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core.c
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// SPDX-License-Identifier: GPL-2.0
/*
* nvmem framework core.
*
* Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
* Copyright (C) 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
*/
#include <linux/device.h>
#include <linux/export.h>
#include <linux/fs.h>
#include <linux/idr.h>
#include <linux/init.h>
#include <linux/kref.h>
#include <linux/module.h>
#include <linux/nvmem-consumer.h>
#include <linux/nvmem-provider.h>
#include <linux/gpio/consumer.h>
#include <linux/of.h>
#include <linux/slab.h>
#include "internals.h"
#define to_nvmem_device(d) container_of(d, struct nvmem_device, dev)
#define FLAG_COMPAT BIT(0)
struct nvmem_cell_entry {
const char *name;
int offset;
size_t raw_len;
int bytes;
int bit_offset;
int nbits;
nvmem_cell_post_process_t read_post_process;
void *priv;
struct device_node *np;
struct nvmem_device *nvmem;
struct list_head node;
};
struct nvmem_cell {
struct nvmem_cell_entry *entry;
const char *id;
int index;
};
static DEFINE_MUTEX(nvmem_mutex);
static DEFINE_IDA(nvmem_ida);
static DEFINE_MUTEX(nvmem_cell_mutex);
static LIST_HEAD(nvmem_cell_tables);
static DEFINE_MUTEX(nvmem_lookup_mutex);
static LIST_HEAD(nvmem_lookup_list);
static BLOCKING_NOTIFIER_HEAD(nvmem_notifier);
static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
if (nvmem->reg_read)
return nvmem->reg_read(nvmem->priv, offset, val, bytes);
return -EINVAL;
}
static int __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
int ret;
if (nvmem->reg_write) {
gpiod_set_value_cansleep(nvmem->wp_gpio, 0);
ret = nvmem->reg_write(nvmem->priv, offset, val, bytes);
gpiod_set_value_cansleep(nvmem->wp_gpio, 1);
return ret;
}
return -EINVAL;
}
static int nvmem_access_with_keepouts(struct nvmem_device *nvmem,
unsigned int offset, void *val,
size_t bytes, int write)
{
unsigned int end = offset + bytes;
unsigned int kend, ksize;
const struct nvmem_keepout *keepout = nvmem->keepout;
const struct nvmem_keepout *keepoutend = keepout + nvmem->nkeepout;
int rc;
/*
* Skip all keepouts before the range being accessed.
* Keepouts are sorted.
*/
while ((keepout < keepoutend) && (keepout->end <= offset))
keepout++;
while ((offset < end) && (keepout < keepoutend)) {
/* Access the valid portion before the keepout. */
if (offset < keepout->start) {
kend = min(end, keepout->start);
ksize = kend - offset;
if (write)
rc = __nvmem_reg_write(nvmem, offset, val, ksize);
else
rc = __nvmem_reg_read(nvmem, offset, val, ksize);
if (rc)
return rc;
offset += ksize;
val += ksize;
}
/*
* Now we're aligned to the start of this keepout zone. Go
* through it.
*/
kend = min(end, keepout->end);
ksize = kend - offset;
if (!write)
memset(val, keepout->value, ksize);
val += ksize;
offset += ksize;
keepout++;
}
/*
* If we ran out of keepouts but there's still stuff to do, send it
* down directly
*/
if (offset < end) {
ksize = end - offset;
if (write)
return __nvmem_reg_write(nvmem, offset, val, ksize);
else
return __nvmem_reg_read(nvmem, offset, val, ksize);
}
return 0;
}
static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
if (!nvmem->nkeepout)
return __nvmem_reg_read(nvmem, offset, val, bytes);
return nvmem_access_with_keepouts(nvmem, offset, val, bytes, false);
}
static int nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
if (!nvmem->nkeepout)
return __nvmem_reg_write(nvmem, offset, val, bytes);
return nvmem_access_with_keepouts(nvmem, offset, val, bytes, true);
}
#ifdef CONFIG_NVMEM_SYSFS
static const char * const nvmem_type_str[] = {
[NVMEM_TYPE_UNKNOWN] = "Unknown",
[NVMEM_TYPE_EEPROM] = "EEPROM",
[NVMEM_TYPE_OTP] = "OTP",
[NVMEM_TYPE_BATTERY_BACKED] = "Battery backed",
[NVMEM_TYPE_FRAM] = "FRAM",
};
#ifdef CONFIG_DEBUG_LOCK_ALLOC
static struct lock_class_key eeprom_lock_key;
#endif
