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[PATCH v8 6/6] drm/bridge: cadence: cdns-mhdp8546-core: Handle HDCP state in bridge atomic check

Harikrishna Shenoy posted 6 patches 3 months, 4 weeks ago
There is a newer version of this series
[PATCH v8 6/6] drm/bridge: cadence: cdns-mhdp8546-core: Handle HDCP state in bridge atomic check
Posted by Harikrishna Shenoy 3 months, 4 weeks ago 
Now that we have DBANC framework and legacy connector functions removed,
handle the HDCP disabling in bridge atomic check rather than in connector
atomic check in !(DBANC) usecase.

Signed-off-by: Harikrishna Shenoy <h-shenoy@ti.com>
---
 .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
index 06ac5c2ee78f..120eb7ffe20c 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
@@ -1962,6 +1962,10 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
 {
 	struct cdns_mhdp_device *mhdp = bridge_to_mhdp(bridge);
 	const struct drm_display_mode *mode = &crtc_state->adjusted_mode;
+	struct drm_connector_state *old_state, *new_state;
+	struct drm_atomic_state *state = crtc_state->state;
+	struct drm_connector *conn = mhdp->connector;
+	u64 old_cp, new_cp;
 
 	mutex_lock(&mhdp->link_mutex);
 
@@ -1981,6 +1985,25 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
 	if (mhdp->info)
 		bridge_state->input_bus_cfg.flags = *mhdp->info->input_bus_flags;
 
+	if (conn && mhdp->hdcp_supported) {
+		old_state = drm_atomic_get_old_connector_state(state, conn);
+		new_state = drm_atomic_get_new_connector_state(state, conn);
+		old_cp = old_state->content_protection;
+		new_cp = new_state->content_protection;
+
+		if (old_state->hdcp_content_type != new_state->hdcp_content_type &&
+		    new_cp != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
+			new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
+			crtc_state = drm_atomic_get_new_crtc_state(state, new_state->crtc);
+			crtc_state->mode_changed = true;
+		}
+
+		if (!new_state->crtc) {
+			if (old_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED)
+				new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
+		}
+	}
+
 	mutex_unlock(&mhdp->link_mutex);
 	return 0;
 }
-- 
2.34.1
Re: [PATCH v8 6/6] drm/bridge: cadence: cdns-mhdp8546-core: Handle HDCP state in bridge atomic check
Posted by Tomi Valkeinen 2 months, 4 weeks ago 
Hi,

On 14/10/2025 12:45, Harikrishna Shenoy wrote:
> Now that we have DBANC framework and legacy connector functions removed,
> handle the HDCP disabling in bridge atomic check rather than in connector
> atomic check in !(DBANC) usecase.

This sounds odd. The patch is only adding new code, so "handle the HDCP
disabling in bridge atomic check rather than in connector atomic check
in !(DBANC) usecase." doesn't quite make sense.

Afaiu in patch 3 you removed the HDCP code for !DBANC, and here you add
it for DBANC.

Correct me if I'm wrong, but HDCP support for DBANC is currently broken
in upstream, as the HDCP code is only for the !DBANC case?

Isn't this patch then similar to patch 2, which is a fix for a missing
feature with DBANC? So should this also be a fix, and perhaps be moved
as after patch 2?

