Changes in Kconfig

18ec5491 - ptp: Remove 'default y' for VMCLOCK PTP device

Sat, 02 Nov 2024 21:52:17 +0000

ptp: Remove 'default y' for VMCLOCK PTP deviceThe VMCLOCK device gives support for accurate timekeeping even acrosslive migration, unlike the KVM PTP clock. To help ensure that users canalways use ptp_vmclock where it's available in preference to ptp_kvm,set it to 'default PTP_1588_CLOCK_VMCLOCK' instead of 'default y'.Signed-off-by: David Woodhouse Link: https://patch.msgid.link/89955b74d225129d6e3d79b53aa8d81d1b50560f.camel@infradead.orgSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

2d7de7a3 - s390/time: Add PtP driver

Wed, 23 Oct 2024 06:56:01 +0000

s390/time: Add PtP driverAdd a small PtP driver which allows user space to getthe values of the physical and tod clock. This allowsprograms like chrony to use STP as clock source andsteer the kernel clock. The physical clock can be usedas a debugging aid to get the clock without any additionaloffsets like STP steering or LPAR offset.Acked-by: Heiko Carstens Acked-by: Richard Cochran Signed-off-by: Sven Schnelle Link: https://patch.msgid.link/20241023065601.449586-3-svens@linux.ibm.comSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

20503272 - ptp: Add support for the AMZNC10C 'vmclock' device

Sun, 06 Oct 2024 07:17:58 +0000

ptp: Add support for the AMZNC10C 'vmclock' deviceThe vmclock device addresses the problem of live migration withprecision clocks. The tolerances of a hardware counter (e.g. TSC) aretypically around ±50PPM. A guest will use NTP/PTP/PPS to discipline thatcounter against an external source of 'real' time, and track the precisefrequency of the counter as it changes with environmental conditions.When a guest is live migrated, anything it knows about the frequency ofthe underlying counter becomes invalid. It may move from a host wherethe counter running at -50PPM of its nominal frequency, to a host whereit runs at +50PPM. There will also be a step change in the value of thecounter, as the correctness of its absolute value at migration islimited by the accuracy of the source and destination host's timesynchronization.In its simplest form, the device merely advertises a 'disruption_marker'which indicates that the guest should throw away any NTP synchronizationit thinks it has, and start again.Because the shared memory region can be exposed all the way to userspacethrough the /dev/vmclock0 node, applications can still use time from afast vDSO 'system call', and check the disruption marker to be sure thattheir timestamp is indeed truthful.The structure also allows for the precise time, as known by the host, tobe exposed directly to guests so that they don't have to wait for NTP toresync from scratch. The PTP driver consumes this information if present.Like the KVM PTP clock, this PTP driver can convert TSC-based crosstimestamps into KVM clock values. Unlike the KVM PTP clock, it does soonly when such is actually helpful.The values and fields are based on the nascent virtio-rtc specification,and the intent is that a version (hopefully precisely this version) ofthis structure will be included as an optional part of that spec. In themeantime, this driver supports the simple ACPI form of the device whichis being shipped in certain commercial hypervisors (and submitted forinclusion in QEMU).Signed-off-by: David Woodhouse Acked-by: Richard Cochran Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

1ddfecaf - ptp: add FemtoClock3 Wireless as ptp hardware clock

Wed, 24 Jan 2024 18:49:47 +0000

ptp: add FemtoClock3 Wireless as ptp hardware clockThe RENESAS FemtoClock3 Wireless is a high-performance jitter attenuator,frequency translator, and clock synthesizer. The device is comprised of 3digital PLLs (DPLL) to track CLKIN inputs and three independent low phasenoise fractional output dividers (FOD) that output low phase noise clocks.FemtoClock3 supports one Time Synchronization (Time Sync) channel to enablean external processor to control the phase and frequency of the Time Syncchannel and to take phase measurements using the TDC. Intended applicationsare synchronization using the precision time protocol (PTP) andsynchronization with 0.5 Hz and 1 Hz signals from GNSS.Signed-off-by: Min Li Acked-by: Lee Jones Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

09eeb3ae - ptp_ocp: implement DPLL ops

Wed, 13 Sep 2023 20:49:42 +0000

ptp_ocp: implement DPLL opsImplement basic DPLL operations in ptp_ocp driver as thesimplest example of using new subsystem.Signed-off-by: Vadim Fedorenko Signed-off-by: Arkadiusz Kubalewski Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

