This is a note to let you know that I've just added the patch titled
drm: Add an HPD poll helper to reschedule the poll work
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-add-an-hpd-poll-helper-to-reschedule-the-poll-work.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a94e7ccfc400c024976f3c2f31689ed843498b7c Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak@xxxxxxxxx>
Date: Tue, 22 Aug 2023 14:30:14 +0300
Subject: drm: Add an HPD poll helper to reschedule the poll work
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From: Imre Deak <imre.deak@xxxxxxxxx>
commit a94e7ccfc400c024976f3c2f31689ed843498b7c upstream.
Add a helper to reschedule drm_mode_config::output_poll_work after
polling has been enabled for a connector (and needing a reschedule,
since previously polling was disabled for all connectors and hence
output_poll_work was not running).
This is needed by the next patch fixing HPD polling on i915.
CC: stable@xxxxxxxxxxxxxxx # 6.4+
Cc: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Reviewed-by: Jouni Högander <jouni.hogander@xxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20230822113015.41224-1-imre.deak@xxxxxxxxx
(cherry picked from commit fe2352fd64029918174de4b460dfe6df0c6911cd)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_probe_helper.c | 68 ++++++++++++++++++++----------
include/drm/drm_probe_helper.h | 1 +
2 files changed, 47 insertions(+), 22 deletions(-)
diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index 2fb9bf901a2c..3f479483d7d8 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -262,6 +262,26 @@ static bool drm_kms_helper_enable_hpd(struct drm_device *dev)
}
#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
+static void reschedule_output_poll_work(struct drm_device *dev)
+{
+ unsigned long delay = DRM_OUTPUT_POLL_PERIOD;
+
+ if (dev->mode_config.delayed_event)
+ /*
+ * FIXME:
+ *
+ * Use short (1s) delay to handle the initial delayed event.
+ * This delay should not be needed, but Optimus/nouveau will
+ * fail in a mysterious way if the delayed event is handled as
+ * soon as possible like it is done in
+ * drm_helper_probe_single_connector_modes() in case the poll
+ * was enabled before.
+ */
+ delay = HZ;
+
+ schedule_delayed_work(&dev->mode_config.output_poll_work, delay);
+}
+
/**
* drm_kms_helper_poll_enable - re-enable output polling.
* @dev: drm_device
@@ -279,37 +299,41 @@ static bool drm_kms_helper_enable_hpd(struct drm_device *dev)
*/
void drm_kms_helper_poll_enable(struct drm_device *dev)
{
- bool poll = false;
- unsigned long delay = DRM_OUTPUT_POLL_PERIOD;
-
if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll ||
dev->mode_config.poll_running)
return;
- poll = drm_kms_helper_enable_hpd(dev);
-
- if (dev->mode_config.delayed_event) {
- /*
- * FIXME:
- *
- * Use short (1s) delay to handle the initial delayed event.
- * This delay should not be needed, but Optimus/nouveau will
- * fail in a mysterious way if the delayed event is handled as
- * soon as possible like it is done in
- * drm_helper_probe_single_connector_modes() in case the poll
- * was enabled before.
- */
- poll = true;
- delay = HZ;
- }
-
- if (poll)
- schedule_delayed_work(&dev->mode_config.output_poll_work, delay);
+ if (drm_kms_helper_enable_hpd(dev) ||
+ dev->mode_config.delayed_event)
+ reschedule_output_poll_work(dev);
dev->mode_config.poll_running = true;
}
EXPORT_SYMBOL(drm_kms_helper_poll_enable);
+/**
+ * drm_kms_helper_poll_reschedule - reschedule the output polling work
+ * @dev: drm_device
+ *
+ * This function reschedules the output polling work, after polling for a
+ * connector has been enabled.
+ *
+ * Drivers must call this helper after enabling polling for a connector by
+ * setting %DRM_CONNECTOR_POLL_CONNECT / %DRM_CONNECTOR_POLL_DISCONNECT flags
+ * in drm_connector::polled. Note that after disabling polling by clearing these
+ * flags for a connector will stop the output polling work automatically if
+ * the polling is disabled for all other connectors as well.
+ *
+ * The function can be called only after polling has been enabled by calling
+ * drm_kms_helper_poll_init() / drm_kms_helper_poll_enable().
+ */
+void drm_kms_helper_poll_reschedule(struct drm_device *dev)
+{
+ if (dev->mode_config.poll_running)
+ reschedule_output_poll_work(dev);
+}
+EXPORT_SYMBOL(drm_kms_helper_poll_reschedule);
+
static enum drm_connector_status
drm_helper_probe_detect_ctx(struct drm_connector *connector, bool force)
{
diff --git a/include/drm/drm_probe_helper.h b/include/drm/drm_probe_helper.h
index 4977e0ab72db..fad3c4003b2b 100644
--- a/include/drm/drm_probe_helper.h
+++ b/include/drm/drm_probe_helper.h
@@ -25,6 +25,7 @@ void drm_kms_helper_connector_hotplug_event(struct drm_connector *connector);
void drm_kms_helper_poll_disable(struct drm_device *dev);
void drm_kms_helper_poll_enable(struct drm_device *dev);
+void drm_kms_helper_poll_reschedule(struct drm_device *dev);
bool drm_kms_helper_is_poll_worker(void);
enum drm_mode_status drm_crtc_helper_mode_valid_fixed(struct drm_crtc *crtc,
--
2.42.0
Patches currently in stable-queue which might be from imre.deak@xxxxxxxxx are
queue-6.4/drm-i915-fix-hpd-polling-reenabling-the-output-poll-work-as-needed.patch
queue-6.4/drm-add-an-hpd-poll-helper-to-reschedule-the-poll-work.patch
