ASoC: davinci-mcasp: Calculate BCLK using TDM slots and remove channels rule

The McASP driver currently always sends as many slots or channels to a
i2s-wire as there are configured tdm_slots (see mcasp_i2s_hw_param()).
Thus the BLCK rate does not depend on the amount of channels, just the
configure amount of tdm-slots.

Reported-by: Misael Lopez Cruz <misael.lopez@ti.com>
Signed-off-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 12 insertions, 70 deletions

diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index bb4b78eada58..a01c6db6017b 100644
--- a/sound/soc/davinci/davinci-mcasp.c
+++ b/sound/soc/davinci/davinci-mcasp.c
@@ -915,15 +915,12 @@ static int davinci_mcasp_hw_params(struct snd_pcm_substream *substream,
          * the machine driver, we need to calculate the ratio.
          */
         if (mcasp->bclk_master && mcasp->bclk_div == 0 && mcasp->sysclk_freq) {
-                int channels = params_channels(params);
+                int slots = mcasp->tdm_slots;
                 int rate = params_rate(params);
                 int sbits = params_width(params);
                 int ppm, div;
 
-                if (channels > mcasp->tdm_slots)
-                        channels = mcasp->tdm_slots;
-
-                div = davinci_mcasp_calc_clk_div(mcasp, rate*sbits*channels,
+                div = davinci_mcasp_calc_clk_div(mcasp, rate*sbits*slots,
                                                  &ppm);
                 if (ppm)
                         dev_info(mcasp->dev, "Sample-rate is off by %d PPM\n",
@@ -1024,17 +1021,14 @@ static int davinci_mcasp_hw_rule_rate(struct snd_pcm_hw_params *params,
         struct snd_interval *ri =
                 hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
         int sbits = params_width(params);
-        int channels = params_channels(params);
+        int slots = rd->mcasp->tdm_slots;
         unsigned int list[ARRAY_SIZE(davinci_mcasp_dai_rates)];
         int i, count = 0;
 
-        if (channels > rd->mcasp->tdm_slots)
-                channels = rd->mcasp->tdm_slots;
-
         for (i = 0; i < ARRAY_SIZE(davinci_mcasp_dai_rates); i++) {
                 if (ri->min <= davinci_mcasp_dai_rates[i] &&
                     ri->max >= davinci_mcasp_dai_rates[i]) {
-                        uint bclk_freq = sbits*channels*
+                        uint bclk_freq = sbits*slots*
                                 davinci_mcasp_dai_rates[i];
                         int ppm;
 
@@ -1044,8 +1038,8 @@ static int davinci_mcasp_hw_rule_rate(struct snd_pcm_hw_params *params,
                 }
         }
         dev_dbg(rd->mcasp->dev,
-                "%d frequencies (%d-%d) for %d sbits and %d channels\n",
-                count, ri->min, ri->max, sbits, channels);
+                "%d frequencies (%d-%d) for %d sbits and %d tdm slots\n",
+                count, ri->min, ri->max, sbits, slots);
 
         return snd_interval_list(hw_param_interval(params, rule->var),
                                  count, list, 0);
@@ -1058,17 +1052,14 @@ static int davinci_mcasp_hw_rule_format(struct snd_pcm_hw_params *params,
         struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
         struct snd_mask nfmt;
         int rate = params_rate(params);
-        int channels = params_channels(params);
+        int slots = rd->mcasp->tdm_slots;
         int i, count = 0;
 
         snd_mask_none(&nfmt);
 
-        if (channels > rd->mcasp->tdm_slots)
-                channels = rd->mcasp->tdm_slots;
-
         for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
                 if (snd_mask_test(fmt, i)) {
-                        uint bclk_freq = snd_pcm_format_width(i)*channels*rate;
+                        uint bclk_freq = snd_pcm_format_width(i)*slots*rate;
                         int ppm;
 
                         davinci_mcasp_calc_clk_div(rd->mcasp, bclk_freq, &ppm);
@@ -1079,51 +1070,12 @@ static int davinci_mcasp_hw_rule_format(struct snd_pcm_hw_params *params,
                 }
         }
         dev_dbg(rd->mcasp->dev,
-                "%d possible sample format for %d Hz and %d channels\n",
-                count, rate, channels);
+                "%d possible sample format for %d Hz and %d tdm slots\n",
+                count, rate, slots);
 
         return snd_mask_refine(fmt, &nfmt);
 }
 
-static int davinci_mcasp_hw_rule_channels(struct snd_pcm_hw_params *params,
-                                          struct snd_pcm_hw_rule *rule)
-{
-        struct davinci_mcasp_ruledata *rd = rule->private;
-        struct snd_interval *ci =
-                hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
-        int sbits = params_width(params);
-        int rate = params_rate(params);
-        int max_chan_per_wire = rd->mcasp->tdm_slots < ci->max ?
-                rd->mcasp->tdm_slots : ci->max;
-        unsigned int list[ci->max - ci->min + 1];
-        int c1, c, count = 0;
-
-        for (c1 = ci->min; c1 <= max_chan_per_wire; c1++) {
-                uint bclk_freq = c1*sbits*rate;
-                int ppm;
-
-                davinci_mcasp_calc_clk_div(rd->mcasp, bclk_freq, &ppm);
-                if (abs(ppm) < DAVINCI_MAX_RATE_ERROR_PPM) {
-                        /* If we can use all tdm_slots, we can put any
-                           amount of channels to remaining wires as
-                           long as they fit in. */
-                        if (c1 == rd->mcasp->tdm_slots) {
-                                for (c = c1; c <= rd->serializers*c1 &&
-                                             c <= ci->max; c++)
-                                        list[count++] = c;
-                        } else {
-                                list[count++] = c1;
-                        }
-                }
-        }
-        dev_dbg(rd->mcasp->dev,
-                "%d possible channel counts (%d-%d) for %d Hz and %d sbits\n",
-                count, ci->min, ci->max, rate, sbits);
-
-        return snd_interval_list(hw_param_interval(params, rule->var),
-                                 count, list, 0);
-}
-
 static int davinci_mcasp_startup(struct snd_pcm_substream *substream,
                                  struct snd_soc_dai *cpu_dai)
 {
@@ -1180,24 +1132,14 @@ static int davinci_mcasp_startup(struct snd_pcm_substream *substream,
                                           SNDRV_PCM_HW_PARAM_RATE,
                                           davinci_mcasp_hw_rule_rate,
                                           ruledata,
-                                          SNDRV_PCM_HW_PARAM_FORMAT,
-                                          SNDRV_PCM_HW_PARAM_CHANNELS, -1);
+                                          SNDRV_PCM_HW_PARAM_FORMAT, -1);
                 if (ret)
                         return ret;
                 ret = snd_pcm_hw_rule_add(substream->runtime, 0,
                                           SNDRV_PCM_HW_PARAM_FORMAT,
                                           davinci_mcasp_hw_rule_format,
                                           ruledata,
-                                          SNDRV_PCM_HW_PARAM_RATE,
-                                          SNDRV_PCM_HW_PARAM_CHANNELS, -1);
-                if (ret)
-                        return ret;
-                ret = snd_pcm_hw_rule_add(substream->runtime, 0,
-                                          SNDRV_PCM_HW_PARAM_CHANNELS,
-                                          davinci_mcasp_hw_rule_channels,
-                                          ruledata,
-                                          SNDRV_PCM_HW_PARAM_RATE,
-                                          SNDRV_PCM_HW_PARAM_FORMAT, -1);
+                                          SNDRV_PCM_HW_PARAM_RATE, -1);
                 if (ret)
                         return ret;
         }