diff options
| author | Nuno Sá <nuno.sa@analog.com> | 2026-03-03 13:25:02 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2026-03-09 10:28:21 +0300 |
| commit | c60990ba1fb2a6c1ff2789e610aa130f3047a2ff (patch) | |
| tree | 7f690136cfc5fe0e5750923f214897d80c9156d0 | |
| parent | ac85913ab71e0de9827b7f8f7fccb9f20943c02f (diff) | |
| download | linux-c60990ba1fb2a6c1ff2789e610aa130f3047a2ff.tar.xz | |
dmaengine: dma-axi-dmac: Add helper for getting next desc
Add a new helper for getting the next valid struct axi_dmac_desc. This
will be extended in follow up patches to support to gracefully terminate
cyclic transfers.
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Link: https://patch.msgid.link/20260303-axi-dac-cyclic-support-v2-3-0db27b4be95a@analog.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
| -rw-r--r-- | drivers/dma/dma-axi-dmac.c | 33 |
1 files changed, 23 insertions, 10 deletions
diff --git a/drivers/dma/dma-axi-dmac.c b/drivers/dma/dma-axi-dmac.c index 79c01b7d9732..a47e08d3dbbc 100644 --- a/drivers/dma/dma-axi-dmac.c +++ b/drivers/dma/dma-axi-dmac.c @@ -227,10 +227,29 @@ static bool axi_dmac_check_addr(struct axi_dmac_chan *chan, dma_addr_t addr) return true; } +static struct axi_dmac_desc *axi_dmac_get_next_desc(struct axi_dmac *dmac, + struct axi_dmac_chan *chan) +{ + struct virt_dma_desc *vdesc; + struct axi_dmac_desc *desc; + + if (chan->next_desc) + return chan->next_desc; + + vdesc = vchan_next_desc(&chan->vchan); + if (!vdesc) + return NULL; + + list_move_tail(&vdesc->node, &chan->active_descs); + desc = to_axi_dmac_desc(vdesc); + chan->next_desc = desc; + + return desc; +} + static void axi_dmac_start_transfer(struct axi_dmac_chan *chan) { struct axi_dmac *dmac = chan_to_axi_dmac(chan); - struct virt_dma_desc *vdesc; struct axi_dmac_desc *desc; struct axi_dmac_sg *sg; unsigned int flags = 0; @@ -240,16 +259,10 @@ static void axi_dmac_start_transfer(struct axi_dmac_chan *chan) if (val) /* Queue is full, wait for the next SOT IRQ */ return; - desc = chan->next_desc; + desc = axi_dmac_get_next_desc(dmac, chan); + if (!desc) + return; - if (!desc) { - vdesc = vchan_next_desc(&chan->vchan); - if (!vdesc) - 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]; /* Already queued in cyclic mode. Wait for it to finish */ |