[PATCH] drm: bridge: dw_hdmi: Fix ELD is not updated issue

[PATCH] drm: bridge: dw_hdmi: Fix ELD is not updated issue

[Sandor Yu]

The ELD (EDID-Like Data) is not updated when the HDMI cable
is plugged into different HDMI monitors.
This is because the EDID is not updated in the HDMI HPD function.
As a result, the ELD data remains unchanged and may not reflect
the capabilities of the newly connected HDMI sink device.

To address this issue, the handle_plugged_change function should move to
the bridge_atomic_enable and bridge_atomic_disable functions.
Make sure the EDID is properly updated before updating ELD.

Signed-off-by: Sandor Yu <Sandor.yu@nxp.com>
---
 drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 21 ++++-----------------
 1 file changed, 4 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index 9a3db5234a0e0..6fa4848591226 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -196,7 +196,6 @@ struct dw_hdmi {
 
 	hdmi_codec_plugged_cb plugged_cb;
 	struct device *codec_dev;
-	enum drm_connector_status last_connector_result;
 };
 
 #define HDMI_IH_PHY_STAT0_RX_SENSE \
@@ -235,7 +234,7 @@ int dw_hdmi_set_plugged_cb(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb fn,
 	mutex_lock(&hdmi->mutex);
 	hdmi->plugged_cb = fn;
 	hdmi->codec_dev = codec_dev;
-	plugged = hdmi->last_connector_result == connector_status_connected;
+	plugged = hdmi->connector.status == connector_status_connected;
 	handle_plugged_change(hdmi, plugged);
 	mutex_unlock(&hdmi->mutex);
 
@@ -2446,20 +2445,7 @@ static void dw_hdmi_update_phy_mask(struct dw_hdmi *hdmi)
 
 static enum drm_connector_status dw_hdmi_detect(struct dw_hdmi *hdmi)
 {
-	enum drm_connector_status result;
-
-	result = hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
-
-	mutex_lock(&hdmi->mutex);
-	if (result != hdmi->last_connector_result) {
-		dev_dbg(hdmi->dev, "read_hpd result: %d", result);
-		handle_plugged_change(hdmi,
-				      result == connector_status_connected);
-		hdmi->last_connector_result = result;
-	}
-	mutex_unlock(&hdmi->mutex);
-
-	return result;
+	return hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
 }
 
 static struct edid *dw_hdmi_get_edid(struct dw_hdmi *hdmi,
@@ -2958,6 +2944,7 @@ static void dw_hdmi_bridge_atomic_disable(struct drm_bridge *bridge,
 	hdmi->curr_conn = NULL;
 	dw_hdmi_update_power(hdmi);
 	dw_hdmi_update_phy_mask(hdmi);
+	handle_plugged_change(hdmi, false);
 	mutex_unlock(&hdmi->mutex);
 }
 
@@ -2976,6 +2963,7 @@ static void dw_hdmi_bridge_atomic_enable(struct drm_bridge *bridge,
 	hdmi->curr_conn = connector;
 	dw_hdmi_update_power(hdmi);
 	dw_hdmi_update_phy_mask(hdmi);
+	handle_plugged_change(hdmi, true);
 	mutex_unlock(&hdmi->mutex);
 }
 
@@ -3369,7 +3357,6 @@ struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
 	hdmi->rxsense = true;
 	hdmi->phy_mask = (u8)~(HDMI_PHY_HPD | HDMI_PHY_RX_SENSE);
 	hdmi->mc_clkdis = 0x7f;
-	hdmi->last_connector_result = connector_status_disconnected;
 
 	mutex_init(&hdmi->mutex);
 	mutex_init(&hdmi->audio_mutex);
-- 
2.34.1

Re: [PATCH] drm: bridge: dw_hdmi: Fix ELD is not updated issue

[neil.armstrong]

