From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julian Wollrath Subject: Re: [Regression]: Changing brightness does not work with v3.16-rc4 Date: Mon, 14 Jul 2014 14:42:27 +0200 Message-ID: <20140714144227.1f270b6c@saldaea> References: <20140712180636.698e2e4c@saldaea> <53C33B1D.4070500@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from mout.web.de ([212.227.17.12]:54812 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754564AbaGNMmb (ORCPT ); Mon, 14 Jul 2014 08:42:31 -0400 In-Reply-To: <53C33B1D.4070500@intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Aaron Lu Cc: linux-acpi@vger.kernel.org Hi, Am Mon, 14 Jul 2014 10:06:21 +0800 schrieb Aaron Lu : > > changing the brightness on my Thinkpad X230 with Intel HD4000 > > graphics, stopped working after commit 886129a8eebe (ACPI / video: > > change acpi-video brightness_switch_enabled default to 0). Changing > > it back to 1, fixes the problem, if "acpi_osi=!Windows 2012" is > > also set. Before that commit just setting "acpi_osi=!Windows 2012" > > was enough to get changing the brightness working. > > Does your system have /sys/class/backlight/intel_backlight? Does it > work if you manually change the brightness file like this: > # cd /sys/class/backlight/intel_backlight > # cat max_brightness > xxxxx > # echo xxx > brightness > # echo xxx > brightness > ... yes, my system has /sys/class/backlight/intel_backlight and changing the brightness works with writing to the "brightness"-file. Cheers, Julian