From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Price Subject: Re: [PATCH] drm/panfrost: Fix regulator_get_optional() misuse Date: Fri, 6 Sep 2019 15:45:11 +0100 Message-ID: <1bfa2b93-301f-22ff-7208-b337b8f3820d@arm.com> References: <20190904123032.23263-1-broonie@kernel.org> <20190905124014.GA4053@sirena.co.uk> <93b8910d-fc01-4c16-fd7e-86abfc3cc617@arm.com> <20190905163420.GD4053@sirena.co.uk> <58594735-c079-74e5-26c8-4911f073d4df@arm.com> <20190906105523.GR23391@sirena.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190906105523.GR23391@sirena.co.uk> Content-Language: en-GB Sender: linux-kernel-owner@vger.kernel.org To: Mark Brown Cc: David Airlie , Tomeu Vizoso , dri-devel , "linux-kernel@vger.kernel.org" List-Id: dri-devel@lists.freedesktop.org On 06/09/2019 11:55, Mark Brown wrote: [...] >>> However you're probably better off hiding all this stuff with the >>> generic OPP code rather than open coding it - this already has much >>> better handling for this, it supports voltage ranges rather than single >>> voltages and optional regulators already. I'm not 100% clear why this >>> is open coded TBH but I might be missing something, if there's some >>> restriction preventing the generic code being used it seems like those >>> sohuld be fixed. > >> To be honest I've no idea how to use the generic OPP code to do this. I >> suspect the original open coding was cargo-culted from another driver: >> the comments in the function look like they were lifted from >> drivers/devfreq/rk3399_dmc.c. Any help tidying this up would be appreciated. > > Yes, there's a lot of cargo culting of bad regulator API usage in > the DRM subsystem for some reason, I keep having to do these > periodic sweeps and there's always stuff in there. I think a lot > of it comes from BSP code that just gets dropped in without > review and then cut'n'pasted but I've not figured out why DRM is > so badly affected. I've been working on tidying up the devfreq usage in Panfrost. From what I can see your patch is correct and I just needed to work out how to fix my DT. Steve