Hi,

On 26/07/2023 03:48, Sandor Yu wrote:
> The ELD (EDID-Like Data) is not updated when the HDMI cable
> is plugged into different HDMI monitors.
> This is because the EDID is not updated in the HDMI HPD function.
> As a result, the ELD data remains unchanged and may not reflect
> the capabilities of the newly connected HDMI sink device.
> 
> To address this issue, the handle_plugged_change function should move to
> the bridge_atomic_enable and bridge_atomic_disable functions.
> Make sure the EDID is properly updated before updating ELD.
> 
> Signed-off-by: Sandor Yu <Sandor.yu@nxp.com>
> ---
>   drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 21 ++++-----------------
>   1 file changed, 4 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> index 9a3db5234a0e0..6fa4848591226 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> @@ -196,7 +196,6 @@ struct dw_hdmi {
>   
>   	hdmi_codec_plugged_cb plugged_cb;
>   	struct device *codec_dev;
> -	enum drm_connector_status last_connector_result;
>   };
>   
>   #define HDMI_IH_PHY_STAT0_RX_SENSE \
> @@ -235,7 +234,7 @@ int dw_hdmi_set_plugged_cb(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb fn,
>   	mutex_lock(&hdmi->mutex);
>   	hdmi->plugged_cb = fn;
>   	hdmi->codec_dev = codec_dev;
> -	plugged = hdmi->last_connector_result == connector_status_connected;
> +	plugged = hdmi->connector.status == connector_status_connected;

Please use curr_conn instead, connector is not always valid.

>   	handle_plugged_change(hdmi, plugged);
>   	mutex_unlock(&hdmi->mutex);
>   
> @@ -2446,20 +2445,7 @@ static void dw_hdmi_update_phy_mask(struct dw_hdmi *hdmi)
>   
>   static enum drm_connector_status dw_hdmi_detect(struct dw_hdmi *hdmi)
>   {
> -	enum drm_connector_status result;
> -
> -	result = hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
> -
> -	mutex_lock(&hdmi->mutex);
> -	if (result != hdmi->last_connector_result) {
> -		dev_dbg(hdmi->dev, "read_hpd result: %d", result);
> -		handle_plugged_change(hdmi,
> -				      result == connector_status_connected);
> -		hdmi->last_connector_result = result;
> -	}
> -	mutex_unlock(&hdmi->mutex);
> -
> -	return result;
> +	return hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
>   }
>   
>   static struct edid *dw_hdmi_get_edid(struct dw_hdmi *hdmi,
> @@ -2958,6 +2944,7 @@ static void dw_hdmi_bridge_atomic_disable(struct drm_bridge *bridge,
>   	hdmi->curr_conn = NULL;
>   	dw_hdmi_update_power(hdmi);
>   	dw_hdmi_update_phy_mask(hdmi);
> +	handle_plugged_change(hdmi, false);
>   	mutex_unlock(&hdmi->mutex);
>   }
>   
> @@ -2976,6 +2963,7 @@ static void dw_hdmi_bridge_atomic_enable(struct drm_bridge *bridge,
>   	hdmi->curr_conn = connector;
>   	dw_hdmi_update_power(hdmi);
>   	dw_hdmi_update_phy_mask(hdmi);
> +	handle_plugged_change(hdmi, true);
>   	mutex_unlock(&hdmi->mutex);
>   }
>   
> @@ -3369,7 +3357,6 @@ struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
>   	hdmi->rxsense = true;
>   	hdmi->phy_mask = (u8)~(HDMI_PHY_HPD | HDMI_PHY_RX_SENSE);
>   	hdmi->mc_clkdis = 0x7f;
> -	hdmi->last_connector_result = connector_status_disconnected;
>   
>   	mutex_init(&hdmi->mutex);
>   	mutex_init(&hdmi->audio_mutex);

Thanks,
Neil

Re: [PATCH] drm: bridge: dw_hdmi: Fix ELD is not updated issue

[Sandor Yu]

