From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean Delvare Subject: i2c-i801 partially broken on Lynx Point PCH? Date: Wed, 11 May 2016 09:34:52 +0200 Message-ID: <20160511093452.5bc2614c@endymion> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from mx2.suse.de ([195.135.220.15]:59125 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751271AbcEKHe4 (ORCPT ); Wed, 11 May 2016 03:34:56 -0400 Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Seth Heasley Cc: Linux I2C , Mika Westerberg , Jarkko Nikula Hi Seth, In commit 062737fb6d90 you added support for the Intel Lynx Point PCH to the i2c-i801 driver. I happen to have a machine with this chipset since a few weeks, and found that the i2c-i801 driver doesn't work properly on it. Specifically, the eeprom driver return 0xff for all EEPROM bytes. The at24 driver fails too, with a timeout. After some testing using i2cdetect, i2cdump and i2cget, I found that some I2C transactions work (SMBUS_QUICK, SMBUS_READ_BYTE, SMBUS_READ_BYTE_DATA, SMBUS_READ_WORD_DATA, SMBUS_READ_BLOCK_DATA), however others do not (SMBUS_WRITE_BYTE, SMBUS_READ_I2C_BLOCK.) I can't easily test other transaction types as all I have on the SMBus are SPD EEPROMs on my memory modules. Did you test the i2c-i801 driver on an actual Lynx Point PCH chipset? Or did you only add the PCI ID of the device, assuming it would work? -- Jean Delvare SUSE L3 Support