Re: [PATCH v15 2/4] phy: Add media type and speed serdes configuration interfaces

[Leon Romanovsky]

On Thu, Feb 18, 2021 at 05:14:49PM +0100, Steen Hegelund wrote:
> Provide new phy configuration interfaces for media type and speed that
> allows e.g. PHYs used for ethernet to be configured with this
> information.
>
> Signed-off-by: Lars Povlsen <lars.povlsen@xxxxxxxxxxxxx>
> Signed-off-by: Steen Hegelund <steen.hegelund@xxxxxxxxxxxxx>
> Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
> Reviewed-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> ---
>  drivers/phy/phy-core.c  | 30 ++++++++++++++++++++++++++++++
>  include/linux/phy/phy.h | 26 ++++++++++++++++++++++++++
>  2 files changed, 56 insertions(+)
>
> diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
> index 71cb10826326..ccb575b13777 100644
> --- a/drivers/phy/phy-core.c
> +++ b/drivers/phy/phy-core.c
> @@ -373,6 +373,36 @@ int phy_set_mode_ext(struct phy *phy, enum phy_mode mode, int submode)
>  }
>  EXPORT_SYMBOL_GPL(phy_set_mode_ext);
>
> +int phy_set_media(struct phy *phy, enum phy_media media)
> +{
> +	int ret;
> +
> +	if (!phy || !phy->ops->set_media)
> +		return 0;
> +
> +	mutex_lock(&phy->mutex);
> +	ret = phy->ops->set_media(phy, media);
> +	mutex_unlock(&phy->mutex);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(phy_set_media);
> +
> +int phy_set_speed(struct phy *phy, int speed)
> +{
> +	int ret;
> +
> +	if (!phy || !phy->ops->set_speed)
> +		return 0;
> +
> +	mutex_lock(&phy->mutex);
> +	ret = phy->ops->set_speed(phy, speed);
> +	mutex_unlock(&phy->mutex);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(phy_set_speed);
> +
>  int phy_reset(struct phy *phy)
>  {
>  	int ret;
> diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h
> index e435bdb0bab3..0ed434d02196 100644
> --- a/include/linux/phy/phy.h
> +++ b/include/linux/phy/phy.h
> @@ -44,6 +44,12 @@ enum phy_mode {
>  	PHY_MODE_DP
>  };
>
> +enum phy_media {
> +	PHY_MEDIA_DEFAULT,
> +	PHY_MEDIA_SR,
> +	PHY_MEDIA_DAC,
> +};
> +
>  /**
>   * union phy_configure_opts - Opaque generic phy configuration
>   *
> @@ -64,6 +70,8 @@ union phy_configure_opts {
>   * @power_on: powering on the phy
>   * @power_off: powering off the phy
>   * @set_mode: set the mode of the phy
> + * @set_media: set the media type of the phy (optional)
> + * @set_speed: set the speed of the phy (optional)
>   * @reset: resetting the phy
>   * @calibrate: calibrate the phy
>   * @release: ops to be performed while the consumer relinquishes the PHY
> @@ -75,6 +83,8 @@ struct phy_ops {
>  	int	(*power_on)(struct phy *phy);
>  	int	(*power_off)(struct phy *phy);
>  	int	(*set_mode)(struct phy *phy, enum phy_mode mode, int submode);
> +	int	(*set_media)(struct phy *phy, enum phy_media media);
> +	int	(*set_speed)(struct phy *phy, int speed);
>
>  	/**
>  	 * @configure:
> @@ -215,6 +225,8 @@ int phy_power_off(struct phy *phy);
>  int phy_set_mode_ext(struct phy *phy, enum phy_mode mode, int submode);
>  #define phy_set_mode(phy, mode) \
>  	phy_set_mode_ext(phy, mode, 0)
> +int phy_set_media(struct phy *phy, enum phy_media media);
> +int phy_set_speed(struct phy *phy, int speed);
>  int phy_configure(struct phy *phy, union phy_configure_opts *opts);
>  int phy_validate(struct phy *phy, enum phy_mode mode, int submode,
>  		 union phy_configure_opts *opts);
> @@ -344,6 +356,20 @@ static inline int phy_set_mode_ext(struct phy *phy, enum phy_mode mode,
>  #define phy_set_mode(phy, mode) \
>  	phy_set_mode_ext(phy, mode, 0)
>
> +static inline int phy_set_media(struct phy *phy, enum phy_media media)
> +{
> +	if (!phy)
> +		return 0;

I'm curious, why do you check for the NULL in all newly introduced functions?
How is it possible that calls to phy_*() supply NULL as the main struct?

Thanks

> +	return -ENODEV;
> +}
> +
> +static inline int phy_set_speed(struct phy *phy, int speed)
> +{
> +	if (!phy)
> +		return 0;
> +	return -ENODEV;
> +}
> +
>  static inline enum phy_mode phy_get_mode(struct phy *phy)
>  {
>  	return PHY_MODE_INVALID;
> --
> 2.30.0
>