static ssize_t type_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nvmem_device *nvmem = to_nvmem_device(dev);
return sprintf(buf, "%s\n", nvmem_type_str[nvmem->type]);
}
static DEVICE_ATTR_RO(type);
static struct attribute *nvmem_attrs[] = {
&dev_attr_type.attr,
NULL,
};
static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr, char *buf,
loff_t pos, size_t count)
{
struct device *dev;
struct nvmem_device *nvmem;
int rc;
if (attr->private)
dev = attr->private;
else
dev = kobj_to_dev(kobj);
nvmem = to_nvmem_device(dev);
/* Stop the user from reading */
if (pos >= nvmem->size)
return 0;
if (!IS_ALIGNED(pos, nvmem->stride))
return -EINVAL;
if (count < nvmem->word_size)
return -EINVAL;
if (pos + count > nvmem->size)
count = nvmem->size - pos;
count = round_down(count, nvmem->word_size);
if (!nvmem->reg_read)
return -EPERM;
rc = nvmem_reg_read(nvmem, pos, buf, count);
if (rc)
return rc;
return count;
}
static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr, char *buf,
loff_t pos, size_t count)
{
struct device *dev;
struct nvmem_device *nvmem;
int rc;
if (attr->private)
dev = attr->private;
else
dev = kobj_to_dev(kobj);
nvmem = to_nvmem_device(dev);
/* Stop the user from writing */
if (pos >= nvmem->size)
return -EFBIG;
if (!IS_ALIGNED(pos, nvmem->stride))
return -EINVAL;
if (count < nvmem->word_size)
return -EINVAL;
if (pos + count > nvmem->size)
count = nvmem->size - pos;
count = round_down(count, nvmem->word_size);
if (!nvmem->reg_write)
return -EPERM;
rc = nvmem_reg_write(nvmem, pos, buf, count);
if (rc)
return rc;
return count;
}
static umode_t nvmem_bin_attr_get_umode(struct nvmem_device *nvmem)
{
umode_t mode = 0400;
if (!nvmem->root_only)
mode |= 0044;
if (!nvmem->read_only)
mode |= 0200;
if (!nvmem->reg_write)
mode &= ~0200;
if (!nvmem->reg_read)
mode &= ~0444;
return mode;
}
static umode_t nvmem_bin_attr_is_visible(struct kobject *kobj,
struct bin_attribute *attr, int i)
{
struct device *dev = kobj_to_dev(kobj);
struct nvmem_device *nvmem = to_nvmem_device(dev);
attr->size = nvmem->size;
return nvmem_bin_attr_get_umode(nvmem);
}
static struct nvmem_cell *nvmem_create_cell(struct nvmem_cell_entry *entry,
const char *id, int index);
static ssize_t nvmem_cell_attr_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr, char *buf,
loff_t pos, size_t count)
{
struct nvmem_cell_entry *entry;
struct nvmem_cell *cell = NULL;
size_t cell_sz, read_len;
void *content;
entry = attr->private;
cell = nvmem_create_cell(entry, entry->name, 0);
if (IS_ERR(cell))
return PTR_ERR(cell);
if (!cell)
return -EINVAL;
content = nvmem_cell_read(cell, &cell_sz);
if (IS_ERR(content)) {
read_len = PTR_ERR(content);
goto destroy_cell;
}
read_len = min_t(unsigned int, cell_sz - pos, count);
memcpy(buf, content + pos, read_len);
kfree(content);
destroy_cell:
kfree_const(cell->id);
kfree(cell);
return read_len;
}
/* default read/write permissions */
static struct bin_attribute bin_attr_rw_nvmem = {
.attr = {
.name = "nvmem",
.mode = 0644,
},
.read = bin_attr_nvmem_read,
.write = bin_attr_nvmem_write,
};
static struct bin_attribute *nvmem_bin_attributes[] = {
&bin_attr_rw_nvmem,
NULL,
};
static const struct attribute_group nvmem_bin_group = {
.bin_attrs = nvmem_bin_attributes,
.attrs = nvmem_attrs,
.is_bin_visible = nvmem_bin_attr_is_visible,
};
/* Cell attributes will be dynamically allocated */
static struct attribute_group nvmem_cells_group = {
.name = "cells",
};
static const struct attribute_group *nvmem_dev_groups[] = {
&nvmem_bin_group,
NULL,
};
static const struct attribute_group *nvmem_cells_groups[] = {
&nvmem_cells_group,
NULL,
};
static struct bin_attribute bin_attr_nvmem_eeprom_compat = {
.attr = {
.name = "eeprom",
},
.read = bin_attr_nvmem_read,
.write = bin_attr_nvmem_write,
};
/*
* nvmem_setup_compat() - Create an additional binary entry in
* drivers sys directory, to be backwards compatible with the older
* drivers/misc/eeprom drivers.
