mtd: blackfin NFC: fix hang when using NAND on BF527-EZKITs

The DMAs have different bit sizes on BF52x and BF54x.  From the PHRM:

"The 16-bit DMA Access Bus (DAB) connects the DMA controller to the
on-chip peripherals, PPI, SPI, Ethernet MAC, the SPORTs, NFC,
HOSTDP and the UARTs."

32-bit DMA won't work for BF52x.

Signed-off-by: Cliff Cai <cliff.cai@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/drivers/mtd/nand/bf5xx_nand.c b/drivers/mtd/nand/bf5xx_nand.c
index 2ab42d2d4f91..8506e7e606fd 100644
--- a/drivers/mtd/nand/bf5xx_nand.c
+++ b/drivers/mtd/nand/bf5xx_nand.c
@@ -496,11 +496,20 @@ static void bf5xx_nand_dma_rw(struct mtd_info *mtd,
         /* setup DMA register with Blackfin DMA API */
         set_dma_config(CH_NFC, 0x0);
         set_dma_start_addr(CH_NFC, (unsigned long) buf);
+
+/* The DMAs have different size on BF52x and BF54x */
+#ifdef CONFIG_BF52x
+        set_dma_x_count(CH_NFC, (page_size >> 1));
+        set_dma_x_modify(CH_NFC, 2);
+        val = DI_EN | WDSIZE_16;
+#endif
+
+#ifdef CONFIG_BF54x
         set_dma_x_count(CH_NFC, (page_size >> 2));
         set_dma_x_modify(CH_NFC, 4);
-
-        /* setup write or read operation */
         val = DI_EN | WDSIZE_32;
+#endif
+        /* setup write or read operation */
         if (is_read)
                 val |= WNR;
         set_dma_config(CH_NFC, val);