media: iommu/mediatek: Add probe_defer for smi-larb
authorYong Wu <yong.wu@mediatek.com>
Mon, 17 Jan 2022 07:05:01 +0000 (08:05 +0100)
committerMauro Carvalho Chehab <mchehab@kernel.org>
Fri, 28 Jan 2022 14:30:21 +0000 (15:30 +0100)
commit7d09aaf831b35ab62c5c24efbe716b8f60ad46ad
tree96f43518665302c8e368c515237148a341b87468
parent2fb0feed51085db77606de9b9477c96894328809
media: iommu/mediatek: Add probe_defer for smi-larb

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 <frank-w@public-files.de> # BPI-R2/MT7623
Acked-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
drivers/iommu/mtk_iommu.c
drivers/iommu/mtk_iommu_v1.c