*/
static int nvmem_sysfs_setup_compat(struct nvmem_device *nvmem,
const struct nvmem_config *config)
{
int rval;
if (!config->compat)
return 0;
if (!config->base_dev)
return -EINVAL;
if (config->type == NVMEM_TYPE_FRAM)
bin_attr_nvmem_eeprom_compat.attr.name = "fram";
nvmem->eeprom = bin_attr_nvmem_eeprom_compat;
nvmem->eeprom.attr.mode = nvmem_bin_attr_get_umode(nvmem);
nvmem->eeprom.size = nvmem->size;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
nvmem->eeprom.attr.key = &eeprom_lock_key;
#endif
nvmem->eeprom.private = &nvmem->dev;
nvmem->base_dev = config->base_dev;
rval = device_create_bin_file(nvmem->base_dev, &nvmem->eeprom);
if (rval) {
dev_err(&nvmem->dev,
"Failed to create eeprom binary file %d\n", rval);
return rval;
}
nvmem->flags |= FLAG_COMPAT;
return 0;
}
static void nvmem_sysfs_remove_compat(struct nvmem_device *nvmem,
const struct nvmem_config *config)
{
if (config->compat)
device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom);
}
static int nvmem_populate_sysfs_cells(struct nvmem_device *nvmem)
{
struct bin_attribute **cells_attrs, *attrs;
struct nvmem_cell_entry *entry;
unsigned int ncells = 0, i = 0;
int ret = 0;
mutex_lock(&nvmem_mutex);
if (list_empty(&nvmem->cells) || nvmem->sysfs_cells_populated) {
nvmem_cells_group.bin_attrs = NULL;
goto unlock_mutex;
}
/* Allocate an array of attributes with a sentinel */
ncells = list_count_nodes(&nvmem->cells);
cells_attrs = devm_kcalloc(&nvmem->dev, ncells + 1,
sizeof(struct bin_attribute *), GFP_KERNEL);
if (!cells_attrs) {
ret = -ENOMEM;
goto unlock_mutex;
}
attrs = devm_kcalloc(&nvmem->dev, ncells, sizeof(struct bin_attribute), GFP_KERNEL);
if (!attrs) {
ret = -ENOMEM;
goto unlock_mutex;
}
/* Initialize each attribute to take the name and size of the cell */
list_for_each_entry(entry, &nvmem->cells, node) {
sysfs_bin_attr_init(&attrs[i]);
attrs[i].attr.name = devm_kasprintf(&nvmem->dev, GFP_KERNEL,
"%s@%x,%x", entry->name,
entry->offset,
entry->bit_offset);
attrs[i].attr.mode = 0444;
attrs[i].size = entry->bytes;
attrs[i].read = &nvmem_cell_attr_read;
attrs[i].private = entry;
if (!attrs[i].attr.name) {
ret = -ENOMEM;
goto unlock_mutex;
}
cells_attrs[i] = &attrs[i];
i++;
}
nvmem_cells_group.bin_attrs = cells_attrs;
ret = devm_device_add_groups(&nvmem->dev, nvmem_cells_groups);
if (ret)
goto unlock_mutex;
nvmem->sysfs_cells_populated = true;
unlock_mutex:
mutex_unlock(&nvmem_mutex);
return ret;
}
#else /* CONFIG_NVMEM_SYSFS */
static int nvmem_sysfs_setup_compat(struct nvmem_device *nvmem,
const struct nvmem_config *config)
{
return -ENOSYS;
}
static void nvmem_sysfs_remove_compat(struct nvmem_device *nvmem,
const struct nvmem_config *config)
{
}
#endif /* CONFIG_NVMEM_SYSFS */
static void nvmem_release(struct device *dev)
{
struct nvmem_device *nvmem = to_nvmem_device(dev);
ida_free(&nvmem_ida, nvmem->id);
gpiod_put(nvmem->wp_gpio);
kfree(nvmem);
}
static const struct device_type nvmem_provider_type = {
.release = nvmem_release,
};
static struct bus_type nvmem_bus_type = {
.name = "nvmem",
};
static void nvmem_cell_entry_drop(struct nvmem_cell_entry *cell)
{
blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_REMOVE, cell);
mutex_lock(&nvmem_mutex);
