net: dsa: qca8k: add op to get ports netdev

In order that the LED trigger can blink the switch MAC ports LED, it
needs to know the netdev associated to the port. Add the callback to
return the struct device of the netdev.

Add an helper function qca8k_phy_to_port() to convert the phy back to
dsa_port index, as we reference LED port based on the internal PHY
index and needs to be converted back.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/qca/qca8k-leds.c

@@ -5,6 +5,18 @@
 #include "qca8k.h"
 #include "qca8k_leds.h"
 
+static u32 qca8k_phy_to_port(int phy)
+{
+	/* Internal PHY 0 has port at index 1.
+	 * Internal PHY 1 has port at index 2.
+	 * Internal PHY 2 has port at index 3.
+	 * Internal PHY 3 has port at index 4.
+	 * Internal PHY 4 has port at index 5.
+	 */
+
+	return phy + 1;
+}
+
 static int
 qca8k_get_enable_led_reg(int port_num, int led_num, struct qca8k_led_pattern_en *reg_info)
 {
@@ -314,6 +326,20 @@ qca8k_cled_hw_control_get(struct led_classdev *ldev, unsigned long *rules)
 	return 0;
 }
 
+static struct device *qca8k_cled_hw_control_get_device(struct led_classdev *ldev)
+{
+	struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev);
+	struct qca8k_priv *priv = led->priv;
+	struct dsa_port *dp;
+
+	dp = dsa_to_port(priv->ds, qca8k_phy_to_port(led->port_num));
+	if (!dp)
+		return NULL;
+	if (dp->slave)
+		return &dp->slave->dev;
+	return NULL;
+}
+
 static int
 qca8k_parse_port_leds(struct qca8k_priv *priv, struct fwnode_handle *port, int port_num)
 {
@@ -377,6 +403,7 @@ qca8k_parse_port_leds(struct qca8k_priv *priv, struct fwnode_handle *port, int p
 		port_led->cdev.hw_control_is_supported = qca8k_cled_hw_control_is_supported;
 		port_led->cdev.hw_control_set = qca8k_cled_hw_control_set;
 		port_led->cdev.hw_control_get = qca8k_cled_hw_control_get;
+		port_led->cdev.hw_control_get_device = qca8k_cled_hw_control_get_device;
 		port_led->cdev.hw_control_trigger = "netdev";
 		init_data.default_label = ":port";
 		init_data.fwnode = led;