk_urb, GFP_ATOMIC);
69 		if (ret) {
70 			dev_warn(tt->dev, "failed to submit bulk urb: %d\n",
71 									ret);
72 			atomic_dec(&tt->led_complete);
73 		}
74 	}
75 }
76 
77 static void ttusbir_brightness_set(struct led_classdev *led_dev, enum
78 						led_brightness brightness)
79 {
80 	struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
81 
82 	tt->led_on = brightness != LED_OFF;
83 
84 	ttusbir_set_led(tt);
85 }
86 
87 /*
88  * The urb cannot be reused until the urb completes
89  */
90 static void ttusbir_bulk_complete(struct urb *urb)
91 {
92 	struct ttusbir *tt = urb->context;
93 
94 	atomic_dec(&tt->led_complete);
95 
96 	switch (urb->status) {
97 	case 0:
98 		break;
99 	case -ECONNRESET:
100 	case -ENOENT:
101 	case -ESHUTDOWN:
102 		usb_unlink_urb(urb);
103 		return;
104 	case -EPIPE:
105 	default:
106 		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
107 		break;
108 	}
109 
110 	ttusbir_set_led(tt);
111 }
112 
113 /*
114  * The data is one bit per sample, a set bit signifying silence and samples
115  * being MSB first. Bit 0 can contain garbage so take it to be whatever
116  * bit 1 is, so we don't have unexpected edges.
117  */
118 static void ttusbir_process_ir_data(struct ttusbir *tt, uint8_t *buf)
119 {
120 	struct ir_raw_event rawir;
121 	unsigned i, v, b;
122 	bool event = false;
123 
124 	init_ir_raw_event(&rawir);
125 
126 	for (i = 0; i < 128; i++) {
127 		v = buf[i] & 0xfe;
128 		switch (v) {
129 		case 0xfe:
130 			rawir.pulse = false;
131 			rawir.duration = NS_PER_BYTE;
132 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
133 				event = true;
134 			break;
135 		case 0:
136 			rawir.pulse = true;
137 			rawir.duration = NS_PER_BYTE;
138 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
139 				event = true;
140 			break;
141 		default:
142 			/* one edge per byte */
143 			if (v & 2) {
144 				b = ffz(v | 1);
145 				rawir.pulse = true;
146 			} else {
147 				b = ffs(v) - 1;
148 				rawir.pulse = false;
149 			}
150 
151 			rawir.duration = NS_PER_BIT * (8 - b);
152 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
153 				event = true;
154 
155 			rawir.pulse = !rawir.pulse;
156 			rawir.duration = NS_PER_BIT * b;
157 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
158 				event = true;
159 			break;
160 		}
161 	}
162 
163 	/* don't wakeup when there's nothing to do */
164 	if (event)
165 		ir_raw_event_handle(tt->rc);
166 }
167 
168 static void ttusbir_urb_complete(struct urb *urb)
169 {
170 	struct ttusbir *tt = urb->context;
171 	int rc;
172 
173 	switch (urb->status) {
174 	case 0:
175 		ttusbir_process_ir_data(tt, urb->transfer_buffer);
176 		break;
177 	case -ECONNRESET:
178 	case -ENOENT:
179 	case -ESHUTDOWN:
180 		usb_unlink_urb(urb);
181 		return;
182 	case -EPIPE:
183 	default:
184 		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
185 		break;
186 	}
187 
188 	rc = usb_submit_urb(urb, GFP_ATOMIC);
189 	if (rc && rc != -ENODEV)
190 		dev_warn(tt->dev, "failed to resubmit urb: %d\n", rc);
191 }
192 
193 static int ttusbir_probe(struct usb_interface *intf,
194 			 const struct usb_device_id *id)
195 {
196 	struct ttusbir *tt;
197 	struct usb_interface_descriptor *idesc;
198 	struct usb_endpoint_descriptor *desc;
199 	struct rc_dev *rc;
200 	int i, j, ret;
201 	int altsetting = -1;
202 
203 	tt = kzalloc(sizeof(*tt), GFP_KERNEL);
204 	rc = rc_allocate_device(RC_DRIVER_IR_RAW);
205 	if (!tt || !rc) {
206 		ret = -ENOMEM;
207 		goto out;
208 	}
209 
210 	/* find the correct alt setting */