 Tomi

> Signed-off-by: Harikrishna Shenoy <h-shenoy@ti.com>
> ---
>  .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 23 +++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> index 06ac5c2ee78f..120eb7ffe20c 100644
> --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> @@ -1962,6 +1962,10 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
>  {
>  	struct cdns_mhdp_device *mhdp = bridge_to_mhdp(bridge);
>  	const struct drm_display_mode *mode = &crtc_state->adjusted_mode;
> +	struct drm_connector_state *old_state, *new_state;
> +	struct drm_atomic_state *state = crtc_state->state;
> +	struct drm_connector *conn = mhdp->connector;
> +	u64 old_cp, new_cp;
>  
>  	mutex_lock(&mhdp->link_mutex);
>  
> @@ -1981,6 +1985,25 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
>  	if (mhdp->info)
>  		bridge_state->input_bus_cfg.flags = *mhdp->info->input_bus_flags;
>  
> +	if (conn && mhdp->hdcp_supported) {
> +		old_state = drm_atomic_get_old_connector_state(state, conn);
> +		new_state = drm_atomic_get_new_connector_state(state, conn);
> +		old_cp = old_state->content_protection;
> +		new_cp = new_state->content_protection;
> +
> +		if (old_state->hdcp_content_type != new_state->hdcp_content_type &&
> +		    new_cp != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
> +			new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
> +			crtc_state = drm_atomic_get_new_crtc_state(state, new_state->crtc);
> +			crtc_state->mode_changed = true;
> +		}
> +
> +		if (!new_state->crtc) {
> +			if (old_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED)
> +				new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
> +		}
> +	}
> +
>  	mutex_unlock(&mhdp->link_mutex);
>  	return 0;
>  }
Re: [PATCH v8 6/6] drm/bridge: cadence: cdns-mhdp8546-core: Handle HDCP state in bridge atomic check
Posted by Harikrishna shenoy 2 months, 3 weeks ago 

On 12/11/25 14:52, Tomi Valkeinen wrote:
> Hi,
> 
> On 14/10/2025 12:45, Harikrishna Shenoy wrote:
>> Now that we have DBANC framework and legacy connector functions removed,
>> handle the HDCP disabling in bridge atomic check rather than in connector
>> atomic check in !(DBANC) usecase.
> 
> This sounds odd. The patch is only adding new code, so "handle the HDCP
> disabling in bridge atomic check rather than in connector atomic check
> in !(DBANC) usecase." doesn't quite make sense.
> 
> Afaiu in patch 3 you removed the HDCP code for !DBANC, and here you add
> it for DBANC.
> 
> Correct me if I'm wrong, but HDCP support for DBANC is currently broken
> in upstream, as the HDCP code is only for the !DBANC case?
> 
> Isn't this patch then similar to patch 2, which is a fix for a missing
> feature with DBANC? So should this also be a fix, and perhaps be moved
> as after patch 2?
> 
>   Tomi
> 
Hi Tomi,

Thanks for the review, yes will update the sequence of patch and move 
this after patch 2 and also will add fixes patch.

Regards,
Hari
>> Signed-off-by: Harikrishna Shenoy <h-shenoy@ti.com>
>> ---
>>   .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 23 +++++++++++++++++++
>>   1 file changed, 23 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
>> index 06ac5c2ee78f..120eb7ffe20c 100644
>> --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
>> +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
>> @@ -1962,6 +1962,10 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
>>   {
>>   	struct cdns_mhdp_device *mhdp = bridge_to_mhdp(bridge);
>>   	const struct drm_display_mode *mode = &crtc_state->adjusted_mode;
>> +	struct drm_connector_state *old_state, *new_state;
>> +	struct drm_atomic_state *state = crtc_state->state;
>> +	struct drm_connector *conn = mhdp->connector;
>> +	u64 old_cp, new_cp;
>>   
>>   	mutex_lock(&mhdp->link_mutex);
>>   
>> @@ -1981,6 +1985,25 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
>>   	if (mhdp->info)
>>   		bridge_state->input_bus_cfg.flags = *mhdp->info->input_bus_flags;
>>   
>> +	if (conn && mhdp->hdcp_supported) {
>> +		old_state = drm_atomic_get_old_connector_state(state, conn);
>> +		new_state = drm_atomic_get_new_connector_state(state, conn);
>> +		old_cp = old_state->content_protection;
>> +		new_cp = new_state->content_protection;
>> +
>> +		if (old_state->hdcp_content_type != new_state->hdcp_content_type &&
>> +		    new_cp != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
>> +			new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
>> +			crtc_state = drm_atomic_get_new_crtc_state(state, new_state->crtc);
>> +			crtc_state->mode_changed = true;
>> +		}
>> +
>> +		if (!new_state->crtc) {
>> +			if (old_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED)
>> +				new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
>> +		}
>> +	}
>> +
>>   	mutex_unlock(&mhdp->link_mutex);
>>   	return 0;
>>   }
>

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