blob: a17f817a93095b22f12b9aff657c0dd50c845fc7 [file] [log] [blame]
Richard Cochrand94ba802011-04-22 12:03:08 +02001What: /sys/class/ptp/
2Date: September 2010
3Contact: Richard Cochran <richardcochran@gmail.com>
4Description:
5 This directory contains files and directories
6 providing a standardized interface to the ancillary
7 features of PTP hardware clocks.
8
9What: /sys/class/ptp/ptpN/
10Date: September 2010
11Contact: Richard Cochran <richardcochran@gmail.com>
12Description:
13 This directory contains the attributes of the Nth PTP
14 hardware clock registered into the PTP class driver
15 subsystem.
16
17What: /sys/class/ptp/ptpN/clock_name
18Date: September 2010
19Contact: Richard Cochran <richardcochran@gmail.com>
20Description:
21 This file contains the name of the PTP hardware clock
Richard Cochrande465842012-09-22 07:02:04 +000022 as a human readable string. The purpose of this
23 attribute is to provide the user with a "friendly
24 name" and to help distinguish PHY based devices from
25 MAC based ones. The string does not necessarily have
26 to be any kind of unique id.
Richard Cochrand94ba802011-04-22 12:03:08 +020027
28What: /sys/class/ptp/ptpN/max_adjustment
29Date: September 2010
30Contact: Richard Cochran <richardcochran@gmail.com>
31Description:
32 This file contains the PTP hardware clock's maximum
33 frequency adjustment value (a positive integer) in
34 parts per billion.
35
36What: /sys/class/ptp/ptpN/n_alarms
37Date: September 2010
38Contact: Richard Cochran <richardcochran@gmail.com>
39Description:
40 This file contains the number of periodic or one shot
41 alarms offer by the PTP hardware clock.
42
43What: /sys/class/ptp/ptpN/n_external_timestamps
44Date: September 2010
45Contact: Richard Cochran <richardcochran@gmail.com>
46Description:
47 This file contains the number of external timestamp
48 channels offered by the PTP hardware clock.
49
50What: /sys/class/ptp/ptpN/n_periodic_outputs
51Date: September 2010
52Contact: Richard Cochran <richardcochran@gmail.com>
53Description:
54 This file contains the number of programmable periodic
55 output channels offered by the PTP hardware clock.
56
Richard Cochran653104d2014-03-20 22:21:54 +010057What: /sys/class/ptp/ptpN/n_pins
58Date: March 2014
59Contact: Richard Cochran <richardcochran@gmail.com>
60Description:
61 This file contains the number of programmable pins
62 offered by the PTP hardware clock.
63
64What: /sys/class/ptp/ptpN/pins
65Date: March 2014
66Contact: Richard Cochran <richardcochran@gmail.com>
67Description:
68 This directory contains one file for each programmable
69 pin offered by the PTP hardware clock. The file name
70 is the hardware dependent pin name. Reading from this
71 file produces two numbers, the assigned function (see
72 the PTP_PF_ enumeration values in linux/ptp_clock.h)
73 and the channel number. The function and channel
74 assignment may be changed by two writing numbers into
75 the file.
76
Chris Dunlopd83e2a42015-09-18 16:10:55 +100077What: /sys/class/ptp/ptpN/pps_available
Richard Cochrand94ba802011-04-22 12:03:08 +020078Date: September 2010
79Contact: Richard Cochran <richardcochran@gmail.com>
80Description:
81 This file indicates whether the PTP hardware clock
82 supports a Pulse Per Second to the host CPU. Reading
83 "1" means that the PPS is supported, while "0" means
84 not supported.
85
86What: /sys/class/ptp/ptpN/extts_enable
87Date: September 2010
88Contact: Richard Cochran <richardcochran@gmail.com>
89Description:
90 This write-only file enables or disables external
91 timestamps. To enable external timestamps, write the
92 channel index followed by a "1" into the file.
93 To disable external timestamps, write the channel
94 index followed by a "0" into the file.
95
96What: /sys/class/ptp/ptpN/fifo
97Date: September 2010
98Contact: Richard Cochran <richardcochran@gmail.com>
99Description:
100 This file provides timestamps on external events, in
101 the form of three integers: channel index, seconds,
102 and nanoseconds.
103
104What: /sys/class/ptp/ptpN/period
105Date: September 2010
106Contact: Richard Cochran <richardcochran@gmail.com>
107Description:
108 This write-only file enables or disables periodic
109 outputs. To enable a periodic output, write five
110 integers into the file: channel index, start time
111 seconds, start time nanoseconds, period seconds, and
112 period nanoseconds. To disable a periodic output, set
113 all the seconds and nanoseconds values to zero.
114
115What: /sys/class/ptp/ptpN/pps_enable
116Date: September 2010
117Contact: Richard Cochran <richardcochran@gmail.com>
118Description:
119 This write-only file enables or disables delivery of
120 PPS events to the Linux PPS subsystem. To enable PPS
121 events, write a "1" into the file. To disable events,
122 write a "0" into the file.