mtd: return error code from mtd_unpoint

The 'mtd_unpoint()' API function should be able to return an error code because
it may fail if you specify incorrect offset. This patch changes this MTD API
function and amends all the drivers correspondingly.

Also return '-EOPNOTSUPP' from 'mtd_unpoint()' when the '->unpoint()' method is
undefined. We do not really need this currently, but this just makes
sense to be consistent with 'mtd_point()'.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 8 insertions, 4 deletions

diff --git a/drivers/mtd/lpddr/lpddr_cmds.c b/drivers/mtd/lpddr/lpddr_cmds.c
index fd19d3b1ee90..de960b1d395a 100644
--- a/drivers/mtd/lpddr/lpddr_cmds.c
+++ b/drivers/mtd/lpddr/lpddr_cmds.c
@@ -40,7 +40,7 @@ static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
 static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
                         size_t *retlen, void **mtdbuf, resource_size_t *phys);
-static void lpddr_unpoint(struct mtd_info *mtd, loff_t adr, size_t len);
+static int lpddr_unpoint(struct mtd_info *mtd, loff_t adr, size_t len);
 static int get_chip(struct map_info *map, struct flchip *chip, int mode);
 static int chip_ready(struct map_info *map, struct flchip *chip, int mode);
 static void put_chip(struct map_info *map, struct flchip *chip);
@@ -575,11 +575,11 @@ static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
         return 0;
 }
 
-static void lpddr_unpoint (struct mtd_info *mtd, loff_t adr, size_t len)
+static int lpddr_unpoint (struct mtd_info *mtd, loff_t adr, size_t len)
 {
         struct map_info *map = mtd->priv;
         struct lpddr_private *lpddr = map->fldrv_priv;
-        int chipnum = adr >> lpddr->chipshift;
+        int chipnum = adr >> lpddr->chipshift, err = 0;
         unsigned long ofs;
 
         /* ofs: offset within the first chip that the first read should start */
@@ -603,9 +603,11 @@ static void lpddr_unpoint (struct mtd_info *mtd, loff_t adr, size_t len)
                         chip->ref_point_counter--;
                         if (chip->ref_point_counter == 0)
                                 chip->state = FL_READY;
-                } else
+                } else {
                         printk(KERN_WARNING "%s: Warning: unpoint called on non"
                                         "pointed region\n", map->name);
+                        err = -EINVAL;
+                }
 
                 put_chip(map, chip);
                 mutex_unlock(&chip->mutex);
@@ -614,6 +616,8 @@ static void lpddr_unpoint (struct mtd_info *mtd, loff_t adr, size_t len)
                 ofs = 0;
                 chipnum++;
         }
+
+        return err;
 }
 
 static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to, size_t len,