[PATCH 2/3] dt-bindings: leds: Add binding for sgm3140

[Luca Weiss <luca@z3ntu.xyz>]

Add YAML devicetree binding for SGMICRO SGM3140 charge pump used for
camera flash LEDs.

Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
---
Changes since RFC:
- new patch

I'm not sure about the completeness of this binding as it doesn't
mention the led subnode at all.
The only existing led yaml binding is leds/leds-max77650.yaml which
mentions the subnode but duplicates properties from documented in 
leds/common.txt.

 .../bindings/leds/leds-sgm3140.yaml           | 53 +++++++++++++++++++
 1 file changed, 53 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/leds-sgm3140.yaml

diff --git a/Documentation/devicetree/bindings/leds/leds-sgm3140.yaml b/Documentation/devicetree/bindings/leds/leds-sgm3140.yaml
new file mode 100644
index 000000000000..be9384573d02
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-sgm3140.yaml
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/leds-sgm3140.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SGMICRO SGM3140 500mA Buck/Boost Charge Pump LED Driver
+
+maintainers:
+  - Luca Weiss <luca@z3ntu.xyz>
+
+description: |
+  The SGM3140 is a current-regulated charge pump which can regulate two current
+  levels for Flash and Torch modes.
+
+  It is controlled with two GPIO pins.
+
+  The data sheet can be found at:
+    http://www.sg-micro.com/uploads/soft/20190626/1561535688.pdf
+
+properties:
+  compatible:
+    const: sgmicro,sgm3140
+
+  enable-gpios:
+    maxItems: 1
+    description: A connection to the 'EN' pin.
+
+  flash-gpios:
+    maxItems: 1
+    description: A connection to the 'FLASH' pin.
+
+required:
+  - compatible
+  - flash-gpios
+  - enable-gpios
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/leds/common.h>
+
+    sgm3140 {
+        compatible = "sgmicro,sgm3140";
+        flash-gpios = <&pio 3 24 GPIO_ACTIVE_HIGH>; /* PD24 */
+        enable-gpios = <&pio 2 3 GPIO_ACTIVE_HIGH>; /* PC3 */
+
+        sgm3140_flash: led {
+            function = LED_FUNCTION_FLASH;
+            color = <LED_COLOR_ID_WHITE>;
+            flash-max-timeout-us = <250000>;
+        };
+    };
-- 
2.25.1