When I try to fix wm1811 standby issue for our customer, I find a strange behavior in ASOC core.

here is my test code:

snd_soc_dapm_disable_pin(&dapm,"MICBIAS2"); snd_soc_dapm_disable_pin(&dapm,"CLK_SYS"); snd_soc_dapm_sync(&dapm);

and add debug info in dapm_pre_sequence_async() and we will find these debug info printed:

d->bias_level = 1 d->target_bias_level = 0 in snd_soc_dapm_set_bias_level

from the debug log, when STANDBY -> OFF transition, it set bias_level to PREPARE.

that's wrong logic.

And more there is comment in source code: /* Prepare for a STADDBY->ON or ON->STANDBY transition */ But, the code isn't the same as the comment.

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From 58d8994bdc543909e9904b8df0787afc36684283 Mon Sep 17 00:00:00 2001

From: ning.a.zhang ning.a.zhang@intel.com Date: Fri, 10 May 2013 09:44:06 +0700 Subject: [PATCH] Asoc dapm behavior fix

in soc_dapm.c, there is a illogic behavior, when bias_level from STANDBY -> OFF transition. source does not follow its comment.

this patch is based on the comment

Signed-off-by: ning.a.zhang ning.a.zhang@intel.com --- sound/soc/soc-dapm.c | 14 ++++++++++++-- 1 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c index d6d9ba2..834ab4c 100644 --- a/sound/soc/soc-dapm.c +++ b/sound/soc/soc-dapm.c @@ -1486,8 +1486,9 @@ static void dapm_pre_sequence_async(void *data, async_cookie_t cookie) "ASoC: Failed to turn on bias: %d\n", ret); }

- /* Prepare for a STADDBY->ON or ON->STANDBY transition */ - if (d->bias_level != d->target_bias_level) { + /* If we're on and we're not supposed to be go into PREPARE */ + if (d->bias_level == SND_SOC_BIAS_ON && + d->target_bias_level != SND_SOC_BIAS_ON) { ret = snd_soc_dapm_set_bias_level(d, SND_SOC_BIAS_PREPARE); if (ret != 0) dev_err(d->dev, @@ -1525,6 +1526,15 @@ static void dapm_post_sequence_async(void *data, async_cookie_t cookie) pm_runtime_put(d->dev); }

+ if (d->bias_level == SND_SOC_BIAS_STANDBY && + (d->target_bias_level == SND_SOC_BIAS_PREPARE || + d->target_bias_level == SND_SOC_BIAS_ON)) { + ret = snd_soc_dapm_set_bias_level(d, SND_SOC_BIAS_PREPARE); + if (ret != 0) + dev_err(d->dev, "ASoC: Failed to apply prepare bias: %d\n", + ret); + } + /* If we just powered up then move to active bias */ if (d->bias_level == SND_SOC_BIAS_PREPARE && d->target_bias_level == SND_SOC_BIAS_ON) { -- 1.7.1