em28xx-audio.c

trident tm5600的linux驱动

#endif
{
	struct em28xx *dev = snd_pcm_substream_chip(substream);
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
	snd_pcm_runtime_t *runtime = substream->runtime;
#else
	struct snd_pcm_runtime *runtime = substream->runtime;
#endif
	int ret = 0;

	dprintk("opening device and trying to acquire exclusive lock\n");

	if (!dev) {
		printk(KERN_ERR "BUG: em28xx can't find device struct."
				" Can't proceed with open\n");
		return -ENODEV;
	}

	/* Sets volume, mute, etc */

	dev->mute = 0;
	mutex_lock(&dev->lock);
	ret = em28xx_audio_analog_set(dev);
	mutex_unlock(&dev->lock);
	if (ret < 0)
		goto err;

	runtime->hw = snd_em28xx_hw_capture;
	if (dev->alt == 0 && dev->adev->users == 0) {
		int errCode;
		dev->alt = 7;
		errCode = usb_set_interface(dev->udev, 0, 7);
		dprintk("changing alternate number to 7\n");
	}

	dev->adev->users++;

	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
	dev->adev->capture_pcm_substream = substream;
	runtime->private_data = dev;

	return 0;
err:
	printk(KERN_ERR "Error while configuring em28xx mixer\n");
	return ret;
}

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
static int snd_em28xx_pcm_close(snd_pcm_substream_t *substream)
#else
static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
#endif
{
	struct em28xx *dev = snd_pcm_substream_chip(substream);
	dev->adev->users--;

	dprintk("closing device\n");

	dev->mute = 1;
	mutex_lock(&dev->lock);
	em28xx_audio_analog_set(dev);
	mutex_unlock(&dev->lock);

	if (dev->adev->users == 0 && dev->adev->shutdown == 1) {
		dprintk("audio users: %d\n", dev->adev->users);
		dprintk("disabling audio stream!\n");
		dev->adev->shutdown = 0;
		dprintk("released lock\n");
		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);
	}
	return 0;
}

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
static int snd_em28xx_hw_capture_params(snd_pcm_substream_t *substream,
					snd_pcm_hw_params_t *hw_params)
#else
static int snd_em28xx_hw_capture_params(struct snd_pcm_substream *substream,
					struct snd_pcm_hw_params *hw_params)
#endif
{
	unsigned int channels, rate, format;
	int ret;

	dprintk("Setting capture parameters\n");

	ret = snd_pcm_alloc_vmalloc_buffer(substream,
				params_buffer_bytes(hw_params));
	format = params_format(hw_params);
	rate = params_rate(hw_params);
	channels = params_channels(hw_params);

	/* TODO: set up em28xx audio chip to deliver the correct audio format,
	   current default is 48000hz multiplexed => 96000hz mono
	   which shouldn't matter since analogue TV only supports mono */
	return 0;
}

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
static int snd_em28xx_hw_capture_free(snd_pcm_substream_t *substream)
#else
static int snd_em28xx_hw_capture_free(struct snd_pcm_substream *substream)
#endif
{
	struct em28xx *dev = snd_pcm_substream_chip(substream);

	dprintk("Stop capture, if needed\n");

	if (dev->adev->capture_stream == STREAM_ON)
		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 0);

	return 0;
}

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
static int snd_em28xx_prepare(snd_pcm_substream_t *substream)
#else
static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
#endif
{
	return 0;
}

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
static int snd_em28xx_capture_trigger(snd_pcm_substream_t *substream, int cmd)
#else
static int snd_em28xx_capture_trigger(struct snd_pcm_substream *substream,
				      int cmd)
#endif
{
	struct em28xx *dev = snd_pcm_substream_chip(substream);

	dprintk("Should %s capture\n", (cmd == SNDRV_PCM_TRIGGER_START)?
				       "start": "stop");
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
		em28xx_cmd(dev, EM28XX_CAPTURE_STREAM_EN, 1);
		return 0;
	case SNDRV_PCM_TRIGGER_STOP:
		dev->adev->shutdown = 1;
		return 0;
	default:
		return -EINVAL;
	}
}