Hi Neil,

Thanks for your comments,
 
> 
> Hi,
> 
> On 26/07/2023 03:48, Sandor Yu wrote:
> > The ELD (EDID-Like Data) is not updated when the HDMI cable is plugged
> > into different HDMI monitors.
> > This is because the EDID is not updated in the HDMI HPD function.
> > As a result, the ELD data remains unchanged and may not reflect the
> > capabilities of the newly connected HDMI sink device.
> >
> > To address this issue, the handle_plugged_change function should move
> > to the bridge_atomic_enable and bridge_atomic_disable functions.
> > Make sure the EDID is properly updated before updating ELD.
> >
> > Signed-off-by: Sandor Yu <Sandor.yu@nxp.com>
> > ---
> >   drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 21 ++++-----------------
> >   1 file changed, 4 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > index 9a3db5234a0e0..6fa4848591226 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > @@ -196,7 +196,6 @@ struct dw_hdmi {
> >
> >       hdmi_codec_plugged_cb plugged_cb;
> >       struct device *codec_dev;
> > -     enum drm_connector_status last_connector_result;
> >   };
> >
> >   #define HDMI_IH_PHY_STAT0_RX_SENSE \ @@ -235,7 +234,7 @@ int
> > dw_hdmi_set_plugged_cb(struct dw_hdmi *hdmi, hdmi_codec_plugged_cb
> fn,
> >       mutex_lock(&hdmi->mutex);
> >       hdmi->plugged_cb = fn;
> >       hdmi->codec_dev = codec_dev;
> > -     plugged = hdmi->last_connector_result ==
> connector_status_connected;
> > +     plugged = hdmi->connector.status == connector_status_connected;
> 
> Please use curr_conn instead, connector is not always valid.
curr_conn is NULL when dw_hdmi_set_plugged_cb is called by dw_hdmi_bridge_atomic_disable.
I will add the variable of last_connector_resul back to driver later.

B.R
Sandor 
> 
> >       handle_plugged_change(hdmi, plugged);
> >       mutex_unlock(&hdmi->mutex);
> >
> > @@ -2446,20 +2445,7 @@ static void dw_hdmi_update_phy_mask(struct
> > dw_hdmi *hdmi)
> >
> >   static enum drm_connector_status dw_hdmi_detect(struct dw_hdmi
> *hdmi)
> >   {
> > -     enum drm_connector_status result;
> > -
> > -     result = hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
> > -
> > -     mutex_lock(&hdmi->mutex);
> > -     if (result != hdmi->last_connector_result) {
> > -             dev_dbg(hdmi->dev, "read_hpd result: %d", result);
> > -             handle_plugged_change(hdmi,
> > -                                   result ==
> connector_status_connected);
> > -             hdmi->last_connector_result = result;
> > -     }
> > -     mutex_unlock(&hdmi->mutex);
> > -
> > -     return result;
> > +     return hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
> >   }
> >
> >   static struct edid *dw_hdmi_get_edid(struct dw_hdmi *hdmi, @@
> > -2958,6 +2944,7 @@ static void dw_hdmi_bridge_atomic_disable(struct
> drm_bridge *bridge,
> >       hdmi->curr_conn = NULL;
> >       dw_hdmi_update_power(hdmi);
> >       dw_hdmi_update_phy_mask(hdmi);
> > +     handle_plugged_change(hdmi, false);
> >       mutex_unlock(&hdmi->mutex);
> >   }
> >
> > @@ -2976,6 +2963,7 @@ static void
> dw_hdmi_bridge_atomic_enable(struct drm_bridge *bridge,
> >       hdmi->curr_conn = connector;
> >       dw_hdmi_update_power(hdmi);
> >       dw_hdmi_update_phy_mask(hdmi);
> > +     handle_plugged_change(hdmi, true);
> >       mutex_unlock(&hdmi->mutex);
> >   }
> >
> > @@ -3369,7 +3357,6 @@ struct dw_hdmi *dw_hdmi_probe(struct
> platform_device *pdev,
> >       hdmi->rxsense = true;
> >       hdmi->phy_mask = (u8)~(HDMI_PHY_HPD |
> HDMI_PHY_RX_SENSE);
> >       hdmi->mc_clkdis = 0x7f;
> > -     hdmi->last_connector_result = connector_status_disconnected;
> >
> >       mutex_init(&hdmi->mutex);
> >       mutex_init(&hdmi->audio_mutex);
> 
> Thanks,
> Neil