Re: [PATCH] ASoC: wm8962: Let CODEC driver enable and disable its own MCLK

From: Nicolin Chen
Date: Mon Jul 28 2014 - 07:25:05 EST


PLEASE IGNORE THIS VERSION

On Mon, Jul 28, 2014 at 06:56:01PM +0800, Nicolin Chen wrote:
> snd_soc_open() will trigger pm_runtime resume() which will then enable
> the regulator and initialization. So we should make sure the MCLK is
> enabled before this resume().
>
> Previously we let the machine driver get the clock and enable it in
> its probe(). However, considering about power saving, it'll be better
> to enable it when it's going to be used and disable it after using.
>
> So this patch just simply adds clk_get() and clk_enable() to WM8962
> driver. Meanwhile, it marks clock pointer to NULL if no clock assigned
> to it so it will not break any current function.
>
> Signed-off-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>

Sorry, the patch has some problem. I'll send v2 to fix it.

Please ignore this version.

Thank you,
Nicolin

> ---
> include/sound/wm8962.h | 1 +
> sound/soc/codecs/wm8962.c | 11 +++++++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/include/sound/wm8962.h b/include/sound/wm8962.h
> index 79e6d42..0af7c16 100644
> --- a/include/sound/wm8962.h
> +++ b/include/sound/wm8962.h
> @@ -37,6 +37,7 @@
> #define WM8962_GPIO_FN_MICSCD 22
>
> struct wm8962_pdata {
> + struct clk *mclk;
> int gpio_base;
> u32 gpio_init[WM8962_MAX_GPIO];
>
> diff --git a/sound/soc/codecs/wm8962.c b/sound/soc/codecs/wm8962.c
> index ca2fda9..256ae51 100644
> --- a/sound/soc/codecs/wm8962.c
> +++ b/sound/soc/codecs/wm8962.c
> @@ -14,6 +14,7 @@
> #include <linux/module.h>
> #include <linux/moduleparam.h>
> #include <linux/init.h>
> +#include <linux/clk.h>
> #include <linux/delay.h>
> #include <linux/pm.h>
> #include <linux/gcd.h>
> @@ -3541,6 +3542,8 @@ static int wm8962_set_pdata_from_of(struct i2c_client *i2c,
> pdata->gpio_init[i] = 0x0;
> }
>
> + pdata->mclk = devm_clk_get(&i2c->dev, NULL);
> +
> return 0;
> }
>
> @@ -3572,6 +3575,10 @@ static int wm8962_i2c_probe(struct i2c_client *i2c,
> return ret;
> }
>
> + /* Mark the mclk pointer to NULL if no mclk assigned */
> + if (IS_ERR(pdata->mclk))
> + pdata->mclk = NULL;
> +
> for (i = 0; i < ARRAY_SIZE(wm8962->supplies); i++)
> wm8962->supplies[i].supply = wm8962_supply_names[i];
>
> @@ -3780,6 +3787,8 @@ static int wm8962_runtime_resume(struct device *dev)
> struct wm8962_priv *wm8962 = dev_get_drvdata(dev);
> int ret;
>
> + clk_prepare_enable(wm8962->pdata.mclk);
> +
> ret = regulator_bulk_enable(ARRAY_SIZE(wm8962->supplies),
> wm8962->supplies);
> if (ret != 0) {
> @@ -3839,6 +3848,8 @@ static int wm8962_runtime_suspend(struct device *dev)
> regulator_bulk_disable(ARRAY_SIZE(wm8962->supplies),
> wm8962->supplies);
>
> + clk_disable_unprepare(wm8962->pdata.mclk);
> +
> return 0;
> }
> #endif
> --
> 1.8.4
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/