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authorLinus Torvalds <torvalds@linux-foundation.org>2015-11-04 09:11:12 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-04 09:11:12 -0800
commitccc9d4a6d640cbde05d519edeb727881646cf71b (patch)
tree736c90b100703501d5e3fa3eccc57a48f70bef14 /drivers/char/hw_random
parent66ef3493d4bb387f5a83915e33dc893102fd1b43 (diff)
parent271817a3e92c0455bda5856d87eca244ad67d3a2 (diff)
downloadlinux-ccc9d4a6d640cbde05d519edeb727881646cf71b.tar.bz2
Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu: "API: - Add support for cipher output IVs in testmgr - Add missing crypto_ahash_blocksize helper - Mark authenc and des ciphers as not allowed under FIPS. Algorithms: - Add CRC support to 842 compression - Add keywrap algorithm - A number of changes to the akcipher interface: + Separate functions for setting public/private keys. + Use SG lists. Drivers: - Add Intel SHA Extension optimised SHA1 and SHA256 - Use dma_map_sg instead of custom functions in crypto drivers - Add support for STM32 RNG - Add support for ST RNG - Add Device Tree support to exynos RNG driver - Add support for mxs-dcp crypto device on MX6SL - Add xts(aes) support to caam - Add ctr(aes) and xts(aes) support to qat - A large set of fixes from Russell King for the marvell/cesa driver" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (115 commits) crypto: asymmetric_keys - Fix unaligned access in x509_get_sig_params() crypto: akcipher - Don't #include crypto/public_key.h as the contents aren't used hwrng: exynos - Add Device Tree support hwrng: exynos - Fix missing configuration after suspend to RAM hwrng: exynos - Add timeout for waiting on init done dt-bindings: rng: Describe Exynos4 PRNG bindings crypto: marvell/cesa - use __le32 for hardware descriptors crypto: marvell/cesa - fix missing cpu_to_le32() in mv_cesa_dma_add_op() crypto: marvell/cesa - use memcpy_fromio()/memcpy_toio() crypto: marvell/cesa - use gfp_t for gfp flags crypto: marvell/cesa - use dma_addr_t for cur_dma crypto: marvell/cesa - use readl_relaxed()/writel_relaxed() crypto: caam - fix indentation of close braces crypto: caam - only export the state we really need to export crypto: caam - fix non-block aligned hash calculation crypto: caam - avoid needlessly saving and restoring caam_hash_ctx crypto: caam - print errno code when hash registration fails crypto: marvell/cesa - fix memory leak crypto: marvell/cesa - fix first-fragment handling in mv_cesa_ahash_dma_last_req() crypto: marvell/cesa - rearrange handling for sw padded hashes ...
Diffstat (limited to 'drivers/char/hw_random')
-rw-r--r--drivers/char/hw_random/Kconfig24
-rw-r--r--drivers/char/hw_random/Makefile2
-rw-r--r--drivers/char/hw_random/core.c2
-rw-r--r--drivers/char/hw_random/exynos-rng.c58
-rw-r--r--drivers/char/hw_random/mxc-rnga.c14
-rw-r--r--drivers/char/hw_random/octeon-rng.c12
-rw-r--r--drivers/char/hw_random/pasemi-rng.c1
-rw-r--r--drivers/char/hw_random/ppc4xx-rng.c1
-rw-r--r--drivers/char/hw_random/st-rng.c151
-rw-r--r--drivers/char/hw_random/stm32-rng.c202
10 files changed, 435 insertions, 32 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index f48cf11c655e..dbf22719462f 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -10,7 +10,7 @@ menuconfig HW_RANDOM
To compile this driver as a module, choose M here: the
module will be called rng-core. This provides a device
- that's usually called /dev/hw_random, and which exposes one
+ that's usually called /dev/hwrng, and which exposes one
of possibly several hardware random number generators.
These hardware random number generators do not feed directly
@@ -346,6 +346,16 @@ config HW_RANDOM_MSM
If unsure, say Y.
+config HW_RANDOM_ST
+ tristate "ST Microelectronics HW Random Number Generator support"
+ depends on HW_RANDOM && ARCH_STI
+ ---help---
+ This driver provides kernel-side support for the Random Number
+ Generator hardware found on STi series of SoCs.
