On Fri, Apr 30, 2021 at 03:06:44PM +0200, Michael Walle wrote:

> Sometimes a driver needs to know if the underlying regmap could sleep.
> For example, consider the gpio-regmap driver which needs to fill the
> gpiochip->can_sleep property.

Whatever is creating the regmap really ought to know what device it's
dealing with...

> It might be possible to pass this information via the
> gpio_regmap_config, but this has the following drawbacks. First, that
> property is redundant and both places might contratict each other. And
> secondly, the driver might not even know the type of the regmap because
> it just gets an opaque pointer by querying the device tree.

If it's a generic GPIO driver from a code correctness point of view it's
always got a risk of sleeping...