From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 13827C433DF for ; Wed, 27 May 2020 11:20:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E8465207E8 for ; Wed, 27 May 2020 11:20:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388207AbgE0LUG (ORCPT ); Wed, 27 May 2020 07:20:06 -0400 Received: from mail.baikalelectronics.com ([87.245.175.226]:34554 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388146AbgE0LUF (ORCPT ); Wed, 27 May 2020 07:20:05 -0400 Received: from localhost (unknown [127.0.0.1]) by mail.baikalelectronics.ru (Postfix) with ESMTP id 90624803080A; Wed, 27 May 2020 11:20:02 +0000 (UTC) X-Virus-Scanned: amavisd-new at baikalelectronics.ru Received: from mail.baikalelectronics.ru ([127.0.0.1]) by localhost (mail.baikalelectronics.ru [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9Bltaobyr5kB; Wed, 27 May 2020 14:20:01 +0300 (MSK) Date: Wed, 27 May 2020 14:20:01 +0300 From: Serge Semin To: Rob Herring CC: Serge Semin , Jarkko Nikula , Wolfram Sang , Frank Rowand , Alexey Malahov , Thomas Bogendoerfer , Mika Westerberg , , , , Subject: Re: [PATCH v3 01/12] scripts/dtc: check: Add 10bit/slave i2c reg flags support Message-ID: <20200527112001.pxnzd4ofxsps7x57@mobilestation> References: <20200526215528.16417-1-Sergey.Semin@baikalelectronics.ru> <20200526215528.16417-2-Sergey.Semin@baikalelectronics.ru> <20200527011704.GA808104@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20200527011704.GA808104@bogus> X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org On Tue, May 26, 2020 at 07:17:04PM -0600, Rob Herring wrote: > On Wed, May 27, 2020 at 12:55:17AM +0300, Serge Semin wrote: > > Recently the I2C-controllers slave interface support was added to the > > kernel I2C subsystem. In this case Linux can be used as, for example, > > a I2C EEPROM machine. See [1] for details. Other than instantiating > > the EEPROM-slave device from user-space there is a way to declare the > > device in dts. In this case firstly the I2C bus controller must support > > the slave interface. Secondly I2C-slave sub-node of that controller > > must have "reg"-property with flag I2C_OWN_SLAVE_ADDRESS set (flag is > > declared in [2]). That flag is declared as (1 << 30), which when set > > makes dtc unhappy about too big address set for a I2C-slave: > > > > Warning (i2c_bus_reg): /example-2/i2c@1120000/eeprom@64: I2C bus unit address format error, expected "40000064" > > Warning (i2c_bus_reg): /example-2/i2c@1120000/eeprom@64:reg: I2C address must be less than 10-bits, got "0x40000064" > > > > Similar problem would have happened if we had set the 10-bit address > > flag I2C_TEN_BIT_ADDRESS in the "reg"-property. > > > > In order to fix the problem we suggest to alter the I2C-bus reg-check > > algorithm, so one would be aware of the upper bits set. Normally if no > > flag specified, the 7-bit address is expected in the "reg"-property. > > If I2C_TEN_BIT_ADDRESS is set, then the 10-bit address check will be > > performed. The I2C_OWN_SLAVE_ADDRESS flag will be just ignored. > > > > [1] Documentation/i2c/slave-interface.rst > > [2] include/dt-bindings/i2c/i2c.h > > > > Signed-off-by: Serge Semin > > Cc: Alexey Malahov > > Cc: Thomas Bogendoerfer > > Cc: Mika Westerberg > > Cc: linux-mips@vger.kernel.org > > Cc: linux-i2c@vger.kernel.org > > --- > > scripts/dtc/checks.c | 13 +++++++++---- > > 1 file changed, 9 insertions(+), 4 deletions(-) > > I've lost track of who all I've said this to already for this issue, but > patches to dtc should be against upstream and a version of this has been > sent there already. But it seems they've lost interest in addressing the > review comments. So feel free to send another one. The same comment > applies here. There is another patch in this series: [PATCH v3 04/12] dt-bindings: i2c: dw: Add Baikal-T1 SoC I2C controller which is also waiting for your review. I've updated it as you requested. Could you take a look at that too? -Sergey > > Rob