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

[Richard Cochran]

On Fri, Jan 09, 2026 at 10:56:56AM +0800, Wen Gu wrote:

> Introducing a new clock type or a new userspace API (e.g. /dev/XXX) would
> require widespread userspace changes, duplicated tooling, and long-term
> fragmentation. This RFC is explicitly NOT proposing a new userspace API.

Actually I disagree.

The PHC devices appear to user space as clockid_t.

The API for these works seamlessly and interchangeably with SYS-V clock IDs.

The path that is opened, whether /dev/ptpX or some new /dev/hwclkX etc
is a trivial detail that adds no burden to user space.

Thanks,
Richard