Commit b33cae99 authored May 26, 2022 by Michael Walle Committed by Greg Kroah-Hartman Jul 12, 2022

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: e1f7c9ee ("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>

parent b7bfa649

drivers/dma/at_xdmac.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -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;