+
+ To compile this driver as a module, choose M here: the
+ module will be called st-rng.
+
config HW_RANDOM_XGENE
tristate "APM X-Gene True Random Number Generator (TRNG) support"
depends on HW_RANDOM && ARCH_XGENE
@@ -359,6 +369,18 @@ config HW_RANDOM_XGENE
If unsure, say Y.
+config HW_RANDOM_STM32
+ tristate "STMicroelectronics STM32 random number generator"
+ depends on HW_RANDOM && (ARCH_STM32 || COMPILE_TEST)
+ help
+ This driver provides kernel-side support for the Random Number
+ Generator hardware found on STM32 microcontrollers.
+
+ To compile this driver as a module, choose M here: the
+ module will be called stm32-rng.
+
+ If unsure, say N.
+
endif # HW_RANDOM
config UML_RANDOM
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 055bb01510ad..5ad397635128 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -30,4 +30,6 @@ obj-$(CONFIG_HW_RANDOM_TPM) += tpm-rng.o
obj-$(CONFIG_HW_RANDOM_BCM2835) += bcm2835-rng.o
obj-$(CONFIG_HW_RANDOM_IPROC_RNG200) += iproc-rng200.o
obj-$(CONFIG_HW_RANDOM_MSM) += msm-rng.o
+obj-$(CONFIG_HW_RANDOM_ST) += st-rng.o
obj-$(CONFIG_HW_RANDOM_XGENE) += xgene-rng.o
+obj-$(CONFIG_HW_RANDOM_STM32) += stm32-rng.o
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index 5643b65cee20..6f497aa1b276 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -323,7 +323,7 @@ static ssize_t hwrng_attr_current_store(struct device *dev,
return -ERESTARTSYS;
err = -ENODEV;
list_for_each_entry(rng, &rng_list, list) {
- if (strcmp(rng->name, buf) == 0) {
+ if (sysfs_streq(rng->name, buf)) {
err = 0;
if (rng != current_rng)
err = set_current_rng(rng);
diff --git a/drivers/char/hw_random/exynos-rng.c b/drivers/char/hw_random/exynos-rng.c
index dc4701fd814f..30cf4623184f 100644
--- a/drivers/char/hw_random/exynos-rng.c
+++ b/drivers/char/hw_random/exynos-rng.c
@@ -53,15 +53,11 @@ static void exynos_rng_writel(struct exynos_rng *rng, u32 val, u32 offset)
__raw_writel(val, rng->mem + offset);
}
-static int exynos_init(struct hwrng *rng)
+static int exynos_rng_configure(struct exynos_rng *exynos_rng)
{
- struct exynos_rng *exynos_rng = container_of(rng,
- struct exynos_rng, rng);
int i;
int ret = 0;
- pm_runtime_get_sync(exynos_rng->dev);
-
for (i = 0 ; i < 5 ; i++)
exynos_rng_writel(exynos_rng, jiffies,
EXYNOS_PRNG_SEED_OFFSET + 4*i);
@@ -70,6 +66,17 @@ static int exynos_init(struct hwrng *rng)
& SEED_SETTING_DONE))
ret = -EIO;
+ return ret;
+}
+
+static int exynos_init(struct hwrng *rng)
+{
+ struct exynos_rng *exynos_rng = container_of(rng,
+ struct exynos_rng, rng);
+ int ret = 0;
+
+ pm_runtime_get_sync(exynos_rng->dev);
+ ret = exynos_rng_configure(exynos_rng);
pm_runtime_put_noidle(exynos_rng->dev);
return ret;
@@ -81,21 +88,24 @@ static int exynos_read(struct hwrng *rng, void *buf,
struct exynos_rng *exynos_rng = container_of(rng,
struct exynos_rng, rng);
u32 *data = buf;
+ int retry = 100;
pm_runtime_get_sync(exynos_rng->dev);
exynos_rng_writel(exynos_rng, PRNG_START, 0);
