From: Michael Walle michael@walle.cc
[ Upstream commit 8c174d1511d235ed6c049dcb2b704777ad0df7a5 ]
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: 3e0930f109e7 ("mtd: spi-nor: Rework the disabling of block write protection") Signed-off-by: Michael Walle michael@walle.cc Signed-off-by: Vignesh Raghavendra vigneshr@ti.com Reviewed-by: Tudor Ambarus tudor.ambarus@microchip.com Link: https://lore.kernel.org/r/20201203162959.29589-7-michael@walle.cc Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mtd/spi-nor/atmel.c | 53 +++++++++++++++++++++++++++++++++++-- drivers/mtd/spi-nor/core.c | 2 +- drivers/mtd/spi-nor/core.h | 1 + 3 files changed, 53 insertions(+), 3 deletions(-)
diff --git a/drivers/mtd/spi-nor/atmel.c b/drivers/mtd/spi-nor/atmel.c index 49d392c6c8bc5..deacf87a68a06 100644 --- a/drivers/mtd/spi-nor/atmel.c +++ b/drivers/mtd/spi-nor/atmel.c @@ -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) }, diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index 61b00d4965475..ad6c79d9a7f86 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -906,7 +906,7 @@ 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); diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h index 6f2f6b27173fd..6f62ee861231a 100644 --- a/drivers/mtd/spi-nor/core.h +++ b/drivers/mtd/spi-nor/core.h @@ -409,6 +409,7 @@ 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,