diff options
Diffstat (limited to 'drivers/video/backlight/lp855x_bl.c')
| -rw-r--r-- | drivers/video/backlight/lp855x_bl.c | 169 |
1 files changed, 130 insertions, 39 deletions
diff --git a/drivers/video/backlight/lp855x_bl.c b/drivers/video/backlight/lp855x_bl.c index 6e4db0c874c8..7ae9ae6f4655 100644 --- a/drivers/video/backlight/lp855x_bl.c +++ b/drivers/video/backlight/lp855x_bl.c @@ -17,21 +17,48 @@ #include <linux/platform_data/lp855x.h> #include <linux/pwm.h> -/* Registers */ -#define BRIGHTNESS_CTRL 0x00 -#define DEVICE_CTRL 0x01 -#define EEPROM_START 0xA0 -#define EEPROM_END 0xA7 -#define EPROM_START 0xA0 -#define EPROM_END 0xAF +/* LP8550/1/2/3/6 Registers */ +#define LP855X_BRIGHTNESS_CTRL 0x00 +#define LP855X_DEVICE_CTRL 0x01 +#define LP855X_EEPROM_START 0xA0 +#define LP855X_EEPROM_END 0xA7 +#define LP8556_EPROM_START 0xA0 +#define LP8556_EPROM_END 0xAF + +/* LP8557 Registers */ +#define LP8557_BL_CMD 0x00 +#define LP8557_BL_MASK 0x01 +#define LP8557_BL_ON 0x01 +#define LP8557_BL_OFF 0x00 +#define LP8557_BRIGHTNESS_CTRL 0x04 +#define LP8557_CONFIG 0x10 +#define LP8557_EPROM_START 0x10 +#define LP8557_EPROM_END 0x1E #define BUF_SIZE 20 #define DEFAULT_BL_NAME "lcd-backlight" #define MAX_BRIGHTNESS 255 +struct lp855x; + +/* + * struct lp855x_device_config + * @pre_init_device: init device function call before updating the brightness + * @reg_brightness: register address for brigthenss control + * @reg_devicectrl: register address for device control + * @post_init_device: late init device function call + */ +struct lp855x_device_config { + int (*pre_init_device)(struct lp855x *); + u8 reg_brightness; + u8 reg_devicectrl; + int (*post_init_device)(struct lp855x *); +}; + struct lp855x { const char *chipname; enum lp855x_chip_id chip_id; + struct lp855x_device_config *cfg; struct i2c_client *client; struct backlight_device *bl; struct device *dev; @@ -39,9 +66,15 @@ struct lp855x { struct pwm_device *pwm; }; -static int lp855x_read_byte(struct lp855x *lp, u8 reg, u8 *data) +static int lp855x_write_byte(struct lp855x *lp, u8 reg, u8 data) +{ + return i2c_smbus_write_byte_data(lp->client, reg, data); +} + +static int lp855x_update_bit(struct lp855x *lp, u8 reg, u8 mask, u8 data) { int ret; + u8 tmp; ret = i2c_smbus_read_byte_data(lp->client, reg); if (ret < 0) { @@ -49,13 +82,11 @@ static int lp855x_read_byte(struct lp855x *lp, u8 reg, u8 *data) return ret; } - *data = (u8)ret; - return 0; -} + tmp = (u8)ret; + tmp &= ~mask; + tmp |= data & mask; -static int lp855x_write_byte(struct lp855x *lp, u8 reg, u8 data) -{ - return i2c_smbus_write_byte_data(lp->client, reg, data); + return lp855x_write_byte(lp, reg, tmp); } static bool lp855x_is_valid_rom_area(struct lp855x *lp, u8 addr) @@ -67,12 +98,16 @@ static bool lp855x_is_valid_rom_area(struct lp855x *lp, u8 addr) case LP8551: case LP8552: case LP8553: - start = EEPROM_START; - end = EEPROM_END; + start = LP855X_EEPROM_START; + end = LP855X_EEPROM_END; break; case LP8556: - start = EPROM_START; - end = EPROM_END; + start = LP8556_EPROM_START; + end = LP8556_EPROM_END; + break; + case LP8557: + start = LP8557_EPROM_START; + end = LP8557_EPROM_END; break; default: return false; @@ -81,21 +116,76 @@ static bool lp855x_is_valid_rom_area(struct lp855x *lp, u8 addr) return (addr >= start && addr <= end); } -static int lp855x_init_registers(struct lp855x *lp) +static int lp8557_bl_off(struct lp855x *lp) +{ + /* BL_ON = 0 before