em28xx-audio.c revision 758021bfa9ea25c58e62d2f68512628b19502ce7 
1/*
2 *  Empiatech em28x1 audio extension
3 *
4 *  Copyright (C) 2006 Markus Rechberger <mrechberger@gmail.com>
5 *
6 *  Copyright (C) 2007 Mauro Carvalho Chehab <mchehab@infradead.org>
7 *	- Port to work with the in-kernel driver
8 *	- Several cleanups
9 *
10 *  This driver is based on my previous au600 usb pstn audio driver
11 *  and inherits all the copyrights
12 *
13 *  This program is free software; you can redistribute it and/or modify
14 *  it under the terms of the GNU General Public License as published by
15 *  the Free Software Foundation; either version 2 of the License, or
16 *  (at your option) any later version.
17 *
18 *  This program is distributed in the hope that it will be useful,
19 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
20 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21 *  GNU General Public License for more details.
22 *
23 *  You should have received a copy of the GNU General Public License
24 *  along with this program; if not, write to the Free Software
25 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 */
27
28#include <linux/kernel.h>
29#include <linux/usb.h>
30#include <linux/init.h>
31#include <linux/sound.h>
32#include <linux/spinlock.h>
33#include <linux/soundcard.h>
34#include <linux/slab.h>
35#include <linux/vmalloc.h>
36#include <linux/proc_fs.h>
37#include <linux/module.h>
38#include <sound/core.h>
39#include <sound/pcm.h>
40#include <sound/pcm_params.h>
41#include <sound/info.h>
42#include <sound/initval.h>
43#include <sound/control.h>
44#include <media/v4l2-common.h>
45#include "em28xx.h"
46
47static int debug;
48module_param(debug, int, 0644);
49MODULE_PARM_DESC(debug, "activates debug info");
50
51#define dprintk(fmt, arg...) do {					\
52	    if (debug)							\
53		printk(KERN_INFO "em28xx-audio %s: " fmt,		\
54				  __func__, ##arg); 		\
55	} while (0)
56
57static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
58
59static int em28xx_isoc_audio_deinit(struct em28xx *dev)
60{
61	int i;
62
63	dprintk("Stopping isoc\n");
64	for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
65		usb_unlink_urb(dev->adev.urb[i]);
66		usb_free_urb(dev->adev.urb[i]);
67		dev->adev.urb[i] = NULL;
68	}
69
70	return 0;
71}
72
73static void em28xx_audio_isocirq(struct urb *urb)
74{
75	struct em28xx            *dev = urb->context;
76	int                      i;
77	unsigned int             oldptr;
78	int                      period_elapsed = 0;
79	int                      status;
80	unsigned char            *cp;
81	unsigned int             stride;
82	struct snd_pcm_substream *substream;
83	struct snd_pcm_runtime   *runtime;
84	if (dev->adev.capture_pcm_substream) {
85		substream = dev->adev.capture_pcm_substream;
86		runtime = substream->runtime;
87		stride = runtime->frame_bits >> 3;
88
89		for (i = 0; i < urb->number_of_packets; i++) {
90			int length =
91			    urb->iso_frame_desc[i].actual_length / stride;
92			cp = (unsigned char *)urb->transfer_buffer +
93			    urb->iso_frame_desc[i].offset;
94
95			if (!length)
96				continue;
97
98			oldptr = dev->adev.hwptr_done_capture;
99			if (oldptr + length >= runtime->buffer_size) {
100				unsigned int cnt =
101				    runtime->buffer_size - oldptr;
102				memcpy(runtime->dma_area + oldptr * stride, cp,
103				       cnt * stride);
104				memcpy(runtime->dma_area, cp + cnt * stride,
105				       length * stride - cnt * stride);
106			} else {
107				memcpy(runtime->dma_area + oldptr * stride, cp,
108				       length * stride);
109			}
110
111			snd_pcm_stream_lock(substream);
112
113			dev->adev.hwptr_done_capture += length;
114			if (dev->adev.hwptr_done_capture >=
115			    runtime->buffer_size)
116				dev->adev.hwptr_done_capture -=
117				    runtime->buffer_size;
118
119			dev->adev.capture_transfer_done += length;
120			if (dev->adev.capture_transfer_done >=
121			    runtime->period_size) {
122				dev->adev.capture_transfer_done -=
123				    runtime->period_size;
124				period_elapsed = 1;
125			}
126
127			snd_pcm_stream_unlock(substream);
128		}
129		if (period_elapsed)
