diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index a4c75a28c839..0ff2d4d81bb0 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -344,6 +344,7 @@ Code  Seq#    Include File                                           Comments
 0xB5  00-0F  uapi/linux/rpmsg.h                                      <mailto:linux-remoteproc@vger.kernel.org>
 0xB6  all    linux/fpga-dfl.h
 0xB7  all    uapi/linux/remoteproc_cdev.h                            <mailto:linux-remoteproc@vger.kernel.org>
+0xB8  80-8F  uapi/linux/rpmb.h                                       <mailto:linux-mmc@vger.kernel.org>
 0xC0  00-0F  linux/usb/iowarrior.h
 0xCA  00-0F  uapi/misc/cxl.h
 0xCA  10-2F  uapi/misc/ocxl.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 076f3983526c..c60b41b6e6bd 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15374,6 +15374,7 @@ M:	?
 L:	linux-kernel@vger.kernel.org
 S:	Supported
 F:	drivers/char/rpmb/*
+F:	include/uapi/linux/rpmb.h
 F:	include/linux/rpmb.h
 
 RTL2830 MEDIA DRIVER
diff --git a/drivers/char/rpmb/Kconfig b/drivers/char/rpmb/Kconfig
index 431c2823cf70..9068664a399a 100644
--- a/drivers/char/rpmb/Kconfig
+++ b/drivers/char/rpmb/Kconfig
@@ -9,3 +9,10 @@ config RPMB
 	  access RPMB partition.
 
 	  If unsure, select N.
+
+config RPMB_INTF_DEV
+	bool "RPMB character device interface /dev/rpmbN"
+	depends on RPMB && KEYS
+	help
+	  Say yes here if you want to access RPMB from user space
+	  via character device interface /dev/rpmb%d
diff --git a/drivers/char/rpmb/Makefile b/drivers/char/rpmb/Makefile
index 24d4752a9a53..f54b3f30514b 100644
--- a/drivers/char/rpmb/Makefile
+++ b/drivers/char/rpmb/Makefile
@@ -3,5 +3,6 @@
 
 obj-$(CONFIG_RPMB) += rpmb.o
 rpmb-objs += core.o
+rpmb-$(CONFIG_RPMB_INTF_DEV) += cdev.o
 