40b0425f - net: ptp: create a mock-up PTP Hardware Clock driver

Mon, 07 Aug 2023 19:33:19 +0000

net: ptp: create a mock-up PTP Hardware Clock driverThere are several cases where virtual net devices may benefit fromhaving a PTP clock, and these have to do with testing. I can see atleast netdevsim and veth as potential users of a common mock-up PTPhardware clock driver.The proposed idea is to create an object which emulates PTP clockoperations on top of the unadjustable CLOCK_MONOTONIC_RAW plus asoftware-controlled time domain via a timecounter/cyclecounter and thenlink that PHC to the netdevsim device.The driver is fully functional for its intended purpose, and itsuccessfully passes the PTP selftests.$ cd tools/testing/selftests/ptp/$ ./phc.sh /dev/ptp2TEST: settime [ OK ]TEST: adjtime [ OK ]TEST: adjfreq [ OK ]Signed-off-by: Vladimir Oltean Link: https://lore.kernel.org/r/20230807193324.4128292-7-vladimir.oltean@nxp.comSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

c8cc2ae2 - net: pch_gbe: Allow build on MIPS_GENERIC kernel

Wed, 07 Jun 2023 05:59:53 +0000

net: pch_gbe: Allow build on MIPS_GENERIC kernelMIPS Boston board, which is using MIPS_GENERIC kernel is usingEG20T PCH and thus need this driver.Dependency of PCH_GBE, PTP_1588_CLOCK_PCH is also fixed forMIPS_GENERIC.Note that CONFIG_PCH_GBE is selected in arch/mips/configs/generic/board-boston.config for a while, some how it's never wired upin Kconfig.Signed-off-by: Jiaxun Yang Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20230607055953.34110-1-jiaxun.yang@flygoat.comSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

615927f1 - ptp: add ToD device driver for Intel FPGA cards

Tue, 28 Mar 2023 14:24:55 +0000

ptp: add ToD device driver for Intel FPGA cardsAdding a DFL (Device Feature List) device driver of ToD device forIntel FPGA cards.The Intel FPGA Time of Day(ToD) IP within the FPGA DFL bus is exposedas PTP Hardware clock(PHC) device to the Linux PTP stack to synchronizethe system clock to its ToD information using phc2sys utility of theLinux PTP stack. The DFL is a hardware List within FPGA, which definesa linked list of feature headers within the device MMIO space to providean extensible way of adding subdevice features.Signed-off-by: Raghavendra Khadatare Signed-off-by: Tianfei Zhang Acked-by: Richard Cochran Reviewed-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20230328142455.481146-1-tianfei.zhang@intel.comSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

0c104556 - ptp: ocp: Select CRC16 in the Kconfig.

Tue, 26 Jul 2022 22:06:04 +0000

ptp: ocp: Select CRC16 in the Kconfig.The crc16() function is used to check the firmware validity, butthe library was not explicitly selected.Fixes: 3c3673bde50c ("ptp: ocp: Add firmware header checks")Reported-by: kernel test robot Signed-off-by: Jonathan Lemon Acked-by: Vadim Fedorenko Link: https://lore.kernel.org/r/20220726220604.1339972-1-jonathan.lemon@gmail.comSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

42a99a0b - ptp: ocp: add COMMON_CLK dependency

Mon, 20 Sep 2021 09:57:49 +0000

ptp: ocp: add COMMON_CLK dependencyWithout CONFIG_COMMON_CLK, this fails to link:arm-linux-gnueabi-ld: drivers/ptp/ptp_ocp.o: in function `ptp_ocp_register_i2c':ptp_ocp.c:(.text+0xcc0): undefined reference to `__clk_hw_register_fixed_rate'arm-linux-gnueabi-ld: ptp_ocp.c:(.text+0xcf4): undefined reference to `devm_clk_hw_register_clkdev'arm-linux-gnueabi-ld: drivers/ptp/ptp_ocp.o: in function `ptp_ocp_detach':ptp_ocp.c:(.text+0x1c24): undefined reference to `clk_hw_unregister_fixed_rate'Fixes: a7e1abad13f3 ("ptp: Add clock driver for the OpenCompute TimeCard.")Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

bc8e05d6 - ptp: ocp: Simplify Kconfig.

Wed, 25 Aug 2021 21:17:33 +0000

ptp: ocp: Simplify Kconfig.Remove the 'imply' statements, these apparently are not doingwhat I expected. Platform modules which are used by the driverstill need to be enabled in the overall config for them to beused, but there isn't a hard dependency on them.Use 'depend' for selectable modules which provide functionsused directly by the driver.Signed-off-by: Jonathan Lemon Reviewed-by: Arnd Bergmann Reviewed-by: Randy Dunlap Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

d79500e6 - ptp: ocp: Have Kconfig select NET_DEVLINK

Mon, 16 Aug 2021 22:13:36 +0000

ptp: ocp: Have Kconfig select NET_DEVLINKNET doesn't imply NET_DEVLINK. Select this separately, so thatrandom config combinations don't complain.Reported-by: kernel test robot Fixes: 773bda964921 ("ptp: ocp: Expose various resources on the timecard.")Signed-off-by: Jonathan Lemon Signed-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

944f5101 - ptp: ocp: don't allow on S390

Fri, 13 Aug 2021 20:30:26 +0000

ptp: ocp: don't allow on S390Fix kconfig warning on arch/s390/:WARNING: unmet direct dependencies detected for SERIAL_8250 Depends on [n]: TTY [=y] && HAS_IOMEM [=y] && !S390 [=y] Selected by [m]: - PTP_1588_CLOCK_OCP [=m] && PTP_1588_CLOCK [=m] && HAS_IOMEM [=y] && PCI [=y] && SPI [=y] && I2C [=m] && MTD [=m]Signed-off-by: Randy Dunlap Cc: Richard Cochran Cc: Jonathan Lemon Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

55c8fca1 - ptp_pch: Restore dependency on PCI

Fri, 13 Aug 2021 17:33:27 +0000

ptp_pch: Restore dependency on PCIDuring the swap dependency on PCH_GBE to selection PTP_1588_CLOCK_PCHincidentally dropped the implicit dependency on the PCI. Restore it.Fixes: 18d359ceb044 ("pch_gbe, ptp_pch: Fix the dependency direction between these drivers")Reported-by: kernel test robot Signed-off-by: Andy Shevchenko Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

e5f31552 - ethernet: fix PTP_1588_CLOCK dependencies

Thu, 12 Aug 2021 18:33:58 +0000

ethernet: fix PTP_1588_CLOCK dependenciesThe 'imply' keyword does not do what most people think it does, it onlypolitely asks Kconfig to turn on another symbol, but does not preventit from being disabled manually or built as a loadable module when theuser is built-in. In the ICE driver, the latter now causes a link failure:aarch64-linux-ld: drivers/net/ethernet/intel/ice/ice_main.o: in function `ice_eth_ioctl':ice_main.c:(.text+0x13b0): undefined reference to `ice_ptp_get_ts_config'ice_main.c:(.text+0x13b0): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `ice_ptp_get_ts_config'aarch64-linux-ld: ice_main.c:(.text+0x13bc): undefined reference to `ice_ptp_set_ts_config'ice_main.c:(.text+0x13bc): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `ice_ptp_set_ts_config'aarch64-linux-ld: drivers/net/ethernet/intel/ice/ice_main.o: in function `ice_prepare_for_reset':ice_main.c:(.text+0x31fc): undefined reference to `ice_ptp_release'ice_main.c:(.text+0x31fc): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `ice_ptp_release'aarch64-linux-ld: drivers/net/ethernet/intel/ice/ice_main.o: in function `ice_rebuild':This is a recurring problem in many drivers, and we have discussedit several times befores, without reaching a consensus. I'm providinga link to the previous email thread for reference, which discussessome related problems.To solve the dependency issue better than the 'imply' keyword, introduce aseparate Kconfig symbol "CONFIG_PTP_1588_CLOCK_OPTIONAL" that any drivercan depend on if it is able to use PTP support when available, but worksfine without it. Whenever CONFIG_PTP_1588_CLOCK=m, those drivers arethen prevented from being built-in, the same way as with a 'depends onPTP_1588_CLOCK || !PTP_1588_CLOCK' dependency that does the same trick,but that can be rather confusing when you first see it.Since this should cover the dependencies correctly, the IS_REACHABLE()hack in the header is no longer needed now, and can be turned backinto a normal IS_ENABLED() check. Any driver that gets the dependencywrong will now cause a link time failure rather than being unable to usePTP support when that is in a loadable module.However, the two recently added ptp_get_vclocks_index() andptp_convert_timestamp() interfaces are only called from builtin code withethtool and socket timestamps, so keep the current behavior by stubbingthose out completely when PTP is in a loadable module. This should beaddressed properly in a follow-up.As Richard suggested, we may want to actually turn PTP support into a'bool' option later on, preventing it from being a loadable modulealtogether, which would be one way to solve the problem with the ethtoolinterface.Fixes: 06c16d89d2cb ("ice: register 1588 PTP clock device object for E810 devices")Link: https://lore.kernel.org/netdev/20210804121318.337276-1-arnd@kernel.org/Link: https://lore.kernel.org/netdev/CAK8P3a06enZOf=XyZ+zcAwBczv41UuCTz+=0FMf2gBz1_cOnZQ@mail.gmail.com/Link: https://lore.kernel.org/netdev/CAK8P3a3=eOxE-K25754+fB_-i_0BZzf9a9RfPTX3ppSwu9WZXw@mail.gmail.com/Link: https://lore.kernel.org/netdev/20210726084540.3282344-1-arnd@kernel.org/Acked-by: Shannon Nelson Acked-by: Jacob Keller Acked-by: Richard Cochran Reviewed-by: Vladimir Oltean Signed-off-by: Arnd Bergmann Link: https://lore.kernel.org/r/20210812183509.1362782-1-arnd@kernel.orgSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

773bda96 - ptp: ocp: Expose various resources on the timecard.

