Subject: Re: [net-next PATCH v4 05/14] net: phy: phy_device: Call into the PHY driver to set LED brightness

From: Michal Kubiak <[email-masked]>
Date: Fri, 17 Mar 2023 15:01:00 +0100

On Fri, Mar 17, 2023 at 03:31:16AM +0100, Christian Marangi wrote:
> From: Andrew Lunn <[email-masked]>
> 
> Linux LEDs can be software controlled via the brightness file in /sys.
> LED drivers need to implement a brightness_set function which the core
> will call. Implement an intermediary in phy_device, which will call
> into the phy driver if it implements the necessary function.
> 
> Signed-off-by: Andrew Lunn <[email-masked]>
> Signed-off-by: Christian Marangi <[email-masked]>
> ---

As I have already mentioned in my comments for the patch 4, the final
version of "phy_led_set_brightness()" can appear here (without
an intermediate step with a dummy implementation).

Thanks,
Michal

>  drivers/net/phy/phy_device.c | 15 ++++++++++++---
>  include/linux/phy.h          | 11 +++++++++++
>  2 files changed, 23 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index ee800f93c8c3..c7312a9e820d 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -2967,11 +2967,18 @@ static bool phy_drv_supports_irq(struct phy_driver *phydrv)
>  	return phydrv->config_intr && phydrv->handle_interrupt;
>  }
>  
> -/* Dummy implementation until calls into PHY driver are added */
>  static int phy_led_set_brightness(struct led_classdev *led_cdev,
>  				  enum led_brightness value)
>  {
> -	return 0;
> +	struct phy_led *phyled = to_phy_led(led_cdev);
> +	struct phy_device *phydev = phyled->phydev;
> +	int err;
> +
> +	mutex_lock(&phydev->lock);
> +	err = phydev->drv->led_brightness_set(phydev, phyled->index, value);
> +	mutex_unlock(&phydev->lock);
> +
> +	return err;
>  }
>  
>  static int of_phy_led(struct phy_device *phydev,
> @@ -2988,12 +2995,14 @@ static int of_phy_led(struct phy_device *phydev,
>  		return -ENOMEM;
>  
>  	cdev = &phyled->led_cdev;
> +	phyled->phydev = phydev;
>  
>  	err = of_property_read_u32(led, "reg", &phyled->index);
>  	if (err)
>  		return err;
>  
> -	cdev->brightness_set_blocking = phy_led_set_brightness;
> +	if (phydev->drv->led_brightness_set)
> +		cdev->brightness_set_blocking = phy_led_set_brightness;
>  	cdev->max_brightness = 1;
>  	init_data.devicename = dev_name(&phydev->mdio.dev);
>  	init_data.fwnode = of_fwnode_handle(led);
> diff --git a/include/linux/phy.h b/include/linux/phy.h
> index 88a77ff60be9..94fd21d5e145 100644
> --- a/include/linux/phy.h
> +++ b/include/linux/phy.h
> @@ -832,15 +832,19 @@ struct phy_plca_status {
>   * struct phy_led: An LED driven by the PHY
>   *
>   * @list: List of LEDs
> + * @phydev: PHY this LED is attached to
>   * @led_cdev: Standard LED class structure
>   * @index: Number of the LED
>   */
>  struct phy_led {
>  	struct list_head list;
> +	struct phy_device *phydev;
>  	struct led_classdev led_cdev;
>  	u32 index;
>  };
>  
> +#define to_phy_led(d) container_of(d, struct phy_led, led_cdev)
> +
>  /**
>   * struct phy_driver - Driver structure for a particular PHY type
>   *
> @@ -1063,6 +1067,13 @@ struct phy_driver {
>  	/** @get_plca_status: Return the current PLCA status info */
>  	int (*get_plca_status)(struct phy_device *dev,
>  			       struct phy_plca_status *plca_st);
> +
> +	/* Set a PHY LED brightness. Index indicates which of the PHYs
> +	 * led should be set. Value follows the standard LED class meaning,
> +	 * e.g. LED_OFF, LED_HALF, LED_FULL.
> +	 */
> +	int (*led_brightness_set)(struct phy_device *dev,
> +				  u32 index, enum led_brightness value);
>  };
>  #define to_phy_driver(d) container_of(to_mdio_common_driver(d),		\
>  				      struct phy_driver, mdiodrv)
> -- 
> 2.39.2
>