Edit File: lcd.h
/* * 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) * and this callback would be called proir to fb driver's callback. * * P.S. note that if early_set_power is not NULL then early fb notifier * would be registered. */ int (*early_set_power)(struct lcd_device *, int power); /* revert the effects of the early blank event. */ int (*r_early_set_power)(struct lcd_device *, int power); /* 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 void lcd_device_unregister(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