[net-next PATCH v10 3/5] net: phy: add support for PHY LEDs polarity modes

From: Christian Marangi
Date: Thu Jan 25 2024 - 15:38:35 EST


Add support for PHY LEDs polarity modes. Some PHY require LED to be set
to active low to be turned ON. Adds support for this by declaring
active-low property in DT.

PHY driver needs to declare .led_polarity_set() to configure LED
polarity modes. Function will pass the index with the LED index and a
bitmap with all the required modes to set.

Current supported modes are:
- active-low with the flag PHY_LED_ACTIVE_LOW. LED is set to active-low
to turn it ON.
- inactive-high-impedance with the flag PHY_LED_INACTIVE_HIGH_IMPEDANCE.
LED is set to high impedance to turn it OFF.

Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
---
Changes v10:
- Add Review tag
Changes v9:
- Make LED probe fail if modes asked but not supported
- Fix wrong function description
Changes v5:
- Rework to LED modes bitmap
Changes v4:
- Drop for global active-low
- Rework to polarity option (for marvell10g series support)
Changes v3:
- Out of RFC
Changes v2:
- Add this patch

drivers/net/phy/phy_device.c | 16 ++++++++++++++++
include/linux/phy.h | 22 ++++++++++++++++++++++
2 files changed, 38 insertions(+)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 3611ea64875e..dd778c7fde1d 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -3097,6 +3097,7 @@ static int of_phy_led(struct phy_device *phydev,
struct device *dev = &phydev->mdio.dev;
struct led_init_data init_data = {};
struct led_classdev *cdev;
+ unsigned long modes = 0;
struct phy_led *phyled;
u32 index;
int err;
@@ -3114,6 +3115,21 @@ static int of_phy_led(struct phy_device *phydev,
if (index > U8_MAX)
return -EINVAL;

+ if (of_property_read_bool(led, "active-low"))
+ set_bit(PHY_LED_ACTIVE_LOW, &modes);
+ if (of_property_read_bool(led, "inactive-high-impedance"))
+ set_bit(PHY_LED_INACTIVE_HIGH_IMPEDANCE, &modes);
+
+ if (modes) {
+ /* Return error if asked to set polarity modes but not supported */
+ if (!phydev->drv->led_polarity_set)
+ return -EINVAL;
+
+ err = phydev->drv->led_polarity_set(phydev, index, modes);
+ if (err)
+ return err;
+ }
+
phyled->index = index;
if (phydev->drv->led_brightness_set)
cdev->brightness_set_blocking = phy_led_set_brightness;
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 684efaeca07c..c9994a59ca2e 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -852,6 +852,15 @@ struct phy_plca_status {
bool pst;
};

+/* Modes for PHY LED configuration */
+enum phy_led_modes {
+ PHY_LED_ACTIVE_LOW = 0,
+ PHY_LED_INACTIVE_HIGH_IMPEDANCE = 1,
+
+ /* keep it last */
+ __PHY_LED_MODES_NUM,
+};
+
/**
* struct phy_led: An LED driven by the PHY
*
@@ -1145,6 +1154,19 @@ struct phy_driver {
int (*led_hw_control_get)(struct phy_device *dev, u8 index,
unsigned long *rules);

+ /**
+ * @led_polarity_set: Set the LED polarity modes
+ * @dev: PHY device which has the LED
+ * @index: Which LED of the PHY device
+ * @modes: bitmap of LED polarity modes
+ *
+ * Configure LED with all the required polarity modes in @modes
+ * to make it correctly turn ON or OFF.
+ *
+ * Returns 0, or an error code.
+ */
+ int (*led_polarity_set)(struct phy_device *dev, int index,
+ unsigned long modes);
};
#define to_phy_driver(d) container_of(to_mdio_common_driver(d), \
struct phy_driver, mdiodrv)
--
2.43.0