Re: [PATCH v2] ath9k: use hw_random API instead of directly dumping into random.c

[Florian Fainelli <f.fainelli@gmail.com>]

On 2/15/2022 4:02 PM, Jason A. Donenfeld wrote:
> Hardware random number generators are supposed to use the hw_random
> framework. This commit turns ath9k's kthread-based design into a proper
> hw_random driver.
> 
> This compiles, but I have no hardware or other ability to determine
> whether it works. I'll leave further development up to the ath9k
> and hw_random maintainers.
> 
> Cc: Toke Høiland-Jørgensen <toke@redhat.com>
> Cc: Kalle Valo <kvalo@kernel.org>
> Cc: Dominik Brodowski <linux@dominikbrodowski.net>
> Cc: Herbert Xu <herbert@gondor.apana.org.au>
> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> ---

[snip]

>   	if (!AR_SREV_9300_20_OR_LATER(ah))
>   		return;
>   
> -	sc->rng_task = kthread_run(ath9k_rng_kthread, sc, "ath9k-hwrng");
> -	if (IS_ERR(sc->rng_task))
> -		sc->rng_task = NULL;
> +	sc->rng_ops.name = "ath9k";

You will have to give this instance an unique name because there can be 
multiple ath9k adapters registered in a given system (like Wi-Fi 
routers), and one of the first thing hwrng_register() does is ensure 
that there is not an existing rng with the same name.

Maybe using a combination of ath9k + dev_name() ought to be unique enough?
-- 
Florian