Re: [PATCH 1/3] pwm: Provide wrappers for storing and getting private data

[Lee Jones <lee@kernel.org>]

On Fri, 24 Nov 2023, Uwe Kleine-König wrote:

> Also call pwmchip_set_drvdata() in pwmchip_alloc() to have a sane
> default. Might replace pwmchip_priv()?!
> 
> After struct pwm_chip got its own struct device, this can make use of
> dev_get_drvdata() and dev_set_drvdata() on that device.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> ---
>  drivers/pwm/core.c  |  2 ++
>  include/linux/pwm.h | 19 +++++++++++++++++++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
> index 17577a1c4efc..0cbce704cc0b 100644
> --- a/drivers/pwm/core.c
> +++ b/drivers/pwm/core.c
> @@ -216,6 +216,8 @@ struct pwm_chip *devm_pwmchip_alloc(struct device *parent, unsigned int npwm, si
>  	chip->dev = parent;
>  	chip->npwm = npwm;
>  
> +	pwmchip_set_drvdata(chip, pwmchip_priv(chip));
> +
>  	return chip;
>  }
>  EXPORT_SYMBOL_GPL(devm_pwmchip_alloc);
> diff --git a/include/linux/pwm.h b/include/linux/pwm.h
> index 3c62cf329ee0..7a32ac687717 100644
> --- a/include/linux/pwm.h
> +++ b/include/linux/pwm.h
> @@ -302,6 +302,7 @@ struct pwm_chip {
>  
>  	/* only used internally by the PWM framework */
>  	struct pwm_device *pwms;
> +	void *drvdata;

I appreciate that this may be temporary, but why not use the precedent
already set by struct device?

  void            *driver_data;

>  };
>  
>  static inline struct device *pwmchip_parent(struct pwm_chip *chip)
> @@ -309,6 +310,24 @@ static inline struct device *pwmchip_parent(struct pwm_chip *chip)
>  	return chip->dev;
>  }
>  
> +static inline void *pwmchip_get_drvdata(struct pwm_chip *chip)
> +{
> +	/*
> +	 * After pwm_chip got a dedicated struct device, this can be replaced by
> +	 * dev_get_drvdata(&chip->dev);
> +	 */
> +	return chip->drvdata;
> +}
> +
> +static inline void pwmchip_set_drvdata(struct pwm_chip *chip, void *data)
> +{
> +	/*
> +	 * After pwm_chip got a dedicated struct device, this can be replaced by
> +	 * dev_set_drvdata(&chip->dev, data);
> +	 */
> +	chip->drvdata = data;
> +}
> +
>  #if IS_ENABLED(CONFIG_PWM)
>  /* PWM user APIs */
>  int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state);
> -- 
> 2.42.0
> 

-- 
Lee Jones [李琼斯]