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+* Skyworks Solutions, Inc. AAT1290 Current Regulator for Flash LEDs
+
+The device is controlled through two pins: FL_EN and EN_SET. The pins when,
+asserted high, enable flash strobe and movie mode (max 1/2 of flash current)
+respectively. In order to add a capability of selecting the strobe signal source
+(e.g. CPU or camera sensor) there is an additional switch required, independent
+of the flash chip. The switch is controlled with pin control.
+
+Required properties:
+
+- compatible : Must be "skyworks,aat1290".
+- flen-gpios : Must be device tree identifier of the flash device FL_EN pin.
+- enset-gpios : Must be device tree identifier of the flash device EN_SET pin.
+
+Optional properties:
+- pinctrl-names : Must contain entries: "default", "host", "isp". Entries
+ "default" and "host" must refer to the same pin configuration
+ node, which sets the host as a strobe signal provider. Entry
+ "isp" must refer to the pin configuration node, which sets the
+ ISP as a strobe signal provider.
+
+A discrete LED element connected to the device must be represented by a child
+node - see Documentation/devicetree/bindings/leds/common.txt.
+
+Required properties of the LED child node:
+- led-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+ Maximum flash LED supply current can be calculated using
+ following formula: I = 1A * 162kohm / Rset.
+- flash-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
+ Maximum flash timeout can be calculated using following
+ formula: T = 8.82 * 10^9 * Ct.
+
+Optional properties of the LED child node:
+- label : see Documentation/devicetree/bindings/leds/common.txt
+
+Example (by Ct = 220nF, Rset = 160kohm and exynos4412-trats2 board with
+a switch that allows for routing strobe signal either from the host or from
+the camera sensor):
+
+#include "exynos4412.dtsi"
+
+aat1290 {
+ compatible = "skyworks,aat1290";
+ flen-gpios = <&gpj1 1 GPIO_ACTIVE_HIGH>;
+ enset-gpios = <&gpj1 2 GPIO_ACTIVE_HIGH>;
+
+ pinctrl-names = "default", "host", "isp";
+ pinctrl-0 = <&camera_flash_host>;
+ pinctrl-1 = <&camera_flash_host>;
+ pinctrl-2 = <&camera_flash_isp>;
+
+ camera_flash: flash-led {
+ label = "aat1290-flash";
+ led-max-microamp = <520833>;
+ flash-max-microamp = <1012500>;
+ flash-timeout-us = <1940000>;
+ };
+};
+
+&pinctrl_0 {
+ camera_flash_host: camera-flash-host {
+ samsung,pins = "gpj1-0";
+ samsung,pin-function = <1>;
+ samsung,pin-val = <0>;
+ };
+
+ camera_flash_isp: camera-flash-isp {
+ samsung,pins = "gpj1-0";
+ samsung,pin-function = <1>;
+ samsung,pin-val = <1>;
+ };
+};