list_del(&cell->node);
mutex_unlock(&nvmem_mutex);
of_node_put(cell->np);
kfree_const(cell->name);
kfree(cell);
}
static void nvmem_device_remove_all_cells(const struct nvmem_device *nvmem)
{
struct nvmem_cell_entry *cell, *p;
list_for_each_entry_safe(cell, p, &nvmem->cells, node)
nvmem_cell_entry_drop(cell);
}
static void nvmem_cell_entry_add(struct nvmem_cell_entry *cell)
{
mutex_lock(&nvmem_mutex);
list_add_tail(&cell->node, &cell->nvmem->cells);
mutex_unlock(&nvmem_mutex);
blocking_notifier_call_chain(&nvmem_notifier, NVMEM_CELL_ADD, cell);
}
static int nvmem_cell_info_to_nvmem_cell_entry_nodup(struct nvmem_device *nvmem,
const struct nvmem_cell_info *info,
struct nvmem_cell_entry *cell)
{
cell->nvmem = nvmem;
cell->offset = info->offset;
cell->raw_len = info->raw_len ?: info->bytes;
cell->bytes = info->bytes;
cell->name = info->name;
cell->read_post_process = info->read_post_process;
cell->priv = info->priv;
cell->bit_offset = info->bit_offset;
cell->nbits = info->nbits;
cell->np = info->np;
if (cell->nbits)
cell->bytes = DIV_ROUND_UP(cell->nbits + cell->bit_offset,
BITS_PER_BYTE);
if (!IS_ALIGNED(cell->offset, nvmem->stride)) {
dev_err(&nvmem->dev,
"cell %s unaligned to nvmem stride %d\n",
cell->name ?: "<unknown>", nvmem->stride);
return -EINVAL;
}
return 0;
}
static int nvmem_cell_info_to_nvmem_cell_entry(struct nvmem_device *nvmem,
const struct nvmem_cell_info *info,
struct nvmem_cell_entry *cell)
{
int err;
err = nvmem_cell_info_to_nvmem_cell_entry_nodup(nvmem, info, cell);
if (err)
return err;
cell->name = kstrdup_const(info->name, GFP_KERNEL);
if (!cell->name)
return -ENOMEM;
return 0;
}
/**
* nvmem_add_one_cell() - Add one cell information to an nvmem device
*
* @nvmem: nvmem device to add cells to.
* @info: nvmem cell info to add to the device
*
* Return: 0 or negative error code on failure.
*/
int nvmem_add_one_cell(struct nvmem_device *nvmem,
const struct nvmem_cell_info *info)
{
struct nvmem_cell_entry *cell;
int rval;
cell = kzalloc(sizeof(*cell), GFP_KERNEL);
if (!cell)
return -ENOMEM;
rval = nvmem_cell_info_to_nvmem_cell_entry(nvmem, info, cell);
if (rval) {
kfree(cell);
return rval;
}
nvmem_cell_entry_add(cell);
return 0;
}
EXPORT_SYMBOL_GPL(nvmem_add_one_cell);
/**
* nvmem_add_cells() - Add cell information to an nvmem device
*
* @nvmem: nvmem device to add cells to.
* @info: nvmem cell info to add to the device
* @ncells: number of cells in info
*
* Return: 0 or negative error code on failure.
*/
static int nvmem_add_cells(struct nvmem_device *nvmem,
const struct nvmem_cell_info *info,
int ncells)
{
int i, rval;
for (i = 0; i < ncells; i++) {
rval = nvmem_add_one_cell(nvmem, &info[i]);
if (rval)
return rval;
}
return 0;
}
/**
* nvmem_register_notifier() - Register a notifier block for nvmem events.
*
* @nb: notifier block to be called on nvmem events.
*
* Return: 0 on success, negative error number on failure.
*/
int nvmem_register_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&nvmem_notifier, nb);
}
EXPORT_SYMBOL_GPL(nvmem_register_notifier);
/**
* nvmem_unregister_notifier() - Unregister a notifier block for nvmem events.
*
* @nb: notifier block to be unregistered.
*
* Return: 0 on success, negative error number on failure.
