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 E110BC433EF for ; Tue, 1 Feb 2022 03:18:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232924AbiBADSi (ORCPT ); Mon, 31 Jan 2022 22:18:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43942 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232779AbiBADSg (ORCPT ); Mon, 31 Jan 2022 22:18:36 -0500 Received: from mail-pf1-x433.google.com (mail-pf1-x433.google.com [IPv6:2607:f8b0:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE611C06173D for ; Mon, 31 Jan 2022 19:18:36 -0800 (PST) Received: by mail-pf1-x433.google.com with SMTP id e28so14634421pfj.5 for ; Mon, 31 Jan 2022 19:18:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:in-reply-to:references:date:message-id :mime-version; bh=7ym4guToR5s6XJh+Gyaw0SuEv+LKx7FC/++SseskIfM=; b=E++ef+Q5iBCT3v/I5Xsw8Z42hgWOa0/CD59TDIXkDMY0W82NoIdVaA2wlQHAOqNgPW HVlfHK7n3vd7hCpdQvMsLK+QRFDHf+nMqZyVlPoR39FJ9/sq7mok7WbE7LsSq4UA96gB y4d/Dw5IEj6UGsD60pfH56R5yEmEtlkHe/oa+JG1q70MRkM214E+Q2ZVc2fM23xLE0Rt nhKk1G3dW79j8cHJpcnHjsPzWteJo7l2qH3qiSzZnoOBl9BjPaFQed0VBv+B3JHC4XOO dXEN0f2BkRCdaUQwNKxUlXgbqy2rWF2PXQUOdD42KKaisUfUC2EeMsCfLbv2tZHgtZuT 824A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=7ym4guToR5s6XJh+Gyaw0SuEv+LKx7FC/++SseskIfM=; b=jefIi8nvlsB1yPoZNtngkBvDV1RUeQQ3WTcMnYWG3+mtu+dC/x4rvHlDHiBLm5LNfy G2Du+Xj7JE62UHjeBs734C+Is19kt99KQzIxhoYzua7nWyao8DDlo8bzVaDy1m3LyYtC TKQuu7PTSzSwpK9rWxE/1Cz266SsfbB7JbnCNRzBNxCTCvALoQ+dT3XyRc+Ft5wnyCwg D01JwB0M/RDUM8IKx6uXCHZkk+bV3KvDGYhr21Pj8vJy0jEb3lcSGdZWAKALL+Ivubih 4nmnWpXOKUiUgbZJMVCkGvWuuEPVCcB1GESFogGON4PXaZmjZORdl6C8WbYeweWNUuWv H3lw== X-Gm-Message-State: AOAM530lwWMJT2EaLuX9ZWQtcE7en+/kIiYfduVPsTxPKn0uh9F39cka QIJLfhWDeTAPRt0Alji0+GNDNw== X-Google-Smtp-Source: ABdhPJz49oSgsvYX6rVkuwCkpBFyCD/1vuYWgent4FpvFLEF81sRjkDpqWZmQXP+xsW7pCXULByM5A== X-Received: by 2002:a63:2c83:: with SMTP id s125mr15529210pgs.265.1643685516138; Mon, 31 Jan 2022 19:18:36 -0800 (PST) Received: from localhost (c-71-197-186-152.hsd1.wa.comcast.net. [71.197.186.152]) by smtp.gmail.com with ESMTPSA id c8sm13261985pfv.57.2022.01.31.19.18.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 31 Jan 2022 19:18:35 -0800 (PST) From: Kevin Hilman To: Saravana Kannan , Russell King , Neil Armstrong , Geert Uytterhoeven , Magnus Damm , Tony Lindgren , Catalin Marinas , Will Deacon , Damien Le Moal , Greg Kroah-Hartman , Saravana Kannan Cc: Ulf Hansson , Rob Herring , kernel-team@android.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-oxnas@groups.io, linux-renesas-soc@vger.kernel.org, linux-omap@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v4 1/2] drivers: bus: simple-pm-bus: Add support for probing simple bus only devices In-Reply-To: <20210929000735.585237-2-saravanak@google.com> References: <20210929000735.585237-1-saravanak@google.com> <20210929000735.585237-2-saravanak@google.com> Date: Mon, 31 Jan 2022 19:18:35 -0800 Message-ID: <7hk0efmfzo.fsf@baylibre.