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| author | Leonard Crestez <leonard.crestez@nxp.com> | 2017-07-26 11:34:46 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-08-28 17:33:23 +0200 |
| commit | d026d70a2e9460dc701d20b48672b80a2656006d (patch) | |
| tree | 24acc74a69f48c4f163b75c9764305f19f33da68 | |
| parent | nvmem: Convert to using %pOF instead of full_name (diff) | |
| download | linux-d026d70a2e9460dc701d20b48672b80a2656006d.tar.xz linux-d026d70a2e9460dc701d20b48672b80a2656006d.zip | |
nvmem: core: Add nvmem_cell_read_u32
This function does a quick and easy read of an u32 value without any
kind of resource management code on the consumer side.
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/nvmem/core.c | 37 | ||||
| -rw-r--r-- | include/linux/nvmem-consumer.h | 7 |
2 files changed, 44 insertions, 0 deletions
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index b0c60338296a..72a60dc8a429 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -1111,6 +1111,43 @@ int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len) EXPORT_SYMBOL_GPL(nvmem_cell_write); /** + * nvmem_cell_read_u32() - Read a cell value as an u32 + * + * @dev: Device that requests the nvmem cell. + * @cell_id: Name of nvmem cell to read. + * @val: pointer to output value. + * + * Return: 0 on success or negative errno. + */ +int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val) +{ + struct nvmem_cell *cell; + void *buf; + size_t len; + + cell = nvmem_cell_get(dev, cell_id); + if (IS_ERR(cell)) + return PTR_ERR(cell); + + buf = nvmem_cell_read(cell, &len); + if (IS_ERR(buf)) { + nvmem_cell_put(cell); + return PTR_ERR(buf); + } + if (len != sizeof(*val)) { + kfree(buf); + nvmem_cell_put(cell); + return -EINVAL; + } + memcpy(val, buf, sizeof(*val)); + + kfree(buf); + nvmem_cell_put(cell); + return 0; +} +EXPORT_SYMBOL_GPL(nvmem_cell_read_u32); + +/** * nvmem_device_cell_read() - Read a given nvmem device and cell * * @nvmem: nvmem device to read from. diff --git a/include/linux/nvmem-consumer.h b/include/linux/nvmem-consumer.h index c2256d746543..efafccffaee8 100644 --- a/include/linux/nvmem-consumer.h +++ b/include/linux/nvmem-consumer.h @@ -35,6 +35,7 @@ void nvmem_cell_put(struct nvmem_cell *cell); void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell); void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len); int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len); +int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val); /* direct nvmem device read/write interface */ struct nvmem_device *nvmem_device_get(struct device *dev, const char *name); @@ -85,6 +86,12 @@ static inline int nvmem_cell_write(struct nvmem_cell *cell, return -ENOSYS; } +static inline int nvmem_cell_read_u32(struct device *dev, + const char *cell_id, u32 *val) +{ + return -ENOSYS; +} + static inline struct nvmem_device *nvmem_device_get(struct device *dev, const char *name) { |