Commit d4cb37e7 authored by Boris Brezillon's avatar Boris Brezillon
Browse files

mtd: nand: Remove support for block locking/unlocking 



Commit 7d70f334 ("mtd: nand: add lock/unlock routines") introduced
support for the Micron LOCK/UNLOCK commands but no one ever used the
nand_lock/unlock() functions.

Remove support for these vendor-specific operations from the core. If
one ever wants to add them back they should be put in nand_micron.c and
mtd->_lock/_unlock should be directly assigned from there instead of
exporting the functions.

Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
parent 5771a8c0

drivers/mtd/nand/nand_base.c

+0 −173
Original line number Diff line number Diff line
@@ -1239,179 +1239,6 @@ int nand_reset(struct nand_chip *chip, int chipnr) 
	return 0;

}



/**

 * __nand_unlock - [REPLACEABLE] unlocks specified locked blocks

 * @mtd: mtd info

 * @ofs: offset to start unlock from

 * @len: length to unlock

 * @invert:

 *        - when = 0, unlock the range of blocks within the lower and

 *                    upper boundary address

 *        - when = 1, unlock the range of blocks outside the boundaries

 *                    of the lower and upper boundary address

 *

 * Returs unlock status.

 */

static int __nand_unlock(struct mtd_info *mtd, loff_t ofs,

					uint64_t len, int invert)

{

	int ret = 0;

	int status, page;

	struct nand_chip *chip = mtd_to_nand(mtd);



	/* Submit address of first page to unlock */

	page = ofs >> chip->page_shift;

	chip->cmdfunc(mtd, NAND_CMD_UNLOCK1, -1, page & chip->pagemask);



	/* Submit address of last page to unlock */

	page = (ofs + len) >> chip->page_shift;

	chip->cmdfunc(mtd, NAND_CMD_UNLOCK2, -1,

				(page | invert) & chip->pagemask);



	/* Call wait ready function */

	status = chip->waitfunc(mtd, chip);

	/* See if device thinks it succeeded */

	if (status & NAND_STATUS_FAIL) {

		pr_debug("%s: error status = 0x%08x\n",

					__func__, status);

		ret = -EIO;

	}



	return ret;

}



/**

 * nand_unlock - [REPLACEABLE] unlocks specified locked blocks

 * @mtd: mtd info

 * @ofs: offset to start unlock from

 * @len: length to unlock

 *

 * Returns unlock status.

 */

int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)

{

	int ret = 0;

	int chipnr;

	struct nand_chip *chip = mtd_to_nand(mtd);



	pr_debug("%s: start = 0x%012llx, len = %llu\n",

			__func__, (unsigned long long)ofs, len);



	if (check_offs_len(mtd, ofs, len))

		return -EINVAL;



	/* Align to last block address if size addresses end of the device */

	if (ofs + len == mtd->size)

		len -= mtd->erasesize;



	nand_get_device(mtd, FL_UNLOCKING);



	/* Shift to get chip number */

	chipnr = ofs >> chip->chip_shift;



	/*

	 * Reset the chip.

	 * If we want to check the WP through READ STATUS and check the bit 7

	 * we must reset the chip

	 * some operation can also clear the bit 7 of status register

	 * eg. erase/program a locked block

	 */

	nand_reset(chip, chipnr);



	chip->select_chip(mtd, chipnr);



	/* Check, if it is write protected */

	if (nand_check_wp(mtd)) {

		pr_debug("%s: device is write protected!\n",

					__func__);

		ret = -EIO;

		goto out;

	}



	ret = __nand_unlock(mtd, ofs, len, 0);



out:

	chip->select_chip(mtd, -1);

	nand_release_device(mtd);



	return ret;

}

EXPORT_SYMBOL(nand_unlock);



/**

 * nand_lock - [REPLACEABLE] locks all blocks present in the device

 * @mtd: mtd info

 * @ofs: offset to start unlock from

 * @len: length to unlock

 *

 * This feature is not supported in many NAND parts. 'Micron' NAND parts do

 * have this feature, but it allows only to lock all blocks, not for specified

 * range for block. Implementing 'lock' feature by making use of 'unlock', for

 * now.

 *

 * Returns lock status.

 */

int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)

{

	int ret = 0;

	int chipnr, status, page;

	struct nand_chip *chip = mtd_to_nand(mtd);



	pr_debug("%s: start = 0x%012llx, len = %llu\n",

			__func__, (unsigned long long)ofs, len);



	if (check_offs_len(mtd, ofs, len))

		return -EINVAL;



	nand_get_device(mtd, FL_LOCKING);



	/* Shift to get chip number */

	chipnr = ofs >> chip->chip_shift;



	/*

	 * Reset the chip.

	 * If we want to check the WP through READ STATUS and check the bit 7

	 * we must reset the chip

	 * some operation can also clear the bit 7 of status register

	 * eg. erase/program a locked block

	 */

	nand_reset(chip, chipnr);



	chip->select_chip(mtd, chipnr);



	/* Check, if it is write protected */

	if (nand_check_wp(mtd)) {

		pr_debug("%s: device is write protected!\n",

					__func__);

		status = MTD_ERASE_FAILED;

		ret = -EIO;

		goto out;

	}



	/* Submit address of first page to lock */

	page = ofs >> chip->page_shift;

	chip->cmdfunc(mtd, NAND_CMD_LOCK, -1, page & chip->pagemask);



	/* Call wait ready function */

	status = chip->waitfunc(mtd, chip);

	/* See if device thinks it succeeded */

	if (status & NAND_STATUS_FAIL) {

		pr_debug("%s: error status = 0x%08x\n",

					__func__, status);

		ret = -EIO;

		goto out;

	}



	ret = __nand_unlock(mtd, ofs, len, 0x1);



out:

	chip->select_chip(mtd, -1);

	nand_release_device(mtd);



	return ret;

}

EXPORT_SYMBOL(nand_lock);



/**

 * nand_check_erased_buf - check if a buffer contains (almost) only 0xff data

 * @buf: buffer to test

include/linux/mtd/nand.h

+0 −10
Original line number Diff line number Diff line
@@ -44,12 +44,6 @@ void nand_release(struct mtd_info *mtd); 
/* Internal helper for board drivers which need to override command function */

void nand_wait_ready(struct mtd_info *mtd);



/* locks all blocks present in the device */

int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);



/* unlocks specified locked blocks */

int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);



/* The maximum number of NAND chips in an array */

#define NAND_MAX_CHIPS		8
@@ -89,10 +83,6 @@ int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len); 
#define NAND_CMD_SET_FEATURES	0xef

#define NAND_CMD_RESET		0xff



#define NAND_CMD_LOCK		0x2a

#define NAND_CMD_UNLOCK1	0x23

#define NAND_CMD_UNLOCK2	0x24



/* Extended commands for large page devices */

#define NAND_CMD_READSTART	0x30

#define NAND_CMD_RNDOUTSTART	0xE0

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