ASoC: davinci-mcasp: Allow best effort in selecting BCLK divider

Do not fail if the exact BLCK rate can not be produced, just print a
warning. Check that sysclk frequency is set before implicitly setting
the BCLK divider.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index 121971e..5b81adb 100644 (file)
--- a/sound/soc/davinci/davinci-mcasp.c
+++ b/sound/soc/davinci/davinci-mcasp.c
@@ -721,14 +721,18 @@ static int davinci_mcasp_hw_params(struct snd_pcm_substream *substream,
        int ret;
 
        /* If mcasp is BCLK master we need to set BCLK divider */
-       if (mcasp->bclk_master) {
+       if (mcasp->bclk_master && mcasp->sysclk_freq) {
                unsigned int bclk_freq = snd_soc_params_to_bclk(params);
+               unsigned int div = mcasp->sysclk_freq / bclk_freq;
                if (mcasp->sysclk_freq % bclk_freq != 0) {
-                       dev_err(mcasp->dev, "Can't produce required BCLK\n");
-                       return -EINVAL;
+                       if (((mcasp->sysclk_freq / div) - bclk_freq) >
+                           (bclk_freq - (mcasp->sysclk_freq / (div+1))))
+                               div++;
+                       dev_warn(mcasp->dev,
+                                "Inaccurate BCLK: %u Hz / %u != %u Hz\n",
+                                mcasp->sysclk_freq, div, bclk_freq);
                }
-               davinci_mcasp_set_clkdiv(
-                       cpu_dai, 1, mcasp->sysclk_freq / bclk_freq);
+               davinci_mcasp_set_clkdiv(cpu_dai, 1, div);
        }
 
        ret = mcasp_common_hw_param(mcasp, substream->stream,