while (!(exynos_rng_readl(exynos_rng,
- EXYNOS_PRNG_STATUS_OFFSET) & PRNG_DONE))
+ EXYNOS_PRNG_STATUS_OFFSET) & PRNG_DONE) && --retry)
cpu_relax();
+ if (!retry)
+ return -ETIMEDOUT;
exynos_rng_writel(exynos_rng, PRNG_DONE, EXYNOS_PRNG_STATUS_OFFSET);
*data = exynos_rng_readl(exynos_rng, EXYNOS_PRNG_OUT1_OFFSET);
pm_runtime_mark_last_busy(exynos_rng->dev);
- pm_runtime_autosuspend(exynos_rng->dev);
+ pm_runtime_put_sync_autosuspend(exynos_rng->dev);
return 4;
}
@@ -152,15 +162,45 @@ static int exynos_rng_runtime_resume(struct device *dev)
return clk_prepare_enable(exynos_rng->clk);
}
+
+static int exynos_rng_suspend(struct device *dev)
+{
+ return pm_runtime_force_suspend(dev);
+}
+
+static int exynos_rng_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct exynos_rng *exynos_rng = platform_get_drvdata(pdev);
+ int ret;
+
+ ret = pm_runtime_force_resume(dev);
+ if (ret)
+ return ret;
+
+ return exynos_rng_configure(exynos_rng);
+}
#endif
-static UNIVERSAL_DEV_PM_OPS(exynos_rng_pm_ops, exynos_rng_runtime_suspend,
- exynos_rng_runtime_resume, NULL);
+static const struct dev_pm_ops exynos_rng_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(exynos_rng_suspend, exynos_rng_resume)
+ SET_RUNTIME_PM_OPS(exynos_rng_runtime_suspend,
+ exynos_rng_runtime_resume, NULL)
+};
+
+static const struct of_device_id exynos_rng_dt_match[] = {
+ {
+ .compatible = "samsung,exynos4-rng",
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, exynos_rng_dt_match);
static struct platform_driver exynos_rng_driver = {
.driver = {
.name = "exynos-rng",
.pm = &exynos_rng_pm_ops,
+ .of_match_table = exynos_rng_dt_match,
},
.probe = exynos_rng_probe,
};
diff --git a/drivers/char/hw_random/mxc-rnga.c b/drivers/char/hw_random/mxc-rnga.c
index 6cbb72ec6013..467362262651 100644
--- a/drivers/char/hw_random/mxc-rnga.c
+++ b/drivers/char/hw_random/mxc-rnga.c
@@ -141,12 +141,11 @@ static void mxc_rnga_cleanup(struct hwrng *rng)
static int __init mxc_rnga_probe(struct platform_device *pdev)
{
- int err = -ENODEV;
+ int err;
struct resource *res;
struct mxc_rng *mxc_rng;
- mxc_rng = devm_kzalloc(&pdev->dev, sizeof(struct mxc_rng),
- GFP_KERNEL);
+ mxc_rng = devm_kzalloc(&pdev->dev, sizeof(*mxc_rng), GFP_KERNEL);
if (!mxc_rng)
return -ENOMEM;
@@ -160,13 +159,12 @@ static int __init mxc_rnga_probe(struct platform_device *pdev)
mxc_rng->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(mxc_rng->clk)) {
dev_err(&pdev->dev, "Could not get rng_clk!\n");
- err = PTR_ERR(mxc_rng->clk);
- goto out;
+ return PTR_ERR(mxc_rng->clk);
}
err = clk_prepare_enable(mxc_rng->clk);
if (err)
- goto out;
+ return err;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mxc_rng->mem = devm_ioremap_resource(&pdev->dev, res);
@@ -181,14 +179,10 @@ static int __init mxc_rnga_probe(struct platform_device *pdev)
goto err_ioremap;
}
- dev_info(&pdev->dev, "MXC RNGA Registered.\n");
-
return 0;
err_ioremap:
clk_disable_unprepare(mxc_rng->clk);
-
-out:
return err;
}
