pwm: New driver to support PWM driven LEDs on TWL4030/6030 series of PMICs

The driver supports the following LED outputs as generic PWM driver:
TWL4030 LEDA and LEDB (PWMA and PWMB)
TWL6030 Charging indicator LED (PWM LED)

On TWL6030 when the PWM requested LED is configured to be controlled by SW.
In this case the user can enable/disable and set the duty period freely.
When the PWM has been freed, the LED driver is put back to HW control.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

1 files changed, 17 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/pwm/ti,twl-pwmled.txt b/Documentation/devicetree/bindings/pwm/ti,twl-pwmled.txt
new file mode 100644
index 000000000000..cb64f3acc10f
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/ti,twl-pwmled.txt
@@ -0,0 +1,17 @@
+Texas Instruments TWL series PWM drivers connected to LED terminals
+
+Supported PWMs:
+On TWL4030 series: PWMA and PWMB (connected to LEDA and LEDB terminals)
+On TWL6030 series: LED PWM (mainly used as charging indicator LED)
+
+Required properties:
+- compatible: "ti,twl4030-pwmled" or "ti,twl6030-pwmled"
+- #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.
+
+Example:
+
+twl_pwmled: pwmled {
+        compatible = "ti,twl6030-pwmled";
+        #pwm-cells = <2>;
+};