Commit 956e944c authored by David Woodhouse's avatar David Woodhouse
Browse files

[MTD NAND] Allow override of page read and write functions. 



- allow high-level nand_write_page() function to be overridden
- likewise low-level write_page_raw() and read_page_raw() functions
- Clean up the abuse of chip->ecc.{write,read}_page() with MTD_OOB_RAW

Signed-off-by: default avatarDavid Woodhouse <dwmw2@infradead.org>
parent 4bf63fcb

drivers/mtd/nand/nand_base.c

+21 −23
Original line number Diff line number Diff line
@@ -990,6 +990,9 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from, 
			}



			/* Now read the page into the buffer */

			if (unlikely(ops->mode == MTD_OOB_RAW))

				ret = chip->ecc.read_page_raw(mtd, chip, bufpoi);

			else

				ret = chip->ecc.read_page(mtd, chip, bufpoi);

			if (ret < 0)

				break;
@@ -1323,8 +1326,6 @@ static int nand_do_read_oob(struct mtd_info *mtd, loff_t from, 
static int nand_read_oob(struct mtd_info *mtd, loff_t from,

			 struct mtd_oob_ops *ops)

{

	int (*read_page)(struct mtd_info *mtd, struct nand_chip *chip,

			 uint8_t *buf) = NULL;

	struct nand_chip *chip = mtd->priv;

	int ret = -ENOTSUPP;
@@ -1342,12 +1343,7 @@ static int nand_read_oob(struct mtd_info *mtd, loff_t from, 
	switch(ops->mode) {

	case MTD_OOB_PLACE:

	case MTD_OOB_AUTO:

		break;



	case MTD_OOB_RAW:

		/* Replace the read_page algorithm temporary */

		read_page = chip->ecc.read_page;

		chip->ecc.read_page = nand_read_page_raw;

		break;



	default:
@@ -1359,8 +1355,6 @@ static int nand_read_oob(struct mtd_info *mtd, loff_t from, 
	else

		ret = nand_do_read_ops(mtd, from, ops);



	if (unlikely(ops->mode == MTD_OOB_RAW))

		chip->ecc.read_page = read_page;

 out:

	nand_release_device(mtd);

	return ret;
@@ -1479,7 +1473,7 @@ static void nand_write_page_syndrome(struct mtd_info *mtd, 
}



/**

 * nand_write_page - [INTERNAL] write one page

 * nand_write_page - [REPLACEABLE] write one page

 * @mtd:	MTD device structure

 * @chip:	NAND chip descriptor

 * @buf:	the data to write
@@ -1487,12 +1481,15 @@ static void nand_write_page_syndrome(struct mtd_info *mtd, 
 * @cached:	cached programming

 */

static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,

			   const uint8_t *buf, int page, int cached)

			   const uint8_t *buf, int page, int cached, int raw)

{

	int status;



	chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);



	if (unlikely(raw))

		chip->ecc.write_page_raw(mtd, chip, buf);

	else

		chip->ecc.write_page(mtd, chip, buf);



	/*
@@ -1636,7 +1633,8 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to, 
		if (unlikely(oob))

			oob = nand_fill_oob(chip, oob, ops);



		ret = nand_write_page(mtd, chip, buf, page, cached);

		ret = chip->write_page(mtd, chip, buf, page, cached,

				       (ops->mode == MTD_OOB_RAW));

		if (ret)

			break;
@@ -1769,8 +1767,6 @@ static int nand_do_write_oob(struct mtd_info *mtd, loff_t to, 
static int nand_write_oob(struct mtd_info *mtd, loff_t to,

			  struct mtd_oob_ops *ops)

{

	void (*write_page)(struct mtd_info *mtd, struct nand_chip *chip,

			  const uint8_t *buf) = NULL;

	struct nand_chip *chip = mtd->priv;

	int ret = -ENOTSUPP;
@@ -1788,12 +1784,7 @@ static int nand_write_oob(struct mtd_info *mtd, loff_t to, 
	switch(ops->mode) {

	case MTD_OOB_PLACE:

	case MTD_OOB_AUTO:

		break;



	case MTD_OOB_RAW:

