Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index dac895d..59f2528 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 #
 # Hardware Random Number Generator (RNG) configuration
 #
@@ -424,6 +425,21 @@
 	  will be called exynos-trng.
 
 	  If unsure, say Y.
+
+config HW_RANDOM_OPTEE
+	tristate "OP-TEE based Random Number Generator support"
+	depends on OPTEE
+	default HW_RANDOM
+	help
+	  This  driver provides support for OP-TEE based Random Number
+	  Generator on ARM SoCs where hardware entropy sources are not
+	  accessible to normal world (Linux).
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called optee-rng.
+
+	  If unsure, say Y.
+
 endif # HW_RANDOM
 
 config UML_RANDOM
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index e35ec3c..7c9ef4a 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -38,3 +38,4 @@
 obj-$(CONFIG_HW_RANDOM_MTK)	+= mtk-rng.o
 obj-$(CONFIG_HW_RANDOM_S390) += s390-trng.o
 obj-$(CONFIG_HW_RANDOM_KEYSTONE) += ks-sa-rng.o
+obj-$(CONFIG_HW_RANDOM_OPTEE) += optee-rng.o
diff --git a/drivers/char/hw_random/atmel-rng.c b/drivers/char/hw_random/atmel-rng.c
index 4334262..e557057 100644
--- a/drivers/char/hw_random/atmel-rng.c
+++ b/drivers/char/hw_random/atmel-rng.c
@@ -86,7 +86,7 @@
 	trng->rng.name = pdev->name;
 	trng->rng.read = atmel_trng_read;
 
-	ret = hwrng_register(&trng->rng);
+	ret = devm_hwrng_register(&pdev->dev, &trng->rng);
 	if (ret)
 		goto err_register;
 
@@ -103,7 +103,6 @@
 {
 	struct atmel_trng *trng = platform_get_drvdata(pdev);
 
-	hwrng_unregister(&trng->rng);
 
 	atmel_trng_disable(trng);
 	clk_disable_unprepare(trng->clk);
diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
index 6767d96..f759790 100644
--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c
@@ -1,10 +1,7 @@
-/**
+// SPDX-License-Identifier: GPL-2.0
+/*
  * Copyright (c) 2010-2012 Broadcom. All rights reserved.
  * Copyright (c) 2013 Lubomir Rintel
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License ("GPL")
- * version 2, as published by the Free Software Foundation.
  */
 
 #include <linux/hw_random.h>
@@ -171,14 +168,16 @@
 	priv->rng.read = bcm2835_rng_read;
 	priv->rng.cleanup = bcm2835_rng_cleanup;
 
-	rng_id = of_match_node(bcm2835_rng_of_match, np);
-	if (!rng_id)
-		return -EINVAL;
+	if (dev_of_node(dev)) {
+		rng_id = of_match_node(bcm2835_rng_of_match, np);
+		if (!rng_id)
+			return -EINVAL;
 
-	/* Check for rng init function, execute it */
-	of_data = rng_id->data;
-	if (of_data)
-		priv->mask_interrupts = of_data->mask_interrupts;
+		/* Check for rng init function, execute it */
+		of_data = rng_id->data;
+		if (of_data)
+			priv->mask_interrupts = of_data->mask_interrupts;
+	}
 
 	/* register driver */
 	err = devm_hwrng_register(dev, &priv->rng);
diff --git a/drivers/char/hw_random/cavium-rng-vf.c b/drivers/char/hw_random/cavium-rng-vf.c
index 2d1352b..3de4a6a 100644
--- a/drivers/char/hw_random/cavium-rng-vf.c
+++ b/drivers/char/hw_random/cavium-rng-vf.c
@@ -67,7 +67,7 @@
 
 	pci_set_drvdata(pdev, rng);
 
-	ret = hwrng_register(&rng->ops);
+	ret = devm_hwrng_register(&pdev->dev, &rng->ops);
 	if (ret) {
 		dev_err(&pdev->dev, "Error registering device as HWRNG.\n");
 		return ret;
@@ -76,14 +76,6 @@
 	return 0;
 }
 
