The simple-card driver currently accepts a clock node in the cpu dai sub-node and only uses it as an alternative to the 'system-clock-frequency' property to get the current frequency.
This patch adds another use of the passed clock node. If mclk-fs is specified, the clocks in cpu and codec dai sub-nodes will be set to the calculated rate (stream rate * mclk_fs) in hw_params.
This allows platforms to pass tuneable clocks as phandle that will automatically be set to the right rates.
Signed-off-by: Daniel Mack daniel@zonque.org ---
This is the only patch that's left from the series of three that I posted earlier.
v1 → v2:
* Apply the setting to both the codec and the cpu dai * Check for errors from clk_set_rate() and avoid unnecessary rate changes.
.../devicetree/bindings/sound/simple-card.txt | 5 +++++ sound/soc/generic/simple-card.c | 21 +++++++++++++++++++++ 2 files changed, 26 insertions(+)
diff --git a/Documentation/devicetree/bindings/sound/simple-card.txt b/Documentation/devicetree/bindings/sound/simple-card.txt index 17c13e74667d..a4c72d09cd45 100644 --- a/Documentation/devicetree/bindings/sound/simple-card.txt +++ b/Documentation/devicetree/bindings/sound/simple-card.txt @@ -86,6 +86,11 @@ Optional CPU/CODEC subnodes properties: in dai startup() and disabled with clk_disable_unprepare() in dai shutdown(). + If a clock is specified and a + multiplication factor is given with + mclk-fs, the clock will be set to the + calculated mclk frequency when the + stream starts. - system-clock-direction-out : specifies clock direction as 'out' on initialization. It is useful for some aCPUs with fixed clocks. diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c index 6959a74a6f49..4a516c428b3d 100644 --- a/sound/soc/generic/simple-card.c +++ b/sound/soc/generic/simple-card.c @@ -135,6 +135,18 @@ static void asoc_simple_card_shutdown(struct snd_pcm_substream *substream) asoc_simple_card_clk_disable(&dai_props->codec_dai); }
+static int asoc_simple_set_clk_rate(struct asoc_simple_dai *simple_dai, + unsigned long rate) +{ + if (!simple_dai->clk) + return 0; + + if (clk_get_rate(simple_dai->clk) == rate) + return 0; + + return clk_set_rate(simple_dai->clk, rate); +} + static int asoc_simple_card_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params) { @@ -154,6 +166,15 @@ static int asoc_simple_card_hw_params(struct snd_pcm_substream *substream,
if (mclk_fs) { mclk = params_rate(params) * mclk_fs; + + ret = asoc_simple_set_clk_rate(&dai_props->codec_dai, mclk); + if (ret < 0) + return ret; + + ret = asoc_simple_set_clk_rate(&dai_props->cpu_dai, mclk); + if (ret < 0) + return ret; + ret = snd_soc_dai_set_sysclk(codec_dai, 0, mclk, SND_SOC_CLOCK_IN); if (ret && ret != -ENOTSUPP)