xref: /openbmc/linux/drivers/media/rc/ttusbir.c (revision 9a29f5fc)
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 US_PER_BYTE	62
24 #define US_PER_BIT	(US_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 		return;
94 	case -EPIPE:
95 	default:
96 		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
97 		break;
98 	}
99 
100 	ttusbir_set_led(tt);
101 }
102 
103 /*
104  * The data is one bit per sample, a set bit signifying silence and samples
105  * being MSB first. Bit 0 can contain garbage so take it to be whatever
106  * bit 1 is, so we don't have unexpected edges.
107  */
108 static void ttusbir_process_ir_data(struct ttusbir *tt, uint8_t *buf)
109 {
110 	struct ir_raw_event rawir = {};
111 	unsigned i, v, b;
112 	bool event = false;
113 
114 	for (i = 0; i < 128; i++) {
115 		v = buf[i] & 0xfe;
116 		switch (v) {
117 		case 0xfe:
118 			rawir.pulse = false;
119 			rawir.duration = US_PER_BYTE;
120 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
121 				event = true;
122 			break;
123 		case 0:
124 			rawir.pulse = true;
125 			rawir.duration = US_PER_BYTE;
126 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
127 				event = true;
128 			break;
129 		default:
130 			/* one edge per byte */
131 			if (v & 2) {
132 				b = ffz(v | 1);
133 				rawir.pulse = true;
134 			} else {
135 				b = ffs(v) - 1;
136 				rawir.pulse = false;
137 			}
138 
139 			rawir.duration = US_PER_BIT * (8 - b);
140 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
141 				event = true;
142 
143 			rawir.pulse = !rawir.pulse;
144 			rawir.duration = US_PER_BIT * b;
145 			if (ir_raw_event_store_with_filter(tt->rc, &rawir))
146 				event = true;
147 			break;
148 		}
149 	}
150 
151 	/* don't wakeup when there's nothing to do */
152 	if (event)
153 		ir_raw_event_handle(tt->rc);
154 }
155 
156 static void ttusbir_urb_complete(struct urb *urb)
157 {
158 	struct ttusbir *tt = urb->context;
159 	int rc;
160 
161 	switch (urb->status) {
162 	case 0:
163 		ttusbir_process_ir_data(tt, urb->transfer_buffer);
164 		break;
165 	case -ECONNRESET:
166 	case -ENOENT:
167 	case -ESHUTDOWN:
168 		return;
169 	case -EPIPE:
170 	default:
171 		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
172 		break;
173 	}
174 
175 	rc = usb_submit_urb(urb, GFP_ATOMIC);
176 	if (rc && rc != -ENODEV)
177 		dev_warn(tt->dev, "failed to resubmit urb: %d\n", rc);
178 }
179 
180 static int ttusbir_probe(struct usb_interface *intf,
181 			 const struct usb_device_id *id)
182 {
183 	struct ttusbir *tt;
184 	struct usb_interface_descriptor *idesc;
185 	struct usb_endpoint_descriptor *desc;
186 	struct rc_dev *rc;
187 	int i, j, ret;
188 	int altsetting = -1;
189 
190 	tt = kzalloc(sizeof(*tt), GFP_KERNEL);
191 	rc = rc_allocate_device(RC_DRIVER_IR_RAW);
192 	if (!tt || !rc) {
193 		ret = -ENOMEM;
194 		goto out;
195 	}
196 
197 	/* find the correct alt setting */
198 	for (i = 0; i < intf->num_altsetting && altsetting == -1; i++) {
199 		int max_packet, bulk_out_endp = -1, iso_in_endp = -1;
200 
201 		idesc = &intf->altsetting[i].desc;
202 
203 		for (j = 0; j < idesc->bNumEndpoints; j++) {
204 			desc = &intf->altsetting[i].endpoint[j].desc;
205 			max_packet = le16_to_cpu(desc->wMaxPacketSize);