 ccflags-y += -D__CHECK_ENDIAN__
diff --git a/drivers/char/rpmb/cdev.c b/drivers/char/rpmb/cdev.c
new file mode 100644
index 000000000000..55f66720fd03
--- /dev/null
+++ b/drivers/char/rpmb/cdev.c
@@ -0,0 +1,246 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright(c) 2015 - 2019 Intel Corporation.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/compat.h>
+#include <linux/slab.h>
+#include <linux/capability.h>
+
+#include <linux/rpmb.h>
+
+#include "rpmb-cdev.h"
+
+static dev_t rpmb_devt;
+#define RPMB_MAX_DEVS  MINORMASK
+
+#define RPMB_DEV_OPEN    0  /** single open bit (position) */
+
+/**
+ * rpmb_open - the open function
+ *
+ * @inode: pointer to inode structure
+ * @fp: pointer to file structure
+ *
+ * Return: 0 on success, <0 on error
+ */
+static int rpmb_open(struct inode *inode, struct file *fp)
+{
+	struct rpmb_dev *rdev;
+
+	rdev = container_of(inode->i_cdev, struct rpmb_dev, cdev);
+	if (!rdev)
+		return -ENODEV;
+
+	/* the rpmb is single open! */
+	if (test_and_set_bit(RPMB_DEV_OPEN, &rdev->status))
+		return -EBUSY;
+
+	mutex_lock(&rdev->lock);
+
+	fp->private_data = rdev;
+
+	mutex_unlock(&rdev->lock);
+
+	return nonseekable_open(inode, fp);
+}
+
+/**
+ * rpmb_release - the cdev release function
+ *
+ * @inode: pointer to inode structure
+ * @fp: pointer to file structure
+ *
+ * Return: 0 always.
+ */
+static int rpmb_release(struct inode *inode, struct file *fp)
+{
+	struct rpmb_dev *rdev = fp->private_data;
+
+	clear_bit(RPMB_DEV_OPEN, &rdev->status);
+
+	return 0;
+}
+
+static long rpmb_ioctl_ver_cmd(struct rpmb_dev *rdev,
+			       struct rpmb_ioc_ver_cmd __user *ptr)
+{
+	struct rpmb_ioc_ver_cmd ver = {
+		.api_version = RPMB_API_VERSION,
+	};
+
+	return copy_to_user(ptr, &ver, sizeof(ver)) ? -EFAULT : 0;
+}
+
+static long rpmb_ioctl_cap_cmd(struct rpmb_dev *rdev,
+			       struct rpmb_ioc_cap_cmd __user *ptr)
+{
+	struct rpmb_ioc_cap_cmd cap;
+
+	cap.target      = rdev->target;
+	cap.block_size  = rdev->ops->block_size;
+	cap.wr_cnt_max  = rdev->ops->wr_cnt_max;
+	cap.rd_cnt_max  = rdev->ops->rd_cnt_max;
+	cap.auth_method = rdev->ops->auth_method;
+	cap.capacity    = rpmb_get_capacity(rdev);
+	cap.reserved    = 0;
+
+	return copy_to_user(ptr, &cap, sizeof(cap)) ? -EFAULT : 0;
+}
+
+static long rpmb_ioctl_pkey_cmd(struct rpmb_dev *rdev, key_serial_t __user *k)
+{
+	key_serial_t keyid;
+
+	if (get_user(keyid, k))
+		return -EFAULT;
+	else
+		return rpmb_program_key(rdev, keyid);
+}
+
+static long rpmb_ioctl_counter_cmd(struct rpmb_dev *rdev, int __user *ptr)
+{
+	int count = rpmb_get_write_count(rdev);
+
+	if (count > 0)
+		return put_user(count, ptr);
+	else
+		return count;
+}
+
+static long rpmb_ioctl_wblocks_cmd(struct rpmb_dev *rdev,
+				   struct rpmb_ioc_blocks_cmd __user *ptr)
+{
+	struct rpmb_ioc_blocks_cmd wblocks;
+	int sz;
+	long ret;
+	u8 *data;
+
+	if (copy_from_user(&wblocks, ptr, sizeof(struct rpmb_ioc_blocks_cmd)))
+		return -EFAULT;
+
+	/* Don't write more blocks device supports */
+	if (wblocks.count > rdev->ops->wr_cnt_max)
+		return -EINVAL;
+
+	sz = wblocks.count * 256;
+	data = kmalloc(sz, GFP_KERNEL);
+
+	if (!data)
+		return -ENOMEM;
+
+	if (copy_from_user(data, wblocks.data, sz))
+		ret = -EFAULT;
+	else
+		ret = rpmb_write_blocks(rdev, wblocks.key, wblocks.addr, wblocks.count, data);
+
+	kfree(data);
+	return ret;
+}
+
+static long rpmb_ioctl_rblocks_cmd(struct rpmb_dev *rdev,
+				   struct rpmb_ioc_blocks_cmd __user *ptr)
+{
+	struct rpmb_ioc_blocks_cmd rblocks;
+	int sz;
+	long ret;
+	u8 *data;
+
+	if (copy_from_user(&rblocks, ptr, sizeof(struct rpmb_ioc_blocks_cmd)))
+		return -EFAULT;
+
+	if (rblocks.count > rdev->ops->rd_cnt_max)
+		return -EINVAL;
+
+	sz = rblocks.count * 256;
+	data = kmalloc(sz, GFP_KERNEL);
+
+	if (!data)
+		return -ENOMEM;
+
+	ret = rpmb_read_blocks(rdev, rblocks.addr, rblocks.count, data);
+
+	if (ret == 0)
+		ret = copy_to_user(rblocks.data, data, sz);
+
+	kfree(data);
+	return ret;
+}
+
+/**
+ * rpmb_ioctl - rpmb ioctl dispatcher
+ *
+ * @fp: a file pointer
+ * @cmd: ioctl command RPMB_IOC_SEQ_CMD RPMB_IOC_VER_CMD RPMB_IOC_CAP_CMD
+ * @arg: ioctl data: rpmb_ioc_ver_cmd rpmb_ioc_cap_cmd pmb_ioc_seq_cmd
+ *
+ * Return: 0 on success; < 0 on error
+ */
+static long rpmb_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+	struct rpmb_dev *rdev = fp->private_data;
+	void __user *ptr = (void __user *)arg;
+
+	switch (cmd) {
+	case RPMB_IOC_VER_CMD:
+		return rpmb_ioctl_ver_cmd(rdev, ptr);
+	case RPMB_IOC_CAP_CMD:
+		return rpmb_ioctl_cap_cmd(rdev, ptr);
+	case RPMB_IOC_PKEY_CMD:
+		return rpmb_ioctl_pkey_cmd(rdev, ptr);
+	case RPMB_IOC_COUNTER_CMD:
+		return rpmb_ioctl_counter_cmd(rdev, ptr);
+	case RPMB_IOC_WBLOCKS_CMD:
+		return rpmb_ioctl_wblocks_cmd(rdev, ptr);
+	case RPMB_IOC_RBLOCKS_CMD:
+		return rpmb_ioctl_rblocks_cmd(rdev, ptr);
+	default:
+		dev_err(&rdev->dev, "unsupported ioctl 0x%x.\n", cmd);
+		return -ENOIOCTLCMD;
+	}
+}
+
+static const struct file_operations rpmb_fops = {
+	.open           = rpmb_open,
+	.release        = rpmb_release,
+	.unlocked_ioctl = rpmb_ioctl,
+	.owner          = THIS_MODULE,
+	.llseek         = noop_llseek,
+};
+
+void rpmb_cdev_prepare(struct rpmb_dev *rdev)
+{
+	rdev->dev.devt = MKDEV(MAJOR(rpmb_devt), rdev->id);
+	rdev->cdev.owner = THIS_MODULE;
+	cdev_init(&rdev->cdev, &rpmb_fops);
+}
+
+void rpmb_cdev_add(struct rpmb_dev *rdev)
+{
+	cdev_add(&rdev->cdev, rdev->dev.devt, 1);
+}
+
+void rpmb_cdev_del(struct rpmb_dev *rdev)
+{
+	if (rdev->dev.devt)
+		cdev_del(&rdev->cdev);
+}
+
+int __init rpmb_cdev_init(void)
+{
+	int ret;
+
+	ret = alloc_chrdev_region(&rpmb_devt, 0, RPMB_MAX_DEVS, "rpmb");
+	if (ret < 0)
+		pr_err("unable to allocate char dev region\n");
+
+	return ret;
+}
+
+void __exit rpmb_cdev_exit(void)
+{
+	unregister_chrdev_region(rpmb_devt, RPMB_MAX_DEVS);
+}
diff --git a/drivers/char/rpmb/core.c b/drivers/char/rpmb/core.c
index a2e21c14986a..e26d605e48e1 100644
--- a/drivers/char/rpmb/core.c
+++ b/drivers/char/rpmb/core.c
@@ -12,6 +12,7 @@
 #include <linux/slab.h>
 
