Commit e831d80b authored by Russell King's avatar Russell King
Browse files

ALSA: AACI: fix number of channels for record 



AC'97 codecs only support two channels for recording, so we shouldn't
advertize that there are up to six channels available.  Limit the
selection of 4 and 6 channel audio to playback only.

As this adds additional SNDRV_PCM_STREAM_PLAYBACK conditionals, we can
combine some resulting in the elimination of __aaci_pcm_open() entirely,
and making the code easier to read.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent b60fb519

sound/arm/aaci.c

+52 −62
Original line number Diff line number Diff line
@@ -357,7 +357,7 @@ static struct snd_pcm_hardware aaci_hw_info = { 


	/* rates are setup from the AC'97 codec */

	.channels_min		= 2,

	.channels_max		= 6,

	.channels_max		= 2,

	.buffer_bytes_max	= 64 * 1024,

	.period_bytes_min	= 256,

	.period_bytes_max	= PAGE_SIZE,
@@ -365,22 +365,67 @@ static struct snd_pcm_hardware aaci_hw_info = { 
	.periods_max		= PAGE_SIZE / 16,

};



static int __aaci_pcm_open(struct aaci *aaci,

			   struct snd_pcm_substream *substream,

			   struct aaci_runtime *aacirun)

/*

 * We can support two and four channel audio.  Unfortunately

 * six channel audio requires a non-standard channel ordering:

 *   2 -> FL(3), FR(4)

 *   4 -> FL(3), FR(4), SL(7), SR(8)

 *   6 -> FL(3), FR(4), SL(7), SR(8), C(6), LFE(9) (required)

 *        FL(3), FR(4), C(6), SL(7), SR(8), LFE(9) (actual)

 * This requires an ALSA configuration file to correct.

 */

static int aaci_rule_channels(struct snd_pcm_hw_params *p,

	struct snd_pcm_hw_rule *rule)

{

	static unsigned int channel_list[] = { 2, 4, 6 };

	struct aaci *aaci = rule->private;

	unsigned int mask = 1 << 0, slots;



	/* pcms[0] is the our 5.1 PCM instance. */

	slots = aaci->ac97_bus->pcms[0].r[0].slots;

	if (slots & (1 << AC97_SLOT_PCM_SLEFT)) {

		mask |= 1 << 1;

		if (slots & (1 << AC97_SLOT_LFE))

			mask |= 1 << 2;

	}



	return snd_interval_list(hw_param_interval(p, rule->var),

				 ARRAY_SIZE(channel_list), channel_list, mask);

}



static int aaci_pcm_open(struct snd_pcm_substream *substream)

{

	struct snd_pcm_runtime *runtime = substream->runtime;

	struct aaci *aaci = substream->private_data;

	struct aaci_runtime *aacirun;

	int ret = 0;



	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {

		aacirun = &aaci->playback;

	} else {

		aacirun = &aaci->capture;

	}



	aacirun->substream = substream;

	runtime->private_data = aacirun;

	runtime->hw = aaci_hw_info;

	runtime->hw.rates = aacirun->pcm->rates;

	snd_pcm_limit_hw_rates(runtime);



	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&

	    aacirun->pcm->r[1].slots)

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {

		runtime->hw.channels_max = 6;



		/* Add rule describing channel dependency. */

		ret = snd_pcm_hw_rule_add(substream->runtime, 0,

					  SNDRV_PCM_HW_PARAM_CHANNELS,

					  aaci_rule_channels, aaci,

					  SNDRV_PCM_HW_PARAM_CHANNELS, -1);

		if (ret)

			return ret;



		if (aacirun->pcm->r[1].slots)

			snd_ac97_pcm_double_rate_rules(runtime);

	}



	/*

	 * FIXME: ALSA specifies fifo_size in bytes.  If we're in normal
@@ -512,61 +557,6 @@ static const u32 channels_to_txmask[] = { 
	[6] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8 | CR_SL6 | CR_SL9,

};



/*

 * We can support two and four channel audio.  Unfortunately

 * six channel audio requires a non-standard channel ordering:

 *   2 -> FL(3), FR(4)

 *   4 -> FL(3), FR(4), SL(7), SR(8)

 *   6 -> FL(3), FR(4), SL(7), SR(8), C(6), LFE(9) (required)

 *        FL(3), FR(4), C(6), SL(7), SR(8), LFE(9) (actual)

 * This requires an ALSA configuration file to correct.

 */

static unsigned int channel_list[] = { 2, 4, 6 };



static int

aaci_rule_channels(struct snd_pcm_hw_params *p, struct snd_pcm_hw_rule *rule)

{

	struct aaci *aaci = rule->private;

	unsigned int chan_mask = 1 << 0, slots;



	/*

	 * pcms[0] is the our 5.1 PCM instance.

	 */

	slots = aaci->ac97_bus->pcms[0].r[0].slots;

	if (slots & (1 << AC97_SLOT_PCM_SLEFT)) {

		chan_mask |= 1 << 1;

		if (slots & (1 << AC97_SLOT_LFE))

			chan_mask |= 1 << 2;

	}



	return snd_interval_list(hw_param_interval(p, rule->var),

				 ARRAY_SIZE(channel_list), channel_list,

				 chan_mask);

}



static int aaci_pcm_open(struct snd_pcm_substream *substream)

{

	struct aaci *aaci = substream->private_data;

	int ret;



	/*

	 * Add rule describing channel dependency.

	 */

	ret = snd_pcm_hw_rule_add(substream->runtime, 0,

				  SNDRV_PCM_HW_PARAM_CHANNELS,

				  aaci_rule_channels, aaci,

				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);

	if (ret)

		return ret;



	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {

		ret = __aaci_pcm_open(aaci, substream, &aaci->playback);

	} else {

		ret = __aaci_pcm_open(aaci, substream, &aaci->capture);

	}

	return ret;

}



static int aaci_pcm_playback_hw_params(struct snd_pcm_substream *substream,

				       struct snd_pcm_hw_params *params)

{

CRA Git | Maintained and supported by SUSTech CRA and CCSE