206 			if (usb_endpoint_dir_in(desc) &&
207 					usb_endpoint_xfer_isoc(desc) &&
208 					max_packet == 0x10)
209 				iso_in_endp = j;
210 			else if (usb_endpoint_dir_out(desc) &&
211 					usb_endpoint_xfer_bulk(desc) &&
212 					max_packet == 0x20)
213 				bulk_out_endp = j;
214 
215 			if (bulk_out_endp != -1 && iso_in_endp != -1) {
216 				tt->bulk_out_endp = bulk_out_endp;
217 				tt->iso_in_endp = iso_in_endp;
218 				altsetting = i;
219 				break;
220 			}
221 		}
222 	}
223 
224 	if (altsetting == -1) {
225 		dev_err(&intf->dev, "cannot find expected altsetting\n");
226 		ret = -ENODEV;
227 		goto out;
228 	}
229 
230 	tt->dev = &intf->dev;
231 	tt->udev = interface_to_usbdev(intf);
232 	tt->rc = rc;
233 
234 	ret = usb_set_interface(tt->udev, 0, altsetting);
235 	if (ret)
236 		goto out;
237 
238 	for (i = 0; i < NUM_URBS; i++) {
239 		struct urb *urb = usb_alloc_urb(8, GFP_KERNEL);
240 		void *buffer;
241 
242 		if (!urb) {
243 			ret = -ENOMEM;
244 			goto out;
245 		}
246 
247 		urb->dev = tt->udev;
248 		urb->context = tt;
249 		urb->pipe = usb_rcvisocpipe(tt->udev, tt->iso_in_endp);
250 		urb->interval = 1;
251 		buffer = usb_alloc_coherent(tt->udev, 128, GFP_KERNEL,
252 						&urb->transfer_dma);
253 		if (!buffer) {
254 			usb_free_urb(urb);
255 			ret = -ENOMEM;
256 			goto out;
257 		}
258 		urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP | URB_ISO_ASAP;
259 		urb->transfer_buffer = buffer;
260 		urb->complete = ttusbir_urb_complete;
261 		urb->number_of_packets = 8;
262 		urb->transfer_buffer_length = 128;
263 
264 		for (j = 0; j < 8; j++) {
265 			urb->iso_frame_desc[j].offset = j * 16;
266 			urb->iso_frame_desc[j].length = 16;
267 		}
268 
269 		tt->urb[i] = urb;
270 	}
271 
272 	tt->bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
273 	if (!tt->bulk_urb) {
274 		ret = -ENOMEM;
275 		goto out;
276 	}
277 
278 	tt->bulk_buffer[0] = 0xaa;
279 	tt->bulk_buffer[1] = 0x01;
280 	tt->bulk_buffer[2] = 0x05;
281 	tt->bulk_buffer[3] = 0x01;
282 
283 	usb_fill_bulk_urb(tt->bulk_urb, tt->udev, usb_sndbulkpipe(tt->udev,
284 		tt->bulk_out_endp), tt->bulk_buffer, sizeof(tt->bulk_buffer),
285 						ttusbir_bulk_complete, tt);
286 
287 	tt->led.name = "ttusbir:green:power";
288 	tt->led.default_trigger = "rc-feedback";
289 	tt->led.brightness_set = ttusbir_brightness_set;
290 	tt->led.brightness_get = ttusbir_brightness_get;
291 	tt->is_led_on = tt->led_on = true;
292 	atomic_set(&tt->led_complete, 0);
293 	ret = led_classdev_register(&intf->dev, &tt->led);
294 	if (ret)
295 		goto out;
296 
297 	usb_make_path(tt->udev, tt->phys, sizeof(tt->phys));
298 
299 	rc->device_name = DRIVER_DESC;
300 	rc->input_phys = tt->phys;
301 	usb_to_input_id(tt->udev, &rc->input_id);
302 	rc->dev.parent = &intf->dev;
303 	rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
304 	rc->priv = tt;
305 	rc->driver_name = DRIVER_NAME;
306 	rc->map_name = RC_MAP_TT_1500;
307 	rc->min_timeout = 1;
308 	rc->timeout = IR_DEFAULT_TIMEOUT;
309 	rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
310 
311 	/*
312 	 * The precision is US_PER_BIT, but since every 8th bit can be
313 	 * overwritten with garbage the accuracy is at best 2 * US_PER_BIT.
