xref: /openbmc/linux/drivers/media/rc/ttusbir.c (revision 9123e3a7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * TechnoTrend USB IR Receiver
4  *
5  * Copyright (C) 2012 Sean Young <sean@mess.org>
6  */
7 
8 #include <linux/module.h>
9 #include <linux/usb.h>
10 #include <linux/usb/input.h>
11 #include <linux/slab.h>
12 #include <linux/leds.h>
13 #include <media/rc-core.h>
14 
15 #define DRIVER_NAME	"ttusbir"
16 #define DRIVER_DESC	"TechnoTrend USB IR Receiver"
17 /*
18  * The Windows driver uses 8 URBS, the original lirc drivers has a
19  * configurable amount (2 default, 4 max). This device generates about 125
20  * messages per second (!), whether IR is idle or not.
21  */
22 #define NUM_URBS	4
23 #define NS_PER_BYTE	62500
24 #define NS_PER_BIT	(NS_PER_BYTE/8)
25 
26 struct ttusbir {
27 	struct rc_dev *rc;
28 	struct device *dev;
29 	struct usb_device *udev;
30 
31 	struct urb *urb[NUM_URBS];
32 
33 	struct led_classdev led;
34 	struct urb *bulk_urb;
35 	uint8_t bulk_buffer[5];
36 	int bulk_out_endp, iso_in_endp;
37 	bool led_on, is_led_on;
38 	atomic_t led_complete;
39 
40 	char phys[64];
41 };
42 
43 static enum led_brightness ttusbir_brightness_get(struct led_classdev *led_dev)
44 {
45 	struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
46 
47 	return tt->led_on ? LED_FULL : LED_OFF;
48 }
49 
50 static void ttusbir_set_led(struct ttusbir *tt)
51 {
52 	int ret;
53 
54 	smp_mb();
55 
56 	if (tt->led_on != tt->is_led_on && tt->udev &&
57 				atomic_add_unless(&tt->led_complete, 1, 1)) {
58 		tt->bulk_buffer[4] = tt->is_led_on = tt->led_on;
59 		ret = usb_submit_urb(tt->bulk_urb, GFP_ATOMIC);
60 		if (ret) {
61 			dev_warn(tt->dev, "failed to submit bulk urb: %d\n",
62 									ret);
63 			atomic_dec(&tt->led_complete);
64 		}
65 	}
66 }
67 
68 static void ttusbir_brightness_set(struct led_classdev *led_dev, enum
69 						led_brightness brightness)
70 {
71 	struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
72 
73 	tt->led_on = brightness != LED_OFF;
74 
75 	ttusbir_set_led(tt);
76 }
77 
78 /*
79  * The urb cannot be reused until the urb completes
80  */
81 static void ttusbir_bulk_complete(struct urb *urb)
82 {
83 	struct ttusbir *tt = urb->context;
84 
85 	atomic_dec(&tt->led_complete);
86 
87 	switch (urb->status) {
88 	case 0:
89 		break;
90 	case -ECONNRESET:
91 	case -ENOENT:
92 	case -ESHUTDOWN:
93 		usb_unlink_urb(urb);
94 		return;
95 	case -EPIPE:
96 	default:
97 		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
98 		break;
99 	}
100 
101 	ttusbir_set_led(tt);
102 }
103 
104 /*
105  * The data is one bit per sample, a set bit signifying silence and samples
106  * being MSB first. Bit 0 can contain garbage so take it to be whatever
107  * bit 1 is, so we don't have unexpected edges.
