[PATCH net-next 1/2] net: phy: add LED dimming support

[Aleksander Jan Bajkowski]

Some PHYs support LED dimming. The use case is a router that dims LEDs
at night. PHYs from different manufacturers support a different number of
brightness levels, so it was necessary to extend the API with the
led_max_brightness() function. If this function is omitted, a default
value is used, assuming that only two levels are supported.

Signed-off-by: Aleksander Jan Bajkowski <olek2@xxxxx>
Reviewed-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
---
 drivers/net/phy/phy_device.c | 7 ++++++-
 include/linux/phy.h          | 7 +++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 46713d27412b..f9631f093baa 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -3351,7 +3351,12 @@ static int of_phy_led(struct phy_device *phydev,
 
 	cdev->hw_control_get_device = phy_led_hw_control_get_device;
 #endif
-	cdev->max_brightness = 1;
+	if (phydev->drv->led_max_brightness)
+		cdev->max_brightness =
+			phydev->drv->led_max_brightness(phydev, index);
+	else
+		cdev->max_brightness = 1;
+
 	init_data.devicename = dev_name(&phydev->mdio.dev);
 	init_data.fwnode = of_fwnode_handle(led);
 	init_data.devname_mandatory = true;
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 19f076a71f94..248a47c8817b 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1216,6 +1216,13 @@ struct phy_driver {
 	int (*led_brightness_set)(struct phy_device *dev,
 				  u8 index, enum led_brightness value);
 
+	/**
+	 * &led_max_brightness: Maximum number of brightness levels
+	 * supported by hardware. When only two levels are supported
+	 * i.e. LED_ON and LED_OFF the function can be omitted.
+	 */
+	int (*led_max_brightness)(struct phy_device *dev, u8 index);
+
 	/**
 	 * @led_blink_set: Set a PHY LED blinking.  Index indicates
 	 * which of the PHYs led should be configured to blink. Delays
-- 
2.39.5