From nobody Fri Sep 20 15:34:32 2024 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 394D0C001B0 for ; Mon, 17 Jul 2023 14:15:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229718AbjGQOPI (ORCPT ); Mon, 17 Jul 2023 10:15:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42270 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232157AbjGQOOy (ORCPT ); Mon, 17 Jul 2023 10:14:54 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e5ab]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16CB110E4 for ; Mon, 17 Jul 2023 07:14:50 -0700 (PDT) Received: from IcarusMOD.eternityproject.eu (2-237-20-237.ip236.fastwebnet.it [2.237.20.237]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: kholk11) by madras.collabora.co.uk (Postfix) with ESMTPSA id EDBED660706B; Mon, 17 Jul 2023 15:14:47 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1689603288; bh=vi70p/9FDUxG9+dFVjjeS3h5x0OhHX3G4+djzfe2T7g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EbTkkR0teiWcw05LFQieNjl2W+VC/k26E+DX+Uuw516A3SmmB8jrr1KMI9BSkRmJu BVEcecpOr1DrWMN0kAuwb4U1QwWZfwWAP8iyW43mjFJNe36cmWPj+hZZ8mMGb12sQt Z0aXTsg7mpwvo25MEwhACay3IXEKEY4pMti1nm9qoM/Z4pGs2CPMOmkXjvgxI3mxq+ XEBoO5LqDH3xShkuKrtXQc99Mzjj8JP6K9YFLBWDTc7pAF0QKuqYFEbvDA2GAkXDaU hBp/keqJV8TBZAfLI0ZMzETOjKUlk8jrEjKqFQpLr5Wy/SJqpWO+CvzSo6SBJzbPg7 wq1K4WxwsbkNg== From: AngeloGioacchino Del Regno To: chunkuang.hu@kernel.org Cc: p.zabel@pengutronix.de, airlied@gmail.com, daniel@ffwll.ch, matthias.bgg@gmail.com, angelogioacchino.delregno@collabora.com, dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel@collabora.com, wenst@chromium.org, nfraprado@collabora.com Subject: [PATCH v6 06/11] drm/mediatek: dp: Enable event interrupt only when bridge attached Date: Mon, 17 Jul 2023 16:14:33 +0200 Message-Id: <20230717141438.274419-7-angelogioacchino.delregno@collabora.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230717141438.274419-1-angelogioacchino.delregno@collabora.com> References: <20230717141438.274419-1-angelogioacchino.delregno@collabora.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" It is useless and error-prone to enable the DisplayPort event interrupt before finishing to probe and install the driver, as the DP training cannot happen before the entire pipeline is correctly set up, as the interrupt handler also requires the full hardware to be initialized by mtk_dp_bridge_attach(). Anyway, depending in which state the controller is left from the bootloader, this may cause an interrupt storm and consequently hang the kernel during boot, so, avoid enabling the interrupt until we reach a clean state by adding the IRQ_NOAUTOEN flag before requesting it at probe time and manage the enablement of the ISR in the .attach() and .detach() handlers for the DP bridge. Signed-off-by: AngeloGioacchino Del Regno Tested-by: Chen-Yu Tsai Reviewed-by: Alexandre Mergnat --- drivers/gpu/drm/mediatek/mtk_dp.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/m= tk_dp.c index e8d3bf310608..83e55f8dc84a 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp.c +++ b/drivers/gpu/drm/mediatek/mtk_dp.c @@ -100,6 +100,7 @@ struct mtk_dp_efuse_fmt { struct mtk_dp { bool enabled; bool need_debounce; + int irq; u8 max_lanes; u8 max_linkrate; u8 rx_cap[DP_RECEIVER_CAP_SIZE]; @@ -2141,6 +2142,8 @@ static int mtk_dp_bridge_attach(struct drm_bridge *br= idge, =20 mtk_dp->drm_dev =3D bridge->dev; =20 + irq_clear_status_flags(mtk_dp->irq, IRQ_NOAUTOEN); + enable_irq(mtk_dp->irq); mtk_dp_hwirq_enable(mtk_dp, true); =20 return 0; @@ -2157,6 +2160,7 @@ static void mtk_dp_bridge_detach(struct drm_bridge *b= ridge) struct mtk_dp *mtk_dp =3D mtk_dp_from_bridge(bridge); =20 mtk_dp_hwirq_enable(mtk_dp, false); + disable_irq(mtk_dp->irq); mtk_dp->drm_dev =3D NULL; mtk_dp_poweroff(mtk_dp); drm_dp_aux_unregister(&mtk_dp->aux); @@ -2475,7 +2479,7 @@ static int mtk_dp_probe(struct platform_device *pdev) { struct mtk_dp *mtk_dp; struct device *dev =3D &pdev->dev; - int ret, irq_num; + int ret; =20 mtk_dp =3D devm_kzalloc(dev, sizeof(*mtk_dp), GFP_KERNEL); if (!mtk_dp) @@ -2484,9 +2488,9 @@ static int mtk_dp_probe(struct platform_device *pdev) mtk_dp->dev =3D dev; mtk_dp->data =3D (struct mtk_dp_data *)of_device_get_match_data(dev); =20 - irq_num =3D platform_get_irq(pdev, 0); - if (irq_num < 0) - return dev_err_probe(dev, irq_num, + mtk_dp->irq =3D platform_get_irq(pdev, 0); + if (mtk_dp->irq < 0) + return dev_err_probe(dev, mtk_dp->irq, "failed to request dp irq resource\n"); =20 mtk_dp->next_bridge =3D devm_drm_of_get_bridge(dev, dev->of_node, 1, 0); @@ -2507,7 +2511,8 @@ static int mtk_dp_probe(struct platform_device *pdev) =20 spin_lock_init(&mtk_dp->irq_thread_lock); =20 - ret =3D devm_request_threaded_irq(dev, irq_num, mtk_dp_hpd_event, + irq_set_status_flags(mtk_dp->irq, IRQ_NOAUTOEN); + ret =3D devm_request_threaded_irq(dev, mtk_dp->irq, mtk_dp_hpd_event, mtk_dp_hpd_event_thread, IRQ_TYPE_LEVEL_HIGH, dev_name(dev), mtk_dp); --=20 2.40.1