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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B7242C36010 for ; Fri, 11 Apr 2025 14:26:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=NOvfAcC4nSHwovxfMmc7lJ6Xohxm7kKLQxmp9yLUv58=; b=kFWUNJ+pwyAdYXPo3RlF8rRRLu resRV9j5fhTDk/8a/Jk8pBNbAay/SGDzUV3uWeSONsHUomUri7tzIrJ3SMO3qt7R2dUYDhYbMqlHI 1djhrfKSNML39wQzJAtelImKrFzFgWgEC/4ZF82cYMH1tjl33UMnOGh+/xx/2fuSxv55Fkjmy7/S2 C4Fx7gpAtaVZMTbfNrA1ROElfO71Lwpj433Z1vSVvjsQDpWCjdoodcSz3NuMDUiloYpaKHze32ckm p/UoUVmHQ6GNZ0/ujkeZrvhLoqwwfLwsIv0GYgxZWT1wvFRO4MW1+wPQ9gjUZvl5zcI3S6Y9jOARb QCzhX01Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1u3FKd-0000000E5Gj-2wb1; Fri, 11 Apr 2025 14:26:11 +0000 Received: from mail-ed1-x52e.google.com ([2a00:1450:4864:20::52e]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1u3F21-0000000E1tk-2kWh for linux-arm-kernel@lists.infradead.org; Fri, 11 Apr 2025 14:06:58 +0000 Received: by mail-ed1-x52e.google.com with SMTP id 4fb4d7f45d1cf-5e6167d0536so3668842a12.1 for ; Fri, 11 Apr 2025 07:06:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1744380415; x=1744985215; darn=lists.infradead.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=NOvfAcC4nSHwovxfMmc7lJ6Xohxm7kKLQxmp9yLUv58=; b=dkSsc35oGn5Dh/e4IRdho5euPRfdkhuirqu7D9GqTbPiQ4gW6ziwFVdWqMt3VjrC5b gIGWFgWVD0591xBHAcYcRS5kN3xPOmXTak51tFFfzIgp80KbIozGslCu1B1rV0arPUdW aKEWoubIgemJbsyXPgoGQovt4IcG3W8LlLeUo1TXOAN1KA/FhxFPKacs6kQxhweBe/Qi wl0cSiZL60klYnFJ6pYXIxJtR2KKjFAosBWvAq4k5CcwMztYNJFhY8A8qifxOIVPyNZY 4Zjpj0Djr8Krc542tmr+0j8OMaPJOcX2Y+Gd0e+82xdcDkkNbdHNdJQTDeWPAKKZrSj6 agqg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1744380415; x=1744985215; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=NOvfAcC4nSHwovxfMmc7lJ6Xohxm7kKLQxmp9yLUv58=; b=T/jRPf9sZqaYEEjcT8Q3A/jNO/o0Elk7WT99tUNiT+L+zlGoxVlsu/5Q3H+/MjvLpv bL7WjFu2EA7LpkNF5PS0Sfhs1joH0EzSRlKT8jHK+SvSsBogV/apk3DTuMt+blYDudul MZonT+fmIj5hbeWIaUK6Nyszge5BeFe1OEIzf47NuQvZ6a2mWkkBke5u/UdruL/Zfj29 /fKhp7DQg1tYME2dZ3XM+Wo1OMH91FVSPpAOEf8jRiYQflH09n2y2hkNbjgJbbN0Pxla P7ueihlNUMxO0CoMozIQ2MpYkEOxS5yvAgUmM8X9VLm9P90GZtQh/OPLZ6E5plHSHD1s bcKg== X-Forwarded-Encrypted: i=1; AJvYcCUreZWFowcO9DgP1VZ1CoPtLHT2OEHTqJ8V7wpUc3rb+eCEkHynVJNvNwCVSfxGUG1fBWNrrNfPUUA0vHN2vWl2@lists.infradead.org X-Gm-Message-State: AOJu0Yycjvq2IVHEjMQrqO72PutdDBbP19VhMCEjwWLeCz/DV2NsXXPb nVpBzzOO5CnxWl9LjNqGaOZ5ORqhxXz86ss/kgkk8o4uITHMMxOb X-Gm-Gg: ASbGncvc5UT6fym2MH9/aKRNx7vOchmKPgsc2UF8m1QKk7k5kyEZSGhpY7vD54wW64N Gq6hDrL9GziTGIuGszOzecJ7MEA23hWo2tIecKI1k1rv+ypaa3wBwQ6g/LXWr4WIIDH5r4W6EwH BQQJTL/gujpk356u3XZ8Sbs6UUYOuGTVp4OKA03RfB0n9tuyjtxD0vI2PX3EfDy+qlhkAFw1Kvq