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SubjectRe: [PATCH] nvmem: core: add NVMEM_SYSFS Kconfig
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Hi Srinivas,

Thanks for the patch,
By default NVMEM_SYSFS should be set true, those whose don't want they
can disable the same.

If we go with disable option, there are chances of eeprom may break in
below case:

if (config->compat) {
rval = nvmem_sysfs_setup_compat(nvmem, config); -> this
will return error as config is disabled.
if (rval)
goto err_device_del;
}

Regards
Gaurav


On 4/15/2019 10:10 PM, Srinivas Kandagatla wrote:
> Many nvmem providers are not very keen on having default sysfs
> nvmem entry, as most of the usecases for them are inside kernel
> itself. And in some cases read/writes to some areas in nvmem are
> restricted and trapped at secure monitor level, so accessing them
> from userspace would result in board reboots.
>
> This patch adds new NVMEM_SYSFS Kconfig to make binary sysfs entry
> an optional one. This provision will give more flexibility to users.
> This patch also moves existing sysfs code to a new file so that its
> not compiled in when its not really required.
>
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> ---
> Documentation/ABI/stable/sysfs-bus-nvmem | 2 +
> drivers/nvmem/Kconfig | 9 +
> drivers/nvmem/Makefile | 3 +
> drivers/nvmem/core.c | 264 +----------------------
> drivers/nvmem/nvmem-sysfs.c | 256 ++++++++++++++++++++++
> drivers/nvmem/nvmem.h | 62 ++++++
> 6 files changed, 336 insertions(+), 260 deletions(-)
> create mode 100644 drivers/nvmem/nvmem-sysfs.c
> create mode 100644 drivers/nvmem/nvmem.h
>
> diff --git a/Documentation/ABI/stable/sysfs-bus-nvmem b/Documentation/ABI/stable/sysfs-bus-nvmem
> index 5923ab4620c5..9ffba8576f7b 100644
> --- a/Documentation/ABI/stable/sysfs-bus-nvmem
> +++ b/Documentation/ABI/stable/sysfs-bus-nvmem
> @@ -6,6 +6,8 @@ Description:
> This file allows user to read/write the raw NVMEM contents.
> Permissions for write to this file depends on the nvmem
> provider configuration.
> + Note: This file is only present if CONFIG_NVMEM_SYSFS
> + is enabled
>
> ex:
> hexdump /sys/bus/nvmem/devices/qfprom0/nvmem
> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> index a90e9a1ebe55..e316811e9c04 100644
> --- a/drivers/nvmem/Kconfig
> +++ b/drivers/nvmem/Kconfig
> @@ -13,6 +13,15 @@ menuconfig NVMEM
>
> if NVMEM
>
> +config NVMEM_SYSFS
> + bool "/sys/bus/nvmem/devices/*/nvmem (sysfs interface)"
> + depends on SYSFS
> + help
> + Say Y here to add a sysfs interface for NVMEM.
> +
> + This interface is mostly used by userspace applications to
> + read/write directly into nvmem.
> +
> config NVMEM_IMX_IIM
> tristate "i.MX IC Identification Module support"
> depends on ARCH_MXC || COMPILE_TEST
> diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
> index 4c7ba12a7005..c1fe4768dfef 100644
> --- a/drivers/nvmem/Makefile
> +++ b/drivers/nvmem/Makefile
> @@ -6,6 +6,9 @@
> obj-$(CONFIG_NVMEM) += nvmem_core.o
> nvmem_core-y := core.o
>
> +obj-$(CONFIG_NVMEM_SYSFS) += nvmem_sysfs.o
> +nvmem_sysfs-y := nvmem-sysfs.o
> +
> # Devices
> obj-$(CONFIG_NVMEM_BCM_OCOTP) += nvmem-bcm-ocotp.o
> nvmem-bcm-ocotp-y := bcm-ocotp.o
> diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
> index 5abebf2128b8..c7892c3da91f 100644
> --- a/drivers/nvmem/core.c
> +++ b/drivers/nvmem/core.c
> @@ -17,27 +17,7 @@
> #include <linux/nvmem-provider.h>
> #include <linux/of.h>
> #include <linux/slab.h>
> -
> -struct nvmem_device {
> - struct module *owner;
> - struct device dev;
> - int stride;
> - int word_size;
> - int id;
> - struct kref refcnt;
> - size_t size;
> - bool read_only;
> - int flags;
> - enum nvmem_type type;
> - struct bin_attribute eeprom;
> - struct device *base_dev;
> - struct list_head cells;
> - nvmem_reg_read_t reg_read;
> - nvmem_reg_write_t reg_write;
> - void *priv;
> -};
> -
> -#define FLAG_COMPAT BIT(0)
> +#include "nvmem.h"
>
> struct nvmem_cell {
