ASoC: mxs-saif: fix clk_prepare() without matching clk_unprepare()

The clk_prepare() call in hw_params() has no matching clk_unprepare(),
leaving the clk with an ever-increasing prepare count.  Moreover,
hw_params() can be called multiple times which would again leave us
with a runaway prepare count.  Fix this by moving the clk_prepare()
call to the startup() function and adding a shutdown() function with
a matching clk_unprepare() as these operations are already correctly
bracketed by soc-core.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/mxs/mxs-saif.c b/sound/soc/mxs/mxs-saif.c
index c866ade28ad0a6a0005a9ec97e09c05bfa63a783..a6c7b8d87cd2f15198334840b9013980f87313c0 100644 (file)
--- a/sound/soc/mxs/mxs-saif.c
+++ b/sound/soc/mxs/mxs-saif.c
@@ -381,9 +381,19 @@ static int mxs_saif_startup(struct snd_pcm_substream *substream,
        __raw_writel(BM_SAIF_CTRL_CLKGATE,
                saif->base + SAIF_CTRL + MXS_CLR_ADDR);
 
+       clk_prepare(saif->clk);
+
        return 0;
 }
 
+static void mxs_saif_shutdown(struct snd_pcm_substream *substream,
+                             struct snd_soc_dai *cpu_dai)
+{
+       struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
+
+       clk_unprepare(saif->clk);
+}
+
 /*
  * Should only be called when port is inactive.
  * although can be called multiple times by upper layers.
@@ -424,8 +434,6 @@ static int mxs_saif_hw_params(struct snd_pcm_substream *substream,
                return ret;
        }
 
-       /* prepare clk in hw_param, enable in trigger */
-       clk_prepare(saif->clk);
        if (saif != master_saif) {
                /*
                * Set an initial clock rate for the saif internal logic to work
@@ -611,6 +619,7 @@ static int mxs_saif_trigger(struct snd_pcm_substream *substream, int cmd,
 
 static const struct snd_soc_dai_ops mxs_saif_dai_ops = {
        .startup = mxs_saif_startup,
+       .shutdown = mxs_saif_shutdown,
        .trigger = mxs_saif_trigger,
        .prepare = mxs_saif_prepare,
        .hw_params = mxs_saif_hw_params,