[PATCH v6 06/12] media: iris: Skip DMA mask setup when the core device has no IOMMU

[Vikash Garodia]

Once the streams are described as context bank subnodes, the "iommus"
property no longer sits on the parent iris node. That device then has no
IOMMU domain of its own and never performs DMA directly, so calling
dma_set_mask_and_coherent() on it is meaningless, and on a device with no
IOMMU it can fail and abort probe.

Set the DMA mask only when device_iommu_mapped() reports an IOMMU on the
core device. Platforms that have not been converted still carry "iommus"
on the parent node and keep the existing setup. For converted platforms
the mask is applied to each context bank device instead, in
iris_create_cb_dev().

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
Co-developed-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
Signed-off-by: Vikash Garodia <vikash.garodia@xxxxxxxxxxxxxxxx>
---
 drivers/media/platform/qcom/iris/iris_probe.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/qcom/iris/iris_probe.c b/drivers/media/platform/qcom/iris/iris_probe.c
index e659461716ba46c84d616b41f477b6250d46bd81..6d7147d73d40b08cbcd55ea5a19ec57d0738abf0 100644
--- a/drivers/media/platform/qcom/iris/iris_probe.c
+++ b/drivers/media/platform/qcom/iris/iris_probe.c
@@ -154,6 +154,9 @@ static void iris_unreserve_iova_region(struct device *dev, struct dma_iova_state
 {
 	unsigned int i;
 
+	if (!device_iommu_mapped(dev))
+		return;
+
 	for (i = 0; dma_iova_size(&iova_state[i]); i++)
 		dma_iova_free(dev, &iova_state[i]);
 }
@@ -167,6 +170,9 @@ static int iris_reserve_iova_region(struct device *dev, struct dma_iova_state **
 	unsigned int count = 0;
 	int ret = -ENOMEM;
 
+	if (!device_iommu_mapped(dev))
+		return 0;
+
 	state = devm_kcalloc(dev, BITS_PER_TYPE(dma_addr_t) + 1, sizeof(*state), GFP_KERNEL);
 	if (!state)
 		return ret;
@@ -433,9 +439,11 @@ static int iris_probe(struct platform_device *pdev)
 
 	dma_mask = core->iris_platform_data->dma_mask;
 
-	ret = dma_set_mask_and_coherent(dev, dma_mask);
-	if (ret)
-		goto err_vdev_unreg_enc;
+	if (device_iommu_mapped(dev)) {
+		ret = dma_set_mask_and_coherent(dev, dma_mask);
+		if (ret)
+			goto err_vdev_unreg_enc;
+	}
 
 	dma_set_max_seg_size(&pdev->dev, DMA_BIT_MASK(32));
 	dma_set_seg_boundary(&pdev->dev, DMA_BIT_MASK(32));

-- 
2.34.1