Wed, 04 Aug 2021 03:33:27 +0000

ptp: ocp: Expose various resources on the timecard.The OpenCompute timecard driver has additional functionality besidesa clock. Make the following resources available: - The external timestamp channels (ts0/ts1) - devlink support for flashing and health reporting - GPS and MAC serial ports - board serial number (obtained from i2c device)Also add watchdog functionality for when GNSS goes into holdover.The resources are collected under a timecard class directory: [jlemon@timecard ~]$ ls -g /sys/class/timecard/ocp1/ total 0 -r--r--r--. 1 root 4096 Aug 3 19:49 available_clock_sources -rw-r--r--. 1 root 4096 Aug 3 19:49 clock_source lrwxrwxrwx. 1 root 0 Aug 3 19:49 device -> ../../../0000:04:00.0/ -r--r--r--. 1 root 4096 Aug 3 19:49 gps_sync lrwxrwxrwx. 1 root 0 Aug 3 19:49 i2c -> ../../xiic-i2c.1024/i2c-2/ drwxr-xr-x. 2 root 0 Aug 3 19:49 power/ lrwxrwxrwx. 1 root 0 Aug 3 19:49 pps -> ../../../../../virtual/pps/pps1/ lrwxrwxrwx. 1 root 0 Aug 3 19:49 ptp -> ../../ptp/ptp2/ -r--r--r--. 1 root 4096 Aug 3 19:49 serialnum lrwxrwxrwx. 1 root 0 Aug 3 19:49 subsystem -> ../../../../../../class/timecard/ lrwxrwxrwx. 1 root 0 Aug 3 19:49 ttyGPS -> ../../tty/ttyS7/ lrwxrwxrwx. 1 root 0 Aug 3 19:49 ttyMAC -> ../../tty/ttyS8/ -rw-r--r--. 1 root 4096 Aug 3 19:39 ueventThe labeling is needed at the minimum, in order to tell the serialdevices apart.Signed-off-by: Jonathan Lemon Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

