Dong Aisheng b29396@freescale.com writes:
From: Dong Aisheng dong.aisheng@linaro.org
Currently we directly call a clock_enable in trigger function without a clk_prepare as pair first. This will cause system hang immediately when run capture because the clock was not prepared(playback does not hang because the clock was prepared already by get_mclk before), a warning message in clock framework may cause a deadlock to reclaim clock lock (see: pl011_console_write).
Here we prepare clock first in hw_param, then enable it in trigger function to guarantee the balance.
Cc: Mark Brown broonie@opensource.wolfsonmicro.com Cc: Liam Girdwood lrg@ti.com Cc: Wolfram Sang w.sang@pengutronix.de Cc: Shawn Guo shawn.guo@linaro.org Signed-off-by: Dong Aisheng dong.aisheng@linaro.org
sound/soc/mxs/mxs-saif.c | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/sound/soc/mxs/mxs-saif.c b/sound/soc/mxs/mxs-saif.c index aba71bf..fdbb36a 100644 --- a/sound/soc/mxs/mxs-saif.c +++ b/sound/soc/mxs/mxs-saif.c @@ -394,9 +394,14 @@ static int mxs_saif_hw_params(struct snd_pcm_substream *substream, struct snd_soc_dai *cpu_dai) { struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
struct mxs_saif *master_saif; u32 scr, stat; int ret;
master_saif = mxs_saif_get_master(saif);
if (!master_saif)
return -EINVAL;/* mclk should already be set */ if (!saif->mclk && saif->mclk_in_use) { dev_err(cpu_dai->dev, "set mclk first\n");
@@ -420,6 +425,11 @@ 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)
clk_prepare(master_saif->clk);scr = __raw_readl(saif->base + SAIF_CTRL);
scr &= ~BM_SAIF_CTRL_WORD_LENGTH;
--
This is missing a matching clk_unprepare() call.