RxMx5Nnm8cuOnOfx15ehXXBipP3+QPG7YTIXUwKAjEcpwsiF3WzFnO8X8BLZ5ZhWGhHCAGpU3SL nJIvrxpHYEG3nemxi/CEj7VE6uPzkE6nF7/P4537atJXJNPZkppRdiFE1DXo/715FnCp8JFr2r8 VeVnLIGS+9g0mI5gHtA== X-Google-Smtp-Source: AGHT+IE1yOeDj9VvnJ4cJ143MdQvjsuVm7s+alTj6cIAtIkzd0ZDaU4JF1U6ysR5rjPt1629SVONMQ== X-Received: by 2002:a05:6402:1ecc:b0:5ec:9352:7b20 with SMTP id 4fb4d7f45d1cf-5f36ee45999mr2263715a12.0.1744380415128; Fri, 11 Apr 2025 07:06:55 -0700 (PDT) Received: from ?IPV6:2001:b07:aac:705d:8db5:5583:1b6d:7bba? ([2001:b07:aac:705d:8db5:5583:1b6d:7bba]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5f36ee54fa9sm1005741a12.1.2025.04.11.07.06.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 11 Apr 2025 07:06:54 -0700 (PDT) Message-ID: <2af51b9c-cde6-4347-b062-daa87bddd8ff@gmail.com> Date: Fri, 11 Apr 2025 16:06:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1] i2c: lpi2c: implement master_xfer_atomic callback To: Carlos Song Cc: Pengutronix Kernel Team , Fabio Estevam , Emanuele Ghidoli , "linux-i2c@vger.kernel.org" , "imx@lists.linux.dev" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Francesco Dolcini , Francesco Dolcini , Aisheng Dong , Andi Shyti , Shawn Guo , Sascha Hauer References: <20250319145114.50771-1-francesco@dolcini.it> <20250411114738.GA43965@francesco-nb> Content-Language: en-US From: Emanuele Ghidoli In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250411_070657_698076_83179E7E X-CRM114-Status: GOOD ( 12.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 11/04/2025 13:55, Carlos Song wrote: >> On Wed, Mar 19, 2025 at 03:51:14PM +0100, Francesco Dolcini wrote: >>> From: Emanuele Ghidoli >>> >>> Rework the read and write code paths in the driver to support >>> operation in atomic contexts. To achieve this, the driver must not >>> rely on IRQs or perform any scheduling, e.g., via a sleep or schedule >>> routine. Even jiffies do not advance in atomic contexts, so timeouts >>> based on them are substituted with delays. >>> >>> Implement atomic, sleep-free, and IRQ-less operation. This increases >>> complexity but is necessary for atomic I2C transfers required by some >>> hardware configurations, e.g., to trigger reboots on an external PMIC chip. >>> >>> Signed-off-by: Emanuele Ghidoli >>> Signed-off-by: Francesco Dolcini >> >> Any comment on this? > Looks good. Thank you for your work! > Do you test it at some board? How can we test simply? We tested it also by using the xfer_atomic for "normal" transfers (.master_xfer = lpi2c_imx_xfer_atomic). The driver is used to drive multiple buses with different devices. Emanuele