diff options
| author | Paul Parsons <lost.distance@yahoo.com> | 2012-03-07 14:14:31 +0000 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2012-03-27 00:53:02 +0100 |
| commit | ee478af8b675908b217198a75cf759d422a81ccb (patch) | |
| tree | 3f9b3bdb6967607cf7e13579469f0ceaeb0e3bfe /drivers/mtd/maps/sa1100-flash.c | |
| parent | 7c8d206f219fe52966d970f791246a542718e5ba (diff) | |
mtd: maps: sa1100-flash: Add reference counter to set_vpp()
This patch is part of a set which fixes unnecessary flash erase and write errors
resulting from the MTD CFI driver turning off vpp while an erase is in progress.
This patch allows sa1100_set_vpp() calls to be nested by adding a reference
counter.
Signed-off-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/mtd/maps/sa1100-flash.c')
| -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) |