[MTD] Unlock NOR flash automatically where necessary
Introduce the MTD_STUPID_LOCK flag which indicates that the flash chip is
always locked after power-up, so all sectors need to be unlocked before it
is usable.
If this flag is set, and the chip provides an unlock() operation,
mtd_add_device will unlock the whole MTD device if it's writeable. This
means that non-writeable partitions will stay locked.
Set MTD_STUPID_LOCK in fixup_use_atmel_lock() so that these chips will work
as expected.
Signed-off-by: Håvard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index a482e89..702ae4c 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -212,6 +212,7 @@
{
mtd->lock = cfi_atmel_lock;
mtd->unlock = cfi_atmel_unlock;
+ mtd->flags |= MTD_STUPID_LOCK;
}
static struct cfi_fixup cfi_fixup_table[] = {
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 168d3ba..c4d26de 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -57,6 +57,16 @@
mtd->index = i;
mtd->usecount = 0;
+ /* Some chips always power up locked. Unlock them now */
+ if ((mtd->flags & MTD_WRITEABLE)
+ && (mtd->flags & MTD_STUPID_LOCK) && mtd->unlock) {
+ if (mtd->unlock(mtd, 0, mtd->size))
+ printk(KERN_WARNING
+ "%s: unlock failed, "
+ "writes may not work\n",
+ mtd->name);
+ }
+
DEBUG(0, "mtd: Giving out device %d to %s\n",i, mtd->name);
/* No need to get a refcount on the module containing
the notifier, since we hold the mtd_table_mutex */
diff --git a/include/mtd/mtd-abi.h b/include/mtd/mtd-abi.h
index 1da3f7f..b0a67b7 100644
--- a/include/mtd/mtd-abi.h
+++ b/include/mtd/mtd-abi.h
@@ -34,6 +34,7 @@
#define MTD_WRITEABLE 0x400 /* Device is writeable */
#define MTD_BIT_WRITEABLE 0x800 /* Single bits can be flipped */
#define MTD_NO_ERASE 0x1000 /* No erase necessary */
+#define MTD_STUPID_LOCK 0x2000 /* Always locked after reset */
// Some common devices / combinations of capabilities
#define MTD_CAP_ROM 0