[PATCH v3] drm/mediatek: Stop using iommu_present()

Robin Murphy robin.murphy at arm.com
Thu Nov 23 05:41:12 PST 2023


Remove the pointless check. If an IOMMU is providing transparent DMA API
ops for any device(s) we care about, the DT code will have enforced the
appropriate probe ordering already. And if the IOMMU *is* entirely
absent, then attempting to go ahead with CMA and either suceeding or
failing decisively seems more useful than deferring forever.

Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---

I realised that last time I sent this I probably should have CCed a
wider audience of reviewers, so here's one with an updated commit
message as well to make the resend more worthwhile.

 drivers/gpu/drm/mediatek/mtk_drm_drv.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index 2dfaa613276a..48581da51857 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -5,7 +5,6 @@
  */
 
 #include <linux/component.h>
-#include <linux/iommu.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
@@ -608,9 +607,6 @@ static int mtk_drm_bind(struct device *dev)
 	struct drm_device *drm;
 	int ret, i;
 
-	if (!iommu_present(&platform_bus_type))
-		return -EPROBE_DEFER;
-
 	pdev = of_find_device_by_node(private->mutex_node);
 	if (!pdev) {
 		dev_err(dev, "Waiting for disp-mutex device %pOF\n",
-- 
2.39.2.101.g768bb238c484.dirty




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