> const char *name;
> @@ -61,18 +41,7 @@ static LIST_HEAD(nvmem_lookup_list);
>
> static BLOCKING_NOTIFIER_HEAD(nvmem_notifier);
>
> -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",
> -};
> -
> -#ifdef CONFIG_DEBUG_LOCK_ALLOC
> -static struct lock_class_key eeprom_lock_key;
> -#endif
>
> -#define to_nvmem_device(d) container_of(d, struct nvmem_device, dev)
> static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
> void *val, size_t bytes)
> {
> @@ -91,187 +60,6 @@ static int nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,
> return -EINVAL;
> }
>
> -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 = container_of(kobj, struct device, kobj);
> - nvmem = to_nvmem_device(dev);
> -
> - /* Stop the user from reading */
> - if (pos >= nvmem->size)
> - return 0;
> -
> - if (count < nvmem->word_size)
> - return -EINVAL;
> -
> - if (pos + count > nvmem->size)
> - count = nvmem->size - pos;
> -
> - count = round_down(count, nvmem->word_size);
> -
> - 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 = container_of(kobj, struct device, kobj);
> - nvmem = to_nvmem_device(dev);
> -
> - /* Stop the user from writing */
> - if (pos >= nvmem->size)
> - return -EFBIG;
> -
> - if (count < nvmem->word_size)
> - return -EINVAL;
> -
> - if (pos + count > nvmem->size)
> - count = nvmem->size - pos;
> -
> - count = round_down(count, nvmem->word_size);
> -
> - rc = nvmem_reg_write(nvmem, pos, buf, count);
> -
> - if (rc)
> - return rc;
> -
> - return count;
> -}
> -
> -/* 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_rw_attributes[] = {
> - &bin_attr_rw_nvmem,
> - NULL,
> -};
> -
> -static const struct attribute_group nvmem_bin_rw_group = {
> - .bin_attrs = nvmem_bin_rw_attributes,
> - .attrs = nvmem_attrs,
> -};
> -
> -static const struct attribute_group *nvmem_rw_dev_groups[] = {
> - &nvmem_bin_rw_group,
> - NULL,
> -};
> -
> -/* read only permission */
> -static struct bin_attribute bin_attr_ro_nvmem = {
> - .attr = {
> - .name = "nvmem",
> - .mode = 0444,
> - },
> - .read = bin_attr_nvmem_read,
> -};
> -
> -static struct bin_attribute *nvmem_bin_ro_attributes[] = {
> - &bin_attr_ro_nvmem,
> - NULL,
> -};
> -
> -static const struct attribute_group nvmem_bin_ro_group = {
> - .bin_attrs = nvmem_bin_ro_attributes,
> - .attrs = nvmem_attrs,
> -};
> -
> -static const struct attribute_group *nvmem_ro_dev_groups[] = {
> - &nvmem_bin_ro_group,
> - NULL,
> -};
> -
> -/* default read/write permissions, root only */
> -static struct bin_attribute bin_attr_rw_root_nvmem = {
> - .attr = {
> - .name = "nvmem",
> - .mode = 0600,
> - },
> - .read = bin_attr_nvmem_read,
> - .write = bin_attr_nvmem_write,
> -};
> -
> -static struct bin_attribute *nvmem_bin_rw_root_attributes[] = {
> - &bin_attr_rw_root_nvmem,
> - NULL,
> -};
> -
> -static const struct attribute_group nvmem_bin_rw_root_group = {
> - .bin_attrs = nvmem_bin_rw_root_attributes,
> - .attrs = nvmem_attrs,
> -};
> -
> -static const struct attribute_group *nvmem_rw_root_dev_groups[] = {
> - &nvmem_bin_rw_root_group,
> - NULL,
> -};
> -
> -/* read only permission, root only */
> -static struct bin_attribute bin_attr_ro_root_nvmem = {
> - .attr = {
> - .name = "nvmem",
> - .mode = 0400,
> - },
> - .read = bin_attr_nvmem_read,
> -};
> -
> -static struct bin_attribute *nvmem_bin_ro_root_attributes[] = {
> - &bin_attr_ro_root_nvmem,
> - NULL,
> -};
> -
> -static const struct attribute_group nvmem_bin_ro_root_group = {
> - .bin_attrs = nvmem_bin_ro_root_attributes,
> - .attrs = nvmem_attrs,
> -};
> -
> -static const struct attribute_group *nvmem_ro_root_dev_groups[] = {
> - &nvmem_bin_ro_root_group,
> - NULL,
> -};
> -
> static void nvmem_release(struct device *dev)
> {
> struct nvmem_device *nvmem = to_nvmem_device(dev);
> @@ -422,43 +210,6 @@ static int nvmem_add_cells(struct nvmem_device *nvmem,
> return rval;
> }
>
> -/*
> - * 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_setup_compat(struct nvmem_device *nvmem,
> - const struct nvmem_config *config)
