[PATCH v3 1/8] dm: rng: Add random number generator(rng) uclass

Ilias Apalodimas
2019-12-13T12:21:24Z

On Fri, Dec 13, 2019 at 12:44:20PM +0530, Sughosh Ganu wrote:
> Add a uclass for reading a random number seed from a random number
> generator device.
>
> Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
> Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
> ---
> drivers/Kconfig | 2 ++
> drivers/Makefile | 1 +
> drivers/rng/Kconfig | 7 +++++++
> drivers/rng/Makefile | 6 ++++++
> drivers/rng/rng-uclass.c | 23 +++++++++++++++++++++++
> include/dm/uclass-id.h | 1 +
> include/rng.h | 30 ++++++++++++++++++++++++++++++
> 7 files changed, 70 insertions(+)
> create mode 100644 drivers/rng/Kconfig
> create mode 100644 drivers/rng/Makefile
> create mode 100644 drivers/rng/rng-uclass.c
> create mode 100644 include/rng.h
>
> diff --git a/drivers/Kconfig b/drivers/Kconfig
> index 9d99ce0..e34a227 100644
> --- a/drivers/Kconfig
> +++ b/drivers/Kconfig
> @@ -90,6 +90,8 @@ source "drivers/remoteproc/Kconfig"
>
> source "drivers/reset/Kconfig"
>
> +source "drivers/rng/Kconfig"
> +
> source "drivers/rtc/Kconfig"
>
> source "drivers/scsi/Kconfig"
> diff --git a/drivers/Makefile b/drivers/Makefile
> index e977f19..6c619b1 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -115,4 +115,5 @@ obj-$(CONFIG_W1_EEPROM) += w1-eeprom/
>
> obj-$(CONFIG_MACH_PIC32) += ddr/microchip/
> obj-$(CONFIG_DM_HWSPINLOCK) += hwspinlock/
> +obj-$(CONFIG_DM_RNG) += rng/
> endif
> diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig
> new file mode 100644
> index 0000000..dd44cc0
> --- /dev/null
> +++ b/drivers/rng/Kconfig
> @@ -0,0 +1,7 @@
> +config DM_RNG
> + bool "Driver support for Random Number Generator devices"
> + depends on DM
> + help
> + Enable driver model for random number generator(rng) devices.
> + This interface is used to initialise the rng device and to
> + read the random seed from the device.
> diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile
> new file mode 100644
> index 0000000..311705b
> --- /dev/null
> +++ b/drivers/rng/Makefile
> @@ -0,0 +1,6 @@
> +# SPDX-License-Identifier: GPL-2.0+
> +#
> +# Copyright (c) 2019, Linaro Limited
> +#
> +
> +obj-$(CONFIG_DM_RNG) += rng-uclass.o
> diff --git a/drivers/rng/rng-uclass.c b/drivers/rng/rng-uclass.c
> new file mode 100644
> index 0000000..b6af3b8
> --- /dev/null
> +++ b/drivers/rng/rng-uclass.c
> @@ -0,0 +1,23 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (c) 2019, Linaro Limited
> + */
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <rng.h>
> +
> +int dm_rng_read(struct udevice *dev, void *buffer, size_t size)
> +{
> + const struct dm_rng_ops *ops = device_get_ops(dev);
> +
> + if (!ops->read)
> + return -ENOSYS;
> +
> + return ops->read(dev, buffer, size);
> +}
> +
> +UCLASS_DRIVER(rng) = {
> + .name = "rng",
> + .id = UCLASS_RNG,
> +};
> diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
> index 0c563d8..192202d 100644
> --- a/include/dm/uclass-id.h
> +++ b/include/dm/uclass-id.h
> @@ -86,6 +86,7 @@ enum uclass_id {
> UCLASS_REGULATOR, /* Regulator device */
> UCLASS_REMOTEPROC, /* Remote Processor device */
> UCLASS_RESET, /* Reset controller device */
> + UCLASS_RNG, /* Random Number Generator */
> UCLASS_RTC, /* Real time clock device */
> UCLASS_SCSI, /* SCSI device */
> UCLASS_SERIAL, /* Serial UART */
> diff --git a/include/rng.h b/include/rng.h
> new file mode 100644
> index 0000000..61d5da9
> --- /dev/null
> +++ b/include/rng.h
> @@ -0,0 +1,30 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (c) 2019, Linaro Limited
> + */
> +
> +#if !defined _RNG_H_
> +#define _RNG_H_
> +
> +#include <dm.h>
> +
> +/**
> + * dm_rng_read() - read a random number seed from the rng device
> + * @buffer: input buffer to put the read random seed into
> + * @size: number of bytes of random seed read
> + *
> + */
> +int dm_rng_read(struct udevice *dev, void *buffer, size_t size);
> +
> +/* struct dm_rng_ops - Operations for the hwrng uclass */
> +struct dm_rng_ops {
> + /**
> + * @read() - read a random number seed
> + *
> + * @data: input buffer to read the random seed
> + * @max: total number of bytes to read
> + */
> + int (*read)(struct udevice *dev, void *data, size_t max);
> +};
> +
> +#endif /* _RNG_H_ */
> --
> 2.7.4
>

Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>