diff options
| -rw-r--r-- | drivers/mtd/devices/m25p80.c | 69 |
1 files changed, 40 insertions, 29 deletions
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index 47486fbd777..e6892851e81 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -709,6 +709,14 @@ static const struct spi_device_id *__devinit jedec_probe(struct spi_device *spi) jedec = jedec << 8; jedec |= id[2]; + /* + * Some chips (like Numonyx M25P80) have JEDEC and non-JEDEC variants, + * which depend on technology process. Officially RDID command doesn't + * exist for non-JEDEC chips, but for compatibility they return ID 0. + */ + if (jedec == 0) + return NULL; + ext_jedec = id[3] << 8 | id[4]; for (tmp = 0; tmp < ARRAY_SIZE(m25p_ids) - 1; tmp++) { @@ -730,7 +738,7 @@ static const struct spi_device_id *__devinit jedec_probe(struct spi_device *spi) */ static int __devinit m25p_probe(struct spi_device *spi) { - const struct spi_device_id *id; + const struct spi_device_id *id = spi_get_device_id(spi); struct flash_platform_data *data; struct m25p *flash; struct flash_info *info; @@ -743,41 +751,44 @@ static int __devinit m25p_probe(struct spi_device *spi) */ data = spi->dev.platform_data; if (data && data->type) { + const struct spi_device_id *plat_id; + for (i = 0; i < ARRAY_SIZE(m25p_ids) - 1; i++) { - id = &m25p_ids[i]; - info = (void *)m25p_ids[i].driver_data; - if (strcmp(data->type, id->name)) + plat_id = &m25p_ids[i]; + if (strcmp(data->type, plat_id->name)) continue; break; } - /* unrecognized chip? */ - if (i == ARRAY_SIZE(m25p_ids) - 1) { - DEBUG(MTD_DEBUG_LEVEL0, "%s: unrecognized id %s\n", - dev_name(&spi->dev), data->type); - info = NULL; - - /* recognized; is that chip really what's there? */ - } else if (info->jedec_id) { - id = jedec_probe(spi); - - if (id != &m25p_ids[i]) { - dev_warn(&spi->dev, "found %s, expected %s\n", - id ? id->name : "UNKNOWN", - m25p_ids[i].name); - info = NULL; - } - } - } else { - id = jedec_probe(spi); - if (!id) - id = spi_get_device_id(spi); - - info = (void *)id->driver_data; + if (plat_id) + id = plat_id; + else + dev_warn(&spi->dev, "unrecognized id %s\n", data->type); } - if (!info) - return -ENODEV; + info = (void *)id->driver_data; + + if (info->jedec_id) { + const struct spi_device_id *jid; + + jid = jedec_probe(spi); + if (!jid) { + dev_info(&spi->dev, "non-JEDEC variant of %s\n", + id->name); + } else if (jid != id) { + /* + * JEDEC knows better, so overwrite platform ID. We + * can't trust partitions any longer, but we'll let + * mtd apply them anyway, since some partitions may be + * marked read-only, and we don't want to lose that + * information, even if it's not 100% accurate. + */ + dev_warn(&spi->dev, "found %s, expected %s\n", + jid->name, id->name); + id = jid; + info = (void *)jid->driver_data; + } + } flash = kzalloc(sizeof *flash, GFP_KERNEL); if (!flash) |