diff options
Diffstat (limited to 'drivers/nvmem')
| -rw-r--r-- | drivers/nvmem/core.c | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index 8c16ae2e1308..d3c6676b3c0c 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -445,6 +445,148 @@ static void __nvmem_device_put(struct nvmem_device *nvmem) mutex_unlock(&nvmem_mutex); } +static int nvmem_match(struct device *dev, void *data) +{ + return !strcmp(dev_name(dev), data); +} + +static struct nvmem_device *nvmem_find(const char *name) +{ + struct device *d; + + d = bus_find_device(&nvmem_bus_type, NULL, (void *)name, nvmem_match); + + if (!d) + return NULL; + + return to_nvmem_device(d); +} + +#if IS_ENABLED(CONFIG_NVMEM) && IS_ENABLED(CONFIG_OF) +/** + * of_nvmem_device_get() - Get nvmem device from a given id + * + * @dev node: Device tree node that uses the nvmem device + * @id: nvmem name from nvmem-names property. + * + * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device + * on success. + */ +struct nvmem_device *of_nvmem_device_get(struct device_node *np, const char *id) +{ + + struct device_node *nvmem_np; + int index; + + index = of_property_match_string(np, "nvmem-names", id); + + nvmem_np = of_parse_phandle(np, "nvmem", index); + if (!nvmem_np) + return ERR_PTR(-EINVAL); + + return __nvmem_device_get(nvmem_np, NULL, NULL); +} +EXPORT_SYMBOL_GPL(of_nvmem_device_get); +#endif + +/** + * nvmem_device_get() - Get nvmem device from a given id + * + * @dev : Device that uses the nvmem device + * @id: nvmem name from nvmem-names property. + * + * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device + * on success. + */ +struct nvmem_device *nvmem_device_get(struct device *dev, const char *dev_name) +{ + if (dev->of_node) { /* try dt first */ + struct nvmem_device *nvmem; + + nvmem = of_nvmem_device_get(dev->of_node, dev_name); + + if (!IS_ERR(nvmem) || PTR_ERR(nvmem) == -EPROBE_DEFER) + return nvmem; + + } + + return nvmem_find(dev_name); +} +EXPORT_SYMBOL_GPL(nvmem_device_get); + +static int devm_nvmem_device_match(struct device *dev, void *res, void *data) +{ + struct nvmem_device **nvmem = res; + + if (WARN_ON(!nvmem || !*nvmem)) + return 0; + + return *nvmem == data; +} + +static void devm_nvmem_device_release(struct device *dev, void *res) +{ + nvmem_device_put(*(struct nvmem_device **)res); +} + +/** + * devm_nvmem_device_put() - put alredy got nvmem device + * + * @nvmem: pointer to nvmem device allocated by devm_nvmem_cell_get(), + * that needs to be released. + */ +void devm_nvmem_device_put(struct device *dev, struct nvmem_device *nvmem) +{ + int ret; + + ret = devres_release(dev, devm_nvmem_device_release, + devm_nvmem_device_match, nvmem); + + WARN_ON(ret); +} +EXPORT_SYMBOL_GPL(devm_nvmem_device_put); + +/** + * nvmem_device_put() - put alredy got nvmem device + * + * @nvmem: pointer to nvmem device that needs to be released. + */ +void nvmem_device_put(struct nvmem_device *nvmem) +{ + __nvmem_device_put(nvmem); +} +EXPORT_SYMBOL_GPL(nvmem_device_put); + +/** + * devm_nvmem_device_get() - Get nvmem cell of device form a given id + * + * @dev node: Device tree node that uses the nvmem cell + * @id: nvmem name in nvmems property. + * + * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_cell + * on success. The nvmem_cell will be freed by the automatically once the + * device is freed. + */ +struct nvmem_device *devm_nvmem_device_get(struct device *dev, const char *id) +{ + struct nvmem_device **ptr, *nvmem; + + ptr = devres_alloc(devm_nvmem_device_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + nvmem = nvmem_device_get(dev, id); + if (!IS_ERR(nvmem)) { + *ptr = nvmem; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return nvmem; +} +EXPORT_SYMBOL_GPL(devm_nvmem_device_get); + static struct nvmem_cell *nvmem_cell_get_from_list(const char *cell_id) { struct nvmem_cell *cell = NULL; @@ -806,6 +948,122 @@ int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len) } EXPORT_SYMBOL_GPL(nvmem_cell_write); +/** + * nvmem_device_cell_read() - Read a given nvmem device and cell + * + * @nvmem: nvmem device to read from. + * @info: nvmem cell info to be read. + * @buf: buffer pointer which will be populated on successful read. + * + * Return: length of successful bytes read on success and negative + * error code on error. + */ +ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem, + struct nvmem_cell_info *info, void *buf) +{ + struct nvmem_cell cell; + int rc; + ssize_t len; + + if (!nvmem || !nvmem->regmap) + return -EINVAL; + + rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); + if (IS_ERR_VALUE(rc)) + return rc; + + rc = __nvmem_cell_read(nvmem, &cell, buf, &len); + if (IS_ERR_VALUE(rc)) + return rc; + + return len; +} +EXPORT_SYMBOL_GPL(nvmem_device_cell_read); + +/** + * nvmem_device_cell_write() - Write cell to a given nvmem device + * + * @nvmem: nvmem device to be written to. + * @info: nvmem cell info to be written + * @buf: buffer to be written to cell. + * + * Return: length of bytes written or negative error code on failure. + * */ +int nvmem_device_cell_write(struct nvmem_device *nvmem, + struct nvmem_cell_info *info, void *buf) +{ + struct nvmem_cell cell; + int rc; + + if (!nvmem || !nvmem->regmap) + return -EINVAL; + + rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell); + if (IS_ERR_VALUE(rc)) + return rc; + + return nvmem_cell_write(&cell, buf, cell.bytes); +} +EXPORT_SYMBOL_GPL(nvmem_device_cell_write); + +/** + * nvmem_device_read() - Read from a given nvmem device + * + * @nvmem: nvmem device to read from. + * @offset: offset in nvmem device. + * @bytes: number of bytes to read. + * @buf: buffer pointer which will be populated on successful read. + * + * Return: length of successful bytes read on success and negative + * error code on error. + */ +int nvmem_device_read(struct nvmem_device *nvmem, + unsigned int offset, + size_t bytes, void *buf) +{ + int rc; + + if (!nvmem || !nvmem->regmap) + return -EINVAL; + + rc = regmap_raw_read(nvmem->regmap, offset, buf, bytes); + + if (IS_ERR_VALUE(rc)) + return rc; + + return bytes; +} +EXPORT_SYMBOL_GPL(nvmem_device_read); + +/** + * nvmem_device_write() - Write cell to a given nvmem device + * + * @nvmem: nvmem device to be written to. + * @offset: offset in nvmem device. + * @bytes: number of bytes to write. + * @buf: buffer to be written. + * + * Return: length of bytes written or negative error code on failure. + * */ +int nvmem_device_write(struct nvmem_device *nvmem, + unsigned int offset, + size_t bytes, void *buf) +{ + int rc; + + if (!nvmem || !nvmem->regmap) + return -EINVAL; + + rc = regmap_raw_write(nvmem->regmap, offset, buf, bytes); + + if (IS_ERR_VALUE(rc)) + return rc; + + + return bytes; +} +EXPORT_SYMBOL_GPL(nvmem_device_write); + static int __init nvmem_init(void) { return bus_register(&nvmem_bus_type); |