From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Giuseppe Bilotta" Subject: Re: [Linux-fbdev-devel] [PATCH] nvidiafb: allow ignoring EDID info Date: Mon, 5 Feb 2007 22:28:36 +0100 Message-ID: References: <20070128160831.fb51347f.akpm@osdl.org> <21d7e9970701281612q56b694edp6efd1a5556dea3fe@mail.gmail.com> <20070128162907.370f5476.akpm@osdl.org> <21d7e9970701281639w57edc2efw4ba620d4c1bdcee7@mail.gmail.com> <20070130203301.GA15067@dreamland.darkstar.lan> <20070204201713.GA12867@dreamland.darkstar.lan> <20070205201824.GA13431@dreamland.darkstar.lan> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20070205201824.GA13431@dreamland.darkstar.lan> Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-Id: Cc: linux-fbdev-devel@lists.sourceforge.net, Andrew Morton , Dave Airlie , linux-kernel@vger.kernel.org On 2/5/07, Luca Tettamanti wrote: > get-edid uses the BIOS, while the other two talk directly over the I2C > bus. > > Try loading i2c-dev (I2C_CHARDEV); With i2cdump[1] you can read the EDID > block, which resides at address 0x50: > > i2cdump N 0x50 (where N is the bus number) > > If you are unshure about bus number try with all the available > /dev/i2c-* devices (you may want to unload HW monitor drivers first, so > you don't poke at random stuff). No luck. i2c-dev and dependencies are loaded """ lsmod | grep i2c reports """ i2c_i801 7404 0 i2c_isa 5152 0 i2c_piix4 8140 0 i2c_algo_pcf 6180 0 i2c_algo_pca 5380 0 i2c_algo_bit 8424 0 i2c_dev 8548 0 i2c_core 19680 7 i2c_i801,i2c_isa,i2c_piix4,i2c_algo_pcf,i2c_algo_pca,i2c_algo_bit,i2c_dev """" There is no such thing as /dev/i2c* UNLESS I load nvidiafb. When I load that, I get three busses (i2c-0, -1, and -2), but i2cdump N 0x50 gives me a nice tableau of X's all around, for all values of N. This is using kernel 2.6.18-3 stock Debian kernel. I'll keep trying with some variations, to see if I can get more sensible information. -- Giuseppe "Oblomov" Bilotta