/* SPDX-License-Identifier: GPL-2.0 */
|
/*
|
* LCD Lowlevel Control Abstraction
|
*
|
* Copyright (C) 2003,2004 Hewlett-Packard Company
|
*
|
*/
|
|
#ifndef _LINUX_LCD_H
|
#define _LINUX_LCD_H
|
|
#include <linux/device.h>
|
#include <linux/mutex.h>
|
#include <linux/notifier.h>
|
#include <linux/fb.h>
|
|
/* Notes on locking:
|
*
|
* lcd_device->ops_lock is an internal backlight lock protecting the ops
|
* field and no code outside the core should need to touch it.
|
*
|
* Access to set_power() is serialised by the update_lock mutex since
|
* most drivers seem to need this and historically get it wrong.
|
*
|
* Most drivers don't need locking on their get_power() method.
|
* If yours does, you need to implement it in the driver. You can use the
|
* update_lock mutex if appropriate.
|
*
|
* Any other use of the locks below is probably wrong.
|
*/
|
|
struct lcd_device;
|
struct fb_info;
|
|
struct lcd_properties {
|
/* The maximum value for contrast (read-only) */
|
int max_contrast;
|
};
|
|
struct lcd_ops {
|
/* Get the LCD panel power status (0: full on, 1..3: controller
|
power on, flat panel power off, 4: full off), see FB_BLANK_XXX */
|
int (*get_power)(struct lcd_device *);
|
/* Enable or disable power to the LCD (0: on; 4: off, see FB_BLANK_XXX) */
|
int (*set_power)(struct lcd_device *, int power);
|
/* Get the current contrast setting (0-max_contrast) */
|
int (*get_contrast)(struct lcd_device *);
|
/* Set LCD panel contrast */
|
int (*set_contrast)(struct lcd_device *, int contrast);
|
/* Set LCD panel mode (resolutions ...) */
|
int (*set_mode)(struct lcd_device *, struct fb_videomode *);
|
/* Check if given framebuffer device is the one LCD is bound to;
|
return 0 if not, !=0 if it is. If NULL, lcd always matches the fb. */
|
int (*check_fb)(struct lcd_device *, struct fb_info *);
|
};
|
|
struct lcd_device {
|
struct lcd_properties props;
|
/* This protects the 'ops' field. If 'ops' is NULL, the driver that
|
registered this device has been unloaded, and if class_get_devdata()
|
points to something in the body of that driver, it is also invalid. */
|
struct mutex ops_lock;
|
/* If this is NULL, the backing module is unloaded */
|
struct lcd_ops *ops;
|
/* Serialise access to set_power method */
|
struct mutex update_lock;
|
/* The framebuffer notifier block */
|
struct notifier_block fb_notif;
|
|
struct device dev;
|
};
|
|
struct lcd_platform_data {
|
/* reset lcd panel device. */
|
int (*reset)(struct lcd_device *ld);
|
/* on or off to lcd panel. if 'enable' is 0 then
|
lcd power off and 1, lcd power on. */
|
int (*power_on)(struct lcd_device *ld, int enable);
|
|
/* it indicates whether lcd panel was enabled
|
from bootloader or not. */
|
int lcd_enabled;
|
/* it means delay for stable time when it becomes low to high
|
or high to low that is dependent on whether reset gpio is
|
low active or high active. */
|
unsigned int reset_delay;
|
/* stable time needing to become lcd power on. */
|
unsigned int power_on_delay;
|
/* stable time needing to become lcd power off. */
|
unsigned int power_off_delay;
|
|
/* it could be used for any purpose. */
|
void *pdata;
|
};
|
|
static inline void lcd_set_power(struct lcd_device *ld, int power)
|
{
|
mutex_lock(&ld->update_lock);
|
if (ld->ops && ld->ops->set_power)
|
ld->ops->set_power(ld, power);
|
mutex_unlock(&ld->update_lock);
|
}
|
|
extern struct lcd_device *lcd_device_register(const char *name,
|
struct device *parent, void *devdata, struct lcd_ops *ops);
|
extern struct lcd_device *devm_lcd_device_register(struct device *dev,
|
const char *name, struct device *parent,
|
void *devdata, struct lcd_ops *ops);
|
extern void lcd_device_unregister(struct lcd_device *ld);
|
extern void devm_lcd_device_unregister(struct device *dev,
|
struct lcd_device *ld);
|
|
#define to_lcd_device(obj) container_of(obj, struct lcd_device, dev)
|
|
static inline void * lcd_get_data(struct lcd_device *ld_dev)
|
{
|
return dev_get_drvdata(&ld_dev->dev);
|
}
|
|
|
#endif
|