211 	for (i = 0; i < intf->num_altsetting && altsetting == -1; i++) {
212 		int max_packet, bulk_out_endp = -1, iso_in_endp = -1;
213 
214 		idesc = &intf->altsetting[i].desc;
215 
216 		for (j = 0; j < idesc->bNumEndpoints; j++) {
217 			desc = &intf->altsetting[i].endpoint[j].desc;
218 			max_packet = le16_to_cpu(desc->wMaxPacketSize);
219 			if (usb_endpoint_dir_in(desc) &&
220 					usb_endpoint_xfer_isoc(desc) &&
221 					max_packet == 0x10)
222 				iso_in_endp = j;
223 			else if (usb_endpoint_dir_out(desc) &&
224 					usb_endpoint_xfer_bulk(desc) &&
225 					max_packet == 0x20)
226 				bulk_out_endp = j;
227 
228 			if (bulk_out_endp != -1 && iso_in_endp != -1) {
229 				tt->bulk_out_endp = bulk_out_endp;
230 				tt->iso_in_endp = iso_in_endp;
231 				altsetting = i;
232 				break;
233 			}
234 		}
235 	}
236 
237 	if (altsetting == -1) {
238 		dev_err(&intf->dev, "cannot find expected altsetting\n");
239 		ret = -ENODEV;
240 		goto out;
241 	}
242 
243 	tt->dev = &intf->dev;
244 	tt->udev = interface_to_usbdev(intf);
245 	tt->rc = rc;
246 
247 	ret = usb_set_interface(tt->udev, 0, altsetting);
248 	if (ret)
249 		goto out;
250 
251 	for (i = 0; i < NUM_URBS; i++) {
252 		struct urb *urb = usb_alloc_urb(8, GFP_KERNEL);
253 		void *buffer;
254 
255 		if (!urb) {
256 			ret = -ENOMEM;
257 			goto out;
258 		}
259 
260 		urb->dev = tt->udev;
261 		urb->context = tt;
262 		urb->pipe = usb_rcvisocpipe(tt->udev, tt->iso_in_endp);
263 		urb->interval = 1;
264 		buffer = usb_alloc_coherent(tt->udev, 128, GFP_KERNEL,
265 						&urb->transfer_dma);
266 		if (!buffer) {
267 			usb_free_urb(urb);
268 			ret = -ENOMEM;
269 			goto out;
270 		}
271 		urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP | URB_ISO_ASAP;
272 		urb->transfer_buffer = buffer;
273 		urb->complete = ttusbir_urb_complete;
274 		urb->number_of_packets = 8;
275 		urb->transfer_buffer_length = 128;
276 
277 		for (j = 0; j < 8; j++) {
278 			urb->iso_frame_desc[j].offset = j * 16;
279 			urb->iso_frame_desc[j].length = 16;
280 		}
281 
282 		tt->urb[i] = urb;
283 	}
284 
285 	tt->bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
286 	if (!tt->bulk_urb) {
287 		ret = -ENOMEM;
288 		goto out;
289 	}
290 
291 	tt->bulk_buffer[0] = 0xaa;
292 	tt->bulk_buffer[1] = 0x01;
293 	tt->bulk_buffer[2] = 0x05;
294 	tt->bulk_buffer[3] = 0x01;
295 
296 	usb_fill_bulk_urb(tt->bulk_urb, tt->udev, usb_sndbulkpipe(tt->udev,
297 		tt->bulk_out_endp), tt->bulk_buffer, sizeof(tt->bulk_buffer),
298 						ttusbir_bulk_complete, tt);
299 
300 	tt->led.name = "ttusbir:green:power";
301 	tt->led.default_trigger = "rc-feedback";
302 	tt->led.brightness_set = ttusbir_brightness_set;
303 	tt->led.brightness_get = ttusbir_brightness_get;
304 	tt->is_led_on = tt->led_on = true;
305 	atomic_set(&tt->led_complete, 0);
306 	ret = led_classdev_register(&intf->dev, &tt->led);
307 	if (ret)
308 		goto out;
309 
310 	usb_make_path(tt->udev, tt->phys, sizeof(tt->phys));
311 
312 	rc->input_name = DRIVER_DESC;
313 	rc->input_phys = tt->phys;
314 	usb_to_input_id(tt->udev, &rc->input_id);
315 	rc->dev.parent = &intf->dev;
316 	rc->allowed_protocols = RC_BIT_ALL_IR_DECODER;
317 	rc->priv = tt;
318 	rc->driver_name = DRIVER_NAME;
319 	rc->map_name = RC_MAP_TT_1500;
320 	rc->min_timeout = 1;
321 	rc->timeout = IR_DEFAULT_TIMEOUT;
322 	rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
323 
324 	/*
325 	 * The precision is NS_PER_BIT, but since every 8th bit can be
326 	 * overwritten with garbage the accuracy is at best 2 * NS_PER_BIT.
