[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>

8 files changed, 47 insertions, 145 deletions

diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index 2d5dee2fcb64..27f8ef48b5ec 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -925,6 +925,7 @@ snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
 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);
 
 static inline void snd_pcm_set_runtime_buffer(struct snd_pcm_substream *substream,
                                               struct snd_dma_buffer *bufp)
diff --git a/sound/core/pcm_misc.c b/sound/core/pcm_misc.c
index afd1e4929755..e5f25ae73ee2 100644
--- a/sound/core/pcm_misc.c
+++ b/sound/core/pcm_misc.c
@@ -450,3 +450,21 @@ int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
 }
 
 EXPORT_SYMBOL(snd_pcm_limit_hw_rates);
+
+/**
+ * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
+ * @rate: the sample rate to convert
+ *
+ * Returns the SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
+ * SNDRV_PCM_RATE_KNOT for an unknown rate.
+ */
+unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
+{
+        unsigned int i;
+
+        for (i = 0; i < snd_pcm_known_rates.count; i++)
+                if (snd_pcm_known_rates.list[i] == rate)
+                        return 1u << i;
+        return SNDRV_PCM_RATE_KNOT;
+}
+EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);
diff --git a/sound/pci/bt87x.c b/sound/pci/bt87x.c
index f0e12985dc29..85d50b64d2ba 100644
--- a/sound/pci/bt87x.c
+++ b/sound/pci/bt87x.c
@@ -340,28 +340,9 @@ static struct snd_pcm_hardware snd_bt87x_analog_hw = {
 
 static int snd_bt87x_set_digital_hw(struct snd_bt87x *chip, struct snd_pcm_runtime *runtime)
 {
-        static struct {
-                int rate;
-                unsigned int bit;
-        } ratebits[] = {
-                {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}
-        };
-        int i;
-
         chip->reg_control |= CTL_DA_IOM_DA;
         runtime->hw = snd_bt87x_digital_hw;
-        runtime->hw.rates = SNDRV_PCM_RATE_KNOT;
-        for (i = 0; i < ARRAY_SIZE(ratebits); ++i)
-                if (chip->dig_rate == ratebits[i].rate) {
-                        runtime->hw.rates = ratebits[i].bit;
-                        break;
-                }
+        runtime->hw.rates = snd_pcm_rate_to_rate_bit(chip->dig_rate);
         runtime->hw.rate_min = chip->dig_rate;
         runtime->hw.rate_max = chip->dig_rate;
         return 0;
diff --git a/sound/pci/rme32.c b/sound/pci/rme32.c
index ee0189b756d1..1475912588e9 100644
--- a/sound/pci/rme32.c
+++ b/sound/pci/rme32.c
@@ -258,19 +258,6 @@ static inline unsigned int snd_rme32_pcm_byteptr(struct rme32 * rme32)
                 & RME32_RCR_AUDIO_ADDR_MASK);
 }
 
-static int snd_rme32_ratecode(int rate)
-{
-        switch (rate) {
-        case 32000: return SNDRV_PCM_RATE_32000;
-        case 44100: return SNDRV_PCM_RATE_44100;
-        case 48000: return SNDRV_PCM_RATE_48000;
-        case 64000: return SNDRV_PCM_RATE_64000;
-        case 88200: return SNDRV_PCM_RATE_88200;
-        case 96000: return SNDRV_PCM_RATE_96000;
-        }
-        return 0;
-}
-
 /* silence callback for halfduplex mode */
 static int snd_rme32_playback_silence(struct snd_pcm_substream *substream, int channel, /* not used (interleaved data) */
                                       snd_pcm_uframes_t pos,
@@ -887,7 +874,7 @@ static int snd_rme32_playback_spdif_open(struct snd_pcm_substream *substream)
         if ((rme32->rcreg & RME32_RCR_KMODE) &&
             (rate = snd_rme32_capture_getrate(rme32, &dummy)) > 0) {
                 /* AutoSync */
-                runtime->hw.rates = snd_rme32_ratecode(rate);
+                runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
                 runtime->hw.rate_min = rate;
                 runtime->hw.rate_max = rate;
         }       
@@ -929,7 +916,7 @@ static int snd_rme32_capture_spdif_open(struct snd_pcm_substream *substream)
                 if (isadat) {
                         return -EIO;
                 }
-                runtime->hw.rates = snd_rme32_ratecode(rate);
+                runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
                 runtime->hw.rate_min = rate;
                 runtime->hw.rate_max = rate;
         }
@@ -965,7 +952,7 @@ snd_rme32_playback_adat_open(struct snd_pcm_substream *substream)
         if ((rme32->rcreg & RME32_RCR_KMODE) &&
             (rate = snd_rme32_capture_getrate(rme32, &dummy)) > 0) {
                 /* AutoSync */
-                runtime->hw.rates = snd_rme32_ratecode(rate);
+                runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
                 runtime->hw.rate_min = rate;
                 runtime->hw.rate_max = rate;
         }        
@@ -989,7 +976,7 @@ snd_rme32_capture_adat_open(struct snd_pcm_substream *substream)
                 if (!isadat) {
                         return -EIO;
                 }
-                runtime->hw.rates = snd_rme32_ratecode(rate);
+                runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
                 runtime->hw.rate_min = rate;
                 runtime->hw.rate_max = rate;
         }
diff --git a/sound/pci/rme96.c b/sound/pci/rme96.c
index ba4a34bae48f..0b3c532c4014 100644
--- a/sound/pci/rme96.c
+++ b/sound/pci/rme96.c
@@ -301,20 +301,6 @@ snd_rme96_capture_ptr(struct rme96 *rme96)
 }
 