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
static snd_pcm_uframes_t snd_em28xx_capture_pointer(snd_pcm_substream_t
						    *substream)
#else
static snd_pcm_uframes_t snd_em28xx_capture_pointer(struct snd_pcm_substream
						    *substream)
#endif
{
	struct em28xx *dev;

	snd_pcm_uframes_t hwptr_done;
	dev = snd_pcm_substream_chip(substream);
	hwptr_done = dev->adev->hwptr_done_capture;

	return hwptr_done;
}

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
static struct page *snd_pcm_get_vmalloc_page(snd_pcm_substream_t *subs,
					     unsigned long offset)
#else
static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs,
					     unsigned long offset)
#endif
{
	void *pageptr = subs->runtime->dma_area + offset;

	return vmalloc_to_page(pageptr);
}

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
static snd_pcm_ops_t snd_em28xx_pcm_capture = {
#else
static struct snd_pcm_ops snd_em28xx_pcm_capture = {
#endif
	.open      = snd_em28xx_capture_open,
	.close     = snd_em28xx_pcm_close,
	.ioctl     = snd_pcm_lib_ioctl,
	.hw_params = snd_em28xx_hw_capture_params,
	.hw_free   = snd_em28xx_hw_capture_free,
	.prepare   = snd_em28xx_prepare,
	.trigger   = snd_em28xx_capture_trigger,
	.pointer   = snd_em28xx_capture_pointer,
	.page      = snd_pcm_get_vmalloc_page,
};

static int em28xx_audio_init(struct em28xx *dev)
{
	struct em28xx_audio *adev;
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 16)
	snd_pcm_t           *pcm;
	snd_card_t          *card;
#else
	struct snd_pcm      *pcm;
	struct snd_card     *card;
#endif
	static int          devnr;
	int                 ret, err;

	if (dev->has_audio_class) {
		/* This device does not support the extension (in this case
		   the device is expecting the snd-usb-audio module */
		return 0;
	}

	printk(KERN_INFO "em28xx-audio.c: probing for em28x1 "
			 "non standard usbaudio\n");
	printk(KERN_INFO "em28xx-audio.c: Copyright (C) 2006 Markus "
			 "Rechberger\n");

	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
	if (!adev) {
		printk(KERN_ERR "em28xx-audio.c: out of memory\n");
		return -1;
	}
	card = snd_card_new(index[devnr], "Em28xx Audio", THIS_MODULE, 0);
	if (card == NULL) {
		kfree(adev);
		return -ENOMEM;
	}

	spin_lock_init(&adev->slock);
	ret = snd_pcm_new(card, "Em28xx Audio", 0, 0, 1, &pcm);
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_em28xx_pcm_capture);
	pcm->info_flags = 0;
	pcm->private_data = dev;
	strcpy(pcm->name, "Empia 28xx Capture");
	strcpy(card->driver, "Empia Em28xx Audio");
	strcpy(card->shortname, "Em28xx Audio");
	strcpy(card->longname, "Empia Em28xx Audio");

	err = snd_card_register(card);
	if (err < 0) {
		snd_card_free(card);
		return -ENOMEM;
	}
	adev->sndcard = card;
	adev->udev = dev->udev;
	dev->adev = adev;

	return 0;
}

static int em28xx_audio_fini(struct em28xx *dev)
{
	if (dev == NULL)
		return 0;

	if (dev->has_audio_class) {
		/* This device does not support the extension (in this case
		   the device is expecting the snd-usb-audio module */
		return 0;
	}

	if (dev->adev) {
		snd_card_free(dev->adev->sndcard);
		kfree(dev->adev);
		dev->adev = NULL;
	}

	return 0;
}

static struct em28xx_ops audio_ops = {
	.id   = EM28XX_AUDIO,
	.name = "Em28xx Audio Extension",
	.init = em28xx_audio_init,
	.fini = em28xx_audio_fini,
};

static int __init em28xx_alsa_register(void)
{
	return em28xx_register_extension(&audio_ops);
}

static void __exit em28xx_alsa_unregister(void)
{
	em28xx_unregister_extension(&audio_ops);
}

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Markus Rechberger <[e-mail]>");
MODULE_AUTHOR("Mauro Carvalho Chehab <[e-mail]>");
MODULE_DESCRIPTION("Em28xx Audio driver");

module_init(em28xx_alsa_register);
module_exit(em28xx_alsa_unregister);