[ALSA] pcm: add snd_pcm_rate_to_rate_bit() helper

Add a snd_pcm_rate_to_rate_bit() function to factor out common code used
by several drivers.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

1 files changed, 8 insertions, 41 deletions

diff --git a/sound/soc/codecs/cs4270.c b/sound/soc/codecs/cs4270.c
index 8beae65d083c..43d50a4d8089 100644
--- a/sound/soc/codecs/cs4270.c
+++ b/sound/soc/codecs/cs4270.c
@@ -56,35 +56,6 @@ static unsigned int mclk_ratios[NUM_MCLK_RATIOS] =
         {64, 96, 128, 192, 256, 384, 512, 768, 1024};
 
 /*
- * Sampling rate <-> bit patter mapping
- *
- * This array maps sampling rates to their SNDRV_PCM_RATE_x equivalent.
- *
- * This is really something that ALSA should provide.
- *
- * This table is used by cs4270_set_dai_sysclk() to tell ALSA which sampling
- * rates the CS4270 currently supports.
- */
-static struct {
-        unsigned int rate;
-        unsigned int bit;
-} rate_map[] = {
-        {5512, SNDRV_PCM_RATE_5512},
-        {8000, SNDRV_PCM_RATE_8000},
-        {11025, SNDRV_PCM_RATE_11025},
-        {16000, SNDRV_PCM_RATE_16000},
-        {22050, SNDRV_PCM_RATE_22050},
-        {32000, SNDRV_PCM_RATE_32000},
-        {44100, SNDRV_PCM_RATE_44100},
-        {48000, SNDRV_PCM_RATE_48000},
-        {64000, SNDRV_PCM_RATE_64000},
-        {88200, SNDRV_PCM_RATE_88200},
-        {96000, SNDRV_PCM_RATE_96000},
-        {176400, SNDRV_PCM_RATE_176400},
-        {192000, SNDRV_PCM_RATE_192000}
-};
-
-/*
  * Determine the CS4270 samples rates.
  *
  * 'freq' is the input frequency to MCLK.  The other parameters are ignored.
@@ -126,19 +97,15 @@ static int cs4270_set_dai_sysclk(struct snd_soc_codec_dai *codec_dai,
         cs4270->mclk = freq;
 
         for (i = 0; i < NUM_MCLK_RATIOS; i++) {
-                unsigned int rate;
-                unsigned int j;
-                rate = freq / mclk_ratios[i];
-                for (j = 0; j < ARRAY_SIZE(rate_map); j++) {
-                        if (rate == rate_map[j].rate) {
-                                rates |= rate_map[j].bit;
-                                if (rate < rate_min)
-                                        rate_min = rate;
-                                if (rate > rate_max)
-                                        rate_max = rate;
-                        }
-                }
+                unsigned int rate = freq / mclk_ratios[i];
+                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) {
                 printk(KERN_ERR "cs4270: could not find a valid sample rate\n");