[RFC 1/9] regmap: Add USB support

[Mark Brown]

On Mon, Feb 17, 2020 at 11:15:37PM +0100, Noralf Trønnes wrote:
> Den 17.02.2020 22.39, skrev Mark Brown:

> > Out of interest why are 8 bit registers going to be a problem?

> I have written 3 drivers so far and they all have some registers that
> need to deal with values larger than 255. If I would need to add a lot
> of code because of dropping regmap, then I would have looked at ways to
> work around this in order to keep regmap, hi/lo registers perhaps with
> wrapping access functions. But it looks like the LOC won't change much,
> I need a few lines to ensure values are little endian, but I can also
> remove some lines that's not needed anymore.

Right, so you effectively have mixed register sizes which regmap isn't
going to be super happy with (assuming you need all the actual display
data to be 8 bit "registers").  One thing you could do there if you
wanted to try the regmap route is to have multiple regmaps but since
it's not clear what you're really getting from regmap other than the
trace functionality you're probably right that it's not worth bothering.

The only other thing I can think of is packing RGB into a single
register so you're display data isn't 8 bit but that's probably not
sensible from a graphics point of view (I didn't really look at that
code so no idea what you're doing there).
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/dri-devel/attachments/20200217/e0ce989e/attachment.sig>