dmaengine: remove DMA_MEMCPY_SG once again

This was removed before due to the complete lack of users, but
3218910fd585 ("dmaengine: Add core function and capability check for
DMA_MEMCPY_SG") and 29cf37fa6dd9 ("dmaengine: Add consumer for the new
DMA_MEMCPY_SG API function.") added it back despite still not having
any users whatsoever.

Fixes: 3218910fd585 ("dmaengine: Add core function and capability check for DMA_MEMCPY_SG")
Fixes: 29cf37fa6dd9 ("dmaengine: Add consumer for the new DMA_MEMCPY_SG API function.")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/20220606074733.622616-1-hch@lst.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>

2 files changed, 0 insertions, 129 deletions

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index e80feeea0e01..c741b6431958 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -1153,13 +1153,6 @@ int dma_async_device_register(struct dma_device *device)
 		return -EIO;
 	}
 
-	if (dma_has_cap(DMA_MEMCPY_SG, device->cap_mask) && !device->device_prep_dma_memcpy_sg) {
-		dev_err(device->dev,
-			"Device claims capability %s, but op is not defined\n",
-			"DMA_MEMCPY_SG");
-		return -EIO;
-	}
-
 	if (dma_has_cap(DMA_XOR, device->cap_mask) && !device->device_prep_dma_xor) {
 		dev_err(device->dev,
 			"Device claims capability %s, but op is not defined\n",
diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index cd62bbb50e8b..6276934d4d2b 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -2128,126 +2128,6 @@ error:
 }
 
 /**
- * xilinx_cdma_prep_memcpy_sg - prepare descriptors for a memcpy_sg transaction
- * @dchan: DMA channel
- * @dst_sg: Destination scatter list
- * @dst_sg_len: Number of entries in destination scatter list
- * @src_sg: Source scatter list
- * @src_sg_len: Number of entries in source scatter list
- * @flags: transfer ack flags
- *
- * Return: Async transaction descriptor on success and NULL on failure
- */
-static struct dma_async_tx_descriptor *xilinx_cdma_prep_memcpy_sg(
-			struct dma_chan *dchan, struct scatterlist *dst_sg,
-			unsigned int dst_sg_len, struct scatterlist *src_sg,
-			unsigned int src_sg_len, unsigned long flags)
-{
-	struct xilinx_dma_chan *chan = to_xilinx_chan(dchan);
-	struct xilinx_dma_tx_descriptor *desc;
-	struct xilinx_cdma_tx_segment *segment, *prev = NULL;
-	struct xilinx_cdma_desc_hw *hw;
-	size_t len, dst_avail, src_avail;
-	dma_addr_t dma_dst, dma_src;
-
-	if (unlikely(dst_sg_len == 0 || src_sg_len == 0))
-		return NULL;
-
-	if (unlikely(!dst_sg  || !src_sg))
-		return NULL;
-
-	desc = xilinx_dma_alloc_tx_descriptor(chan);
-	if (!desc)
-		return NULL;
-
-	dma_async_tx_descriptor_init(&desc->async_tx, &chan->common);
-	desc->async_tx.tx_submit = xilinx_dma_tx_submit;
-
-	dst_avail = sg_dma_len(dst_sg);
-	src_avail = sg_dma_len(src_sg);
-	/*
-	 * loop until there is either no more source or no more destination
-	 * scatterlist entry
-	 */
-	while (true) {
-		len = min_t(size_t, src_avail, dst_avail);
-		len = min_t(size_t, len, chan->xdev->max_buffer_len);
-		if (len == 0)
-			goto fetch;
-
-		/* Allocate the link descriptor from DMA pool */
-		segment = xilinx_cdma_alloc_tx_segment(chan);
-		if (!segment)
-			goto error;
-
-		dma_dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) -
-			dst_avail;
-		dma_src = sg_dma_address(src_sg) + sg_dma_len(src_sg) -
-			src_avail;
-		hw = &segment->hw;
-		hw->control = len;
-		hw->src_addr = dma_src;
-		hw->dest_addr = dma_dst;
-		if (chan->ext_addr) {
-			hw->src_addr_msb = upper_32_bits(dma_src);
-			hw->dest_addr_msb = upper_32_bits(dma_dst);
-		}
-
-		if (prev) {
-			prev->hw.next_desc = segment->phys;
-			if (chan->ext_addr)
-				prev->hw.next_desc_msb =
-					upper_32_bits(segment->phys);
-		}
-
-		prev = segment;
-		dst_avail -= len;
-		src_avail -= len;
-		list_add_tail(&segment->node, &desc->segments);
-
-fetch:
-		/* Fetch the next dst scatterlist entry */
-		if (dst_avail == 0) {
-			if (dst_sg_len == 0)
-				break;
-			dst_sg = sg_next(dst_sg);
-			if (dst_sg == NULL)
-				break;
-			dst_sg_len--;
-			dst_avail = sg_dma_len(dst_sg);
-		}
-		/* Fetch the next src scatterlist entry */
-		if (src_avail == 0) {
-			if (src_sg_len == 0)
-				break;
-			src_sg = sg_next(src_sg);
-			if (src_sg == NULL)
-				break;
-			src_sg_len--;
-			src_avail = sg_dma_len(src_sg);
-		}
-	}
-
-	if (list_empty(&desc->segments)) {
-		dev_err(chan->xdev->dev,
-			"%s: Zero-size SG transfer requested\n", __func__);
-		goto error;
-	}
-
-	/* Link the last hardware descriptor with the first. */
-	segment = list_first_entry(&desc->segments,
-				struct xilinx_cdma_tx_segment, node);
-	desc->async_tx.phys = segment->phys;
-	prev->hw.next_desc = segment->phys;
-
-	return &desc->async_tx;
-
-error:
-	xilinx_dma_free_tx_descriptor(chan, desc);
-	return NULL;
-}
-
-/**
  * xilinx_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction
  * @dchan: DMA channel
  * @sgl: scatterlist to transfer to/from
@@ -3240,9 +3120,7 @@ static int xilinx_dma_probe(struct platform_device *pdev)
 					  DMA_RESIDUE_GRANULARITY_SEGMENT;
 	} else if (xdev->dma_config->dmatype == XDMA_TYPE_CDMA) {
 		dma_cap_set(DMA_MEMCPY, xdev->common.cap_mask);
-		dma_cap_set(DMA_MEMCPY_SG, xdev->common.cap_mask);
 		xdev->common.device_prep_dma_memcpy = xilinx_cdma_prep_memcpy;
-		xdev->common.device_prep_dma_memcpy_sg = xilinx_cdma_prep_memcpy_sg;
 		/* Residue calculation is supported by only AXI DMA and CDMA */
 		xdev->common.residue_granularity =
 					  DMA_RESIDUE_GRANULARITY_SEGMENT;