From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jani Nikula Subject: Re: [REGRESSION BISECTED] backlight control stops workin with 3.14 and later Date: Mon, 18 Aug 2014 10:37:14 +0300 Message-ID: <87wqa6nt91.fsf@intel.com> References: <53CE07D9.3090308@redhat.com> <53CF7651.4080305@redhat.com> <87d2c4qzdf.fsf@intel.com> <53ED11DD.3040104@sikken.nl> <878umpq36f.fsf@intel.com> <53F06B65.4090001@sikken.nl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id 0B5B86E1E6 for ; Mon, 18 Aug 2014 00:37:18 -0700 (PDT) In-Reply-To: <53F06B65.4090001@sikken.nl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Bertrik Sikken Cc: "intel-gfx@lists.freedesktop.org" List-Id: intel-gfx@lists.freedesktop.org On Sun, 17 Aug 2014, Bertrik Sikken wrote: > On 15-8-2014 3:43, Jani Nikula wrote: >> On Thu, 14 Aug 2014, Bertrik Sikken wrote: > >>> Attached is dmesg output from booting kernel 3.14-2 (debian unstable) >>> with drm.debug=0xe and the samsung_laptop module enabled, from my >>> Samsung N150plus netbook. >> >> Have you tried 3.15? > > I've built the v3.15 kernel (using the .config file from debian > unstable and doing make oldconfig). > > The backlight is at maximum brightness after boot and I can't control > it using the backlight buttons, nor by writing to > /sys/class/backlight/samsung/brightness > (say half the value or 1/10th of max_brightness) > > Backlight does work when writing > /sys/class/backlight/intel_backlight/brightness How about disabling samsung backlight module with 3.15? BR, Jani. > > Kind regards, > Bertrik Sikken -- Jani Nikula, Intel Open Source Technology Center