Add documentation for PWM push-pull mode.
Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
---
Documentation/devicetree/bindings/pwm/pwm.txt | 2 ++
Documentation/pwm.txt | 16 ++++++++++++++++
include/dt-bindings/pwm/pwm.h | 1 +
3 files changed, 19 insertions(+)
diff --git a/Documentation/devicetree/bindings/pwm/pwm.txt b/Documentation/devicetree/bindings/pwm/pwm.txt
index 7c8aaac43f92..6a60c0fca112 100644
--- a/Documentation/devicetree/bindings/pwm/pwm.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm.txt
@@ -49,6 +49,8 @@ Optionally, the pwm-specifier can encode a number of flags (defined in
- PWM_MODE_COMPLEMENTARY: PWM complementary working mode (for PWM channels
with two outputs); if not specified, the default for PWM channel will be
used
+- PWM_MODE_PUSH_PULL: PWM push-pull working modes (for PWM channels with
+two outputs); if not specified the default for PWM channel will be used
Example with optional PWM specifier for inverse polarity and complementary
mode:
diff --git a/Documentation/pwm.txt b/Documentation/pwm.txt
index 912c43da8b48..675f9351fed1 100644
--- a/Documentation/pwm.txt
+++ b/Documentation/pwm.txt
@@ -128,6 +128,22 @@ channel that was exported. The following properties will then be available:
PWML1 |__| |__| |__| |__|
<--T-->
+ Push-pull mode - for PWM channels with two outputs; output waveforms
+ for a PWM channel in push-pull mode, with normal polarity looks like
+ this:
+ __ __
+ PWMH __| |________| |________
+ __ __
+ PWML ________| |________| |__
+ <--T-->
+
+ If polarity is inversed:
+ __ ________ ________
+ PWMH |__| |__|
+ ________ ________ __
+ PWML |__| |__|
+ <--T-->
+
Where T is the signal period.
Implementing a PWM driver
diff --git a/include/dt-bindings/pwm/pwm.h b/include/dt-bindings/pwm/pwm.h
index b82279cc1787..cd4265bce968 100644
--- a/include/dt-bindings/pwm/pwm.h
+++ b/include/dt-bindings/pwm/pwm.h
@@ -12,5 +12,6 @@
#define PWM_POLARITY_INVERTED (1 << 0)
#define PWM_MODE_COMPLEMENTARY (1 << 1)
+#define PWM_MODE_PUSH_PULL (1 << 2)
#endif
--
2.7.4
