From 2219855aa7835e082ec134fafd9ddba84589d345 Mon Sep 17 00:00:00 2001 From: Andy Green Date: Wed, 2 Jul 2008 22:39:33 +0100 Subject: [PATCH] ASoC: Don't block system resume On OpenMoko soc-audio resume is taking 700ms of the whole resume time of 1.3s, dominated by writes to the codec over I2C. This patch shunts the resume guts into a workqueue which then is done asynchronously. The "card" is locked using the ALSA power state APIs as suggested by Mark Brown. [Added fix for race with resume to suspend and fixed a couple of nits from checkpatch -- broonie.] Signed-off-by: Andy Green Signed-off-by: Mark Brown --- include/sound/soc.h | 1 + sound/soc/soc-core.c | 52 ++++++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 47 insertions(+), 6 deletions(-) diff --git a/include/sound/soc.h b/include/sound/soc.h index aedb348..2d6c0eb 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -442,6 +442,7 @@ struct snd_soc_device { struct snd_soc_codec *codec; struct snd_soc_codec_device *codec_dev; struct delayed_work delayed_work; + struct work_struct deferred_resume_work; void *codec_data; }; diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 9e20333..e96930e 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -632,6 +632,16 @@ static int soc_suspend(struct platform_device *pdev, pm_message_t state) struct snd_soc_codec *codec = socdev->codec; int i; + /* Due to the resume being scheduled into a workqueue we could + * suspend before that's finished - wait for it to complete. + */ + snd_power_lock(codec->card); + snd_power_wait(codec->card, SNDRV_CTL_POWER_D0); + snd_power_unlock(codec->card); + + /* we're going to block userspace touching us until resume completes */ + snd_power_change_state(codec->card, SNDRV_CTL_POWER_D3hot); + /* mute any active DAC's */ for(i = 0; i < machine->num_links; i++) { struct snd_soc_codec_dai *dai = machine->dai_link[i].codec_dai; @@ -684,16 +694,27 @@ static int soc_suspend(struct platform_device *pdev, pm_message_t state) return 0; } -/* powers up audio subsystem after a suspend */ -static int soc_resume(struct platform_device *pdev) +/* deferred resume work, so resume can complete before we finished + * setting our codec back up, which can be very slow on I2C + */ +static void soc_resume_deferred(struct work_struct *work) { - struct snd_soc_device *socdev = platform_get_drvdata(pdev); - struct snd_soc_machine *machine = socdev->machine; - struct snd_soc_platform *platform = socdev->platform; - struct snd_soc_codec_device *codec_dev = socdev->codec_dev; + struct snd_soc_device *socdev = container_of(work, + struct snd_soc_device, + deferred_resume_work); + struct snd_soc_machine *machine = socdev->machine; + struct snd_soc_platform *platform = socdev->platform; + struct snd_soc_codec_device *codec_dev = socdev->codec_dev; struct snd_soc_codec *codec = socdev->codec; + struct platform_device *pdev = to_platform_device(socdev->dev); int i; + /* our power state is still SNDRV_CTL_POWER_D3hot from suspend time, + * so userspace apps are blocked from touching us + */ + + dev_info(socdev->dev, "starting resume work\n"); + if (machine->resume_pre) machine->resume_pre(pdev); @@ -735,6 +756,22 @@ static int soc_resume(struct platform_device *pdev) if (machine->resume_post) machine->resume_post(pdev); + dev_info(socdev->dev, "resume work completed\n"); + + /* userspace can access us now we are back as we were before */ + snd_power_change_state(codec->card, SNDRV_CTL_POWER_D0); +} + +/* powers up audio subsystem after a suspend */ +static int soc_resume(struct platform_device *pdev) +{ + struct snd_soc_device *socdev = platform_get_drvdata(pdev); + + dev_info(socdev->dev, "scheduling resume work\n"); + + if (!schedule_work(&socdev->deferred_resume_work)) + dev_err(socdev->dev, "work item may be lost\n"); + return 0; } @@ -781,6 +818,9 @@ static int soc_probe(struct platform_device *pdev) /* DAPM stream work */ INIT_DELAYED_WORK(&socdev->delayed_work, close_delayed_work); + /* deferred resume work */ + INIT_WORK(&socdev->deferred_resume_work, soc_resume_deferred); + return 0; platform_err: -- 1.5.6.5