Hi Damon,
Am Dienstag, 4. August 2026, 10:17:07 Mitteleuropäische Sommerzeit schrieb
Damon Ding:
> Display-connector mode (DP connector without HPD GPIO):
>
> &edp_out_conn {
> remote-endpoint = <&dp_con_in>;
> };
>
> dp-con {
> compatible = "dp-connector";
> label = "DP OUT";
> type = "full-size";
>
> port {
> dp_con_in: endpoint {
> remote-endpoint = <&edp_out_conn>;
> };
> };
> };
>
> Display-connector mode (DP connector with HPD GPIO):
>
> dp-con {
> compatible = "dp-connector";
> label = "DP OUT";
> type = "full-size";
> pinctrl-0 = <&edp0_hpd>;
> pinctrl-names = "default";
> hpd-gpios = <&gpio4 RK_PC1 GPIO_ACTIVE_HIGH>;
>
> port {
> dp_con_in: endpoint {
> remote-endpoint = <&edp_out_conn>;
> };
> };
> };
>
> All four configurations detect cable plug/unplug events correctly.
hmm, it wasn't working entirely for me though and was still running into
issues when the display was unplugged on boot.
I wiggled around a bit like in the diff below and am now getting correct
plug and unplug events.
But of course, as the dp-variant of the connector does not provide
a "detect" and just the "hpd" functionality, it's missing the initial state.
I'm currently not sure how to find out _if_ a panel is connected on boot.
In other review comments:
- the bridge could use devm_drm_of_get_bridge() as suggested in
the documentation of drm_of_find_panel_or_bridge(), as that would
remove the separate panel_bridge creation
- instead of using plat_data->next_bridge _inside_ the driver
struct drm_bridge has a field next_bridge already.
Heiko
------- 8< -------
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index 877e1b3ca7525..1388640a27de7 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -43,7 +43,7 @@ static const bool verify_fast_training;
static bool analogix_dp_require_pm_for_hpd_irq(struct analogix_dp_device *dp)
{
return analogix_dp_is_rockchip(dp->plat_data->dev_type) &&
!dp->hpd_gpiod &&
- !dp->force_hpd;
+ !dp->hpd_bridge && !dp->force_hpd;
}
static void analogix_dp_init_dp(struct analogix_dp_device *dp)
@@ -72,7 +72,7 @@ static int analogix_dp_detect_hpd(struct analogix_dp_device
*dp)
* Trust connection status from downstream bridge (e.g.,
* display-connector with hpd-gpios).
*/
- if (dp->plat_data->next_bridge && dp->connection_notified)
+ if (dp->hpd_bridge && dp->connection_notified)
return 0;
while (timeout_loop < DP_TIMEOUT_LOOP_COUNT) {
@@ -926,10 +926,10 @@ analogix_dp_bridge_detect(struct drm_bridge *bridge,
struct drm_connector *conne
*/
if (dp->plat_data->next_bridge && dp->last_bridge_is_panel)
status = connector_status_connected;
-
- if (!analogix_dp_detect_hpd(dp))
+ else if (!analogix_dp_detect_hpd(dp))
status = connector_status_connected;
+printk("---> %s status %d\n", __func__, status);
return status;
}
@@ -1044,7 +1044,7 @@ static int analogix_dp_set_bridge(struct
analogix_dp_device *dp)
goto out_dp_init;
}
- if (!analogix_dp_require_pm_for_hpd_irq(dp))
+ if (!analogix_dp_require_pm_for_hpd_irq(dp) && !dp->hpd_bridge)
enable_irq(dp->irq);
return 0;
@@ -1187,7 +1187,7 @@ static void analogix_dp_bridge_disable(struct drm_bridge
*bridge)
if (dp->dpms_mode != DRM_MODE_DPMS_ON)
return;
- if (!analogix_dp_require_pm_for_hpd_irq(dp))
+ if (!analogix_dp_require_pm_for_hpd_irq(dp) && !dp->hpd_bridge)
disable_irq(dp->irq);
analogix_dp_set_analog_power_down(dp, POWER_ALL, 1);
@@ -1264,6 +1264,7 @@ static void analogix_dp_bridge_notify(struct drm_bridge
*bridge, struct drm_conn
struct analogix_dp_device *dp = to_dp(bridge);
dp->connection_notified = (status == connector_status_connected);
+printk("---> %s connection_notified %d\n", __func__, dp->connection_notified);
}
static const struct drm_bridge_funcs analogix_dp_bridge_funcs = {
@@ -1641,6 +1642,13 @@ static int analogix_dp_aux_done_probing(struct
drm_dp_aux *aux)
if (ret && ret != -ENODEV)
return ret;
+ /*
+ * There is a next link in the chain which is not a panel, we should
+ * expect hotplug-information coming from there.
+ */
+ if (plat_data->next_bridge &&
!drm_bridge_is_panel(plat_data->next_bridge))
+ dp->hpd_bridge = true;
+
return component_add(dp->dev, plat_data->ops);
}
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
index d0fb25e543ea0..ecca3b87b4456 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
@@ -169,6 +169,7 @@ struct analogix_dp_device {
bool fast_train_enable;
bool psr_supported;
bool last_bridge_is_panel;
+ bool hpd_bridge;
bool connection_notified;
u8 dpcd[DP_RECEIVER_CAP_SIZE];
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
index ec5950066f838..6f0d642739ffd 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
@@ -182,7 +182,7 @@ void analogix_dp_config_interrupt(struct analogix_dp_device
*dp)
writel(0, dp->reg_base + ANALOGIX_DP_COMMON_INT_MASK_2);
writel(0, dp->reg_base + ANALOGIX_DP_COMMON_INT_MASK_3);
- if (dp->hpd_gpiod) {
+ if (dp->hpd_gpiod || dp->hpd_bridge) {
analogix_dp_mute_hpd_interrupt(dp, HPD_IRQ);
} else {
/*
@@ -438,7 +438,7 @@ void analogix_dp_init_hpd(struct analogix_dp_device *dp)
{
u32 reg;
- if (dp->hpd_gpiod)
+ if (dp->hpd_gpiod || dp->hpd_bridge)
return;
analogix_dp_clear_hotplug_interrupts(dp, HPD_IRQ);
@@ -539,6 +539,9 @@ int analogix_dp_get_plug_in_status(struct
analogix_dp_device *dp)
if (dp->hpd_gpiod) {
if (gpiod_get_value(dp->hpd_gpiod))
return 0;
+ } else if (dp->hpd_bridge) {
+ if (dp->connection_notified)
+ return 0;
} else {
reg = readl(dp->reg_base + ANALOGIX_DP_SYS_CTL_3);
if (reg & HPD_STATUS)
