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
ttusbir_brightness_get(struct led_classdev * led_dev)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
ttusbir_set_led(struct ttusbir * tt)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
ttusbir_brightness_set(struct led_classdev * led_dev,enum led_brightness brightness)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 */
ttusbir_bulk_complete(struct urb * urb)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 */
ttusbir_process_ir_data(struct ttusbir * tt,uint8_t * buf)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
ttusbir_urb_complete(struct urb * urb)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
ttusbir_probe(struct usb_interface * intf,const struct usb_device_id * id)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
ttusbir_disconnect(struct usb_interface * intf)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
ttusbir_suspend(struct usb_interface * intf,pm_message_t message)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
ttusbir_resume(struct usb_interface * intf)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