130			snd_pcm_period_elapsed(substream);
131	}
132	urb->status = 0;
133
134	if (dev->adev.shutdown)
135		return;
136
137	status = usb_submit_urb(urb, GFP_ATOMIC);
138	if (status < 0) {
139		em28xx_errdev("resubmit of audio urb failed (error=%i)\n",
140			      status);
141	}
142	return;
143}
144
145static int em28xx_init_audio_isoc(struct em28xx *dev)
146{
147	int       i, errCode;
148	const int sb_size = EM28XX_NUM_AUDIO_PACKETS *
149			    EM28XX_AUDIO_MAX_PACKET_SIZE;
150
151	dprintk("Starting isoc transfers\n");
152
153	for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
154		struct urb *urb;
155		int j, k;
156
157		dev->adev.transfer_buffer[i] = kmalloc(sb_size, GFP_ATOMIC);
158		if (!dev->adev.transfer_buffer[i])
159			return -ENOMEM;
160
161		memset(dev->adev.transfer_buffer[i], 0x80, sb_size);
162		urb = usb_alloc_urb(EM28XX_NUM_AUDIO_PACKETS, GFP_ATOMIC);
163		if (!urb) {
164			em28xx_errdev("usb_alloc_urb failed!\n");
165			for (j = 0; j < i; j++) {
166				usb_free_urb(dev->adev.urb[j]);
167				kfree(dev->adev.transfer_buffer[j]);
168			}
169			return -ENOMEM;
170		}
171
172		urb->dev = dev->udev;
173		urb->context = dev;
174		urb->pipe = usb_rcvisocpipe(dev->udev, 0x83);
175		urb->transfer_flags = URB_ISO_ASAP;
176		urb->transfer_buffer = dev->adev.transfer_buffer[i];
177		urb->interval = 1;
178		urb->complete = em28xx_audio_isocirq;
179		urb->number_of_packets = EM28XX_NUM_AUDIO_PACKETS;
180		urb->transfer_buffer_length = sb_size;
181
182		for (j = k = 0; j < EM28XX_NUM_AUDIO_PACKETS;
183			     j++, k += EM28XX_AUDIO_MAX_PACKET_SIZE) {
184			urb->iso_frame_desc[j].offset = k;
185			urb->iso_frame_desc[j].length =
186			    EM28XX_AUDIO_MAX_PACKET_SIZE;
187		}
188		dev->adev.urb[i] = urb;
189	}
190
191	for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
192		errCode = usb_submit_urb(dev->adev.urb[i], GFP_ATOMIC);
193		if (errCode) {
194			em28xx_isoc_audio_deinit(dev);
195
196			return errCode;
197		}
198	}
199
200	return 0;
201}
202
203static int em28xx_cmd(struct em28xx *dev, int cmd, int arg)
204{
205	dprintk("%s transfer\n", (dev->adev.capture_stream == STREAM_ON) ?
206				 "stop" : "start");
207
208	switch (cmd) {
209	case EM28XX_CAPTURE_STREAM_EN:
210		if (dev->adev.capture_stream == STREAM_OFF && arg == 1) {
211			dev->adev.capture_stream = STREAM_ON;
212			em28xx_init_audio_isoc(dev);
213		} else if (dev->adev.capture_stream == STREAM_ON && arg == 0) {
214			dev->adev.capture_stream = STREAM_OFF;
215			em28xx_isoc_audio_deinit(dev);
216		} else {
217			printk(KERN_ERR "An underrun very likely occurred. "
218					"Ignoring it.\n");
219		}
220		return 0;
221	default:
222		return -EINVAL;
223	}
224}
225
226static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
227					size_t size)
228{
229	struct snd_pcm_runtime *runtime = subs->runtime;
230
231	dprintk("Alocating vbuffer\n");
232	if (runtime->dma_area) {
233		if (runtime->dma_bytes > size)
234			return 0;
235
236		vfree(runtime->dma_area);
237	}
238	runtime->dma_area = vmalloc(size);
239	if (!runtime->dma_area)
240		return -ENOMEM;
241
242	runtime->dma_bytes = size;
243
244	return 0;
245}
246
247static struct snd_pcm_hardware snd_em28xx_hw_capture = {
248	.info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
249		SNDRV_PCM_INFO_MMAP           |
250		SNDRV_PCM_INFO_INTERLEAVED    |
251		SNDRV_PCM_INFO_MMAP_VALID,
252
253	.formats = SNDRV_PCM_FMTBIT_S16_LE,
254
255	.rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_KNOT,
256
257	.rate_min = 48000,
258	.rate_max = 48000,
259	.channels_min = 2,
260	.channels_max = 2,
261	.buffer_bytes_max = 62720 * 8,	/* just about the value in usbaudio.c */
262	.period_bytes_min = 64,		/* 12544/2, */
263	.period_bytes_max = 12544,
264	.periods_min = 2,
265	.periods_max = 98,		/* 12544, */
266};
267
268static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
269{
270	struct em28xx *dev = snd_pcm_substream_chip(substream);
271	struct snd_pcm_runtime *runtime = substream->runtime;
272	int ret = 0;
273
274	dprintk("opening device and trying to acquire exclusive lock\n");
275
276	if (!dev) {
277		printk(KERN_ERR "BUG: em28xx can't find device struct."