 #include <linux/rpmb.h>
+#include "rpmb-cdev.h"
 
 static DEFINE_IDA(rpmb_ida);
 
@@ -277,6 +278,7 @@ int rpmb_dev_unregister(struct rpmb_dev *rdev)
 		return -EINVAL;
 
 	mutex_lock(&rdev->lock);
+	rpmb_cdev_del(rdev);
 	device_del(&rdev->dev);
 	mutex_unlock(&rdev->lock);
 
@@ -371,9 +373,6 @@ struct rpmb_dev *rpmb_dev_register(struct device *dev, u8 target,
 	if (!ops->read_blocks)
 		return ERR_PTR(-EINVAL);
 
-	if (ops->type == RPMB_TYPE_ANY || ops->type > RPMB_TYPE_MAX)
-		return ERR_PTR(-EINVAL);
-
 	rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
 	if (!rdev)
 		return ERR_PTR(-ENOMEM);
@@ -396,6 +395,8 @@ struct rpmb_dev *rpmb_dev_register(struct device *dev, u8 target,
 	if (ret)
 		goto exit;
 
+	rpmb_cdev_add(rdev);
+
 	dev_dbg(&rdev->dev, "registered device\n");
 
 	return rdev;
@@ -412,11 +413,12 @@ static int __init rpmb_init(void)
 {
 	ida_init(&rpmb_ida);
 	class_register(&rpmb_class);
-	return 0;
+	return rpmb_cdev_init();
 }
 
 static void __exit rpmb_exit(void)
 {
+	rpmb_cdev_exit();
 	class_unregister(&rpmb_class);
 	ida_destroy(&rpmb_ida);
 }
diff --git a/drivers/char/rpmb/rpmb-cdev.h b/drivers/char/rpmb/rpmb-cdev.h
new file mode 100644
index 000000000000..e59ff0c05e9d
--- /dev/null
+++ b/drivers/char/rpmb/rpmb-cdev.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 */
+/*
+ * Copyright (C) 2015-2018 Intel Corp. All rights reserved
+ */
+#ifdef CONFIG_RPMB_INTF_DEV
+int __init rpmb_cdev_init(void);
+void __exit rpmb_cdev_exit(void);
+void rpmb_cdev_prepare(struct rpmb_dev *rdev);
+void rpmb_cdev_add(struct rpmb_dev *rdev);
+void rpmb_cdev_del(struct rpmb_dev *rdev);
+#else
+static inline int __init rpmb_cdev_init(void) { return 0; }
+static inline void __exit rpmb_cdev_exit(void) {}
+static inline void rpmb_cdev_prepare(struct rpmb_dev *rdev) {}
+static inline void rpmb_cdev_add(struct rpmb_dev *rdev) {}
+static inline void rpmb_cdev_del(struct rpmb_dev *rdev) {}
+#endif /* CONFIG_RPMB_INTF_DEV */
diff --git a/include/linux/rpmb.h b/include/linux/rpmb.h
index 718ba7c91ecd..fe44f60efe31 100644
--- a/include/linux/rpmb.h
+++ b/include/linux/rpmb.h
@@ -8,9 +8,13 @@
 
