dmaengine: xilinx_dma: Fix uninitialized addr_width when "xlnx,addrwidth" property is missing

When device tree lacks optional "xlnx,addrwidth" property, the addr_width
variable remained uninitialized with garbage values, causing incorrect
DMA mask configuration and subsequent probe failure. The fix ensures a
fallback to the default 32-bit address width when this property is missing.

Signed-off-by: Suraj Gupta <suraj.gupta2@amd.com>
Fixes: b72db40 ("dmaengine: vdma: Add 64 bit addressing support to the driver")
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Reviewed-by: Folker Schwesinger <dev@folker-schwesinger.de>
Link: https://patch.msgid.link/20251021183006.3434495-1-suraj.gupta2@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Author: Suraj Gupta

drivers/dma/xilinx/xilinx_dma.c

@@ -131,6 +131,7 @@
 #define XILINX_MCDMA_MAX_CHANS_PER_DEVICE	0x20
 #define XILINX_DMA_MAX_CHANS_PER_DEVICE		0x2
 #define XILINX_CDMA_MAX_CHANS_PER_DEVICE	0x1
+#define XILINX_DMA_DFAULT_ADDRWIDTH		0x20
 
 #define XILINX_DMA_DMAXR_ALL_IRQ_MASK	\
 		(XILINX_DMA_DMASR_FRM_CNT_IRQ | \
@@ -3159,7 +3160,7 @@ static int xilinx_dma_probe(struct platform_device *pdev)
 	struct device_node *node = pdev->dev.of_node;
 	struct xilinx_dma_device *xdev;
 	struct device_node *child, *np = pdev->dev.of_node;
-	u32 num_frames, addr_width, len_width;
+	u32 num_frames, addr_width = XILINX_DMA_DFAULT_ADDRWIDTH, len_width;
 	int i, err;
 
 	/* Allocate and initialize the DMA engine structure */
@@ -3235,7 +3236,9 @@ static int xilinx_dma_probe(struct platform_device *pdev)
 
 	err = of_property_read_u32(node, "xlnx,addrwidth", &addr_width);
 	if (err < 0)
-		dev_warn(xdev->dev, "missing xlnx,addrwidth property\n");
+		dev_warn(xdev->dev,
+			 "missing xlnx,addrwidth property, using default value %d\n",
+			 XILINX_DMA_DFAULT_ADDRWIDTH);
 
 	if (addr_width > 32)
 		xdev->ext_addr = true;