1 /* SPDX-License-Identifier: GPL-2.0 */
3 * nvmem framework provider.
5 * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
6 * Copyright (C) 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
9 #ifndef _LINUX_NVMEM_PROVIDER_H
10 #define _LINUX_NVMEM_PROVIDER_H
12 #include <linux/err.h>
13 #include <linux/errno.h>
16 struct nvmem_cell_info
;
17 typedef int (*nvmem_reg_read_t
)(void *priv
, unsigned int offset
,
18 void *val
, size_t bytes
);
19 typedef int (*nvmem_reg_write_t
)(void *priv
, unsigned int offset
,
20 void *val
, size_t bytes
);
23 NVMEM_TYPE_UNKNOWN
= 0,
26 NVMEM_TYPE_BATTERY_BACKED
,
30 * struct nvmem_config - NVMEM device configuration
32 * @dev: Parent device.
33 * @name: Optional name.
34 * @id: Optional device ID used in full name. Ignored if name is NULL.
35 * @owner: Pointer to exporter module. Used for refcounting.
36 * @cells: Optional array of pre-defined NVMEM cells.
37 * @ncells: Number of elements in cells.
38 * @type: Type of the nvmem storage
39 * @read_only: Device is read-only.
40 * @root_only: Device is accessibly to root only.
41 * @no_of_node: Device should not use the parent's of_node even if it's !NULL.
42 * @reg_read: Callback to read data.
43 * @reg_write: Callback to write data.
45 * @word_size: Minimum read/write access granularity.
46 * @stride: Minimum read/write access stride.
47 * @priv: User context passed to read/write callbacks.
49 * Note: A default "nvmem<id>" name will be assigned to the device if
50 * no name is specified in its configuration. In such case "<id>" is
51 * generated with ida_simple_get() and provided id field is ignored.
53 * Note: Specifying name and setting id to -1 implies a unique device
54 * whose name is provided as-is (kept unaltered).
61 const struct nvmem_cell_info
*cells
;
67 nvmem_reg_read_t reg_read
;
68 nvmem_reg_write_t reg_write
;
73 /* To be only used by old driver/misc/eeprom drivers */
75 struct device
*base_dev
;
79 * struct nvmem_cell_table - NVMEM cell definitions for given provider
81 * @nvmem_name: Provider name.
82 * @cells: Array of cell definitions.
83 * @ncells: Number of cell definitions in the array.
86 * This structure together with related helper functions is provided for users
87 * that don't can't access the nvmem provided structure but wish to register
88 * cell definitions for it e.g. board files registering an EEPROM device.
90 struct nvmem_cell_table
{
91 const char *nvmem_name
;
92 const struct nvmem_cell_info
*cells
;
94 struct list_head node
;
97 #if IS_ENABLED(CONFIG_NVMEM)
99 struct nvmem_device
*nvmem_register(const struct nvmem_config
*cfg
);
100 void nvmem_unregister(struct nvmem_device
*nvmem
);
102 struct nvmem_device
*devm_nvmem_register(struct device
*dev
,
103 const struct nvmem_config
*cfg
);
105 int devm_nvmem_unregister(struct device
*dev
, struct nvmem_device
*nvmem
);
107 void nvmem_add_cell_table(struct nvmem_cell_table
*table
);
108 void nvmem_del_cell_table(struct nvmem_cell_table
*table
);
112 static inline struct nvmem_device
*nvmem_register(const struct nvmem_config
*c
)
114 return ERR_PTR(-EOPNOTSUPP
);
117 static inline void nvmem_unregister(struct nvmem_device
*nvmem
) {}
119 static inline struct nvmem_device
*
120 devm_nvmem_register(struct device
*dev
, const struct nvmem_config
*c
)
122 return nvmem_register(c
);
126 devm_nvmem_unregister(struct device
*dev
, struct nvmem_device
*nvmem
)
131 static inline void nvmem_add_cell_table(struct nvmem_cell_table
*table
) {}
132 static inline void nvmem_del_cell_table(struct nvmem_cell_table
*table
) {}
134 #endif /* CONFIG_NVMEM */
135 #endif /* ifndef _LINUX_NVMEM_PROVIDER_H */