278				" Can't proceed with open\n");
279		return -ENODEV;
280	}
281
282	/* Sets volume, mute, etc */
283
284	dev->mute = 0;
285	mutex_lock(&dev->lock);
286	ret = em28xx_audio_analog_set(dev);
287	mutex_unlock(&dev->lock);
288	if (ret < 0)
289		goto err;
290
291	runtime->hw = snd_em28xx_hw_capture;
292	if (dev->alt == 0 && dev->adev.users == 0) {
293		int errCode;
294		dev->alt = 7;
295		errCode = usb_set_interface(dev->udev, 0, 7);
296		dprintk("changing alternate number to 7\n");
297	}
298
299	dev->adev.users++;
300
301	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
302	dev->adev.capture_pcm_substream = substream;
303	runtime->private_data = dev;
304
305	return 0;
306err:
307	printk(KERN_ERR "Error while configuring em28xx mixer\n");
308	return ret;
309}
310
311static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
312{
313	struct em28xx *dev = snd_pcm_substream_chip(substream);
314	dev->adev.users--;
315
316	dprintk("closing device\n");
317
318	dev->mute = 1;
319	mutex_lock(&dev->lock);
320	em28xx_audio_analog_set(dev);
321	mutex_unlock(&dev->lock);
322
323	if (dev->adev.users == 0 && dev->adev.shutdown == 1) {
324		dprintk("audio users: %d\n", dev->adev.users);
325		dprintk("disabling audio stream!\n");
326		dev->adev.shutdown = 0;
327		dprintk("released lock\n");
328		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
329	}
330	return 0;
331}
332
333static int snd_em28xx_hw_capture_params(struct snd_pcm_substream *substream,
334					struct snd_pcm_hw_params *hw_params)
335{
336	unsigned int channels, rate, format;
337	int ret;
338
339	dprintk("Setting capture parameters\n");
340
341	ret = snd_pcm_alloc_vmalloc_buffer(substream,
342				params_buffer_bytes(hw_params));
343	format = params_format(hw_params);
344	rate = params_rate(hw_params);
345	channels = params_channels(hw_params);
346
347	/* TODO: set up em28xx audio chip to deliver the correct audio format,
348	   current default is 48000hz multiplexed => 96000hz mono
349	   which shouldn't matter since analogue TV only supports mono */
350	return 0;
351}
352
353static int snd_em28xx_hw_capture_free(struct snd_pcm_substream *substream)
354{
355	struct em28xx *dev = snd_pcm_substream_chip(substream);
356
357	dprintk("Stop capture, if needed\n");
358
359	if (dev->adev.capture_stream == STREAM_ON)
360		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
361
362	return 0;
363}
364
365static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
366{
367	return 0;
368}
369
370static int snd_em28xx_capture_trigger(struct snd_pcm_substream *substream,
371				      int cmd)
372{
373	struct em28xx *dev = snd_pcm_substream_chip(substream);
374
375	dprintk("Should %s capture\n", (cmd == SNDRV_PCM_TRIGGER_START)?