 static int
-snd_rme96_ratecode(int rate)
-{
-    switch (rate) {
-    case 32000: return SNDRV_PCM_RATE_32000;
-    case 44100: return SNDRV_PCM_RATE_44100;
-    case 48000: return SNDRV_PCM_RATE_48000;
-    case 64000: return SNDRV_PCM_RATE_64000;
-    case 88200: return SNDRV_PCM_RATE_88200;
-    case 96000: return SNDRV_PCM_RATE_96000;
-    }
-    return 0;
-}
-
-static int
 snd_rme96_playback_silence(struct snd_pcm_substream *substream,
                            int channel, /* not used (interleaved data) */
                            snd_pcm_uframes_t pos,
@@ -1192,7 +1178,7 @@ snd_rme96_playback_spdif_open(struct snd_pcm_substream *substream)
             (rate = snd_rme96_capture_getrate(rme96, &dummy)) > 0)
         {
                 /* slave clock */
-                runtime->hw.rates = snd_rme96_ratecode(rate);
+                runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
                 runtime->hw.rate_min = rate;
                 runtime->hw.rate_max = rate;
         }        
@@ -1219,7 +1205,7 @@ snd_rme96_capture_spdif_open(struct snd_pcm_substream *substream)
                 if (isadat) {
                         return -EIO;
                 }
-                runtime->hw.rates = snd_rme96_ratecode(rate);
+                runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
                 runtime->hw.rate_min = rate;
                 runtime->hw.rate_max = rate;
         }
@@ -1259,7 +1245,7 @@ snd_rme96_playback_adat_open(struct snd_pcm_substream *substream)
             (rate = snd_rme96_capture_getrate(rme96, &dummy)) > 0)
         {
                 /* slave clock */
-                runtime->hw.rates = snd_rme96_ratecode(rate);
+                runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
                 runtime->hw.rate_min = rate;
                 runtime->hw.rate_max = rate;
         }        
@@ -1284,7 +1270,7 @@ snd_rme96_capture_adat_open(struct snd_pcm_substream *substream)
                 if (!isadat) {
                         return -EIO;
                 }
-                runtime->hw.rates = snd_rme96_ratecode(rate);
+                runtime->hw.rates = snd_pcm_rate_to_rate_bit(rate);
                 runtime->hw.rate_min = rate;
                 runtime->hw.rate_max = rate;
         }
diff --git a/sound/ppc/pmac.c b/sound/ppc/pmac.c
index 04b95ae5c3aa..4f9b19c90a43 100644
--- a/sound/ppc/pmac.c
+++ b/sound/ppc/pmac.c
@@ -490,35 +490,14 @@ static int snd_pmac_pcm_open(struct snd_pmac *chip, struct pmac_stream *rec,
                              struct snd_pcm_substream *subs)
 {
         struct snd_pcm_runtime *runtime = subs->runtime;
-        int i, j, fflags;
-        static int typical_freqs[] = {
-                44100,
-                22050,
-                11025,
-                0,
-        };
-        static int typical_freq_flags[] = {
-                SNDRV_PCM_RATE_44100,
-                SNDRV_PCM_RATE_22050,
-                SNDRV_PCM_RATE_11025,
-                0,
-        };
+        int i;
 
         /* look up frequency table and fill bit mask */
         runtime->hw.rates = 0;
-        fflags = chip->freqs_ok;
-        for (i = 0; typical_freqs[i]; i++) {
-                for (j = 0; j < chip->num_freqs; j++) {
-                        if ((chip->freqs_ok & (1 << j)) &&
-                            chip->freq_table[j] == typical_freqs[i]) {
-                                runtime->hw.rates |= typical_freq_flags[i];
-                                fflags &= ~(1 << j);
-                                break;
-                        }
-                }
-        }
-        if (fflags) /* rest */
-                runtime->hw.rates |= SNDRV_PCM_RATE_KNOT;
+        for (i = 0; i < chip->num_freqs; i++)
+                if (chip->freqs_ok & (1 << i))
+                        runtime->hw.rates |=
+                                snd_pcm_rate_to_rate_bit(chip->freq_table[i]);
 
         /* check for minimum and maximum rates */
         for (i = 0; i < chip->num_freqs; i++) {
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");
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;