327 	 */
328 	rc->rx_resolution = NS_PER_BIT;
329 
330 	ret = rc_register_device(rc);
331 	if (ret) {
332 		dev_err(&intf->dev, "failed to register rc device %d\n", ret);
333 		goto out2;
334 	}
335 
336 	usb_set_intfdata(intf, tt);
337 
338 	for (i = 0; i < NUM_URBS; i++) {
339 		ret = usb_submit_urb(tt->urb[i], GFP_KERNEL);
340 		if (ret) {
341 			dev_err(tt->dev, "failed to submit urb %d\n", ret);
342 			goto out3;
343 		}
344 	}
345 
346 	return 0;
347 out3:
348 	rc_unregister_device(rc);
349 	rc = NULL;
350 out2:
351 	led_classdev_unregister(&tt->led);
352 out:
353 	if (tt) {
354 		for (i = 0; i < NUM_URBS && tt->urb[i]; i++) {
355 			struct urb *urb = tt->urb[i];
356 
357 			usb_kill_urb(urb);
358 			usb_free_coherent(tt->udev, 128, urb->transfer_buffer,
359 							urb->transfer_dma);
360 			usb_free_urb(urb);
361 		}
362 		usb_kill_urb(tt->bulk_urb);
363 		usb_free_urb(tt->bulk_urb);
364 		kfree(tt);
365 	}
366 	rc_free_device(rc);
367 
368 	return ret;
369 }
370 
371 static void ttusbir_disconnect(struct usb_interface *intf)
372 {
373 	struct ttusbir *tt = usb_get_intfdata(intf);
374 	struct usb_device *udev = tt->udev;
375 	int i;
376 
377 	tt->udev = NULL;
378 
379 	rc_unregister_device(tt->rc);
380 	led_classdev_unregister(&tt->led);
381 	for (i = 0; i < NUM_URBS; i++) {
382 		usb_kill_urb(tt->urb[i]);
383 		usb_free_coherent(udev, 128, tt->urb[i]->transfer_buffer,
384 						tt->urb[i]->transfer_dma);
385 		usb_free_urb(tt->urb[i]);
386 	}
387 	usb_kill_urb(tt->bulk_urb);
388 	usb_free_urb(tt->bulk_urb);
389 	usb_set_intfdata(intf, NULL);
390 	kfree(tt);
391 }
392 
393 static int ttusbir_suspend(struct usb_interface *intf, pm_message_t message)
394 {
395 	struct ttusbir *tt = usb_get_intfdata(intf);
396 	int i;
397 
398 	for (i = 0; i < NUM_URBS; i++)
399 		usb_kill_urb(tt->urb[i]);
400 
401 	led_classdev_suspend(&tt->led);
402 	usb_kill_urb(tt->bulk_urb);
403 
404 	return 0;
405 }
406 
407 static int ttusbir_resume(struct usb_interface *intf)
408 {
409 	struct ttusbir *tt = usb_get_intfdata(intf);
410 	int i, rc;
411 
412 	tt->is_led_on = true;
413 	led_classdev_resume(&tt->led);
414 
415 	for (i = 0; i < NUM_URBS; i++) {
416 		rc = usb_submit_urb(tt->urb[i], GFP_KERNEL);
417 		if (rc) {
418 			dev_warn(tt->dev, "failed to submit urb: %d\n", rc);
419 			break;
420 		}
421 	}
422 
423 	return rc;
424 }
425 
426 static const struct usb_device_id ttusbir_table[] = {
427 	{ USB_DEVICE(0x0b48, 0x2003) },
428 	{ }
429 };
430 
431 static struct usb_driver ttusbir_driver = {
432 	.name = DRIVER_NAME,
433 	.id_table = ttusbir_table,
434 	.probe = ttusbir_probe,
435 	.suspend = ttusbir_suspend,
436 	.resume = ttusbir_resume,
437 	.reset_resume = ttusbir_resume,
438 	.disconnect = ttusbir_disconnect,
439 };
440 
441 module_usb_driver(ttusbir_driver);
442 
443 MODULE_DESCRIPTION(DRIVER_DESC);
444 MODULE_AUTHOR("Sean Young <sean@mess.org>");
445 MODULE_LICENSE("GPL");
446 MODULE_DEVICE_TABLE(usb, ttusbir_table);
447 
448