diff --git a/drivers/char/hw_random/octeon-rng.c b/drivers/char/hw_random/octeon-rng.c
index 6234a4a19b56..8c78aa090492 100644
--- a/drivers/char/hw_random/octeon-rng.c
+++ b/drivers/char/hw_random/octeon-rng.c
@@ -96,7 +96,7 @@ static int octeon_rng_probe(struct platform_device *pdev)
rng->ops = ops;
platform_set_drvdata(pdev, &rng->ops);
- ret = hwrng_register(&rng->ops);
+ ret = devm_hwrng_register(&pdev->dev, &rng->ops);
if (ret)
return -ENOENT;
@@ -105,21 +105,11 @@ static int octeon_rng_probe(struct platform_device *pdev)
return 0;
}
-static int octeon_rng_remove(struct platform_device *pdev)
-{
- struct hwrng *rng = platform_get_drvdata(pdev);
-
- hwrng_unregister(rng);
-
- return 0;
-}
-
static struct platform_driver octeon_rng_driver = {
.driver = {
.name = "octeon_rng",
},
.probe = octeon_rng_probe,
- .remove = octeon_rng_remove,
};
module_platform_driver(octeon_rng_driver);
diff --git a/drivers/char/hw_random/pasemi-rng.c b/drivers/char/hw_random/pasemi-rng.c
index 51cb1d5cc489..699b7259f5d7 100644
--- a/drivers/char/hw_random/pasemi-rng.c
+++ b/drivers/char/hw_random/pasemi-rng.c
@@ -138,6 +138,7 @@ static const struct of_device_id rng_match[] = {
{ .compatible = "pasemi,pwrficient-rng", },
{ },
};
+MODULE_DEVICE_TABLE(of, rng_match);
static struct platform_driver rng_driver = {
.driver = {
diff --git a/drivers/char/hw_random/ppc4xx-rng.c b/drivers/char/hw_random/ppc4xx-rng.c
index b2cfda0fa93e..c0db4387d2e2 100644
--- a/drivers/char/hw_random/ppc4xx-rng.c
+++ b/drivers/char/hw_random/ppc4xx-rng.c
@@ -129,6 +129,7 @@ static const struct of_device_id ppc4xx_rng_match[] = {
{ .compatible = "amcc,ppc440epx-rng", },
{},
};
+MODULE_DEVICE_TABLE(of, ppc4xx_rng_match);
static struct platform_driver ppc4xx_rng_driver = {
.driver = {
diff --git a/drivers/char/hw_random/st-rng.c b/drivers/char/hw_random/st-rng.c
new file mode 100644
index 000000000000..1d35363d23c5
--- /dev/null
+++ b/drivers/char/hw_random/st-rng.c
@@ -0,0 +1,151 @@
+/*
+ * ST Random Number Generator Driver ST's Platforms
+ *
+ * Author: Pankaj Dev: <pankaj.dev@st.com>
+ * 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>
+#include <linux/delay.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* Registers */
+#define ST_RNG_STATUS_REG 0x20
+#define ST_RNG_DATA_REG 0x24
+
+/* Registers fields */
+#define ST_RNG_STATUS_BAD_SEQUENCE BIT(0)
+#define ST_RNG_STATUS_BAD_ALTERNANCE BIT(1)
+#define ST_RNG_STATUS_FIFO_FULL BIT(5)
+
+#define ST_RNG_SAMPLE_SIZE 2 /* 2 Byte (16bit) samples */
+#define ST_RNG_FIFO_DEPTH 4
+#define ST_RNG_FIFO_SIZE (ST_RNG_FIFO_DEPTH * ST_RNG_SAMPLE_SIZE)
+
+/*
+ * Samples are documented to be available every 0.667us, so in theory
+ * the 4 sample deep FIFO should take 2.668us to fill. However, during
+ * thorough testing, it became apparent that filling the FIFO actually
+ * takes closer to 12us. We then multiply by 2 in order to account for
+ * the lack of udelay()'s reliability, suggested by Russell King.