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Hi Saravana, Saravana Kannan writes: > fw_devlink could end up creating device links for bus only devices. > However, bus only devices don't get probed and can block probe() or > sync_state() [1] call backs of other devices. To avoid this, probe these > devices using the simple-pm-bus driver. > > However, there are instances of devices that are not simple buses (they get > probed by their specific drivers) that also list the "simple-bus" (or other > bus only compatible strings) in their compatible property to automatically > populate their child devices. We still want these devices to get probed by > their specific drivers. So, we make sure this driver only probes devices > that are only buses. > > [1] - https://lore.kernel.org/lkml/CAPDyKFo9Bxremkb1dDrr4OcXSpE0keVze94Cm=zrkOVxHHxBmQ@mail.gmail.com/ > Fixes: c442a0d18744 ("driver core: Set fw_devlink to "permissive" behavior by default") > Signed-off-by: Saravana Kannan > Tested-by: Saravana Kannan > Tested-by: Ulf Hansson This patch landed in stable/linux-5.10.y as commit d5f13bbb5104 and it broke suspend/resume on at least one TI AM335x board I'm testing on: upstream dts: arch/arm/boot/dts/am335x-icev2.dts, upstream defconfig: arch/arm/configs/omap2plus_defconfig. Bisecting between vanilla v5.10 (good) and stable/linux-5.10.y (bad) pointed me to this patch, and I confirmed that reverting just this patch on top of stable/linux-5.10.y makes it work again. Also interesting, this same platform works fine on vanilla v5.15, which also includes this patch. That suggests that either 1) this patch should not have been backported to v5.10 stable or 2) there are some other dependencies that are missing in v5.10. Since vanilla v5.10 works fine, I'm leaning towards (1), but if you have any ideas for deps that need backporting, I'm happy to try. I haven't debugged exactly where it's hanging yet, but, enabling CONFIG_DEBUG_DRIVER=y, and suspending with "no_console_suspend" on the command line, the last line before it hangs is: [ 28.129966] simple-pm-bus ocp: noirq power domain suspend Any ideas? Kevin 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 CDF5DC433F5 for ; Tue, 1 Feb 2022 03:18:57 +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:Message-ID:Date:References :In-Reply-To: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=4mIBq2a05ev/VN86RfIsCZOvsRtTXWzTeosozXR1PPM=; b=bvmDQuFpAqhNXY 66PS+wqLGiMbthLUwhfxeo8XFWfL/yf78oKOHyfozPl7+mSZWnGOn6mfgYfgdjqKWai4+PjP5B0g2 0MpBy8/5DPVmF3B6yBYBtAJy/x62xVHvu3dST9XaHZV7BSCP05GigPRVbgJXowk/8IGl9xYYc+NdX IK0cgyJwhKdsY7d9JgHSX1GQDxFPaOj3htaxQchYBh0jaZkQ5nJuIF7C13Fa90r4bq1g496cX/91r yxCbpBryVQCDv2yKO8U/xgzTr97bX+3XVaca/2G4IMciFbYqc5Uiq2wb9Yr2aBxs+rRmozBQJtbvx T4koc3/ZJb54Wm4RkPjg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nEjgq-00B484-7K; Tue, 01 Feb 2022 03:18:44 +0000 Received: from mail-pf1-x432.google.com ([2607:f8b0:4864:20::432]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nEjgm-00B47M-TW for linux-riscv@lists.infradead.org; Tue, 01 Feb 2022 03:18:43 +0000 Received: by mail-pf1-x432.google.com with SMTP id u130so14634251pfc.2 for ; Mon, 31 Jan 2022 19:18:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:in-reply-to:references:date:message-id :mime-version; bh=7ym4guToR5s6XJh+Gyaw0SuEv+LKx7FC/++SseskIfM=; b=E++ef+Q5iBCT3v/I5Xsw8Z42hgWOa0/CD59TDIXkDMY0W82NoIdVaA2wlQHAOqNgPW HVlfHK7n3vd7hCpdQvMsLK+QRFDHf+nMqZyVlPoR39FJ9/sq7mok7WbE7LsSq4UA96gB y4d/Dw5IEj6UGsD60pfH56R5yEmEtlkHe/oa+JG1q70MRkM214E+Q2ZVc2fM23xLE0Rt nhKk1G3dW79j8cHJpcnHjsPzWteJo7l2qH3qiSzZnoOBl9BjPaFQed0VBv+B3JHC4XOO