sysfs-ptp 4.2 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122
  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. What: /sys/class/ptp/ptpN/
  9. Date: September 2010
  10. Contact: Richard Cochran <richardcochran@gmail.com>
  11. Description:
  12. This directory contains the attributes of the Nth PTP
  13. hardware clock registered into the PTP class driver
  14. subsystem.
  15. What: /sys/class/ptp/ptpN/clock_name
  16. Date: September 2010
  17. Contact: Richard Cochran <richardcochran@gmail.com>
  18. Description:
  19. This file contains the name of the PTP hardware clock
  20. as a human readable string. The purpose of this
  21. attribute is to provide the user with a "friendly
  22. name" and to help distinguish PHY based devices from
  23. MAC based ones. The string does not necessarily have
  24. to be any kind of unique id.
  25. What: /sys/class/ptp/ptpN/max_adjustment
  26. Date: September 2010
  27. Contact: Richard Cochran <richardcochran@gmail.com>
  28. Description:
  29. This file contains the PTP hardware clock's maximum
  30. frequency adjustment value (a positive integer) in
  31. parts per billion.
  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. What: /sys/class/ptp/ptpN/n_external_timestamps
  39. Date: September 2010
  40. Contact: Richard Cochran <richardcochran@gmail.com>
  41. Description:
  42. This file contains the number of external timestamp
  43. channels offered by the PTP hardware clock.
  44. What: /sys/class/ptp/ptpN/n_periodic_outputs
  45. Date: September 2010
  46. Contact: Richard Cochran <richardcochran@gmail.com>
  47. Description:
  48. This file contains the number of programmable periodic
  49. output channels offered by the PTP hardware clock.
  50. What: /sys/class/ptp/ptpN/n_pins
  51. Date: March 2014
  52. Contact: Richard Cochran <richardcochran@gmail.com>
  53. Description:
  54. This file contains the number of programmable pins
  55. offered by the PTP hardware clock.
  56. What: /sys/class/ptp/ptpN/pins
  57. Date: March 2014
  58. Contact: Richard Cochran <richardcochran@gmail.com>
  59. Description:
  60. This directory contains one file for each programmable
  61. pin offered by the PTP hardware clock. The file name
  62. is the hardware dependent pin name. Reading from this
  63. file produces two numbers, the assigned function (see
  64. the `PTP_PF_` enumeration values in linux/ptp_clock.h)
  65. and the channel number. The function and channel
  66. assignment may be changed by two writing numbers into
  67. the file.
  68. What: /sys/class/ptp/ptpN/pps_available
  69. Date: September 2010
  70. Contact: Richard Cochran <richardcochran@gmail.com>
  71. Description:
  72. This file indicates whether the PTP hardware clock
  73. supports a Pulse Per Second to the host CPU. Reading
  74. "1" means that the PPS is supported, while "0" means
  75. not supported.
  76. What: /sys/class/ptp/ptpN/extts_enable
  77. Date: September 2010
  78. Contact: Richard Cochran <richardcochran@gmail.com>
  79. Description:
  80. This write-only file enables or disables external
  81. timestamps. To enable external timestamps, write the
  82. channel index followed by a "1" into the file.
  83. To disable external timestamps, write the channel
  84. index followed by a "0" into the file.
  85. What: /sys/class/ptp/ptpN/fifo
  86. Date: September 2010
  87. Contact: Richard Cochran <richardcochran@gmail.com>
  88. Description:
  89. This file provides timestamps on external events, in
  90. the form of three integers: channel index, seconds,
  91. and nanoseconds.
  92. What: /sys/class/ptp/ptpN/period
  93. Date: September 2010
  94. Contact: Richard Cochran <richardcochran@gmail.com>
  95. Description:
  96. This write-only file enables or disables periodic
  97. outputs. To enable a periodic output, write five
  98. integers into the file: channel index, start time
  99. seconds, start time nanoseconds, period seconds, and
  100. period nanoseconds. To disable a periodic output, set
  101. all the seconds and nanoseconds values to zero.
  102. What: /sys/class/ptp/ptpN/pps_enable
  103. Date: September 2010
  104. Contact: Richard Cochran <richardcochran@gmail.com>
  105. Description:
  106. This write-only file enables or disables delivery of
  107. PPS events to the Linux PPS subsystem. To enable PPS
  108. events, write a "1" into the file. To disable events,
  109. write a "0" into the file.