[Intel-gfx] [PATCH v2 2/3] drm/i915/hdcp: link hdcp2 recovery on link enc stopped

[Nautiyal, Ankit K]

Looks good to me.

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

On 3/4/2021 2:26 PM, Anshuman Gupta wrote:
> When stream encryption enabling fails due to Link encryption status
> has stopped, prepare HDCP2 for recovery by disabling port authentication
> and encryption such that it can re-attempt port authentication
> and encryption.
>
> Cc: Ramalingam C <ramalingam.c at intel.com>
> Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
> ---
>   drivers/gpu/drm/i915/display/intel_hdcp.c | 13 ++++++++++++-
>   1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
> index 08dd6b46749d..9a70c164c377 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> @@ -1706,6 +1706,7 @@ static int hdcp2_enable_stream_encryption(struct intel_connector *connector)
>   {
>   	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
>   	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct hdcp_port_data *data = &dig_port->hdcp_port_data;
>   	struct intel_hdcp *hdcp = &connector->hdcp;
>   	enum transcoder cpu_transcoder = hdcp->cpu_transcoder;
>   	enum port port = dig_port->base.port;
> @@ -1715,7 +1716,8 @@ static int hdcp2_enable_stream_encryption(struct intel_connector *connector)
>   			    LINK_ENCRYPTION_STATUS)) {
>   		drm_err(&dev_priv->drm, "[%s:%d] HDCP 2.2 Link is not encrypted\n",
>   			connector->base.name, connector->base.base.id);
> -		return -EPERM;
> +		ret = -EPERM;
> +		goto link_recover;
>   	}
>   
>   	if (hdcp->shim->stream_2_2_encryption) {
> @@ -1729,6 +1731,15 @@ static int hdcp2_enable_stream_encryption(struct intel_connector *connector)
>   			    transcoder_name(hdcp->stream_transcoder));
>   	}
>   
> +	return 0;
> +
> +link_recover:
> +	if (hdcp2_deauthenticate_port(connector) < 0)
> +		drm_dbg_kms(&dev_priv->drm, "Port deauth failed.\n");
> +
> +	dig_port->hdcp_auth_status = false;
> +	data->k = 0;
> +
>   	return ret;
>   }
>