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authorSteffen Trumtrar <s.trumtrar@pengutronix.de>2013-05-30 09:50:12 +0200
committerThierry Reding <thierry.reding@gmail.com>2013-06-12 13:13:18 +0200
commit88b613e6234def882b0b601bf831bf89af2e27f0 (patch)
treef864f8df0292c43ef902ac893fcb0fb66b7d8256 /Documentation/devicetree
parent8796f9c5656dedd186eda88c07db6a58d1985938 (diff)
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pwm: add pca9685 driver
Add pwm driver for the NXP pca9685 16 channel pwm-led controller. The driver is really barebones at this stage. E.g. the OE' pin and therefore the corresponding registers are not supported. The driver was tested on a HW where this pin is tied to GND. Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de> [thierry.reding@gmail.com: style and whitespace cleanups] Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'Documentation/devicetree')
-rw-r--r--Documentation/devicetree/bindings/pwm/nxp,pca9685-pwm.txt27
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diff --git a/Documentation/devicetree/bindings/pwm/nxp,pca9685-pwm.txt b/Documentation/devicetree/bindings/pwm/nxp,pca9685-pwm.txt
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+NXP PCA9685 16-channel 12-bit PWM LED controller
+================================================
+
+Required properties:
+ - compatible: "nxp,pca9685-pwm"
+ - #pwm-cells: should be 2. The first cell specifies the per-chip index
+ of the PWM to use and the second cell is the period in nanoseconds.
+ The index 16 is the ALLCALL channel, that sets all PWM channels at the same
+ time.
+
+Optional properties:
+ - invert (bool): boolean to enable inverted logic
+ - open-drain (bool): boolean to configure outputs with open-drain structure;
+ if omitted use totem-pole structure
+
+Example:
+
+For LEDs that are directly connected to the PCA, the following setting is
+applicable:
+
+pca: pca@41 {
+ compatible = "nxp,pca9685-pwm";
+ #pwm-cells = <2>;
+ reg = <0x41>;
+ invert;
+ open-drain;
+};