From mboxrd@z Thu Jan 1 00:00:00 1970 Mime-Version: 1.0 Message-Id: In-Reply-To: <20011118174724.HJSA24249.tomts11-srv.bellnexxia.net@there> References: <20011118174724.HJSA24249.tomts11-srv.bellnexxia.net@there> Date: Sun, 18 Nov 2001 13:28:57 -0800 To: "Kevin B. Hendricks" , linuxppc-dev@lists.linuxppc.org From: "Timothy A. Seufert" Subject: Re: How to control Brightness for Flat Panels? Content-Type: text/plain; charset="us-ascii" ; format="flowed" Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: At 12:50 PM -0500 11/18/01, Kevin B. Hendricks wrote: >Hi, > >How do we go about controlling "brightness" for Flat Panels? Is this >functionality in the radeonfb.c or the XFree86 code? > >The new Apple FlatPanels has no manual brightness knob or control so it >must be done in software. > >Ideas anyone? For Apple's monitors this might actually happen through USB. ADC has it, and it would be a handy data path to use for such commands. The fact that MacOS 9 has a "USBAppleMonitorModule" extension and MacOS X has "AppleUSBDisplays.kext" is suggestive. If it is in fact USB, you could probably write a userspace program (using libusb) without touching XFree86 or radeonfb at all. The tough part would be deciphering the protocol. (Pretty easy if you have a USB protocol analyzer to watch what MacOS does.) -- Tim Seufert ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/