remarkable-linux/include/linux/leds.h
Trent Piepho 326bb8a5a1 leds: Make default trigger fields const
The default_trigger fields of struct gpio_led and thus struct
led_classdev are pretty much always assigned from a string literal,
which means the string can't be modified.  Which is fine, since there is
no reason to modify the string and in fact it never is.

But they should be marked const to prevent such code from being added,
to prevent warnings if -Wwrite-strings is used, when assigned from a
constant string other than a string literal (which produces a warning
under current kernel compiler flags), and for general good coding
practices.

Signed-off-by: Trent Piepho <tpiepho@freescale.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2008-10-20 22:34:12 +01:00

153 lines
3.8 KiB
C

/*
* Driver model for leds and led triggers
*
* Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
* Copyright (C) 2005 Richard Purdie <rpurdie@openedhand.com>
*
* 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.
*
*/
#ifndef __LINUX_LEDS_H_INCLUDED
#define __LINUX_LEDS_H_INCLUDED
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/rwsem.h>
struct device;
/*
* LED Core
*/
enum led_brightness {
LED_OFF = 0,
LED_HALF = 127,
LED_FULL = 255,
};
struct led_classdev {
const char *name;
int brightness;
int flags;
#define LED_SUSPENDED (1 << 0)
/* Set LED brightness level */
/* Must not sleep, use a workqueue if needed */
void (*brightness_set)(struct led_classdev *led_cdev,
enum led_brightness brightness);
/* Get LED brightness level */
enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
/* Activate hardware accelerated blink */
int (*blink_set)(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off);
struct device *dev;
struct list_head node; /* LED Device list */
const char *default_trigger; /* Trigger to use */
#ifdef CONFIG_LEDS_TRIGGERS
/* Protects the trigger data below */
struct rw_semaphore trigger_lock;
struct led_trigger *trigger;
struct list_head trig_list;
void *trigger_data;
#endif
};
extern int led_classdev_register(struct device *parent,
struct led_classdev *led_cdev);
extern void led_classdev_unregister(struct led_classdev *lcd);
extern void led_classdev_suspend(struct led_classdev *led_cdev);
extern void led_classdev_resume(struct led_classdev *led_cdev);
/*
* LED Triggers
*/
#ifdef CONFIG_LEDS_TRIGGERS
#define TRIG_NAME_MAX 50
struct led_trigger {
/* Trigger Properties */
const char *name;
void (*activate)(struct led_classdev *led_cdev);
void (*deactivate)(struct led_classdev *led_cdev);
/* LEDs under control by this trigger (for simple triggers) */
rwlock_t leddev_list_lock;
struct list_head led_cdevs;
/* Link to next registered trigger */
struct list_head next_trig;
};
/* Registration functions for complex triggers */
extern int led_trigger_register(struct led_trigger *trigger);
extern void led_trigger_unregister(struct led_trigger *trigger);
/* Registration functions for simple triggers */
#define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
#define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
extern void led_trigger_register_simple(const char *name,
struct led_trigger **trigger);
extern void led_trigger_unregister_simple(struct led_trigger *trigger);
extern void led_trigger_event(struct led_trigger *trigger,
enum led_brightness event);
#else
/* Triggers aren't active - null macros */
#define DEFINE_LED_TRIGGER(x)
#define DEFINE_LED_TRIGGER_GLOBAL(x)
#define led_trigger_register_simple(x, y) do {} while(0)
#define led_trigger_unregister_simple(x) do {} while(0)
#define led_trigger_event(x, y) do {} while(0)
#endif
/* Trigger specific functions */
#ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
extern void ledtrig_ide_activity(void);
#else
#define ledtrig_ide_activity() do {} while(0)
#endif
/*
* Generic LED platform data for describing LED names and default triggers.
*/
struct led_info {
const char *name;
const char *default_trigger;
int flags;
};
struct led_platform_data {
int num_leds;
struct led_info *leds;
};
/* For the leds-gpio driver */
struct gpio_led {
const char *name;
const char *default_trigger;
unsigned gpio;
u8 active_low;
};
struct gpio_led_platform_data {
int num_leds;
struct gpio_led *leds;
int (*gpio_blink_set)(unsigned gpio,
unsigned long *delay_on,
unsigned long *delay_off);
};
#endif /* __LINUX_LEDS_H_INCLUDED */