Am 2021-04-30 17:19, schrieb Mark Brown:

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

quoted

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...

But creating and using the regmap are two seperate things, no? Consider
the gpio-sl28cpld. It will just use whatever regmap the parent has 
created.
How would it know what type of regmap it is?

quoted

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...

I can't follow you here.

-michael