linux-stable/include/linux/nvmem-consumer.h
Andreas Färber 5037d368b2 nvmem: core: Add nvmem_cell_read_u8()
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 <afaerber@suse.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200722100705.7772-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-29 17:12:08 +02:00

245 lines
6.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* nvmem framework consumer.
*
* Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
* Copyright (C) 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
*/
#ifndef _LINUX_NVMEM_CONSUMER_H
#define _LINUX_NVMEM_CONSUMER_H
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/notifier.h>
struct device;
struct device_node;
/* consumer cookie */
struct nvmem_cell;
struct nvmem_device;
struct nvmem_cell_info {
const char *name;
unsigned int offset;
unsigned int bytes;
unsigned int bit_offset;
unsigned int nbits;
};
/**
* struct nvmem_cell_lookup - cell lookup entry
*
* @nvmem_name: Name of the provider.
* @cell_name: Name of the nvmem cell as defined in the name field of
* struct nvmem_cell_info.
* @dev_id: Name of the consumer device that will be associated with
* this cell.
* @con_id: Connector id for this cell lookup.
*/
struct nvmem_cell_lookup {
const char *nvmem_name;
const char *cell_name;
const char *dev_id;
const char *con_id;
struct list_head node;
};
enum {
NVMEM_ADD = 1,
NVMEM_REMOVE,
NVMEM_CELL_ADD,
NVMEM_CELL_REMOVE,
};
#if IS_ENABLED(CONFIG_NVMEM)
/* Cell based interface */
struct nvmem_cell *nvmem_cell_get(struct device *dev, const char *id);
struct nvmem_cell *devm_nvmem_cell_get(struct device *dev, const char *id);
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);
/* direct nvmem device read/write interface */
struct nvmem_device *nvmem_device_get(struct device *dev, const char *name);
struct nvmem_device *devm_nvmem_device_get(struct device *dev,
const char *name);
void nvmem_device_put(struct nvmem_device *nvmem);
void devm_nvmem_device_put(struct device *dev, struct nvmem_device *nvmem);
int nvmem_device_read(struct nvmem_device *nvmem, unsigned int offset,
size_t bytes, void *buf);
int nvmem_device_write(struct nvmem_device *nvmem, unsigned int offset,
size_t bytes, void *buf);
ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem,
struct nvmem_cell_info *info, void *buf);
int nvmem_device_cell_write(struct nvmem_device *nvmem,
struct nvmem_cell_info *info, void *buf);
const char *nvmem_dev_name(struct nvmem_device *nvmem);
void nvmem_add_cell_lookups(struct nvmem_cell_lookup *entries,
size_t nentries);
void nvmem_del_cell_lookups(struct nvmem_cell_lookup *entries,
size_t nentries);
int nvmem_register_notifier(struct notifier_block *nb);
int nvmem_unregister_notifier(struct notifier_block *nb);
struct nvmem_device *nvmem_device_find(void *data,
int (*match)(struct device *dev, const void *data));
#else
static inline struct nvmem_cell *nvmem_cell_get(struct device *dev,
const char *id)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline struct nvmem_cell *devm_nvmem_cell_get(struct device *dev,
const char *id)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline void devm_nvmem_cell_put(struct device *dev,
struct nvmem_cell *cell)
{
}
static inline void nvmem_cell_put(struct nvmem_cell *cell)
{
}
static inline void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline int nvmem_cell_write(struct nvmem_cell *cell,
void *buf, size_t len)
{
return -EOPNOTSUPP;
}
static inline int nvmem_cell_read_u16(struct device *dev,
const char *cell_id, u16 *val)
{
return -EOPNOTSUPP;
}
static inline int nvmem_cell_read_u32(struct device *dev,
const char *cell_id, u32 *val)
{
return -EOPNOTSUPP;
}
static inline int nvmem_cell_read_u64(struct device *dev,
const char *cell_id, u64 *val)
{
return -EOPNOTSUPP;
}
static inline struct nvmem_device *nvmem_device_get(struct device *dev,
const char *name)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline struct nvmem_device *devm_nvmem_device_get(struct device *dev,
const char *name)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline void nvmem_device_put(struct nvmem_device *nvmem)
{
}
static inline void devm_nvmem_device_put(struct device *dev,
struct nvmem_device *nvmem)
{
}
static inline ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem,
struct nvmem_cell_info *info,
void *buf)
{
return -EOPNOTSUPP;
}
static inline int nvmem_device_cell_write(struct nvmem_device *nvmem,
struct nvmem_cell_info *info,
void *buf)
{
return -EOPNOTSUPP;
}
static inline int nvmem_device_read(struct nvmem_device *nvmem,
unsigned int offset, size_t bytes,
void *buf)
{
return -EOPNOTSUPP;
}
static inline int nvmem_device_write(struct nvmem_device *nvmem,
unsigned int offset, size_t bytes,
void *buf)
{
return -EOPNOTSUPP;
}
static inline const char *nvmem_dev_name(struct nvmem_device *nvmem)
{
return NULL;
}
static inline void
nvmem_add_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) {}
static inline void
nvmem_del_cell_lookups(struct nvmem_cell_lookup *entries, size_t nentries) {}
static inline int nvmem_register_notifier(struct notifier_block *nb)
{
return -EOPNOTSUPP;
}
static inline int nvmem_unregister_notifier(struct notifier_block *nb)
{
return -EOPNOTSUPP;
}
static inline struct nvmem_device *nvmem_device_find(void *data,
int (*match)(struct device *dev, const void *data))
{
return NULL;
}
#endif /* CONFIG_NVMEM */
#if IS_ENABLED(CONFIG_NVMEM) && IS_ENABLED(CONFIG_OF)
struct nvmem_cell *of_nvmem_cell_get(struct device_node *np,
const char *id);
struct nvmem_device *of_nvmem_device_get(struct device_node *np,
const char *name);
#else
static inline struct nvmem_cell *of_nvmem_cell_get(struct device_node *np,
const char *id)
{
return ERR_PTR(-EOPNOTSUPP);
}
static inline struct nvmem_device *of_nvmem_device_get(struct device_node *np,
const char *name)
{
return ERR_PTR(-EOPNOTSUPP);
}
#endif /* CONFIG_NVMEM && CONFIG_OF */
#endif /* ifndef _LINUX_NVMEM_CONSUMER_H */