2 * Empiatech em28x1 audio extension
4 * Copyright (C) 2006 Markus Rechberger <mrechberger@gmail.com>
6 * Copyright (C) 2007 Mauro Carvalho Chehab <mchehab@infradead.org>
7 * - Port to work with the in-kernel driver
10 * This driver is based on my previous au600 usb pstn audio driver
11 * and inherits all the copyrights
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.
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.
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.
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>
48 module_param(debug, int, 0644);
49 MODULE_PARM_DESC(debug, "activates debug info");
51 #define dprintk(fmt, arg...) do { \
53 printk(KERN_INFO "em28xx-audio %s: " fmt, \
57 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
59 static int em28xx_isoc_audio_deinit(struct em28xx *dev)
63 dprintk("Stopping isoc\n");
64 for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
65 usb_kill_urb(dev->adev->urb[i]);
66 usb_free_urb(dev->adev->urb[i]);
67 dev->adev->urb[i] = NULL;
73 static void em28xx_audio_isocirq(struct urb *urb)
75 struct em28xx *dev = urb->context;
79 int period_elapsed = 0;
83 struct snd_pcm_substream *substream;
84 struct snd_pcm_runtime *runtime;
85 if (dev->adev->capture_pcm_substream) {
86 substream = dev->adev->capture_pcm_substream;
87 runtime = substream->runtime;
88 stride = runtime->frame_bits >> 3;
90 for (i = 0; i < urb->number_of_packets; i++) {
92 urb->iso_frame_desc[i].actual_length / stride;
93 cp = (unsigned char *)urb->transfer_buffer +
94 urb->iso_frame_desc[i].offset;
99 spin_lock_irqsave(&dev->adev->slock, flags);
101 oldptr = dev->adev->hwptr_done_capture;
102 dev->adev->hwptr_done_capture += length;
103 if (dev->adev->hwptr_done_capture >=
104 runtime->buffer_size)
105 dev->adev->hwptr_done_capture -=
106 runtime->buffer_size;
108 dev->adev->capture_transfer_done += length;
109 if (dev->adev->capture_transfer_done >=
110 runtime->period_size) {
111 dev->adev->capture_transfer_done -=
112 runtime->period_size;
116 spin_unlock_irqrestore(&dev->adev->slock, flags);
118 if (oldptr + length >= runtime->buffer_size) {
120 runtime->buffer_size - oldptr - 1;
121 memcpy(runtime->dma_area + oldptr * stride, cp,
123 memcpy(runtime->dma_area, cp + cnt,
124 length * stride - cnt * stride);
126 memcpy(runtime->dma_area + oldptr * stride, cp,
131 snd_pcm_period_elapsed(substream);
135 if (dev->adev->shutdown)
138 status = usb_submit_urb(urb, GFP_ATOMIC);
140 em28xx_errdev("resubmit of audio urb failed (error=%i)\n",
146 static int em28xx_init_audio_isoc(struct em28xx *dev)
149 const int sb_size = EM28XX_NUM_AUDIO_PACKETS *
150 EM28XX_AUDIO_MAX_PACKET_SIZE;
152 dprintk("Starting isoc transfers\n");
154 for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
158 dev->adev->transfer_buffer[i] = kmalloc(sb_size, GFP_ATOMIC);
159 if (!dev->adev->transfer_buffer[i])
162 memset(dev->adev->transfer_buffer[i], 0x80, sb_size);
163 urb = usb_alloc_urb(EM28XX_NUM_AUDIO_PACKETS, GFP_ATOMIC);
167 urb->dev = dev->udev;
169 urb->pipe = usb_rcvisocpipe(dev->udev, 0x83);
170 urb->transfer_flags = URB_ISO_ASAP;
171 urb->transfer_buffer = dev->adev->transfer_buffer[i];
173 urb->complete = em28xx_audio_isocirq;
174 urb->number_of_packets = EM28XX_NUM_AUDIO_PACKETS;
175 urb->transfer_buffer_length = sb_size;
177 for (j = k = 0; j < EM28XX_NUM_AUDIO_PACKETS;
178 j++, k += EM28XX_AUDIO_MAX_PACKET_SIZE) {
179 urb->iso_frame_desc[j].offset = k;
180 urb->iso_frame_desc[j].length =
181 EM28XX_AUDIO_MAX_PACKET_SIZE;
183 dev->adev->urb[i] = urb;
186 for (i = 0; i < EM28XX_AUDIO_BUFS; i++) {
187 errCode = usb_submit_urb(dev->adev->urb[i], GFP_ATOMIC);
189 em28xx_isoc_audio_deinit(dev);
198 static int em28xx_cmd(struct em28xx *dev, int cmd, int arg)
200 dprintk("%s transfer\n", (dev->adev->capture_stream == STREAM_ON)?
