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 0AE6DC61DA4 for ; Thu, 9 Mar 2023 09:40:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=gi0atjIh5gqLJzg+nV+aruQRZl+CO38uNzwZWXC6iGU=; b=1f/7IGMxO1Cub1 bWrBYGh8+FxjGwDqreUOtOrI+eOkir3ObQPlc21Ox5xrtBdV2ADgPgAvJezzkHbcci63n6/yOqP1K oClZfbCxmgZaZCAWhxWMcS/WaRQr6HEaPxLQDEMGdO0pXVoEyVCJ+ska/aDtht1kkgvLltjZfdq3p fN5GKvagyk3wdIrXIga3SVyc7uPQdb3G56utmMbAnxXqFjuV8pmmnwGuZXKXpK1nWhobkyNTZOSsC +LBXfBZyZdEjWD1iTCJFDhZ5Z8cbU8f7Ifk6leQsBRNTTMF4Ajs/pr8/Vc9Yc6ZDl9EqdWzPvEj6k 490O/Wy16x0sLAXVRFdg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1paCl8-008rBH-3x; Thu, 09 Mar 2023 09:40:26 +0000 Received: from 0001.3ffe.de ([2a01:4f8:c0c:9d57::1] helo=mail.3ffe.de) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1paCl1-008r75-E1; Thu, 09 Mar 2023 09:40:20 +0000 Received: from mwalle01.kontron.local. (unknown [213.135.10.150]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.3ffe.de (Postfix) with ESMTPSA id 0EF2A127D; Thu, 9 Mar 2023 10:40:16 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2022082101; t=1678354816; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=j6A1cqIav5oN+sJ0Pm8CyKz7tSgwht+condPuImcVwY=; b=zsMPy9kNOSpYIQk2v92UlAChhQ1RPWvR19mptAEqIVjK7y7MtNDhCwb2WjCLD1XqQrz1Lw q8s4RCfCX8HShn15fWBvySjzhsBHUFHE1ZVKHu5VkB4RcwxibgapaU57G1lZ9MaCbGS+ZB d8zZihUMbqMqbCgfK1NPj8qFc6HdOzqsvmbsDviuS3ZwcHJ6DMQw2zRg/+2Ht3+IwL13B9 3XbUFM/uL/TIFiDCwAouAEb4qEnSGJF/f7NhSKUHWODVLEtFviq2WFQVuobulTjGODAOt4 qJx7Hf6BNV7PeSGwCgjwgSvM/epAZE1St3F3Qp7iV4+07CGebjwrTQ4MPMgtqQ== From: Michael Walle To: zajec5@gmail.com Cc: a.zummo@towertech.it, agross@kernel.org, alexandre.belloni@bootlin.com, alexandre.torgue@foss.st.com, alyssa@rosenzweig.io, andersson@kernel.org, angelogioacchino.delregno@collabora.com, asahi@lists.linux.dev, baolin.wang@linux.alibaba.com, claudiu.beznea@microchip.com, festevam@gmail.com, hayashi.kunihiko@socionext.com, heiko@sntech.de, jbrunet@baylibre.com, jernej.skrabec@gmail.com, kernel@pengutronix.de, khilman@baylibre.com, konrad.dybcio@linaro.org, linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-imx@nxp.com, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-mtd@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-rtc@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-sunxi@lists.linux.dev, marcan@marcan.st, martin.blumenstingl@googlemail.com, matthias.bgg@gmail.com, mcoquelin.stm32@gmail.com, mhiramat@kernel.org, michal.simek@xilinx.com, miquel.raynal@bootlin.com, neil.armstrong@linaro.org, orsonzhai@gmail.com, rafal@milecki.pl, richard@nod.at, s.hauer@pengutronix.de, samuel@sholland.org, shawnguo@kernel.org, srinivas.kandagatla@linaro.org, sven@svenpeter.dev, vigneshr@ti.com, vincent.sunplus@gmail.com, wens@csie.org, zbr@ioremap.net, zhang.lyra@gmail.com, Michael Walle Subject: Re: [PATCH V2] nvmem: add explicit config option to read OF fixed cells Date: Thu, 9 Mar 2023 10:40:10 +0100 Message-Id: <20230309094010.1051573-1-michael@walle.cc> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230224072903.20945-1-zajec5@gmail.com> References: <20230224072903.20945-1-zajec5@gmail.com> MIME-Version: 1.0 X-Spam: Yes X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230309_014019_651227_B407760E X-CRM114-Status: GOOD ( 15.72 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org [as this mentions nvmem layouts it would have been nice to include me] > NVMEM subsystem looks for fixed NVMEM cells (specified in DT) by > default. This behaviour made sense in early days before adding support > for dynamic cells. Why is that? It still makes sense, doesn't it? > With every new supported NVMEM device with dynamic cells current > behaviour becomes non-optimal. It results in unneeded iterating over DT > nodes and may result in false discovery of cells (depending on used DT > properties). What false discoveries? > This behaviour has actually caused a problem already with the MTD > subsystem. MTD subpartitions were incorrectly treated as NVMEM cells. But this is solved, correct? > Also with upcoming support for NVMEM layouts no new binding or driver > should support fixed cells defined in device node. How would you support older device trees with newer kernels or the other way around? I'm not sure I get your motivation to drop handling the fixed cells. > Solve this by modifying drivers for bindings that support specifying > fixed NVMEM cells in DT. Make them explicitly tell NVMEM subsystem to > read cells from DT. How can a driver know when there are fixed cells and when not? IOW. only new ones can be affected. If you want to get rid of the schema for *new* drivers then what about having a new child node, something like "nvmem-fixed-cells", similar to "nvmem-layout". And then you'd tell the new drivers to use the new-style dt binding. But there are no new drivers yet. So I'm still not sure I get your motivation. -michael _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip