openwrtv4/target/linux/brcm2708/patches-4.9/950-0055-BCM270x_DT-Add-pwr_led-and-the-required-input-trigge.patch
Rafał Miłecki fce21ae4cc brcm2708: rename all patches from raspberrypi git tree to use 950 prefix
Right now all brcm2708 patches are extracted from the non-mainline
raspberrypi/linux git tree. Many of them are hacks and/or are unneeded
in LEDE. Raspberry Pi is getting better and better mainline support so
it would be nice to finally start maintaining patches in a cleaner way:
1) Backport patches accepted in upstream tree
2) Start using upstream drivers
3) Pick only these patches that are needed for more complete support

Handling above tasks requires grouping patches - ideally using the same
prefixes as generic ones. It means we should rename existing patches to
use some high prefix. This will allow e.g. use 0xx for backported code.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Stijn Tintel <stijn@linux-ipv6.be>
2017-03-24 08:06:35 +01:00

166 lines
5.6 KiB
Diff

From 766357a4f8476461035dcfe2c6b43f532366f533 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Fri, 6 Feb 2015 13:50:57 +0000
Subject: [PATCH] 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
@@ -50,8 +50,15 @@ static void gpio_led_set(struct led_clas
led_dat->platform_gpio_blink_set(led_dat->gpiod, 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, level);
+ led_dat->cdev.flags &= ~SET_GPIO_OUTPUT;
} else {
- if (led_dat->can_sleep)
+ if (led_dat->can_sleep ||
+ (led_dat->cdev.flags & (SET_GPIO_INPUT | SET_GPIO_OUTPUT) ))
gpiod_set_value_cansleep(led_dat->gpiod, level);
else
gpiod_set_value(led_dat->gpiod, level);
@@ -65,6 +72,13 @@ static int gpio_led_set_blocking(struct
return 0;
}
+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)
{
@@ -122,6 +136,8 @@ static int create_gpio_led(const struct
led_dat->platform_gpio_blink_set = blink_set;
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);
if (state < 0)
--- a/drivers/leds/trigger/Kconfig
+++ b/drivers/leds/trigger/Kconfig
@@ -116,6 +116,13 @@ config LEDS_TRIGGER_CAMERA
This enables direct flash/torch on/off by the driver, kernel space.
If unsure, say Y.
+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.
+
config LEDS_TRIGGER_PANIC
bool "LED Panic Trigger"
depends on LEDS_TRIGGERS
--- a/drivers/leds/trigger/Makefile
+++ b/drivers/leds/trigger/Makefile
@@ -9,4 +9,5 @@ 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-$(CONFIG_LEDS_TRIGGER_INPUT) += ledtrig-input.o
obj-$(CONFIG_LEDS_TRIGGER_PANIC) += ledtrig-panic.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(led_cdev, 0);
+}
+
+static void input_trig_deactivate(struct led_classdev *led_cdev)
+{
+ led_cdev->flags |= SET_GPIO_OUTPUT;
+ led_set_brightness(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
@@ -52,6 +52,9 @@ struct led_classdev {
#define LED_DEV_CAP_FLASH (1 << 24)
#define LED_HW_PLUGGABLE (1 << 25)
#define LED_PANIC_INDICATOR (1 << 26)
+ /* 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 brightness_set_blocking for drivers