204 case EM28XX_CAPTURE_STREAM_EN:
205 if (dev->adev->capture_stream == STREAM_OFF && arg == 1) {
206 dev->adev->capture_stream = STREAM_ON;
207 em28xx_init_audio_isoc(dev);
208 } else if (dev->adev->capture_stream == STREAM_ON && arg == 0) {
209 dev->adev->capture_stream = STREAM_OFF;
210 em28xx_isoc_audio_deinit(dev);
212 printk(KERN_ERR "An underrun very likely occurred. "
221 static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
224 struct snd_pcm_runtime *runtime = subs->runtime;
226 dprintk("Alocating vbuffer\n");
227 if (runtime->dma_area) {
228 if (runtime->dma_bytes > size)
231 vfree(runtime->dma_area);
233 runtime->dma_area = vmalloc(size);
234 if (!runtime->dma_area)
237 runtime->dma_bytes = size;
242 static struct snd_pcm_hardware snd_em28xx_hw_capture = {
243 .info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
244 SNDRV_PCM_INFO_MMAP |
245 SNDRV_PCM_INFO_INTERLEAVED |
246 SNDRV_PCM_INFO_MMAP_VALID,
248 .formats = SNDRV_PCM_FMTBIT_S16_LE,
250 .rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_KNOT,
256 .buffer_bytes_max = 62720 * 8, /* just about the value in usbaudio.c */
257 .period_bytes_min = 64, /* 12544/2, */
258 .period_bytes_max = 12544,
260 .periods_max = 98, /* 12544, */
263 static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
265 struct em28xx *dev = snd_pcm_substream_chip(substream);
266 struct snd_pcm_runtime *runtime = substream->runtime;
269 dprintk("opening device and trying to acquire exclusive lock\n");
271 /* Sets volume, mute, etc */
274 mutex_lock(&dev->lock);
275 ret = em28xx_audio_analog_set(dev);
276 mutex_unlock(&dev->lock);
280 runtime->hw = snd_em28xx_hw_capture;
281 if (dev->alt == 0 && dev->adev->users == 0) {
284 errCode = usb_set_interface(dev->udev, 0, 7);
285 dprintk("changing alternate number to 7\n");
290 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
291 dev->adev->capture_pcm_substream = substream;
292 runtime->private_data = dev;
296 printk(KERN_ERR "Error while configuring em28xx mixer\n");
300 static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
302 struct em28xx *dev = snd_pcm_substream_chip(substream);
305 dprintk("closing device\n");
308 mutex_lock(&dev->lock);
309 em28xx_audio_analog_set(dev);
310 mutex_unlock(&dev->lock);
312 if (dev->adev->users == 0 && dev->adev->shutdown == 1) {
313 dprintk("audio users: %d\n", dev->adev->users);
314 dprintk("disabling audio stream!\n");
315 dev->adev->shutdown = 0;
316 dprintk("released lock\n");
317 em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
322 static int snd_em28xx_hw_capture_params(struct snd_pcm_substream *substream,
323 struct snd_pcm_hw_params *hw_params)
325 unsigned int channels, rate, format;
328 dprintk("Setting capture parameters\n");
330 ret = snd_pcm_alloc_vmalloc_buffer(substream,
331 params_buffer_bytes(hw_params));
332 format = params_format(hw_params);
333 rate = params_rate(hw_params);
334 channels = params_channels(hw_params);
336 /* TODO: set up em28xx audio chip to deliver the correct audio format,
337 current default is 48000hz multiplexed => 96000hz mono
338 which shouldn't matter since analogue TV only supports mono */
342 static int snd_em28xx_hw_capture_free(struct snd_pcm_substream *substream)
344 struct em28xx *dev = snd_pcm_substream_chip(substream);
346 dprintk("Stop capture, if needed\n");
348 if (dev->adev->capture_stream == STREAM_ON)
349 em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
354 static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
359 static int snd_em28xx_capture_trigger(struct snd_pcm_substream *substream,
362 struct em28xx *dev = snd_pcm_substream_chip(substream);
364 dprintk("Should %s capture\n", (cmd == SNDRV_PCM_TRIGGER_START)?
