mtd: onenand: omap2: Unify OMAP2 and OMAP3 DMA implementation

Since the very first commit (36cd4fb5: "[MTD] [OneNAND] Add
OMAP2 / OMAP3 OneNAND driver") DMA is disabled for OMAP2. Later
fixes thus went only into OMAP3 specific DMA functions which
turned out not to be so OMAP3 specific, so merge those two
implementations.
Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Acked-by: Roger Quadros <rogerq@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/onenand/omap2.c

@@ -315,9 +315,7 @@ static inline int omap2_onenand_dma_transfer(struct omap2_onenand *c,
 	return 0;
 }
 
-#if defined(CONFIG_ARCH_OMAP3) || defined(MULTI_OMAP2)
-
-static int omap3_onenand_read_bufferram(struct mtd_info *mtd, int area,
+static int omap2_onenand_read_bufferram(struct mtd_info *mtd, int area,
 					unsigned char *buffer, int offset,
 					size_t count)
 {
@@ -379,7 +377,7 @@ static int omap3_onenand_read_bufferram(struct mtd_info *mtd, int area,
 	return 0;
 }
 
-static int omap3_onenand_write_bufferram(struct mtd_info *mtd, int area,
+static int omap2_onenand_write_bufferram(struct mtd_info *mtd, int area,
 					 const unsigned char *buffer,
 					 int offset, size_t count)
 {
@@ -434,120 +432,6 @@ static int omap3_onenand_write_bufferram(struct mtd_info *mtd, int area,
 	return 0;
 }
 
-#else
-
-static int omap3_onenand_read_bufferram(struct mtd_info *mtd, int area,
-					unsigned char *buffer, int offset,
-					size_t count)
-{
-	return -ENOSYS;
-}
-
-static int omap3_onenand_write_bufferram(struct mtd_info *mtd, int area,
-					 const unsigned char *buffer,
-					 int offset, size_t count)
-{
-	return -ENOSYS;
-}
-
-#endif
-
-#if defined(CONFIG_ARCH_OMAP2) || defined(MULTI_OMAP2)
-
-static int omap2_onenand_read_bufferram(struct mtd_info *mtd, int area,
-					unsigned char *buffer, int offset,
-					size_t count)
-{
-	struct omap2_onenand *c = container_of(mtd, struct omap2_onenand, mtd);
-	struct onenand_chip *this = mtd->priv;
-	dma_addr_t dma_src, dma_dst;
-	int bram_offset, ret;
-
-	bram_offset = omap2_onenand_bufferram_offset(mtd, area) + area + offset;
-	/* DMA is not used.  Revisit PM requirements before enabling it. */
-	if (1 || (c->dma_channel < 0) ||
-	    ((void *) buffer >= (void *) high_memory) || (bram_offset & 3) ||
-	    (((unsigned int) buffer) & 3) || (count < 1024) || (count & 3)) {
-		memcpy(buffer, (__force void *)(this->base + bram_offset),
-		       count);
-		return 0;
-	}
-
-	dma_src = c->phys_base + bram_offset;
-	dma_dst = dma_map_single(&c->pdev->dev, buffer, count,
-				 DMA_FROM_DEVICE);
-	if (dma_mapping_error(&c->pdev->dev, dma_dst)) {
-		dev_err(&c->pdev->dev,
-			"Couldn't DMA map a %d byte buffer\n",
-			count);
-		return -1;
-	}
-
-	ret = omap2_onenand_dma_transfer(c, dma_src, dma_dst, count);
-	dma_unmap_single(&c->pdev->dev, dma_dst, count, DMA_FROM_DEVICE);
-
-	if (ret)
-		dev_err(&c->pdev->dev, "timeout waiting for DMA\n");
-
-	return ret;
-}
-
-static int omap2_onenand_write_bufferram(struct mtd_info *mtd, int area,
-					 const unsigned char *buffer,
-					 int offset, size_t count)
-{
-	struct omap2_onenand *c = container_of(mtd, struct omap2_onenand, mtd);
-	struct onenand_chip *this = mtd->priv;
-	dma_addr_t dma_src, dma_dst;
-	int bram_offset, ret;
-
-	bram_offset = omap2_onenand_bufferram_offset(mtd, area) + area + offset;
-	/* DMA is not used.  Revisit PM requirements before enabling it. */
-	if (1 || (c->dma_channel < 0) ||
-	    ((void *) buffer >= (void *) high_memory) || (bram_offset & 3) ||
-	    (((unsigned int) buffer) & 3) || (count < 1024) || (count & 3)) {
-		memcpy((__force void *)(this->base + bram_offset), buffer,
-		       count);
-		return 0;
-	}
-
-	dma_src = dma_map_single(&c->pdev->dev, (void *) buffer, count,
-				 DMA_TO_DEVICE);
-	dma_dst = c->phys_base + bram_offset;
-	if (dma_mapping_error(&c->pdev->dev, dma_src)) {
-		dev_err(&c->pdev->dev,
-			"Couldn't DMA map a %d byte buffer\n",
-			count);
-		return -1;
-	}
-
-	ret = omap2_onenand_dma_transfer(c, dma_src, dma_dst, count);
-	dma_unmap_single(&c->pdev->dev, dma_src, count, DMA_TO_DEVICE);
-
-	if (ret)
-		dev_err(&c->pdev->dev, "timeout waiting for DMA\n");
-
-	return ret;
-}
-
-#else
-
-static int omap2_onenand_read_bufferram(struct mtd_info *mtd, int area,
-					unsigned char *buffer, int offset,
-					size_t count)
-{
-	return -ENOSYS;
-}
-
-static int omap2_onenand_write_bufferram(struct mtd_info *mtd, int area,
-					 const unsigned char *buffer,
-					 int offset, size_t count)
-{
-	return -ENOSYS;
-}
-
-#endif
-
 static struct platform_driver omap2_onenand_driver;
 
 static void omap2_onenand_shutdown(struct platform_device *pdev)
@@ -671,13 +555,8 @@ static int omap2_onenand_probe(struct platform_device *pdev)
 	this = &c->onenand;
 	if (c->dma_channel >= 0) {
 		this->wait = omap2_onenand_wait;
-		if (c->flags & ONENAND_IN_OMAP34XX) {
-			this->read_bufferram = omap3_onenand_read_bufferram;
-			this->write_bufferram = omap3_onenand_write_bufferram;
-		} else {
-			this->read_bufferram = omap2_onenand_read_bufferram;
-			this->write_bufferram = omap2_onenand_write_bufferram;
-		}
+		this->read_bufferram = omap2_onenand_read_bufferram;
+		this->write_bufferram = omap2_onenand_write_bufferram;
 	}
 
 	if ((r = onenand_scan(&c->mtd, 1)) < 0)