ASoC: davinci-evm: Add named clock reference to DT bindings
The referenced clock is used to get codec clock rate and the clock is
disabled and enabled in startup and shutdown snd_soc_ops call
backs. The change is also documented in DT bindigs document.
Signed-off-by: Jyri Sarha <jsarha@ti.com>
cc: bcousson@baylibre.com
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/soc/davinci/davinci-evm.c b/sound/soc/davinci/davinci-evm.c
index 70ff377..d3e4cb0 100644
--- a/sound/soc/davinci/davinci-evm.c
+++ b/sound/soc/davinci/davinci-evm.c
@@ -17,6 +17,7 @@
#include <linux/platform_data/edma.h>
#include <linux/i2c.h>
#include <linux/of_platform.h>
+#include <linux/clk.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/soc.h>
@@ -30,9 +31,34 @@
#include "davinci-i2s.h"
struct snd_soc_card_drvdata_davinci {
+ struct clk *mclk;
unsigned sysclk;
};
+static int evm_startup(struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct snd_soc_card *soc_card = rtd->codec->card;
+ struct snd_soc_card_drvdata_davinci *drvdata =
+ snd_soc_card_get_drvdata(soc_card);
+
+ if (drvdata->mclk)
+ return clk_prepare_enable(drvdata->mclk);
+
+ return 0;
+}
+
+static void evm_shutdown(struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct snd_soc_card *soc_card = rtd->codec->card;
+ struct snd_soc_card_drvdata_davinci *drvdata =
+ snd_soc_card_get_drvdata(soc_card);
+
+ if (drvdata->mclk)
+ clk_disable_unprepare(drvdata->mclk);
+}
+
static int evm_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
@@ -59,6 +85,8 @@
}
static struct snd_soc_ops evm_ops = {
+ .startup = evm_startup,
+ .shutdown = evm_shutdown,
.hw_params = evm_hw_params,
};
@@ -348,6 +376,7 @@
of_match_device(of_match_ptr(davinci_evm_dt_ids), &pdev->dev);
struct snd_soc_dai_link *dai = (struct snd_soc_dai_link *) match->data;
struct snd_soc_card_drvdata_davinci *drvdata = NULL;
+ struct clk *mclk;
int ret = 0;
evm_soc_card.dai_link = dai;
@@ -367,13 +396,38 @@
if (ret)
return ret;
+ mclk = devm_clk_get(&pdev->dev, "mclk");
+ if (PTR_ERR(mclk) == -EPROBE_DEFER) {
+ return -EPROBE_DEFER;
+ } else if (IS_ERR(mclk)) {
+ dev_dbg(&pdev->dev, "mclk not found.\n");
+ mclk = NULL;
+ }
+
drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
+ drvdata->mclk = mclk;
+
ret = of_property_read_u32(np, "ti,codec-clock-rate", &drvdata->sysclk);
- if (ret < 0)
- return -EINVAL;
+
+ if (ret < 0) {
+ if (!drvdata->mclk) {
+ dev_err(&pdev->dev,
+ "No clock or clock rate defined.\n");
+ return -EINVAL;
+ }
+ drvdata->sysclk = clk_get_rate(drvdata->mclk);
+ } else if (drvdata->mclk) {
+ unsigned int requestd_rate = drvdata->sysclk;
+ clk_set_rate(drvdata->mclk, drvdata->sysclk);
+ drvdata->sysclk = clk_get_rate(drvdata->mclk);
+ if (drvdata->sysclk != requestd_rate)
+ dev_warn(&pdev->dev,
+ "Could not get requested rate %u using %u.\n",
+ requestd_rate, drvdata->sysclk);
+ }
snd_soc_card_set_drvdata(&evm_soc_card, drvdata);
ret = devm_snd_soc_register_card(&pdev->dev, &evm_soc_card);