dXEN0f2BkRCdaUQwNKxUlXgbqy2rWF2PXQUOdD42KKaisUfUC2EeMsCfLbv2tZHgtZuT 824A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=7ym4guToR5s6XJh+Gyaw0SuEv+LKx7FC/++SseskIfM=; b=wrJgeLwllo/mHCjDK8nJj8Kw1eK7eLVMjiAq0zUnbiCvWSf66JNrR0AFk1KgZhybln pScmAdkER/WixJ/Ol0+CcI6iKq92r8HVcIIfceCFSEFHl0kxzru4pbtpdMSr23yrieL+ pHVQyS9cmYIaM0SE3FGq4lysiznSUcYmS8H+FhFYrGPw4Gcpq8k1oTg/lGO8UJnbWXy8 9AkqmwCBaYK5EHAYF6V2YSuZ3xm9j37zFjEP99OrGx81NXoZgxnkSIisCuVuZ6qaAg+5 SzuIxktvI8XpYeirQYulOp+DJB3Wpusl9/bM1wrGbJ5U5iT5DPjjbxzWWS5IQEA0VO+0 JUbQ== X-Gm-Message-State: AOAM533P2EUWfkeRKdLKPqmf62EfInfCYnwgT3zB72QLjjy/hV5Fes9T 6kl7eqtYOdU2OuqtmiKYSKvfLQ== X-Google-Smtp-Source: ABdhPJz49oSgsvYX6rVkuwCkpBFyCD/1vuYWgent4FpvFLEF81sRjkDpqWZmQXP+xsW7pCXULByM5A== X-Received: by 2002:a63:2c83:: with SMTP id s125mr15529210pgs.265.1643685516138; Mon, 31 Jan 2022 19:18:36 -0800 (PST) Received: from localhost (c-71-197-186-152.hsd1.wa.comcast.net. [71.197.186.152]) by smtp.gmail.com with ESMTPSA id c8sm13261985pfv.57.2022.01.31.19.18.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 31 Jan 2022 19:18:35 -0800 (PST) From: Kevin Hilman To: Saravana Kannan , Russell King , Neil Armstrong , Geert Uytterhoeven , Magnus Damm , Tony Lindgren , Catalin Marinas , Will Deacon , Damien Le Moal , Greg Kroah-Hartman , Saravana Kannan Cc: Ulf Hansson , Rob Herring , kernel-team@android.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-oxnas@groups.io, linux-renesas-soc@vger.kernel.org, linux-omap@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v4 1/2] drivers: bus: simple-pm-bus: Add support for probing simple bus only devices In-Reply-To: <20210929000735.585237-2-saravanak@google.com> References: <20210929000735.585237-1-saravanak@google.com> <20210929000735.585237-2-saravanak@google.com> Date: Mon, 31 Jan 2022 19:18:35 -0800 Message-ID: <7hk0efmfzo.fsf@baylibre.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220131_191840_980838_7D6540E1 X-CRM114-Status: GOOD ( 16.89 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Hi Saravana, Saravana Kannan writes: > fw_devlink could end up creating device links for bus only devices. > However, bus only devices don't get probed and can block probe() or > sync_state() [1] call backs of other devices. To avoid this, probe these > devices using the simple-pm-bus driver. > > However, there are instances of devices that are not simple buses (they get > probed by their specific drivers) that also list the "simple-bus" (or other > bus only compatible strings) in their compatible property to automatically > populate their child devices. We still want these devices to get probed by > their specific drivers. So, we make sure this driver only probes devices > that are only buses. > > [1] - https://lore.kernel.org/lkml/CAPDyKFo9Bxremkb1dDrr4OcXSpE0keVze94Cm=zrkOVxHHxBmQ@mail.gmail.com/ > Fixes: c442a0d18744 ("driver core: Set fw_devlink to "permissive" behavior by default") > Signed-off-by: Saravana Kannan > Tested-by: Saravana Kannan > Tested-by: Ulf Hansson This patch landed in stable/linux-5.10.y as commit d5f13bbb5104 and it broke suspend/resume on at least one TI AM335x board I'm testing on: upstream dts: arch/arm/boot/dts/am335x-icev2.dts, upstream defconfig: arch/arm/configs/omap2plus_defconfig. Bisecting