-/* Remove the VF */
-static void  cavium_rng_remove_vf(struct pci_dev *pdev)
-{
-	struct cavium_rng *rng;
-
-	rng = pci_get_drvdata(pdev);
-	hwrng_unregister(&rng->ops);
-}
 
 static const struct pci_device_id cavium_rng_vf_id_table[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa033), 0, 0, 0},
@@ -95,7 +87,6 @@
 	.name		= "cavium_rng_vf",
 	.id_table	= cavium_rng_vf_id_table,
 	.probe		= cavium_rng_probe_vf,
-	.remove		= cavium_rng_remove_vf,
 };
 module_pci_driver(cavium_rng_vf_driver);
 
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index aaf9e5a..8d53b8e 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -4,7 +4,7 @@
  * Copyright 2006 Michael Buesch <m@bues.ch>
  * Copyright 2005 (c) MontaVista Software, Inc.
  *
- * Please read Documentation/hw_random.txt for details on use.
+ * Please read Documentation/admin-guide/hw_random.rst for details on use.
  *
  * This software may be used and distributed according to the terms
  * of the GNU General Public License, incorporated herein by reference.
@@ -44,10 +44,10 @@
 
 module_param(current_quality, ushort, 0644);
 MODULE_PARM_DESC(current_quality,
-		 "current hwrng entropy estimation per mill");
+		 "current hwrng entropy estimation per 1024 bits of input");
 module_param(default_quality, ushort, 0644);
 MODULE_PARM_DESC(default_quality,
-		 "default entropy content of hwrng per mill");
+		 "default entropy content of hwrng per 1024 bits of input");
 
 static void drop_current_rng(void);
 static int hwrng_init(struct hwrng *rng);
@@ -67,7 +67,7 @@
 	size_t size = min_t(size_t, 16, rng_buffer_size());
 
 	mutex_lock(&reading_mutex);
-	bytes_read = rng_get_data(rng, rng_buffer, size, 1);
+	bytes_read = rng_get_data(rng, rng_buffer, size, 0);
 	mutex_unlock(&reading_mutex);
 	if (bytes_read > 0)
 		add_device_randomness(rng_buffer, bytes_read);
diff --git a/drivers/char/hw_random/exynos-trng.c b/drivers/char/hw_random/exynos-trng.c
index 9423576..b4b52ab 100644
--- a/drivers/char/hw_random/exynos-trng.c
+++ b/drivers/char/hw_random/exynos-trng.c
@@ -153,7 +153,7 @@
 		goto err_clock;
 	}
 
-	ret = hwrng_register(&trng->rng);
+	ret = devm_hwrng_register(&pdev->dev, &trng->rng);
 	if (ret) {
 		dev_err(&pdev->dev, "Could not register hwrng device.\n");
 		goto err_register;
@@ -179,7 +179,6 @@
 {
 	struct exynos_trng_dev *trng =  platform_get_drvdata(pdev);
 
-	hwrng_unregister(&trng->rng);
 	clk_disable_unprepare(trng->clk);
 
 	pm_runtime_put_sync(&pdev->dev);
diff --git a/drivers/char/hw_random/hisi-rng.c b/drivers/char/hw_random/hisi-rng.c
index 40d9657..c663d5d 100644
--- a/drivers/char/hw_random/hisi-rng.c
+++ b/drivers/char/hw_random/hisi-rng.c
@@ -1,9 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2016 HiSilicon Co., Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #include <linux/err.h>
diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index 14730be..30cf00f 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -1,15 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * RNG driver for Freescale RNGC
  *
  * Copyright (C) 2008-2012 Freescale Semiconductor, Inc.
  * Copyright (C) 2017 Martin Kaiser <martin@kaiser.cx>
- *
- * The code contained herein is licensed under the GNU General Public
- * License. You may obtain a copy of the GNU General Public License
- * Version 2 or later at the following locations:
- *
- * http://www.opensource.org/licenses/gpl-license.html
- * http://www.gnu.org/copyleft/gpl.html
  */
 
 #include <linux/module.h>
@@ -202,7 +196,6 @@
 static int imx_rngc_probe(struct platform_device *pdev)
 {
 	struct imx_rngc *rngc;
-	struct resource *res;
 	int ret;
 	int irq;
 
