Commit 7c145a34 authored by Christian Marangi's avatar Christian Marangi Committed by David S. Miller
Browse files

leds: trigger: netdev: add support for LED hw control 



Add support for LED hw control for the netdev trigger.

The trigger on calling set_baseline_state to configure a new mode, will
do various check to verify if hw control can be used for the requested
mode in can_hw_control() function.

It will first check if the LED driver supports hw control for the netdev
trigger, then will use hw_control_is_supported() and finally will call
hw_control_set() to apply the requested mode.

To use such mode, interval MUST be set to the default value and net_dev
MUST be set. If one of these 2 value are not valid, hw control will
never be used and normal software fallback is used.

The default interval value is moved to a define to make sure they are
always synced.

Signed-off-by: default avatarChristian Marangi <ansuelsmth@gmail.com>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c84c80c7

drivers/leds/trigger/ledtrig-netdev.c

+41 −2
Original line number Diff line number Diff line
@@ -24,6 +24,8 @@ 
#include <linux/timer.h>

#include "../leds.h"



#define NETDEV_LED_DEFAULT_INTERVAL	50



/*

 * Configurable sysfs attributes:

 *
@@ -68,6 +70,13 @@ static void set_baseline_state(struct led_netdev_data *trigger_data) 
	int current_brightness;

	struct led_classdev *led_cdev = trigger_data->led_cdev;



	/* 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);



		return;

	}



	current_brightness = led_cdev->brightness;

	if (current_brightness)

		led_cdev->blink_brightness = current_brightness;
@@ -103,12 +112,42 @@ static bool supports_hw_control(struct led_classdev *led_cdev) 


static bool can_hw_control(struct led_netdev_data *trigger_data)

{

	unsigned long default_interval = msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL);

	unsigned int interval = atomic_read(&trigger_data->interval);

	struct led_classdev *led_cdev = trigger_data->led_cdev;

	int ret;



	if (!supports_hw_control(led_cdev))

		return false;



	/*

	 * Interval must be set to the default

	 * value. Any different value is rejected if in hw

	 * control.

	 */

	if (interval != default_interval)

		return false;



	/*

	 * net_dev must be set with hw control, otherwise no

	 * blinking can be happening and there is nothing to

	 * offloaded.

	 */

	if (!trigger_data->net_dev)

		return false;



	/* Check if the requested mode is supported */

	ret = led_cdev->hw_control_is_supported(led_cdev, trigger_data->mode);

	/* Fall back to software blinking if not supported */

	if (ret == -EOPNOTSUPP)

		return false;

	if (ret) {

		dev_warn(led_cdev->dev,

			 "Current mode check failed with error %d\n", ret);

		return false;

	}



	return true;

}



static ssize_t device_name_show(struct device *dev,
@@ -413,7 +452,7 @@ static int netdev_trig_activate(struct led_classdev *led_cdev) 
	trigger_data->device_name[0] = 0;



	trigger_data->mode = 0;

	atomic_set(&trigger_data->interval, msecs_to_jiffies(50));

	atomic_set(&trigger_data->interval, msecs_to_jiffies(NETDEV_LED_DEFAULT_INTERVAL));

	trigger_data->last_activity = 0;



	led_set_trigger_data(led_cdev, trigger_data);