[PATCH v2 03/12] drm/i915: WARN if HDCP signalling is enabled upon disable

[Ramalingam C]

On 2019-12-12 at 14:02:21 -0500, Sean Paul wrote:
> From: Sean Paul <seanpaul at chromium.org>
> 
> HDCP signalling should not be left on, WARN if it is
LGTM

Reviewed-by: Ramalingam C <ramalingam.c at intel.com>
> 
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Signed-off-by: Sean Paul <seanpaul at chromium.org>
> 
> Changes in v2:
> - Added to the set in lieu of just clearing the bit
> ---
>  drivers/gpu/drm/i915/display/intel_ddi.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index 5b6f32517c75..4a5bdf3ef51d 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -1951,6 +1951,8 @@ void intel_ddi_disable_transcoder_func(const struct intel_crtc_state *crtc_state
>  	i915_reg_t reg = TRANS_DDI_FUNC_CTL(cpu_transcoder);
>  	u32 val = I915_READ(reg);
>  
> +	WARN_ON(val & TRANS_DDI_HDCP_SIGNALLING);
> +
>  	if (INTEL_GEN(dev_priv) >= 12) {
>  		val &= ~(TRANS_DDI_FUNC_ENABLE | TGL_TRANS_DDI_PORT_MASK |
>  			 TRANS_DDI_DP_VC_PAYLOAD_ALLOC);
> -- 
> Sean Paul, Software Engineer, Google / Chromium OS
>