[PATCH 4.4 133/312] mtd: nand: pxa3xx_nand: fix dmaengine initialization

From: Greg Kroah-Hartman
Date: Fri May 08 2020 - 08:41:39 EST


From: Robert Jarzmik <robert.jarzmik@xxxxxxx>

commit 9097103f06332d099c5ab06d1e7f22f4bcaca6e2 upstream.

When the driver is initialized in a pure device-tree platform, the
driver's probe fails allocating the dma channel :
[ 525.624435] pxa3xx-nand 43100000.nand: no resource defined for data DMA
[ 525.632088] pxa3xx-nand 43100000.nand: alloc nand resource failed

The reason is that the DMA IO resource is not acquired through platform
resources but by OF bindings.

Fix this by ensuring that DMA IO resources are only queried in the non
device-tree case.

Fixes: 8f5ba31aa565 ("mtd: nand: pxa3xx-nand: switch to dmaengine")
Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
Acked-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Brian Norris <computersforpeace@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mtd/nand/pxa3xx_nand.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/mtd/nand/pxa3xx_nand.c
+++ b/drivers/mtd/nand/pxa3xx_nand.c
@@ -1750,7 +1750,7 @@ static int alloc_nand_resource(struct pl
if (ret < 0)
return ret;

- if (use_dma) {
+ if (!np && use_dma) {
r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
if (r == NULL) {
dev_err(&pdev->dev,