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-rw-r--r--Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt12
-rw-r--r--Documentation/devicetree/bindings/pwm/mxs-pwm.txt17
-rw-r--r--Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt18
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm.txt57
4 files changed, 104 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt b/Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt
new file mode 100644
index 00000000000..cfe1db3bb6e
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/lpc32xx-pwm.txt
@@ -0,0 +1,12 @@
+LPC32XX PWM controller
+
+Required properties:
+- compatible: should be "nxp,lpc3220-pwm"
+- reg: physical base address and length of the controller's registers
+
+Examples:
+
+pwm@0x4005C000 {
+ compatible = "nxp,lpc3220-pwm";
+ reg = <0x4005C000 0x8>;
+};
diff --git a/Documentation/devicetree/bindings/pwm/mxs-pwm.txt b/Documentation/devicetree/bindings/pwm/mxs-pwm.txt
new file mode 100644
index 00000000000..b16f4a57d11
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/mxs-pwm.txt
@@ -0,0 +1,17 @@
+Freescale MXS PWM controller
+
+Required properties:
+- compatible: should be "fsl,imx23-pwm"
+- reg: physical base address and length of the controller's registers
+- #pwm-cells: should be 2. The first cell specifies the per-chip index
+ of the PWM to use and the second cell is the duty cycle in nanoseconds.
+- fsl,pwm-number: the number of PWM devices
+
+Example:
+
+pwm: pwm@80064000 {
+ compatible = "fsl,imx28-pwm", "fsl,imx23-pwm";
+ reg = <0x80064000 2000>;
+ #pwm-cells = <2>;
+ fsl,pwm-number = <8>;
+};
diff --git a/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt b/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt
new file mode 100644
index 00000000000..bbbeedb4ec0
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt
@@ -0,0 +1,18 @@
+Tegra SoC PWFM controller
+
+Required properties:
+- compatible: should be one of:
+ - "nvidia,tegra20-pwm"
+ - "nvidia,tegra30-pwm"
+- reg: physical base address and length of the controller's registers
+- #pwm-cells: On Tegra the number of cells used to specify a PWM is 2. The
+ first cell specifies the per-chip index of the PWM to use and the second
+ cell is the duty cycle in nanoseconds.
+
+Example:
+
+ pwm: pwm@7000a000 {
+ compatible = "nvidia,tegra20-pwm";
+ reg = <0x7000a000 0x100>;
+ #pwm-cells = <2>;
+ };
diff --git a/Documentation/devicetree/bindings/pwm/pwm.txt b/Documentation/devicetree/bindings/pwm/pwm.txt
new file mode 100644
index 00000000000..73ec962bfe8
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+++ b/Documentation/devicetree/bindings/pwm/pwm.txt
@@ -0,0 +1,57 @@
+Specifying PWM information for devices
+======================================
+
+1) PWM user nodes
+-----------------
+
+PWM users should specify a list of PWM devices that they want to use
+with a property containing a 'pwm-list':
+
+ pwm-list ::= <single-pwm> [pwm-list]
+ single-pwm ::= <pwm-phandle> <pwm-specifier>
+ pwm-phandle : phandle to PWM controller node
+ pwm-specifier : array of #pwm-cells specifying the given PWM
+ (controller specific)
+
+PWM properties should be named "pwms". The exact meaning of each pwms
+property must be documented in the device tree binding for each device.
+An optional property "pwm-names" may contain a list of strings to label
+each of the PWM devices listed in the "pwms" property. If no "pwm-names"
+property is given, the name of the user node will be used as fallback.
+
+Drivers for devices that use more than a single PWM device can use the
+"pwm-names" property to map the name of the PWM device requested by the
+pwm_get() call to an index into the list given by the "pwms" property.
+
+The following example could be used to describe a PWM-based backlight
+device:
+
+ pwm: pwm {
+ #pwm-cells = <2>;
+ };
+
+ [...]
+
+ bl: backlight {
+ pwms = <&pwm 0 5000000>;
+ pwm-names = "backlight";
+ };
+
+pwm-specifier typically encodes the chip-relative PWM number and the PWM
+period in nanoseconds. Note that in the example above, specifying the
+"pwm-names" is redundant because the name "backlight" would be used as
+fallback anyway.
+
+2) PWM controller nodes
+-----------------------
+
+PWM controller nodes must specify the number of cells used for the
+specifier using the '#pwm-cells' property.
+
+An example PWM controller might look like this:
+
+ pwm: pwm@7000a000 {
+ compatible = "nvidia,tegra20-pwm";
+ reg = <0x7000a000 0x100>;
+ #pwm-cells = <2>;
+ };