On June 6, 2025, 9:05, Jani Nikula <[email protected]> wrote: >Allocate and register a drm_panel so that drm_panel_followers can find the >panel. Pass the drm_connector::kdev device to drm_panel allocation for >matching. That's only available after drm_sysfs_connector_add(), so we need to >postpone the drm_panel allocation until .late_register() hook. > >The drm_panel framework is moving towards devm_drm_panel_alloc(). It requires >a wrapper struct, and struct intel_panel would be the natural candidate. >However, we can't postpone its allocation until .late_register(), so we have >to use __devm_drm_panel_alloc() directly for now. > >Call the drm_panel_prepare() and drm_panel_unprepare() functions for >ICL+ DSI, so that followers get notified of the panel power state >changes. This can later be expanded to VLV+ DSI and eDP. > >Cc: Maxime Ripard <[email protected]> >Cc: Heikki Krogerus <[email protected]> >Cc: Lee Shawn C <[email protected]> >Signed-off-by: Jani Nikula <[email protected]>
This patch series was tested on my local device. And panel follower works well on it. Tested-by: Lee Shawn C <[email protected]> >--- > drivers/gpu/drm/i915/display/icl_dsi.c | 4 + > .../drm/i915/display/intel_display_types.h | 4 + > drivers/gpu/drm/i915/display/intel_panel.c | 82 ++++++++++++++++++- > drivers/gpu/drm/i915/display/intel_panel.h | 4 + > 4 files changed, 93 insertions(+), 1 deletion(-) > >diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c >b/drivers/gpu/drm/i915/display/icl_dsi.c >index 026361354e6f..81410b3aed51 100644 >--- a/drivers/gpu/drm/i915/display/icl_dsi.c >+++ b/drivers/gpu/drm/i915/display/icl_dsi.c >@@ -1276,6 +1276,8 @@ static void gen11_dsi_enable(struct intel_atomic_state >*state, > intel_backlight_enable(crtc_state, conn_state); > intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_BACKLIGHT_ON); > >+ intel_panel_prepare(crtc_state, conn_state); >+ > intel_crtc_vblank_on(crtc_state); > } > >@@ -1409,6 +1411,8 @@ static void gen11_dsi_disable(struct intel_atomic_state >*state, { > struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder); > >+ intel_panel_unprepare(old_conn_state); >+ > /* step1: turn off backlight */ > intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_BACKLIGHT_OFF); > intel_backlight_disable(old_conn_state); >diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h >b/drivers/gpu/drm/i915/display/intel_display_types.h >index ed4d743fc7c5..30c7315fc25e 100644 >--- a/drivers/gpu/drm/i915/display/intel_display_types.h >+++ b/drivers/gpu/drm/i915/display/intel_display_types.h >@@ -37,6 +37,7 @@ > #include <drm/drm_crtc.h> > #include <drm/drm_encoder.h> > #include <drm/drm_framebuffer.h> >+#include <drm/drm_panel.h> > #include <drm/drm_rect.h> > #include <drm/drm_vblank_work.h> > #include <drm/intel/i915_hdcp_interface.h> @@ -384,6 +385,9 @@ struct > intel_vbt_panel_data { }; > > struct intel_panel { >+ /* Simple drm_panel */ >+ struct drm_panel *base; >+ > /* Fixed EDID for eDP and LVDS. May hold ERR_PTR for invalid EDID. */ > const struct drm_edid *fixed_edid; > >diff --git a/drivers/gpu/drm/i915/display/intel_panel.c >b/drivers/gpu/drm/i915/display/intel_panel.c >index 5ae302bee191..b1d549e6cf53 100644 >--- a/drivers/gpu/drm/i915/display/intel_panel.c >+++ b/drivers/gpu/drm/i915/display/intel_panel.c >@@ -463,12 +463,92 @@ void intel_panel_fini(struct intel_connector *connector) > } > } > >+const