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=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 29EA9C4338F for ; Wed, 25 Aug 2021 14:34:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0F590610C7 for ; Wed, 25 Aug 2021 14:34:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241756AbhHYOfU (ORCPT ); Wed, 25 Aug 2021 10:35:20 -0400 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:7362 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S232168AbhHYOfT (ORCPT ); Wed, 25 Aug 2021 10:35:19 -0400 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.1.2/8.16.0.43) with SMTP id 17PDhOum003655; Wed, 25 Aug 2021 16:34:13 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=from : subject : to : cc : message-id : date : mime-version : content-type : content-transfer-encoding; s=selector1; bh=uB5VgDvAvQ72i1SM94ZVMnpWG1uPhE/nxCUf1gUKsDM=; b=J8/nsnlyrDt5jpFg+8ufKUpDe6dVqgJmzghbCCt+7/M/+I3kVGJCgbzgdP3TQZCjIOTe iWbxcWomfrrB10/SNyFZTN1CM6gGvvVUDK5QtgRueMmhZnJIedm+5AVnYPd+Nlv1kono MUbyH1DR3gCN6eP+mU/cbblmM8l5F+Oxg1IUTlE7N8wi+DTA6ewIA+82kIMzO4+KKv76 9dxXrNsvU+WNHO0uqnXDhqyRYxo6MeCE+1ObFqDjvqAleK0tWd86Y5U7APjKMOvX3Xhn C3f7JdvJgVPaALaIESNwEYpJClgEYYakEtGyDlmOAtlDSPv7nhgLs/3HfZnrhOe61voI Hg== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 3ana52vvwe-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 25 Aug 2021 16:34:13 +0200 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 00AD910002A; Wed, 25 Aug 2021 16:34:11 +0200 (CEST) Received: from Webmail-eu.st.com (sfhdag2node3.st.com [10.75.127.6]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id C47FC25F3F3; Wed, 25 Aug 2021 16:34:11 +0200 (CEST) Received: from lmecxl0504.lme.st.com (10.75.127.48) by SFHDAG2NODE3.st.com (10.75.127.6) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 25 Aug 2021 16:34:10 +0200 From: Yann Gautier Subject: Question about MMC_PM_KEEP_POWER in MMCI driver To: Ulf Hansson , "linux-mmc@vger.kernel.org" CC: Linus Walleij , Russell King , Rob Herring , "linux-arm-kernel@lists.infradead.org" , , "linux-stm32@st-md-mailman.stormreply.com" , Message-ID: Date: Wed, 25 Aug 2021 16:34:10 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.75.127.48] X-ClientProxiedBy: SFHDAG1NODE2.st.com (10.75.127.2) To SFHDAG2NODE3.st.com (10.75.127.6) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.182.1,Aquarius:18.0.790,Hydra:6.0.391,FMLib:17.0.607.475 definitions=2021-08-25_06,2021-08-25_02,2020-04-07_01 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi, In drivers/mmc/host/mmci.c, MMC_PM_KEEP_POWER is unconditionally enabled. This prevents correct low-power sequence on STM32MP157C-DK2 board which embeds a Wifi chip brcm,bcm4329-fmac (this wifi part has not yet been sent upstream). This MMC_PM_KEEP_POWER can be taken from DT with the property keep-power-in-suspend. This is what is done for other MMC drivers. I wonder what should be the best solution for this. 1) Remove MMC_PM_KEEP_POWER from the driver, and modify all SoC device tree files embedding a arm,pl18x with adding keep-power-in-suspend; property (except stm32mp151.dtsi file). This can be easy to do (~10 files to modify). But that could be more board dependent, if an SDIO chip is plugged on this MMC IP. And the name keep-power-in-suspend can be misleading as it only applies to SDIO. 2) Remove MMC_PM_KEEP_POWER from the driver, and modify board DT files with the property. This could be a difficult task to find all those boards. And this should be applied only for SDIO configs. 3) Just modify the driver to apply this capability for all MMCI chips but STM32. This could be done in the dedicated file, in sdmmc_variant_init() function. But some boards based on STM32MP15 chip might want to keep this capability. All advice is welcome. Thanks, Yann