@@ -210,8 +203,7 @@
 	if (!rngc)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	rngc->base = devm_ioremap_resource(&pdev->dev, res);
+	rngc->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(rngc->base))
 		return PTR_ERR(rngc->base);
 
diff --git a/drivers/char/hw_random/iproc-rng200.c b/drivers/char/hw_random/iproc-rng200.c
index 8b5a20b..92be1c0 100644
--- a/drivers/char/hw_random/iproc-rng200.c
+++ b/drivers/char/hw_random/iproc-rng200.c
@@ -220,6 +220,7 @@
 }
 
 static const struct of_device_id iproc_rng200_of_match[] = {
+	{ .compatible = "brcm,bcm7211-rng200", },
 	{ .compatible = "brcm,bcm7278-rng200", },
 	{ .compatible = "brcm,iproc-rng200", },
 	{},
diff --git a/drivers/char/hw_random/ks-sa-rng.c b/drivers/char/hw_random/ks-sa-rng.c
index 62c6696..a674300 100644
--- a/drivers/char/hw_random/ks-sa-rng.c
+++ b/drivers/char/hw_random/ks-sa-rng.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Random Number Generator driver for the Keystone SOC
  *
@@ -5,15 +6,6 @@
  *
  * Authors:	Sandeep Nair
  *		Vitaly Andrianov
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
  */
 
 #include <linux/hw_random.h>
diff --git a/drivers/char/hw_random/meson-rng.c b/drivers/char/hw_random/meson-rng.c
index 2e23be8..76e693d 100644
--- a/drivers/char/hw_random/meson-rng.c
+++ b/drivers/char/hw_random/meson-rng.c
@@ -1,58 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
 /*
- * This file is provided under a dual BSD/GPLv2 license.  When using or
- * redistributing this file, you may do so under either license.
- *
- * GPL LICENSE SUMMARY
- *
  * Copyright (c) 2016 BayLibre, SAS.
  * Author: Neil Armstrong <narmstrong@baylibre.com>
  * Copyright (C) 2014 Amlogic, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see <http://www.gnu.org/licenses/>.
- * The full GNU General Public License is included in this distribution
- * in the file called COPYING.
- *
- * BSD LICENSE
- *
- * Copyright (c) 2016 BayLibre, SAS.
- * Author: Neil Armstrong <narmstrong@baylibre.com>
- * Copyright (C) 2014 Amlogic, Inc.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- *   * Redistributions of source code must retain the above copyright
- *     notice, this list of conditions and the following disclaimer.
- *   * Redistributions in binary form must reproduce the above copyright
- *     notice, this list of conditions and the following disclaimer in
- *     the documentation and/or other materials provided with the
- *     distribution.
- *   * Neither the name of Intel Corporation nor the names of its
- *     contributors may be used to endorse or promote products derived
- *     from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include <linux/err.h>
 #include <linux/module.h>
diff --git a/drivers/char/hw_random/mtk-rng.c b/drivers/char/hw_random/mtk-rng.c
index 7f99cd5..e649be5 100644
--- a/drivers/char/hw_random/mtk-rng.c
+++ b/drivers/char/hw_random/mtk-rng.c
@@ -1,17 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Driver for Mediatek Hardware Random Number Generator
  *
  * Copyright (C) 2017 Sean Wang <sean.wang@mediatek.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
  */
 #define MTK_RNG_DEV KBUILD_MODNAME
 
diff --git a/drivers/char/hw_random/mxc-rnga.c b/drivers/char/hw_random/mxc-rnga.c
index f83bee5..025083c 100644
--- a/drivers/char/hw_random/mxc-rnga.c
+++ b/drivers/char/hw_random/mxc-rnga.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * RNG driver for Freescale RNGA
  *
@@ -6,12 +7,6 @@
  */
 
 /*
- * The code contained herein is licensed under the GNU General Public
- * License. You may obtain a copy of the GNU General Public License
- * Version 2 or later at the following locations:
- *
- * http://www.opensource.org/licenses/gpl-license.html
- * http://www.gnu.org/copyleft/gpl.html
  *
  * This driver is based on other RNG drivers.
  */
@@ -139,7 +134,6 @@
 static int __init mxc_rnga_probe(struct platform_device *pdev)
 {
 	int err;
-	struct resource *res;
 	struct mxc_rng *mxc_rng;
 
 	mxc_rng = devm_kzalloc(&pdev->dev, sizeof(*mxc_rng), GFP_KERNEL);
@@ -163,8 +157,7 @@
 	if (err)
 		return err;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	mxc_rng->mem = devm_ioremap_resource(&pdev->dev, res);
+	mxc_rng->mem = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(mxc_rng->mem)) {
 		err = PTR_ERR(mxc_rng->mem);
 		goto err_ioremap;
diff --git a/drivers/char/hw_random/n2-drv.c b/drivers/char/hw_random/n2-drv.c
index f841151..73e4081 100644
--- a/drivers/char/hw_random/n2-drv.c
+++ b/drivers/char/hw_random/n2-drv.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /* n2-drv.c: Niagara-2 RNG driver.
  *
  * Copyright (C) 2008, 2011 David S. Miller <davem@davemloft.net>
@@ -767,7 +768,7 @@
 	np->hwrng.data_read = n2rng_data_read;
 	np->hwrng.priv = (unsigned long) np;
 