108  */
109 static void ttusbir_process_ir_data(struct ttusbir *tt, uint8_t *buf)
110 {
111 	struct ir_raw_event rawir = {};
112 	unsigned i, v, b;
113 	bool event = false;
114 
115 	for (i = 0; i < 128; i++) {
116 		v = buf[i] & 0xfe;
117 		switch (v) {
118 		case 0xfe:
119 			rawir.pulse = false;
120 			rawir.duration = NS_PER_BYTE;
121 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
122 				event = true;
123 			break;
124 		case 0:
125 			rawir.pulse = true;
126 			rawir.duration = NS_PER_BYTE;
127 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
128 				event = true;
129 			break;
130 		default:
131 			/* one edge per byte */
132 			if (v & 2) {
133 				b = ffz(v | 1);
134 				rawir.pulse = true;
135 			} else {
136 				b = ffs(v) - 1;
137 				rawir.pulse = false;
138 			}
139 
140 			rawir.duration = NS_PER_BIT * (8 - b);
141 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
142 				event = true;
143 
144 			rawir.pulse = !rawir.pulse;
145 			rawir.duration = NS_PER_BIT * b;
146 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
147 				event = true;
148 			break;
149 		}
150 	}
151 
152 	/* don't wakeup when there's nothing to do */
153 	if (event)
154 		ir_raw_event_handle(tt->rc);
155 }
156 
157 static void ttusbir_urb_complete(struct urb *urb)
158 {
159 	struct ttusbir *tt = urb->context;
160 	int rc;
161 
162 	switch (urb->status) {
163 	case 0:
164 		ttusbir_process_ir_data(tt, urb->transfer_buffer);
165 		break;
166 	case -ECONNRESET:
167 	case -ENOENT:
168 	case -ESHUTDOWN:
169 		usb_unlink_urb(urb);
170 		return;
171 	case -EPIPE:
172 	default:
173 		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
174 		break;
175 	}
176 
177 	rc = usb_submit_urb(urb, GFP_ATOMIC);
178 	if (rc && rc != -ENODEV)
179 		dev_warn(tt->dev, "failed to resubmit urb: %d\n", rc);
180 }
181 
182 static int ttusbir_probe(struct usb_interface *intf,
183 			 const struct usb_device_id *id)
184 {
185 	struct ttusbir *tt;
186 	struct usb_interface_descriptor *idesc;
187 	struct usb_endpoint_descriptor *desc;
188 	struct rc_dev *rc;
189 	int i, j, ret;
190 	int altsetting = -1;
191 
192 	tt = kzalloc(sizeof(*tt), GFP_KERNEL);
193 	rc = rc_allocate_device(RC_DRIVER_IR_RAW);
194 	if (!tt || !rc) {
195 		ret = -ENOMEM;
196 		goto out;
197 	}
198 
199 	/* find the correct alt setting */
200 	for (i = 0; i < intf->num_altsetting && altsetting == -1; i++) {
201 		int max_packet, bulk_out_endp = -1, iso_in_endp = -1;
202 
203 		idesc = &intf->altsetting[i].desc;
204 
205 		for (j = 0; j < idesc->bNumEndpoints; j++) {
206 			desc = &intf->altsetting[i].endpoint[j].desc;
207 			max_packet = le16_to_cpu(desc->wMaxPacketSize);
208 			if (usb_endpoint_dir_in(desc) &&
209 					usb_endpoint_xfer_isoc(desc) &&
210 					max_packet == 0x10)
211 				iso_in_endp = j;
212 			else if (usb_endpoint_dir_out(desc) &&
213 					usb_endpoint_xfer_bulk(desc) &&
214 					max_packet == 0x20)
215 				bulk_out_endp = j;
