Hi Mark,
On Tue, 14 Apr 2020 at 20:55, Mark Brown broonie@kernel.org wrote:
On Tue, Apr 14, 2020 at 08:20:23PM +0200, Clément Péron wrote:
Hi Liam and Mark,
You might want to flag stuff like this in the subject line, I very nearly deleted this without opening it since most of the email I get about panfrost appears to be coming from me having sent patches rather than being relevant.
Ok will do next time,
We are having an issue with Panfrost driver registering two times the same regulator and giving an error when trying to create the debugfs folder.
Could you clarify if it is allowed for a device to register two times the same regulator?
I check Documentation/power/regulator/regulator.rst but this point is not specified.
We don't actively prevent it and I can't think what other than debugfs might run into problems (and that's just a warning) but it does seem like a weird thing to want to do and like it's pointing to some confusion in your code with two different parts of the device controlling the same supply independently. What's the use case here?
Panfrost first probe clock, reset and regulator in device_init: https://elixir.bootlin.com/linux/v5.7-rc1/source/drivers/gpu/drm/panfrost/pa... Then it probe for optional devfreq, devfreq will get opp tables and also get regulator again. https://elixir.bootlin.com/linux/v5.7-rc1/source/drivers/gpu/drm/panfrost/pa...
That's can be reworked and Panfrost can only probe regulator if there is no opp-table.
But if multiple regulator is not an issue and as each request is logic. The first in device_init assure to enable the regulator and the second in OPP assure the voltage level.
Maybe we can just fix this warning?
Thanks, Clement