-	err = hwrng_register(&np->hwrng);
+	err = devm_hwrng_register(&op->dev, &np->hwrng);
 	if (err)
 		goto out_hvapi_unregister;
 
@@ -792,8 +793,6 @@
 
 	cancel_delayed_work_sync(&np->work);
 
-	hwrng_unregister(&np->hwrng);
-
 	sun4v_hvapi_unregister(HV_GRP_RNG);
 
 	return 0;
diff --git a/drivers/char/hw_random/nomadik-rng.c b/drivers/char/hw_random/nomadik-rng.c
index 9c85815..74ed29f 100644
--- a/drivers/char/hw_random/nomadik-rng.c
+++ b/drivers/char/hw_random/nomadik-rng.c
@@ -1,11 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Nomadik RNG support
  *  Copyright 2009 Alessandro Rubini
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
  */
 
 #include <linux/kernel.h>
@@ -61,7 +57,7 @@
 	if (!base)
 		goto out_release;
 	nmk_rng.priv = (unsigned long)base;
-	ret = hwrng_register(&nmk_rng);
+	ret = devm_hwrng_register(&dev->dev, &nmk_rng);
 	if (ret)
 		goto out_release;
 	return 0;
@@ -75,7 +71,6 @@
 
 static int nmk_rng_remove(struct amba_device *dev)
 {
-	hwrng_unregister(&nmk_rng);
 	amba_release_regions(dev);
 	clk_disable(rng_clk);
 	return 0;
diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index b65ff69..b27f396 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -443,6 +443,7 @@
 	priv->rng.read = omap_rng_do_read;
 	priv->rng.init = omap_rng_init;
 	priv->rng.cleanup = omap_rng_cleanup;
+	priv->rng.quality = 900;
 
 	priv->rng.priv = (unsigned long)priv;
 	platform_set_drvdata(pdev, priv);
@@ -499,7 +500,7 @@
 	if (ret)
 		goto err_register;
 
-	ret = hwrng_register(&priv->rng);
+	ret = devm_hwrng_register(&pdev->dev, &priv->rng);
 	if (ret)
 		goto err_register;
 
@@ -524,7 +525,6 @@
 {
 	struct omap_rng_dev *priv = platform_get_drvdata(pdev);
 
-	hwrng_unregister(&priv->rng);
 
 	priv->pdata->cleanup(priv);
 
