From mboxrd@z Thu Jan 1 00:00:00 1970 From: mpa@pengutronix.de (Markus Pargmann) Date: Fri, 11 Oct 2013 12:11:02 +0200 Subject: [PATCH 1/3] ASoC: snd_soc_dai_ops trigger function description In-Reply-To: <1381486264-1672-1-git-send-email-mpa@pengutronix.de> References: <1381486264-1672-1-git-send-email-mpa@pengutronix.de> Message-ID: <1381486264-1672-2-git-send-email-mpa@pengutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Add a comment to the trigger function in snd_soc_dai_ops struct about possible command sequences. Signed-off-by: Markus Pargmann --- include/sound/soc-dai.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/include/sound/soc-dai.h b/include/sound/soc-dai.h index ae9a227..0f2e5da 100644 --- a/include/sound/soc-dai.h +++ b/include/sound/soc-dai.h @@ -166,6 +166,13 @@ struct snd_soc_dai_ops { struct snd_soc_dai *); int (*prepare)(struct snd_pcm_substream *, struct snd_soc_dai *); + /* + * NOTE: Commands passed to the trigger function are not necessarily + * compatible with the current state of the dai. For example this + * sequence of commands is possible: START STOP STOP. + * So do not unconditionally use refcounting functions in the trigger + * function, e.g. clk_enable/disable. + */ int (*trigger)(struct snd_pcm_substream *, int, struct snd_soc_dai *); int (*bespoke_trigger)(struct snd_pcm_substream *, int, -- 1.8.4.rc3