*/
int nvmem_unregister_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&nvmem_notifier, nb);
}
EXPORT_SYMBOL_GPL(nvmem_unregister_notifier);
static int nvmem_add_cells_from_table(struct nvmem_device *nvmem)
{
const struct nvmem_cell_info *info;
struct nvmem_cell_table *table;
struct nvmem_cell_entry *cell;
int rval = 0, i;
mutex_lock(&nvmem_cell_mutex);
list_for_each_entry(table, &nvmem_cell_tables, node) {
if (strcmp(nvmem_dev_name(nvmem), table->nvmem_name) == 0) {
for (i = 0; i < table->ncells; i++) {
info = &table->cells[i];
cell = kzalloc(sizeof(*cell), GFP_KERNEL);
if (!cell) {
rval = -ENOMEM;
goto out;
}
rval = nvmem_cell_info_to_nvmem_cell_entry(nvmem, info, cell);
if (rval) {
kfree(cell);
goto out;
}
nvmem_cell_entry_add(cell);
}
}
}
out:
mutex_unlock(&nvmem_cell_mutex);
return rval;
}
static struct nvmem_cell_entry *
nvmem_find_cell_entry_by_name(struct nvmem_device *nvmem, const char *cell_id)
{
struct nvmem_cell_entry *iter, *cell = NULL;
mutex_lock(&nvmem_mutex);
list_for_each_entry(iter, &nvmem->cells, node) {
if (strcmp(cell_id, iter->name) == 0) {
cell = iter;
break;
}
}
mutex_unlock(&nvmem_mutex);
return cell;
}
static int nvmem_validate_keepouts(struct nvmem_device *nvmem)
{
unsigned int cur = 0;
const struct nvmem_keepout *keepout = nvmem->keepout;
const struct nvmem_keepout *keepoutend = keepout + nvmem->nkeepout;
while (keepout < keepoutend) {
/* Ensure keepouts are sorted and don't overlap. */
if (keepout->start < cur) {
dev_err(&nvmem->dev,
"Keepout regions aren't sorted or overlap.\n");
return -ERANGE;
}
if (keepout->end < keepout->start) {
dev_err(&nvmem->dev,
"Invalid keepout region.\n");
return -EINVAL;
}
/*
* Validate keepouts (and holes between) don't violate
* word_size constraints.
*/
if ((keepout->end - keepout->start < nvmem->word_size) ||
((keepout->start != cur) &&
(keepout->start - cur < nvmem->word_size))) {
dev_err(&nvmem->dev,
"Keepout regions violate word_size constraints.\n");
return -ERANGE;
}
/* Validate keepouts don't violate stride (alignment). */
if (!IS_ALIGNED(keepout->start, nvmem->stride) ||
!IS_ALIGNED(keepout->end, nvmem->stride)) {
dev_err(&nvmem->dev,
"Keepout regions violate stride.\n");
return -EINVAL;
}
cur = keepout->end;
keepout++;
}
return 0;
}
static int nvmem_add_cells_from_dt(struct nvmem_device *nvmem, struct device_node *np)
{
struct device *dev = &nvmem->dev;
struct device_node *child;
const __be32 *addr;
int len, ret;
for_each_child_of_node(np, child) {
struct nvmem_cell_info info = {0};
addr = of_get_property(child, "reg", &len);
if (!addr)
continue;
if (len < 2 * sizeof(u32)) {
dev_err(dev, "nvmem: invalid reg on %pOF\n", child);
of_node_put(child);
return -EINVAL;
}
info.offset = be32_to_cpup(addr++);
info.bytes = be32_to_cpup(addr);
info.name = kasprintf(GFP_KERNEL, "%pOFn", child);
addr = of_get_property(child, "bits", &len);
if (addr && len == (2 * sizeof(u32))) {
info.bit_offset = be32_to_cpup(addr++);
info.nbits = be32_to_cpup(addr);
if (info.bit_offset >= BITS_PER_BYTE || info.nbits < 1) {
dev_err(dev, "nvmem: invalid bits on %pOF\n", child);
of_node_put(child);
return -EINVAL;
}
}
info.np = of_node_get(child);
if (nvmem->fixup_dt_cell_info)
nvmem->fixup_dt_cell_info(nvmem, &info);
ret = nvmem_add_one_cell(nvmem, &info);
kfree(info.name);
if (ret) {
of_node_put(child);
return ret;
}
}
return 0;
}
static int nvmem_add_cells_from_legacy_of(struct nvmem_device *nvmem)
{
return nvmem_add_cells_from_dt(nvmem, nvmem->dev.of_node);
}
static int nvmem_add_cells_from_fixed_layout(struct nvmem_device *nvmem)
{
struct device_node *layout_np;
int err = 0;
layout_np = of_nvmem_layout_get_container(nvmem);
if (!layout_np)
return 0;
if (of_device_is_compatible(layout_np, "fixed-layout"))
err = nvmem_add_cells_from_dt(nvmem, layout_np);
of_node_put(layout_np);
return err;
}
int nvmem_layout_register(struct nvmem_layout *layout)
{
int ret;
if (!layout->add_cells)
return -EINVAL;
/* Populate the cells */
ret = layout->add_cells(layout);
if (ret)
return ret;
#ifdef CONFIG_NVMEM_SYSFS
ret = nvmem_populate_sysfs_cells(layout->nvmem);
if (ret) {
nvmem_device_remove_all_cells(layout->nvmem);
return ret;
}
#endif
return 0;
}
EXPORT_SYMBOL_GPL(nvmem_layout_register);
void nvmem_layout_unregister(struct nvmem_layout *layout)
{
/* Keep the API even with an empty stub in case we need it later */
}
EXPORT_SYMBOL_GPL(nvmem_layout_unregister);
/**
* nvmem_register() - Register a nvmem device for given nvmem_config.