diff --git a/drivers/char/hw_random/optee-rng.c b/drivers/char/hw_random/optee-rng.c
new file mode 100644
index 0000000..ddfbaba
--- /dev/null
+++ b/drivers/char/hw_random/optee-rng.c
@@ -0,0 +1,306 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018-2019 Linaro Ltd.
+ */
+
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/hw_random.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include <linux/uuid.h>
+
+#define DRIVER_NAME "optee-rng"
+
+#define TEE_ERROR_HEALTH_TEST_FAIL	0x00000001
+
+/*
+ * TA_CMD_GET_ENTROPY - Get Entropy from RNG
+ *
+ * param[0] (inout memref) - Entropy buffer memory reference
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ * TEE_ERROR_NOT_SUPPORTED - Requested entropy size greater than size of pool
+ * TEE_ERROR_HEALTH_TEST_FAIL - Continuous health testing failed
+ */
+#define TA_CMD_GET_ENTROPY		0x0
+
+/*
+ * TA_CMD_GET_RNG_INFO - Get RNG information
+ *
+ * param[0] (out value) - value.a: RNG data-rate in bytes per second
+ *                        value.b: Quality/Entropy per 1024 bit of data
+ * param[1] unused
+ * param[2] unused
+ * param[3] unused
+ *
+ * Result:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ */
+#define TA_CMD_GET_RNG_INFO		0x1
+
+#define MAX_ENTROPY_REQ_SZ		(4 * 1024)
+
+/**
+ * struct optee_rng_private - OP-TEE Random Number Generator private data
+ * @dev:		OP-TEE based RNG device.
+ * @ctx:		OP-TEE context handler.
+ * @session_id:		RNG TA session identifier.
+ * @data_rate:		RNG data rate.
+ * @entropy_shm_pool:	Memory pool shared with RNG device.
+ * @optee_rng:		OP-TEE RNG driver structure.
+ */
+struct optee_rng_private {
+	struct device *dev;
+	struct tee_context *ctx;
+	u32 session_id;
+	u32 data_rate;
+	struct tee_shm *entropy_shm_pool;
+	struct hwrng optee_rng;
+};
+
+#define to_optee_rng_private(r) \
+		container_of(r, struct optee_rng_private, optee_rng)
+
+static size_t get_optee_rng_data(struct optee_rng_private *pvt_data,
+				 void *buf, size_t req_size)
+{
+	int ret = 0;
+	u8 *rng_data = NULL;
+	size_t rng_size = 0;
+	struct tee_ioctl_invoke_arg inv_arg;
+	struct tee_param param[4];
+
+	memset(&inv_arg, 0, sizeof(inv_arg));
+	memset(&param, 0, sizeof(param));
+
+	/* Invoke TA_CMD_GET_ENTROPY function of Trusted App */
+	inv_arg.func = TA_CMD_GET_ENTROPY;
+	inv_arg.session = pvt_data->session_id;
+	inv_arg.num_params = 4;
+
+	/* Fill invoke cmd params */
+	param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT;
+	param[0].u.memref.shm = pvt_data->entropy_shm_pool;
+	param[0].u.memref.size = req_size;
+	param[0].u.memref.shm_offs = 0;
+
+	ret = tee_client_invoke_func(pvt_data->ctx, &inv_arg, param);
+	if ((ret < 0) || (inv_arg.ret != 0)) {
+		dev_err(pvt_data->dev, "TA_CMD_GET_ENTROPY invoke err: %x\n",
+			inv_arg.ret);
+		return 0;
+	}
+
+	rng_data = tee_shm_get_va(pvt_data->entropy_shm_pool, 0);
+	if (IS_ERR(rng_data)) {
+		dev_err(pvt_data->dev, "tee_shm_get_va failed\n");
+		return 0;
+	}
+
+	rng_size = param[0].u.memref.size;
+	memcpy(buf, rng_data, rng_size);
+
+	return rng_size;
+}
+
+static int optee_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
+{
+	struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
+	size_t read = 0, rng_size = 0;
+	int timeout = 1;
+	u8 *data = buf;
+
+	if (max > MAX_ENTROPY_REQ_SZ)
+		max = MAX_ENTROPY_REQ_SZ;
+
+	while (read == 0) {
+		rng_size = get_optee_rng_data(pvt_data, data, (max - read));
+
+		data += rng_size;
+		read += rng_size;
+
+		if (wait) {
+			if (timeout-- == 0)
+				return read;
+			msleep((1000 * (max - read)) / pvt_data->data_rate);
+		} else {
+			return read;
+		}
+	}
+
+	return read;
+}
+
+static int optee_rng_init(struct hwrng *rng)
+{
+	struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
+	struct tee_shm *entropy_shm_pool = NULL;
+
+	entropy_shm_pool = tee_shm_alloc(pvt_data->ctx, MAX_ENTROPY_REQ_SZ,
+					 TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
+	if (IS_ERR(entropy_shm_pool)) {
+		dev_err(pvt_data->dev, "tee_shm_alloc failed\n");
+		return PTR_ERR(entropy_shm_pool);
+	}
+
+	pvt_data->entropy_shm_pool = entropy_shm_pool;
