diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index cc9c60d4facffe..b2d0a3c89fbbfd 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -288,9 +288,103 @@ static void vc4_hdmi_cec_update_clk_div(struct vc4_hdmi *vc4_hdmi) static void vc4_hdmi_cec_update_clk_div(struct vc4_hdmi *vc4_hdmi) {} #endif -static void vc4_hdmi_enable_scrambling(struct drm_encoder *encoder); +static int reset_pipe(struct drm_crtc *crtc, + struct drm_modeset_acquire_ctx *ctx) +{ + struct drm_atomic_state *state; + struct drm_crtc_state *crtc_state; + int ret; + + state = drm_atomic_state_alloc(crtc->dev); + if (!state) + return -ENOMEM; + + state->acquire_ctx = ctx; + + crtc_state = drm_atomic_get_crtc_state(state, crtc); + if (IS_ERR(crtc_state)) { + ret = PTR_ERR(crtc_state); + goto out; + } + + crtc_state->connectors_changed = true; + + ret = drm_atomic_commit(state); +out: + drm_atomic_state_put(state); + + return ret; +} + +static int vc4_hdmi_reset_link(struct drm_connector *connector, + struct drm_modeset_acquire_ctx *ctx) +{ + struct drm_device *drm = connector->dev; + struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector); + struct drm_encoder *encoder = &vc4_hdmi->encoder.base; + struct drm_connector_state *conn_state; + struct drm_crtc_state *crtc_state; + struct drm_crtc *crtc; + bool scrambling_needed; + u8 config; + int ret; + + if (!connector) + return 0; + + ret = drm_modeset_lock(&drm->mode_config.connection_mutex, ctx); + if (ret) + return ret; + + conn_state = connector->state; + crtc = conn_state->crtc; + if (!crtc) + return 0; + + ret = drm_modeset_lock(&crtc->mutex, ctx); + if (ret) + return ret; + + crtc_state = crtc->state; + if (!crtc_state->active) + return 0; + + if (!vc4_hdmi_supports_scrambling(encoder)) + return 0; + + scrambling_needed = vc4_hdmi_mode_needs_scrambling(&vc4_hdmi->saved_adjusted_mode, + vc4_hdmi->output_bpc, + vc4_hdmi->output_format); + if (!scrambling_needed) + return 0; + + if (conn_state->commit && + !try_wait_for_completion(&conn_state->commit->hw_done)) + return 0; + + ret = drm_scdc_readb(connector->ddc, SCDC_TMDS_CONFIG, &config); + if (ret < 0) { + drm_err(drm, "Failed to read TMDS config: %d\n", ret); + return 0; + } + + if (!!(config & SCDC_SCRAMBLING_ENABLE) == scrambling_needed) + return 0; + + /* + * HDMI 2.0 says that one should not send scrambled data + * prior to configuring the sink scrambling, and that + * TMDS clock/data transmission should be suspended when + * changing the TMDS clock rate in the sink. So let's + * just do a full modeset here, even though some sinks + * would be perfectly happy if were to just reconfigure + * the SCDC settings on the fly. + */ + return reset_pipe(crtc, ctx); +} static void vc4_hdmi_handle_hotplug(struct vc4_hdmi *vc4_hdmi, + struct drm_modeset_acquire_ctx *ctx, enum drm_connector_status status) { struct drm_connector *connector = &vc4_hdmi->connector; @@ -303,6 +397,10 @@ static void vc4_hdmi_handle_hotplug(struct vc4_hdmi *vc4_hdmi, * .adap_enable, which leads to that funtion being called with * our mutex held. * + * A similar situation occurs with + * drm_atomic_helper_connector_hdmi_reset_link() that will call + * into our KMS hooks if the scrambling was enabled. + * * Concurrency isn't an issue at the moment since we don't share * any state with any of the other frameworks so we can ignore * the lock for now. @@ -320,7 +418,7 @@ static void vc4_hdmi_handle_hotplug(struct vc4_hdmi *vc4_hdmi, cec_s_phys_addr_from_edid(vc4_hdmi->cec_adap, edid); kfree(edid); - vc4_hdmi_enable_scrambling(&vc4_hdmi->encoder.base.base); + vc4_hdmi_reset_link(connector, ctx); } static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, @@ -352,7 +450,7 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector, status = connector_status_connected; } - vc4_hdmi_handle_hotplug(vc4_hdmi, status); + vc4_hdmi_handle_hotplug(vc4_hdmi, ctx, status); pm_runtime_put(&vc4_hdmi->pdev->dev); return status;