drm/i915/panel: register drm_panel and call prepare/unprepare for ICL+ DSI

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 <mripard@kernel.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Lee Shawn C <shawn.c.lee@intel.com>
Tested-by: Lee Shawn C <shawn.c.lee@intel.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/13d15c1414e65ffb21944d66e2820befdab54e98.1749199013.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c
index ca7033251e916b48e6926edd708483c93b915d8f..aa566ad3f5cd72fb8f9440e2645da0047da222b1 100644 (file)
--- 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 d6d0440dcee9b1cc27bd438b0627c04f74f3f2cf..79c328d49ef07b26272bf81a794d6961021cc049 100644 (file)
--- 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 5ae302bee191323f1fcc4274e110fdfcd4856b2c..b1d549e6cf5307b1fb23a081483826ca122bdf87 100644 (file)
--- 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 3d592a4404f37fbdc1c3836ec07a45eb6174a163..56a6412cf0fb1cff3be84b04b22d6673a0bf46f1 100644 (file)
--- 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__ */