Re: [PATCH v3 3/4] drm/i915: Enable/disable TMDS output buffers in DP++ adaptor as needed

Sharma, Shashank
2016-05-04T10:13:35Z

On 5/3/2016 12:38 AM, ville.syrjala@linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> To save a bit of power, let's try to turn off the TMDS output buffers
> in DP++ adaptors when we're not driving the port.
>
> v2: Let's not forget DDI, toss in a debug message while at it
> v3: Just do the TMDS output control based on adaptor type. With the
> helper getting passed the type, we wouldn't actually have to
> check at all in the driver, but the check eliminates the debug
> output more honest
>
> Cc: stable@vger.kernel.org
> Cc: Tore Anderson <tore@fud.no>
> Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
> Cc: Shashank Sharma <shashank.sharma@intel.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
> drivers/gpu/drm/i915/intel_ddi.c | 12 ++++++++++++
> drivers/gpu/drm/i915/intel_drv.h | 1 +
> drivers/gpu/drm/i915/intel_hdmi.c | 20 ++++++++++++++++++++
> 3 files changed, 33 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
> index 422ec81ef59b..a3600704e6d4 100644
> --- a/drivers/gpu/drm/i915/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/intel_ddi.c
> @@ -1601,6 +1601,12 @@ static void intel_ddi_pre_enable(struct intel_encoder *intel_encoder)
> enum port port = intel_ddi_get_encoder_port(intel_encoder);
> int type = intel_encoder->type;
>
> + if (type == INTEL_OUTPUT_HDMI) {
how to handle type2 active adapters here, which can show type = DP ?
> + struct intel_hdmi *intel_hdmi = enc_to_intel_hdmi(encoder);
> +
> + intel_dp_dual_mode_set_tmds_output(intel_hdmi, true);
> + }
> +
> intel_prepare_ddi_buffer(intel_encoder);
>
> if (type == INTEL_OUTPUT_EDP) {
> @@ -1667,6 +1673,12 @@ static void intel_ddi_post_disable(struct intel_encoder *intel_encoder)
> DPLL_CTRL2_DDI_CLK_OFF(port)));
> else if (INTEL_INFO(dev)->gen < 9)
> I915_WRITE(PORT_CLK_SEL(port), PORT_CLK_SEL_NONE);
> +
> + if (type == INTEL_OUTPUT_HDMI) {
Same as above.

Regards
Shashank
> + struct intel_hdmi *intel_hdmi = enc_to_intel_hdmi(encoder);
> +
> + intel_dp_dual_mode_set_tmds_output(intel_hdmi, false);
> + }
> }
>
> static void intel_enable_ddi(struct intel_encoder *intel_encoder)
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index e94d18fb2ff1..dbcb80c70e2e 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1419,6 +1419,7 @@ void intel_hdmi_init_connector(struct intel_digital_port *intel_dig_port,
> struct intel_hdmi *enc_to_intel_hdmi(struct drm_encoder *encoder);
> bool intel_hdmi_compute_config(struct intel_encoder *encoder,
> struct intel_crtc_state *pipe_config);
> +void intel_dp_dual_mode_set_tmds_output(struct intel_hdmi *hdmi, bool enable);
>
>
> /* intel_lvds.c */
> diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
> index 31ca11134294..c4d93e6b4bed 100644
> --- a/drivers/gpu/drm/i915/intel_hdmi.c
> +++ b/drivers/gpu/drm/i915/intel_hdmi.c
> @@ -836,6 +836,22 @@ static void hsw_set_infoframes(struct drm_encoder *encoder,
> intel_hdmi_set_hdmi_infoframe(encoder, adjusted_mode);
> }
>
> +void intel_dp_dual_mode_set_tmds_output(struct intel_hdmi *hdmi, bool enable)
> +{
> + struct drm_i915_private *dev_priv = to_i915(intel_hdmi_to_dev(hdmi));
> + struct i2c_adapter *adapter =
> + intel_gmbus_get_adapter(dev_priv, hdmi->ddc_bus);
> +
> + if (hdmi->dp_dual_mode.type < DRM_DP_DUAL_MODE_TYPE2_DVI)
> + return;
> +
> + DRM_DEBUG_KMS("%s DP dual mode adaptor TMDS output\n",
> + enable ? "Enabling" : "Disabling");
> +
> + drm_dp_dual_mode_set_tmds_output(hdmi->dp_dual_mode.type,
> + adapter, enable);
> +}
> +
> static void intel_hdmi_prepare(struct intel_encoder *encoder)
> {
> struct drm_device *dev = encoder->base.dev;
> @@ -845,6 +861,8 @@ static void intel_hdmi_prepare(struct intel_encoder *encoder)
> const struct drm_display_mode *adjusted_mode = &crtc->config->base.adjusted_mode;
> u32 hdmi_val;
>
> + intel_dp_dual_mode_set_tmds_output(intel_hdmi, true);
> +
> hdmi_val = SDVO_ENCODING_HDMI;
> if (!HAS_PCH_SPLIT(dev) && crtc->config->limited_color_range)
> hdmi_val |= HDMI_COLOR_RANGE_16_235;
> @@ -1142,6 +1160,8 @@ static void intel_disable_hdmi(struct intel_encoder *encoder)
> }
>
> intel_hdmi->set_infoframes(&encoder->base, false, NULL);
> +
> + intel_dp_dual_mode_set_tmds_output(intel_hdmi, false);
> }
>
> static void g4x_disable_hdmi(struct intel_encoder *encoder)
>