GNU Linux-libre 4.4.294-gnu1
[releases.git] / Documentation / ABI / testing / sysfs-class-pwm
1 What:           /sys/class/pwm/
2 Date:           May 2013
3 KernelVersion:  3.11
4 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
5 Description:
6                 The pwm/ class sub-directory belongs to the Generic PWM
7                 Framework and provides a sysfs interface for using PWM
8                 channels.
9
10 What:           /sys/class/pwm/pwmchipN/
11 Date:           May 2013
12 KernelVersion:  3.11
13 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
14 Description:
15                 A /sys/class/pwm/pwmchipN directory is created for each
16                 probed PWM controller/chip where N is the base of the
17                 PWM chip.
18
19 What:           /sys/class/pwm/pwmchipN/npwm
20 Date:           May 2013
21 KernelVersion:  3.11
22 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
23 Description:
24                 The number of PWM channels supported by the PWM chip.
25
26 What:           /sys/class/pwm/pwmchipN/export
27 Date:           May 2013
28 KernelVersion:  3.11
29 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
30 Description:
31                 Exports a PWM channel from the PWM chip for sysfs control.
32                 Value is between 0 and /sys/class/pwm/pwmchipN/npwm - 1.
33
34 What:           /sys/class/pwm/pwmchipN/unexport
35 Date:           May 2013
36 KernelVersion:  3.11
37 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
38 Description:
39                 Unexports a PWM channel.
40
41 What:           /sys/class/pwm/pwmchipN/pwmX
42 Date:           May 2013
43 KernelVersion:  3.11
44 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
45 Description:
46                 A /sys/class/pwm/pwmchipN/pwmX directory is created for
47                 each exported PWM channel where X is the exported PWM
48                 channel number.
49
50 What:           /sys/class/pwm/pwmchipN/pwmX/period
51 Date:           May 2013
52 KernelVersion:  3.11
53 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
54 Description:
55                 Sets the PWM signal period in nanoseconds.
56
57 What:           /sys/class/pwm/pwmchipN/pwmX/duty_cycle
58 Date:           May 2013
59 KernelVersion:  3.11
60 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
61 Description:
62                 Sets the PWM signal duty cycle in nanoseconds.
63
64 What:           /sys/class/pwm/pwmchipN/pwmX/polarity
65 Date:           May 2013
66 KernelVersion:  3.11
67 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
68 Description:
69                 Sets the output polarity of the PWM signal to "normal" or
70                 "inversed".
71
72 What:           /sys/class/pwm/pwmchipN/pwmX/enable
73 Date:           May 2013
74 KernelVersion:  3.11
75 Contact:        H Hartley Sweeten <hsweeten@visionengravers.com>
76 Description:
77                 Enable/disable the PWM signal.
78                 0 is disabled
79                 1 is enabled