314 	 */
315 	rc->rx_resolution = 2 * US_PER_BIT;
316 
317 	ret = rc_register_device(rc);
318 	if (ret) {
319 		dev_err(&intf->dev, "failed to register rc device %d\n", ret);
320 		goto out2;
321 	}
322 
323 	usb_set_intfdata(intf, tt);
324 
325 	for (i = 0; i < NUM_URBS; i++) {
326 		ret = usb_submit_urb(tt->urb[i], GFP_KERNEL);
327 		if (ret) {
328 			dev_err(tt->dev, "failed to submit urb %d\n", ret);
329 			goto out3;
330 		}
331 	}
332 
333 	return 0;
334 out3:
335 	rc_unregister_device(rc);
336 	rc = NULL;
337 out2:
338 	led_classdev_unregister(&tt->led);
339 out:
340 	if (tt) {
341 		for (i = 0; i < NUM_URBS && tt->urb[i]; i++) {
342 			struct urb *urb = tt->urb[i];
343 
344 			usb_kill_urb(urb);
345 			usb_free_coherent(tt->udev, 128, urb->transfer_buffer,
346 							urb->transfer_dma);
347 			usb_free_urb(urb);
348 		}
349 		usb_kill_urb(tt->bulk_urb);
350 		usb_free_urb(tt->bulk_urb);
351 		kfree(tt);
352 	}
353 	rc_free_device(rc);
354 
355 	return ret;
356 }
357 
358 static void ttusbir_disconnect(struct usb_interface *intf)
359 {
360 	struct ttusbir *tt = usb_get_intfdata(intf);
361 	struct usb_device *udev = tt->udev;
362 	int i;
363 
364 	tt->udev = NULL;
365 
366 	rc_unregister_device(tt->rc);
367 	led_classdev_unregister(&tt->led);
368 	for (i = 0; i < NUM_URBS; i++) {
369 		usb_kill_urb(tt->urb[i]);
370 		usb_free_coherent(udev, 128, tt->urb[i]->transfer_buffer,
371 						tt->urb[i]->transfer_dma);
372 		usb_free_urb(tt->urb[i]);
373 	}
374 	usb_kill_urb(tt->bulk_urb);
375 	usb_free_urb(tt->bulk_urb);
376 	usb_set_intfdata(intf, NULL);
377 	kfree(tt);
378 }
379 
380 static int ttusbir_suspend(struct usb_interface *intf, pm_message_t message)
381 {
382 	struct ttusbir *tt = usb_get_intfdata(intf);
383 	int i;
384 
385 	for (i = 0; i < NUM_URBS; i++)
386 		usb_kill_urb(tt->urb[i]);
387 
388 	led_classdev_suspend(&tt->led);
389 	usb_kill_urb(tt->bulk_urb);
390 
391 	return 0;
392 }
393 
394 static int ttusbir_resume(struct usb_interface *intf)
395 {
396 	struct ttusbir *tt = usb_get_intfdata(intf);
397 	int i, rc;
398 
399 	tt->is_led_on = true;
400 	led_classdev_resume(&tt->led);
401 
402 	for (i = 0; i < NUM_URBS; i++) {
403 		rc = usb_submit_urb(tt->urb[i], GFP_NOIO);
404 		if (rc) {
405 			dev_warn(tt->dev, "failed to submit urb: %d\n", rc);
406 			break;
407 		}
408 	}
409 
410 	return rc;
411 }
412 
413 static const struct usb_device_id ttusbir_table[] = {
414 	{ USB_DEVICE(0x0b48, 0x2003) },
415 	{ }
416 };
417 
418 static struct usb_driver ttusbir_driver = {
419 	.name = DRIVER_NAME,
420 	.id_table = ttusbir_table,
421 	.probe = ttusbir_probe,
422 	.suspend = ttusbir_suspend,
423 	.resume = ttusbir_resume,
424 	.reset_resume = ttusbir_resume,
425 	.disconnect = ttusbir_disconnect,
426 };
427 
428 module_usb_driver(ttusbir_driver);
429 
430 MODULE_DESCRIPTION(DRIVER_DESC);
431 MODULE_AUTHOR("Sean Young <sean@mess.org>");
432 MODULE_LICENSE("GPL");
433 MODULE_DEVICE_TABLE(usb, ttusbir_table);
434 
435