Commit 187ef152 authored by Håvard Skinnemoen's avatar Håvard Skinnemoen Committed by David Woodhouse
Browse files

[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: default avatarHåvard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarDavid Woodhouse <dwmw2@infradead.org>
parent e478bec0

drivers/mtd/chips/cfi_cmdset_0002.c

+1 −0
Original line number Diff line number Diff line
@@ -212,6 +212,7 @@ static void fixup_use_atmel_lock(struct mtd_info *mtd, void *param) 
{

	mtd->lock = cfi_atmel_lock;

	mtd->unlock = cfi_atmel_unlock;

	mtd->flags |= MTD_STUPID_LOCK;

}



static struct cfi_fixup cfi_fixup_table[] = {

drivers/mtd/mtdcore.c

+10 −0
Original line number Diff line number Diff line
@@ -57,6 +57,16 @@ int add_mtd_device(struct mtd_info *mtd) 
			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 */

include/mtd/mtd-abi.h

+1 −0
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ struct mtd_oob_buf { 
#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

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