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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E9609EE4996 for ; Mon, 21 Aug 2023 10:46:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232758AbjHUKqT (ORCPT ); Mon, 21 Aug 2023 06:46:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234857AbjHUKqS (ORCPT ); Mon, 21 Aug 2023 06:46:18 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD230E1 for ; Mon, 21 Aug 2023 03:46:16 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4A4866306D for ; Mon, 21 Aug 2023 10:46:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC2D9C433CC; Mon, 21 Aug 2023 10:46:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1692614775; bh=65wh16l+ICzU8nHCRWK8MMfP6V+OTIGsyMZhuVYGVuI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Oi+KrBI36kZkq3WH5E8DLjWMjC8Q+6/iDWypFCocDpFQT0k0C/KkaeKqjT07pHvKa xwVkDJRKWwLqF+5rLOWqT/5pYDXU9Us/4cMB/PYAh3iLy1Kdt5qFoWJCGOmerSmSud OZWiQiRYlY89bqPM7NVc/AEAbY6r7KYf/7pUU3V93GnLDQ2f/nily84OfjxY633PIZ MIr2JNiaHUzOHK7yLYLw0ML1ZXufnJe4kXIpj6PRH3X+lTxF58w8Pv07XRtRR210Kb kTiWBXtXA7cblB8TDeBqwsEtvctv1d6ZZly2cUQimhQzFhPxNYndgJqIywPwsvyTXQ WGfgiMKkrYUBw== Date: Mon, 21 Aug 2023 12:46:11 +0200 From: Marek =?UTF-8?B?QmVow7pu?= To: Lee Jones Cc: Pavel Machek , linux-leds@vger.kernel.org Subject: Re: [PATCH v3 6/6] leds: turris-omnia: add support for enabling/disabling HW gamma correction Message-ID: <20230821124611.56bc70c3@dellmb> In-Reply-To: <20230818103003.GS986605@google.com> References: <20230802160748.11208-1-kabel@kernel.org> <20230802160748.11208-7-kabel@kernel.org> <20230818103003.GS986605@google.com> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org On Fri, 18 Aug 2023 11:30:03 +0100 Lee Jones wrote: > > -static int omnia_cmd_read(const struct i2c_client *client, u8 cmd) > > +static int omnia_cmd_read_raw(struct i2c_adapter *adapter, u8 addr, u8 cmd, > > + void *reply, size_t len) > > { > > struct i2c_msg msgs[2]; > > - u8 reply; > > int ret; > > > > - msgs[0].addr = client->addr; > > + msgs[0].addr = addr; > > msgs[0].flags = 0; > > msgs[0].len = 1; > > msgs[0].buf = &cmd; > > - msgs[1].addr = client->addr; > > + msgs[1].addr = addr; > > msgs[1].flags = I2C_M_RD; > > - msgs[1].len = 1; > > - msgs[1].buf = &reply; > > + msgs[1].len = len; > > + msgs[1].buf = reply; > > > > - ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); > > + ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs)); > > if (likely(ret == ARRAY_SIZE(msgs))) > > - return reply; > > + return 0; > > Why not return ret and use that throughout? > > > else if (ret < 0) > > return ret; > > else > > return -EIO; > > } > As I explained to your similar question in your reply to patch 2/6 https://lore.kernel.org/linux-leds/20230821120136.130cc916@dellmb/T/#me5782c9896bc3d994cb36e8b5485d6368cd92da0 the reason I normalize to zero is because of the intended semantics of these functions: return 0 on success, -errno on error. If instead in omnia_cmd_read() and omnia_cmd_write() I simply return the return value of the underlying functions, which are i2c_transfer() for omnia_cmd_read() i2c_master_send() for omnia_cmd_write() the semantics would be inconsistent, because: i2c_transfer() returns the number of successful I2C transfers, i2c_manster_send() returns the number of written bytes over I2C. Nonetheless, if you insist on this change, I will do it. Reluctantly and with a silent protest, but I will not argue further, since I want this functionality in upstream more than to argue over nitpicks :-) Marek