Re: [PATCH v8 03/12] iommu/mediatek: Add probe_defer for smi-larb
From: Dafna Hirschfeld <hidden>
Date: 2021-09-29 16:33:13
Also in:
dri-devel, linux-arm-kernel, linux-iommu, linux-media, linux-mediatek, lkml
On 29.09.21 03:37, Yong Wu wrote:
quoted hunk ↗ jump to hunk
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 <yong.wu@mediatek.com> Tested-by: Frank Wunderlich <redacted> # BPI-R2/MT7623 --- drivers/iommu/mtk_iommu.c | 2 +- drivers/iommu/mtk_iommu_v1.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index d837adfd1da5..d5848f78a677 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c@@ -844,7 +844,7 @@ static int mtk_iommu_probe(struct platform_device *pdev) id = i; plarbdev = of_find_device_by_node(larbnode); - if (!plarbdev) { + if (!plarbdev || !plarbdev->dev.driver) { of_node_put(larbnode); return -EPROBE_DEFER;
if plarbdev is null doesn't that mean that the device does not exist? so we should return -ENODEV in that case? thanks, Dafna
quoted hunk ↗ jump to hunk
}diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index 1467ba1e4417..4d7809432239 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c@@ -602,7 +602,7 @@ static int mtk_iommu_probe(struct platform_device *pdev) } plarbdev = of_find_device_by_node(larbnode); - if (!plarbdev) { + if (!plarbdev || !plarbdev->dev.driver) { of_node_put(larbnode); return -EPROBE_DEFER; }