drm/i915: Add privacy-screen support (v3)

Add support for eDP panels with a built-in privacy screen using the
new drm_privacy_screen class.

Changes in v3:
- Move drm_privacy_screen_get() call to intel_ddi_init_dp_connector()

Changes in v2:
- Call drm_connector_update_privacy_screen() from
  intel_enable_ddi_dp() / intel_ddi_update_pipe_dp() instead of adding a
  for_each_new_connector_in_state() loop to intel_atomic_commit_tail()
- Move the probe-deferral check to the intel_modeset_probe_defer() helper

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005202322.700909-11-hdegoede@redhat.com

drivers/gpu/drm/i915/display/intel_atomic.c

@@ -139,6 +139,7 @@ int intel_digital_connector_atomic_check(struct drm_connector *conn,
 	    new_conn_state->base.picture_aspect_ratio != old_conn_state->base.picture_aspect_ratio ||
 	    new_conn_state->base.content_type != old_conn_state->base.content_type ||
 	    new_conn_state->base.scaling_mode != old_conn_state->base.scaling_mode ||
+	    new_conn_state->base.privacy_screen_sw_state != old_conn_state->base.privacy_screen_sw_state ||
 	    !drm_connector_atomic_hdr_metadata_equal(old_state, new_state))
 		crtc_state->mode_changed = true;
 

drivers/gpu/drm/i915/display/intel_ddi.c

@@ -25,6 +25,7 @@
  *
  */
 
+#include <drm/drm_privacy_screen_consumer.h>
 #include <drm/drm_scdc_helper.h>
 
 #include "i915_drv.h"
@@ -2905,6 +2906,7 @@ static void intel_enable_ddi_dp(struct intel_atomic_state *state,
 	if (port == PORT_A && DISPLAY_VER(dev_priv) < 9)
 		intel_dp_stop_link_train(intel_dp, crtc_state);
 
+	drm_connector_update_privacy_screen(conn_state);
 	intel_edp_backlight_on(crtc_state, conn_state);
 
 	if (!dig_port->lspcon.active || dig_port->dp.has_hdmi_sink)
@@ -3111,6 +3113,7 @@ static void intel_ddi_update_pipe_dp(struct intel_atomic_state *state,
 	intel_drrs_update(intel_dp, crtc_state);
 
 	intel_backlight_update(state, encoder, crtc_state, conn_state);
+	drm_connector_update_privacy_screen(conn_state);
 }
 
 void intel_ddi_update_pipe(struct intel_atomic_state *state,
@@ -3922,6 +3925,19 @@ intel_ddi_init_dp_connector(struct intel_digital_port *dig_port)
 		return NULL;
 	}
 
+	if (dig_port->base.type == INTEL_OUTPUT_EDP) {
+		struct drm_device *dev = dig_port->base.base.dev;
+		struct drm_privacy_screen *privacy_screen;
+
+		privacy_screen = drm_privacy_screen_get(dev->dev, NULL);
+		if (!IS_ERR(privacy_screen)) {
+			drm_connector_attach_privacy_screen_provider(&connector->base,
+								     privacy_screen);
+		} else if (PTR_ERR(privacy_screen) != -ENODEV) {
+			drm_warn(dev, "Error getting privacy-screen\n");
+		}
+	}
+
 	return connector;
 }
 

drivers/gpu/drm/i915/display/intel_display.c

@@ -42,6 +42,7 @@
 #include <drm/drm_edid.h>
 #include <drm/drm_fourcc.h>
 #include <drm/drm_plane_helper.h>
+#include <drm/drm_privacy_screen_consumer.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_rect.h>
 
@@ -10868,13 +10869,22 @@ void intel_modeset_driver_remove_nogem(struct drm_i915_private *i915)
 
 bool intel_modeset_probe_defer(struct pci_dev *pdev)
 {
+	struct drm_privacy_screen *privacy_screen;
+
 	/*
 	 * apple-gmux is needed on dual GPU MacBook Pro
 	 * to probe the panel if we're the inactive GPU.
 	 */
 	if (vga_switcheroo_client_probe_defer(pdev))
 		return true;
 
+	/* If the LCD panel has a privacy-screen, wait for it */
+	privacy_screen = drm_privacy_screen_get(&pdev->dev, NULL);
+	if (IS_ERR(privacy_screen) && PTR_ERR(privacy_screen) == -EPROBE_DEFER)
+		return true;
+
+	drm_privacy_screen_put(privacy_screen);
+
 	return false;
 }