dmaengine: at_xdmac: handle numf > 1

Handle 'numf > 1' case for interleaved mode.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 50 insertions, 54 deletions

diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index a165b4bfd330..0190d1ca3004 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -929,13 +929,19 @@ at_xdmac_prep_interleaved(struct dma_chan *chan,
 {
         struct at_xdmac_chan    *atchan = to_at_xdmac_chan(chan);
         struct at_xdmac_desc    *prev = NULL, *first = NULL;
-        struct data_chunk       *chunk, *prev_chunk = NULL;
         dma_addr_t              dst_addr, src_addr;
-        size_t                  dst_skip, src_skip, len = 0;
-        size_t                  prev_dst_icg = 0, prev_src_icg = 0;
+        size_t                  src_skip = 0, dst_skip = 0, len = 0;
+        struct data_chunk       *chunk;
         int                     i;
 
-        if (!xt || (xt->numf != 1) || (xt->dir != DMA_MEM_TO_MEM))
+        if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM))
+                return NULL;
+
+        /*
+         * TODO: Handle the case where we have to repeat a chain of
+         * descriptors...
+         */
+        if ((xt->numf > 1) && (xt->frame_size > 1))
                 return NULL;
 
         dev_dbg(chan2dev(chan), "%s: src=0x%08x, dest=0x%08x, numf=%d, frame_size=%d, flags=0x%lx\n",
@@ -945,66 +951,56 @@ at_xdmac_prep_interleaved(struct dma_chan *chan,
         src_addr = xt->src_start;
         dst_addr = xt->dst_start;
 
-        for (i = 0; i < xt->frame_size; i++) {
-                struct at_xdmac_desc *desc;
-                size_t src_icg, dst_icg;
-
-                chunk = xt->sgl + i;
+        if (xt->numf > 1) {
+                first = at_xdmac_interleaved_queue_desc(chan, atchan,
+                                                        NULL,
+                                                        src_addr, dst_addr,
+                                                        xt, xt->sgl);
+                for (i = 0; i < xt->numf; i++)
+                        at_xdmac_increment_block_count(chan, first);
+        } else {
+                for (i = 0; i < xt->frame_size; i++) {
+                        size_t src_icg = 0, dst_icg = 0;
+                        struct at_xdmac_desc *desc;
 
-                dst_icg = dmaengine_get_dst_icg(xt, chunk);
-                src_icg = dmaengine_get_src_icg(xt, chunk);
+                        chunk = xt->sgl + i;
 
-                src_skip = chunk->size + src_icg;
-                dst_skip = chunk->size + dst_icg;
+                        dst_icg = dmaengine_get_dst_icg(xt, chunk);
+                        src_icg = dmaengine_get_src_icg(xt, chunk);
 
-                dev_dbg(chan2dev(chan),
-                        "%s: chunk size=%d, src icg=%d, dst icg=%d\n",
-                        __func__, chunk->size, src_icg, dst_icg);
+                        src_skip = chunk->size + src_icg;
+                        dst_skip = chunk->size + dst_icg;
 
-                /*
-                 * Handle the case where we just have the same
-                 * transfer to setup, we can just increase the
-                 * block number and reuse the same descriptor.
-                 */
-                if (prev_chunk && prev &&
-                    (prev_chunk->size == chunk->size) &&
-                    (prev_src_icg == src_icg) &&
-                    (prev_dst_icg == dst_icg)) {
                         dev_dbg(chan2dev(chan),
-                                "%s: same configuration that the previous chunk, merging the descriptors...\n",
-                                __func__);
-                        at_xdmac_increment_block_count(chan, prev);
-                        continue;
-                }
-
-                desc = at_xdmac_interleaved_queue_desc(chan, atchan,
-                                                       prev,
-                                                       src_addr, dst_addr,
-                                                       xt, chunk);
-                if (!desc) {
-                        list_splice_init(&first->descs_list,
-                                         &atchan->free_descs_list);
-                        return NULL;
-                }
+                                "%s: chunk size=%d, src icg=%d, dst icg=%d\n",
+                                __func__, chunk->size, src_icg, dst_icg);
+
+                        desc = at_xdmac_interleaved_queue_desc(chan, atchan,
+                                                               prev,
+                                                               src_addr, dst_addr,
+                                                               xt, chunk);
+                        if (!desc) {
+                                list_splice_init(&first->descs_list,
+                                                 &atchan->free_descs_list);
+                                return NULL;
+                        }
 
-                if (!first)
-                        first = desc;
+                        if (!first)
+                                first = desc;
 
-                dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
-                        __func__, desc, first);
-                list_add_tail(&desc->desc_node, &first->descs_list);
+                        dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
+                                __func__, desc, first);
+                        list_add_tail(&desc->desc_node, &first->descs_list);
 
-                if (xt->src_sgl)
-                        src_addr += src_skip;
+                        if (xt->src_sgl)
+                                src_addr += src_skip;
 
-                if (xt->dst_sgl)
-                        dst_addr += dst_skip;
+                        if (xt->dst_sgl)
+                                dst_addr += dst_skip;
 
-                len += chunk->size;
-                prev_chunk = chunk;
-                prev_dst_icg = dst_icg;
-                prev_src_icg = src_icg;
-                prev = desc;
+                        len += chunk->size;
+                        prev = desc;
+                }
         }
 
         first->tx_dma_desc.cookie = -EBUSY;