367 case SNDRV_PCM_TRIGGER_START:
368 em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 1);
370 case SNDRV_PCM_TRIGGER_STOP:
371 dev->adev->shutdown = 1;
378 static snd_pcm_uframes_t snd_em28xx_capture_pointer(struct snd_pcm_substream
383 snd_pcm_uframes_t hwptr_done;
384 dev = snd_pcm_substream_chip(substream);
385 hwptr_done = dev->adev->hwptr_done_capture;
390 static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs,
391 unsigned long offset)
393 void *pageptr = subs->runtime->dma_area + offset;
395 return vmalloc_to_page(pageptr);
398 static struct snd_pcm_ops snd_em28xx_pcm_capture = {
399 .open = snd_em28xx_capture_open,
400 .close = snd_em28xx_pcm_close,
401 .ioctl = snd_pcm_lib_ioctl,
402 .hw_params = snd_em28xx_hw_capture_params,
403 .hw_free = snd_em28xx_hw_capture_free,
404 .prepare = snd_em28xx_prepare,
405 .trigger = snd_em28xx_capture_trigger,
406 .pointer = snd_em28xx_capture_pointer,
407 .page = snd_pcm_get_vmalloc_page,
410 static int em28xx_audio_init(struct em28xx *dev)
412 struct em28xx_audio *adev;
414 struct snd_card *card;
418 printk(KERN_INFO "em28xx-audio.c: probing for em28x1 "
419 "non standard usbaudio\n");
420 printk(KERN_INFO "em28xx-audio.c: Copyright (C) 2006 Markus "
423 adev = kzalloc(sizeof(*adev), GFP_KERNEL);
425 printk(KERN_ERR "em28xx-audio.c: out of memory\n");
428 card = snd_card_new(index[devnr], "Em28xx Audio", THIS_MODULE, 0);
434 spin_lock_init(&adev->slock);
435 ret = snd_pcm_new(card, "Em28xx Audio", 0, 0, 1, &pcm);
436 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_em28xx_pcm_capture);
438 pcm->private_data = dev;
439 strcpy(pcm->name, "Empia 28xx Capture");
440 strcpy(card->driver, "Empia Em28xx Audio");
441 strcpy(card->shortname, "Em28xx Audio");
442 strcpy(card->longname, "Empia Em28xx Audio");
444 err = snd_card_register(card);
449 adev->sndcard = card;
450 adev->udev = dev->udev;
456 static int em28xx_audio_fini(struct em28xx *dev)
462 snd_card_free(dev->adev->sndcard);
470 static struct em28xx_ops audio_ops = {
472 .name = "Em28xx Audio Extension",
473 .init = em28xx_audio_init,
474 .fini = em28xx_audio_fini,
477 static int __init em28xx_alsa_register(void)
479 return em28xx_register_extension(&audio_ops);
482 static void __exit em28xx_alsa_unregister(void)
484 em28xx_unregister_extension(&audio_ops);
487 MODULE_LICENSE("GPL");
488 MODULE_AUTHOR("Markus Rechberger <mrechberger@gmail.com>");
489 MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
490 MODULE_DESCRIPTION("Em28xx Audio driver");
492 module_init(em28xx_alsa_register);
493 module_exit(em28xx_alsa_unregister);