dmaengine: at_xdma: handle errors of at_xdmac_alloc_desc() correctly

commit 3770d92bd5 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 b91312b507
commit bce1b24d66

View file

@ -1804,6 +1804,11 @@ 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_ATOMIC);
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;