dmaengine: at_xdma: handle errors of at_xdmac_alloc_desc() correctly

commit 3770d92bd5237d686e49da7b2fb86f53ee6ed259 upstream.

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: e1f7c9eee7 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver")
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220526135111.1470926-1-michael@walle.cc
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Michael Walle 2022-05-26 15:51:11 +02:00 committed by Greg Kroah-Hartman
parent 7b721f5aec
commit 1be247db20

View File

@ -1838,6 +1838,11 @@ 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;