aboutsummaryrefslogtreecommitdiff
path: root/drivers/video
diff options
context:
space:
mode:
authorKim, Milo <Milo.Kim@ti.com>2013-02-21 16:44:06 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-21 17:22:25 -0800
commit26e8ccc223ebfd2047a96074f142544dc7062cfe (patch)
tree5bb294732ee8502a139d578d61d1faaae2031618 /drivers/video
parent68853bc2b360c06094477523f7d28efd2d9e3bf3 (diff)
backlight: lp855x_bl: support new LP8557 device
LP8557 is one of LP855x family device, but it has different register map and initialization process. To support this device, device specific configuration is done through the lp855x_device_config structure. Few register definitions are fixed for better readability. BRIGHTNESS_CTRL -> LP855X_BRIGHTNESS_CTRL DEVICE_CTRL -> LP855X_DEVICE_CTRL EEPROM_START -> LP855X_EEPROM_START EEPROM_END -> LP855X_EEPROM_END EPROM_START -> LP8556_EPROM_START EPROM_END -> LP8556_EPROM_END And LP8557 register definitions are added. New register function, lp855x_update_bit() is added. Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Acked-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/video')
-rw-r--r--drivers/video/backlight/Kconfig2
-rw-r--r--drivers/video/backlight/lp855x_bl.c87
2 files changed, 73 insertions, 16 deletions
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index a942a248848..be27b551473 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -381,7 +381,7 @@ config BACKLIGHT_LP855X
tristate "Backlight driver for TI LP855X"
depends on BACKLIGHT_CLASS_DEVICE && I2C
help
- This supports TI LP8550, LP8551, LP8552, LP8553 and LP8556
+ This supports TI LP8550, LP8551, LP8552, LP8553, LP8556 and LP8557
backlight driver.
config BACKLIGHT_OT200
diff --git a/drivers/video/backlight/lp855x_bl.c b/drivers/video/backlight/lp855x_bl.c
index 050cfbb5366..edd2041b152 100644
--- a/drivers/video/backlight/lp855x_bl.c
+++ b/drivers/video/backlight/lp855x_bl.c
@@ -17,13 +17,23 @@
#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"
@@ -75,6 +85,24 @@ 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) {
+ dev_err(lp->dev, "failed to read 0x%.2x\n", reg);
+ return ret;
+ }
+
+ tmp = (u8)ret;
+ tmp &= ~mask;
+ tmp |= data & mask;
+
+ return lp855x_write_byte(lp, reg, tmp);
+}
+
static bool lp855x_is_valid_rom_area(struct lp855x *lp, u8 addr)
{
u8 start, end;
@@ -84,12 +112,16 @@ 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;
@@ -98,9 +130,30 @@ static bool lp855x_is_valid_rom_area(struct lp855x *lp, u8 addr)
return (addr >= start && addr <= end);
}
+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 = BRIGHTNESS_CTRL,
- .reg_devicectrl = DEVICE_CTRL,
+ .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,
};
/*
@@ -123,6 +176,9 @@ static int lp855x_configure(struct lp855x *lp)
case LP8550 ... LP8556:
lp->cfg = &lp855x_dev_cfg;
break;
+ case LP8557:
+ lp->cfg = &lp8557_dev_cfg;
+ break;
default:
return -EINVAL;
}
@@ -210,7 +266,7 @@ 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;
@@ -224,7 +280,7 @@ static int lp855x_bl_get_brightness(struct backlight_device *bl)
if (mode == REGISTER_BASED) {
u8 val = 0;
- lp855x_read_byte(lp, BRIGHTNESS_CTRL, &val);
+ lp855x_read_byte(lp, lp->cfg->reg_brightness, &val);
bl->props.brightness = val;
}
@@ -376,6 +432,7 @@ static const struct i2c_device_id lp855x_ids[] = {
{"lp8552", LP8552},
{"lp8553", LP8553},
{"lp8556", LP8556},
+ {"lp8557", LP8557},
{ }
};
MODULE_DEVICE_TABLE(i2c, lp855x_ids);