updating EPROM settings */ + return lp855x_update_bit(lp, LP8557_BL_CMD, LP8557_BL_MASK, + LP8557_BL_OFF); +} + +static int lp8557_bl_on(struct lp855x *lp) +{ + /* BL_ON = 1 after updating EPROM settings */ + return lp855x_update_bit(lp, LP8557_BL_CMD, LP8557_BL_MASK, + LP8557_BL_ON); +} + +static struct lp855x_device_config lp855x_dev_cfg = { + .reg_brightness = LP855X_BRIGHTNESS_CTRL, + .reg_devicectrl = LP855X_DEVICE_CTRL, +}; + +static struct lp855x_device_config lp8557_dev_cfg = { + .reg_brightness = LP8557_BRIGHTNESS_CTRL, + .reg_devicectrl = LP8557_CONFIG, + .pre_init_device = lp8557_bl_off, + .post_init_device = lp8557_bl_on, +}; + +/* + * Device specific configuration flow + * + * a) pre_init_device(optional) + * b) update the brightness register + * c) update device control register + * d) update ROM area(optional) + * e) post_init_device(optional) + * + */ +static int lp855x_configure(struct lp855x *lp) { u8 val, addr; int i, ret; struct lp855x_platform_data *pd = lp->pdata; + switch (lp->chip_id) { + case LP8550 ... LP8556: + lp->cfg = &lp855x_dev_cfg; + break; + case LP8557: + lp->cfg = &lp8557_dev_cfg; + break; + default: + return -EINVAL; + } + + if (lp->cfg->pre_init_device) { + ret = lp->cfg->pre_init_device(lp); + if (ret) { + dev_err(lp->dev, "pre init device err: %d\n", ret); + goto err; + } + } + val = pd->initial_brightness; - ret = lp855x_write_byte(lp, BRIGHTNESS_CTRL, val); + ret = lp855x_write_byte(lp, lp->cfg->reg_brightness, val); if (ret) - return ret; + goto err; val = pd->device_control; - ret = lp855x_write_byte(lp, DEVICE_CTRL, val); + ret = lp855x_write_byte(lp, lp->cfg->reg_devicectrl, val); if (ret) - return ret; + goto err; if (pd->load_new_rom_data && pd->size_program) { for (i = 0; i < pd->size_program; i++) { @@ -106,10 +196,21 @@ static int lp855x_init_registers(struct lp855x *lp) ret = lp855x_write_byte(lp, addr, val); if (ret) - return ret; + goto err; + } + } + + if (lp->cfg->post_init_device) { + ret = lp->cfg->post_init_device(lp); + if (ret) { + dev_err(lp->dev, "post init device err: %d\n", ret); + goto err; } } + return 0; + +err: return ret; } @@ -151,7 +252,7 @@ static int lp855x_bl_update_status(struct backlight_device *bl) } else if (mode == REGISTER_BASED) { u8 val = bl->props.brightness; - lp855x_write_byte(lp, BRIGHTNESS_CTRL, val); + lp855x_write_byte(lp, lp->cfg->reg_brightness, val); } return 0; @@ -159,16 +260,6 @@ static int lp855x_bl_update_status(struct backlight_device *bl) static int lp855x_bl_get_brightness(struct backlight_device *bl) { - struct lp855x *lp = bl_get_data(bl); - enum lp855x_brightness_ctrl_mode mode = lp->pdata->mode; - - if (mode == REGISTER_BASED) { - u8 val = 0; - - lp855x_read_byte(lp, BRIGHTNESS_CTRL, &val); - bl->props.brightness = val; - } - return bl->props.brightness; } @@ -271,11 +362,10 @@ static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id) lp->chip_id = id->driver_data; i2c_set_clientdata(cl, lp); - ret = lp855x_init_registers(lp); + ret = lp855x_configure(lp); if (ret) { - dev_err(lp->dev, "i2c communication err: %d", ret); - if (mode == REGISTER_BASED) - goto err_dev; + dev_err(lp->dev, "device config err: %d", ret); + goto err_dev; } ret = lp855x_backlight_register(lp); @@ -318,6 +408,7 @@ static const struct i2c_device_id lp855x_ids[] = { {"lp8552", LP8552}, {"lp8553", LP8553}, {"lp8556", LP8556}, + {"lp8557", LP8557}, { } }; MODULE_DEVICE_TABLE(i2c, lp855x_ids); |