iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

docs: ABI: Document new timecard sysfs nodes.

Browse Source 
Add sysfs nodes for the frequency generator and signal counters.

Update SMA selector lists for these, and also add the new
'None', 'VCC' 'GND' selectors.

Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jonathan Lemon 2022-03-10 12:19:12 -08:00 committed by David S. Miller
parent 0fa3ff7eb0
commit ff1d56cb26
1 changed files with 93 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

94
Documentation/ABI/testing/sysfs-timecard
View File

@ -37,8 +37,15 @@ Description: (RO) Set of available destinations (sinks) for a SMA
PPS2 signal is sent to the PPS2 selector
TS1 signal is sent to timestamper 1
TS2 signal is sent to timestamper 2
TS3 signal is sent to timestamper 3
TS4 signal is sent to timestamper 4
IRIG signal is sent to the IRIG-B module
DCF signal is sent to the DCF module
FREQ1 signal is sent to frequency counter 1
FREQ2 signal is sent to frequency counter 2
FREQ3 signal is sent to frequency counter 3
FREQ4 signal is sent to frequency counter 4
None signal input is disabled
===== ================================================
What: /sys/class/timecard/ocpN/available_sma_outputs
@ -50,10 +57,16 @@ Description: (RO) Set of available sources for a SMA output signal.
10Mhz output is from the 10Mhz reference clock
PHC output PPS is from the PHC clock
MAC output PPS is from the Miniature Atomic Clock
GNSS output PPS is from the GNSS module
GNSS1 output PPS is from the first GNSS module
GNSS2 output PPS is from the second GNSS module
IRIG output is from the PHC, in IRIG-B format
DCF output is from the PHC, in DCF format
GEN1 output is from frequency generator 1
GEN2 output is from frequency generator 2
GEN3 output is from frequency generator 3
GEN4 output is from frequency generator 4
GND output is GND
VCC output is VCC
===== ================================================
What: /sys/class/timecard/ocpN/clock_source
@ -75,6 +88,85 @@ Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Contains the current offset value used by the firmware
for internal disciplining of the atomic clock.
What: /sys/class/timecard/ocpN/freqX
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Optional directory containing the sysfs nodes for
frequency counter <X>.
What: /sys/class/timecard/ocpN/freqX/frequency
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Contains the measured frequency over the specified
measurement period.
What: /sys/class/timecard/ocpN/freqX/seconds
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RW) Specifies the number of seconds from 0-255 that the
frequency should be measured over. Write 0 to disable.
What: /sys/class/timecard/ocpN/genX
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Optional directory containing the sysfs nodes for
frequency generator <X>.
What: /sys/class/timecard/ocpN/genX/duty
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Specifies the signal duty cycle as a percentage from 1-99.
What: /sys/class/timecard/ocpN/genX/period
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Specifies the signal period in nanoseconds.
What: /sys/class/timecard/ocpN/genX/phase
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Specifies the signal phase offset in nanoseconds.
What: /sys/class/timecard/ocpN/genX/polarity
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Specifies the signal polarity, either 1 or 0.
What: /sys/class/timecard/ocpN/genX/running
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Either 0 or 1, showing if the signal generator is running.
What: /sys/class/timecard/ocpN/genX/start
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RO) Shows the time in <sec>.<nsec> that the signal generator
started running.
What: /sys/class/timecard/ocpN/genX/signal
Date: March 2022
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>
Description: (RW) Used to start the signal generator, and summarize
the current status.
The signal generator may be started by writing the signal
period, followed by the optional signal values. If the
optional values are not provided, they default to the current
settings, which may be obtained from the other sysfs nodes.
period [duty [phase [polarity]]]
echo 500000000 > signal # 1/2 second period
echo 1000000 40 100 > signal
echo 0 > signal # turn off generator
Period and phase are specified in nanoseconds. Duty cycle is
a percentage from 1-99. Polarity is 1 or 0.
Reading this node will return:
period duty phase polarity start_time
What: /sys/class/timecard/ocpN/gnss_sync
Date: September 2021
Contact: Jonathan Lemon <jonathan.lemon@gmail.com>