| Message ID | 1442002110-28733-5-git-send-email-lee.jones@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
Hi Lee, On 11 September 2015 at 21:08, Lee Jones <lee.jones@linaro.org> wrote: > Signed-off-by: Pankaj Dev <pankaj.dev@st.com> > Signed-off-by: Lee Jones <lee.jones@linaro.org> > --- > drivers/char/hw_random/Kconfig | 10 +++ > drivers/char/hw_random/Makefile | 1 + > drivers/char/hw_random/st-rng.c | 142 ++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 153 insertions(+) > create mode 100644 drivers/char/hw_random/st-rng.c > > diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig > index f48cf11..bb6cb77 100644 > --- a/drivers/char/hw_random/Kconfig > +++ b/drivers/char/hw_random/Kconfig > @@ -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 > diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile > index 055bb01..8bcfb45 100644 > --- a/drivers/char/hw_random/Makefile > +++ b/drivers/char/hw_random/Makefile > @@ -30,4 +30,5 @@ 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 > diff --git a/drivers/char/hw_random/st-rng.c b/drivers/char/hw_random/st-rng.c > new file mode 100644 > index 0000000..717a831 > --- /dev/null > +++ b/drivers/char/hw_random/st-rng.c > @@ -0,0 +1,142 @@ > +/* > + * 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_FIFO_SIZE 8 > +#define ST_RNG_SAMPLE_SIZE 2 /* 2 Byte (16bit) samples */ > + > +/* Samples are available every 0.667us, which we round to 1us */ > +#define ST_RNG_FILL_FIFO_TIMEOUT (1 * (ST_RNG_FIFO_SIZE / ST_RNG_SAMPLE_SIZE)) > + > +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); Will this code always be called with max % 2 == 0? ... I.e. will st_rng_read(rng, data[5], 5, waitflg) overflow an array? > + > + return i - 2; /* No of bytes read */ Really? Doesn't this return 0 on st_rng_read(rng, data[2], 2, waitflg); > +} > + > +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)) Are we leaking ddata here ? I.e. before its attached with set_drvdata? > + return PTR_ERR(base); > + > + clk = devm_clk_get(&pdev->dev, NULL); > + if (!clk) And here ... > + return -EINVAL; > + > + clk_prepare_enable(clk); > + > + 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"); > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe devicetree" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Regards Kieran Now available for: $GREATCOMPANY add -A linuxdevs/kieranbingham/ && \ $GREATCOMPANY commit -m "HR: Add fantastic new employee" -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Sep 11, 2015 at 5:08 PM, Lee Jones <lee.jones@linaro.org> wrote: > + 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 (!clk) > + return -EINVAL; This should be: if (IS_ERR(clk)) return PTR_ERR(clk); > + > + clk_prepare_enable(clk); This may fail, so better check its return value and propagate it on error. > + > + 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"); No need to put this info. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, 12 Sep 2015, Fabio Estevam wrote: > On Fri, Sep 11, 2015 at 5:08 PM, Lee Jones <lee.jones@linaro.org> wrote: > > > + 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 (!clk) > > + return -EINVAL; > > This should be: > > if (IS_ERR(clk)) > return PTR_ERR(clk); You're right. Will fix. > > + > > + clk_prepare_enable(clk); > > This may fail, so better check its return value and propagate it on error. Looks like the jury is out on this one. $ git grep clk_prepare_enable | grep '= clk\|if (' | wc -l 659 $ git grep clk_prepare_enable | grep -v '= clk\|if (' | wc -l 569 ... but it's not a problem to fix up. Will do. > > + 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"); > > No need to put this info. Ah, you caught me! I know these types of prints are usually deemed not useful; however, unless there is a failure both this driver and the core driver are silent, so the user doesn't know that 1 or more of these devices are available. I personally like to see an entry in the bootlog for this kind of functionality.
On Sat, 12 Sep 2015, Kieran Bingham wrote: > On 11 September 2015 at 21:08, Lee Jones <lee.jones@linaro.org> wrote: > > Signed-off-by: Pankaj Dev <pankaj.dev@st.com> > > Signed-off-by: Lee Jones <lee.jones@linaro.org> > > --- > > drivers/char/hw_random/Kconfig | 10 +++ > > drivers/char/hw_random/Makefile | 1 + > > drivers/char/hw_random/st-rng.c | 142 ++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 153 insertions(+) > > create mode 100644 drivers/char/hw_random/st-rng.c > > > > diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig > > index f48cf11..bb6cb77 100644 > > --- a/drivers/char/hw_random/Kconfig > > +++ b/drivers/char/hw_random/Kconfig > > @@ -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 > > diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile > > index 055bb01..8bcfb45 100644 > > --- a/drivers/char/hw_random/Makefile > > +++ b/drivers/char/hw_random/Makefile > > @@ -30,4 +30,5 @@ 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 > > diff --git a/drivers/char/hw_random/st-rng.c b/drivers/char/hw_random/st-rng.c > > new file mode 100644 > > index 0000000..717a831 > > --- /dev/null > > +++ b/drivers/char/hw_random/st-rng.c > > @@ -0,0 +1,142 @@ > > +/* > > + * 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_FIFO_SIZE 8 > > +#define ST_RNG_SAMPLE_SIZE 2 /* 2 Byte (16bit) samples */ > > + > > +/* Samples are available every 0.667us, which we round to 1us */ > > +#define ST_RNG_FILL_FIFO_TIMEOUT (1 * (ST_RNG_FIFO_SIZE / ST_RNG_SAMPLE_SIZE)) > > + > > +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); > > Will this code always be called with max % 2 == 0? ... > I.e. will > st_rng_read(rng, data[5], 5, waitflg) > overflow an array? .read() can be called with either 16, 32 or the size of the cache, which is unlikely to be anything !(N^2) (it's 64 in our case). > > + > > + return i - 2; /* No of bytes read */ > > Really? Doesn't this return 0 on st_rng_read(rng, data[2], 2, waitflg); Hmm... I assumed the OA's math was good here. Good spot. I will run some tests to confirm. > > +} > > + > > +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)) > > Are we leaking ddata here ? I.e. before its attached with set_drvdata? It won't leak. That's the point of devm_*. Please see: Documentation/driver-model/devres.txt > > + return PTR_ERR(base); > > + > > + clk = devm_clk_get(&pdev->dev, NULL); > > + if (!clk) > > And here ... Nope. > > + return -EINVAL; > > + > > + clk_prepare_enable(clk); > > + > > + 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/Kconfig b/drivers/char/hw_random/Kconfig index f48cf11..bb6cb77 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -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 diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index 055bb01..8bcfb45 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -30,4 +30,5 @@ 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 diff --git a/drivers/char/hw_random/st-rng.c b/drivers/char/hw_random/st-rng.c new file mode 100644 index 0000000..717a831 --- /dev/null +++ b/drivers/char/hw_random/st-rng.c @@ -0,0 +1,142 @@ +/* + * 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_FIFO_SIZE 8 +#define ST_RNG_SAMPLE_SIZE 2 /* 2 Byte (16bit) samples */ + +/* Samples are available every 0.667us, which we round to 1us */ +#define ST_RNG_FILL_FIFO_TIMEOUT (1 * (ST_RNG_FIFO_SIZE / ST_RNG_SAMPLE_SIZE)) + +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 - 2; /* 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 (!clk) + return -EINVAL; + + clk_prepare_enable(clk); + + 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");