From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michel Alexandre Salim Subject: Need help debugging Sony Vaio VPCY2 backlight control problem Date: Fri, 01 Jul 2011 21:34:45 +0200 Message-ID: <4E0E2155.4070508@fedoraproject.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-acpi-owner@vger.kernel.org To: linux-acpi@vger.kernel.org, platform-driver-x86 Cc: Mattia Dongili , Marco Chiappero List-Id: platform-driver-x86.vger.kernel.org Dear all, (cc:ing Mattia and Marco since they seem to be actively working on sony-laptop.ko) I have a Sony Vaio VPCY2 with a backlight control problem -- both with acpi_backlight=video and acpi_backlight=vendor. With the former, setting the backlight (with Fn-F5/6) gave the appearance, as far as /sys/class/backlight/acpi_video0/{actual_,}brightness is concerned, that the change took place, however, the screen brightness remained unchanged. Even setpci-ing the hardware register does not make a difference. Kernel bug report here: https://bugzilla.kernel.org/show_bug.cgi?id=38342 Fedora bug report: https://bugzilla.redhat.com/show_bug.cgi?id=689962 Is the Vaio Y's backlight supposed to be controlled by sony-laptop instead of by video.ko? Right now with sony-laptop, actual_brightness always reads -1 no matter what value is written to brightness. If there's any information not currently attached to those bug reports that is needed, please let me know. Thanks in advance, -- Michel Alexandre Salim GPG key ID: 78884778 () ascii ribbon campaign - against html e-mail /\ www.asciiribbon.org - against proprietary attachments