From e3a9269f874067fcefc5eb8037466161fb0fe3f4 Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Sat, 11 Jan 2014 10:24:43 +0100 Subject: ALSA: Add helper function for intersecting two rate masks A bit of special care is necessary when creating the intersection of two rate masks. This comes from the special meaning of the SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT bits, which needs special handling when intersecting two rate masks. SNDRV_PCM_RATE_CONTINUOUS means the hardware supports all rates in a specific interval. SNDRV_PCM_RATE_KNOT means the hardware supports a set of discrete rates specified by a list constraint. For all other cases the supported rates are specified directly in the rate mask. Signed-off-by: Lars-Peter Clausen Reviewed-by: Takashi Iwai Signed-off-by: Mark Brown --- include/sound/pcm.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/sound/pcm.h') diff --git a/include/sound/pcm.h b/include/sound/pcm.h index 84b10f9a2832..d0170913374d 100644 --- a/include/sound/pcm.h +++ b/include/sound/pcm.h @@ -901,6 +901,8 @@ extern const struct snd_pcm_hw_constraint_list snd_pcm_known_rates; int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime); unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate); unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit); +unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a, + unsigned int rates_b); static inline void snd_pcm_set_runtime_buffer(struct snd_pcm_substream *substream, struct snd_dma_buffer *bufp) -- cgit v1.2.3