pwm: Improve Kconfig help text

The Kconfig help text should help the user understand what functionality
is provided by an option. This is especially true for new subsystems. An
improved help text is provided by this commit in the hopes of clarifying
the usefulness of the PWM framework.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Acked-by: Borislav Petkov <bp@alien8.de>
This commit is contained in:
Thierry Reding 2012-08-16 08:01:21 +02:00
parent e50d3523ff
commit b817bf5c72

View file

@ -1,12 +1,31 @@
menuconfig PWM
bool "PWM Support"
bool "Pulse-Width Modulation (PWM) Support"
depends on !MACH_JZ4740 && !PUV3_PWM
help
This enables PWM support through the generic PWM framework.
You only need to enable this, if you also want to enable
one or more of the PWM drivers below.
Generic Pulse-Width Modulation (PWM) support.
If unsure, say N.
In Pulse-Width Modulation, a variation of the width of pulses
in a rectangular pulse signal is used as a means to alter the
average power of the signal. Applications include efficient
power delivery and voltage regulation. In computer systems,
PWMs are commonly used to control fans or the brightness of
display backlights.
This framework provides a generic interface to PWM devices
within the Linux kernel. On the driver side it provides an API
to register and unregister a PWM chip, an abstraction of a PWM
controller, that supports one or more PWM devices. Client
drivers can request PWM devices and use the generic framework
to configure as well as enable and disable them.
This generic framework replaces the legacy PWM framework which
allows only a single driver implementing the required API. Not
all legacy implementations have been ported to the framework
yet. The framework provides an API that is backward compatible
with the legacy framework so that existing client drivers
continue to work as expected.
If unsure, say no.
if PWM