Since drm_helper_probe_single_connector_modes_merge_bits() and other
places also update connector->status, the output_poll_execute() and/or
drm_helper_hpd_irq_event() logic can get confused and forget to send
a HPD event.
There are two possible solutions: (1) keep track of state at last HPD
check separately, or (2) send events in more places. The latter
approach isn't so convenient to avoid per-connector HPD events (in
case multiple connectors change connection state at the same time) so
I went for the first option.
Signed-off-by: Rob Clark <robdclark at gmail.com>
---
drivers/gpu/drm/drm_crtc.c | 1 +
drivers/gpu/drm/drm_probe_helper.c | 9 ++++++---
include/drm/drm_crtc.h | 9 +++++++++
3 files changed, 16 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 7c1786d..615edee 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -865,6 +865,7 @@ int drm_connector_init(struct drm_device *dev,
INIT_LIST_HEAD(&connector->modes);
connector->edid_blob_ptr = NULL;
connector->status = connector_status_unknown;
+ connector->hpd_status = connector_status_unknown;
drm_connector_get_cmdline_mode(connector);
diff --git a/drivers/gpu/drm/drm_probe_helper.c
b/drivers/gpu/drm/drm_probe_helper.c
index 2fbdcca..c227285 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -293,14 +293,16 @@ static void output_poll_execute(struct work_struct *work)
repoll = true;
- old_status = connector->status;
/* if we are connected and don't want to poll for disconnect
skip it */
- if (old_status == connector_status_connected &&
+ if (connector->status == connector_status_connected &&
!(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))
continue;
+ old_status = connector->hpd_status;
+
connector->status = connector->funcs->detect(connector, false);
+ connector->hpd_status = connector->status;
if (old_status != connector->status) {
const char *old, *new;
@@ -450,9 +452,10 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev)
if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
continue;
- old_status = connector->status;
+ old_status = connector->hpd_status;
connector->status = connector->funcs->detect(connector, false);
+ connector->hpd_status = connector->status;
DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to
%s\n",
connector->base.id,
connector->name,
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index f444263..cb1899b 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -619,6 +619,7 @@ struct drm_encoder {
* @stereo_allowed: can this connector handle stereo modes?
* @modes: modes available on this connector (from fill_modes() + user)
* @status: one of the drm_connector_status enums (connected, not, or unknown)
+ * @hpd_status: status as of last hpd/poll
* @probed_modes: list of modes derived directly from the display
* @display_info: information about attached display (e.g. from EDID)
* @funcs: connector control functions
@@ -676,6 +677,14 @@ struct drm_connector {
enum drm_connector_status status;
+ /* since connector->status can change in various other places
+ * (other than hotplug poll/irq), we need to separately keep
+ * track of the connection status at last should-I-send-an-
+ * hpd-event check, to avoid forgetting to send an hpd event
+ * to userspace
+ */
+ enum drm_connector_status hpd_status;
+
/* these are modes added by probing with DDC or the BIOS */
struct list_head probed_modes;
--
2.1.0
