[STLinux Kernel] [[PATCH v2] 07/11] pwm: sti: Supply PWM Capture clock handling

[Peter Griffin]

Hi Lee,

On Fri, 22 Apr 2016, Lee Jones wrote:

> ST's PWM IP is supplied by 2 different clocks.  One for PWM
> Output and the other for Capture.  This patch provides clock
> handling for the latter.
> 
> Signed-off-by: Lee Jones <lee.jones at linaro.org>
> ---
>  drivers/pwm/pwm-sti.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/drivers/pwm/pwm-sti.c b/drivers/pwm/pwm-sti.c
> index 2f61e1e..78979d0 100644
> --- a/drivers/pwm/pwm-sti.c
> +++ b/drivers/pwm/pwm-sti.c
> @@ -74,6 +74,7 @@ struct sti_pwm_compat_data {
>  struct sti_pwm_chip {
>  	struct device *dev;
>  	struct clk *pwm_clk;
> +	struct clk *cpt_clk;
>  	struct regmap *regmap;
>  	struct sti_pwm_compat_data *cdata;
>  	struct regmap_field *prescale_low;
> @@ -183,6 +184,10 @@ static int sti_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
>  		if (ret)
>  			return ret;
>  
> +		ret = clk_enable(pc->cpt_clk);
> +		if (ret)
> +			return ret;
> +
>  		if (!period_same) {
>  			ret = sti_pwm_get_prescale(pc, period_ns, &prescale);
>  			if (ret)
> @@ -227,6 +232,7 @@ static int sti_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
>  
>  clk_dis:
>  	clk_disable(pc->pwm_clk);
> +	clk_disable(pc->cpt_clk);
>  	return ret;
>  }
>  
> @@ -246,6 +252,10 @@ static int sti_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
>  		if (ret)
>  			goto out;
>  
> +		ret = clk_enable(pc->cpt_clk);
> +		if (ret)
> +			goto out;
> +
>  		ret = regmap_field_write(pc->pwm_out_en, 1);
>  		if (ret) {
>  			dev_err(dev, "failed to enable PWM device:%d\n",
> @@ -271,6 +281,7 @@ static void sti_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
>  	regmap_field_write(pc->pwm_out_en, 0);
>  
>  	clk_disable(pc->pwm_clk);
> +	clk_disable(pc->cpt_clk);
>  	mutex_unlock(&pc->sti_pwm_lock);
>  }
>  
> @@ -390,6 +401,18 @@ static int sti_pwm_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> +	pc->cpt_clk = of_clk_get_by_name(dev->of_node, "capture");
> +	if (IS_ERR(pc->cpt_clk)) {
> +		dev_err(dev, "failed to get PWM capture clock\n");
> +		return PTR_ERR(pc->cpt_clk);
> +	}

The dt binding document pwm-st.txt also needs updating for this extra clock.

regards,

Peter.