mtd: maps: physmap: 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 physmap_set_vpp() calls to be nested by adding a reference
counter.
omap1_set_vpp() already used a reference counter. Since it is called from
physmap_set_vpp(), omap1_set_vpp() can now be simplified.
simtec_nor_vpp() already disabled hard interrupts. Since it is called from
physmap_set_vpp(), simtec_nor_vpp() can now be simplified.
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>
diff --git a/drivers/mtd/maps/physmap.c b/drivers/mtd/maps/physmap.c
index abc5626..7e9233c 100644
--- a/drivers/mtd/maps/physmap.c
+++ b/drivers/mtd/maps/physmap.c
@@ -27,6 +27,8 @@
struct mtd_info *mtd[MAX_RESOURCES];
struct mtd_info *cmtd;
struct map_info map[MAX_RESOURCES];
+ spinlock_t vpp_lock;
+ int vpp_refcnt;
};
static int physmap_flash_remove(struct platform_device *dev)
@@ -63,12 +65,26 @@
{
struct platform_device *pdev;
struct physmap_flash_data *physmap_data;
+ struct physmap_flash_info *info;
+ unsigned long flags;
pdev = (struct platform_device *)map->map_priv_1;
physmap_data = pdev->dev.platform_data;
- if (physmap_data->set_vpp)
- physmap_data->set_vpp(pdev, state);
+ if (!physmap_data->set_vpp)
+ return;
+
+ info = platform_get_drvdata(pdev);
+
+ spin_lock_irqsave(&info->vpp_lock, flags);
+ if (state) {
+ if (++info->vpp_refcnt == 1) /* first nested 'on' */
+ physmap_data->set_vpp(pdev, 1);
+ } else {
+ if (--info->vpp_refcnt == 0) /* last nested 'off' */
+ physmap_data->set_vpp(pdev, 0);
+ }
+ spin_unlock_irqrestore(&info->vpp_lock, flags);
}
static const char *rom_probe_types[] = {
@@ -172,6 +188,8 @@
if (err)
goto err_out;
+ spin_lock_init(&info->vpp_lock);
+
part_types = physmap_data->part_probe_types ? : part_probe_types;
mtd_device_parse_register(info->cmtd, part_types, 0,