ASoC: mxs-saif: fix clock prepare and enable unbalance issue

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.

Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Dong Aisheng 2012-07-20 17:20:24 +08:00 committed by Mark Brown
parent b8edf3e552
commit c2e1d9073f

View file

@ -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;