1 /*
2  * Copyright (c) 2013 Federico Simoncelli
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions, and the following disclaimer,
10  *    without modification.
11  * 2. The name of the author may not be used to endorse or promote products
12  *    derived from this software without specific prior written permission.
13  *
14  * Alternatively, this software may be distributed under the terms of the
15  * GNU General Public License ("GPL").
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 /*
30  * Fushicai USBTV007 Audio-Video Grabber Driver
31  *
32  * Product web site:
33  * http://www.fushicai.com/products_detail/&productId=d05449ee-b690-42f9-a661-aa7353894bed.html
34  *
35  * No physical hardware was harmed running Windows during the
36  * reverse-engineering activity
37  */
38 
39 #include <sound/core.h>
40 #include <sound/initval.h>
41 #include <sound/ac97_codec.h>
42 #include <sound/pcm_params.h>
43 
44 #include "usbtv.h"
45 
46 static const struct snd_pcm_hardware snd_usbtv_digital_hw = {
47 	.info = SNDRV_PCM_INFO_BATCH |
48 		SNDRV_PCM_INFO_MMAP |
49 		SNDRV_PCM_INFO_INTERLEAVED |
50 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
51 		SNDRV_PCM_INFO_MMAP_VALID,
52 	.formats = SNDRV_PCM_FMTBIT_S16_LE,
53 	.rates = SNDRV_PCM_RATE_48000,
54 	.rate_min = 48000,
55 	.rate_max = 48000,
56 	.channels_min = 2,
57 	.channels_max = 2,
58 	.period_bytes_min = 11059,
59 	.period_bytes_max = 13516,
60 	.periods_min = 2,
61 	.periods_max = 98,
62 	.buffer_bytes_max = 62720 * 8, /* value in usbaudio.c */
63 };
64 
65 static int snd_usbtv_pcm_open(struct snd_pcm_substream *substream)
66 {
67 	struct usbtv *chip = snd_pcm_substream_chip(substream);
68 	struct snd_pcm_runtime *runtime = substream->runtime;
69 
70 	chip->snd_substream = substream;
71 	runtime->hw = snd_usbtv_digital_hw;
72 
73 	return 0;
74 }
75 
76 static int snd_usbtv_pcm_close(struct snd_pcm_substream *substream)
77 {
78 	struct usbtv *chip = snd_pcm_substream_chip(substream);
79 
80 	if (atomic_read(&chip->snd_stream)) {
81 		atomic_set(&chip->snd_stream, 0);
82 		schedule_work(&chip->snd_trigger);
83 	}
84 
85 	return 0;
86 }
87 
88 static int snd_usbtv_prepare(struct snd_pcm_substream *substream)
89 {
90 	struct usbtv *chip = snd_pcm_substream_chip(substream);
91 
92 	chip->snd_buffer_pos = 0;
93 	chip->snd_period_pos = 0;
94 
95 	return 0;
96 }
97 
98 static void usbtv_audio_urb_received(struct urb *urb)
99 {
100 	struct usbtv *chip = urb->context;
101 	struct snd_pcm_substream *substream = chip->snd_substream;
102 	struct snd_pcm_runtime *runtime = substream->runtime;
103 	size_t i, frame_bytes, chunk_length, buffer_pos, period_pos;
104 	int period_elapsed;
105 	unsigned long flags;
106 	void *urb_current;
107 
108 	switch (urb->status) {
109 	case 0:
110 	case -ETIMEDOUT:
111 		break;
112 	case -ENOENT:
113 	case -EPROTO:
114 	case -ECONNRESET:
115 	case -ESHUTDOWN:
116 		return;
117 	default:
118 		dev_warn(chip->dev, "unknown audio urb status %i\n",
119 			urb->status);
120 	}
121 
122 	if (!atomic_read(&chip->snd_stream))
123 		return;
124 
125 	frame_bytes = runtime->frame_bits >> 3;
126 	chunk_length = USBTV_CHUNK / frame_bytes;
127 
128 	buffer_pos = chip->snd_buffer_pos;
129 	period_pos = chip->snd_period_pos;
130 	period_elapsed = 0;
131 
