summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorDaniel Mack <daniel@zonque.org>2018-07-02 17:11:00 +0200
committerMark Brown <broonie@kernel.org>2018-07-05 11:08:08 +0100
commit90eb6b59d311e6facd040124cb5b659a865125b8 (patch)
treeedd6856bdfffc011e3365f0d9e12c2a4e089eab2
parent74b37e299f038c910dc728d736e3f071ba0ead2a (diff)
downloadlinux-90eb6b59d311e6facd040124cb5b659a865125b8.tar.bz2
ASoC: pxa-ssp: add support for an external clock in devicetree
Allow setting a clock called 'extclk' in the device of the ssp-dai device. If specified, this clock will be set to the mclk rate from the DAI's .set_sysclk() callback. The DAI will also configure itself to use that external clock. Signed-off-by: Daniel Mack <daniel@zonque.org> Signed-off-by: Mark Brown <broonie@kernel.org>
-rw-r--r--Documentation/devicetree/bindings/sound/mrvl,pxa-ssp.txt8
-rw-r--r--sound/soc/pxa/pxa-ssp.c25
2 files changed, 33 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/sound/mrvl,pxa-ssp.txt b/Documentation/devicetree/bindings/sound/mrvl,pxa-ssp.txt
index 74c9ba6c2823..93b982e9419f 100644
--- a/Documentation/devicetree/bindings/sound/mrvl,pxa-ssp.txt
+++ b/Documentation/devicetree/bindings/sound/mrvl,pxa-ssp.txt
@@ -5,6 +5,14 @@ Required properties:
compatible Must be "mrvl,pxa-ssp-dai"
port A phandle reference to a PXA ssp upstream device
+Optional properties:
+
+ clock-names
+ clocks Through "clock-names" and "clocks", external clocks
+ can be configured. If a clock names "extclk" exists,
+ it will be set to the mclk rate of the audio stream
+ and be used as clock provider of the DAI.
+
Example:
/* upstream device */
diff --git a/sound/soc/pxa/pxa-ssp.c b/sound/soc/pxa/pxa-ssp.c
index ff1e0bd8d407..69033e1a84e6 100644
--- a/sound/soc/pxa/pxa-ssp.c
+++ b/sound/soc/pxa/pxa-ssp.c
@@ -41,6 +41,7 @@
*/
struct ssp_priv {
struct ssp_device *ssp;
+ struct clk *extclk;
unsigned long ssp_clk;
unsigned int sysclk;
unsigned int dai_fmt;
@@ -205,6 +206,21 @@ static int pxa_ssp_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
u32 sscr0 = pxa_ssp_read_reg(ssp, SSCR0) &
~(SSCR0_ECS | SSCR0_NCS | SSCR0_MOD | SSCR0_ACS);
+ if (priv->extclk) {
+ int ret;
+
+ /*
+ * For DT based boards, if an extclk is given, use it
+ * here and configure PXA_SSP_CLK_EXT.
+ */
+
+ ret = clk_set_rate(priv->extclk, freq);
+ if (ret < 0)
+ return ret;
+
+ clk_id = PXA_SSP_CLK_EXT;
+ }
+
dev_dbg(&ssp->pdev->dev,
"pxa_ssp_set_dai_sysclk id: %d, clk_id %d, freq %u\n",
cpu_dai->id, clk_id, freq);
@@ -774,6 +790,15 @@ static int pxa_ssp_probe(struct snd_soc_dai *dai)
ret = -ENODEV;
goto err_priv;
}
+
+ priv->extclk = devm_clk_get(dev, "extclk");
+ if (IS_ERR(priv->extclk)) {
+ ret = PTR_ERR(priv->extclk);
+ if (ret == -EPROBE_DEFER)
+ return ret;
+
+ priv->extclk = NULL;
+ }
} else {
priv->ssp = pxa_ssp_request(dai->id + 1, "SoC audio");
if (priv->ssp == NULL) {