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Wysocki" References: <20260116162203.296844-1-sunke@kylinos.cn> <20260116162203.296844-2-sunke@kylinos.cn> From: Ke Sun In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/19/26 22:32, Danilo Krummrich wrote: > On Fri Jan 16, 2026 at 5:21 PM CET, Ke Sun wrote: >> diff --git a/drivers/rtc/dev.c b/drivers/rtc/dev.c >> index baf1a8ca8b2b1..eddcc5a69db3b 100644 >> --- a/drivers/rtc/dev.c >> +++ b/drivers/rtc/dev.c >> @@ -410,7 +410,7 @@ static long rtc_dev_ioctl(struct file *file, >> } >> default: >> if (rtc->ops->param_get) >> - err = rtc->ops->param_get(rtc->dev.parent, ¶m); >> + err = rtc->ops->param_get(rtc_ops_dev(rtc), ¶m); >> else >> err = -EINVAL; >> } > > >> +/** >> + * rtc_ops_dev - Get the device pointer for RTC ops callbacks >> + * @rtc: RTC device >> + * >> + * Returns &rtc->dev if RTC_OPS_USE_RTC_DEV flag is set, >> + * otherwise returns rtc->dev.parent. >> + */ >> +static inline struct device *rtc_ops_dev(struct rtc_device *rtc) >> +{ >> + if (test_bit(RTC_OPS_USE_RTC_DEV, &rtc->flags)) >> + return &rtc->dev; >> + return rtc->dev.parent; >> +} > I understand that the idea is to gradually convert all drivers to use the RTC > device, rather than it's parent device in RTC device callbacks. > > My main concern is that once that has been achieved it's still not what we want > to have eventually, i.e. RTC device callbacks should ideally take a struct > rtc_device as argument and not the embedded base struct device. > > I.e. we'd kick off a conversion process that won't reach the actual desired > state. Hi Danilo, This is indeed an intermediate step. Full cleanup is in progress, but it's large and untested. I'm working on a complete cleanup involving ~190+ files across arch/, drivers/rtc/, and drivers/virtio/. Most changes are straightforward interface replacements, but some drivers need additional modifications. Given the scale, I haven't fully tested everything and can't guarantee correctness yet. The intermediate step enables gradual migration, allowing us to: - Clean up and test each rtc driver incrementally - Ensure correctness through gradual changes - Avoid breaking existing functionality Once all cleanup is complete and tested, changing all rtc_class_ops callbacks to use struct rtc_device * will be much simpler and safer. Currently there seem to be only these two approaches. I'm still waiting for Alexandre's suggestion on how to proceed specifically, but haven't received a response yet. Best regard, Ke Sun