diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0073-BCM270x_DT-Add-pwr_led-and-the-required-input-trigge.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.4/0073-BCM270x_DT-Add-pwr_led-and-the-required-input-trigge.patch | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0073-BCM270x_DT-Add-pwr_led-and-the-required-input-trigge.patch b/target/linux/brcm2708/patches-4.4/0073-BCM270x_DT-Add-pwr_led-and-the-required-input-trigge.patch new file mode 100644 index 0000000000..3a26865941 --- /dev/null +++ b/target/linux/brcm2708/patches-4.4/0073-BCM270x_DT-Add-pwr_led-and-the-required-input-trigge.patch @@ -0,0 +1,170 @@ +From 96aac93fdea2caa77d4746aa001c2d792b314112 Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.org> +Date: Fri, 6 Feb 2015 13:50:57 +0000 +Subject: [PATCH 073/232] BCM270x_DT: Add pwr_led, and the required "input" + trigger + +The "input" trigger makes the associated GPIO an input. This is to support +the Raspberry Pi PWR LED, which is driven by external hardware in normal use. + +N.B. pwr_led is not available on Model A or B boards. + +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 | 18 +++++++++++- + drivers/leds/trigger/Kconfig | 7 +++++ + drivers/leds/trigger/Makefile | 1 + + drivers/leds/trigger/ledtrig-input.c | 54 ++++++++++++++++++++++++++++++++++++ + include/linux/leds.h | 3 ++ + 5 files changed, 82 insertions(+), 1 deletion(-) + create mode 100644 drivers/leds/trigger/ledtrig-input.c + +--- a/drivers/leds/leds-gpio.c ++++ b/drivers/leds/leds-gpio.c +@@ -42,6 +42,13 @@ static void gpio_led_work(struct work_st + led_dat->platform_gpio_blink_set(led_dat->gpiod, + led_dat->new_level, NULL, NULL); + led_dat->blinking = 0; ++ } else if (led_dat->cdev.flags & SET_GPIO_INPUT) { ++ gpiod_direction_input(led_dat->gpiod); ++ led_dat->cdev.flags &= ~SET_GPIO_INPUT; ++ } ++ else if (led_dat->cdev.flags & SET_GPIO_OUTPUT) { ++ gpiod_direction_output(led_dat->gpiod, led_dat->new_level); ++ led_dat->cdev.flags &= ~SET_GPIO_OUTPUT; + } else + gpiod_set_value_cansleep(led_dat->gpiod, led_dat->new_level); + } +@@ -62,7 +69,8 @@ static void gpio_led_set(struct led_clas + * seem to have a reliable way to know if we're already in one; so + * let's just assume the worst. + */ +- if (led_dat->can_sleep) { ++ if (led_dat->can_sleep || ++ (led_dat->cdev.flags & (SET_GPIO_INPUT | SET_GPIO_OUTPUT) )) { + led_dat->new_level = level; + schedule_work(&led_dat->work); + } else { +@@ -75,6 +83,13 @@ 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) + { +@@ -131,6 +146,7 @@ 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 +--- a/drivers/leds/trigger/Kconfig ++++ b/drivers/leds/trigger/Kconfig +@@ -126,4 +126,11 @@ config LEDS_TRIGGER_USBDEV + This allows LEDs to be controlled by the presence/activity of + an USB device. If unsure, say N. + ++config LEDS_TRIGGER_INPUT ++ tristate "LED Input Trigger" ++ depends on LEDS_TRIGGERS ++ help ++ This allows the GPIOs assigned to be LEDs to be initialised to inputs. ++ If unsure, say Y. ++ + endif # LEDS_TRIGGERS +--- a/drivers/leds/trigger/Makefile ++++ b/drivers/leds/trigger/Makefile +@@ -8,3 +8,4 @@ obj-$(CONFIG_LEDS_TRIGGER_CPU) += ledtr + obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON) += ledtrig-default-on.o + obj-$(CONFIG_LEDS_TRIGGER_TRANSIENT) += ledtrig-transient.o + obj-$(CONFIG_LEDS_TRIGGER_CAMERA) += ledtrig-camera.o ++obj-$(CONFIG_LEDS_TRIGGER_INPUT) += ledtrig-input.o +--- /dev/null ++++ b/drivers/leds/trigger/ledtrig-input.c +@@ -0,0 +1,54 @@ ++/* ++ * Set LED GPIO to Input "Trigger" ++ * ++ * Copyright 2015 Phil Elwell <phil@raspberrypi.org> ++ * ++ * Based on Nick Forbes's ledtrig-default-on.c. ++ * ++ * This program is free software; you can redistribute it and/or modify ++ * it under the terms of the GNU General Public License version 2 as ++ * published by the Free Software Foundation. ++ * ++ */ ++ ++#include <linux/module.h> ++#include <linux/kernel.h> ++#include <linux/init.h> ++#include <linux/leds.h> ++#include <linux/gpio.h> ++#include "../leds.h" ++ ++static void input_trig_activate(struct led_classdev *led_cdev) ++{ ++ led_cdev->flags |= SET_GPIO_INPUT; ++ led_set_brightness_async(led_cdev, 0); ++} ++ ++static void input_trig_deactivate(struct led_classdev *led_cdev) ++{ ++ led_cdev->flags |= SET_GPIO_OUTPUT; ++ led_set_brightness_async(led_cdev, 0); ++} ++ ++static struct led_trigger input_led_trigger = { ++ .name = "input", ++ .activate = input_trig_activate, ++ .deactivate = input_trig_deactivate, ++}; ++ ++static int __init input_trig_init(void) ++{ ++ return led_trigger_register(&input_led_trigger); ++} ++ ++static void __exit input_trig_exit(void) ++{ ++ led_trigger_unregister(&input_led_trigger); ++} ++ ++module_init(input_trig_init); ++module_exit(input_trig_exit); ++ ++MODULE_AUTHOR("Phil Elwell <phil@raspberrypi.org>"); ++MODULE_DESCRIPTION("Set LED GPIO to Input \"trigger\""); ++MODULE_LICENSE("GPL"); +--- a/include/linux/leds.h ++++ b/include/linux/leds.h +@@ -48,6 +48,9 @@ struct led_classdev { + #define SET_BRIGHTNESS_ASYNC (1 << 21) + #define SET_BRIGHTNESS_SYNC (1 << 22) + #define LED_DEV_CAP_FLASH (1 << 23) ++ /* Additions for Raspberry Pi PWR LED */ ++#define SET_GPIO_INPUT (1 << 30) ++#define SET_GPIO_OUTPUT (1 << 31) + + /* Set LED brightness level */ + /* Must not sleep, use a workqueue if needed */ |