Provide individual device drivers the chance to gracefully refuse to attach a device to the default domain. If the attach_device op returns -ENOTSUPP don't print a error message and don't set group->domain but still return success from iommu_group_add_dev().
This allows all the usual APIs to work and the next domain to try to attach will take group->domain for itself and everything will proceed as normal. Signed-off-by: Jordan Crouse <[email protected]> --- drivers/iommu/iommu.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 0ba3d27f2300..a255b5d6c495 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -599,7 +599,7 @@ int iommu_group_add_device(struct iommu_group *group, struct device *dev) if (group->domain) ret = __iommu_attach_device(group->domain, dev); mutex_unlock(&group->mutex); - if (ret) + if (ret && ret != -ENOTSUPP) goto err_put_group; /* Notify any listeners about change to group. */ @@ -625,7 +625,8 @@ int iommu_group_add_device(struct iommu_group *group, struct device *dev) sysfs_remove_link(&dev->kobj, "iommu_group"); err_free_device: kfree(device); - pr_err("Failed to add device %s to group %d: %d\n", dev_name(dev), group->id, ret); + if (ret != -ENOTSUPP) + pr_err("Failed to add device %s to group %d: %d\n", dev_name(dev), group->id, ret); return ret; } EXPORT_SYMBOL_GPL(iommu_group_add_device); @@ -1238,8 +1239,16 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev) ret = iommu_group_add_device(group, dev); if (ret) { - iommu_group_put(group); - return ERR_PTR(ret); + /* + * If the driver chooses not to bind the device, reset + * group->domain so a new domain can be added later + */ + if (ret == -ENOTSUPP) + group->domain = NULL; + else { + iommu_group_put(group); + return ERR_PTR(ret); + } } return group; -- 2.17.0 _______________________________________________ Freedreno mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/freedreno
