Re: [PATCH] net: cpts: Condition WARN_ON on PTP_1588_CLOCK

From: Richard Cochran
Date: Mon Apr 20 2020 - 13:00:57 EST


On Mon, Apr 20, 2020 at 04:38:32PM +0200, Arnd Bergmann wrote:
>
> I suspect we should move all of them back. This was an early user
> of 'imply', but the meaning of that keyword has now changed
> in the latest Kconfig.

Can you please explain the justification for changing the meaning?

It was a big PITA for me to support this in the first place, and now
we are back to square one?

> Something else is wrong if you need IS_ERR_OR_NULL(). Any
> kernel interface should either return an negative error code when
> something goes wrong, or should return NULL for all errors, but
> not mix the two.

On the contrary, this is exactly what the whole "imply" thing
demanded.

d1cbfd771ce82 (Nicolas Pitre 2016-11-11 172) #if IS_REACHABLE(CONFIG_PTP_1588_CLOCK)
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 173)
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 174) /**
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 175) * ptp_clock_register() - register a PTP hardware clock driver
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 176) *
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 177) * @info: Structure describing the new clock.
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 178) * @parent: Pointer to the parent device of the new clock.
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 179) *
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 180) * Returns a valid pointer on success or PTR_ERR on failure. If PHC
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 181) * support is missing at the configuration level, this function
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 182) * returns NULL, and drivers are expected to gracefully handle that
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 183) * case separately.
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 184) */
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 185)
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 186) extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
d1cbfd771ce82 (Nicolas Pitre 2016-11-11 187) struct device *parent);

Thanks,
Richard