Re: [PATCH 2/2] hwrng: add support for Airoha EN7581 TRNG

[Francesco Dolcini <francesco@dolcini.it>]

On Wed, Oct 16, 2024 at 05:18:42PM +0200, Christian Marangi wrote:
> Add support for Airoha TRNG. The Airoha SoC provide a True RNG module
> that can output 4 bytes of raw data at times.
> 
> The module makes use of various noise source to provide True Random
> Number Generation.
> 
> On probe the module is reset to operate Health Test and verify correct
> execution of it.
> 
> The module can also provide DRBG function but the execution mode is
> mutually exclusive, running as TRNG doesn't permit to also run it as
> DRBG.
> 
> Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> ---
>  drivers/char/hw_random/Kconfig       |  13 ++
>  drivers/char/hw_random/Makefile      |   1 +
>  drivers/char/hw_random/airoha-trng.c | 243 +++++++++++++++++++++++++++
>  3 files changed, 257 insertions(+)
>  create mode 100644 drivers/char/hw_random/airoha-trng.c
> 
> diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
> index 5912c2dd6398..bda283f290bc 100644
> --- a/drivers/char/hw_random/Kconfig
> +++ b/drivers/char/hw_random/Kconfig
> @@ -62,6 +62,19 @@ config HW_RANDOM_AMD
>  
>  	  If unsure, say Y.
>  
> +config HW_RANDOM_AIROHA
> +	tristate "Airoha True HW Random Number Generator support"
> +	depends on ARCH_AIROHA || COMPILE_TEST

> +	default HW_RANDOM
This should not be always enabled when HW_RANDOM is enabled. Enabling
driver should be a opt-in.

Francesco