From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH 1/2] drm/i915: clear up backlight inversion confusion on gen4 Date: Mon, 23 Apr 2012 14:36:19 +0200 Message-ID: <20120423123619.GF4935@phenom.ffwll.local> References: <1335173535-14811-1-git-send-email-daniel.vetter@ffwll.ch> <4F9542EF.3010208@osadl.org> <20120423123257.GE4935@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ee0-f49.google.com (mail-ee0-f49.google.com [74.125.83.49]) by gabe.freedesktop.org (Postfix) with ESMTP id 68F7E9E796 for ; Mon, 23 Apr 2012 05:35:20 -0700 (PDT) Received: by eekb45 with SMTP id b45so3105938eek.36 for ; Mon, 23 Apr 2012 05:35:19 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20120423123257.GE4935@phenom.ffwll.local> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Carsten Emde Cc: Daniel Vetter , Intel Graphics Development List-Id: intel-gfx@lists.freedesktop.org On Mon, Apr 23, 2012 at 02:32:57PM +0200, Daniel Vetter wrote: > On Mon, Apr 23, 2012 at 01:54:23PM +0200, Carsten Emde wrote: > > On 04/23/2012 11:32 AM, Daniel Vetter wrote: > > >There's a bit in the docs for gen4 only that says whether the > > >backlight control is inverted. And both the quirk we have and > > >all bugs only concern i965gm and gm45 (and mostly Acer) afaics. > > > > > >So lets drop the quirk and use the bit instead. > > > > > >Also clean up the BLC register definitions a bit by correctly > > >grouping the CTL and CTL2 definitions together. > > >[..] > > >diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c > > >index 4c844c6..5d215f0 100644 > > >--- a/drivers/gpu/drm/i915/intel_display.c > > >+++ b/drivers/gpu/drm/i915/intel_display.c > > >@@ -6482,9 +6482,6 @@ static struct intel_quirk intel_quirks[] = { > > > > > > /* Sony Vaio Y cannot use SSC on LVDS */ > > > { 0x0046, 0x104d, 0x9076, quirk_ssc_force_disable }, > > >- > > >- /* Acer Aspire 5734Z must invert backlight brightness */ > > >- { 0x2a42, 0x1025, 0x0459, quirk_invert_brightness }, > > Made a first test with these lines removed and the new mechanism > > added. Unfortunately, the screen is now dark again. Works after > > re-adding the quirk. > > > > >+ /* gen4 has a polarity bit */ > > >+ if (IS_GEN4(dev) && (I915_READ(BLC_PWM_CTL2) & BLM_POLARITY_I965)) > > >+ return intel_panel_get_max_backlight(dev) - val; > > >+ > > Apparently, these conditions are not met on the Acer Aspire 5734Z. > > Will add some debug output and evaluate further. For the time being, > > please leave the quirk in place. > > Hm, I've tried this and when I set this bit, panel brightness is inverted > on my gm45. Can you install intel-gpu-tools and read out the 2 backlight > control registers with > > # intel_reg_read 0x61254 > # intel_reg_read 0x61250 I've forgotten to add: Also please grab these register values when booting with nomodeset, so that we can compare the values the bios sets with whatever i915 sets. -Daniel -- Daniel Vetter Mail: daniel@ffwll.ch Mobile: +41 (0)79 365 57 48