Re: [PATCH v11 6/7] firmware: smccc: arm-cca-guest: Bind the TSM provider to an SMCCC device

[Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>]

On Mon, 14 Sep 2026 11:35:10 +0530
"Aneesh Kumar K.V (Arm)" <aneesh.kumar@kernel.org> wrote:

> The Arm CCA guest TSM provider currently binds through the arm-cca-dev
> platform device. Like arm-smccc-trng, this device is not an independent
> platform resource; it is a software representation of the RSI firmware
> service discovered through SMCCC.
> 
> Move RSI discovery into the SMCCC firmware driver. When the SMCCC conduit
> is SMC and if RSI ABI version call is supported, create an arm-rsi-dev
> SMCCC device. Convert the Arm CCA guest TSM provider to an SMCCC driver so
> it binds to that discovered RSI service and keeps module autoloading
> through the SMCCC device id table.
> 
> Keep the old arm-cca-dev platform-device registration for now. Userspace
> has used that device as a Realm-guest indicator, so removing it is left to
> a follow-up patch that adds a replacement sysfs ABI.
> 
> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>

One minor thing inline.
Reviewed-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

> diff --git a/drivers/virt/coco/arm-cca-guest/main.c b/drivers/virt/coco/arm-cca-guest/main.c
> index 80659f0885e9..7b1fa008a8f4 100644
> --- a/drivers/virt/coco/arm-cca-guest/main.c
> +++ b/drivers/virt/coco/arm-cca-guest/main.c
d)
> +static int cca_tsm_probe(struct arm_smccc_device *sdev)
>  {
>  	int ret;
>  
> @@ -178,30 +170,32 @@ static int __init arm_cca_guest_init(void)
>  		return -ENODEV;
>  
>  	ret = tsm_report_register(&arm_cca_tsm_report_ops, NULL);
> -	if (ret < 0)
> -		pr_err("Error %d registering with TSM\n", ret);
> +	if (ret < 0) {
> +		dev_err_probe(&sdev->dev, ret, "Error registering with TSM\n");
> +		return ret;

		return dev_err_probe();

Having that on one line is one of the nicest things about dev_err_probe()


> +	}
>  
> -	return ret;
> +	return 0;
>  }
> -module_init(arm_cca_guest_init);