Re: [PATCH 2/2] crypto: qcom-rng: fix support for ACPI-based systems

[Ernesto A. Fernández]

Hi,

thanks for the patch. I have one doubt:

On Wed, Aug 28, 2024 at 09:20:05PM -0400, Brian Masney wrote:
> The qcom-rng driver supports both ACPI and device tree based systems.
> ACPI support was broken when the hw_random interface support was added.
> Let's go ahead and fix this by checking has_acpi_companion().
> 
> This fix was boot tested on a Qualcomm Amberwing server.
> 
> Fixes: f29cd5bb64c2 ("crypto: qcom-rng - Add hw_random interface support")
> Signed-off-by: Brian Masney <bmasney@xxxxxxxxxx>
> ---
>  drivers/crypto/qcom-rng.c | 36 ++++++++++++++++++++----------------
>  1 file changed, 20 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c
> index 4ed545001b77..470062cb258c 100644
> --- a/drivers/crypto/qcom-rng.c
> +++ b/drivers/crypto/qcom-rng.c
> @@ -176,6 +176,21 @@ static struct rng_alg qcom_rng_alg = {
>  	}
>  };
>  
> +static struct qcom_rng_match_data qcom_prng_match_data = {
> +	.skip_init = false,

So with acpi, skip_init will be set to false now, right? But before
f29cd5bb64c2 broke it, skip_init used to be set to true. Was that wrong
before, or now?

Ernesto

> +	.hwrng_support = false,
> +};
> +
> +static struct qcom_rng_match_data qcom_prng_ee_match_data = {
> +	.skip_init = true,
> +	.hwrng_support = false,
> +};
> +
> +static struct qcom_rng_match_data qcom_trng_match_data = {
> +	.skip_init = true,
> +	.hwrng_support = true,
> +};
> +
>  static int qcom_rng_probe(struct platform_device *pdev)
>  {
>  	struct qcom_rng *rng;
> @@ -196,7 +211,11 @@ static int qcom_rng_probe(struct platform_device *pdev)
>  	if (IS_ERR(rng->clk))
>  		return PTR_ERR(rng->clk);
>  
> -	rng->match_data = (struct qcom_rng_match_data *)of_device_get_match_data(&pdev->dev);
> +	if (has_acpi_companion(&pdev->dev))
> +		rng->match_data = &qcom_prng_match_data;
> +	else
> +		rng->match_data =
> +			(struct qcom_rng_match_data *)of_device_get_match_data(&pdev->dev);
>  
>  	qcom_rng_dev = rng;
>  	ret = crypto_register_rng(&qcom_rng_alg);
> @@ -231,21 +250,6 @@ static void qcom_rng_remove(struct platform_device *pdev)
>  	qcom_rng_dev = NULL;
>  }
>  
> -static struct qcom_rng_match_data qcom_prng_match_data = {
> -	.skip_init = false,
> -	.hwrng_support = false,
> -};
> -
> -static struct qcom_rng_match_data qcom_prng_ee_match_data = {
> -	.skip_init = true,
> -	.hwrng_support = false,
> -};
> -
> -static struct qcom_rng_match_data qcom_trng_match_data = {
> -	.skip_init = true,
> -	.hwrng_support = true,
> -};
> -
>  static const struct acpi_device_id __maybe_unused qcom_rng_acpi_match[] = {
>  	{ .id = "QCOM8160", .driver_data = 1 },
>  	{}
> -- 
> 2.46.0
>