+
+	return 0;
+}
+
+static void optee_rng_cleanup(struct hwrng *rng)
+{
+	struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
+
+	tee_shm_free(pvt_data->entropy_shm_pool);
+}
+
+static struct optee_rng_private pvt_data = {
+	.optee_rng = {
+		.name		= DRIVER_NAME,
+		.init		= optee_rng_init,
+		.cleanup	= optee_rng_cleanup,
+		.read		= optee_rng_read,
+	}
+};
+
+static int get_optee_rng_info(struct device *dev)
+{
+	int ret = 0;
+	struct tee_ioctl_invoke_arg inv_arg;
+	struct tee_param param[4];
+
+	memset(&inv_arg, 0, sizeof(inv_arg));
+	memset(&param, 0, sizeof(param));
+
+	/* Invoke TA_CMD_GET_RNG_INFO function of Trusted App */
+	inv_arg.func = TA_CMD_GET_RNG_INFO;
+	inv_arg.session = pvt_data.session_id;
+	inv_arg.num_params = 4;
+
+	/* Fill invoke cmd params */
+	param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+
+	ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
+	if ((ret < 0) || (inv_arg.ret != 0)) {
+		dev_err(dev, "TA_CMD_GET_RNG_INFO invoke err: %x\n",
+			inv_arg.ret);
+		return -EINVAL;
+	}
+
+	pvt_data.data_rate = param[0].u.value.a;
+	pvt_data.optee_rng.quality = param[0].u.value.b;
+
+	return 0;
+}
+
+static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
+{
+	if (ver->impl_id == TEE_IMPL_ID_OPTEE)
+		return 1;
+	else
+		return 0;
+}
+
+static int optee_rng_probe(struct device *dev)
+{
+	struct tee_client_device *rng_device = to_tee_client_device(dev);
+	int ret = 0, err = -ENODEV;
+	struct tee_ioctl_open_session_arg sess_arg;
+
+	memset(&sess_arg, 0, sizeof(sess_arg));
+
+	/* Open context with TEE driver */
+	pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL,
+					       NULL);
+	if (IS_ERR(pvt_data.ctx))
+		return -ENODEV;
+
+	/* Open session with hwrng Trusted App */
+	memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
+	sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
+	sess_arg.num_params = 0;
+
+	ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL);
+	if ((ret < 0) || (sess_arg.ret != 0)) {
+		dev_err(dev, "tee_client_open_session failed, err: %x\n",
+			sess_arg.ret);
+		err = -EINVAL;
+		goto out_ctx;
+	}
+	pvt_data.session_id = sess_arg.session;
+
+	err = get_optee_rng_info(dev);
+	if (err)
+		goto out_sess;
+
+	err = hwrng_register(&pvt_data.optee_rng);
+	if (err) {
+		dev_err(dev, "hwrng registration failed (%d)\n", err);
+		goto out_sess;
+	}
+
+	pvt_data.dev = dev;
+
+	return 0;
+
+out_sess:
+	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
+out_ctx:
+	tee_client_close_context(pvt_data.ctx);
+
+	return err;
+}
+
+static int optee_rng_remove(struct device *dev)
+{
+	hwrng_unregister(&pvt_data.optee_rng);
+	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
+	tee_client_close_context(pvt_data.ctx);
+
+	return 0;
+}
+
+static const struct tee_client_device_id optee_rng_id_table[] = {
+	{UUID_INIT(0xab7a617c, 0xb8e7, 0x4d8f,
+		   0x83, 0x01, 0xd0, 0x9b, 0x61, 0x03, 0x6b, 0x64)},
+	{}
+};
+
+MODULE_DEVICE_TABLE(tee, optee_rng_id_table);
+
+static struct tee_client_driver optee_rng_driver = {
+	.id_table	= optee_rng_id_table,
+	.driver		= {
+		.name		= DRIVER_NAME,
+		.bus		= &tee_bus_type,
+		.probe		= optee_rng_probe,
+		.remove		= optee_rng_remove,
+	},
+};
+
+static int __init optee_rng_mod_init(void)
+{
+	return driver_register(&optee_rng_driver.driver);
+}
+
+static void __exit optee_rng_mod_exit(void)
+{
+	driver_unregister(&optee_rng_driver.driver);
+}
+
+module_init(optee_rng_mod_init);
+module_exit(optee_rng_mod_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Sumit Garg <sumit.garg@linaro.org>");
+MODULE_DESCRIPTION("OP-TEE based random number generator driver");
diff --git a/drivers/char/hw_random/pasemi-rng.c b/drivers/char/hw_random/pasemi-rng.c
index 545df48..24b1460 100644
--- a/drivers/char/hw_random/pasemi-rng.c
+++ b/drivers/char/hw_random/pasemi-rng.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2006-2007 PA Semi, Inc
  *
  * Maintained by: Olof Johansson <olof@lixom.net>
  *
  * Driver for the PWRficient onchip rng
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  */
 
