fbdev: LCD backlight driver using Atmel PWM driver

This patch adds a platform driver using the ATMEL PWM driver to control a
backlight which requires a PWM signal and optional GPIO signal for discrete
on/off signal.  It has been tested on Favr-32 board from EarthLCD.

The driver is configurable by supplying a struct with the platform data.  See
the include/linux/atmel-pwm-bl.h for details.

The board code for Favr-32 will be submitted to the AVR32 kernel list.

Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.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>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index b289e197e55..98d9faf4970 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -87,6 +87,18 @@ config BACKLIGHT_ATMEL_LCDC
           If in doubt, it's safe to enable this option; it doesn't kick
           in unless the board's description says it's wired that way.
 
+config BACKLIGHT_ATMEL_PWM
+        tristate "Atmel PWM backlight control"
+        depends on BACKLIGHT_CLASS_DEVICE && ATMEL_PWM
+        default n
+        help
+          Say Y here if you want to use the PWM peripheral in Atmel AT91 and
+          AVR32 devices. This driver will need additional platform data to know
+          which PWM instance to use and how to configure it.
+
+          To compile this driver as a module, choose M here: the module will be
+          called atmel-pwm-bl.
+
 config BACKLIGHT_CORGI
         tristate "Generic (aka Sharp Corgi) Backlight Driver"
         depends on BACKLIGHT_CLASS_DEVICE