[PATCH] drm/i915/hdcp: Fix Repeater authentication during topology change

[Nautiyal, Ankit K]

On 12/17/2024 2:07 PM, Suraj Kandpal wrote:
> When topology changes before beginning a new HDCP authentication by
> sending AKE_init message we need to first authenticate only the
> repeater if that fails only then makes sense to enable a new HDCP
> authentication. Even though it made sense to not enable HDCP directly
> from check_link and schedule it repeater authentication needs to be
> done immidieatly

typo: immediately

The first line seems to be overly long.

>
> Fixes: 47ef55a8b784 ("drm/i915/hdcp: Don't enable HDCP2.2 directly from check_link")
> Signed-off-by: Suraj Kandpal <suraj.kandpal at intel.com>

Apart from the nitpicks, patch looks good to me.

Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>


> ---
>   drivers/gpu/drm/i915/display/intel_hdcp.c | 13 +++++++++++++
>   1 file changed, 13 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
> index f6e68a0e3b6d..9ff2274ed7e7 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> @@ -2182,6 +2182,19 @@ static int intel_hdcp2_check_link(struct intel_connector *connector)
>   
>   		drm_dbg_kms(display->drm,
>   			    "HDCP2.2 Downstream topology change\n");
> +
> +		ret = hdcp2_authenticate_repeater_topology(connector);
> +		if (!ret) {
> +			intel_hdcp_update_value(connector,
> +						DRM_MODE_CONTENT_PROTECTION_ENABLED,
> +						true);
> +			goto out;
> +		}
> +
> +		drm_dbg_kms(display->drm,
> +			    "[CONNECTOR:%d:%s] Repeater topology auth failed.(%d)\n",
> +			    connector->base.base.id, connector->base.name,
> +			    ret);
>   	} else {
>   		drm_dbg_kms(display->drm,
>   			    "[CONNECTOR:%d:%s] HDCP2.2 link failed, retrying auth\n",