 #include <linux/module.h>
diff --git a/drivers/char/hw_random/pic32-rng.c b/drivers/char/hw_random/pic32-rng.c
index 9b5e68a..90f498c 100644
--- a/drivers/char/hw_random/pic32-rng.c
+++ b/drivers/char/hw_random/pic32-rng.c
@@ -1,17 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * PIC32 RNG driver
  *
  * Joshua Henderson <joshua.henderson@microchip.com>
  * Copyright (C) 2016 Microchip Technology Inc.  All rights reserved.
- *
- * This program is free software; you can distribute it and/or modify it
- * under the terms of the GNU General Public License (Version 2) as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * for more details.
  */
 
 #include <linux/clk.h>
diff --git a/drivers/char/hw_random/powernv-rng.c b/drivers/char/hw_random/powernv-rng.c
index 791182a..8da1d79 100644
--- a/drivers/char/hw_random/powernv-rng.c
+++ b/drivers/char/hw_random/powernv-rng.c
@@ -1,10 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright 2013 Michael Ellerman, Guo Chao, IBM Corp.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
  */
 
 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
@@ -37,18 +33,11 @@
 	.read = powernv_rng_read,
 };
 
-static int powernv_rng_remove(struct platform_device *pdev)
-{
-	hwrng_unregister(&powernv_hwrng);
-
-	return 0;
-}
-
 static int powernv_rng_probe(struct platform_device *pdev)
 {
 	int rc;
 
-	rc = hwrng_register(&powernv_hwrng);
+	rc = devm_hwrng_register(&pdev->dev, &powernv_hwrng);
 	if (rc) {
 		/* We only register one device, ignore any others */
 		if (rc == -EEXIST)
@@ -74,7 +63,6 @@
 		.of_match_table = powernv_rng_match,
 	},
 	.probe	= powernv_rng_probe,
-	.remove = powernv_rng_remove,
 };
 module_platform_driver(powernv_rng_driver);
 
diff --git a/drivers/char/hw_random/pseries-rng.c b/drivers/char/hw_random/pseries-rng.c
index 4e2a3f6..8038a8a 100644
--- a/drivers/char/hw_random/pseries-rng.c
+++ b/drivers/char/hw_random/pseries-rng.c
@@ -1,20 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2010 Michael Neuling IBM Corporation
  *
  * Driver for the pseries hardware RNG for POWER7+ and above
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
diff --git a/drivers/char/hw_random/s390-trng.c b/drivers/char/hw_random/s390-trng.c
index aca48e8..413cacb 100644
--- a/drivers/char/hw_random/s390-trng.c
+++ b/drivers/char/hw_random/s390-trng.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * s390 TRNG device driver
  *
@@ -6,11 +7,6 @@
 
  * Copyright IBM Corp. 2017
  * Author(s): Harald Freudenberger <freude@de.ibm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License (version 2 only)
- * as published by the Free Software Foundation.
- *
  */
 
 #define KMSG_COMPONENT "trng"
diff --git a/drivers/char/hw_random/st-rng.c b/drivers/char/hw_random/st-rng.c
index 938ec10..8634483 100644
--- a/drivers/char/hw_random/st-rng.c
+++ b/drivers/char/hw_random/st-rng.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * ST Random Number Generator Driver ST's Platforms
  *
@@ -5,10 +6,6 @@
  *         Lee Jones <lee.jones@linaro.org>
  *
  * Copyright (C) 2015 STMicroelectronics (R&D) Limited
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #include <linux/clk.h>
@@ -105,7 +102,7 @@
 
 	dev_set_drvdata(&pdev->dev, ddata);
 
-	ret = hwrng_register(&ddata->ops);
+	ret = devm_hwrng_register(&pdev->dev, &ddata->ops);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to register HW RNG\n");
 		clk_disable_unprepare(clk);
@@ -121,8 +118,6 @@
 {
 	struct st_rng_data *ddata = dev_get_drvdata(&pdev->dev);
 
-	hwrng_unregister(&ddata->ops);
-
 	clk_disable_unprepare(ddata->clk);
 
 	return 0;
diff --git a/drivers/char/hw_random/stm32-rng.c b/drivers/char/hw_random/stm32-rng.c
index 042860d..38324c2 100644
--- a/drivers/char/hw_random/stm32-rng.c
+++ b/drivers/char/hw_random/stm32-rng.c
@@ -1,15 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (c) 2015, Daniel Thompson
- *
- * This file is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This file is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
  */
 
