leds: is31fl319x: 1/3/6/9-channel light effect led driver

This is a driver for the Integrated Silicon Solution Inc. LED driver
chips series IS31FL319x. They can drive 1, 3, 6  or up to 9
LEDs.

Each LED is individually controllable in brightness (through pwm)
in 256 steps so that RGB LEDs can show any of ca. 16 Mio colors.

The maximum current of the LEDs can be programmed and limited to
5 .. 40mA through a device tree property.

The chip is connected through I2C and can have one of 4 addresses
in the range 0x64 .. 0x67 depending on how the AD pin is connected. The
address is defined by the reg property as usual.

The chip also has a shutdown input which could be connected to a GPIO,
but this driver uses software shutdown if all LEDs are inactivated.

The chip also has breathing and audio features which are not fully
supported by this driver.

Tested-on: OMAP5 based Pyra handheld prototype.
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Andrey Utkin <andrey_utkin@fastmail.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>

drivers/leds/Kconfig

@@ -584,6 +584,18 @@ config LEDS_SEAD3
 	  This driver can also be built as a module. If so the module
 	  will be called leds-sead3.
 
+config LEDS_IS31FL319X
+	tristate "LED Support for ISSI IS31FL319x I2C LED controller family"
+	depends on LEDS_CLASS && I2C && OF
+	select REGMAP_I2C
+	help
+	  This option enables support for LEDs connected to ISSI IS31FL319x
+	  fancy LED driver chips accessed via the I2C bus.
+	  Driver supports individual PWM brightness control for each channel.
+
+	  This driver can also be built as a module. If so the module will be
+	  called leds-is31fl319x.
+
 config LEDS_IS31FL32XX
 	tristate "LED support for ISSI IS31FL32XX I2C LED controller family"
 	depends on LEDS_CLASS && I2C && OF

drivers/leds/Makefile

@@ -67,6 +67,7 @@ obj-$(CONFIG_LEDS_MENF21BMC)		+= leds-menf21bmc.o
 obj-$(CONFIG_LEDS_KTD2692)		+= leds-ktd2692.o
 obj-$(CONFIG_LEDS_POWERNV)		+= leds-powernv.o
 obj-$(CONFIG_LEDS_SEAD3)		+= leds-sead3.o
+obj-$(CONFIG_LEDS_IS31FL319X)		+= leds-is31fl319x.o
 obj-$(CONFIG_LEDS_IS31FL32XX)		+= leds-is31fl32xx.o
 
 # LED SPI Drivers