diff options
| -rw-r--r-- | drivers/mtd/maps/sa1100-flash.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/mtd/maps/sa1100-flash.c b/drivers/mtd/maps/sa1100-flash.c index cbc3b786791..1eaf7b6c35e 100644 --- a/drivers/mtd/maps/sa1100-flash.c +++ b/drivers/mtd/maps/sa1100-flash.c @@ -36,10 +36,22 @@ struct sa_info { struct sa_subdev_info subdev[0]; }; +static DEFINE_SPINLOCK(sa1100_vpp_lock); +static int sa1100_vpp_refcnt; static void sa1100_set_vpp(struct map_info *map, int on) { struct sa_subdev_info *subdev = container_of(map, struct sa_subdev_info, map); - subdev->plat->set_vpp(on); + unsigned long flags; + + spin_lock_irqsave(&sa1100_vpp_lock, flags); + if (on) { + if (++sa1100_vpp_refcnt == 1) /* first nested 'on' */ + subdev->plat->set_vpp(1); + } else { + if (--sa1100_vpp_refcnt == 0) /* last nested 'off' */ + subdev->plat->set_vpp(0); + } + spin_unlock_irqrestore(&sa1100_vpp_lock, flags); } static void sa1100_destroy_subdev(struct sa_subdev_info *subdev) |