On Wed, Aug 13, 2025 at 05:42:29PM +0800, Yongbang Shi wrote:
> From: Baihan Li <libai...@huawei.com>
>
> The debouncing when HPD pulled out still remains sometimes, 200ms still can
> not ensure helper_detect() is correct. So add a flag to hold the sink
> status, and changed detect_ctx() functions by using flag to check status.
THis doesn't explain what is wrong with
drm_connector_helper_detect_from_ddc(). In the end, this function
doesn't use the HPD pin.
>
> Fixes: 3c7623fb5bb6 ("drm/hisilicon/hibmc: Enable this hot plug detect of irq
> feature")
> Signed-off-by: Baihan Li <libai...@huawei.com>
> Signed-off-by: Yongbang Shi <shiyongb...@huawei.com>
> ---
> ChangeLog:
> v3 -> v4:
> - remove link training process in hibmc_dp_detect(), suggested by Dmitry
> Baryshkov.
> - remove if (dev->registered), suggested by Dmitry Baryshkov.
> ---
> drivers/gpu/drm/hisilicon/hibmc/dp/dp_hw.h | 1 +
> .../gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c | 19 ++++++++++++-------
> 2 files changed, 13 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_hw.h
> b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_hw.h
> index 665f5b166dfb..68867475508c 100644
> --- a/drivers/gpu/drm/hisilicon/hibmc/dp/dp_hw.h
> +++ b/drivers/gpu/drm/hisilicon/hibmc/dp/dp_hw.h
> @@ -50,6 +50,7 @@ struct hibmc_dp {
> struct drm_dp_aux aux;
> struct hibmc_dp_cbar_cfg cfg;
> u32 irq_status;
> + int hpd_status;
> };
>
> int hibmc_dp_hw_init(struct hibmc_dp *dp);
> diff --git a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c
> b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c
> index d06832e62e96..ded38530ecda 100644
> --- a/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c
> +++ b/drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_dp.c
> @@ -34,9 +34,12 @@ static int hibmc_dp_connector_get_modes(struct
> drm_connector *connector)
> static int hibmc_dp_detect(struct drm_connector *connector,
> struct drm_modeset_acquire_ctx *ctx, bool force)
> {
> - mdelay(200);
> + struct hibmc_dp *dp = to_hibmc_dp(connector);
>
> - return drm_connector_helper_detect_from_ddc(connector, ctx, force);
> + if (dp->hpd_status)
> + return connector_status_connected;
> + else
> + return connector_status_disconnected;
> }
>
> static const struct drm_connector_helper_funcs hibmc_dp_conn_helper_funcs = {
> @@ -115,21 +118,23 @@ irqreturn_t hibmc_dp_hpd_isr(int irq, void *arg)
> {
> struct drm_device *dev = (struct drm_device *)arg;
> struct hibmc_drm_private *priv = to_hibmc_drm_private(dev);
> + struct hibmc_dp *dp = &priv->dp;
> int idx;
>
> if (!drm_dev_enter(dev, &idx))
> return -ENODEV;
>
> - if (priv->dp.irq_status & DP_MASKED_SINK_HPD_PLUG_INT) {
> + if (((dp->irq_status & DP_MASKED_SINK_HPD_PLUG_INT) &&
> !dp->hpd_status)) {
> drm_dbg_dp(&priv->dev, "HPD IN isr occur!\n");
> - hibmc_dp_hpd_cfg(&priv->dp);
> + hibmc_dp_hpd_cfg(dp);
> + dp->hpd_status = 1;
> } else {
> drm_dbg_dp(&priv->dev, "HPD OUT isr occur!\n");
> - hibmc_dp_reset_link(&priv->dp);
> + hibmc_dp_reset_link(dp);
> + dp->hpd_status = 0;
> }
>
> - if (dev->registered)
> - drm_connector_helper_hpd_irq_event(&priv->dp.connector);
> + drm_connector_helper_hpd_irq_event(&priv->dp.connector);
>
> drm_dev_exit(idx);
>
> --
> 2.33.0
>
--
With best wishes
Dmitry
