| Richard Cochran | d94ba80 | 2011-04-22 12:03:08 +0200 | [diff] [blame] | 1 | What: /sys/class/ptp/ |
| 2 | Date: September 2010 |
| 3 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 4 | Description: |
| 5 | This directory contains files and directories |
| 6 | providing a standardized interface to the ancillary |
| 7 | features of PTP hardware clocks. |
| 8 | |
| 9 | What: /sys/class/ptp/ptpN/ |
| 10 | Date: September 2010 |
| 11 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 12 | Description: |
| 13 | This directory contains the attributes of the Nth PTP |
| 14 | hardware clock registered into the PTP class driver |
| 15 | subsystem. |
| 16 | |
| 17 | What: /sys/class/ptp/ptpN/clock_name |
| 18 | Date: September 2010 |
| 19 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 20 | Description: |
| 21 | This file contains the name of the PTP hardware clock |
| 22 | as a human readable string. |
| 23 | |
| 24 | What: /sys/class/ptp/ptpN/max_adjustment |
| 25 | Date: September 2010 |
| 26 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 27 | Description: |
| 28 | This file contains the PTP hardware clock's maximum |
| 29 | frequency adjustment value (a positive integer) in |
| 30 | parts per billion. |
| 31 | |
| 32 | What: /sys/class/ptp/ptpN/n_alarms |
| 33 | Date: September 2010 |
| 34 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 35 | Description: |
| 36 | This file contains the number of periodic or one shot |
| 37 | alarms offer by the PTP hardware clock. |
| 38 | |
| 39 | What: /sys/class/ptp/ptpN/n_external_timestamps |
| 40 | Date: September 2010 |
| 41 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 42 | Description: |
| 43 | This file contains the number of external timestamp |
| 44 | channels offered by the PTP hardware clock. |
| 45 | |
| 46 | What: /sys/class/ptp/ptpN/n_periodic_outputs |
| 47 | Date: September 2010 |
| 48 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 49 | Description: |
| 50 | This file contains the number of programmable periodic |
| 51 | output channels offered by the PTP hardware clock. |
| 52 | |
| 53 | What: /sys/class/ptp/ptpN/pps_avaiable |
| 54 | Date: September 2010 |
| 55 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 56 | Description: |
| 57 | This file indicates whether the PTP hardware clock |
| 58 | supports a Pulse Per Second to the host CPU. Reading |
| 59 | "1" means that the PPS is supported, while "0" means |
| 60 | not supported. |
| 61 | |
| 62 | What: /sys/class/ptp/ptpN/extts_enable |
| 63 | Date: September 2010 |
| 64 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 65 | Description: |
| 66 | This write-only file enables or disables external |
| 67 | timestamps. To enable external timestamps, write the |
| 68 | channel index followed by a "1" into the file. |
| 69 | To disable external timestamps, write the channel |
| 70 | index followed by a "0" into the file. |
| 71 | |
| 72 | What: /sys/class/ptp/ptpN/fifo |
| 73 | Date: September 2010 |
| 74 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 75 | Description: |
| 76 | This file provides timestamps on external events, in |
| 77 | the form of three integers: channel index, seconds, |
| 78 | and nanoseconds. |
| 79 | |
| 80 | What: /sys/class/ptp/ptpN/period |
| 81 | Date: September 2010 |
| 82 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 83 | Description: |
| 84 | This write-only file enables or disables periodic |
| 85 | outputs. To enable a periodic output, write five |
| 86 | integers into the file: channel index, start time |
| 87 | seconds, start time nanoseconds, period seconds, and |
| 88 | period nanoseconds. To disable a periodic output, set |
| 89 | all the seconds and nanoseconds values to zero. |
| 90 | |
| 91 | What: /sys/class/ptp/ptpN/pps_enable |
| 92 | Date: September 2010 |
| 93 | Contact: Richard Cochran <richardcochran@gmail.com> |
| 94 | Description: |
| 95 | This write-only file enables or disables delivery of |
| 96 | PPS events to the Linux PPS subsystem. To enable PPS |
| 97 | events, write a "1" into the file. To disable events, |
| 98 | write a "0" into the file. |