From patchwork Thu Sep 21 19:26:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 725815 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 70D6BE7D0A6 for ; Thu, 21 Sep 2023 19:49:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231379AbjIUTtI (ORCPT ); Thu, 21 Sep 2023 15:49:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230424AbjIUTsn (ORCPT ); Thu, 21 Sep 2023 15:48:43 -0400 Received: from mail-pl1-x62c.google.com (mail-pl1-x62c.google.com [IPv6:2607:f8b0:4864:20::62c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B90B259F8 for ; Thu, 21 Sep 2023 12:28:41 -0700 (PDT) Received: by mail-pl1-x62c.google.com with SMTP id d9443c01a7336-1c1e3a4a06fso11210835ad.3 for ; Thu, 21 Sep 2023 12:28:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1695324521; x=1695929321; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=iA2li7ELqa/hnFznycO86SuLFz051HXi1UIFyEU+SsY=; b=BGmAnpIi3iuDy812Osm+g+26341LogmDzQhgtW6SO6RxhNh2/Xxh9zdGfTP1dghyfu mwBgbXni0d0hUX2T+0307DGHcjWJjqjCHyQ6333ddP7sLjutHJ8eOWH0AU8ZqzyA5uwe 0tQCgIWsVbv8HjmWYojERkl+ck9leykdb9Cyg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695324521; x=1695929321; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=iA2li7ELqa/hnFznycO86SuLFz051HXi1UIFyEU+SsY=; b=YihBDoDG1hJvpNdSNeyhApsbRC2oKS9TQAreuWHRaJbF6N/qNszASyDWnHr90hlB2U GmIRUmmusDK3ErLKJlgHL7n1O/woU3t6s12uPsjx7RFcfveZMghUeKcPG9tNuKUUEhb6 4tOQnIt/6rZo9Coe3Qz3K3XflL7/SpFU93hxdt1zhf8hweua8Y9BNZ6NszdNB4S3v2yr Aeie5ZM9pDUhUjjgRQXTz5aNWHvXVVYbwysSuvJu7gys4XX1P/A0RAaJPfxQtl/dTgVe emn3e65nHaPtBJK7yxHChs07Ok6wu29E3/4DGzJCzhdh1jI7ldgI/3FEcgdEdnthSe61 K4uw== X-Gm-Message-State: AOJu0YxDlIjFSbRIs8wE50Sryrbh4Kp1BTnDswobes/qY1b9wkcTOh/9 Q0EDoB4j6RFs1pr3lxte2jR42Q== X-Google-Smtp-Source: AGHT+IGqiH8+93CjsgTzwhYDRPl823KLkGG4+0EgU7Nds+tbBUgFbUmFj98SJgfl8Opc5kzECLW4aw== X-Received: by 2002:a17:903:1205:b0:1c4:638:fff4 with SMTP id l5-20020a170903120500b001c40638fff4mr6441686plh.17.1695324521206; Thu, 21 Sep 2023 12:28:41 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:9d:2:e6ed:6d49:f262:8041]) by smtp.gmail.com with ESMTPSA id w8-20020a1709029a8800b001b9f032bb3dsm1892875plp.3.2023.09.21.12.28.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Sep 2023 12:28:40 -0700 (PDT) From: Douglas Anderson To: dri-devel@lists.freedesktop.org, Maxime Ripard Cc: Douglas Anderson , airlied@gmail.com, alim.akhtar@samsung.com, daniel@ffwll.ch, inki.dae@samsung.com, krzysztof.kozlowski@linaro.org, kyungmin.park@samsung.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, sw0312.kim@samsung.com Subject: [RFT PATCH v2 09/12] drm/exynos: Call drm_atomic_helper_shutdown() at shutdown/unbind time Date: Thu, 21 Sep 2023 12:26:52 -0700 Message-ID: <20230921122641.RFT.v2.9.Iea33274908b6b258955f45a8aaf6f5bba24ad6cd@changeid> X-Mailer: git-send-email 2.42.0.515.g380fc7ccd1-goog In-Reply-To: <20230921192749.1542462-1-dianders@chromium.org> References: <20230921192749.1542462-1-dianders@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org Based on grepping through the source code this driver appears to be missing a call to drm_atomic_helper_shutdown() at system shutdown time and at driver unbind time. Among other things, this means that if a panel is in use that it won't be cleanly powered off at system shutdown time. The fact that we should call drm_atomic_helper_shutdown() in the case of OS shutdown/restart and at driver remove (or unbind) time comes straight out of the kernel doc "driver instance overview" in drm_drv.c. A few notes about this fix: - When adding drm_atomic_helper_shutdown() to the unbind path, I added it after drm_kms_helper_poll_fini() since that's when other drivers seemed to have it. - Technically with a previous patch, ("drm/atomic-helper: drm_atomic_helper_shutdown(NULL) should be a noop"), we don't actually need to check to see if our "drm" pointer is NULL before calling drm_atomic_helper_shutdown(). We'll leave the "if" test in, though, so that this patch can land without any dependencies. It could potentially be removed later. - This patch also makes sure to set the drvdata to NULL in the case of bind errors to make sure that shutdown can't access freed data. Suggested-by: Maxime Ripard Reviewed-by: Maxime Ripard Signed-off-by: Douglas Anderson --- This commit is only compile-time tested. (no changes since v1) drivers/gpu/drm/exynos/exynos_drm_drv.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c index 8399256cb5c9..5380fb6c55ae 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_drv.c +++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c @@ -300,6 +300,7 @@ static int exynos_drm_bind(struct device *dev) drm_mode_config_cleanup(drm); exynos_drm_cleanup_dma(drm); kfree(private); + dev_set_drvdata(dev, NULL); err_free_drm: drm_dev_put(drm); @@ -313,6 +314,7 @@ static void exynos_drm_unbind(struct device *dev) drm_dev_unregister(drm); drm_kms_helper_poll_fini(drm); + drm_atomic_helper_shutdown(drm); component_unbind_all(drm->dev, drm); drm_mode_config_cleanup(drm); @@ -350,9 +352,18 @@ static int exynos_drm_platform_remove(struct platform_device *pdev) return 0; } +static void exynos_drm_platform_shutdown(struct platform_device *pdev) +{ + struct drm_device *drm = platform_get_drvdata(pdev); + + if (drm) + drm_atomic_helper_shutdown(drm); +} + static struct platform_driver exynos_drm_platform_driver = { .probe = exynos_drm_platform_probe, .remove = exynos_drm_platform_remove, + .shutdown = exynos_drm_platform_shutdown, .driver = { .name = "exynos-drm", .pm = &exynos_drm_pm_ops,