From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: Tegra DRM with HDMI support (\o/) Date: Tue, 16 Oct 2012 10:03:56 -0600 Message-ID: <507D856C.1070708@wwwdotorg.org> References: <20121011200705.GB27599@avionic-0098.mockup.avionic-design.de> <1350375538.2332.31.camel@markz-hp6200> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1350375538.2332.31.camel@markz-hp6200> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: markz-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org Cc: Thierry Reding , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-tegra@vger.kernel.org On 10/16/2012 02:18 AM, Mark Zhang wrote: > Hi, > > I've made this drm driver worked on Tegra 3(LVDS and HDMI both). > But the code that Thierry > hosts(git://gitorious.org/thierryreding/linux.git) doesn't work > directly. If you build and run it, you'll get a white blank screen on > Tegra 3. I didn't find the root cause but I think this is not caused by > drm driver itself(maybe the PCIE codes?). The main symptom is: some > regulators can't be inited all the time. I tried to build drm driver as > kernel module, after kernel booted, modprobe the drm driver, and you'll > find there are a lot of error prints like this: > > ========================================================= > [ 21.383529] reg-fixed-voltage 1.regulator: Failed to find supply vin > [ 21.390299] reg-fixed-voltage 1.regulator: Failed to register > regulator: -517 > [ 21.397645] platform 1.regulator: Driver reg-fixed-voltage requests > probe deferral > [ 21.405604] platform 2.regulator: Driver reg-fixed-voltage requests > probe deferral > ========================================================= This is normal; it's probe deferral. You'll find that those regulators initialize correctly later. Hopefully tegra-drm handles this correctly, and passes that error code through as the result of its probe.