dmaengine: remove DMA_SG as it is dead code in kernel

There are no in kernel consumers for DMA_SG op. Removing operation,
dead code, and test code in dmatest.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Gary Hook <gary.hook@amd.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Kedareswara rao Appana <appana.durga.rao@xilinx.com>
Cc: Li Yang <leoyang.li@nxp.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 1 insertions, 139 deletions

diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 1baf3404a365..fbab271b3bf9 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -1203,138 +1203,6 @@ err:
 }
 
 /**
- * atc_prep_dma_sg - prepare memory to memory scather-gather operation
- * @chan: the channel to prepare operation on
- * @dst_sg: destination scatterlist
- * @dst_nents: number of destination scatterlist entries
- * @src_sg: source scatterlist
- * @src_nents: number of source scatterlist entries
- * @flags: tx descriptor status flags
- */
-static struct dma_async_tx_descriptor *
-atc_prep_dma_sg(struct dma_chan *chan,
-		struct scatterlist *dst_sg, unsigned int dst_nents,
-		struct scatterlist *src_sg, unsigned int src_nents,
-		unsigned long flags)
-{
-	struct at_dma_chan	*atchan = to_at_dma_chan(chan);
-	struct at_desc		*desc = NULL;
-	struct at_desc		*first = NULL;
-	struct at_desc		*prev = NULL;
-	unsigned int		src_width;
-	unsigned int		dst_width;
-	size_t			xfer_count;
-	u32			ctrla;
-	u32			ctrlb;
-	size_t			dst_len = 0, src_len = 0;
-	dma_addr_t		dst = 0, src = 0;
-	size_t			len = 0, total_len = 0;
-
-	if (unlikely(dst_nents == 0 || src_nents == 0))
-		return NULL;
-
-	if (unlikely(dst_sg == NULL || src_sg == NULL))
-		return NULL;
-
-	ctrlb =   ATC_DEFAULT_CTRLB | ATC_IEN
-		| ATC_SRC_ADDR_MODE_INCR
-		| ATC_DST_ADDR_MODE_INCR
-		| ATC_FC_MEM2MEM;
-
-	/*
-	 * loop until there is either no more source or no more destination
-	 * scatterlist entry
-	 */
-	while (true) {
-
-		/* prepare the next transfer */
-		if (dst_len == 0) {
-
-			/* no more destination scatterlist entries */
-			if (!dst_sg || !dst_nents)
-				break;
-
-			dst = sg_dma_address(dst_sg);
-			dst_len = sg_dma_len(dst_sg);
-
-			dst_sg = sg_next(dst_sg);
-			dst_nents--;
-		}
-
-		if (src_len == 0) {
-
-			/* no more source scatterlist entries */
-			if (!src_sg || !src_nents)
-				break;
-
-			src = sg_dma_address(src_sg);
-			src_len = sg_dma_len(src_sg);
-
-			src_sg = sg_next(src_sg);
-			src_nents--;
-		}
-
-		len = min_t(size_t, src_len, dst_len);
-		if (len == 0)
-			continue;
-
-		/* take care for the alignment */
-		src_width = dst_width = atc_get_xfer_width(src, dst, len);
-
-		ctrla = ATC_SRC_WIDTH(src_width) |
-			ATC_DST_WIDTH(dst_width);
-
-		/*
-		 * The number of transfers to set up refer to the source width
-		 * that depends on the alignment.
-		 */
-		xfer_count = len >> src_width;
-		if (xfer_count > ATC_BTSIZE_MAX) {
-			xfer_count = ATC_BTSIZE_MAX;
-			len = ATC_BTSIZE_MAX << src_width;
-		}
-
-		/* create the transfer */
-		desc = atc_desc_get(atchan);
-		if (!desc)
-			goto err_desc_get;
-
-		desc->lli.saddr = src;
-		desc->lli.daddr = dst;
-		desc->lli.ctrla = ctrla | xfer_count;
-		desc->lli.ctrlb = ctrlb;
-
-		desc->txd.cookie = 0;
-		desc->len = len;
-
-		atc_desc_chain(&first, &prev, desc);
-
-		/* update the lengths and addresses for the next loop cycle */
-		dst_len -= len;
-		src_len -= len;
-		dst += len;
-		src += len;
-
-		total_len += len;
-	}
-
-	/* First descriptor of the chain embedds additional information */
-	first->txd.cookie = -EBUSY;
-	first->total_len = total_len;
-
-	/* set end-of-link to the last link descriptor of list*/
-	set_desc_eol(desc);
-
-	first->txd.flags = flags; /* client is in control of this ack */
-
-	return &first->txd;
-
-err_desc_get:
-	atc_desc_put(atchan, first);
-	return NULL;
-}
-
-/**
  * atc_dma_cyclic_check_values
  * Check for too big/unaligned periods and unaligned DMA buffer
  */
@@ -1933,14 +1801,12 @@ static int __init at_dma_probe(struct platform_device *pdev)
 
 	/* setup platform data for each SoC */
 	dma_cap_set(DMA_MEMCPY, at91sam9rl_config.cap_mask);
-	dma_cap_set(DMA_SG, at91sam9rl_config.cap_mask);
 	dma_cap_set(DMA_INTERLEAVE, at91sam9g45_config.cap_mask);
 	dma_cap_set(DMA_MEMCPY, at91sam9g45_config.cap_mask);
 	dma_cap_set(DMA_MEMSET, at91sam9g45_config.cap_mask);
 	dma_cap_set(DMA_MEMSET_SG, at91sam9g45_config.cap_mask);
 	dma_cap_set(DMA_PRIVATE, at91sam9g45_config.cap_mask);
 	dma_cap_set(DMA_SLAVE, at91sam9g45_config.cap_mask);
-	dma_cap_set(DMA_SG, at91sam9g45_config.cap_mask);
 
 	/* get DMA parameters from controller type */
 	plat_dat = at_dma_get_driver_data(pdev);
@@ -2078,16 +1944,12 @@ static int __init at_dma_probe(struct platform_device *pdev)
 		atdma->dma_common.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 	}
 
-	if (dma_has_cap(DMA_SG, atdma->dma_common.cap_mask))
-		atdma->dma_common.device_prep_dma_sg = atc_prep_dma_sg;
-
 	dma_writel(atdma, EN, AT_DMA_ENABLE);
 
-	dev_info(&pdev->dev, "Atmel AHB DMA Controller ( %s%s%s%s), %d channels\n",
+	dev_info(&pdev->dev, "Atmel AHB DMA Controller ( %s%s%s), %d channels\n",
 	  dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask) ? "cpy " : "",
 	  dma_has_cap(DMA_MEMSET, atdma->dma_common.cap_mask) ? "set " : "",
 	  dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask)  ? "slave " : "",
-	  dma_has_cap(DMA_SG, atdma->dma_common.cap_mask)  ? "sg-cpy " : "",
 	  plat_dat->nr_channels);
 
 	dma_async_device_register(&atdma->dma_common);