> -{
> - int rval;
> -
> - if (!config->base_dev)
> - return -EINVAL;
> -
> - if (nvmem->read_only)
> - nvmem->eeprom = bin_attr_ro_root_nvmem;
> - else
> - nvmem->eeprom = bin_attr_rw_root_nvmem;
> - nvmem->eeprom.attr.name = "eeprom";
> - 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;
> -}
> -
> /**
> * nvmem_register_notifier() - Register a notifier block for nvmem events.
> *
> @@ -651,14 +402,7 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
> nvmem->read_only = device_property_present(config->dev, "read-only") ||
> config->read_only || !nvmem->reg_write;
>
> - if (config->root_only)
> - nvmem->dev.groups = nvmem->read_only ?
> - nvmem_ro_root_dev_groups :
> - nvmem_rw_root_dev_groups;
> - else
> - nvmem->dev.groups = nvmem->read_only ?
> - nvmem_ro_dev_groups :
> - nvmem_rw_dev_groups;
> + nvmem->dev.groups = nvmem_sysfs_get_groups(nvmem, config);
>
> device_initialize(&nvmem->dev);
>
> @@ -669,7 +413,7 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
> goto err_put_device;
>
> if (config->compat) {
> - rval = nvmem_setup_compat(nvmem, config);
> + rval = nvmem_sysfs_setup_compat(nvmem, config);
> if (rval)
> goto err_device_del;
> }
> @@ -696,7 +440,7 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
> nvmem_device_remove_all_cells(nvmem);
> err_teardown_compat:
> if (config->compat)
> - device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom);
> + nvmem_sysfs_remove_compat(nvmem, config);
> err_device_del:
> device_del(&nvmem->dev);
> err_put_device:
> diff --git a/drivers/nvmem/nvmem-sysfs.c b/drivers/nvmem/nvmem-sysfs.c
> new file mode 100644
> index 000000000000..6f303b91f6e7
> --- /dev/null
> +++ b/drivers/nvmem/nvmem-sysfs.c
> @@ -0,0 +1,256 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2019, Linaro Limited
> + */
> +#include "nvmem.h"
> +
> +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",
> +};
> +
> +#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 = container_of(kobj, struct device, kobj);
> + nvmem = to_nvmem_device(dev);
> +
> + /* Stop the user from reading */
> + if (pos >= nvmem->size)
> + return 0;
> +
> + if (count < nvmem->word_size)
> + return -EINVAL;
> +
> + if (pos + count > nvmem->size)
> + count = nvmem->size - pos;
> +
> + count = round_down(count, nvmem->word_size);
> +
> + rc = nvmem->reg_read(nvmem->priv, 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 = container_of(kobj, struct device, kobj);
> + nvmem = to_nvmem_device(dev);
> +
> + /* Stop the user from writing */
> + if (pos >= nvmem->size)
> + return -EFBIG;
> +
> + if (count < nvmem->word_size)
> + return -EINVAL;
> +
> + if (pos + count > nvmem->size)
> + count = nvmem->size - pos;
> +
> + count = round_down(count, nvmem->word_size);
> +
> + rc = nvmem->reg_write(nvmem->priv, pos, buf, count);
> +
> + if (rc)
> + return rc;
> +
> + return count;
> +}
> +
> +/* 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_rw_attributes[] = {
> + &bin_attr_rw_nvmem,
> + NULL,
> +};
> +
> +static const struct attribute_group nvmem_bin_rw_group = {
> + .bin_attrs = nvmem_bin_rw_attributes,
> + .attrs = nvmem_attrs,
> +};
> +
> +static const struct attribute_group *nvmem_rw_dev_groups[] = {
> + &nvmem_bin_rw_group,
> + NULL,
> +};
> +
> +/* read only permission */
> +static struct bin_attribute bin_attr_ro_nvmem = {
> + .attr = {
> + .name = "nvmem",
> + .mode = 0444,
> + },
> + .read = bin_attr_nvmem_read,
> +};
> +
> +static struct bin_attribute *nvmem_bin_ro_attributes[] = {
> + &bin_attr_ro_nvmem,
> + NULL,
> +};
> +
> +static const struct attribute_group nvmem_bin_ro_group = {
> + .bin_attrs = nvmem_bin_ro_attributes,
> + .attrs = nvmem_attrs,
> +};
> +
> +static const struct attribute_group *nvmem_ro_dev_groups[] = {
> + &nvmem_bin_ro_group,
> + NULL,
> +};
> +
> +/* default read/write permissions, root only */
> +static struct bin_attribute bin_attr_rw_root_nvmem = {
> + .attr = {
> + .name = "nvmem",
> + .mode = 0600,
> + },
> + .read = bin_attr_nvmem_read,
> + .write = bin_attr_nvmem_write,
> +};
> +
> +static struct bin_attribute *nvmem_bin_rw_root_attributes[] = {
> + &bin_attr_rw_root_nvmem,
> + NULL,
> +};
> +
> +static const struct attribute_group nvmem_bin_rw_root_group = {
> + .bin_attrs = nvmem_bin_rw_root_attributes,
> + .attrs = nvmem_attrs,
> +};
> +
> +static const struct attribute_group *nvmem_rw_root_dev_groups[] = {
> + &nvmem_bin_rw_root_group,
> + NULL,
> +};
> +
> +/* read only permission, root only */
> +static struct bin_attribute bin_attr_ro_root_nvmem = {
> + .attr = {
> + .name = "nvmem",
> + .mode = 0400,
> + },
> + .read = bin_attr_nvmem_read,
> +};
> +
> +static struct bin_attribute *nvmem_bin_ro_root_attributes[] = {
> + &bin_attr_ro_root_nvmem,
> + NULL,
> +};
> +
> +static const struct attribute_group nvmem_bin_ro_root_group = {
> + .bin_attrs = nvmem_bin_ro_root_attributes,
> + .attrs = nvmem_attrs,
> +};
> +
> +static const struct attribute_group *nvmem_ro_root_dev_groups[] = {
> + &nvmem_bin_ro_root_group,
> + NULL,
> +};
> +
> +const struct attribute_group **nvmem_sysfs_get_groups(
> + struct nvmem_device *nvmem,
> + const struct nvmem_config *config)
> +{
> + if (config->root_only)
> + return nvmem->read_only ?
> + nvmem_ro_root_dev_groups :
> + nvmem_rw_root_dev_groups;
> +
> + return nvmem->read_only ? nvmem_ro_dev_groups : nvmem_rw_dev_groups;
> +}
> +
> +/*
> + * nvmem_setup_compat() - Create an additional binary entry in
> + * drivers sys directory, to be backwards compatible with the older
> + * drivers/misc/eeprom drivers.
> + */
> +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 (nvmem->read_only)
> + nvmem->eeprom = bin_attr_ro_root_nvmem;
> + else
> + nvmem->eeprom = bin_attr_rw_root_nvmem;
> + nvmem->eeprom.attr.name = "eeprom";
> + 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;
> +}
> +
> +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);
> +}
> diff --git a/drivers/nvmem/nvmem.h b/drivers/nvmem/nvmem.h
> new file mode 100644
> index 000000000000..eb8ed7121fa3
> --- /dev/null
> +++ b/drivers/nvmem/nvmem.h
> @@ -0,0 +1,62 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +#ifndef _DRIVERS_NVMEM_H
> +#define _DRIVERS_NVMEM_H
> +
> +#include <linux/device.h>
> +#include <linux/fs.h>
> +#include <linux/kref.h>
> +#include <linux/list.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/nvmem-provider.h>
> +
> +struct nvmem_device {
> + struct module *owner;
> + struct device dev;
> + int stride;
> + int word_size;
> + int id;
> + struct kref refcnt;
> + size_t size;
> + bool read_only;
> + int flags;
> + enum nvmem_type type;
> + struct bin_attribute eeprom;
> + struct device *base_dev;
> + struct list_head cells;
> + nvmem_reg_read_t reg_read;
> + nvmem_reg_write_t reg_write;
> + void *priv;
> +};
> +
> +#define to_nvmem_device(d) container_of(d, struct nvmem_device, dev)
> +#define FLAG_COMPAT BIT(0)
> +
> +#ifdef CONFIG_NVMEM_SYSFS
> +const struct attribute_group **nvmem_sysfs_get_groups(
> + struct nvmem_device *nvmem,
> + const struct nvmem_config *config);
> +int nvmem_sysfs_setup_compat(struct nvmem_device *nvmem,
> + const struct nvmem_config *config);
> +void nvmem_sysfs_remove_compat(struct nvmem_device *nvmem,
> + const struct nvmem_config *config);
> +#else
> +static inline const struct attribute_group **nvmem_sysfs_get_groups(
> + struct nvmem_device *nvmem,
> + const struct nvmem_config *config)
> +{
> + return NULL;
> +}
> +
> +static inline int nvmem_sysfs_setup_compat(struct nvmem_device *nvmem,
> + const struct nvmem_config *config)
> +{
> + return -ENOSYS;
> +}
> +static inline void nvmem_sysfs_remove_compat(struct nvmem_device *nvmem,
> + const struct nvmem_config *config)
> +{
> +}
> +#endif /* CONFIG_NVMEM_SYSFS */
> +
> +#endif /* _DRIVERS_NVMEM_H */

--
Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center,
Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.

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