1 /* 2 * nvmem framework provider. 3 * 4 * Copyright (C) 2015 Srinivas Kandagatla <[email protected]> 5 * Copyright (C) 2013 Maxime Ripard <[email protected]> 6 * 7 * This file is licensed under the terms of the GNU General Public 8 * License version 2. This program is licensed "as is" without any 9 * warranty of any kind, whether express or implied. 10 */ 11 12 #ifndef _LINUX_NVMEM_PROVIDER_H 13 #define _LINUX_NVMEM_PROVIDER_H 14 15 #include <linux/err.h> 16 #include <linux/errno.h> 17 18 struct nvmem_device; 19 struct nvmem_cell_info; 20 typedef int (*nvmem_reg_read_t)(void *priv, unsigned int offset, 21 void *val, size_t bytes); 22 typedef int (*nvmem_reg_write_t)(void *priv, unsigned int offset, 23 void *val, size_t bytes); 24 25 /** 26 * struct nvmem_config - NVMEM device configuration 27 * 28 * @dev: Parent device. 29 * @name: Optional name. 30 * @id: Optional device ID used in full name. Ignored if name is NULL. 31 * @owner: Pointer to exporter module. Used for refcounting. 32 * @cells: Optional array of pre-defined NVMEM cells. 33 * @ncells: Number of elements in cells. 34 * @read_only: Device is read-only. 35 * @root_only: Device is accessibly to root only. 36 * @reg_read: Callback to read data. 37 * @reg_write: Callback to write data. 38 * @size: Device size. 39 * @word_size: Minimum read/write access granularity. 40 * @stride: Minimum read/write access stride. 41 * @priv: User context passed to read/write callbacks. 42 * 43 * Note: A default "nvmem<id>" name will be assigned to the device if 44 * no name is specified in its configuration. In such case "<id>" is 45 * generated with ida_simple_get() and provided id field is ignored. 46 * 47 * Note: Specifying name and setting id to -1 implies a unique device 48 * whose name is provided as-is (kept unaltered). 49 */ 50 struct nvmem_config { 51 struct device *dev; 52 const char *name; 53 int id; 54 struct module *owner; 55 const struct nvmem_cell_info *cells; 56 int ncells; 57 bool read_only; 58 bool root_only; 59 nvmem_reg_read_t reg_read; 60 nvmem_reg_write_t reg_write; 61 int size; 62 int word_size; 63 int stride; 64 void *priv; 65 /* To be only used by old driver/misc/eeprom drivers */ 66 bool compat; 67 struct device *base_dev; 68 }; 69 70 #if IS_ENABLED(CONFIG_NVMEM) 71 72 struct nvmem_device *nvmem_register(const struct nvmem_config *cfg); 73 int nvmem_unregister(struct nvmem_device *nvmem); 74 75 struct nvmem_device *devm_nvmem_register(struct device *dev, 76 const struct nvmem_config *cfg); 77 78 int devm_nvmem_unregister(struct device *dev, struct nvmem_device *nvmem); 79 80 int nvmem_add_cells(struct nvmem_device *nvmem, 81 const struct nvmem_cell_info *info, 82 int ncells); 83 #else 84 85 static inline struct nvmem_device *nvmem_register(const struct nvmem_config *c) 86 { 87 return ERR_PTR(-ENOSYS); 88 } 89 90 static inline int nvmem_unregister(struct nvmem_device *nvmem) 91 { 92 return -ENOSYS; 93 } 94 95 static inline struct nvmem_device * 96 devm_nvmem_register(struct device *dev, const struct nvmem_config *c) 97 { 98 return nvmem_register(c); 99 } 100 101 static inline int 102 devm_nvmem_unregister(struct device *dev, struct nvmem_device *nvmem) 103 { 104 return nvmem_unregister(nvmem); 105 106 } 107 108 static inline int nvmem_add_cells(struct nvmem_device *nvmem, 109 const struct nvmem_cell_info *info, 110 int ncells) 111 { 112 return -ENOSYS; 113 } 114 115 #endif /* CONFIG_NVMEM */ 116 #endif /* ifndef _LINUX_NVMEM_PROVIDER_H */ 117