==================== Kernel driver lp855x ==================== Backlight driver for LP855x ICs Supported chips: Texas Instruments LP8550, LP8551, LP8552, LP8553, LP8555, LP8556 and LP8557 Author: Milo(Woogyom) Kim Description ----------- * Brightness control Brightness can be controlled by the pwm input or the i2c command. The lp855x driver supports both cases. * Device attributes 1) bl_ctl_mode Backlight control mode. Value: pwm based or register based 2) chip_id The lp855x chip id. Value: lp8550/lp8551/lp8552/lp8553/lp8555/lp8556/lp8557 Platform data for lp855x ------------------------ For supporting platform specific data, the lp855x platform data can be used. * name: Backlight driver name. If it is not defined, default name is set. * device_control: Value of DEVICE CONTROL register. * initial_brightness: Initial value of backlight brightness. * period_ns: Platform specific PWM period value. unit is nano. Only valid when brightness is pwm input mode. * size_program: Total size of lp855x_rom_data. * rom_data: List of new eeprom/eprom registers. Examples ======== 1) lp8552 platform data: i2c register mode with new eeprom data:: #define EEPROM_A5_ADDR 0xA5 #define EEPROM_A5_VAL 0x4f /* EN_VSYNC=0 */ static struct lp855x_rom_data lp8552_eeprom_arr[] = { {EEPROM_A5_ADDR, EEPROM_A5_VAL}, }; static struct lp855x_platform_data lp8552_pdata = { .name = "lcd-bl", .device_control = I2C_CONFIG(LP8552), .initial_brightness = INITIAL_BRT, .size_program = ARRAY_SIZE(lp8552_eeprom_arr), .rom_data = lp8552_eeprom_arr, }; 2) lp8556 platform data: pwm input mode with default rom data:: static struct lp855x_platform_data lp8556_pdata = { .device_control = PWM_CONFIG(LP8556), .initial_brightness = INITIAL_BRT, .period_ns = 1000000, };