diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mtd/devices/m25p80.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index 4eeeb2d..069e34f 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -565,6 +565,96 @@ time_out: return ret; } +static int m25p80_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len) +{ + struct m25p *flash = mtd_to_m25p(mtd); + uint32_t offset = ofs; + uint8_t status_old, status_new; + int res = 0; + + mutex_lock(&flash->lock); + /* Wait until finished previous command */ + if (wait_till_ready(flash)) { + res = 1; + goto err; + } + + status_old = read_sr(flash); + + if (offset < flash->mtd.size-(flash->mtd.size/2)) + status_new = status_old | SR_BP2 | SR_BP1 | SR_BP0; + else if (offset < flash->mtd.size-(flash->mtd.size/4)) + status_new = (status_old & ~SR_BP0) | SR_BP2 | SR_BP1; + else if (offset < flash->mtd.size-(flash->mtd.size/8)) + status_new = (status_old & ~SR_BP1) | SR_BP2 | SR_BP0; + else if (offset < flash->mtd.size-(flash->mtd.size/16)) + status_new = (status_old & ~(SR_BP0|SR_BP1)) | SR_BP2; + else if (offset < flash->mtd.size-(flash->mtd.size/32)) + status_new = (status_old & ~SR_BP2) | SR_BP1 | SR_BP0; + else if (offset < flash->mtd.size-(flash->mtd.size/64)) + status_new = (status_old & ~(SR_BP2|SR_BP0)) | SR_BP1; + else + status_new = (status_old & ~(SR_BP2|SR_BP1)) | SR_BP0; + + /* Only modify protection if it will not unlock other areas */ + if ((status_new&(SR_BP2|SR_BP1|SR_BP0)) > + (status_old&(SR_BP2|SR_BP1|SR_BP0))) { + write_enable(flash); + if (write_sr(flash, status_new) < 0) { + res = 1; + goto err; + } + } + +err: mutex_unlock(&flash->lock); + return res; +} + +static int m25p80_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len) +{ + struct m25p *flash = mtd_to_m25p(mtd); + uint32_t offset = ofs; + uint8_t status_old, status_new; + int res = 0; + + mutex_lock(&flash->lock); + /* Wait until finished previous command */ + if (wait_till_ready(flash)) { + res = 1; + goto err; + } + + status_old = read_sr(flash); + + if (offset+len > flash->mtd.size-(flash->mtd.size/64)) + status_new = status_old & ~(SR_BP2|SR_BP1|SR_BP0); + else if (offset+len > flash->mtd.size-(flash->mtd.size/32)) + status_new = (status_old & ~(SR_BP2|SR_BP1)) | SR_BP0; + else if (offset+len > flash->mtd.size-(flash->mtd.size/16)) + status_new = (status_old & ~(SR_BP2|SR_BP0)) | SR_BP1; + else if (offset+len > flash->mtd.size-(flash->mtd.size/8)) + status_new = (status_old & ~SR_BP2) | SR_BP1 | SR_BP0; + else if (offset+len > flash->mtd.size-(flash->mtd.size/4)) + status_new = (status_old & ~(SR_BP0|SR_BP1)) | SR_BP2; + else if (offset+len > flash->mtd.size-(flash->mtd.size/2)) + status_new = (status_old & ~SR_BP1) | SR_BP2 | SR_BP0; + else + status_new = (status_old & ~SR_BP0) | SR_BP2 | SR_BP1; + + /* Only modify protection if it will not lock other areas */ + if ((status_new&(SR_BP2|SR_BP1|SR_BP0)) < + (status_old&(SR_BP2|SR_BP1|SR_BP0))) { + write_enable(flash); + if (write_sr(flash, status_new) < 0) { + res = 1; + goto err; + } + } + +err: mutex_unlock(&flash->lock); + return res; +} + /****************************************************************************/ /* @@ -899,6 +989,12 @@ static int m25p_probe(struct spi_device *spi) flash->mtd._erase = m25p80_erase; flash->mtd._read = m25p80_read; + /* flash protection support for STmicro chips */ + if (JEDEC_MFR(info->jedec_id) == CFI_MFR_ST) { + flash->mtd._lock = m25p80_lock; + flash->mtd._unlock = m25p80_unlock; + } + /* sst flash chips use AAI word program */ if (JEDEC_MFR(info->jedec_id) == CFI_MFR_SST) flash->mtd._write = sst_write; |