From a8817489dc3e3b1910842958a3b9d9e4832e99b0 Mon Sep 17 00:00:00 2001
From: Thierry Reding <treding@nvidia.com>
Date: Tue, 3 Dec 2019 17:19:12 +0100
Subject: drm/tegra: Silence expected errors on IOMMU attach
Git-commit: a8817489dc3e3b1910842958a3b9d9e4832e99b0
Patch-mainline: v5.5-rc1
References: bsc#1152489

Subdevices may not be hooked up to an IOMMU via device tree. Detect such
situations and avoid confusing users by not emitting an error message.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/tegra/dc.c  | 2 +-
 drivers/gpu/drm/tegra/drm.c | 4 +---
 drivers/gpu/drm/tegra/vic.c | 2 +-
 3 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index 85d3c9ad29df..714af052fbef 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -2017,7 +2017,7 @@ static int tegra_dc_init(struct host1x_client *client)
 		dev_warn(dc->dev, "failed to allocate syncpoint\n");
 
 	err = host1x_client_iommu_attach(client);
-	if (err < 0) {
+	if (err < 0 && err != -ENODEV) {
 		dev_err(client->dev, "failed to attach to domain: %d\n", err);
 		return err;
 	}
diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index 56e5e7a5c108..7a16b51eaa2d 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -920,10 +920,8 @@ int host1x_client_iommu_attach(struct host1x_client *client)
 
 	if (tegra->domain) {
 		group = iommu_group_get(client->dev);
-		if (!group) {
-			dev_err(client->dev, "failed to get IOMMU group\n");
+		if (!group)
 			return -ENODEV;
-		}
 
 		if (domain != tegra->domain) {
 			err = iommu_attach_group(tegra->domain, group);
diff --git a/drivers/gpu/drm/tegra/vic.c b/drivers/gpu/drm/tegra/vic.c
index c4d82b8b3065..3526c2892ddb 100644
--- a/drivers/gpu/drm/tegra/vic.c
+++ b/drivers/gpu/drm/tegra/vic.c
@@ -167,7 +167,7 @@ static int vic_init(struct host1x_client *client)
 	int err;
 
 	err = host1x_client_iommu_attach(client);
-	if (err < 0) {
+	if (err < 0 && err != -ENODEV) {
 		dev_err(vic->dev, "failed to attach to domain: %d\n", err);
 		return err;
 	}
-- 
2.28.0