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/*
* 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/device.h>
#include <linux/kernfs.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/rwsem.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
struct device;
/*
* LED Core
*/
enum led_brightness {
LED_OFF = 0,
LED_ON = 1,
LED_HALF = 127,
LED_FULL = 255,
};
struct led_classdev {
const char *name;
enum led_brightness brightness;
enum led_brightness max_brightness;
int flags;
/* Lower 16 bits reflect status */
#define LED_SUSPENDED BIT(0)
#define LED_UNREGISTERING BIT(1)
/* Upper 16 bits reflect control information */
#define LED_CORE_SUSPENDRESUME BIT(16)
#define LED_SYSFS_DISABLE BIT(17)
#define LED_DEV_CAP_FLASH BIT(18)
#define LED_HW_PLUGGABLE BIT(19)
#define LED_PANIC_INDICATOR BIT(20)
#define LED_BRIGHT_HW_CHANGED BIT(21)
#define LED_RETAIN_AT_SHUTDOWN BIT(22)
/* set_brightness_work / blink_timer flags, atomic, private. */
unsigned long work_flags;
#define LED_BLINK_SW 0
#define LED_BLINK_ONESHOT 1
#define LED_BLINK_ONESHOT_STOP 2
#define LED_BLINK_INVERT 3
#define LED_BLINK_BRIGHTNESS_CHANGE 4
#define LED_BLINK_DISABLE 5
/* Set LED brightness level
* Must not sleep. Use brightness_set_blocking for drivers
* that can sleep while setting brightness.
*/
void (*brightness_set)(struct led_classdev *led_cdev,
enum led_brightness brightness);
/*
* Set LED brightness level immediately - it can block the caller for
* the time required for accessing a LED device register.
*/
int (*brightness_set_blocking)(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, delays are in milliseconds
* and if both are zero then a sensible default should be chosen.
* The call should adjust the timings in that case and if it can't
* match the values specified exactly.
* Deactivate blinking again when the brightness is set to LED_OFF
* via the brightness_set() callback.
*/
int (*blink_set)(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off);
struct device *dev;
const struct attribute_group **groups;
struct list_head node; /* LED Device list */
const char *default_trigger; /* Trigger to use */
unsigned long blink_delay_on, blink_delay_off;
struct timer_list blink_timer;
int blink_brightness;
int new_blink_brightness;
void (*flash_resume)(struct led_classdev *led_cdev);
struct work_struct set_brightness_work;
int delayed_set_value;
#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;
/* true if activated - deactivate routine uses it to do cleanup */
bool activated;
#endif
#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
int brightness_hw_changed;
struct kernfs_node *brightness_hw_changed_kn;
#endif
/* Ensures consistent access to the LED Flash Class device */
struct mutex led_access;
};
extern int of_led_classdev_register(struct device *parent,
struct device_node *np,
struct led_classdev *led_cdev);
#define led_classdev_register(parent, led_cdev) \
of_led_classdev_register(parent, NULL, led_cdev)
extern int devm_of_led_classdev_register(struct device *parent,
struct device_node *np,
struct led_classdev *led_cdev);
#define devm_led_classdev_register(parent, led_cdev) \
devm_of_led_classdev_register(parent, NULL, led_cdev)
extern void led_classdev_unregister(struct led_classdev *led_cdev);
extern void devm_led_classdev_unregister(struct device *parent,
struct led_classdev *led_cdev);
extern void led_classdev_suspend(struct led_classdev *led_cdev);
extern void led_classdev_resume(struct led_classdev *led_cdev);
/**
* led_blink_set - set blinking with software fallback
* @led_cdev: the LED to start blinking
* @delay_on: the time it should be on (in ms)
* @delay_off: the time it should ble off (in ms)
*
* This function makes the LED blink, attempting to use the
* hardware acceleration if possible, but falling back to
* software blinking if there is no hardware blinking or if
* the LED refuses the passed values.
*
* Note that if software blinking is active, simply calling
* led_cdev->brightness_set() will not stop the blinking,
* use led_classdev_brightness_set() instead.
*/
extern void led_blink_set(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off);
/**
* led_blink_set_oneshot - do a oneshot software blink
* @led_cdev: the LED to start blinking
* @delay_on: the time it should be on (in ms)
* @delay_off: the time it should ble off (in ms)
* @invert: blink off, then on, leaving the led on
*
* This function makes the LED blink one time for delay_on +
* delay_off time, ignoring the request if another one-shot
* blink is already in progress.
*
* If invert is set, led blinks for delay_off first, then for
* delay_on and leave the led on after the on-off cycle.
*/
extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off,
int invert);
/**
* led_set_brightness - set LED brightness
* @led_cdev: the LED to set
* @brightness: the brightness to set it to
*
* Set an LED's brightness, and, if necessary, cancel the
* software blink timer that implements blinking when the
* hardware doesn't. This function is guaranteed not to sleep.
*/
extern void led_set_brightness(struct led_classdev *led_cdev,
enum led_brightness brightness);
/**
* led_set_brightness_sync - set LED brightness synchronously
* @led_cdev: the LED to set
* @brightness: the brightness to set it to
*
* Set an LED's brightness immediately. This function will block
* the caller for the time required for accessing device registers,
* and it can sleep.
*
* Returns: 0 on success or negative error value on failure
*/
extern int led_set_brightness_sync(struct led_classdev *led_cdev,
enum led_brightness value);
/**
* led_update_brightness - update LED brightness
* @led_cdev: the LED to query
*
* Get an LED's current brightness and update led_cdev->brightness
* member with the obtained value.
