On Mon, Jun 29, 2026 at 10:14:46PM +0800, Yongxing Mou wrote:
> From: Abhinav Kumar <[email protected]>
>
> Add HPD callback for the MST module which shall be invoked from the
> dp_display's HPD handler to perform MST specific operations in case
> of HPD. In MST case, route the HPD messages to MST module.
>
> Signed-off-by: Abhinav Kumar <[email protected]>
> Signed-off-by: Yongxing Mou <[email protected]>
> ---
> drivers/gpu/drm/msm/dp/dp_display.c | 22 ++++++++++++++----
> drivers/gpu/drm/msm/dp/dp_mst_drm.c | 46
> +++++++++++++++++++++++++++++++++++++
> drivers/gpu/drm/msm/dp/dp_mst_drm.h | 1 +
> 3 files changed, 65 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c
> b/drivers/gpu/drm/msm/dp/dp_display.c
> index 6eac390af2e0..49a7bc5e031e 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -455,6 +455,9 @@ static int msm_dp_hpd_plug_handle(struct
> msm_dp_display_private *dp)
> dp->msm_dp_display.connector_type,
> dp->link->sink_count);
>
> + if (dp->plugged && dp->msm_dp_display.mst_active)
> + return 0;
Why?
> +
> guard(mutex)(&dp->plugged_lock);
>
> ret = pm_runtime_resume_and_get(&pdev->dev);
> @@ -550,12 +553,18 @@ static int msm_dp_irq_hpd_handle(struct
> msm_dp_display_private *dp)
> {
> u32 sink_request;
> int rc = 0;
> + struct msm_dp *msm_dp_display = &dp->msm_dp_display;
>
> /* irq_hpd can happen at either connected or disconnected state */
> drm_dbg_dp(dp->drm_dev, "Before, type=%d, sink_count=%d\n",
> dp->msm_dp_display.connector_type,
> dp->link->sink_count);
>
> + if (msm_dp_display->mst_active) {
> + msm_dp_mst_display_hpd_irq(&dp->msm_dp_display);
This should be routed through the HPD / notifications API so that there
is always a single path for handling the IRQ_HPD interrupts.
> + return 0;
> + }
> +
> /* check for any test request issued by sink */
> rc = msm_dp_link_process_request(dp->link);
> if (!rc) {
> @@ -1111,9 +1120,13 @@ static irqreturn_t msm_dp_display_irq_thread(int irq,
> void *dev_id)
> connector_status_connected);
>
> /* Send HPD as connected and distinguish it in the notifier */
> - if (hpd_isr_status & DP_DP_IRQ_HPD_INT_MASK)
> - drm_bridge_hpd_notify(dp->msm_dp_display.bridge,
> - connector_status_connected);
> + if (hpd_isr_status & DP_DP_IRQ_HPD_INT_MASK) {
> + if (dp->msm_dp_display.mst_active)
Locking? What if MST is being enabled or disabled on the other core?
> + msm_dp_irq_hpd_handle(dp);
> + else
> + drm_bridge_hpd_notify(dp->msm_dp_display.bridge,
> + connector_status_connected);
> + }
>
> ret = IRQ_HANDLED;
>
--
With best wishes
Dmitry
