linux/linux-5.18.11/Documentation/ABI/testing/sysfs-class-pwm

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2024-03-22 18:12:32 +00:00
What: /sys/class/pwm/
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
The pwm/ class sub-directory belongs to the Generic PWM
Framework and provides a sysfs interface for using PWM
channels.
What: /sys/class/pwm/pwmchip<N>/
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
A /sys/class/pwm/pwmchipN directory is created for each
probed PWM controller/chip where N is the base of the
PWM chip.
What: /sys/class/pwm/pwmchip<N>/npwm
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
The number of PWM channels supported by the PWM chip.
What: /sys/class/pwm/pwmchip<N>/export
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
Exports a PWM channel from the PWM chip for sysfs control.
Value is between 0 and /sys/class/pwm/pwmchipN/npwm - 1.
What: /sys/class/pwm/pwmchip<N>/unexport
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
Unexports a PWM channel.
What: /sys/class/pwm/pwmchip<N>/pwmX
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
A /sys/class/pwm/pwmchipN/pwmX directory is created for
each exported PWM channel where X is the exported PWM
channel number.
What: /sys/class/pwm/pwmchip<N>/pwmX/period
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
Sets the PWM signal period in nanoseconds.
What: /sys/class/pwm/pwmchip<N>/pwmX/duty_cycle
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
Sets the PWM signal duty cycle in nanoseconds.
What: /sys/class/pwm/pwmchip<N>/pwmX/polarity
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
Sets the output polarity of the PWM signal to "normal" or
"inversed".
What: /sys/class/pwm/pwmchip<N>/pwmX/enable
Date: May 2013
KernelVersion: 3.11
Contact: H Hartley Sweeten <hsweeten@visionengravers.com>
Description:
Enable/disable the PWM signal.
0 is disabled
1 is enabled
What: /sys/class/pwm/pwmchip<N>/pwmX/capture
Date: June 2016
KernelVersion: 4.8
Contact: Lee Jones <lee.jones@linaro.org>
Description:
Capture information about a PWM signal. The output format is a
pair unsigned integers (period and duty cycle), separated by a
single space.