1 /* 2 * LCD Lowlevel Control Abstraction 3 * 4 * Copyright (C) 2003,2004 Hewlett-Packard Company 5 * 6 */ 7 8 #ifndef _LINUX_LCD_H 9 #define _LINUX_LCD_H 10 11 #include <linux/device.h> 12 #include <linux/notifier.h> 13 14 struct lcd_device; 15 struct fb_info; 16 17 /* This structure defines all the properties of a LCD flat panel. */ 18 struct lcd_properties { 19 /* Get the LCD panel power status (0: full on, 1..3: controller 20 power on, flat panel power off, 4: full off), see FB_BLANK_XXX */ 21 int (*get_power)(struct lcd_device *); 22 /* Enable or disable power to the LCD (0: on; 4: off, see FB_BLANK_XXX) */ 23 int (*set_power)(struct lcd_device *, int power); 24 /* The maximum value for contrast (read-only) */ 25 int max_contrast; 26 /* Get the current contrast setting (0-max_contrast) */ 27 int (*get_contrast)(struct lcd_device *); 28 /* Set LCD panel contrast */ 29 int (*set_contrast)(struct lcd_device *, int contrast); 30 /* Check if given framebuffer device is the one LCD is bound to; 31 return 0 if not, !=0 if it is. If NULL, lcd always matches the fb. */ 32 int (*check_fb)(struct fb_info *); 33 }; 34 35 struct lcd_device { 36 /* This protects the 'props' field. If 'props' is NULL, the driver that 37 registered this device has been unloaded, and if class_get_devdata() 38 points to something in the body of that driver, it is also invalid. */ 39 struct semaphore sem; 40 /* If this is NULL, the backing module is unloaded */ 41 struct lcd_properties *props; 42 /* The framebuffer notifier block */ 43 struct notifier_block fb_notif; 44 /* The class device structure */ 45 struct class_device class_dev; 46 }; 47 48 extern struct lcd_device *lcd_device_register(const char *name, 49 void *devdata, struct lcd_properties *lp); 50 extern void lcd_device_unregister(struct lcd_device *ld); 51 52 #define to_lcd_device(obj) container_of(obj, struct lcd_device, class_dev) 53 54 #endif 55