Commit 5fbabf3f authored by Paul Parsons's avatar Paul Parsons Committed by David Woodhouse

mtd: maps: l440gx: 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 l440gx_set_vpp() calls to be nested by adding a reference
counter.
Signed-off-by: default avatarPaul Parsons <lost.distance@yahoo.com>
Signed-off-by: default avatarArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
parent 876fe76d
...@@ -27,17 +27,21 @@ static struct mtd_info *mymtd; ...@@ -27,17 +27,21 @@ static struct mtd_info *mymtd;
/* Is this really the vpp port? */ /* Is this really the vpp port? */
static DEFINE_SPINLOCK(l440gx_vpp_lock);
static int l440gx_vpp_refcnt;
static void l440gx_set_vpp(struct map_info *map, int vpp) static void l440gx_set_vpp(struct map_info *map, int vpp)
{ {
unsigned long l; unsigned long flags;
l = inl(VPP_PORT); spin_lock_irqsave(&l440gx_vpp_lock, flags);
if (vpp) { if (vpp) {
l |= 1; if (++l440gx_vpp_refcnt == 1) /* first nested 'on' */
outl(inl(VPP_PORT) | 1, VPP_PORT);
} else { } else {
l &= ~1; if (--l440gx_vpp_refcnt == 0) /* last nested 'off' */
outl(inl(VPP_PORT) & ~1, VPP_PORT);
} }
outl(l, VPP_PORT); spin_unlock_irqrestore(&l440gx_vpp_lock, flags);
} }
static struct map_info l440gx_map = { static struct map_info l440gx_map = {
......
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