From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Nikula Subject: Re: [PATCH v2] i2c: i801: Fix I2C Block Read on 8-Series/C220 and later Date: Mon, 17 Oct 2016 15:38:06 +0300 Message-ID: <63a30963-9ac4-15df-5130-bb72e74d7f51@linux.intel.com> References: <20161011131327.0eabd227@endymion> <20161011202045.43787f2e@endymion> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mga05.intel.com ([192.55.52.43]:64722 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934840AbcJQMiJ (ORCPT ); Mon, 17 Oct 2016 08:38:09 -0400 In-Reply-To: <20161011202045.43787f2e@endymion> Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Jean Delvare Cc: Linux I2C , Mika Westerberg , Wolfram Sang Hi On 10/11/2016 09:20 PM, Jean Delvare wrote: >>> Jarkko, still no information about this from your Windows or hardware >>> folks? >> >> No update, in fact some of the contacts have left the company :-( > > What do we do then? Without this patch, I2C Block Read doesn't work at > all on recent chipsets. I don't think it can be worse with the patch. > And it works fine on the few machines I tested on. So I would like this > patch to go upstream. > > My coverage is limited though. Did anyone at Intel test this patch on > other (recent) systems? > Sorry the delay. I have only handful of machine that have on-board EEPROM connected to SMBUS in our lab and they are relatively new so only limited testing from my side. In fact those had the SPD Write Disable set so attempt to use kernel's at24 driver didn't register the EEPROM at all without your patch since one-byte test read in drivers/misc/eeprom/at24.c: at24_probe() failed. echo "24c02 0x56" >/sys/bus/i2c/devices/i2c-0/new_device With your patch at24 probes and I can dump the 0xff content (I guess it's unprogrammed) with the hexdump: hexdump -C /sys/bus/i2c/devices/i2c-0/0-0056/eeprom I think we are better to have this patch as we know it makes things better. I'll add my tested-by to your patch with one comment. -- Jarkko