Re: [PATCH RFC] pwm: add sysfs interface

From: Greg KH
Date: Sun Feb 24 2013 - 22:57:30 EST

On Tue, Feb 19, 2013 at 03:27:41PM +0100, Lars Poeschel wrote:
> From: Lars Poeschel <poeschel@xxxxxxxxxxx>
> This adds a simple sysfs interface to the pwm subsystem. It is
> heavily inspired by the gpio sysfs interface.
> /sys/class/pwm
> /export ... asks the kernel to export a PWM to userspace
> /unexport ... to return a PWM to the kernel
> /pwmN ... for each exported PWM #N
> /duty_ns ... r/w, length of duty portion
> /period_ns ... r/w, length of the pwm period
> /polarity ... r/w, normal(0) or inverse(1) polarity
> only created if driver supports it
> /run ... r/w, write 1 to start and 0 to stop the pwm
> /pwmchipN ... for each pwmchip; #N is its first PWM
> /base ... (r/o) same as N
> /ngpio ... (r/o) number of PWM; numbered N .. MAX_PWMS

You have to document this all in the Documentation/ABI/ directory for
sysfs files. Please do that in your next version of this patch.


greg k-h
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