leds: Add LED Flash class extension to the LED subsystem
Some LED devices support two operation modes - torch and flash.
This patch provides support for flash LED devices in the LED subsystem
by introducing new sysfs attributes and kernel internal interface.
The attributes being introduced are: flash_brightness, flash_strobe,
flash_timeout, max_flash_timeout, max_flash_brightness, flash_fault,
flash_sync_strobe and available_sync_leds. All the flash related
features are placed in a separate module.
The modifications aim to be compatible with V4L2 framework requirements
related to the flash devices management. The design assumes that V4L2
sub-device can take of the LED class device control and communicate
with it through the kernel internal interface. When V4L2 Flash sub-device
file is opened, the LED class device sysfs interface is made
unavailable.
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index a6c3d2f..25b320d 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -22,6 +22,16 @@
This option enables the led sysfs class in /sys/class/leds. You'll
need this to do anything useful with LEDs. If unsure, say N.
+config LEDS_CLASS_FLASH
+ tristate "LED Flash Class Support"
+ depends on LEDS_CLASS
+ help
+ This option enables the flash led sysfs class in /sys/class/leds.
+ It wrapps LED Class and adds flash LEDs specific sysfs attributes
+ and kernel internal API to it. You'll need this to provide support
+ for the flash related features of a LED device. It can be built
+ as a module.
+
comment "LED drivers"
config LEDS_88PM860X