[alsa-devel] [PATCH] ASoC: AM3517: Fix AIC23 suspend/resume hang

[Mark Brown]

On Thu, Nov 26, 2009 at 08:31:11AM +0530, Aggarwal, Anuj wrote:

> I have already tried that but it doesn't fix the problem entirely.
> Still, I was not able to playback properly because the bias settings
> were not handled correctly and as you can see, it writes to some 
> invalid registers too (all registers don't exist between 0 and ARRAY_SIZE).

Please also note the following patch which is queued for 2.6.32:

commit 50b6bce59d154b5db137907a5c0ed45a4e7a3829
Author: Mark Brown <broonie at opensource.wolfsonmicro.com>
Date:   Mon Nov 23 13:11:53 2009 +0000

    ASoC: Fix suspend with active audio streams
    
    When we get a stream suspend event force the power down since otherwise
    the stream would remain marked as active.  In future we'll probably want
    to make this stream-specific and add an interface to make the power down
    of other widgets optional in order to support leaving bypass paths
    active while suspending the processor.
    
    Cc: stable at kernel.org
    Reported-by: Joonyoung Shim <jy0922.shim at samsung.com>
    Tested-by: Joonyoung Shim <jy0922.shim at samsung.com>
    Acked-by: Liam Girdwood <lrg at slimlogic.co.uk>
    Signed-off-by: Mark Brown <broonie at opensource.wolfsonmicro.com>

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index d89f6dc..66d4c16 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -973,9 +973,19 @@ static int dapm_power_widgets(struct snd_soc_codec *codec, int event)
 			if (!w->power_check)
 				continue;
 
-			power = w->power_check(w);
-			if (power)
-				sys_power = 1;
+			/* If we're suspending then pull down all the 
+			 * power. */
+			switch (event) {
+			case SND_SOC_DAPM_STREAM_SUSPEND:
+				power = 0;
+				break;
+
+			default:
+				power = w->power_check(w);
+				if (power)
+					sys_power = 1;
+				break;
+			}
 
 			if (w->power == power)
 				continue;
@@ -999,8 +1009,12 @@ static int dapm_power_widgets(struct snd_soc_codec *codec, int event)
 		case SND_SOC_DAPM_STREAM_RESUME:
 			sys_power = 1;
 			break;
+		case SND_SOC_DAPM_STREAM_SUSPEND:
+			sys_power = 0;
+			break;
 		case SND_SOC_DAPM_STREAM_NOP:
 			sys_power = codec->bias_level != SND_SOC_BIAS_STANDBY;
+			break;
 		default:
 			break;
 		}