backlight: add support for Pandora backlight

Add support for pandora (openpandora.org) backlight.

It might look like all this could be done using pwm_bl.c instead, but
there is a need of special programming sequence when turning on the LED
driver chip or else it will misbehave.  Doing this using pwm_bl.c would
require to use some register programming and pwm functions from platform
code, and ARM maintainers are allergic to driver-like code in /arch/arm
nowadays.  The PMIC PWM driver is currently missing too, so pwm_bl.c
can't be used anyway.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.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>
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 248d6c0..ed68fde5 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -348,6 +348,13 @@
 	  To compile this driver as a module, choose M here: the module will be
 	  called ot200_bl.
 
+config BACKLIGHT_PANDORA
+	tristate "Backlight driver for Pandora console"
+	depends on TWL4030_CORE
+	help
+	  If you have a Pandora console, say Y to enable the
+	  backlight driver.
+
 endif # BACKLIGHT_CLASS_DEVICE
 
 endif # BACKLIGHT_LCD_SUPPORT