+ */
+#define ST_RNG_FILL_FIFO_TIMEOUT (12 * 2)
+
+struct st_rng_data {
+ void __iomem *base;
+ struct clk *clk;
+ struct hwrng ops;
+};
+
+static int st_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+ struct st_rng_data *ddata = (struct st_rng_data *)rng->priv;
+ u32 status;
+ int i;
+
+ if (max < sizeof(u16))
+ return -EINVAL;
+
+ /* Wait until FIFO is full - max 4uS*/
+ for (i = 0; i < ST_RNG_FILL_FIFO_TIMEOUT; i++) {
+ status = readl_relaxed(ddata->base + ST_RNG_STATUS_REG);
+ if (status & ST_RNG_STATUS_FIFO_FULL)
+ break;
+ udelay(1);
+ }
+
+ if (i == ST_RNG_FILL_FIFO_TIMEOUT)
+ return 0;
+
+ for (i = 0; i < ST_RNG_FIFO_SIZE && i < max; i += 2)
+ *(u16 *)(data + i) =
+ readl_relaxed(ddata->base + ST_RNG_DATA_REG);
+
+ return i; /* No of bytes read */
+}
+
+static int st_rng_probe(struct platform_device *pdev)
+{
+ struct st_rng_data *ddata;
+ struct resource *res;
+ struct clk *clk;
+ void __iomem *base;
+ int ret;
+
+ ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
+ if (!ddata)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ ret = clk_prepare_enable(clk);
+ if (ret)
+ return ret;
+
+ ddata->ops.priv = (unsigned long)ddata;
+ ddata->ops.read = st_rng_read;
+ ddata->ops.name = pdev->name;
+ ddata->base = base;
+ ddata->clk = clk;
+
+ dev_set_drvdata(&pdev->dev, ddata);
+
+ ret = hwrng_register(&ddata->ops);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to register HW RNG\n");
+ return ret;
+ }
+
+ dev_info(&pdev->dev, "Successfully registered HW RNG\n");
+
+ return 0;
+}
+
+static int st_rng_remove(struct platform_device *pdev)
+{
+ struct st_rng_data *ddata = dev_get_drvdata(&pdev->dev);
+
+ hwrng_unregister(&ddata->ops);
+
+ clk_disable_unprepare(ddata->clk);
+
+ return 0;
+}
+
+static const struct of_device_id st_rng_match[] = {
+ { .compatible = "st,rng" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, st_rng_match);
+
+static struct platform_driver st_rng_driver = {
+ .driver = {
+ .name = "st-hwrandom",
+ .of_match_table = of_match_ptr(st_rng_match),
+ },
+ .probe = st_rng_probe,
+ .remove = st_rng_remove
+};
+
+module_platform_driver(st_rng_driver);
+
+MODULE_AUTHOR("Pankaj Dev <pankaj.dev@st.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/char/hw_random/stm32-rng.c b/drivers/char/hw_random/stm32-rng.c
new file mode 100644
index 000000000000..92a810648bd0
--- /dev/null
+++ b/drivers/char/hw_random/stm32-rng.c
@@ -0,0 +1,202 @@
+/*
+ * 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>
+#include <linux/delay.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+#define RNG_CR 0x00
+#define RNG_CR_RNGEN BIT(2)
+
+#define RNG_SR 0x04
+#define RNG_SR_SEIS BIT(6)
+#define RNG_SR_CEIS BIT(5)
+#define RNG_SR_DRDY BIT(0)
+
+#define RNG_DR 0x08
+
+/*
+ * It takes 40 cycles @ 48MHz to generate each random number (e.g. <1us).
+ * At the time of writing STM32 parts max out at ~200MHz meaning a timeout
+ * of 500 leaves us a very comfortable margin for error. The loop to which
+ * the timeout applies takes at least 4 instructions per iteration so the
+ * timeout is enough to take us up to multi-GHz parts!
