[PATCH RFC 03/11] dmaengine: bcm2835: Support common dma-channel-mask

Stefan Wahren stefan.wahren at i2se.com
Mon Dec 27 04:05:37 PST 2021


Nowadays there is a generic property for dma-channel-mask in the DMA
controller binding. So prefer this one instead of the old vendor specific
one. Print a warning in case the old one is used. Btw use the result of
of_property_read_u32() as return code in error case.

Signed-off-by: Stefan Wahren <stefan.wahren at i2se.com>
---
 drivers/dma/bcm2835-dma.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c
index 630dfbb..adfe6bc 100644
--- a/drivers/dma/bcm2835-dma.c
+++ b/drivers/dma/bcm2835-dma.c
@@ -943,12 +943,19 @@ static int bcm2835_dma_probe(struct platform_device *pdev)
 	}
 
 	/* Request DMA channel mask from device tree */
-	if (of_property_read_u32(pdev->dev.of_node,
-			"brcm,dma-channel-mask",
-			&chans_available)) {
-		dev_err(&pdev->dev, "Failed to get channel mask\n");
-		rc = -EINVAL;
-		goto err_no_dma;
+	rc = of_property_read_u32(pdev->dev.of_node, "dma-channel-mask",
+				  &chans_available);
+
+	if (rc) {
+		/* Try deprecated property */
+		if (of_property_read_u32(pdev->dev.of_node,
+					 "brcm,dma-channel-mask",
+					 &chans_available)) {
+			dev_err(&pdev->dev, "Failed to get channel mask\n");
+			goto err_no_dma;
+		}
+
+		dev_warn(&pdev->dev, "Please update DT blob\n");
 	}
 
 	/* get irqs for each channel that we support */
-- 
2.7.4




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