From patchwork Fri Aug 2 01:16:03 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Lu X-Patchwork-Id: 2837454 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 9BE129F479 for ; Fri, 2 Aug 2013 01:15:30 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2A658202F6 for ; Fri, 2 Aug 2013 01:15:29 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 3F2ED202F1 for ; Fri, 2 Aug 2013 01:15:28 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1656EE5F78 for ; Thu, 1 Aug 2013 18:15:28 -0700 (PDT) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga03.intel.com (mga03.intel.com [143.182.124.21]) by gabe.freedesktop.org (Postfix) with ESMTP id C0352E5BF8; Thu, 1 Aug 2013 18:15:17 -0700 (PDT) Received: from azsmga002.ch.intel.com ([10.2.17.35]) by azsmga101.ch.intel.com with ESMTP; 01 Aug 2013 18:15:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.89,797,1367996400"; d="scan'208";a="276561915" Received: from aaronlu.sh.intel.com ([10.239.36.102]) by AZSMGA002.ch.intel.com with ESMTP; 01 Aug 2013 18:15:15 -0700 Message-ID: <51FB0853.9090105@intel.com> Date: Fri, 02 Aug 2013 09:16:03 +0800 From: Aaron Lu User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130625 Thunderbird/17.0.7 MIME-Version: 1.0 To: Daniel Vetter , Jani Nikula , Borislav Petkov References: <20130731162252.GC4724@pd.tnic> <20130731163623.GD4724@pd.tnic> <51F9B63F.7060509@intel.com> <20130801081215.GB3448@nazgul.tnic> <51FA2537.5040208@intel.com> In-Reply-To: <51FA2537.5040208@intel.com> Cc: "Rafael J. Wysocki" , ACPI Devel Mailing List , intel-gfx@lists.freedesktop.org, lkml , dri-devel@lists.freedesktop.org Subject: Re: [Intel-gfx] i915 backlight X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+patchwork-intel-gfx=patchwork.kernel.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+patchwork-intel-gfx=patchwork.kernel.org@lists.freedesktop.org X-Spam-Status: No, score=-5.7 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On 08/01/2013 05:07 PM, Aaron Lu wrote: > On 08/01/2013 04:12 PM, Borislav Petkov wrote: >> On Thu, Aug 01, 2013 at 09:13:35AM +0800, Aaron Lu wrote: >>> Can you please run acpi_listen and then press the Fn-Fx key, see if the >>> events are correctly sent out? >> >> Like this? >> >> # acpi_listen >> video/brightnessdown BRTDN 00000087 00000000 >> video/brightnessup BRTUP 00000086 00000000 >> video/brightnessdown BRTDN 00000087 00000000 >> video/brightnessup BRTUP 00000086 00000000 >> video/brightnessdown BRTDN 00000087 00000000 >> video/brightnessup BRTUP 00000086 00000000 >> video/brightnessdown BRTDN 00000087 00000000 >> video/brightnessup BRTUP 00000086 00000000 >> video/brightnessdown BRTDN 00000087 00000000 >> ^C > > Yes, so the event is correctly sent out. > >> >>> From the bug page: >>> https://bugzilla.kernel.org/show_bug.cgi?id=51231#c80 >>> I got the impression that both the acpi_video interface and the vendor >>> interface thinkpad_screen are broken. So adding this cmdline here works >>> suggests that either thinkpad_screen works or thinkpad vendor driver >>> doesn't get loaded or doesn't create that interface for some reason. >>> >>> Alternatively, if the intel_backlight interface works(highly possible), >>> you can use xorg.conf to specify the that backlight interface for X. >>> >>> Section "Device" >>> Option "Backlight" "intel_backlight" >>> Identifier "Card0" >>> Driver "intel" >>> BusID "PCI:0:2:0" >>> EndSection >> >> Yeah, that didn't work *but* manually writing to both: >> >> /sys/class/backlight/acpi_video0/brightness >> >> and >> >> /sys/class/backlight/intel_backlight/brightness >> >> works. > > Err...we have the event sent out on hotkey press and the interface also > works, but still, using hotkey to adjust brightness level is broken... > > I just found an old acer laptop that has similar issue(or even worse: on > X starts, an almost black screen is shown and hotkey adjust doesn't > work), I'll look into this. Hi Jani & Daniel, It turned out there is an integer overflow problem, and the below patch fixed this problem on Acer Aspire 4732Z and thinkpad R61i. From: Aaron Lu Subject: [PATCH] drm/i915: avoid brightness overflow when doing scale Some card's max brightness level is pretty large, e.g. on Acer Aspire 4732Z, the max level is 989910. If user space set a large enough level then the current scale done in intel_panel_set_backlight will cause an integer overflow and the scaled level will be mistakenly small, leaving user with an almost black screen. This patch fixes this problem. Signed-off-by: Aaron Lu --- Since the only external user of intel_panel_set_backlight is operation region code where the max will be a constant of 255, this patch fixes the problem by comparing freq and max and then do things accordingly instead of converting to 64 bits. drivers/gpu/drm/i915/intel_panel.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index 67e2c1f..7c674f0 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -498,7 +498,10 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level, u32 max) } /* scale to hardware */ - level = level * freq / max; + if (freq < max) + level = level * freq / max; + else + level = freq / max * level; dev_priv->backlight.level = level; if (dev_priv->backlight.device)