[U-Boot] [PATCH] power: regulator: pwm: support pwm polarity setting

[Jaehoon Chung]

Hi Kever,

On 04/07/2017 08:02 PM, Kever Yang wrote:
> The latest kernel PWM drivers enable the polarity settings. When system
> run from U-Boot to kerenl, if there are differences in polarity set or
> duty cycle, the PMW will re-init:
>   close -> set polarity and duty cycle -> enable the PWM.
> The power supply controled by pwm regulator may have voltage shaking,
> which lead to the system not stable.
> 
> Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
> ---
> 
>  drivers/power/regulator/pwm_regulator.c | 12 ++++++++++--
>  drivers/pwm/pwm-uclass.c                | 10 ++++++++++
>  drivers/pwm/rk_pwm.c                    | 17 ++++++++++++++++-
>  include/pwm.h                           |  9 +++++++++
>  4 files changed, 45 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/power/regulator/pwm_regulator.c b/drivers/power/regulator/pwm_regulator.c
> index 4875238..f8a6712 100644
> --- a/drivers/power/regulator/pwm_regulator.c
> +++ b/drivers/power/regulator/pwm_regulator.c
> @@ -24,6 +24,8 @@ struct pwm_regulator_info {
>  	int pwm_id;
>  	/* the period of one PWM cycle */
>  	int period_ns;
> +	/* the polarity of one PWM */
> +	int polarity;
>  	struct udevice *pwm;
>  	/* initialize voltage of regulator */
>  	unsigned int init_voltage;
> @@ -49,7 +51,7 @@ static int pwm_voltage_to_duty_cycle_percentage(struct udevice *dev, int req_uV)
>  	int max_uV = priv->max_voltage;
>  	int diff = max_uV - min_uV;
>  
> -	return 100 - (((req_uV * 100) - (min_uV * 100)) / diff);
> +	return ((req_uV * 100) - (min_uV * 100)) / diff;
>  }
>  
>  static int pwm_regulator_get_voltage(struct udevice *dev)
> @@ -67,6 +69,12 @@ static int pwm_regulator_set_voltage(struct udevice *dev, int uvolt)
>  
>  	duty_cycle = pwm_voltage_to_duty_cycle_percentage(dev, uvolt);
>  
> +	ret = pwm_set_init(priv->pwm, priv->pwm_id, priv->polarity);
> +	if (ret) {
> +		dev_err(dev, "Failed to init PWM\n");
> +		return ret;
> +	}
> +
>  	ret = pwm_set_config(priv->pwm, priv->pwm_id,
>  			(priv->period_ns / 100) * duty_cycle, priv->period_ns);
>  	if (ret) {
> @@ -97,9 +105,9 @@ static int pwm_regulator_ofdata_to_platdata(struct udevice *dev)
>  		debug("%s: Cannot get PWM phandle: ret=%d\n", __func__, ret);
>  		return ret;
>  	}
> -	/* TODO: pwm_id here from device tree if needed */
>  
>  	priv->period_ns = args.args[1];
> +	priv->polarity = args.args[2];
>  
>  	priv->init_voltage = fdtdec_get_int(blob, node,
>  			"regulator-init-microvolt", -1);
> diff --git a/drivers/pwm/pwm-uclass.c b/drivers/pwm/pwm-uclass.c
> index c2200af..287a7f3 100644
> --- a/drivers/pwm/pwm-uclass.c
> +++ b/drivers/pwm/pwm-uclass.c
> @@ -9,6 +9,16 @@
>  #include <dm.h>
>  #include <pwm.h>
>  
> +int pwm_set_init(struct udevice *dev, uint channel, uint polarity)
> +{
> +	struct pwm_ops *ops = pwm_get_ops(dev);
> +
> +	if (!ops->set_init)
> +		return -ENOSYS;
> +
> +	return ops->set_init(dev, channel, polarity);
> +}
> +
>  int pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
>  		   uint duty_ns)
>  {
> diff --git a/drivers/pwm/rk_pwm.c b/drivers/pwm/rk_pwm.c
> index 9254f5b..5ff1e00 100644
> --- a/drivers/pwm/rk_pwm.c
> +++ b/drivers/pwm/rk_pwm.c
> @@ -21,8 +21,22 @@ DECLARE_GLOBAL_DATA_PTR;
>  struct rk_pwm_priv {
>  	struct rk3288_pwm *regs;
>  	ulong freq;
> +	uint enable_conf;
>  };
>  
> +static int rk_pwm_set_init(struct udevice *dev, uint channel, uint polarity)
> +{

"channel" is need?

> +	struct rk_pwm_priv *priv = dev_get_priv(dev);
> +
> +	debug("%s: polarity=%u\n", __func__, polarity);
> +	if (polarity)
> +		priv->enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSTIVE;
> +	else
> +		priv->enable_conf |= PWM_DUTY_POSTIVE | PWM_INACTIVE_NEGATIVE;
> +
> +	return 0;
> +}
> +
>  static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
>  			     uint duty_ns)
>  {
> @@ -32,7 +46,7 @@ static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
>  
>  	debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns);
>  	writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE |
> -		PWM_CONTINUOUS | PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE |
> +		PWM_CONTINUOUS | priv->enable_conf |
>  		RK_PWM_DISABLE,
>  		&regs->ctrl);
>  
> @@ -83,6 +97,7 @@ static int rk_pwm_probe(struct udevice *dev)
>  }
>  
>  static const struct pwm_ops rk_pwm_ops = {
> +	.set_init	= rk_pwm_set_init,
>  	.set_config	= rk_pwm_set_config,
>  	.set_enable	= rk_pwm_set_enable,
>  };
> diff --git a/include/pwm.h b/include/pwm.h
> index 851915e..a66ee1f 100644
> --- a/include/pwm.h
> +++ b/include/pwm.h
> @@ -14,6 +14,15 @@
>  /* struct pwm_ops: Operations for the PWM uclass */
>  struct pwm_ops {
>  	/**
> +	 * set_init() - Set the PWM invert
> +	 *
> +	 * @dev:        PWM device to update
> +	 * @channel:    PWM channel to update
> +	 * @polarity:  PWM invert polarity
> +	 * @return 0 if OK, -ve on error
> +	 */
> +	int (*set_init)(struct udevice *dev, uint channel, uint polarity);

Is there a reason about using int type? It's always return 0...
Otherwise do you have a plan to use "int" type?

Best Regards,
Jaehoon Chung

> +	/**
>  	 * set_config() - Set the PWM configuration
>  	 *
>  	 * @dev:	PWM device to update
>