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path: root/drivers/pwm
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-rw-r--r--drivers/pwm/Kconfig31
1 files changed, 25 insertions, 6 deletions
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 8fc3808d7a3e..90c5c7357a50 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -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.
-
- If unsure, say N.
+ Generic Pulse-Width Modulation (PWM) support.
+
+ 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