1 files changed, 12 insertions, 20 deletions

diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index 6fae04b3fc6d..950646aa4c4b 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -209,22 +209,8 @@ static int atmel_nand_dma_op(struct mtd_info *mtd, void *buf, int len,
         int err = -EIO;
         enum dma_data_direction dir = is_read ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
 
-        if (buf >= high_memory) {
-                struct page *pg;
-
-                if (((size_t)buf & PAGE_MASK) !=
-                    ((size_t)(buf + len - 1) & PAGE_MASK)) {
-                        dev_warn(host->dev, "Buffer not fit in one page\n");
-                        goto err_buf;
-                }
-
-                pg = vmalloc_to_page(buf);
-                if (pg == 0) {
-                        dev_err(host->dev, "Failed to vmalloc_to_page\n");
-                        goto err_buf;
-                }
-                p = page_address(pg) + ((size_t)buf & ~PAGE_MASK);
-        }
+        if (buf >= high_memory)
+                goto err_buf;
 
         dma_dev = host->dma_chan->device;
 
@@ -280,7 +266,8 @@ static void atmel_read_buf(struct mtd_info *mtd, u8 *buf, int len)
         struct nand_chip *chip = mtd->priv;
         struct atmel_nand_host *host = chip->priv;
 
-        if (use_dma && len >= mtd->oobsize)
+        if (use_dma && len > mtd->oobsize)
+                /* only use DMA for bigger than oob size: better performances */
                 if (atmel_nand_dma_op(mtd, buf, len, 1) == 0)
                         return;
 
@@ -295,7 +282,8 @@ static void atmel_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
         struct nand_chip *chip = mtd->priv;
         struct atmel_nand_host *host = chip->priv;
 
-        if (use_dma && len >= mtd->oobsize)
+        if (use_dma && len > mtd->oobsize)
+                /* only use DMA for bigger than oob size: better performances */
                 if (atmel_nand_dma_op(mtd, (void *)buf, len, 0) == 0)
                         return;
 
@@ -599,7 +587,10 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
                 nand_chip->options |= NAND_USE_FLASH_BBT;
         }
 
-        if (cpu_has_dma() && use_dma) {
+        if (!cpu_has_dma())
+                use_dma = 0;
+
+        if (use_dma) {
                 dma_cap_mask_t mask;
 
                 dma_cap_zero(mask);
@@ -611,7 +602,8 @@ static int __init atmel_nand_probe(struct platform_device *pdev)
                 }
         }
         if (use_dma)
-                dev_info(host->dev, "Using DMA for NAND access.\n");
+                dev_info(host->dev, "Using %s for DMA transfers.\n",
+                                        dma_chan_name(host->dma_chan));
         else
                 dev_info(host->dev, "No DMA support for NAND access.\n");