target/linux/brcm2708/patches-4.1/0053-BCM270x_DT-Add-pwr_led-and-the-required-input-trigge.patch

   1 From ade319d70297e1258ae65ff733ae56b6ad51ec96 Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.org>
   3 Date: Fri, 6 Feb 2015 13:50:57 +0000
   4 Subject: [PATCH 053/171] BCM270x_DT: Add pwr_led, and the required "input"
   5  trigger
   6
   7 The "input" trigger makes the associated GPIO an input.  This is to support
   8 the Raspberry Pi PWR LED, which is driven by external hardware in normal use.
   9
  10 N.B. pwr_led is not available on Model A or B boards.
  11 ---
  12  drivers/leds/trigger/Kconfig         |  7 ++++
  13  drivers/leds/trigger/Makefile        |  1 +
  14  drivers/leds/trigger/ledtrig-input.c | 65 ++++++++++++++++++++++++++++++++++++
  15  3 files changed, 73 insertions(+)
  16  create mode 100644 drivers/leds/trigger/ledtrig-input.c
  17
  18 --- a/drivers/leds/trigger/Kconfig
  19 +++ b/drivers/leds/trigger/Kconfig
  20 @@ -126,4 +126,11 @@ config LEDS_TRIGGER_USBDEV
  21           This allows LEDs to be controlled by the presence/activity of
  22           an USB device. If unsure, say N.
  23
  24 +config LEDS_TRIGGER_INPUT
  25 +       tristate "LED Input Trigger"
  26 +       depends on LEDS_TRIGGERS
  27 +       help
  28 +         This allows the GPIOs assigned to be LEDs to be initialised to inputs.
  29 +         If unsure, say Y.
  30 +
  31  endif # LEDS_TRIGGERS
  32 --- a/drivers/leds/trigger/Makefile
  33 +++ b/drivers/leds/trigger/Makefile
  34 @@ -8,3 +8,4 @@ obj-$(CONFIG_LEDS_TRIGGER_CPU)          += ledtr
  35  obj-$(CONFIG_LEDS_TRIGGER_DEFAULT_ON)  += ledtrig-default-on.o
  36  obj-$(CONFIG_LEDS_TRIGGER_TRANSIENT)   += ledtrig-transient.o
  37  obj-$(CONFIG_LEDS_TRIGGER_CAMERA)      += ledtrig-camera.o
  38 +obj-$(CONFIG_LEDS_TRIGGER_INPUT)       += ledtrig-input.o
  39 --- /dev/null
  40 +++ b/drivers/leds/trigger/ledtrig-input.c
  41 @@ -0,0 +1,65 @@
  42 +/*
  43 + * Set LED GPIO to Input "Trigger"
  44 + *
  45 + * Copyright 2015 Phil Elwell <phil@raspberrypi.org>
  46 + *
  47 + * Based on Nick Forbes's ledtrig-default-on.c.
  48 + *
  49 + * This program is free software; you can redistribute it and/or modify
  50 + * it under the terms of the GNU General Public License version 2 as
  51 + * published by the Free Software Foundation.
  52 + *
  53 + */
  54 +
  55 +#include <linux/module.h>
  56 +#include <linux/kernel.h>
  57 +#include <linux/init.h>
  58 +#include <linux/leds.h>
  59 +#include <linux/gpio.h>
  60 +#include "../leds.h"
  61 +
  62 +/* This is a hack to get at the private 'gpio' member */
  63 +
  64 +struct gpio_led_data {
  65 +       struct led_classdev cdev;
  66 +       unsigned gpio;
  67 +};
  68 +
  69 +static void input_trig_activate(struct led_classdev *led_cdev)
  70 +{
  71 +       struct gpio_led_data *led_dat =
  72 +               container_of(led_cdev, struct gpio_led_data, cdev);
  73 +       if (gpio_is_valid(led_dat->gpio))
  74 +               gpio_direction_input(led_dat->gpio);
  75 +}
  76 +
  77 +static void input_trig_deactivate(struct led_classdev *led_cdev)
  78 +{
  79 +       struct gpio_led_data *led_dat =
  80 +               container_of(led_cdev, struct gpio_led_data, cdev);
  81 +       if (gpio_is_valid(led_dat->gpio))
  82 +               gpio_direction_output(led_dat->gpio, 0);
  83 +}
  84 +
  85 +static struct led_trigger input_led_trigger = {
  86 +       .name     = "input",
  87 +       .activate = input_trig_activate,
  88 +       .deactivate = input_trig_deactivate,
  89 +};
  90 +
  91 +static int __init input_trig_init(void)
  92 +{
  93 +       return led_trigger_register(&input_led_trigger);
  94 +}
  95 +
  96 +static void __exit input_trig_exit(void)
  97 +{
  98 +       led_trigger_unregister(&input_led_trigger);
  99 +}
 100 +
 101 +module_init(input_trig_init);
 102 +module_exit(input_trig_exit);
 103 +
 104 +MODULE_AUTHOR("Phil Elwell <phil@raspberrypi.org>");
 105 +MODULE_DESCRIPTION("Set LED GPIO to Input \"trigger\"");
 106 +MODULE_LICENSE("GPL");