dmaengine: xilinx_dma: check for invalid vdma interleaved parameters

The VDMA HSIZE register (corresponding to sgl[0].size) is only 16bit wide /
the VSIZE register (corresponding to numf) is only 13bit wide, so reject
requests not fitting within that rather than silently transferring too
little data.

Signed-off-by: Peter Korsgaard <[e-mail]>
Reviewed-by: Radhey Shyam Pandey <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/xilinx/xilinx_dma.c

···
 
 /* Register Direct Mode Registers */
 #define XILINX_DMA_REG_VSIZE			0x0000
+#define XILINX_DMA_VSIZE_MASK			GENMASK(12, 0)
 #define XILINX_DMA_REG_HSIZE			0x0004
+#define XILINX_DMA_HSIZE_MASK			GENMASK(15, 0)
 
 #define XILINX_DMA_REG_FRMDLY_STRIDE		0x0008
 #define XILINX_DMA_FRMDLY_STRIDE_FRMDLY_SHIFT	24
···
 		return NULL;
 
 	if (!xt->numf || !xt->sgl[0].size)
+		return NULL;
+
+	if (xt->numf & ~XILINX_DMA_VSIZE_MASK ||
+	    xt->sgl[0].size & ~XILINX_DMA_HSIZE_MASK)
 		return NULL;
 
 	if (xt->frame_size != 1)