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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F973C43217 for ; Fri, 12 Nov 2021 10:56:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 692F660EFD for ; Fri, 12 Nov 2021 10:56:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234577AbhKLK7K (ORCPT ); Fri, 12 Nov 2021 05:59:10 -0500 Received: from mailgw02.mediatek.com ([210.61.82.184]:41038 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S233619AbhKLK7I (ORCPT ); Fri, 12 Nov 2021 05:59:08 -0500 X-UUID: 60ded804906d4400bf9ac0af5d1c1ced-20211112 X-UUID: 60ded804906d4400bf9ac0af5d1c1ced-20211112 Received: from mtkexhb02.mediatek.inc [(172.21.101.103)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 663950336; Fri, 12 Nov 2021 18:56:15 +0800 Received: from mtkcas10.mediatek.inc (172.21.101.39) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.3; Fri, 12 Nov 2021 18:56:13 +0800 Received: from localhost.localdomain (10.17.3.154) by mtkcas10.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Fri, 12 Nov 2021 18:56:11 +0800 From: Yong Wu To: Matthias Brugger , Joerg Roedel , Rob Herring , Krzysztof Kozlowski , David Airlie , "Mauro Carvalho Chehab" CC: Evan Green , Robin Murphy , Tomasz Figa , Will Deacon , , , , , , , , , Matthias Kaehlcke , , , , , , Daniel Vetter , Chun-Kuang Hu , Philipp Zabel , Tiffany Lin , "Dafna Hirschfeld" , Hsin-Yi Wang , Eizan Miyamoto , , Frank Wunderlich , , , Subject: [PATCH v9 04/15] iommu/mediatek: Add probe_defer for smi-larb Date: Fri, 12 Nov 2021 18:54:58 +0800 Message-ID: <20211112105509.12010-5-yong.wu@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20211112105509.12010-1-yong.wu@mediatek.com> References: <20211112105509.12010-1-yong.wu@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Prepare for adding device_link. The iommu consumer should use device_link to connect with the smi-larb(supplier). then the smi-larb should run before the iommu consumer. Here we delay the iommu driver until the smi driver is ready, then all the iommu consumers always are after the smi driver. When there is no this patch, if some consumer drivers run before smi-larb, the supplier link_status is DL_DEV_NO_DRIVER(0) in the device_link_add, then device_links_driver_bound will use WARN_ON to complain that the link_status of supplier is not right. device_is_bound may be more elegant here. but it is not allowed to EXPORT from https://lore.kernel.org/patchwork/patch/1334670/. Signed-off-by: Yong Wu Tested-by: Frank Wunderlich # BPI-R2/MT7623 --- drivers/iommu/mtk_iommu.c | 4 ++++ drivers/iommu/mtk_iommu_v1.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 8f566d2e72e5..0033c0634e5e 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -848,6 +848,10 @@ static int mtk_iommu_probe(struct platform_device *pdev) of_node_put(larbnode); return -ENODEV; } + if (!plarbdev->dev.driver) { + of_node_put(larbnode); + return -EPROBE_DEFER; + } data->larb_imu[id].dev = &plarbdev->dev; component_match_add_release(dev, &match, release_of, diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index 68bf02f87cfd..4089077256f4 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -606,6 +606,10 @@ static int mtk_iommu_probe(struct platform_device *pdev) of_node_put(larbnode); return -ENODEV; } + if (!plarbdev->dev.driver) { + of_node_put(larbnode); + return -EPROBE_DEFER; + } data->larb_imu[i].dev = &plarbdev->dev; component_match_add_release(dev, &match, release_of, -- 2.18.0