From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guennadi Liakhovetski Subject: Strange data corruption when read from /sys/class/i2c-adapter/.../eeprom Date: Wed, 3 Dec 2008 13:37:13 +0100 (CET) Message-ID: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org Hi, on an i.MX31-based system I observe a strange effect: cat /sys/class/i2c-adapter/.../eeprom > /tmp/e1 rmmod modprobe cat /sys/class/i2c-adapter/.../eeprom > /tmp/e2 after which the first 0x40 bytes in e2 are zero. The rest is correct - as in e1. To recover I have to rmmod eeprom i2cdetect ... # incluging eeprom addresses modprobe eeprom I would suspect a software bug, but I get this with two alternative adapter drivers (mxc and imx - see my recent post to the list), and on a laptop with 2.6.26 I don't get this. The kernel on i.MX31 is a pretty fresh linux-next. Does this look like a hardware "feature"? Or do we have a regression? Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer