Re: [RFC PATCH v2 1/5] rtc: migrate driver data to RTC device

[Alexandre Belloni <alexandre.belloni@bootlin.com>]

On 08/01/2026 14:52:08+0100, Danilo Krummrich wrote:
> On Thu Jan 8, 2026 at 2:45 PM CET, Ke Sun wrote:
> >
> > On 1/8/26 19:12, Danilo Krummrich wrote:
> >> On Wed Jan 7, 2026 at 3:37 PM CET, Ke Sun wrote:
> >>> diff --git a/drivers/rtc/dev.c b/drivers/rtc/dev.c
> >>> index baf1a8ca8b2b1..0f62ba9342e3e 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, &param);
> >>> +				err = rtc->ops->param_get(&rtc->dev, &param);
> >> It would make more sense to just pass a struct rtc_device than the embedded
> >> struct device in the RTC callbacks.
> > I considered passing struct rtc_device directly, but chose &rtc->dev
> > to minimize changes to existing drivers, since most callbacks use
> > dev_get_drvdata() on the device parameter.
> 
> No, you should not expose the embedded base device. For accessing the private
> data you should add helpers like rtc_get_drvdata(). This is what other
> subsystems do as well, e.g. [1].
> 
> [1] https://elixir.bootlin.com/linux/v6.18.3/source/include/linux/i2c.h#L371

This is not a correct example as i2c is a bus, just like amba is...
Actually, I don't think the rework is necessary at all or this would
mean we need to rewor most of our existing subsystems.


-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com