ASoC: cs4270: allow passing freq=0 in set_dai_sysclk()

For setups with variable MCLKs, the current logic of limiting the
available sampling rates at startup time is not sufficient. We need to
be able to change the setting at a later point, and so the codec must
offer all possible rates until the hw_params are given.

This patches allows that by passing 0 as 'freq' argument to
cs4270_set_dai_sysclk().

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Daniel Mack 2010-01-15 17:36:48 +01:00 committed by Mark Brown
parent 738ada47cf
commit 6aababdf20

View file

@ -200,6 +200,11 @@ static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
* This function must be called by the machine driver's 'startup' function,
* otherwise the list of supported sample rates will not be available in
* time for ALSA.
*
* For setups with variable MCLKs, pass 0 as 'freq' argument. This will cause
* theoretically possible sample rates to be enabled. Call it again with a
* proper value set one the external clock is set (most probably you would do
* that from a machine's driver 'hw_param' hook.
*/
static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
int clk_id, unsigned int freq, int dir)
@ -213,20 +218,27 @@ static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
cs4270->mclk = freq;
for (i = 0; i < NUM_MCLK_RATIOS; i++) {
unsigned int rate = freq / cs4270_mode_ratios[i].ratio;
rates |= snd_pcm_rate_to_rate_bit(rate);
if (rate < rate_min)
rate_min = rate;
if (rate > rate_max)
rate_max = rate;
}
/* FIXME: soc should support a rate list */
rates &= ~SNDRV_PCM_RATE_KNOT;
if (cs4270->mclk) {
for (i = 0; i < NUM_MCLK_RATIOS; i++) {
unsigned int rate = freq / cs4270_mode_ratios[i].ratio;
rates |= snd_pcm_rate_to_rate_bit(rate);
if (rate < rate_min)
rate_min = rate;
if (rate > rate_max)
rate_max = rate;
}
/* FIXME: soc should support a rate list */
rates &= ~SNDRV_PCM_RATE_KNOT;
if (!rates) {
dev_err(codec->dev, "could not find a valid sample rate\n");
return -EINVAL;
if (!rates) {
dev_err(codec->dev, "could not find a valid sample rate\n");
return -EINVAL;
}
} else {
/* enable all possible rates */
rates = SNDRV_PCM_RATE_8000_192000;
rate_min = 8000;
rate_max = 192000;
}
codec_dai->playback.rates = rates;