216 
217 			if (bulk_out_endp != -1 && iso_in_endp != -1) {
218 				tt->bulk_out_endp = bulk_out_endp;
219 				tt->iso_in_endp = iso_in_endp;
220 				altsetting = i;
221 				break;
222 			}
223 		}
224 	}
225 
226 	if (altsetting == -1) {
227 		dev_err(&intf->dev, "cannot find expected altsetting\n");
228 		ret = -ENODEV;
229 		goto out;
230 	}
231 
232 	tt->dev = &intf->dev;
233 	tt->udev = interface_to_usbdev(intf);
234 	tt->rc = rc;
235 
236 	ret = usb_set_interface(tt->udev, 0, altsetting);
237 	if (ret)
238 		goto out;
239 
240 	for (i = 0; i < NUM_URBS; i++) {
241 		struct urb *urb = usb_alloc_urb(8, GFP_KERNEL);
242 		void *buffer;
243 
244 		if (!urb) {
245 			ret = -ENOMEM;
246 			goto out;
247 		}
248 
249 		urb->dev = tt->udev;
250 		urb->context = tt;
251 		urb->pipe = usb_rcvisocpipe(tt->udev, tt->iso_in_endp);
252 		urb->interval = 1;
253 		buffer = usb_alloc_coherent(tt->udev, 128, GFP_KERNEL,
254 						&urb->transfer_dma);
255 		if (!buffer) {
256 			usb_free_urb(urb);
257 			ret = -ENOMEM;
258 			goto out;
259 		}
260 		urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP | URB_ISO_ASAP;
261 		urb->transfer_buffer = buffer;
262 		urb->complete = ttusbir_urb_complete;
263 		urb->number_of_packets = 8;
264 		urb->transfer_buffer_length = 128;
265 
266 		for (j = 0; j < 8; j++) {
267 			urb->iso_frame_desc[j].offset = j * 16;
268 			urb->iso_frame_desc[j].length = 16;
269 		}
270 
271 		tt->urb[i] = urb;
272 	}
273 
274 	tt->bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
275 	if (!tt->bulk_urb) {
276 		ret = -ENOMEM;
277 		goto out;
278 	}
279 
280 	tt->bulk_buffer[0] = 0xaa;
281 	tt->bulk_buffer[1] = 0x01;
282 	tt->bulk_buffer[2] = 0x05;
283 	tt->bulk_buffer[3] = 0x01;
284 
285 	usb_fill_bulk_urb(tt->bulk_urb, tt->udev, usb_sndbulkpipe(tt->udev,
286 		tt->bulk_out_endp), tt->bulk_buffer, sizeof(tt->bulk_buffer),
287 						ttusbir_bulk_complete, tt);
288 
289 	tt->led.name = "ttusbir:green:power";
290 	tt->led.default_trigger = "rc-feedback";
291 	tt->led.brightness_set = ttusbir_brightness_set;
292 	tt->led.brightness_get = ttusbir_brightness_get;
293 	tt->is_led_on = tt->led_on = true;
294 	atomic_set(&tt->led_complete, 0);
295 	ret = led_classdev_register(&intf->dev, &tt->led);
296 	if (ret)
297 		goto out;
298 
299 	usb_make_path(tt->udev, tt->phys, sizeof(tt->phys));
300 
301 	rc->device_name = DRIVER_DESC;
302 	rc->input_phys = tt->phys;
303 	usb_to_input_id(tt->udev, &rc->input_id);
304 	rc->dev.parent = &intf->dev;
305 	rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
306 	rc->priv = tt;
307 	rc->driver_name = DRIVER_NAME;
308 	rc->map_name = RC_MAP_TT_1500;
309 	rc->min_timeout = 1;
310 	rc->timeout = IR_DEFAULT_TIMEOUT;
311 	rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
312 
313 	/*
314 	 * The precision is NS_PER_BIT, but since every 8th bit can be
315 	 * overwritten with garbage the accuracy is at best 2 * NS_PER_BIT.
