leds: trigger: netdev: Configure LED blink interval for HW offload

In case a PHY LED implements .blink_set callback to set LED blink
interval, call it even if .hw_control is already set, as that LED
blink interval likely controls the blink rate of that HW offloaded
LED. For PHY LEDs, that can be their activity blinking interval.

The software blinking is not affected by this change.

With this change, the LED interval setting looks something like this:
$ echo netdev > /sys/class/leds/led:green:lan/trigger
$ echo 1 > /sys/class/leds/led:green:lan/brightness
$ echo 250 > /sys/class/leds/led:green:lan/interval

Signed-off-by: Marek Vasut <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Lee Jones <[email protected]>

Author: Marek Vasut

drivers/leds/trigger/ledtrig-netdev.c

@@ -68,6 +68,7 @@ struct led_netdev_data {
 	unsigned int last_activity;
 
 	unsigned long mode;
+	unsigned long blink_delay;
 	int link_speed;
 	__ETHTOOL_DECLARE_LINK_MODE_MASK(supported_link_modes);
 	u8 duplex;
@@ -86,6 +87,10 @@ static void set_baseline_state(struct led_netdev_data *trigger_data)
 	/* Already validated, hw control is possible with the requested mode */
 	if (trigger_data->hw_control) {
 		led_cdev->hw_control_set(led_cdev, trigger_data->mode);
+		if (led_cdev->blink_set) {
+			led_cdev->blink_set(led_cdev, &trigger_data->blink_delay,
+					    &trigger_data->blink_delay);
+		}
 
 		return;
 	}
@@ -454,10 +459,11 @@ static ssize_t interval_store(struct device *dev,
 			      size_t size)
 {
 	struct led_netdev_data *trigger_data = led_trigger_get_drvdata(dev);
+	struct led_classdev *led_cdev = trigger_data->led_cdev;
 	unsigned long value;
 	int ret;
 
-	if (trigger_data->hw_control)
+	if (trigger_data->hw_control && !led_cdev->blink_set)
 		return -EINVAL;
 
 	ret = kstrtoul(buf, 0, &value);
@@ -466,9 +472,13 @@ static ssize_t interval_store(struct device *dev,
 
 	/* impose some basic bounds on the timer interval */
 	if (value >= 5 && value <= 10000) {
-		cancel_delayed_work_sync(&trigger_data->work);
+		if (trigger_data->hw_control) {
+			trigger_data->blink_delay = value;
+		} else {
+			cancel_delayed_work_sync(&trigger_data->work);
 
-		atomic_set(&trigger_data->interval, msecs_to_jiffies(value));
+			atomic_set(&trigger_data->interval, msecs_to_jiffies(value));
+		}
 		set_baseline_state(trigger_data);	/* resets timer */
 	}