diff options
| -rw-r--r-- | drivers/mtd/mtdcore.c | 148 | ||||
| -rw-r--r-- | include/linux/mtd/mtd.h | 2 |
2 files changed, 150 insertions, 0 deletions
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 1fb43eea3599..3f2e20e22501 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -776,6 +776,146 @@ static void mtd_set_dev_defaults(struct mtd_info *mtd) mutex_init(&mtd->master.chrdev_lock); } +static ssize_t mtd_otp_size(struct mtd_info *mtd, bool is_user) +{ + struct otp_info *info = kmalloc(PAGE_SIZE, GFP_KERNEL); + ssize_t size = 0; + unsigned int i; + size_t retlen; + int ret; + + if (is_user) + ret = mtd_get_user_prot_info(mtd, PAGE_SIZE, &retlen, info); + else + ret = mtd_get_fact_prot_info(mtd, PAGE_SIZE, &retlen, info); + if (ret) + goto err; + + for (i = 0; i < retlen / sizeof(*info); i++) { + size += info->length; + info++; + } + + kfree(info); + return size; + +err: + kfree(info); + return ret; +} + +static struct nvmem_device *mtd_otp_nvmem_register(struct mtd_info *mtd, + const char *compatible, + int size, + nvmem_reg_read_t reg_read) +{ + struct nvmem_device *nvmem = NULL; + struct nvmem_config config = {}; + struct device_node *np; + + /* DT binding is optional */ + np = of_get_compatible_child(mtd->dev.of_node, compatible); + + /* OTP nvmem will be registered on the physical device */ + config.dev = mtd->dev.parent; + /* just reuse the compatible as name */ + config.name = compatible; + config.id = NVMEM_DEVID_NONE; + config.owner = THIS_MODULE; + config.type = NVMEM_TYPE_OTP; + config.root_only = true; + config.reg_read = reg_read; + config.size = size; + config.of_node = np; + config.priv = mtd; + + nvmem = nvmem_register(&config); + /* Just ignore if there is no NVMEM support in the kernel */ + if (IS_ERR(nvmem) && PTR_ERR(nvmem) == -EOPNOTSUPP) + nvmem = NULL; + + of_node_put(np); + + return nvmem; +} + +static int mtd_nvmem_user_otp_reg_read(void *priv, unsigned int offset, + void *val, size_t bytes) +{ + struct mtd_info *mtd = priv; + size_t retlen; + int ret; + + ret = mtd_read_user_prot_reg(mtd, offset, bytes, &retlen, val); + if (ret) + return ret; + + return retlen == bytes ? 0 : -EIO; +} + +static int mtd_nvmem_fact_otp_reg_read(void *priv, unsigned int offset, + void *val, size_t bytes) +{ + struct mtd_info *mtd = priv; + size_t retlen; + int ret; + + ret = mtd_read_fact_prot_reg(mtd, offset, bytes, &retlen, val); + if (ret) + return ret; + + return retlen == bytes ? 0 : -EIO; +} + +static int mtd_otp_nvmem_add(struct mtd_info *mtd) +{ + struct nvmem_device *nvmem; + ssize_t size; + int err; + + if (mtd->_get_user_prot_info && mtd->_read_user_prot_reg) { + size = mtd_otp_size(mtd, true); + if (size < 0) + return size; + + if (size > 0) { + nvmem = mtd_otp_nvmem_register(mtd, "user-otp", size, + mtd_nvmem_user_otp_reg_read); + if (IS_ERR(nvmem)) { + dev_err(&mtd->dev, "Failed to register OTP NVMEM device\n"); + return PTR_ERR(nvmem); + } + mtd->otp_user_nvmem = nvmem; + } + } + + if (mtd->_get_fact_prot_info && mtd->_read_fact_prot_reg) { + size = mtd_otp_size(mtd, false); + if (size < 0) { + err = size; + goto err; + } + + if (size > 0) { + nvmem = mtd_otp_nvmem_register(mtd, "factory-otp", size, + mtd_nvmem_fact_otp_reg_read); + if (IS_ERR(nvmem)) { + dev_err(&mtd->dev, "Failed to register OTP NVMEM device\n"); + err = PTR_ERR(nvmem); + goto err; + } + mtd->otp_factory_nvmem = nvmem; + } + } + + return 0; + +err: + if (mtd->otp_user_nvmem) + nvmem_unregister(mtd->otp_user_nvmem); + return err; +} + /** * mtd_device_parse_register - parse partitions and register an MTD device. * @@ -851,6 +991,8 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types, register_reboot_notifier(&mtd->reboot_notifier); } + ret = mtd_otp_nvmem_add(mtd); + out: if (ret && device_is_registered(&mtd->dev)) del_mtd_device(mtd); @@ -872,6 +1014,12 @@ int mtd_device_unregister(struct mtd_info *master) if (master->_reboot) unregister_reboot_notifier(&master->reboot_notifier); + if (master->otp_user_nvmem) + nvmem_unregister(master->otp_user_nvmem); + + if (master->otp_factory_nvmem) + nvmem_unregister(master->otp_factory_nvmem); + err = del_mtd_partitions(master); if (err) return err; diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index a89955f3cbc8..88227044fc86 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -380,6 +380,8 @@ struct mtd_info { int usecount; struct mtd_debug_info dbg; struct nvmem_device *nvmem; + struct nvmem_device *otp_user_nvmem; + struct nvmem_device *otp_factory_nvmem; /* * Parent device from the MTD partition point of view. |