drm/i915: Add support for retrying hotplug

There is some scenarios that we are aware that sink probe can fail,
so lets add the infrastructure to let hotplug() hook to request
another probe after some time.

v2: Handle shared HPD pins (Imre)
v3: Rebased
v4: Renamed INTEL_HOTPLUG_NOCHANGE to INTEL_HOTPLUG_UNCHANGED to keep
it consistent(Rodrigo)
v5: Making the working queue used explicit through all the callers to
hotplug_work (Ville)

Tested-by: Timo Aaltonen <tjaalton@ubuntu.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190712005343.24571-1-jose.souza@intel.com

1 files changed, 9 insertions, 2 deletions

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index e8ecbd55476e..c4016164c34e 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -101,14 +101,21 @@ struct intel_fbdev {
 	struct mutex hpd_lock;
 };
 
+enum intel_hotplug_state {
+	INTEL_HOTPLUG_UNCHANGED,
+	INTEL_HOTPLUG_CHANGED,
+	INTEL_HOTPLUG_RETRY,
+};
+
 struct intel_encoder {
 	struct drm_encoder base;
 
 	enum intel_output_type type;
 	enum port port;
 	unsigned int cloneable;
-	bool (*hotplug)(struct intel_encoder *encoder,
-			struct intel_connector *connector);
+	enum intel_hotplug_state (*hotplug)(struct intel_encoder *encoder,
+					    struct intel_connector *connector,
+					    bool irq_received);
 	enum intel_output_type (*compute_output_type)(struct intel_encoder *,
 						      struct intel_crtc_state *,
 						      struct drm_connector_state *);