struct drm_panel_funcs dummy_panel_funcs = { }; >+ > int intel_panel_register(struct intel_connector *connector) { >- return intel_backlight_device_register(connector); >+ struct intel_display *display = to_intel_display(connector); >+ struct intel_panel *panel = &connector->panel; >+ int ret; >+ >+ ret = intel_backlight_device_register(connector); >+ if (ret) >+ return ret; >+ >+ if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) { >+ struct device *dev = connector->base.kdev; >+ struct drm_panel *base; >+ >+ /* Sanity check. */ >+ if (drm_WARN_ON(display->drm, !dev)) >+ goto out; >+ >+ /* >+ * We need drm_connector::kdev for allocating the panel, to make >+ * drm_panel_add_follower() lookups work. The kdev is >+ * initialized in drm_sysfs_connector_add(), just before the >+ * connector .late_register() hooks. So we can't allocate the >+ * panel at connector init time, and can't allocate struct >+ * intel_panel with a drm_panel sub-struct. For now, use >+ * __devm_drm_panel_alloc() directly. >+ * >+ * The lookups also depend on drm_connector::fwnode being set in >+ * intel_acpi_assign_connector_fwnodes(). However, if that's >+ * missing, it will gracefully lead to -EPROBE_DEFER in >+ * drm_panel_add_follower(). >+ */ >+ base = __devm_drm_panel_alloc(dev, sizeof(*base), 0, >+ &dummy_panel_funcs, >+ connector->base.connector_type); >+ if (IS_ERR(base)) { >+ ret = PTR_ERR(base); >+ goto err; >+ } >+ >+ panel->base = base; >+ >+ drm_panel_add(panel->base); >+ >+ drm_dbg_kms(display->drm, "[CONNECTOR:%d:%s] Registered panel >device '%s', has fwnode: %s\n", >+ connector->base.base.id, connector->base.name, >+ dev_name(dev), str_yes_no(dev_fwnode(dev))); >+ } >+ >+out: >+ return 0; >+ >+err: >+ intel_backlight_device_unregister(connector); >+ >+ return ret; > } > > void intel_panel_unregister(struct intel_connector *connector) { >+ struct intel_panel *panel = &connector->panel; >+ >+ if (panel->base) >+ drm_panel_remove(panel->base); >+ > intel_backlight_device_unregister(connector); > } >+ >+/* Notify followers, if any, about power being up. */ void >+intel_panel_prepare(const struct intel_crtc_state *crtc_state, >+ const struct drm_connector_state *conn_state) { >+ struct intel_connector *connector = >to_intel_connector(conn_state->connector); >+ struct intel_panel *panel = &connector->panel; >+ >+ drm_panel_prepare(panel->base); >+} >+ >+/* Notify followers, if any, about power going down. */ void >+intel_panel_unprepare(const struct drm_connector_state *old_conn_state) >+{ >+ struct intel_connector *connector = >to_intel_connector(old_conn_state->connector); >+ struct intel_panel *panel = &connector->panel; >+ >+ drm_panel_unprepare(panel->base); >+} >diff --git a/drivers/gpu/drm/i915/display/intel_panel.h >b/drivers/gpu/drm/i915/display/intel_panel.h >index 3d592a4404f3..56a6412cf0fb 100644 >--- a/drivers/gpu/drm/i915/display/intel_panel.h >+++ b/drivers/gpu/drm/i915/display/intel_panel.h >@@ -53,4 +53,8 @@ void intel_panel_add_vbt_sdvo_fixed_mode(struct >intel_connector *connector); void intel_panel_add_encoder_fixed_mode(struct >intel_connector *connector, > struct intel_encoder *encoder); > >+void intel_panel_prepare(const struct intel_crtc_state *crtc_state, >+ const struct drm_connector_state *conn_state); void >+intel_panel_unprepare(const struct drm_connector_state >+*old_conn_state); >+ > #endif /* __INTEL_PANEL_H__ */ >-- >2.39.5 > >
