From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752742Ab3LBBtc (ORCPT ); Sun, 1 Dec 2013 20:49:32 -0500 Received: from nm18-vm0.bullet.mail.bf1.yahoo.com ([98.139.213.138]:33562 "HELO nm18-vm0.bullet.mail.bf1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752449Ab3LBBta convert rfc822-to-8bit (ORCPT ); Sun, 1 Dec 2013 20:49:30 -0500 X-Greylist: delayed 342 seconds by postgrey-1.27 at vger.kernel.org; Sun, 01 Dec 2013 20:49:30 EST X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 992885.11252.bm@omp1057.mail.bf1.yahoo.com DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Rocket-MIMEInfo:X-Mailer:Message-ID:Date:From:Reply-To:Subject:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding; b=tJiB43OVm3dqxiY8ghpG/piycJBahqE+37hLKEOALSAS9J3LKPydOFCuYVcYOT4PwI/PasC062gxsJRkG3H0zrmLPcudVfRkv2nwGX/LhEftDri67D1zavHnriXwLQ7poSaXlfJoVWhlQdDF/GBMmQ3evqB3c6391li2dCoUbOk=; X-YMail-OSG: Pu3_AeMVM1lZhF5fYVbetYsRZT0OJG3b.WVK0Jlox6_BwSh IGu084HCFFZWzcKGuY8FkhRd4CtDQ5EljN4pmvwfolfshRCDfQrShrEKJ_n5 fdSTf9Pe1jtu57fMUDnOPvxYf_952fiM7QEae9NLZGVzf8fEpQaC4LrF.czp MzByzA1Ry9hV0Zg6aiI0uBV0pN0sg6Fv2zdSkSR6iM5H9kptubhOjb67ouIA XZ_rWxxEDaYPErfh42HsxizubbvV5uea2jSAls8o03D7s0pA.sRHSMuSWO4l Dc2j6wLcp5mai0UV0b_9an0BHCarhTB1QfevY2yRb2GIe0n0KcHVOzBPJveP UH9HyBrx8goaupk7M69nI06NEP86bh4jL32xby9RSNNUSjB.iD_fedLg076a kHTVS8S_AOdddjAkoZiBBUgrgvQY9pwLkka7e2HF9fHTiBcjT4pMVnP2uumu wmY0xkqNLGP7QnLJADZ48fkmoavFT1HTgjaJkFlxALiZPjrsfbybD88x6BdL jIXL7jPw25f2VQ9rv4YBDfuoZQGzaD_o2j.sqpvL5K48Gt80JeyXVhnd4HuU LynmiluiuuZ9b X-Rocket-MIMEInfo: 002.001,SSBoYXZlIGEgRGVsbCBJbnNwaXJvbiBONzAxMCBMYXB0b3Agd2l0aCBJbnRlbCBncmFwaGljcy4gV2hlbiB0aGUgZGVsbC1sYXB0b3AgbW9kdWxlIGlzIGxvYWRlZCwKdHdvIGJhY2tsaWdodCBkZXZpY2UgZGV2aWNlcyBhcmUgY3JlYXRlZDsgZGVsbF9iYWNrbGlnaHQsIGFuZCBpbnRlbF9iYWNrbGlnaHQgZnJvbSB0aGUgSW50ZWwKZ3JhcGhpY3MgZHJpdmVyLiBUaGUgZGVsbF9iYWNrbGlnaHQgZGV2aWNlIGlzIG5vbi1mdW5jdGlvbmFsLCBidXQgdGhlIGdyYXBoaWNzIHN1YnN5c3RlbSB1c2VzCml0IGluc3QBMAEBAQE- X-Mailer: YahooMailWebService/0.8.167.602 Message-ID: <1385948627.51494.YahooMailNeo@web160404.mail.bf1.yahoo.com> Date: Sun, 1 Dec 2013 17:43:47 -0800 (PST) From: Alex Davis Reply-To: Alex Davis Subject: [PATCH 1/1] dell_laptop: add disable_backlight module parameter To: "mjg59@srcf.ucam.org" Cc: "linux-kernel@vger.kernel.org" MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I have a Dell Inspiron N7010 Laptop with Intel graphics. When the dell-laptop module is loaded, two backlight device devices are created; dell_backlight, and intel_backlight from the Intel graphics driver. The dell_backlight device is non-functional, but the graphics subsystem uses it instead of the functioning intel_backlight device. The result is that, when running KDE, screen dimming does not work. I've added a module parameter, disable_backlight, which when true will disable the dell_backlight device, and leave only the intel_backlight: with this, screen dimming works. Signed-off-by: Alex Davis --- dell-laptop.c.orig    2013-12-01 19:05:39.693149050 -0500 +++ dell-laptop.c    2013-12-01 17:29:27.613372482 -0500 @@ -35,6 +35,9 @@  /* This structure will be modified by the firmware when we enter   * system management mode, hence the volatiles */   +static bool disable_backlight; +module_param(disable_backlight, bool, 0644); +  struct calling_interface_buffer {      u16 class;      u16 select; @@ -561,6 +564,9 @@ static int __init dell_init(void)        dell_laptop_dir = debugfs_create_dir("dell_laptop", NULL);   +    if (disable_backlight) +        return 0; +  #ifdef CONFIG_ACPI      /* In the event of an ACPI backlight being available, don't       * register the platform controller. I code, therefore I am