drm/i915: Init DRM connector polled field early

After an HPD IRQ storm on a connector intel_hpd_irq_storm_detect() will
set the connector's HPD pin state to HPD_MARK_DISABLED and the IRQ gets
disabled. Subsequently intel_hpd_irq_storm_switch_to_polling() will
enable polling for these connectors, setting the pin state to
HPD_DISABLED, but only if the connector's base.polled field is set to
DRM_CONNECTOR_POLL_HPD. intel_hpd_irq_storm_reenable_work() will
reenable the IRQ - after 2 minutes -  if the pin state is HPD_DISABLED.

The connectors will be created with their base.polled field set to 0,
which gets initialized only later in i915_hpd_poll_init_work() (using
intel_connector::polled). If a storm is detected on a connector after
it's created and IRQs are enabled on it - by intel_hpd_init() - and
before its bease.polled field is initialized in the above work, the
connector's HPD pin will stay in the HPD_MARK_DISABLED state - leaving
the IRQ disabled indefinitely - and polling will not get enabled on it as
intended.

I can't see a reason for initializing base.polled in a delayed manner,
so do this already when creating the connector, to prevent the above
race condition.

Link: https://patchwork.freedesktop.org/patch/msgid/20240104083008.2715733-2-imre.deak@intel.com
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_sdvo.c b/drivers/gpu/drm/i915/display/intel_sdvo.c
index 0362d02d70b6..c660dd88dec7 100644
--- a/drivers/gpu/drm/i915/display/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/display/intel_sdvo.c
@@ -2804,6 +2804,7 @@ intel_sdvo_dvi_init(struct intel_sdvo *intel_sdvo, u16 type)
 	} else {
 		intel_connector->polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
 	}
+	intel_connector->base.polled = intel_connector->polled;
 	encoder->encoder_type = DRM_MODE_ENCODER_TMDS;
 	connector->connector_type = DRM_MODE_CONNECTOR_DVID;
 
@@ -2879,6 +2880,7 @@ intel_sdvo_analog_init(struct intel_sdvo *intel_sdvo, u16 type)
 	intel_connector = &intel_sdvo_connector->base;
 	connector = &intel_connector->base;
 	intel_connector->polled = DRM_CONNECTOR_POLL_CONNECT;
+	intel_connector->base.polled = intel_connector->polled;
 	encoder->encoder_type = DRM_MODE_ENCODER_DAC;
 	connector->connector_type = DRM_MODE_CONNECTOR_VGA;