[PATCH v2 02/10] drm: bridge: dw_hdmi: Only notify connected status on HPD interrupt

[Neil Armstrong]

On 08/09/2024 15:28, Jonas Karlman wrote:
> drm_helper_hpd_irq_event() and drm_bridge_hpd_notify() may incorrectly
> be called with a connected status when HPD is high and RX sense is
> changed. This typically happen when the HDMI cable is unplugged, shortly
> before the HPD is changed to low.
> 
> Fix this by only notify connected status on the HPD interrupt when HPD
> is going high, not on the RX sense interrupt when RX sense is changed.
> 
> Fixes: da09daf88108 ("drm: bridge: dw_hdmi: only trigger hotplug event on link change")
> Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
> ---
> v2: New patch
> ---
>   drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> index 9e7f86a0bf5c..055fc9848df4 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> @@ -3123,7 +3123,8 @@ static irqreturn_t dw_hdmi_irq(int irq, void *dev_id)
>   			mutex_unlock(&hdmi->cec_notifier_mutex);
>   		}
>   
> -		if (phy_stat & HDMI_PHY_HPD)
> +		if ((intr_stat & HDMI_IH_PHY_STAT0_HPD) &&
> +		    (phy_stat & HDMI_PHY_HPD))
>   			status = connector_status_connected;
>   
>   		if (!(phy_stat & (HDMI_PHY_HPD | HDMI_PHY_RX_SENSE)))

Perhaps this should be also checked for the other lines checking HDMI_PHY_HPD ?

Neil