From 5037d368b2c2c90e9432d477e5562dce1c33d5c9 Mon Sep 17 00:00:00 2001 From: Andreas Färber Date: Wed, 22 Jul 2020 11:06:57 +0100 Subject: nvmem: core: Add nvmem_cell_read_u8() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Complement the u16, u32 and u64 helpers with a u8 variant to ease accessing byte-sized values. This helper will be useful for Realtek Digital Home Center platforms, which store some byte and sub-byte sized values in non-volatile memory. Signed-off-by: Andreas Färber Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20200722100705.7772-7-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/nvmem/core.c | 15 +++++++++++++++ include/linux/nvmem-consumer.h | 1 + 2 files changed, 16 insertions(+) diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index 95bed31391cd..d6bacc878500 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -1374,6 +1374,21 @@ static int nvmem_cell_read_common(struct device *dev, const char *cell_id, return 0; } +/** + * nvmem_cell_read_u8() - Read a cell value as a u8 + * + * @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_u8(struct device *dev, const char *cell_id, u8 *val) +{ + return nvmem_cell_read_common(dev, cell_id, val, sizeof(*val)); +} +EXPORT_SYMBOL_GPL(nvmem_cell_read_u8); + /** * nvmem_cell_read_u16() - Read a cell value as a u16 * diff --git a/include/linux/nvmem-consumer.h b/include/linux/nvmem-consumer.h index 1b311d27c9b8..052293f4cbdb 100644 --- a/include/linux/nvmem-consumer.h +++ b/include/linux/nvmem-consumer.h @@ -61,6 +61,7 @@ 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_u8(struct device *dev, const char *cell_id, u8 *val); int nvmem_cell_read_u16(struct device *dev, const char *cell_id, u16 *val); int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val); int nvmem_cell_read_u64(struct device *dev, const char *cell_id, u64 *val); -- cgit v1.2.3