iommu/of: Remove PCI host bridge node check

of_pci_iommu_init() tries to be clever and stop its alias walk at the
device represented by master_np, in case of weird PCI topologies where
the bridge to the IOMMU and the rest of the system is not at the root.
It turns out this is a bit short-sighted, since there are plenty of
other callers of pci_for_each_dma_alias() which would also need the same
behaviour in that situation, and the only platform so far with such a
topology (Cavium ThunderX2) already solves it more generally via a PCI
quirk. As this check is effectively redundant, and returning a boolean
value as an int is a bit broken anyway, let's just get rid of it.

Reported-by: Jean-Philippe Brucker <[email protected]>
Fixes: d87beb7 ("iommu/of: Handle PCI aliases properly")
Signed-off-by: Robin Murphy <[email protected]>
Tested-by: Jean-Philippe Brucker <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>

drivers/iommu/of_iommu.c

@@ -157,10 +157,7 @@ static int of_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data)
 
 	err = of_iommu_xlate(info->dev, &iommu_spec);
 	of_node_put(iommu_spec.np);
-	if (err)
-		return err;
-
-	return info->np == pdev->bus->dev.of_node;
+	return err;
 }
 
 const struct iommu_ops *of_iommu_configure(struct device *dev,