		/* Replace the write_page algorithm temporary */

		write_page = chip->ecc.write_page;

		chip->ecc.write_page = nand_write_page_raw;

		break;



	default:
@@ -1805,8 +1796,6 @@ static int nand_write_oob(struct mtd_info *mtd, loff_t to, 
	else

		ret = nand_do_write_ops(mtd, to, ops);



	if (unlikely(ops->mode == MTD_OOB_RAW))

		chip->ecc.write_page = write_page;

 out:

	nand_release_device(mtd);

	return ret;
@@ -2383,10 +2372,18 @@ int nand_scan_tail(struct mtd_info *mtd) 
		}

	}



	if (!chip->write_page)

		chip->write_page = nand_write_page;



	/*

	 * check ECC mode, default to software if 3byte/512byte hardware ECC is

	 * selected and we have 256 byte pagesize fallback to software ECC

	 */

	if (!chip->ecc.read_page_raw)

		chip->ecc.read_page_raw = nand_read_page_raw;

	if (!chip->ecc.write_page_raw)

		chip->ecc.write_page_raw = nand_write_page_raw;



	switch (chip->ecc.mode) {

	case NAND_ECC_HW:

		/* Use standard hwecc read page function ? */
@@ -2444,6 +2441,7 @@ int nand_scan_tail(struct mtd_info *mtd) 
		chip->ecc.size = mtd->writesize;

		chip->ecc.bytes = 0;

		break;



	default:

		printk(KERN_WARNING "Invalid NAND_ECC_MODE %d\n",

		       chip->ecc.mode);

include/linux/mtd/nand.h

+11 −0
Original line number Diff line number Diff line
@@ -235,6 +235,8 @@ struct nand_hw_control { 
 *		be provided if an hardware ECC is available

 * @calculate:	function for ecc calculation or readback from ecc hardware

 * @correct:	function for ecc correction, matching to ecc generator (sw/hw)

 * @read_page_raw:	function to read a raw page without ECC

 * @write_page_raw:	function to write a raw page without ECC

 * @read_page:	function to read a page according to the ecc generator requirements

 * @write_page:	function to write a page according to the ecc generator requirements

 * @read_oob:	function to read chip OOB data
@@ -256,6 +258,12 @@ struct nand_ecc_ctrl { 
	int			(*correct)(struct mtd_info *mtd, uint8_t *dat,

					   uint8_t *read_ecc,

					   uint8_t *calc_ecc);

	int			(*read_page_raw)(struct mtd_info *mtd,

						 struct nand_chip *chip,

						 uint8_t *buf);

	void			(*write_page_raw)(struct mtd_info *mtd,

						  struct nand_chip *chip,

						  const uint8_t *buf);

	int			(*read_page)(struct mtd_info *mtd,

					     struct nand_chip *chip,

					     uint8_t *buf);
@@ -344,6 +352,7 @@ struct nand_buffers { 
 * @priv:		[OPTIONAL] pointer to private chip date

 * @errstat:		[OPTIONAL] hardware specific function to perform additional error status checks

 *			(determine if errors are correctable)

 * @write_page		[REPLACEABLE] High-level page write function

 */



struct nand_chip {
@@ -366,6 +375,8 @@ struct nand_chip { 
	void		(*erase_cmd)(struct mtd_info *mtd, int page);

	int		(*scan_bbt)(struct mtd_info *mtd);

	int		(*errstat)(struct mtd_info *mtd, struct nand_chip *this, int state, int status, int page);

	int		(*write_page)(struct mtd_info *mtd, struct nand_chip *chip,

				      const uint8_t *buf, int page, int cached, int raw);



	int		chip_delay;

	unsigned int	options;

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