1 files changed, 17 insertions, 0 deletions

diff --git a/drivers/mtd/chips/map_ram.c b/drivers/mtd/chips/map_ram.c
index 072dd8abf33a..6bdc50c727e7 100644
--- a/drivers/mtd/chips/map_ram.c
+++ b/drivers/mtd/chips/map_ram.c
@@ -21,6 +21,8 @@ static int mapram_write (struct mtd_info *, loff_t, size_t, size_t *, const u_ch
 static int mapram_erase (struct mtd_info *, struct erase_info *);
 static void mapram_nop (struct mtd_info *);
 static struct mtd_info *map_ram_probe(struct map_info *map);
+static unsigned long mapram_unmapped_area(struct mtd_info *, unsigned long,
+                                          unsigned long, unsigned long);
 
 
 static struct mtd_chip_driver mapram_chipdrv = {
@@ -64,6 +66,7 @@ static struct mtd_info *map_ram_probe(struct map_info *map)
         mtd->type = MTD_RAM;
         mtd->size = map->size;
         mtd->erase = mapram_erase;
+        mtd->get_unmapped_area = mapram_unmapped_area;
         mtd->read = mapram_read;
         mtd->write = mapram_write;
         mtd->sync = mapram_nop;
@@ -79,6 +82,20 @@ static struct mtd_info *map_ram_probe(struct map_info *map)
 }
 
 
+/*
+ * Allow NOMMU mmap() to directly map the device (if not NULL)
+ * - return the address to which the offset maps
+ * - return -ENOSYS to indicate refusal to do the mapping
+ */
+static unsigned long mapram_unmapped_area(struct mtd_info *mtd,
+                                          unsigned long len,
+                                          unsigned long offset,
+                                          unsigned long flags)
+{
+        struct map_info *map = mtd->priv;
+        return (unsigned long) map->virt + offset;
+}
+
 static int mapram_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
 {
         struct map_info *map = mtd->priv;