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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 523C1C433DF for ; Wed, 27 May 2020 16:09:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 35522208E4 for ; Wed, 27 May 2020 16:09:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729914AbgE0QJ5 (ORCPT ); Wed, 27 May 2020 12:09:57 -0400 Received: from mail.baikalelectronics.com ([87.245.175.226]:37104 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725294AbgE0QJ5 (ORCPT ); Wed, 27 May 2020 12:09:57 -0400 Received: from localhost (unknown [127.0.0.1]) by mail.baikalelectronics.ru (Postfix) with ESMTP id BA1EA8030835; Wed, 27 May 2020 16:09:54 +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 bDkvW9sg6A7Z; Wed, 27 May 2020 19:09:53 +0300 (MSK) Date: Wed, 27 May 2020 19:09:50 +0300 From: Serge Semin To: Andy Shevchenko CC: Serge Semin , Jarkko Nikula , Wolfram Sang , Mika Westerberg , Alexey Malahov , Thomas Bogendoerfer , Rob Herring , , , , Subject: Re: [PATCH v5 08/11] i2c: designware: Convert driver to using regmap API Message-ID: <20200527160950.p3brpiup3pihlzi6@mobilestation> References: <20200527153046.6172-1-Sergey.Semin@baikalelectronics.ru> <20200527153046.6172-9-Sergey.Semin@baikalelectronics.ru> <20200527160337.GL1634618@smile.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20200527160337.GL1634618@smile.fi.intel.com> X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 27, 2020 at 07:03:37PM +0300, Andy Shevchenko wrote: > On Wed, May 27, 2020 at 06:30:43PM +0300, Serge Semin wrote: > > Seeing the DW I2C driver is using flags-based accessors with two > > conditional clauses it would be better to replace them with the regmap > > API IO methods and to initialize the regmap object with read/write > > callbacks specific to the controller registers map implementation. This > > will be also handy for the drivers with non-standard registers mapping > > (like an embedded into the Baikal-T1 System Controller DW I2C block, which > > glue-driver is a part of this series). > > > > As before the driver tries to detect the mapping setup at probe stage and > > creates a regmap object accordingly, which will be used by the rest of the > > code to correctly access the controller registers. In two places it was > > appropriate to convert the hand-written read-modify-write and > > read-poll-loop design patterns to the corresponding regmap API > > ready-to-use methods. > > > > Note the regmap IO methods return value is checked only at the probe > > stage. The rest of the code won't do this because basically we have > > MMIO-based regmap so non of the read/write methods can fail (this also > > won't be needed for the Baikal-T1-specific I2C controller). > > ... > > > + struct regmap_config map_cfg = { > > + .reg_bits = 32, > > + .val_bits = 32, > > + .reg_stride = 4, > > + .disable_locking = true, > > + .reg_read = dw_reg_read, > > + .reg_write = dw_reg_write, > > > + .max_register = DW_IC_COMP_TYPE > > Perhaps leave comma here as well. If v6 is required, it'll be fixed there. -Sergey > > > + }; > > ... > > > + /* > > + * Note we'll check the return value of the regmap IO accessors only > > + * at the probe stage. The rest of the code won't do this because > > + * basically we have MMIO-based regmap so non of the read/write methods > > + * can fail. > > + */ > > + dev->map = devm_regmap_init(dev->dev, NULL, dev, &map_cfg); > > + if (IS_ERR(dev->map)) { > > + dev_err(dev->dev, "Failed to init the registers map\n"); > > > + return PTR_ERR(dev->map); > > + } > > + > > return 0; > > return PTR_ERR_OR_ZERO(dev->map); > > -- > With Best Regards, > Andy Shevchenko > >