316 	 */
317 	rc->rx_resolution = NS_PER_BIT;
318 
319 	ret = rc_register_device(rc);
320 	if (ret) {
321 		dev_err(&intf->dev, "failed to register rc device %d\n", ret);
322 		goto out2;
323 	}
324 
325 	usb_set_intfdata(intf, tt);
326 
327 	for (i = 0; i < NUM_URBS; i++) {
328 		ret = usb_submit_urb(tt->urb[i], GFP_KERNEL);
329 		if (ret) {
330 			dev_err(tt->dev, "failed to submit urb %d\n", ret);
331 			goto out3;
332 		}
333 	}
334 
335 	return 0;
336 out3:
337 	rc_unregister_device(rc);
338 	rc = NULL;
339 out2:
340 	led_classdev_unregister(&tt->led);
341 out:
342 	if (tt) {
343 		for (i = 0; i < NUM_URBS && tt->urb[i]; i++) {
344 			struct urb *urb = tt->urb[i];
345 
346 			usb_kill_urb(urb);
347 			usb_free_coherent(tt->udev, 128, urb->transfer_buffer,
348 							urb->transfer_dma);
349 			usb_free_urb(urb);
350 		}
351 		usb_kill_urb(tt->bulk_urb);
352 		usb_free_urb(tt->bulk_urb);
353 		kfree(tt);
354 	}
355 	rc_free_device(rc);
356 
357 	return ret;
358 }
359 
360 static void ttusbir_disconnect(struct usb_interface *intf)
361 {
362 	struct ttusbir *tt = usb_get_intfdata(intf);
363 	struct usb_device *udev = tt->udev;
364 	int i;
365 
366 	tt->udev = NULL;
367 
368 	rc_unregister_device(tt->rc);
369 	led_classdev_unregister(&tt->led);
370 	for (i = 0; i < NUM_URBS; i++) {
371 		usb_kill_urb(tt->urb[i]);
372 		usb_free_coherent(udev, 128, tt->urb[i]->transfer_buffer,
373 						tt->urb[i]->transfer_dma);
374 		usb_free_urb(tt->urb[i]);
375 	}
376 	usb_kill_urb(tt->bulk_urb);
377 	usb_free_urb(tt->bulk_urb);
378 	usb_set_intfdata(intf, NULL);
379 	kfree(tt);
380 }
381 
382 static int ttusbir_suspend(struct usb_interface *intf, pm_message_t message)
383 {
384 	struct ttusbir *tt = usb_get_intfdata(intf);
385 	int i;
386 
387 	for (i = 0; i < NUM_URBS; i++)
388 		usb_kill_urb(tt->urb[i]);
389 
390 	led_classdev_suspend(&tt->led);
391 	usb_kill_urb(tt->bulk_urb);
392 
393 	return 0;
394 }
395 
396 static int ttusbir_resume(struct usb_interface *intf)
397 {
398 	struct ttusbir *tt = usb_get_intfdata(intf);
399 	int i, rc;
400 
401 	tt->is_led_on = true;
402 	led_classdev_resume(&tt->led);
403 
404 	for (i = 0; i < NUM_URBS; i++) {
405 		rc = usb_submit_urb(tt->urb[i], GFP_KERNEL);
406 		if (rc) {
407 			dev_warn(tt->dev, "failed to submit urb: %d\n", rc);
408 			break;
409 		}
410 	}
411 
412 	return rc;
413 }
414 
415 static const struct usb_device_id ttusbir_table[] = {
416 	{ USB_DEVICE(0x0b48, 0x2003) },
417 	{ }
418 };
419 
420 static struct usb_driver ttusbir_driver = {
421 	.name = DRIVER_NAME,
422 	.id_table = ttusbir_table,
423 	.probe = ttusbir_probe,
424 	.suspend = ttusbir_suspend,
425 	.resume = ttusbir_resume,
426 	.reset_resume = ttusbir_resume,
427 	.disconnect = ttusbir_disconnect,
428 };
429 
430 module_usb_driver(ttusbir_driver);
431 
432 MODULE_DESCRIPTION(DRIVER_DESC);
433 MODULE_AUTHOR("Sean Young <sean@mess.org>");
434 MODULE_LICENSE("GPL");
435 MODULE_DEVICE_TABLE(usb, ttusbir_table);
436 
437