 #include <linux/clk.h>
@@ -161,6 +152,7 @@
 #endif
 	priv->rng.read = stm32_rng_read,
 	priv->rng.priv = (unsigned long) dev;
+	priv->rng.quality = 900;
 
 	pm_runtime_set_autosuspend_delay(dev, 100);
 	pm_runtime_use_autosuspend(dev);
@@ -169,6 +161,13 @@
 	return devm_hwrng_register(dev, &priv->rng);
 }
 
+static int stm32_rng_remove(struct platform_device *ofdev)
+{
+	pm_runtime_disable(&ofdev->dev);
+
+	return 0;
+}
+
 #ifdef CONFIG_PM
 static int stm32_rng_runtime_suspend(struct device *dev)
 {
@@ -210,6 +209,7 @@
 		.of_match_table = stm32_rng_match,
 	},
 	.probe = stm32_rng_probe,
+	.remove = stm32_rng_remove,
 };
 
 module_platform_driver(stm32_rng_driver);
diff --git a/drivers/char/hw_random/timeriomem-rng.c b/drivers/char/hw_random/timeriomem-rng.c
index f615684..e262445 100644
--- a/drivers/char/hw_random/timeriomem-rng.c
+++ b/drivers/char/hw_random/timeriomem-rng.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * drivers/char/hw_random/timeriomem-rng.c
  *
@@ -7,10 +8,6 @@
  *   Copyright 2005 (c) MontaVista Software, Inc.
  *   Author: Deepak Saxena <dsaxena@plexity.net>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
  * Overview:
  *   This driver is useful for platforms that have an IO range that provides
  *   periodic random data from a single IO memory address.  All the platform
@@ -120,9 +117,9 @@
 	if (!res)
 		return -ENXIO;
 
-	if (res->start % 4 != 0 || resource_size(res) != 4) {
+	if (res->start % 4 != 0 || resource_size(res) < 4) {
 		dev_err(&pdev->dev,
-			"address must be four bytes wide and aligned\n");
+			"address must be at least four bytes wide and 32-bit aligned\n");
 		return -EINVAL;
 	}
 
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c
index b89df66..718d8c0 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -1,20 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Randomness driver for virtio
  *  Copyright (C) 2007, 2008 Rusty Russell IBM Corporation
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
- *
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  */
 
 #include <linux/err.h>
@@ -73,7 +60,7 @@
 
 	if (!vi->busy) {
 		vi->busy = true;
-		init_completion(&vi->have_data);
+		reinit_completion(&vi->have_data);
 		register_buffer(vi, buf, size);
 	}
 
diff --git a/drivers/char/hw_random/xgene-rng.c b/drivers/char/hw_random/xgene-rng.c
index 7175579..7e568db 100644
--- a/drivers/char/hw_random/xgene-rng.c
+++ b/drivers/char/hw_random/xgene-rng.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * APM X-Gene SoC RNG Driver
  *
@@ -5,20 +6,6 @@
  * Author: Rameshwar Prasad Sahu <rsahu@apm.com>
  *	   Shamal Winchurkar <swinchurkar@apm.com>
  *	   Feng Kan <fkan@apm.com>
- *
- * This program is free software; you can redistribute  it and/or modify it
- * under  the terms of  the GNU General  Public License as published by the
- * Free Software Foundation;  either version 2 of the  License, or (at your
- * option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *
  */
 
 #include <linux/acpi.h>
@@ -374,7 +361,7 @@
 
 	xgene_rng_func.priv = (unsigned long) ctx;
 
-	rc = hwrng_register(&xgene_rng_func);
+	rc = devm_hwrng_register(&pdev->dev, &xgene_rng_func);
 	if (rc) {
 		dev_err(&pdev->dev, "RNG registering failed error %d\n", rc);
 		if (!IS_ERR(ctx->clk))
@@ -388,7 +375,6 @@
 			rc);
 		if (!IS_ERR(ctx->clk))
 			clk_disable_unprepare(ctx->clk);
-		hwrng_unregister(&xgene_rng_func);
 		return rc;
 	}
 
@@ -405,7 +391,6 @@
 		dev_err(&pdev->dev, "RNG init wakeup failed error %d\n", rc);
 	if (!IS_ERR(ctx->clk))
 		clk_disable_unprepare(ctx->clk);
-	hwrng_unregister(&xgene_rng_func);
 
 	return rc;
 }