drivers/dma: remove unused support for MEMSET operations

There have never been any real users of MEMSET operations since they
have been introduced in January 2007 by commit 7405f74badf4 ("dmaengine:
refactor dmaengine around dma_async_tx_descriptor").  Therefore remove
support for them for now, it can be always brought back when needed.

[sebastian.hesselbarth@gmail.com: fix drivers/dma/mv_xor]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Acked-by: Dan Williams <djbw@fb.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Olof Johansson <olof@lixom.net>
Cc: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index d64ae14..200f1a3 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -89,11 +89,6 @@
 	hw_desc->phy_next_desc = 0;
 }
 
-static void mv_desc_set_block_fill_val(struct mv_xor_desc_slot *desc, u32 val)
-{
-	desc->value = val;
-}
-
 static void mv_desc_set_dest_addr(struct mv_xor_desc_slot *desc,
 				  dma_addr_t addr)
 {
@@ -128,22 +123,6 @@
 	__raw_writel(next_desc_addr, XOR_NEXT_DESC(chan));
 }
 
-static void mv_chan_set_dest_pointer(struct mv_xor_chan *chan, u32 desc_addr)
-{
-	__raw_writel(desc_addr, XOR_DEST_POINTER(chan));
-}
-
-static void mv_chan_set_block_size(struct mv_xor_chan *chan, u32 block_size)
-{
-	__raw_writel(block_size, XOR_BLOCK_SIZE(chan));
-}
-
-static void mv_chan_set_value(struct mv_xor_chan *chan, u32 value)
-{
-	__raw_writel(value, XOR_INIT_VALUE_LOW(chan));
-	__raw_writel(value, XOR_INIT_VALUE_HIGH(chan));
-}
-
 static void mv_chan_unmask_interrupts(struct mv_xor_chan *chan)
 {
 	u32 val = __raw_readl(XOR_INTR_MASK(chan));
@@ -186,8 +165,6 @@
 
 	if (chain_old_tail->type != desc->type)
 		return 0;
-	if (desc->type == DMA_MEMSET)
-		return 0;
 
 	return 1;
 }
@@ -205,9 +182,6 @@
 	case DMA_MEMCPY:
 		op_mode = XOR_OPERATION_MODE_MEMCPY;
 		break;
-	case DMA_MEMSET:
-		op_mode = XOR_OPERATION_MODE_MEMSET;
-		break;
 	default:
 		dev_err(mv_chan_to_devp(chan),
 			"error: unsupported operation %d\n",
@@ -274,18 +248,9 @@
 	if (sw_desc->type != mv_chan->current_type)
 		mv_set_mode(mv_chan, sw_desc->type);
 
-	if (sw_desc->type == DMA_MEMSET) {
-		/* for memset requests we need to program the engine, no
-		 * descriptors used.
-		 */
-		struct mv_xor_desc *hw_desc = sw_desc->hw_desc;
-		mv_chan_set_dest_pointer(mv_chan, hw_desc->phy_dest_addr);
-		mv_chan_set_block_size(mv_chan, sw_desc->unmap_len);
-		mv_chan_set_value(mv_chan, sw_desc->value);
-	} else {
-		/* set the hardware chain */
-		mv_chan_set_next_descriptor(mv_chan, sw_desc->async_tx.phys);
-	}
+	/* set the hardware chain */
+	mv_chan_set_next_descriptor(mv_chan, sw_desc->async_tx.phys);
+
 	mv_chan->pending += sw_desc->slot_cnt;
 	mv_xor_issue_pending(&mv_chan->dmachan);
 }
@@ -688,43 +653,6 @@
 }
 
 static struct dma_async_tx_descriptor *
-mv_xor_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
-		       size_t len, unsigned long flags)
-{
-	struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
-	struct mv_xor_desc_slot *sw_desc, *grp_start;
-	int slot_cnt;
-
-	dev_dbg(mv_chan_to_devp(mv_chan),
-		"%s dest: %x len: %u flags: %ld\n",
-		__func__, dest, len, flags);
-	if (unlikely(len < MV_XOR_MIN_BYTE_COUNT))
-		return NULL;
-
-	BUG_ON(len > MV_XOR_MAX_BYTE_COUNT);
-
-	spin_lock_bh(&mv_chan->lock);
-	slot_cnt = mv_chan_memset_slot_count(len);
-	sw_desc = mv_xor_alloc_slots(mv_chan, slot_cnt, 1);
-	if (sw_desc) {
-		sw_desc->type = DMA_MEMSET;
-		sw_desc->async_tx.flags = flags;
-		grp_start = sw_desc->group_head;
-		mv_desc_init(grp_start, flags);
-		mv_desc_set_byte_count(grp_start, len);
-		mv_desc_set_dest_addr(sw_desc->group_head, dest);
-		mv_desc_set_block_fill_val(grp_start, value);
-		sw_desc->unmap_src_cnt = 1;
-		sw_desc->unmap_len = len;
-	}
-	spin_unlock_bh(&mv_chan->lock);
-	dev_dbg(mv_chan_to_devp(mv_chan),
-		"%s sw_desc %p async_tx %p \n",
-		__func__, sw_desc, &sw_desc->async_tx);
-	return sw_desc ? &sw_desc->async_tx : NULL;
-}
-
-static struct dma_async_tx_descriptor *
 mv_xor_prep_dma_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
 		    unsigned int src_cnt, size_t len, unsigned long flags)
 {
@@ -1137,8 +1065,6 @@
 	/* set prep routines based on capability */
 	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask))
 		dma_dev->device_prep_dma_memcpy = mv_xor_prep_dma_memcpy;
-	if (dma_has_cap(DMA_MEMSET, dma_dev->cap_mask))
-		dma_dev->device_prep_dma_memset = mv_xor_prep_dma_memset;
 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
 		dma_dev->max_xor = 8;
 		dma_dev->device_prep_dma_xor = mv_xor_prep_dma_xor;
@@ -1187,9 +1113,8 @@
 			goto err_free_irq;
 	}
 
-	dev_info(&pdev->dev, "Marvell XOR: ( %s%s%s%s)\n",
+	dev_info(&pdev->dev, "Marvell XOR: ( %s%s%s)\n",
 		 dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "",
-		 dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)  ? "fill " : "",
 		 dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "cpy " : "",
 		 dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask) ? "intr " : "");
 
@@ -1298,8 +1223,6 @@
 				dma_cap_set(DMA_MEMCPY, cap_mask);
 			if (of_property_read_bool(np, "dmacap,xor"))
 				dma_cap_set(DMA_XOR, cap_mask);
-			if (of_property_read_bool(np, "dmacap,memset"))
-				dma_cap_set(DMA_MEMSET, cap_mask);
 			if (of_property_read_bool(np, "dmacap,interrupt"))
 				dma_cap_set(DMA_INTERRUPT, cap_mask);