between vanilla v5.10 (good) and stable/linux-5.10.y (bad) pointed me to this patch, and I confirmed that reverting just this patch on top of stable/linux-5.10.y makes it work again. Also interesting, this same platform works fine on vanilla v5.15, which also includes this patch. That suggests that either 1) this patch should not have been backported to v5.10 stable or 2) there are some other dependencies that are missing in v5.10. Since vanilla v5.10 works fine, I'm leaning towards (1), but if you have any ideas for deps that need backporting, I'm happy to try. I haven't debugged exactly where it's hanging yet, but, enabling CONFIG_DEBUG_DRIVER=y, and suspending with "no_console_suspend" on the command line, the last line before it hangs is: [ 28.129966] simple-pm-bus ocp: noirq power domain suspend Any ideas? Kevin _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv 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 BDE2AC433F5 for ; Tue, 1 Feb 2022 03:20:22 +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:Message-ID:Date:References :In-Reply-To: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=3F1l8cePttFU6ri7+f85ig+t3DMGJgLEJ+XajeXiLbI=; b=J0aUtkTPmWHjNe UXGRnj6y06t8qfn1Q42eFFFhL2HEB1lprKyDD5icuJAidlALuTabRHVji4tpAl26f330/18uD7BM8 s9lsBhywWBu6ofI5bhj8FC+hpjc4YP8dEQen0tNdP20YELQCUL9FFclK4ObkuG5mYKmuvIEH32JYa s6vBEBRo9qweVdGuzbpBy7S6erKbAyE0bVA4gLDqNGnabgZwd+th/KTpC08VIDTjXvF9veN6z/ekp /WCLUQ6e2ZyXZ1ab/ViE8J9+i92XrypfIXBW2z8JNPO1RCqzUPWobD+urDgTEnoRTtONoGcEGEr9r Trmwy/Ubyv5S4aowy0Xg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nEjgw-00B490-LW; Tue, 01 Feb 2022 03:18:50 +0000 Received: from mail-pf1-x42b.google.com ([2607:f8b0:4864:20::42b]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nEjgt-00B47L-J1 for linux-arm-kernel@lists.infradead.org; Tue, 01 Feb 2022 03:18:49 +0000 Received: by mail-pf1-x42b.google.com with SMTP id a8so14615479pfa.6 for ; Mon, 31 Jan 2022 19:18:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:in-reply-to:references:date:message-id :mime-version; bh=7ym4guToR5s6XJh+Gyaw0SuEv+LKx7FC/++SseskIfM=; b=E++ef+Q5iBCT3v/I5Xsw8Z42hgWOa0/CD59TDIXkDMY0W82NoIdVaA2wlQHAOqNgPW HVlfHK7n3vd7hCpdQvMsLK+QRFDHf+nMqZyVlPoR39FJ9/sq7mok7WbE7LsSq4UA96gB y4d/Dw5IEj6UGsD60pfH56R5yEmEtlkHe/oa+JG1q70MRkM214E+Q2ZVc2fM23xLE0Rt nhKk1G3dW79j8cHJpcnHjsPzWteJo7l2qH3qiSzZnoOBl9BjPaFQed0VBv+B3JHC4XOO dXEN0f2BkRCdaUQwNKxUlXgbqy2rWF2PXQUOdD42KKaisUfUC2EeMsCfLbv2tZHgtZuT 824A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=7ym4guToR5s6XJh+Gyaw0SuEv+LKx7FC/++SseskIfM=; b=avhoEdnI8UFkP4jCJmSJx5Fzu39hvqiQFQtDKge+8iosGST9kKRPJ9XZ+RYWsYdqp5 yzR877Bl2y0WkGfj4RTex3EEV+6pb9nCx/rdlat8nQNMENwO/OmCIpzmeHNMXg+lWI07 Y7kXz9L7qf17iben0KcBItf6gxcSaWI/ajH7tUbGII7X/U60zWgFdTA77irE4TRPHK01 SY+/jakkQvJpk+w7UqNtXUIWUGszs6+xcwWc27Op0jq79psSA2Q2RMs1GpVmAuLfXBhG b8/LGTa8ur8xZn2CGbtew0CswdPv85ekvQNK5FbV8IN/t+ciynrtHFtE29t73XylRO+t EaKQ== X-Gm-Message-State: AOAM53240+cHz/XTQhEHQcdAjdyjDzywIoEJwaT9s9uuRQmU5RfKFXUz aDG0O/6YPGUaS7WjGPN9uqg6lA== X-Google-Smtp-Source: ABdhPJz49oSgsvYX6rVkuwCkpBFyCD/1vuYWgent4FpvFLEF81sRjkDpqWZmQXP+xsW7pCXULByM5A== X-Received: by 2002:a63:2c83:: with SMTP id s125mr15529210pgs.265.1643685516138; Mon, 31 Jan 2022 19:18:36 -0800 (PST) Received: from localhost (c-71-197-186-152.hsd1.wa.comcast.net. [71.197.186.152]) by smtp.gmail.com with ESMTPSA id c8sm13261985pfv.57.2022.01.31.19.18.