docs: lp855x-driver.txt: convert to ReST and move to kernel-api

This small file seems to be an attempt to start documenting
backlight drivers.

It contains descriptions of the controls for the driver
with could sound as an somewhat user-faced description, but
it's main focus is to describe, instead, the data that should
be passed via platform data and some driver-specific stuff.

While this is not part of the driver-api book, mark it as
:orphan:, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

3 files changed, 84 insertions, 67 deletions

diff --git a/Documentation/backlight/lp855x-driver.rst b/Documentation/backlight/lp855x-driver.rst
new file mode 100644
index 000000000000..62b7ed847a77
--- /dev/null
+++ b/Documentation/backlight/lp855x-driver.rst
@@ -0,0 +1,83 @@
+:orphan:
+
+====================
+Kernel driver lp855x
+====================
+
+Backlight driver for LP855x ICs
+
+Supported chips:
+
+	Texas Instruments LP8550, LP8551, LP8552, LP8553, LP8555, LP8556 and
+	LP8557
+
+Author: Milo(Woogyom) Kim <milo.kim@ti.com>
+
+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,
+    };
diff --git a/Documentation/backlight/lp855x-driver.txt b/Documentation/backlight/lp855x-driver.txt
deleted file mode 100644
index 01bce243d3d7..000000000000
--- a/Documentation/backlight/lp855x-driver.txt
+++ /dev/null
@@ -1,66 +0,0 @@
-Kernel driver lp855x
-====================
-
-Backlight driver for LP855x ICs
-
-Supported chips:
-	Texas Instruments LP8550, LP8551, LP8552, LP8553, LP8555, LP8556 and
-	LP8557
-
-Author: Milo(Woogyom) Kim <milo.kim@ti.com>
-
-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.
-
-example 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,
-};
-
-example 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,
-};
diff --git a/MAINTAINERS b/MAINTAINERS
index 01c83e294f5f..37ba75bae7aa 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15964,7 +15964,7 @@ F:	sound/soc/codecs/isabelle*
 TI LP855x BACKLIGHT DRIVER
 M:	Milo Kim <milo.kim@ti.com>
 S:	Maintained
-F:	Documentation/backlight/lp855x-driver.txt
+F:	Documentation/backlight/lp855x-driver.rst
 F:	drivers/video/backlight/lp855x_bl.c
 F:	include/linux/platform_data/lp855x.h