ALSA: pcm: add a helper function to apply parameter rules

Application of rules to parameters of PCM substream is done in a call of
snd_pcm_hw_refine(), while the function includes much codes and is not
enough friendly to readers.

This commit splits the codes to a separated function so that readers can
get it easily. I leave desicion into compilers to merge the function into
its callee.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 7e811ace6bf2ad848d249aafe97e48f1a414a293..000e6e9a0c2b0071c1b60d37380e67466801bf47 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -319,43 +319,23 @@ static int constrain_interval_params(struct snd_pcm_substream *substream,
        return 0;
 }
 
-int snd_pcm_hw_refine(struct snd_pcm_substream *substream, 
-                     struct snd_pcm_hw_params *params)
+static int constrain_params_by_rules(struct snd_pcm_substream *substream,
+                                    struct snd_pcm_hw_params *params)
 {
+       struct snd_pcm_hw_constraints *constrs =
+                                       &substream->runtime->hw_constraints;
        unsigned int k;
-       struct snd_pcm_hardware *hw;
-       struct snd_interval *i = NULL;
-       struct snd_mask *m = NULL;
-       struct snd_pcm_hw_constraints *constrs = &substream->runtime->hw_constraints;
        unsigned int rstamps[constrs->rules_num];
        unsigned int vstamps[SNDRV_PCM_HW_PARAM_LAST_INTERVAL + 1];
        unsigned int stamp = 2;
-       int changed, again;
-       int err;
-
-       struct snd_mask __maybe_unused old_mask;
-       struct snd_interval __maybe_unused old_interval;
-
-       params->info = 0;
-       params->fifo_size = 0;
-       if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_SAMPLE_BITS))
-               params->msbits = 0;
-       if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_RATE)) {
-               params->rate_num = 0;
-               params->rate_den = 0;
-       }
-
-       err = constrain_mask_params(substream, params);
-       if (err < 0)
-               return err;
-
-       err = constrain_interval_params(substream, params);
-       if (err < 0)
-               return err;
+       struct snd_mask old_mask;
+       struct snd_interval old_interval;
+       int again;
+       int changed;
 
        for (k = 0; k < constrs->rules_num; k++)
                rstamps[k] = 0;
-       for (k = 0; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++) 
+       for (k = 0; k <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; k++)
                vstamps[k] = (params->rmask & (1 << k)) ? 1 : 0;
        do {
                again = 0;
@@ -405,6 +385,39 @@ int snd_pcm_hw_refine(struct snd_pcm_substream *substream,
                        stamp++;
                }
        } while (again);
+
+       return 0;
+}
+
+int snd_pcm_hw_refine(struct snd_pcm_substream *substream,
+                     struct snd_pcm_hw_params *params)
+{
+       struct snd_pcm_hardware *hw;
+       struct snd_interval *i = NULL;
+       struct snd_mask *m = NULL;
+       int err;
+
+       params->info = 0;
+       params->fifo_size = 0;
+       if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_SAMPLE_BITS))
+               params->msbits = 0;
+       if (params->rmask & (1 << SNDRV_PCM_HW_PARAM_RATE)) {
+               params->rate_num = 0;
+               params->rate_den = 0;
+       }
+
+       err = constrain_mask_params(substream, params);
+       if (err < 0)
+               return err;
+
+       err = constrain_interval_params(substream, params);
+       if (err < 0)
+               return err;
+
+       err = constrain_params_by_rules(substream, params);
+       if (err < 0)
+               return err;
+
        if (!params->msbits) {
                i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
                if (snd_interval_single(i))
@@ -432,10 +445,10 @@ int snd_pcm_hw_refine(struct snd_pcm_substream *substream,
                i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
                if (snd_mask_min(m) == snd_mask_max(m) &&
                     snd_interval_min(i) == snd_interval_max(i)) {
-                       changed = substream->ops->ioctl(substream,
+                       err = substream->ops->ioctl(substream,
                                        SNDRV_PCM_IOCTL1_FIFO_SIZE, params);
-                       if (changed < 0)
-                               return changed;
+                       if (err < 0)
+                               return err;
                }
        }
        params->rmask = 0;