diff options
| author | Paul Parsons <lost.distance@yahoo.com> | 2012-03-07 14:13:41 +0000 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2012-03-27 00:52:56 +0100 |
| commit | 7c8d206f219fe52966d970f791246a542718e5ba (patch) | |
| tree | 1b9c6e0630aed4df9efb911fccd276c978dd1b23 | |
| parent | 5fbabf3f45a15c2b39170980cee01368138f4d79 (diff) | |
mtd: maps: pcmciamtd: 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 pcmciamtd_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>
| -rw-r--r-- | drivers/mtd/maps/pcmciamtd.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/mtd/maps/pcmciamtd.c b/drivers/mtd/maps/pcmciamtd.c index e8e9fec23553..7d5cf369f0ad 100644 --- a/drivers/mtd/maps/pcmciamtd.c +++ b/drivers/mtd/maps/pcmciamtd.c @@ -295,13 +295,24 @@ static void pcmcia_copy_to(struct map_info *map, unsigned long to, const void *f } +static DEFINE_SPINLOCK(pcmcia_vpp_lock); +static int pcmcia_vpp_refcnt; static void pcmciamtd_set_vpp(struct map_info *map, int on) { struct pcmciamtd_dev *dev = (struct pcmciamtd_dev *)map->map_priv_1; struct pcmcia_device *link = dev->p_dev; + unsigned long flags; pr_debug("dev = %p on = %d vpp = %d\n\n", dev, on, dev->vpp); - pcmcia_fixup_vpp(link, on ? dev->vpp : 0); + spin_lock_irqsave(&pcmcia_vpp_lock, flags); + if (on) { + if (++pcmcia_vpp_refcnt == 1) /* first nested 'on' */ + pcmcia_fixup_vpp(link, dev->vpp); + } else { + if (--pcmcia_vpp_refcnt == 0) /* last nested 'off' */ + pcmcia_fixup_vpp(link, 0); + } + spin_unlock_irqrestore(&pcmcia_vpp_lock, flags); } |