132 	for (i = 0; i < urb->actual_length; i += USBTV_CHUNK_SIZE) {
133 		urb_current = urb->transfer_buffer + i + USBTV_AUDIO_HDRSIZE;
134 
135 		if (buffer_pos + chunk_length >= runtime->buffer_size) {
136 			size_t cnt = (runtime->buffer_size - buffer_pos) *
137 				frame_bytes;
138 			memcpy(runtime->dma_area + buffer_pos * frame_bytes,
139 				urb_current, cnt);
140 			memcpy(runtime->dma_area, urb_current + cnt,
141 				chunk_length * frame_bytes - cnt);
142 		} else {
143 			memcpy(runtime->dma_area + buffer_pos * frame_bytes,
144 				urb_current, chunk_length * frame_bytes);
145 		}
146 
147 		buffer_pos += chunk_length;
148 		period_pos += chunk_length;
149 
150 		if (buffer_pos >= runtime->buffer_size)
151 			buffer_pos -= runtime->buffer_size;
152 
153 		if (period_pos >= runtime->period_size) {
154 			period_pos -= runtime->period_size;
155 			period_elapsed = 1;
156 		}
157 	}
158 
159 	snd_pcm_stream_lock_irqsave(substream, flags);
160 
161 	chip->snd_buffer_pos = buffer_pos;
162 	chip->snd_period_pos = period_pos;
163 
164 	snd_pcm_stream_unlock_irqrestore(substream, flags);
165 
166 	if (period_elapsed)
167 		snd_pcm_period_elapsed(substream);
168 
169 	usb_submit_urb(urb, GFP_ATOMIC);
170 }
171 
172 static int usbtv_audio_start(struct usbtv *chip)
173 {
174 	unsigned int pipe;
175 	static const u16 setup[][2] = {
176 		/* These seem to enable the device. */
177 		{ USBTV_BASE + 0x0008, 0x0001 },
178 		{ USBTV_BASE + 0x01d0, 0x00ff },
179 		{ USBTV_BASE + 0x01d9, 0x0002 },
180 
181 		{ USBTV_BASE + 0x01da, 0x0013 },
182 		{ USBTV_BASE + 0x01db, 0x0012 },
183 		{ USBTV_BASE + 0x01e9, 0x0002 },
184 		{ USBTV_BASE + 0x01ec, 0x006c },
185 		{ USBTV_BASE + 0x0294, 0x0020 },
186 		{ USBTV_BASE + 0x0255, 0x00cf },
187 		{ USBTV_BASE + 0x0256, 0x0020 },
188 		{ USBTV_BASE + 0x01eb, 0x0030 },
189 		{ USBTV_BASE + 0x027d, 0x00a6 },
190 		{ USBTV_BASE + 0x0280, 0x0011 },
191 		{ USBTV_BASE + 0x0281, 0x0040 },
192 		{ USBTV_BASE + 0x0282, 0x0011 },
193 		{ USBTV_BASE + 0x0283, 0x0040 },
194 		{ 0xf891, 0x0010 },
195 
196 		/* this sets the input from composite */
197 		{ USBTV_BASE + 0x0284, 0x00aa },
198 	};
199 
200 	chip->snd_bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
201 	if (chip->snd_bulk_urb == NULL)
202 		goto err_alloc_urb;
203 
204 	pipe = usb_rcvbulkpipe(chip->udev, USBTV_AUDIO_ENDP);
205 
206 	chip->snd_bulk_urb->transfer_buffer = kzalloc(
207 		USBTV_AUDIO_URBSIZE, GFP_KERNEL);
208 	if (chip->snd_bulk_urb->transfer_buffer == NULL)
209 		goto err_transfer_buffer;
210 
211 	usb_fill_bulk_urb(chip->snd_bulk_urb, chip->udev, pipe,
212 		chip->snd_bulk_urb->transfer_buffer, USBTV_AUDIO_URBSIZE,
213 		usbtv_audio_urb_received, chip);
214 
215 	/* starting the stream */
216 	usbtv_set_regs(chip, setup, ARRAY_SIZE(setup));
217 
218 	usb_clear_halt(chip->udev, pipe);
219 	usb_submit_urb(chip->snd_bulk_urb, GFP_ATOMIC);
220 
221 	return 0;
222 
223 err_transfer_buffer:
224 	usb_free_urb(chip->snd_bulk_urb);
225 	chip->snd_bulk_urb = NULL;
226 
227 err_alloc_urb:
228 	return -ENOMEM;
229 }
230 
231 static int usbtv_audio_stop(struct usbtv *chip)
232 {
233 	static const u16 setup[][2] = {
234 	/* The original windows driver sometimes sends also:
235 	 *   { USBTV_BASE + 0x00a2, 0x0013 }
236 	 * but it seems useless and its real effects are untested at
237 	 * the moment.