*
* Returns: 0 on success or negative error value on failure
*/
extern int led_update_brightness(struct led_classdev *led_cdev);
/**
* led_sysfs_disable - disable LED sysfs interface
* @led_cdev: the LED to set
*
* Disable the led_cdev's sysfs interface.
*/
extern void led_sysfs_disable(struct led_classdev *led_cdev);
/**
* led_sysfs_enable - enable LED sysfs interface
* @led_cdev: the LED to set
*
* Enable the led_cdev's sysfs interface.
*/
extern void led_sysfs_enable(struct led_classdev *led_cdev);
/**
* led_sysfs_is_disabled - check if LED sysfs interface is disabled
* @led_cdev: the LED to query
*
* Returns: true if the led_cdev's sysfs interface is disabled.
*/
static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev)
{
return led_cdev->flags & LED_SYSFS_DISABLE;
}
/*
* LED Triggers
*/
/* 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;
#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;
};
ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count);
ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr,
char *buf);
/* Registration functions for complex triggers */
extern int led_trigger_register(struct led_trigger *trigger);
extern void led_trigger_unregister(struct led_trigger *trigger);
extern int devm_led_trigger_register(struct device *dev,
struct led_trigger *trigger);
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);
extern void led_trigger_blink(struct led_trigger *trigger,
unsigned long *delay_on,
unsigned long *delay_off);
extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
unsigned long *delay_on,
unsigned long *delay_off,
int invert);
extern void led_trigger_set_default(struct led_classdev *led_cdev);
extern void led_trigger_set(struct led_classdev *led_cdev,
struct led_trigger *trigger);
extern void led_trigger_remove(struct led_classdev *led_cdev);
static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
{
return led_cdev->trigger_data;
}
/**
* led_trigger_rename_static - rename a trigger
* @name: the new trigger name
* @trig: the LED trigger to rename
*
* Change a LED trigger name by copying the string passed in
* name into current trigger name, which MUST be large
* enough for the new string.
*
* Note that name must NOT point to the same string used
* during LED registration, as that could lead to races.
*
* This is meant to be used on triggers with statically
* allocated name.
*/
extern void led_trigger_rename_static(const char *name,
struct led_trigger *trig);
#else
/* Trigger has no members */
struct led_trigger {};
/* Trigger inline empty functions */
static inline void led_trigger_register_simple(const char *name,
struct led_trigger **trigger) {}
static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
static inline void led_trigger_event(struct led_trigger *trigger,
enum led_brightness event) {}
static inline void led_trigger_blink(struct led_trigger *trigger,
unsigned long *delay_on,
unsigned long *delay_off) {}
static inline void led_trigger_blink_oneshot(struct led_trigger *trigger,
unsigned long *delay_on,
unsigned long *delay_off,
int invert) {}
static inline void led_trigger_set_default(struct led_classdev *led_cdev) {}
static inline void led_trigger_set(struct led_classdev *led_cdev,
struct led_trigger *trigger) {}
static inline void led_trigger_remove(struct led_classdev *led_cdev) {}
static inline void *led_get_trigger_data(struct led_classdev *led_cdev)
{
return NULL;
}
#endif /* CONFIG_LEDS_TRIGGERS */
/* Trigger specific functions */
#ifdef CONFIG_LEDS_TRIGGER_DISK
extern void ledtrig_disk_activity(void);
#else
static inline void ledtrig_disk_activity(void) {}
#endif
#ifdef CONFIG_LEDS_TRIGGER_MTD
extern void ledtrig_mtd_activity(void);
#else
static inline void ledtrig_mtd_activity(void) {}
#endif
#if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
extern void ledtrig_flash_ctrl(bool on);
extern void ledtrig_torch_ctrl(bool on);
#else
static inline void ledtrig_flash_ctrl(bool on) {}
static inline void ledtrig_torch_ctrl(bool on) {}
#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;
};
struct gpio_desc;
typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state,
unsigned long *delay_on,
unsigned long *delay_off);
/* For the leds-gpio driver */
struct gpio_led {
const char *name;
const char *default_trigger;
unsigned gpio;
unsigned active_low : 1;
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;
};
#define LEDS_GPIO_DEFSTATE_OFF 0
#define LEDS_GPIO_DEFSTATE_ON 1
#define LEDS_GPIO_DEFSTATE_KEEP 2
struct gpio_led_platform_data {
int num_leds;
const struct gpio_led *leds;
#define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
#define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
#define GPIO_LED_BLINK 2 /* Please, blink */
gpio_blink_set_t gpio_blink_set;
};
#ifdef CONFIG_NEW_LEDS
struct platform_device *gpio_led_register_device(
int id, const struct gpio_led_platform_data *pdata);
#else
static inline struct platform_device *gpio_led_register_device(
int id, const struct gpio_led_platform_data *pdata)
{
return 0;
}
#endif
enum cpu_led_event {
CPU_LED_IDLE_START, /* CPU enters idle */
CPU_LED_IDLE_END, /* CPU idle ends */
CPU_LED_START, /* Machine starts, especially resume */
CPU_LED_STOP, /* Machine stops, especially suspend */
CPU_LED_HALTED, /* Machine shutdown */
};
#ifdef CONFIG_LEDS_TRIGGER_CPU
extern void ledtrig_cpu(enum cpu_led_event evt);
#else
static inline void ledtrig_cpu(enum cpu_led_event evt)
{
return;
}
#endif
#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
extern void led_classdev_notify_brightness_hw_changed(
struct led_classdev *led_cdev, enum led_brightness brightness);
#else
static inline void led_classdev_notify_brightness_hw_changed(
struct led_classdev *led_cdev, enum led_brightness brightness) { }
#endif
#endif /* __LINUX_LEDS_H_INCLUDED */
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