+ */
+#define RNG_TIMEOUT 500
+
+struct stm32_rng_private {
+ struct hwrng rng;
+ void __iomem *base;
+ struct clk *clk;
+};
+
+static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+ struct stm32_rng_private *priv =
+ container_of(rng, struct stm32_rng_private, rng);
+ u32 sr;
+ int retval = 0;
+
+ pm_runtime_get_sync((struct device *) priv->rng.priv);
+
+ while (max > sizeof(u32)) {
+ sr = readl_relaxed(priv->base + RNG_SR);
+ if (!sr && wait) {
+ unsigned int timeout = RNG_TIMEOUT;
+
+ do {
+ cpu_relax();
+ sr = readl_relaxed(priv->base + RNG_SR);
+ } while (!sr && --timeout);
+ }
+
+ /* If error detected or data not ready... */
+ if (sr != RNG_SR_DRDY)
+ break;
+
+ *(u32 *)data = readl_relaxed(priv->base + RNG_DR);
+
+ retval += sizeof(u32);
+ data += sizeof(u32);
+ max -= sizeof(u32);
+ }
+
+ if (WARN_ONCE(sr & (RNG_SR_SEIS | RNG_SR_CEIS),
+ "bad RNG status - %x\n", sr))
+ writel_relaxed(0, priv->base + RNG_SR);
+
+ pm_runtime_mark_last_busy((struct device *) priv->rng.priv);
+ pm_runtime_put_sync_autosuspend((struct device *) priv->rng.priv);
+
+ return retval || !wait ? retval : -EIO;
+}
+
+static int stm32_rng_init(struct hwrng *rng)
+{
+ struct stm32_rng_private *priv =
+ container_of(rng, struct stm32_rng_private, rng);
+ int err;
+
+ err = clk_prepare_enable(priv->clk);
+ if (err)
+ return err;
+
+ writel_relaxed(RNG_CR_RNGEN, priv->base + RNG_CR);
+
+ /* clear error indicators */
+ writel_relaxed(0, priv->base + RNG_SR);
+
+ return 0;
+}
+
+static void stm32_rng_cleanup(struct hwrng *rng)
+{
+ struct stm32_rng_private *priv =
+ container_of(rng, struct stm32_rng_private, rng);
+
+ writel_relaxed(0, priv->base + RNG_CR);
+ clk_disable_unprepare(priv->clk);
+}
+
+static int stm32_rng_probe(struct platform_device *ofdev)
+{
+ struct device *dev = &ofdev->dev;
+ struct device_node *np = ofdev->dev.of_node;
+ struct stm32_rng_private *priv;
+ struct resource res;
+ int err;
+
+ priv = devm_kzalloc(dev, sizeof(struct stm32_rng_private), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ err = of_address_to_resource(np, 0, &res);
+ if (err)
+ return err;
+
+ priv->base = devm_ioremap_resource(dev, &res);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ priv->clk = devm_clk_get(&ofdev->dev, NULL);
+ if (IS_ERR(priv->clk))
+ return PTR_ERR(priv->clk);
+
+ dev_set_drvdata(dev, priv);
+
+ priv->rng.name = dev_driver_string(dev),
+#ifndef CONFIG_PM
+ priv->rng.init = stm32_rng_init,
+ priv->rng.cleanup = stm32_rng_cleanup,
+#endif
+ priv->rng.read = stm32_rng_read,
+ priv->rng.priv = (unsigned long) dev;
+
+ pm_runtime_set_autosuspend_delay(dev, 100);
+ pm_runtime_use_autosuspend(dev);
+ pm_runtime_enable(dev);
+
+ return devm_hwrng_register(dev, &priv->rng);
+}
+
+#ifdef CONFIG_PM
+static int stm32_rng_runtime_suspend(struct device *dev)
+{
+ struct stm32_rng_private *priv = dev_get_drvdata(dev);
+
+ stm32_rng_cleanup(&priv->rng);
+
+ return 0;
+}
+
+static int stm32_rng_runtime_resume(struct device *dev)
+{
+ struct stm32_rng_private *priv = dev_get_drvdata(dev);
+
+ return stm32_rng_init(&priv->rng);
+}
+#endif
+
+static UNIVERSAL_DEV_PM_OPS(stm32_rng_pm_ops, stm32_rng_runtime_suspend,
+ stm32_rng_runtime_resume, NULL);
+
+static const struct of_device_id stm32_rng_match[] = {
+ {
+ .compatible = "st,stm32-rng",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, stm32_rng_match);
+
+static struct platform_driver stm32_rng_driver = {
+ .driver = {
+ .name = "stm32-rng",
+ .pm = &stm32_rng_pm_ops,
+ .of_match_table = stm32_rng_match,
+ },
+ .probe = stm32_rng_probe,
+};
+
+module_platform_driver(stm32_rng_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Daniel Thompson <daniel.thompson@linaro.org>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 RNG device driver");