376				       "start": "stop");
377	switch (cmd) {
378	case SNDRV_PCM_TRIGGER_START:
379		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 1);
380		return 0;
381	case SNDRV_PCM_TRIGGER_STOP:
382		dev->adev.shutdown = 1;
383		return 0;
384	default:
385		return -EINVAL;
386	}
387}
388
389static snd_pcm_uframes_t snd_em28xx_capture_pointer(struct snd_pcm_substream
390						    *substream)
391{
392	struct em28xx *dev;
393
394	snd_pcm_uframes_t hwptr_done;
395	dev = snd_pcm_substream_chip(substream);
396	hwptr_done = dev->adev.hwptr_done_capture;
397
398	return hwptr_done;
399}
400
401static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs,
402					     unsigned long offset)
403{
404	void *pageptr = subs->runtime->dma_area + offset;
405
406	return vmalloc_to_page(pageptr);
407}
408
409static struct snd_pcm_ops snd_em28xx_pcm_capture = {
410	.open      = snd_em28xx_capture_open,
411	.close     = snd_em28xx_pcm_close,
412	.ioctl     = snd_pcm_lib_ioctl,
413	.hw_params = snd_em28xx_hw_capture_params,
414	.hw_free   = snd_em28xx_hw_capture_free,
415	.prepare   = snd_em28xx_prepare,
416	.trigger   = snd_em28xx_capture_trigger,
417	.pointer   = snd_em28xx_capture_pointer,
418	.page      = snd_pcm_get_vmalloc_page,
419};
420
421static int em28xx_audio_init(struct em28xx *dev)
422{
423	struct em28xx_audio *adev = &dev->adev;
424	struct snd_pcm      *pcm;
425	struct snd_card     *card;
426	static int          devnr;
427	int                 err;
428
429	if (dev->has_alsa_audio != 1) {
430		/* This device does not support the extension (in this case
431		   the device is expecting the snd-usb-audio module or
432		   doesn't have analog audio support at all) */
433		return 0;
434	}
435
436	printk(KERN_INFO "em28xx-audio.c: probing for em28x1 "
437			 "non standard usbaudio\n");
438	printk(KERN_INFO "em28xx-audio.c: Copyright (C) 2006 Markus "
439			 "Rechberger\n");
440
441	err = snd_card_create(index[devnr], "Em28xx Audio", THIS_MODULE, 0,
442			      &card);
443	if (err < 0)
444		return err;
445
446	spin_lock_init(&adev->slock);
447	err = snd_pcm_new(card, "Em28xx Audio", 0, 0, 1, &pcm);
448	if (err < 0) {
449		snd_card_free(card);
450		return err;
451	}
452
453	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_em28xx_pcm_capture);
454	pcm->info_flags = 0;
455	pcm->private_data = dev;
456	strcpy(pcm->name, "Empia 28xx Capture");
457	strcpy(card->driver, "Empia Em28xx Audio");
458	strcpy(card->shortname, "Em28xx Audio");
459	strcpy(card->longname, "Empia Em28xx Audio");
460
461	err = snd_card_register(card);
462	if (err < 0) {
463		snd_card_free(card);
464		return err;
465	}
466	adev->sndcard = card;
467	adev->udev = dev->udev;
468
469	return 0;
470}
471
472static int em28xx_audio_fini(struct em28xx *dev)
473{
474	if (dev == NULL)
475		return 0;
476
477	if (dev->has_alsa_audio != 1) {
478		/* This device does not support the extension (in this case
479		   the device is expecting the snd-usb-audio module or
480		   doesn't have analog audio support at all) */
481		return 0;
482	}
483
484	if (dev->adev.sndcard) {
485		snd_card_free(dev->adev.sndcard);
486		dev->adev.sndcard = NULL;
487	}
488
489	return 0;
490}
491
492static struct em28xx_ops audio_ops = {
493	.id   = EM28XX_AUDIO,
494	.name = "Em28xx Audio Extension",
495	.init = em28xx_audio_init,
496	.fini = em28xx_audio_fini,
497};
498
499static int __init em28xx_alsa_register(void)
500{
501	return em28xx_register_extension(&audio_ops);
502}
503
504static void __exit em28xx_alsa_unregister(void)
505{
506	em28xx_unregister_extension(&audio_ops);
507}
508
509MODULE_LICENSE("GPL");
510MODULE_AUTHOR("Markus Rechberger <mrechberger@gmail.com>");
511MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
512MODULE_DESCRIPTION("Em28xx Audio driver");
513
514module_init(em28xx_alsa_register);
515module_exit(em28xx_alsa_unregister);
516