projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 7be865ab KM |
1 | Kernel driver lp855x |
| 2 | ==================== | |
| 3 | ||
| 4 | Backlight driver for LP855x ICs | |
| 5 | ||
| 6 | Supported chips: | |
| 7 | Texas Instruments LP8550, LP8551, LP8552, LP8553 and LP8556 | |
| 8 | ||
| 9 | Author: Milo(Woogyom) Kim <milo.kim@ti.com> | |
| 10 | ||
| 11 | Description | |
| 12 | ----------- | |
| 13 | ||
| 14 | * Brightness control | |
| 15 | ||
| 16 | Brightness can be controlled by the pwm input or the i2c command. | |
| 17 | The lp855x driver supports both cases. | |
| 18 | ||
| 19 | * Device attributes | |
| 20 | ||
| 21 | 1) bl_ctl_mode | |
| 22 | Backlight control mode. | |
| 23 | Value : pwm based or register based | |
| 24 | ||
| 25 | 2) chip_id | |
| 26 | The lp855x chip id. | |
| 27 | Value : lp8550/lp8551/lp8552/lp8553/lp8556 | |
| 28 | ||
| 29 | Platform data for lp855x | |
| 30 | ------------------------ | |
| 31 | ||
| 32 | For supporting platform specific data, the lp855x platform data can be used. | |
| 33 | ||
| 34 | * name : Backlight driver name. If it is not defined, default name is set. | |
| 35 | * mode : Brightness control mode. PWM or register based. | |
| 36 | * device_control : Value of DEVICE CONTROL register. | |
| 37 | * initial_brightness : Initial value of backlight brightness. | |
| 8cc9764c | 38 | * period_ns : Platform specific PWM period value. unit is nano. |
| 7be865ab | 39 | Only valid when brightness is pwm input mode. |
| 7be865ab KM |
40 | * load_new_rom_data : |
| 41 | 0 : use default configuration data | |
| 42 | 1 : update values of eeprom or eprom registers on loading driver | |
| 43 | * size_program : Total size of lp855x_rom_data. | |
| 44 | * rom_data : List of new eeprom/eprom registers. | |
| 45 | ||
| 46 | example 1) lp8552 platform data : i2c register mode with new eeprom data | |
| 47 | ||
| 48 | #define EEPROM_A5_ADDR 0xA5 | |
| 49 | #define EEPROM_A5_VAL 0x4f /* EN_VSYNC=0 */ | |
| 50 | ||
| 51 | static struct lp855x_rom_data lp8552_eeprom_arr[] = { | |
| 52 | {EEPROM_A5_ADDR, EEPROM_A5_VAL}, | |
| 53 | }; | |
| 54 | ||
| 55 | static struct lp855x_platform_data lp8552_pdata = { | |
| 56 | .name = "lcd-bl", | |
| 57 | .mode = REGISTER_BASED, | |
| 58 | .device_control = I2C_CONFIG(LP8552), | |
| 59 | .initial_brightness = INITIAL_BRT, | |
| 60 | .load_new_rom_data = 1, | |
| 61 | .size_program = ARRAY_SIZE(lp8552_eeprom_arr), | |
| 62 | .rom_data = lp8552_eeprom_arr, | |
| 63 | }; | |
| 64 | ||
| 65 | example 2) lp8556 platform data : pwm input mode with default rom data | |
| 66 | ||
| 67 | static struct lp855x_platform_data lp8556_pdata = { | |
| 68 | .mode = PWM_BASED, | |
| 69 | .device_control = PWM_CONFIG(LP8556), | |
| 70 | .initial_brightness = INITIAL_BRT, | |
| 8cc9764c | 71 | .period_ns = 1000000, |
| 7be865ab | 72 | }; |