Re: [RFC] Defining a home/maintenance model for non-NIC PHC devices using the /dev/ptpX API

[Wen Gu <guwen@linux.alibaba.com>]

On 2026/1/9 10:56, Wen Gu wrote:
> 
> #
> ## Proposal
> #
> 
> 1. Reorganize drivers/ptp/ to make the interface/implementation split
>     explicit,
> 
>     * drivers/ptp/core      : PTP core infrastructure and API.
>                               (e.g. ptp_chardev.c, ptp_clock.c,
>                                ptp_sysfs.c, etc.)
> 
>     * drivers/ptp/pure      : Non-network ("pure clock") implementation,
>                               they are typically platform/architecture/
>                               virtualization-provided time sources.
>                               (e.g. ptp_kvm, ptp_vmw, ptp_vmclock,
>                                ptp_s390, etc.)
> 
>     * drivers/ptp/*         : Network timestamping oriented implementation,
>                               they primarily used together with IEEE1588
>                               over the network.
>                               (e.g. ptp_qoriq, ptp_pch, ptp_dp83640,
>                                ptp_idt82p33 etc.)
> 

Thanks for the feedback so far. It seems we are close to consensus on
the directory split, as [1] summarized:

- drivers/ptp/core       : PTP core infrastructure and API
- drivers/ptp/1588       : network/IEEE 1588 oriented PTP clocks
- drivers/ptp/emulating  : platform/hardware/hypervisor-provided pure clocks

For how the existing drivers in `drivers/ptp` are categorized into the
directories above, please also refer to [1] and the follow-up replies.

> 2. Transition drivers/ptp/pure from netdev maintainership to
>     clock/time maintainership (with an appropriate MAINTAINERS entry,
>     e.g. PURE TIME PHC), since these PHC implementations are primarily
>     clock devices and not network-oriented. New similar drivers can be
>     added under drivers/ptp/pure as well.


Then the open item now is maintainership and the merge path.

Based on previous guidance[2] and the current MAINTAINERS structure,
it seems reasonable to have it maintained under the clock/timekeeping
domain (following the existing timekeeping pull chain), with a
dedicated MAINTAINERS entry.


Hi Thomas and clock/timekeeping maintainers,

Would you agree with this approach? If so, could you please advise on
the appropriate maintainer/reviewer for this MAINTAINERS entry?

Below is a strawman MAINTAINERS entry (happy to adjust):

EMULATING PTP CLOCK SUPPORT
L:     linux-kernel@vger.kernel.org
S:     Maintained
F:     drivers/ptp/emulating/*


We (Alibaba) are also willing to be the maintainer for this entry as
a fallback.

[1] https://lore.kernel.org/netdev/b5a60753-85ed-4d61-a652-568393e0dff3@linux.alibaba.com/
[2] https://lore.kernel.org/netdev/20251216135848.174e010f@kernel.org/

Regards.