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 31 Jan 2022 19:18:35 -0800 (PST) From: Kevin Hilman To: Saravana Kannan , Russell King , Neil Armstrong , Geert Uytterhoeven , Magnus Damm , Tony Lindgren , Catalin Marinas , Will Deacon , Damien Le Moal , Greg Kroah-Hartman , Saravana Kannan Cc: Ulf Hansson , Rob Herring , kernel-team@android.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-oxnas@groups.io, linux-renesas-soc@vger.kernel.org, linux-omap@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v4 1/2] drivers: bus: simple-pm-bus: Add support for probing simple bus only devices In-Reply-To: <20210929000735.585237-2-saravanak@google.com> References: <20210929000735.585237-1-saravanak@google.com> <20210929000735.585237-2-saravanak@google.com> Date: Mon, 31 Jan 2022 19:18:35 -0800 Message-ID: <7hk0efmfzo.fsf@baylibre.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220131_191847_638110_E674F66E X-CRM114-Status: GOOD ( 18.41 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Saravana, Saravana Kannan writes: > fw_devlink could end up creating device links for bus only devices. > However, bus only devices don't get probed and can block probe() or > sync_state() [1] call backs of other devices. To avoid this, probe these > devices using the simple-pm-bus driver. > > However, there are instances of devices that are not simple buses (they get > probed by their specific drivers) that also list the "simple-bus" (or other > bus only compatible strings) in their compatible property to automatically > populate their child devices. We still want these devices to get probed by > their specific drivers. So, we make sure this driver only probes devices > that are only buses. > > [1] - https://lore.kernel.org/lkml/CAPDyKFo9Bxremkb1dDrr4OcXSpE0keVze94Cm=zrkOVxHHxBmQ@mail.gmail.com/ > Fixes: c442a0d18744 ("driver core: Set fw_devlink to "permissive" behavior by default") > Signed-off-by: Saravana Kannan > Tested-by: Saravana Kannan > Tested-by: Ulf Hansson This patch landed in stable/linux-5.10.y as commit d5f13bbb5104 and it broke suspend/resume on at least one TI AM335x board I'm testing on: upstream dts: arch/arm/boot/dts/am335x-icev2.dts, upstream defconfig: arch/arm/configs/omap2plus_defconfig. Bisecting between vanilla v5.10 (good) and stable/linux-5.10.y (bad) pointed me to this patch, and I confirmed that reverting just this patch on top of stable/linux-5.10.y makes it work again. Also interesting, this same platform works fine on vanilla v5.15, which also includes this patch. That suggests that either 1) this patch should not have been backported to v5.10 stable or 2) there are some other dependencies that are missing in v5.10. Since vanilla v5.10 works fine, I'm leaning towards (1), but if you have any ideas for deps that need backporting, I'm happy to try. I haven't debugged exactly where it's hanging yet, but, enabling CONFIG_DEBUG_DRIVER=y, and suspending with "no_console_suspend" on the command line, the last line before it hangs is: [ 28.129966] simple-pm-bus ocp: noirq power domain suspend Any ideas? Kevin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel