diff mbox series

[v6,2/3] drm/bridge_connector: stop filtering events in drm_bridge_connector_hpd_cb()

Message ID 20230709202511.287794-3-dmitry.baryshkov@linaro.org
State Superseded
Headers show
Series drm/bridge_connector: implement OOB HPD handling | expand

Commit Message

Dmitry Baryshkov July 9, 2023, 8:25 p.m. UTC
In some cases the bridge drivers would like to receive hotplug events
even in the case new status is equal to the old status. In the DP case
this is used to deliver "attention" messages to the DP host. Stop
filtering the events in the drm_bridge_connector_hpd_cb() and let
drivers decide whether they would like to receive the event or not.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/drm_bridge_connector.c | 5 -----
 1 file changed, 5 deletions(-)

Comments

Janne Grunau July 28, 2023, 6:31 p.m. UTC | #1
On 2023-07-09 23:25:10 +0300, Dmitry Baryshkov wrote:
> In some cases the bridge drivers would like to receive hotplug events
> even in the case new status is equal to the old status. In the DP case
> this is used to deliver "attention" messages to the DP host. Stop
> filtering the events in the drm_bridge_connector_hpd_cb() and let
> drivers decide whether they would like to receive the event or not.

Worth mentioning in the commit message that all current bridges which 
set .hpd_notify appear to be safe w.r.t multiple calls with the same 
status. meson_encoder_hdmi.c will do unnecessary work when called 
repeatedly with status connected. Not sure if it is worth adressing 
since I don't expect multiple calls with connector_status_connected to 
occur for this particular bridge.

Reviewed-By: Janne Grunau <j@jannau.net>

> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  drivers/gpu/drm/drm_bridge_connector.c | 5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_bridge_connector.c b/drivers/gpu/drm/drm_bridge_connector.c
> index 19ae4a177ac3..84d8d310ef04 100644
> --- a/drivers/gpu/drm/drm_bridge_connector.c
> +++ b/drivers/gpu/drm/drm_bridge_connector.c
> @@ -113,16 +113,11 @@ static void drm_bridge_connector_hpd_cb(void *cb_data,
>  	struct drm_bridge_connector *drm_bridge_connector = cb_data;
>  	struct drm_connector *connector = &drm_bridge_connector->base;
>  	struct drm_device *dev = connector->dev;
> -	enum drm_connector_status old_status;
>  
>  	mutex_lock(&dev->mode_config.mutex);
> -	old_status = connector->status;
>  	connector->status = status;
>  	mutex_unlock(&dev->mode_config.mutex);
>  
> -	if (old_status == status)
> -		return;
> -
>  	drm_bridge_connector_hpd_notify(connector, status);
>  
>  	drm_kms_helper_hotplug_event(dev);
> -- 
> 2.39.2
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_bridge_connector.c b/drivers/gpu/drm/drm_bridge_connector.c
index 19ae4a177ac3..84d8d310ef04 100644
--- a/drivers/gpu/drm/drm_bridge_connector.c
+++ b/drivers/gpu/drm/drm_bridge_connector.c
@@ -113,16 +113,11 @@  static void drm_bridge_connector_hpd_cb(void *cb_data,
 	struct drm_bridge_connector *drm_bridge_connector = cb_data;
 	struct drm_connector *connector = &drm_bridge_connector->base;
 	struct drm_device *dev = connector->dev;
-	enum drm_connector_status old_status;
 
 	mutex_lock(&dev->mode_config.mutex);
-	old_status = connector->status;
 	connector->status = status;
 	mutex_unlock(&dev->mode_config.mutex);
 
-	if (old_status == status)
-		return;
-
 	drm_bridge_connector_hpd_notify(connector, status);
 
 	drm_kms_helper_hotplug_event(dev);