pwm: Standardize document format
Each text file under Documentation follows a different format. Some
don't even have titles!
Change its representation to follow the adopted standard, using ReST
markup for it to be parseable by Sphinx:
- mark document title;
- mark literal blocks;
- better format the parameters.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
diff --git a/Documentation/pwm.txt b/Documentation/pwm.txt
index 789b27c..8fbf0aa 100644
--- a/Documentation/pwm.txt
+++ b/Documentation/pwm.txt
@@ -1,4 +1,6 @@
+======================================
Pulse Width Modulation (PWM) interface
+======================================
This provides an overview about the Linux PWM interface
@@ -16,7 +18,7 @@
Instead of referring to a PWM device via its unique ID, board setup code
should instead register a static mapping that can be used to match PWM
-consumers to providers, as given in the following example:
+consumers to providers, as given in the following example::
static struct pwm_lookup board_pwm_lookup[] = {
PWM_LOOKUP("tegra-pwm", 0, "pwm-backlight", NULL,
@@ -40,9 +42,9 @@
device or a consumer name. pwm_put() is used to free the PWM device. Managed
variants of these functions, devm_pwm_get() and devm_pwm_put(), also exist.
-After being requested, a PWM has to be configured using:
+After being requested, a PWM has to be configured using::
-int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state);
+ int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state);
This API controls both the PWM period/duty_cycle config and the
enable/disable state.
@@ -72,11 +74,14 @@
pwmchipN, where N is the base of the PWM chip. Inside the directory you
will find:
-npwm - The number of PWM channels this chip supports (read-only).
+ npwm
+ The number of PWM channels this chip supports (read-only).
-export - Exports a PWM channel for use with sysfs (write-only).
+ export
+ Exports a PWM channel for use with sysfs (write-only).
-unexport - Unexports a PWM channel from sysfs (write-only).
+ unexport
+ Unexports a PWM channel from sysfs (write-only).
The PWM channels are numbered using a per-chip index from 0 to npwm-1.
@@ -84,21 +89,26 @@
pwmchipN directory it is associated with, where X is the number of the
channel that was exported. The following properties will then be available:
-period - The total period of the PWM signal (read/write).
- Value is in nanoseconds and is the sum of the active and inactive
- time of the PWM.
+ period
+ The total period of the PWM signal (read/write).
+ Value is in nanoseconds and is the sum of the active and inactive
+ time of the PWM.
-duty_cycle - The active time of the PWM signal (read/write).
- Value is in nanoseconds and must be less than the period.
+ duty_cycle
+ The active time of the PWM signal (read/write).
+ Value is in nanoseconds and must be less than the period.
-polarity - Changes the polarity of the PWM signal (read/write).
- Writes to this property only work if the PWM chip supports changing
- the polarity. The polarity can only be changed if the PWM is not
- enabled. Value is the string "normal" or "inversed".
+ polarity
+ Changes the polarity of the PWM signal (read/write).
+ Writes to this property only work if the PWM chip supports changing
+ the polarity. The polarity can only be changed if the PWM is not
+ enabled. Value is the string "normal" or "inversed".
-enable - Enable/disable the PWM signal (read/write).
- 0 - disabled
- 1 - enabled
+ enable
+ Enable/disable the PWM signal (read/write).
+
+ - 0 - disabled
+ - 1 - enabled
Implementing a PWM driver
-------------------------
