leds: gpio: Allow LED to retain state at shutdown
In some systems, such as Baseboard Management Controllers (BMCs), we
want to retain the state of LEDs across a reboot of the BMC (whilst the
host remains up). Implement support for the retain-state-shutdown
devicetree property in leds-gpio.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Brandon Wyman <bjwyman@gmail.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
diff --git a/include/linux/leds.h b/include/linux/leds.h
index 64c56d4..bf6db4f 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -49,6 +49,7 @@ struct led_classdev {
#define LED_HW_PLUGGABLE (1 << 19)
#define LED_PANIC_INDICATOR (1 << 20)
#define LED_BRIGHT_HW_CHANGED (1 << 21)
+#define LED_RETAIN_AT_SHUTDOWN (1 << 22)
/* set_brightness_work / blink_timer flags, atomic, private. */
unsigned long work_flags;
@@ -392,6 +393,7 @@ struct gpio_led {
unsigned retain_state_suspended : 1;
unsigned panic_indicator : 1;
unsigned default_state : 2;
+ unsigned retain_state_shutdown : 1;
/* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
struct gpio_desc *gpiod;
};