[PATCH v7 5/6] pwm: add documentation for pwm push-pull mode

From: Claudiu.Beznea
Date: Mon Dec 17 2018 - 09:14:39 EST


From: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>

Add documentation for PWM push-pull mode.

Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
---

Hi Rob,

In prevous version I had your Reviewed-by tag on this patch but I removed it
in this version since there are some changes b/w the previous one and this
one. Please see bellow and let me know if you are ok with this.

Thank you,
Claudiu Beznea

Changes in v6:
- remove bindings part
- use 1/3 duty factor ratio
- use '^' symbols to emphasize the beginning of a new period
- use PWMx_y to refrer to output y of PWM x

Documentation/pwm.txt | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/Documentation/pwm.txt b/Documentation/pwm.txt
index 669fd4c9cc8e..80552627627d 100644
--- a/Documentation/pwm.txt
+++ b/Documentation/pwm.txt
@@ -130,6 +130,22 @@ channel that was exported. The following properties will then be available:
PWMx_1 |__| |__| |__| |__|
^ ^ ^ ^

+ 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:
+ __ __
+ PWMx_0 __| |____________| |__________
+ __ __
+ PWMx_1 __________| |____________| |__
+ ^ ^ ^ ^
+
+ If polarity is inversed:
+ __ ____________ __________
+ PWMx_0 |__| |__|
+ __________ ____________ __
+ PWMx_1 |__| |__|
+ ^ ^ ^ ^
+
Where '^' specifies the beginning of a period.

Implementing a PWM driver
--
2.7.4