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
39struct 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
56static 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
63static 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
81static 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 */
94static 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 */
122static 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
172static 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
197static 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_protocols = 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;
349out3:
350	rc_unregister_device(rc);
351	rc = NULL;
352out2:
353	led_classdev_unregister(&tt->led);
354out:
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
373static 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
395static 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
409static 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
428static const struct usb_device_id ttusbir_table[] = {
429	{ USB_DEVICE(0x0b48, 0x2003) },
430	{ }
431};
432
433static 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
443module_usb_driver(ttusbir_driver);
444
445MODULE_DESCRIPTION(DRIVER_DESC);
446MODULE_AUTHOR("Sean Young <sean@mess.org>");
447MODULE_LICENSE("GPL");
448MODULE_DEVICE_TABLE(usb, ttusbir_table);
449
450