| Message ID | 84804381.386644.1512497624913.JavaMail.zimbra@xes-inc.com |
|---|---|
| State | Accepted |
| Delegated to: | Cyrille Pitchen |
| Headers | show |
| Series | [v2] mtd: spi-nor: Check that BP bits are set properly | expand |
Le 05/12/2017 à 19:13, Aaron Sierra a écrit : > Previously, the lock and unlock functions returned success even if the > BP bits were not actually updated in the status register due to > hardware write protection. Introduce write_sr_and_check() to write and > read back the status register to ensure the desired BP bits are > actually set as requested. > > Signed-off-by: Joe Schultz <jschultz@xes-inc.com> > Signed-off-by: Aaron Sierra <asierra@xes-inc.com> Applied to the spi-nor/next branch of l2-mtd Thanks! > --- > drivers/mtd/spi-nor/spi-nor.c | 35 +++++++++++++++++++++++------------ > 1 file changed, 23 insertions(+), 12 deletions(-) > > v2: * Removed unnecessary spi_nor_wait_till_ready() call > * Renamed "new" variable to "status_new" > > diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c > index bc266f7..c3ee168 100644 > --- a/drivers/mtd/spi-nor/spi-nor.c > +++ b/drivers/mtd/spi-nor/spi-nor.c > @@ -552,6 +552,27 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) > return ret; > } > > +/* Write status register and ensure bits in mask match written values */ > +static int write_sr_and_check(struct spi_nor *nor, u8 status_new, u8 mask) > +{ > + int ret; > + > + write_enable(nor); > + ret = write_sr(nor, status_new); > + if (ret) > + return ret; > + > + ret = spi_nor_wait_till_ready(nor); > + if (ret) > + return ret; > + > + ret = read_sr(nor); > + if (ret < 0) > + return ret; > + > + return ((ret & mask) != (status_new & mask)) ? -EIO : 0; > +} > + > static void stm_get_locked_range(struct spi_nor *nor, u8 sr, loff_t *ofs, > uint64_t *len) > { > @@ -650,7 +671,6 @@ static int stm_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) > loff_t lock_len; > bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB; > bool use_top; > - int ret; > > status_old = read_sr(nor); > if (status_old < 0) > @@ -714,11 +734,7 @@ static int stm_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) > if ((status_new & mask) < (status_old & mask)) > return -EINVAL; > > - write_enable(nor); > - ret = write_sr(nor, status_new); > - if (ret) > - return ret; > - return spi_nor_wait_till_ready(nor); > + return write_sr_and_check(nor, status_new, mask); > } > > /* > @@ -735,7 +751,6 @@ static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) > loff_t lock_len; > bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB; > bool use_top; > - int ret; > > status_old = read_sr(nor); > if (status_old < 0) > @@ -802,11 +817,7 @@ static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) > if ((status_new & mask) > (status_old & mask)) > return -EINVAL; > > - write_enable(nor); > - ret = write_sr(nor, status_new); > - if (ret) > - return ret; > - return spi_nor_wait_till_ready(nor); > + return write_sr_and_check(nor, status_new, mask); > } > > /* >
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index bc266f7..c3ee168 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -552,6 +552,27 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) return ret; } +/* Write status register and ensure bits in mask match written values */ +static int write_sr_and_check(struct spi_nor *nor, u8 status_new, u8 mask) +{ + int ret; + + write_enable(nor); + ret = write_sr(nor, status_new); + if (ret) + return ret; + + ret = spi_nor_wait_till_ready(nor); + if (ret) + return ret; + + ret = read_sr(nor); + if (ret < 0) + return ret; + + return ((ret & mask) != (status_new & mask)) ? -EIO : 0; +} + static void stm_get_locked_range(struct spi_nor *nor, u8 sr, loff_t *ofs, uint64_t *len) { @@ -650,7 +671,6 @@ static int stm_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) loff_t lock_len; bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB; bool use_top; - int ret; status_old = read_sr(nor); if (status_old < 0) @@ -714,11 +734,7 @@ static int stm_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) if ((status_new & mask) < (status_old & mask)) return -EINVAL; - write_enable(nor); - ret = write_sr(nor, status_new); - if (ret) - return ret; - return spi_nor_wait_till_ready(nor); + return write_sr_and_check(nor, status_new, mask); } /* @@ -735,7 +751,6 @@ static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) loff_t lock_len; bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB; bool use_top; - int ret; status_old = read_sr(nor); if (status_old < 0) @@ -802,11 +817,7 @@ static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) if ((status_new & mask) > (status_old & mask)) return -EINVAL; - write_enable(nor); - ret = write_sr(nor, status_new); - if (ret) - return ret; - return spi_nor_wait_till_ready(nor); + return write_sr_and_check(nor, status_new, mask); } /*