From f9911803e82a32c126c40dd6246ade2faf472cbc Mon Sep 17 00:00:00 2001 From: Jyri Sarha Date: Tue, 13 Jan 2015 21:16:34 +0200 Subject: [PATCH] ASoC: simple-card: Enable and disable DAI clocks as needed Call clk_prepare_enable() and clk_disable_unprepare() for cpu dai clock and codec dai clock in dai statup and shutdown callbacks. This to make sure the related clock are enabled when the audio device is used. Signed-off-by: Jyri Sarha Signed-off-by: Mark Brown --- .../devicetree/bindings/sound/simple-card.txt | 5 +++ include/sound/simple_card.h | 1 + sound/soc/generic/simple-card.c | 34 +++++++++++++++++++ 3 files changed, 40 insertions(+) diff --git a/Documentation/devicetree/bindings/sound/simple-card.txt b/Documentation/devicetree/bindings/sound/simple-card.txt index c3cba600bf11..73bf314f7240 100644 --- a/Documentation/devicetree/bindings/sound/simple-card.txt +++ b/Documentation/devicetree/bindings/sound/simple-card.txt @@ -75,6 +75,11 @@ Optional CPU/CODEC subnodes properties: it can be specified via "clocks" if system has clock node (= common clock), or "system-clock-frequency" (if system doens't support common clock) + If a clock is specified, it is + enabled with clk_prepare_enable() + in dai startup() and disabled with + clk_disable_unprepare() in dai + shutdown(). Example 1 - single DAI link: diff --git a/include/sound/simple_card.h b/include/sound/simple_card.h index 9b0ac77177b6..1255ddb1d3e2 100644 --- a/include/sound/simple_card.h +++ b/include/sound/simple_card.h @@ -20,6 +20,7 @@ struct asoc_simple_dai { unsigned int sysclk; int slots; int slot_width; + struct clk *clk; }; struct asoc_simple_card_info { diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c index fb9240fdc9b7..cb3998d96cca 100644 --- a/sound/soc/generic/simple-card.c +++ b/sound/soc/generic/simple-card.c @@ -39,6 +39,37 @@ struct simple_card_data { #define simple_priv_to_link(priv, i) ((priv)->snd_card.dai_link + i) #define simple_priv_to_props(priv, i) ((priv)->dai_props + i) +static int asoc_simple_card_startup(struct snd_pcm_substream *substream) +{ + struct snd_soc_pcm_runtime *rtd = substream->private_data; + struct simple_card_data *priv = snd_soc_card_get_drvdata(rtd->card); + struct simple_dai_props *dai_props = + &priv->dai_props[rtd - rtd->card->rtd]; + int ret; + + ret = clk_prepare_enable(dai_props->cpu_dai.clk); + if (ret) + return ret; + + ret = clk_prepare_enable(dai_props->codec_dai.clk); + if (ret) + clk_disable_unprepare(dai_props->cpu_dai.clk); + + return ret; +} + +static void asoc_simple_card_shutdown(struct snd_pcm_substream *substream) +{ + struct snd_soc_pcm_runtime *rtd = substream->private_data; + struct simple_card_data *priv = snd_soc_card_get_drvdata(rtd->card); + struct simple_dai_props *dai_props = + &priv->dai_props[rtd - rtd->card->rtd]; + + clk_disable_unprepare(dai_props->cpu_dai.clk); + + clk_disable_unprepare(dai_props->codec_dai.clk); +} + static int asoc_simple_card_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params) { @@ -58,6 +89,8 @@ static int asoc_simple_card_hw_params(struct snd_pcm_substream *substream, } static struct snd_soc_ops asoc_simple_card_ops = { + .startup = asoc_simple_card_startup, + .shutdown = asoc_simple_card_shutdown, .hw_params = asoc_simple_card_hw_params, }; @@ -219,6 +252,7 @@ asoc_simple_card_sub_parse_of(struct device_node *np, } dai->sysclk = clk_get_rate(clk); + dai->clk = clk; } else if (!of_property_read_u32(np, "system-clock-frequency", &val)) { dai->sysclk = val; } else { -- 2.20.1