From: Nuno Sá Date: Tue, 4 Nov 2025 16:22:25 +0000 (+0000) Subject: dma: dma-axi-dmac: fix SW cyclic transfers X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9bd257181fd5c996d922e9991500ad27987cfbf4;p=thirdparty%2Flinux.git dma: dma-axi-dmac: fix SW cyclic transfers If 'hw_cyclic' is false we should still be able to do cyclic transfers in "software". That was not working for the case where 'desc->num_sgs' is 1 because 'chan->next_desc' is never set with the current desc which means that the cyclic transfer only runs once and in the next SOT interrupt we do nothing since vchan_next_desc() will return NULL. Fix it by setting 'chan->next_desc' as soon as we get a new desc via vchan_next_desc(). Fixes: 0e3b67b348b8 ("dmaengine: Add support for the Analog Devices AXI-DMAC DMA controller") Signed-off-by: Nuno Sá base-commit: 398035178503bf662281bbffb4bebce1460a4bc5 change-id: 20251104-axi-dmac-fixes-and-improvs-e3ad512a329c Acked-by: Michael Hennerich Link: https://patch.msgid.link/20251104-axi-dmac-fixes-and-improvs-v1-1-3e6fd9328f72@analog.com Signed-off-by: Vinod Koul --- diff --git a/drivers/dma/dma-axi-dmac.c b/drivers/dma/dma-axi-dmac.c index 5b06b0dc67ee..e22639822045 100644 --- a/drivers/dma/dma-axi-dmac.c +++ b/drivers/dma/dma-axi-dmac.c @@ -247,6 +247,7 @@ static void axi_dmac_start_transfer(struct axi_dmac_chan *chan) return; list_move_tail(&vdesc->node, &chan->active_descs); desc = to_axi_dmac_desc(vdesc); + chan->next_desc = desc; } sg = &desc->sg[desc->num_submitted]; @@ -265,8 +266,6 @@ static void axi_dmac_start_transfer(struct axi_dmac_chan *chan) else chan->next_desc = NULL; flags |= AXI_DMAC_FLAG_LAST; - } else { - chan->next_desc = desc; } sg->hw->id = axi_dmac_read(dmac, AXI_DMAC_REG_TRANSFER_ID);