On Mon, Jul 19, 2021 at 03:53:38PM +0200, Matthias Schiffer wrote:

> With recent kernels (observed on v5.10.y, but the code doesn't look
> significantly different on master/next) I've seen the following message
> on boot on i.MX6UL SoCs:

That's not recent but anyway...

> It seems to me that there is no correct way to use regmap_attach_dev()
> from outside of __regmap_init(). In particular on a syscon regmap that
> may be shared between different drivers, setting map->dev looks wrong
> to me.

Yes, trying to set the device on a regmap that already has a device is
not a good idea, if the syscon code is doing it transparently as part of
lookup then syscon users shouldn't do it by hand.