Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit d026d70a authored by Leonard Crestez's avatar Leonard Crestez Committed by Greg Kroah-Hartman
Browse files

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: default avatarLeonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: default avatarShawn Guo <shawnguo@kernel.org>
Signed-off-by: default avatarSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 5f214ccd

drivers/nvmem/core.c

+37 −0
Original line number Diff line number Diff line
@@ -1110,6 +1110,43 @@ 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

 *

include/linux/nvmem-consumer.h

+7 −0
Original line number Diff line number Diff line
@@ -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)

{