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2013-02-22backlight: lp855x_bl: support new LP8557 deviceKim, Milo1-2/+2
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>
2012-12-18drivers/video/backlight/lp855x_bl.c: use generic PWM functionsKim, Milo1-8/+2
The LP855x family devices support the PWM input for the backlight control. Period of the PWM is configurable in the platform side. Platform specific functions are unnecessary anymore because generic PWM functions are used inside the driver. (PWM input mode) To set the brightness, new lp855x_pwm_ctrl() is used. If a PWM device is not allocated, devm_pwm_get() is called. The PWM consumer name is from the chip name such as 'lp8550' and 'lp8556'. To get the brightness value, no additional handling is required. Just the value of 'props.brightness' is returned. If the PWM driver is not ready while initializing the LP855x driver, it's OK. The PWM device can be retrieved later, when the brightness value is changed. Documentation is updated with an example. [akpm@linux-foundation.org: coding-style simplification, per Thierry] Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Cc: Thierry Reding <thierry.reding@avionic-design.de> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Bryan Wu <bryan.wu@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24backlight: new backlight driver for LP855x devicesKim, Milo1-0/+78
THis driver supports TI LP8550/LP8551/LP8552/LP8553/LP8556 backlight devices. The brightness can be controlled by the I2C or PWM input. The lp855x driver provides both modes. For the PWM control, pwm-specific functions can be defined in the platform data. And some information can be read via the sysfs(lp855x device attributes). For details, please refer to Documentation/backlight/lp855x-driver.txt. [axel.lin@gmail.com: add missing mutex_unlock in lp855x_read_byte() error path] [axel.lin@gmail.com: check platform data in lp855x_probe()] [axel.lin@gmail.com: small cleanups] [dan.carpenter@oracle.com: silence a compiler warning] [axel.lin@gmail.com: use id->driver_data to differentiate lp855x chips] [akpm@linux-foundation.org: simplify boolean return expression] Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>