What: /sys/class/ptp/ Date: September 2010 Contact: Richard Cochran Description: This directory contains files and directories providing a standardized interface to the ancillary features of PTP hardware clocks. What: /sys/class/ptp/ptp/ Date: September 2010 Contact: Richard Cochran Description: This directory contains the attributes of the Nth PTP hardware clock registered into the PTP class driver subsystem. What: /sys/class/ptp/ptp/clock_name Date: September 2010 Contact: Richard Cochran Description: This file contains the name of the PTP hardware clock as a human readable string. The purpose of this attribute is to provide the user with a "friendly name" and to help distinguish PHY based devices from MAC based ones. The string does not necessarily have to be any kind of unique id. What: /sys/class/ptp/ptp/max_adjustment Date: September 2010 Contact: Richard Cochran Description: This file contains the PTP hardware clock's maximum frequency adjustment value (a positive integer) in parts per billion. What: /sys/class/ptp/ptp/max_vclocks Date: May 2021 Contact: Yangbo Lu Description: This file contains the maximum number of ptp vclocks. Write integer to re-configure it. What: /sys/class/ptp/ptp/n_alarms Date: September 2010 Contact: Richard Cochran Description: This file contains the number of periodic or one shot alarms offer by the PTP hardware clock. What: /sys/class/ptp/ptp/n_external_timestamps Date: September 2010 Contact: Richard Cochran Description: This file contains the number of external timestamp channels offered by the PTP hardware clock. What: /sys/class/ptp/ptp/n_periodic_outputs Date: September 2010 Contact: Richard Cochran Description: This file contains the number of programmable periodic output channels offered by the PTP hardware clock. What: /sys/class/ptp/ptp/n_pins Date: March 2014 Contact: Richard Cochran Description: This file contains the number of programmable pins offered by the PTP hardware clock. What: /sys/class/ptp/ptp/n_vclocks Date: May 2021 Contact: Yangbo Lu Description: This file contains the number of virtual PTP clocks in use. By default, the value is 0 meaning that only the physical clock is in use. Setting the value creates the corresponding number of virtual clocks and causes the physical clock to become free running. Setting the value back to 0 deletes the virtual clocks and switches the physical clock back to normal, adjustable operation. What: /sys/class/ptp/ptp/pins Date: March 2014 Contact: Richard Cochran Description: This directory contains one file for each programmable pin offered by the PTP hardware clock. The file name is the hardware dependent pin name. Reading from this file produces two numbers, the assigned function (see the `PTP_PF_` enumeration values in linux/ptp_clock.h) and the channel number. The function and channel assignment may be changed by two writing numbers into the file. What: /sys/class/ptp/ptp/pps_available Date: September 2010 Contact: Richard Cochran Description: This file indicates whether the PTP hardware clock supports a Pulse Per Second to the host CPU. Reading "1" means that the PPS is supported, while "0" means not supported. What: /sys/class/ptp/ptp/extts_enable Date: September 2010 Contact: Richard Cochran Description: This write-only file enables or disables external timestamps. To enable external timestamps, write the channel index followed by a "1" into the file. To disable external timestamps, write the channel index followed by a "0" into the file. What: /sys/class/ptp/ptp/fifo Date: September 2010 Contact: Richard Cochran Description: This file provides timestamps on external events, in the form of three integers: channel index, seconds, and nanoseconds. What: /sys/class/ptp/ptp/period Date: September 2010 Contact: Richard Cochran Description: This write-only file enables or disables periodic outputs. To enable a periodic output, write five integers into the file: channel index, start time seconds, start time nanoseconds, period seconds, and period nanoseconds. To disable a periodic output, set all the seconds and nanoseconds values to zero. What: /sys/class/ptp/ptp/pps_enable Date: September 2010 Contact: Richard Cochran Description: This write-only file enables or disables delivery of PPS events to the Linux PPS subsystem. To enable PPS events, write a "1" into the file. To disable events, write a "0" into the file.