From 3994e0b139c709047cdeb44b6c28cfb39f89f3f2 Mon Sep 17 00:00:00 2001 From: Vaibhav Agarwal Date: Thu, 28 Jan 2016 21:15:40 +0530 Subject: greybus: audio: use variable 'is_connected' to maintain module state there is race condition between _disconnect() request & stop_trigger() in case of abrupt module removal. And sometimes this can lead to deadlock while acquiring codec_info->lock. To avoid such situation, atomic variable is used to maintain codec connected state. During dai operations (trigger, shutdown, etc.), 'is_connected' variable is validated to avoid unnecessary lock acquire in case module already removed. Signed-off-by: Vaibhav Agarwal Signed-off-by: Greg Kroah-Hartman --- drivers/staging/greybus/audio_codec.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'drivers/staging/greybus/audio_codec.h') diff --git a/drivers/staging/greybus/audio_codec.h b/drivers/staging/greybus/audio_codec.h index 56110913b70e..4c19bd884488 100644 --- a/drivers/staging/greybus/audio_codec.h +++ b/drivers/staging/greybus/audio_codec.h @@ -108,6 +108,15 @@ struct gbaudio_codec_info { int manager_id; char name[NAME_SIZE]; + /* + * there can be a rece condition between gb_audio_disconnect() + * and dai->trigger from above ASoC layer. + * To avoid any deadlock over codec_info->lock, atomic variable + * is used. + */ + atomic_t is_connected; + struct mutex lock; + /* soc related data */ struct snd_soc_codec *codec; struct device *dev; @@ -139,7 +148,6 @@ struct gbaudio_codec_info { struct list_head widget_list; struct list_head codec_ctl_list; struct list_head widget_ctl_list; - struct mutex lock; }; struct gbaudio_dai *gbaudio_find_dai(struct gbaudio_codec_info *gbcodec, -- cgit v1.2.3