|
|
|
|
From 5a3324e4eb8898d293fdc562117877cb313718a1 Mon Sep 17 00:00:00 2001
|
|
|
|
|
From: Phil Elwell <phil@raspberrypi.org>
|
|
|
|
|
Date: Wed, 15 Jul 2015 13:46:08 +0100
|
|
|
|
|
Subject: [PATCH 123/203] leds-gpio: Implement the brightness_get method
|
|
|
|
|
|
|
|
|
|
The power LED uses some clever logic that means it is driven
|
|
|
|
|
by a voltage measuring circuit when configured as input, otherwise
|
|
|
|
|
it is driven by the GPIO output value. This patch wires up the
|
|
|
|
|
brightness_get method for leds-gpio so that user-space can monitor
|
|
|
|
|
the LED value via /sys/class/gpio/led1/brightness. Using the input
|
|
|
|
|
trigger this returns an indication of the system power health,
|
|
|
|
|
otherwise it is just whatever value the trigger has written most
|
|
|
|
|
recently.
|
|
|
|
|
|
|
|
|
|
See: https://github.com/raspberrypi/linux/issues/1064
|
|
|
|
|
---
|
|
|
|
|
drivers/leds/leds-gpio.c | 8 ++++++++
|
|
|
|
|
1 file changed, 8 insertions(+)
|
|
|
|
|
|
|
|
|
|
--- a/drivers/leds/leds-gpio.c
|
|
|
|
|
+++ b/drivers/leds/leds-gpio.c
|
|
|
|
|
@@ -82,6 +82,13 @@ static void gpio_led_set(struct led_clas
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
+static enum led_brightness gpio_led_get(struct led_classdev *led_cdev)
|
|
|
|
|
+{
|
|
|
|
|
+ struct gpio_led_data *led_dat =
|
|
|
|
|
+ container_of(led_cdev, struct gpio_led_data, cdev);
|
|
|
|
|
+ return gpiod_get_value_cansleep(led_dat->gpiod) ? LED_FULL : LED_OFF;
|
|
|
|
|
+}
|
|
|
|
|
+
|
|
|
|
|
static int gpio_blink_set(struct led_classdev *led_cdev,
|
|
|
|
|
unsigned long *delay_on, unsigned long *delay_off)
|
|
|
|
|
{
|
|
|
|
|
@@ -138,6 +145,7 @@ static int create_gpio_led(const struct
|
|
|
|
|
led_dat->cdev.blink_set = gpio_blink_set;
|
|
|
|
|
}
|
|
|
|
|
led_dat->cdev.brightness_set = gpio_led_set;
|
|
|
|
|
+ led_dat->cdev.brightness_get = gpio_led_get;
|
|
|
|
|
if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP)
|
|
|
|
|
state = !!gpiod_get_value_cansleep(led_dat->gpiod);
|
|
|
|
|
else
|