300bb1fe - ptp: arm/arm64: Enable ptp_kvm for arm/arm64

Wed, 09 Dec 2020 06:09:30 +0000

ptp: arm/arm64: Enable ptp_kvm for arm/arm64Currently, there is no mechanism to keep time sync between guest and hostin arm/arm64 virtualization environment. Time in guest will drift comparedwith host after boot up as they may both use third party time sourcesto correct their time respectively. The time deviation will be in orderof milliseconds. But in some scenarios,like in cloud environment, we askfor higher time precision.kvm ptp clock, which chooses the host clock source as a referenceclock to sync time between guest and host, has been adopted by x86which takes the time sync order from milliseconds to nanoseconds.This patch enables kvm ptp clock for arm/arm64 and improves clock sync precisionsignificantly.Test result comparisons between with kvm ptp clock and without it in arm/arm64are as follows. This test derived from the result of command 'chronycsources'. we should take more care of the last sample column which showsthe offset between the local clock and the source at the last measurement.no kvm ptp in guest:MS Name/IP address Stratum Poll Reach LastRx Last sample========================================================================^* dns1.synet.edu.cn 2 6 377 13 +1040us[+1581us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 21 +1040us[+1581us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 29 +1040us[+1581us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 37 +1040us[+1581us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 45 +1040us[+1581us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 53 +1040us[+1581us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 61 +1040us[+1581us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 4 -130us[ +796us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 12 -130us[ +796us] +/- 21ms^* dns1.synet.edu.cn 2 6 377 20 -130us[ +796us] +/- 21msin host:MS Name/IP address Stratum Poll Reach LastRx Last sample========================================================================^* 120.25.115.20 2 7 377 72 -470us[ -603us] +/- 18ms^* 120.25.115.20 2 7 377 92 -470us[ -603us] +/- 18ms^* 120.25.115.20 2 7 377 112 -470us[ -603us] +/- 18ms^* 120.25.115.20 2 7 377 2 +872ns[-6808ns] +/- 17ms^* 120.25.115.20 2 7 377 22 +872ns[-6808ns] +/- 17ms^* 120.25.115.20 2 7 377 43 +872ns[-6808ns] +/- 17ms^* 120.25.115.20 2 7 377 63 +872ns[-6808ns] +/- 17ms^* 120.25.115.20 2 7 377 83 +872ns[-6808ns] +/- 17ms^* 120.25.115.20 2 7 377 103 +872ns[-6808ns] +/- 17ms^* 120.25.115.20 2 7 377 123 +872ns[-6808ns] +/- 17msThe dns1.synet.edu.cn is the network reference clock for guest and120.25.115.20 is the network reference clock for host. we can't get theclock error between guest and host directly, but a roughly estimated valuewill be in order of hundreds of us to ms.with kvm ptp in guest:chrony has been disabled in host to remove the disturb by network clock.MS Name/IP address Stratum Poll Reach LastRx Last sample========================================================================* PHC0 0 3 377 8 -7ns[ +1ns] +/- 3ns* PHC0 0 3 377 8 +1ns[ +16ns] +/- 3ns* PHC0 0 3 377 6 -4ns[ -0ns] +/- 6ns* PHC0 0 3 377 6 -8ns[ -12ns] +/- 5ns* PHC0 0 3 377 5 +2ns[ +4ns] +/- 4ns* PHC0 0 3 377 13 +2ns[ +4ns] +/- 4ns* PHC0 0 3 377 12 -4ns[ -6ns] +/- 4ns* PHC0 0 3 377 11 -8ns[ -11ns] +/- 6ns* PHC0 0 3 377 10 -14ns[ -20ns] +/- 4ns* PHC0 0 3 377 8 +4ns[ +5ns] +/- 4nsThe PHC0 is the ptp clock which choose the host clock as its sourceclock. So we can see that the clock difference between host and guestis in order of ns.Cc: Mark Rutland Acked-by: Richard Cochran Signed-off-by: Jianyong Wu Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20201209060932.212364-8-jianyong.wu@arm.com List of files: /linux-6.15/drivers/ptp/Kconfig

1f685e6a - ptp: ptp_ines: prevent build when HAS_IOMEM is not set

Wed, 06 Jan 2021 04:25:31 +0000

ptp: ptp_ines: prevent build when HAS_IOMEM is not setptp_ines.c uses devm_platform_ioremap_resource(), which is onlybuilt/available when CONFIG_HAS_IOMEM is enabled.CONFIG_HAS_IOMEM is not enabled for arch/s390/, so builds on S390have a build error:s390-linux-ld: drivers/ptp/ptp_ines.o: in function `ines_ptp_ctrl_probe':ptp_ines.c:(.text+0x17e6): undefined reference to `devm_platform_ioremap_resource'Prevent builds of ptp_ines.c when HAS_IOMEM is not set.Fixes: bad1eaa6ac31 ("ptp: Add a driver for InES time stamping IP core.")Signed-off-by: Randy Dunlap Reported-by: kernel test robot Link: lore.kernel.org/r/202101031125.ZEFCUiKi-lkp@intel.comAcked-by: Richard Cochran Link: https://lore.kernel.org/r/20210106042531.1351-1-rdunlap@infradead.orgSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig

f9d6f941 - phy: dp83640: select CONFIG_CRC32

Sun, 03 Jan 2021 21:36:18 +0000

phy: dp83640: select CONFIG_CRC32Without crc32, this driver fails to link:arm-linux-gnueabi-ld: drivers/net/phy/dp83640.o: in function `match':dp83640.c:(.text+0x476c): undefined reference to `crc32_le'Fixes: 539e44d26855 ("dp83640: Include hash in timestamp/packet matching")Signed-off-by: Arnd Bergmann Reviewed-by: Andrew Lunn Acked-by: Richard Cochran Signed-off-by: David S. Miller List of files: /linux-6.15/drivers/ptp/Kconfig

a7e1abad - ptp: Add clock driver for the OpenCompute TimeCard.

Fri, 04 Dec 2020 03:51:28 +0000

ptp: Add clock driver for the OpenCompute TimeCard.The OpenCompute time card is an atomic clock along witha GPS receiver that provides a Grandmaster clock sourcefor a PTP enabled network.More information is available at http://www.timingcard.com/Signed-off-by: Jonathan Lemon Acked-by: Richard Cochran Link: https://lore.kernel.org/r/20201204035128.2219252-2-jonathan.lemon@gmail.comSigned-off-by: Jakub Kicinski List of files: /linux-6.15/drivers/ptp/Kconfig