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_PASS autolearn=ham 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 B7575C43142 for ; Wed, 27 Jun 2018 09:51:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A86E22EBF for ; Wed, 27 Jun 2018 09:51:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A86E22EBF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lucaceresoli.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964806AbeF0Ju6 (ORCPT ); Wed, 27 Jun 2018 05:50:58 -0400 Received: from srv-hp10-72.netsons.net ([94.141.22.72]:47723 "EHLO srv-hp10-72.netsons.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934139AbeF0Juz (ORCPT ); Wed, 27 Jun 2018 05:50:55 -0400 Received: from [109.168.11.45] (port=56534 helo=[192.168.101.172]) by srv-hp10.netsons.net with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.91) (envelope-from ) id 1fY76A-004dk1-1P; Wed, 27 Jun 2018 11:50:50 +0200 Subject: Re: [PATCH v4 6/8] media: imx274: add helper function to fill a reg_8 table chunk To: Sakari Ailus Cc: linux-media@vger.kernel.org, Sakari Ailus , Leon Luo , Mauro Carvalho Chehab , linux-kernel@vger.kernel.org References: <1528716939-17015-1-git-send-email-luca@lucaceresoli.net> <1528716939-17015-7-git-send-email-luca@lucaceresoli.net> <20180626122053.gd5jmt2wr35s5oh2@valkosipuli.retiisi.org.uk> <20180627093055.fn6gqpaodzxmhhx3@valkosipuli.retiisi.org.uk> From: Luca Ceresoli Message-ID: <0fc77725-c3bc-871e-c640-11b4607b79c7@lucaceresoli.net> Date: Wed, 27 Jun 2018 11:50:50 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180627093055.fn6gqpaodzxmhhx3@valkosipuli.retiisi.org.uk> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - srv-hp10.netsons.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - lucaceresoli.net X-Get-Message-Sender-Via: srv-hp10.netsons.net: authenticated_id: luca@lucaceresoli.net X-Authenticated-Sender: srv-hp10.netsons.net: luca@lucaceresoli.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sakari, On 27/06/2018 11:30, Sakari Ailus wrote: > On Wed, Jun 27, 2018 at 10:13:12AM +0200, Luca Ceresoli wrote: >> Hi Sakari, >> >> On 26/06/2018 14:20, Sakari Ailus wrote: >>> Hi Luca, >>> >>> On Mon, Jun 11, 2018 at 01:35:37PM +0200, Luca Ceresoli wrote: >>>> Tables of struct reg_8 are used to simplify multi-byte register >>>> assignment. However filling these snippets with values computed at >>>> runtime is currently implemented by very similar functions doing the >>>> needed shift & mask manipulation. >>>> >>>> Replace all those functions with a unique helper function to fill >>>> reg_8 tables in a simple and clean way. >>> >>> What's the purpose of writing these registers as multiple I²C writes, when >>> this can be done as a single write (i.e. the address followed by two or >>> three octets of data)? >> >> Good point. The for loops applying the register values (the lines just >> after those changed by my patch) defuse the regmap bulk write capability. >> >> I guess this could be improved not filling any table, but directly >> calling regmap_bulk_write(), passing the u16 or u32 register value with >> proper endianness. No tables, less code. This would replace the present >> patch with a shorter and more effective one. Is it what you was suggesting? > > Yes, please. Ok, will do. I think this will cut many lines of code, wow! Patch 8 is only marginally related to this change, so it can be reviewed independently except for the few lines in imx274_apply_trimming() where registers are written. -- Luca