[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, 6 insertions, 23 deletions

diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c
index ac5666f4c6d5..cbe8b335147c 100644
--- a/sound/usb/usbaudio.c
+++ b/sound/usb/usbaudio.c
@@ -123,7 +123,6 @@ struct audioformat {
         unsigned int rate_min, rate_max;        /* min/max rates */
         unsigned int nr_rates;          /* number of rate table entries */
         unsigned int *rate_table;       /* rate table */
-        unsigned int needs_knot;        /* any unusual rates? */
 };
 
 struct snd_usb_substream;
@@ -1761,7 +1760,7 @@ static int check_hw_params_convention(struct snd_usb_substream *subs)
                 channels[f->format] |= (1 << f->channels);
                 rates[f->format] |= f->rates;
                 /* needs knot? */
-                if (f->needs_knot)
+                if (f->rates & SNDRV_PCM_RATE_KNOT)
                         goto __out;
         }
         /* check whether channels and rates match for all formats */
@@ -1817,7 +1816,7 @@ static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
                 if (fp->rates & SNDRV_PCM_RATE_CONTINUOUS)
                         return 0;
                 count += fp->nr_rates;
-                if (fp->needs_knot)
+                if (fp->rates & SNDRV_PCM_RATE_KNOT)
                         needs_knot = 1;
         }
         if (!needs_knot)
@@ -2453,7 +2452,7 @@ static int parse_audio_format_rates(struct snd_usb_audio *chip, struct audioform
                                     unsigned char *fmt, int offset)
 {
         int nr_rates = fmt[offset];
-        int found;
+
         if (fmt[0] < offset + 1 + 3 * (nr_rates ? nr_rates : 2)) {
                 snd_printk(KERN_ERR "%d:%u:%d : invalid FORMAT_TYPE desc\n",
                                    chip->dev->devnum, fp->iface, fp->altsetting);
@@ -2464,20 +2463,15 @@ static int parse_audio_format_rates(struct snd_usb_audio *chip, struct audioform
                 /*
                  * build the rate table and bitmap flags
                  */
-                int r, idx, c;
+                int r, idx;
                 unsigned int nonzero_rates = 0;
-                /* this table corresponds to the SNDRV_PCM_RATE_XXX bit */
-                static unsigned int conv_rates[] = {
-                        5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
-                        64000, 88200, 96000, 176400, 192000
-                };
+
                 fp->rate_table = kmalloc(sizeof(int) * nr_rates, GFP_KERNEL);
                 if (fp->rate_table == NULL) {
                         snd_printk(KERN_ERR "cannot malloc\n");
                         return -1;
                 }
 
-                fp->needs_knot = 0;
                 fp->nr_rates = nr_rates;
                 fp->rate_min = fp->rate_max = combine_triple(&fmt[8]);
                 for (r = 0, idx = offset + 1; r < nr_rates; r++, idx += 3) {
@@ -2493,23 +2487,12 @@ static int parse_audio_format_rates(struct snd_usb_audio *chip, struct audioform
                                 fp->rate_min = rate;
                         else if (rate > fp->rate_max)
                                 fp->rate_max = rate;
-                        found = 0;
-                        for (c = 0; c < (int)ARRAY_SIZE(conv_rates); c++) {
-                                if (rate == conv_rates[c]) {
-                                        found = 1;
-                                        fp->rates |= (1 << c);
-                                        break;
-                                }
-                        }
-                        if (!found)
-                                fp->needs_knot = 1;
+                        fp->rates |= snd_pcm_rate_to_rate_bit(rate);
                 }
                 if (!nonzero_rates) {
                         hwc_debug("All rates were zero. Skipping format!\n");
                         return -1;
                 }
-                if (fp->needs_knot)
-                        fp->rates |= SNDRV_PCM_RATE_KNOT;
         } else {
                 /* continuous rates */
                 fp->rates = SNDRV_PCM_RATE_CONTINUOUS;