238 	 */
239 		{ USBTV_BASE + 0x027d, 0x0000 },
240 		{ USBTV_BASE + 0x0280, 0x0010 },
241 		{ USBTV_BASE + 0x0282, 0x0010 },
242 	};
243 
244 	if (chip->snd_bulk_urb) {
245 		usb_kill_urb(chip->snd_bulk_urb);
246 		kfree(chip->snd_bulk_urb->transfer_buffer);
247 		usb_free_urb(chip->snd_bulk_urb);
248 		chip->snd_bulk_urb = NULL;
249 	}
250 
251 	usbtv_set_regs(chip, setup, ARRAY_SIZE(setup));
252 
253 	return 0;
254 }
255 
256 void usbtv_audio_suspend(struct usbtv *usbtv)
257 {
258 	if (atomic_read(&usbtv->snd_stream) && usbtv->snd_bulk_urb)
259 		usb_kill_urb(usbtv->snd_bulk_urb);
260 }
261 
262 void usbtv_audio_resume(struct usbtv *usbtv)
263 {
264 	if (atomic_read(&usbtv->snd_stream) && usbtv->snd_bulk_urb)
265 		usb_submit_urb(usbtv->snd_bulk_urb, GFP_ATOMIC);
266 }
267 
268 static void snd_usbtv_trigger(struct work_struct *work)
269 {
270 	struct usbtv *chip = container_of(work, struct usbtv, snd_trigger);
271 
272 	if (!chip->snd)
273 		return;
274 
275 	if (atomic_read(&chip->snd_stream))
276 		usbtv_audio_start(chip);
277 	else
278 		usbtv_audio_stop(chip);
279 }
280 
281 static int snd_usbtv_card_trigger(struct snd_pcm_substream *substream, int cmd)
282 {
283 	struct usbtv *chip = snd_pcm_substream_chip(substream);
284 
285 	switch (cmd) {
286 	case SNDRV_PCM_TRIGGER_START:
287 	case SNDRV_PCM_TRIGGER_RESUME:
288 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
289 		atomic_set(&chip->snd_stream, 1);
290 		break;
291 	case SNDRV_PCM_TRIGGER_STOP:
292 	case SNDRV_PCM_TRIGGER_SUSPEND:
293 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
294 		atomic_set(&chip->snd_stream, 0);
295 		break;
296 	default:
297 		return -EINVAL;
298 	}
299 
300 	schedule_work(&chip->snd_trigger);
301 
302 	return 0;
303 }
304 
305 static snd_pcm_uframes_t snd_usbtv_pointer(struct snd_pcm_substream *substream)
306 {
307 	struct usbtv *chip = snd_pcm_substream_chip(substream);
308 
309 	return chip->snd_buffer_pos;
310 }
311 
312 static const struct snd_pcm_ops snd_usbtv_pcm_ops = {
313 	.open = snd_usbtv_pcm_open,
314 	.close = snd_usbtv_pcm_close,
315 	.prepare = snd_usbtv_prepare,
316 	.trigger = snd_usbtv_card_trigger,
317 	.pointer = snd_usbtv_pointer,
318 };
319 
320 int usbtv_audio_init(struct usbtv *usbtv)
321 {
322 	int rv;
323 	struct snd_card *card;
324 	struct snd_pcm *pcm;
325 
326 	INIT_WORK(&usbtv->snd_trigger, snd_usbtv_trigger);
327 	atomic_set(&usbtv->snd_stream, 0);
328 
329 	rv = snd_card_new(&usbtv->udev->dev, SNDRV_DEFAULT_IDX1, "usbtv",
330 		THIS_MODULE, 0, &card);
331 	if (rv < 0)
332 		return rv;
333 
334 	strscpy(card->driver, usbtv->dev->driver->name, sizeof(card->driver));
335 	strscpy(card->shortname, "usbtv", sizeof(card->shortname));
336 	snprintf(card->longname, sizeof(card->longname),
337 		"USBTV Audio at bus %d device %d", usbtv->udev->bus->busnum,
338 		usbtv->udev->devnum);
339 
340 	snd_card_set_dev(card, usbtv->dev);
341 
342 	usbtv->snd = card;
343 
344 	rv = snd_pcm_new(card, "USBTV Audio", 0, 0, 1, &pcm);
345 	if (rv < 0)
346 		goto err;
347 
348 	strscpy(pcm->name, "USBTV Audio Input", sizeof(pcm->name));
349 	pcm->info_flags = 0;
350 	pcm->private_data = usbtv;
351 
352 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_usbtv_pcm_ops);
353 	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
354 		NULL, USBTV_AUDIO_BUFFER, USBTV_AUDIO_BUFFER);
355 
356 	rv = snd_card_register(card);
357 	if (rv)
358 		goto err;
359 
360 	return 0;
361 
362 err:
363 	usbtv->snd = NULL;
364 	snd_card_free(card);
365 
366 	return rv;
367 }
368 
369 void usbtv_audio_free(struct usbtv *usbtv)
370 {
371 	cancel_work_sync(&usbtv->snd_trigger);
372 
373 	if (usbtv->snd && usbtv->udev) {
374 		snd_card_free_when_closed(usbtv->snd);
375 		usbtv->snd = NULL;
376 	}
377 }
378