* Also creates a binary entry in /sys/bus/nvmem/devices/dev-name/nvmem
*
* @config: nvmem device configuration with which nvmem device is created.
*
* Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device
* on success.
*/
struct nvmem_device *nvmem_register(const struct nvmem_config *config)
{
struct nvmem_device *nvmem;
int rval;
if (!config->dev)
return ERR_PTR(-EINVAL);
if (!config->reg_read && !config->reg_write)
return ERR_PTR(-EINVAL);
nvmem = kzalloc(sizeof(*nvmem), GFP_KERNEL);
if (!nvmem)
return ERR_PTR(-ENOMEM);
rval = ida_alloc(&nvmem_ida, GFP_KERNEL);
if (rval < 0) {
kfree(nvmem);
return ERR_PTR(rval);
}
nvmem->id = rval;
nvmem->dev.type = &nvmem_provider_type;
nvmem->dev.bus = &nvmem_bus_type;
nvmem->dev.parent = config->dev;
device_initialize(&nvmem->dev);
if (!config->ignore_wp)
nvmem->wp_gpio = gpiod_get_optional(config->dev, "wp",
GPIOD_OUT_HIGH);
if (IS_ERR(nvmem->wp_gpio)) {
rval = PTR_ERR(nvmem->wp_gpio);
nvmem->wp_gpio = NULL;
goto err_put_device;
}
kref_init(&nvmem->refcnt);
INIT_LIST_HEAD(&nvmem->cells);
nvmem->fixup_dt_cell_info = config->fixup_dt_cell_info;
nvmem->owner = config->owner;
if (!nvmem->owner && config->dev->driver)
nvmem->owner = config->dev->driver->owner;
nvmem->stride = config->stride ?: 1;
nvmem->word_size = config->word_size ?: 1;
nvmem->size = config->size;
nvmem->root_only = config->root_only;
nvmem->priv = config->priv;
nvmem->type = config->type;
nvmem->reg_read = config->reg_read;
nvmem->reg_write = config->reg_write;
nvmem->keepout = config->keepout;
nvmem->nkeepout = config->nkeepout;
if (config->of_node)
nvmem->dev.of_node = config->of_node;
else
nvmem->dev.of_node = config->dev->of_node;
switch (config->id) {
case NVMEM_DEVID_NONE:
rval = dev_set_name(&nvmem->dev, "%s", config->name);
break;
case NVMEM_DEVID_AUTO:
rval = dev_set_name(&nvmem->dev, "%s%d", config->name, nvmem->id);
break;
default:
rval = dev_set_name(&nvmem->dev, "%s%d",
config->name ? : "nvmem",
config->name ? config->id : nvmem->id);
break;
}
if (rval)
goto err_put_device;
nvmem->read_only = device_property_present(config->dev, "read-only") ||
config->read_only || !nvmem->reg_write;
#ifdef CONFIG_NVMEM_SYSFS
nvmem->dev.groups = nvmem_dev_groups;
#endif
if (nvmem->nkeepout) {
rval = nvmem_validate_keepouts(nvmem);
if (rval)
goto err_put_device;
}
if (config->compat) {
rval = nvmem_sysfs_setup_compat(nvmem, config);
if (rval)
goto err_put_device;
}
if (config->cells) {
rval = nvmem_add_cells(nvmem, config->cells, config->ncells);
if (rval)
goto err_remove_cells;
}
rval = nvmem_add_cells_from_table(nvmem);
if (rval)
goto err_remove_cells;