Commit 8c174d15 authored by Michael Walle's avatar Michael Walle Committed by Vignesh Raghavendra
Browse files

mtd: spi-nor: atmel: fix unlock_all() for AT25FS010/040 



These flashes have some weird BP bits mapping which aren't supported in
the current locking code. Just add a simple unlock op to unprotect the
entire flash array which is needed for legacy behavior.

Fixes: 3e0930f1 ("mtd: spi-nor: Rework the disabling of block write protection")
Signed-off-by: default avatarMichael Walle <michael@walle.cc>
Signed-off-by: default avatarVignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: default avatarTudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20201203162959.29589-7-michael@walle.cc
parent afcf93e9

drivers/mtd/spi-nor/atmel.c

+51 −2
Original line number Diff line number Diff line
@@ -8,10 +8,59 @@ 


#include "core.h"



/*

 * The Atmel AT25FS010/AT25FS040 parts have some weird configuration for the

 * block protection bits. We don't support them. But legacy behavior in linux

 * is to unlock the whole flash array on startup. Therefore, we have to support

 * exactly this operation.

 */

static int atmel_at25fs_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)

{

	return -EOPNOTSUPP;

}



static int atmel_at25fs_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)

{

	int ret;



	/* We only support unlocking the whole flash array */

	if (ofs || len != nor->params->size)

		return -EINVAL;



	/* Write 0x00 to the status register to disable write protection */

	ret = spi_nor_write_sr_and_check(nor, 0);

	if (ret)

		dev_dbg(nor->dev, "unable to clear BP bits, WP# asserted?\n");



	return ret;

}



static int atmel_at25fs_is_locked(struct spi_nor *nor, loff_t ofs, uint64_t len)

{

	return -EOPNOTSUPP;

}



static const struct spi_nor_locking_ops atmel_at25fs_locking_ops = {

	.lock = atmel_at25fs_lock,

	.unlock = atmel_at25fs_unlock,

	.is_locked = atmel_at25fs_is_locked,

};



static void atmel_at25fs_default_init(struct spi_nor *nor)

{

	nor->params->locking_ops = &atmel_at25fs_locking_ops;

}



static const struct spi_nor_fixups atmel_at25fs_fixups = {

	.default_init = atmel_at25fs_default_init,

};



static const struct flash_info atmel_parts[] = {

	/* Atmel -- some are (confusingly) marketed as "DataFlash" */

	{ "at25fs010",  INFO(0x1f6601, 0, 32 * 1024,   4, SECT_4K | SPI_NOR_HAS_LOCK) },

	{ "at25fs040",  INFO(0x1f6604, 0, 64 * 1024,   8, SECT_4K | SPI_NOR_HAS_LOCK) },

	{ "at25fs010",  INFO(0x1f6601, 0, 32 * 1024,   4, SECT_4K | SPI_NOR_HAS_LOCK)

		.fixups = &atmel_at25fs_fixups },

	{ "at25fs040",  INFO(0x1f6604, 0, 64 * 1024,   8, SECT_4K | SPI_NOR_HAS_LOCK)

		.fixups = &atmel_at25fs_fixups },



	{ "at25df041a", INFO(0x1f4401, 0, 64 * 1024,   8, SECT_4K | SPI_NOR_HAS_LOCK) },

	{ "at25df321",  INFO(0x1f4700, 0, 64 * 1024,  64, SECT_4K | SPI_NOR_HAS_LOCK) },

drivers/mtd/spi-nor/core.c

+1 −1
Original line number Diff line number Diff line
@@ -1049,7 +1049,7 @@ static int spi_nor_write_16bit_cr_and_check(struct spi_nor *nor, u8 cr) 
 *

 * Return: 0 on success, -errno otherwise.

 */

static int spi_nor_write_sr_and_check(struct spi_nor *nor, u8 sr1)

int spi_nor_write_sr_and_check(struct spi_nor *nor, u8 sr1)

{

	if (nor->flags & SNOR_F_HAS_16BIT_SR)

		return spi_nor_write_16bit_sr_and_check(nor, sr1);

drivers/mtd/spi-nor/core.h

+1 −0
Original line number Diff line number Diff line
@@ -433,6 +433,7 @@ void spi_nor_unlock_and_unprep(struct spi_nor *nor); 
int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor);

int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor);

int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor);

int spi_nor_write_sr_and_check(struct spi_nor *nor, u8 sr1);



int spi_nor_xread_sr(struct spi_nor *nor, u8 *sr);

ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len,

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