| Message ID | 20210929013719.25120-4-yong.wu@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Clean up "mediatek,larb" | expand |
On 29.09.21 03:37, Yong Wu wrote: > 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 > --- > 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 > } > 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; > } >
On Wed, 2021-09-29 at 18:33 +0200, Dafna Hirschfeld wrote: > > On 29.09.21 03:37, Yong Wu wrote: > > 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 > > --- > > 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? This is probe function, Is it possible the platform device is not ready at this time? I checked the platform device should be created at: of_platform_default_populate_init: arch_initcall_sync ->of_platform_populate ->of_platform_device_create_pdata Not sure if this may be delayed for some device. If not, it should be ENODEV here. > so we should return -ENODEV in that case? > > thanks, > Dafna > > > } > > 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; > > } > > > > _______________________________________________ > Linux-mediatek mailing list > Linux-mediatek@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-mediatek
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; } 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; }