 #include <linux/types.h>
 #include <linux/device.h>
+#include <linux/cdev.h>
+#include <uapi/linux/rpmb.h>
 #include <linux/kref.h>
 #include <linux/key.h>
 
+#define RPMB_API_VERSION 0x80000001
+
 /**
  * struct rpmb_ops - RPMB ops to be implemented by underlying block device
  *
@@ -51,6 +55,8 @@ struct rpmb_ops {
  * @dev        : device
  * @id         : device id
  * @target     : RPMB target/region within the physical device
+ * @cdev       : character dev
+ * @status     : device status
  * @ops        : operation exported by block layer
  */
 struct rpmb_dev {
@@ -58,6 +64,10 @@ struct rpmb_dev {
 	struct device dev;
 	int id;
 	u8 target;
+#ifdef CONFIG_RPMB_INTF_DEV
+	struct cdev cdev;
+	unsigned long status;
+#endif /* CONFIG_RPMB_INTF_DEV */
 	const struct rpmb_ops *ops;
 };
 
diff --git a/include/uapi/linux/rpmb.h b/include/uapi/linux/rpmb.h
new file mode 100644
index 000000000000..3957b785cdd5
--- /dev/null
+++ b/include/uapi/linux/rpmb.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
+/*
+ * Copyright (C) 2015-2018 Intel Corp. All rights reserved
+ * Copyright (C) 2021 Linaro Ltd
+ */
+#ifndef _UAPI_LINUX_RPMB_H_
+#define _UAPI_LINUX_RPMB_H_
+
+#include <linux/types.h>
+
+/**
+ * struct rpmb_ioc_ver_cmd - rpmb api version
+ *
+ * @api_version: rpmb API version.
+ */
+struct rpmb_ioc_ver_cmd {
+	__u32 api_version;
+} __packed;
+
+enum rpmb_auth_method {
+	RPMB_HMAC_ALGO_SHA_256 = 0,
+};
+
+/**
+ * struct rpmb_ioc_cap_cmd - rpmb capabilities
+ *
+ * @target: rpmb target/region within RPMB partition.
+ * @capacity: storage capacity (in units of 128K)
+ * @block_size: storage data block size (in units of 256B)
+ * @wr_cnt_max: maximal number of block that can be written in a single request.
+ * @rd_cnt_max: maximal number of block that can be read in a single request.
+ * @auth_method: authentication method: currently always HMAC_SHA_256
+ * @reserved: reserved to align to 4 bytes.
+ */
+struct rpmb_ioc_cap_cmd {
+	__u16 target;
+	__u16 capacity;
+	__u16 block_size;
+	__u16 wr_cnt_max;
+	__u16 rd_cnt_max;
+	__u16 auth_method;
+	__u16 reserved;
+} __attribute__((packed));
+
+/**
+ * struct rpmb_ioc_blocks_cmd - read/write blocks to/from RPMB
+ *
+ * @keyid: key_serial_t of key to use
+ * @addr: index into device (units of 256B blocks)
+ * @count: number of 256B blocks
+ * @data: pointer to data to write/read
+ */
+struct rpmb_ioc_blocks_cmd {
+	__s32 key; /* key_serial_t */
+	__u32 addr;
+	__u32 count;
+	__u8 __user *data;
+} __attribute__((packed));
+
+
+#define RPMB_IOC_VER_CMD     _IOR(0xB8, 80, struct rpmb_ioc_ver_cmd)
+#define RPMB_IOC_CAP_CMD     _IOR(0xB8, 81, struct rpmb_ioc_cap_cmd)
+#define RPMB_IOC_PKEY_CMD    _IOW(0xB8, 82, key_serial_t)
+#define RPMB_IOC_COUNTER_CMD _IOR(0xB8, 84, int)
+#define RPMB_IOC_WBLOCKS_CMD _IOW(0xB8, 85, struct rpmb_ioc_blocks_cmd)
+#define RPMB_IOC_RBLOCKS_CMD _IOR(0xB8, 86, struct rpmb_ioc_blocks_cmd)
+
+#endif /* _UAPI_LINUX_RPMB_H_ */
