dmaengine: at_xdma: handle errors of at_xdmac_alloc_desc() correctly

It seems that it is valid to have less than the requested number of descriptors. But what is not valid and leads to subsequent errors is to have zero descriptors. In that case, abort the probing. Fixes: e1f7c9e ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver") Signed-off-by: Michael Walle <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Vinod Koul <[email protected]>
fracktal · Jul 5, 2022 · 3770d92 · 3770d92
1 parent 09f7b80
commit 3770d92
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
@@ -1900,6 +1900,11 @@ static int at_xdmac_alloc_chan_resources(struct dma_chan *chan)
 	for (i = 0; i < init_nr_desc_per_channel; i++) {
 		desc = at_xdmac_alloc_desc(chan, GFP_KERNEL);
 		if (!desc) {
+			if (i == 0) {
+				dev_warn(chan2dev(chan),
+					 "can't allocate any descriptors\n");
+				return -EIO;
+			}
 			dev_warn(chan2dev(chan),
 				"only %d descriptors have been allocated\n", i);
 			break;