[alsa-devel] [PATCH 4/6] mfd: arizona: Add gating of external MCLKn clocks

[Lee Jones]

On Fri, 02 Sep 2016, Charles Keepax wrote:

> From: Sylwester Nawrocki <s.nawrocki at samsung.com>
> 
> This patch adds requesting of the clocks supplied on MCLK1, MCLK2 pins,
> gating of the 32k clock is added to the arizona_clk32k_enable(),
> arizona_clk32k_disable() helpers.
> 
> It's a temporary change until the CODEC's clock controller gets exposed
> through the clk API and is helpful for board configurations where the
> MCLK clocks are not provided by always on oscillators.
> 
> Signed-off-by: Sylwester Nawrocki <s.nawrocki at samsung.com>
> Signed-off-by: Charles Keepax <ckeepax at opensource.wolfsonmicro.com>
> ---
>  drivers/mfd/arizona-core.c       | 30 ++++++++++++++++++++++++++++--
>  include/linux/mfd/arizona/core.h |  9 +++++++++
>  2 files changed, 37 insertions(+), 2 deletions(-)

Acked-for-MFD-by: Lee Jones <lee.jones at linaro.org>

Can I take this?

> diff --git a/drivers/mfd/arizona-core.c b/drivers/mfd/arizona-core.c
> index e4f97b3..4fa0fae 100644
> --- a/drivers/mfd/arizona-core.c
> +++ b/drivers/mfd/arizona-core.c
> @@ -10,6 +10,7 @@
>   * published by the Free Software Foundation.
>   */
>  
> +#include <linux/clk.h>
>  #include <linux/delay.h>
>  #include <linux/err.h>
>  #include <linux/gpio.h>
> @@ -49,7 +50,15 @@ int arizona_clk32k_enable(struct arizona *arizona)
>  		case ARIZONA_32KZ_MCLK1:
>  			ret = pm_runtime_get_sync(arizona->dev);
>  			if (ret != 0)
> -				goto out;
> +				goto err_ref;
> +			ret = clk_prepare_enable(arizona->mclk[ARIZONA_MCLK1]);
> +			if (ret != 0)
> +				goto err_pm;
> +			break;
> +		case ARIZONA_32KZ_MCLK2:
> +			ret = clk_prepare_enable(arizona->mclk[ARIZONA_MCLK2]);
> +			if (ret != 0)
> +				goto err_ref;
>  			break;
>  		}
>  
> @@ -58,7 +67,9 @@ int arizona_clk32k_enable(struct arizona *arizona)
>  					 ARIZONA_CLK_32K_ENA);
>  	}
>  
> -out:
> +err_pm:
> +	pm_runtime_put_sync(arizona->dev);
> +err_ref:
>  	if (ret != 0)
>  		arizona->clk32k_ref--;
>  
> @@ -83,6 +94,10 @@ int arizona_clk32k_disable(struct arizona *arizona)
>  		switch (arizona->pdata.clk32k_src) {
>  		case ARIZONA_32KZ_MCLK1:
>  			pm_runtime_put_sync(arizona->dev);
> +			clk_disable_unprepare(arizona->mclk[ARIZONA_MCLK1]);
> +			break;
> +		case ARIZONA_32KZ_MCLK2:
> +			clk_disable_unprepare(arizona->mclk[ARIZONA_MCLK2]);
>  			break;
>  		}
>  	}
> @@ -1000,6 +1015,7 @@ static const struct mfd_cell wm8998_devs[] = {
>  
>  int arizona_dev_init(struct arizona *arizona)
>  {
> +	const char * const mclk_name[] = { "mclk1", "mclk2" };
>  	struct device *dev = arizona->dev;
>  	const char *type_name = NULL;
>  	unsigned int reg, val, mask;
> @@ -1016,6 +1032,16 @@ int arizona_dev_init(struct arizona *arizona)
>  	else
>  		arizona_of_get_core_pdata(arizona);
>  
> +	BUILD_BUG_ON(ARRAY_SIZE(arizona->mclk) != ARRAY_SIZE(mclk_name));
> +	for (i = 0; i < ARRAY_SIZE(arizona->mclk); i++) {
> +		arizona->mclk[i] = devm_clk_get(arizona->dev, mclk_name[i]);
> +		if (IS_ERR(arizona->mclk[i])) {
> +			dev_info(arizona->dev, "Failed to get %s: %ld\n",
> +				 mclk_name[i], PTR_ERR(arizona->mclk[i]));
> +			arizona->mclk[i] = NULL;
> +		}
> +	}
> +
>  	regcache_cache_only(arizona->regmap, true);
>  
>  	switch (arizona->type) {
> diff --git a/include/linux/mfd/arizona/core.h b/include/linux/mfd/arizona/core.h
> index 58ab4c0..b9909bb 100644
> --- a/include/linux/mfd/arizona/core.h
> +++ b/include/linux/mfd/arizona/core.h
> @@ -13,6 +13,7 @@
>  #ifndef _WM_ARIZONA_CORE_H
>  #define _WM_ARIZONA_CORE_H
>  
> +#include <linux/clk.h>
>  #include <linux/interrupt.h>
>  #include <linux/notifier.h>
>  #include <linux/regmap.h>
> @@ -21,6 +22,12 @@
>  
>  #define ARIZONA_MAX_CORE_SUPPLIES 2
>  
> +enum {
> +	ARIZONA_MCLK1,
> +	ARIZONA_MCLK2,
> +	ARIZONA_NUM_MCLK
> +};
> +
>  enum arizona_type {
>  	WM5102 = 1,
>  	WM5110 = 2,
> @@ -139,6 +146,8 @@ struct arizona {
>  	struct mutex clk_lock;
>  	int clk32k_ref;
>  
> +	struct clk *mclk[ARIZONA_NUM_MCLK];
> +
>  	bool ctrlif_error;
>  
>  	struct snd_soc_dapm_context *dapm;

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog