nvmem: core: add root_only member to nvmem device struct

As we are planning to move to use sysfs is_bin_visible callback,
having root_only as part of nvmem_device will help decide correct
permissions.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200325122116.15096-2-srinivas.kandagatla@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/nvmem/core.c

@@ -377,6 +377,7 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
 	nvmem->dev.type = &nvmem_provider_type;
 	nvmem->dev.bus = &nvmem_bus_type;
 	nvmem->dev.parent = config->dev;
+	nvmem->root_only = config->root_only;
 	nvmem->priv = config->priv;
 	nvmem->type = config->type;
 	nvmem->reg_read = config->reg_read;

drivers/nvmem/nvmem.h

@@ -20,6 +20,7 @@ struct nvmem_device {
 	struct kref		refcnt;
 	size_t			size;
 	bool			read_only;
+	bool			root_only;
 	int			flags;
 	enum nvmem_type		type;
 	struct bin_attribute	eeprom;