[PATCH 2/2][v5] driver: mtd: update struct map_info's swap as per map requirement

Prabhakar Kushwaha prabhakar.kushwaha at nxp.com
Tue Feb 27 23:33:35 PST 2018

It is not necessary for all device's maps to be CFI_HOST_ENDIAN.
Maps device can be Big endian or little endian.

Currently it is being taken care using CONFIG_MTD_CFI_LE_BYTE_SWAP or
CONFIG_MTD_CFI_BE_BYTE_SWAP i.e. compile time.

Now update struct map_info's swap field based on device characteristics
defined in device tree.

Signed-off-by: Jagdish Gediya <jagdish.gediya at nxp.com>
Signed-off-by: Prabhakar Kushwaha <prabhakar.kushwaha at nxp.com>
Changes for v2: Incorporated review comments from Boris Brezillon
Changes for v3: None
Changes for v4: Updated code as per new defined binding of physmap.txt
Changes for v5: Avoid map.swap set in case of endiannes not defined in dts file

 drivers/mtd/maps/physmap_of_core.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/mtd/maps/physmap_of_core.c b/drivers/mtd/maps/physmap_of_core.c
index b1bd4faecfb2..527b1682381f 100644
--- a/drivers/mtd/maps/physmap_of_core.c
+++ b/drivers/mtd/maps/physmap_of_core.c
@@ -20,6 +20,7 @@
 #include <linux/mtd/map.h>
 #include <linux/mtd/partitions.h>
 #include <linux/mtd/concat.h>
+#include <linux/mtd/cfi_endian.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
@@ -233,6 +234,11 @@ static int of_flash_probe(struct platform_device *dev)
 		info->list[i].map.bankwidth = be32_to_cpup(width);
 		info->list[i].map.device_node = dp;
+		if (of_property_read_bool(dp, "big-endian"))
+			info->list[i].map.swap = CFI_BIG_ENDIAN;
+		else if (of_property_read_bool(dp, "little-endian"))
+			info->list[i].map.swap = CFI_LITTLE_ENDIAN;
 		err = of_flash_probe_gemini(dev, dp, &info->list[i].map);
 		if (err)
 			goto err_out;

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