Bridges having the DRM_BRIDGE_OP_HDMI flag set in drm_bridge->ops are
supposed to rely on drm_bridge->supported_formats bitmask to advertise
the supported colorspaces, including HDMI_COLORSPACE_YUV420. Therefore,
the newly introduced drm_bridge->ycbcr_420_allowed flag becomes
redundant in this particular context.
Moreover, when drm_bridge_connector gets initialised, only
drm_bridge->ycbcr_420_allowed is considered in the process of adjusting
the equivalent property of the base drm_connector, which effectively
discards the formats advertised by the HDMI bridge.
Handle the inconsistency by overwriting drm_bridge->ycbcr_420_allowed
for HDMI bridges according to drm_bridge->supported_formats, before
adding them to the global bridge list.
Additionally, ensure the YUV420 related bit is removed from the bitmask
passed to drmm_connector_hdmi_init() when the final ycbcr_420_allowed
flag for the connector ends up not being set (i.e. the case of having at
least one non-HDMI bridge in the pipeline that didn't enable it).
Fixes: 3ced1c687512 ("drm/display: bridge_connector: handle ycbcr_420_allowed")
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
---
drivers/gpu/drm/display/drm_bridge_connector.c | 8 ++++++--
drivers/gpu/drm/drm_bridge.c | 4 ++++
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/display/drm_bridge_connector.c b/drivers/gpu/drm/display/drm_bridge_connector.c
index 320c297008aaa8b6ef5b1f4c71928849b202e8ac..3a5a4f92c979accaa2a8f79ca0f15396dd579429 100644
--- a/drivers/gpu/drm/display/drm_bridge_connector.c
+++ b/drivers/gpu/drm/display/drm_bridge_connector.c
@@ -459,7 +459,10 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
if (connector_type == DRM_MODE_CONNECTOR_Unknown)
return ERR_PTR(-EINVAL);
- if (bridge_connector->bridge_hdmi)
+ if (bridge_connector->bridge_hdmi) {
+ if (!connector->ycbcr_420_allowed)
+ supported_formats &= ~BIT(HDMI_COLORSPACE_YUV420);
+
ret = drmm_connector_hdmi_init(drm, connector,
bridge_connector->bridge_hdmi->vendor,
bridge_connector->bridge_hdmi->product,
@@ -468,10 +471,11 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
connector_type, ddc,
supported_formats,
max_bpc);
- else
+ } else {
ret = drmm_connector_init(drm, connector,
&drm_bridge_connector_funcs,
connector_type, ddc);
+ }
if (ret)
return ERR_PTR(ret);
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index c6af46dd02bfa9e15b59e4c460debdd7fd84be44..241a384ebce39b4a3db58c208af27960904fc662 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -207,6 +207,10 @@ void drm_bridge_add(struct drm_bridge *bridge)
{
mutex_init(&bridge->hpd_mutex);
+ if (bridge->ops & DRM_BRIDGE_OP_HDMI)
+ bridge->ycbcr_420_allowed = !!(bridge->supported_formats &
+ BIT(HDMI_COLORSPACE_YUV420));
+
mutex_lock(&bridge_lock);
list_add_tail(&bridge->list, &bridge_list);
mutex_unlock(&bridge_lock);
--
2.47.0On Tue, Dec 17, 2024 at 12:54:07AM +0200, Cristian Ciocaltea wrote:
> Bridges having the DRM_BRIDGE_OP_HDMI flag set in drm_bridge->ops are
> supposed to rely on drm_bridge->supported_formats bitmask to advertise
> the supported colorspaces, including HDMI_COLORSPACE_YUV420. Therefore,
> the newly introduced drm_bridge->ycbcr_420_allowed flag becomes
> redundant in this particular context.
>
> Moreover, when drm_bridge_connector gets initialised, only
> drm_bridge->ycbcr_420_allowed is considered in the process of adjusting
> the equivalent property of the base drm_connector, which effectively
> discards the formats advertised by the HDMI bridge.
>
> Handle the inconsistency by overwriting drm_bridge->ycbcr_420_allowed
> for HDMI bridges according to drm_bridge->supported_formats, before
> adding them to the global bridge list.
>
> Additionally, ensure the YUV420 related bit is removed from the bitmask
> passed to drmm_connector_hdmi_init() when the final ycbcr_420_allowed
> flag for the connector ends up not being set (i.e. the case of having at
> least one non-HDMI bridge in the pipeline that didn't enable it).
>
> Fixes: 3ced1c687512 ("drm/display: bridge_connector: handle ycbcr_420_allowed")
> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
> ---
> drivers/gpu/drm/display/drm_bridge_connector.c | 8 ++++++--
> drivers/gpu/drm/drm_bridge.c | 4 ++++
> 2 files changed, 10 insertions(+), 2 deletions(-)
I think the second patch in the series is enough, it ensures that
connector's state is consistent, no matter if the drm_bridge_connector
is being used or a normal drm_connector.
Nevertheless, I'd leave the final decision to DRM maintainers.
--
With best wishes
Dmitry
On 12/17/24 1:27 AM, Dmitry Baryshkov wrote:
> On Tue, Dec 17, 2024 at 12:54:07AM +0200, Cristian Ciocaltea wrote:
>> Bridges having the DRM_BRIDGE_OP_HDMI flag set in drm_bridge->ops are
>> supposed to rely on drm_bridge->supported_formats bitmask to advertise
>> the supported colorspaces, including HDMI_COLORSPACE_YUV420. Therefore,
>> the newly introduced drm_bridge->ycbcr_420_allowed flag becomes
>> redundant in this particular context.
>>
>> Moreover, when drm_bridge_connector gets initialised, only
>> drm_bridge->ycbcr_420_allowed is considered in the process of adjusting
>> the equivalent property of the base drm_connector, which effectively
>> discards the formats advertised by the HDMI bridge.
>>
>> Handle the inconsistency by overwriting drm_bridge->ycbcr_420_allowed
>> for HDMI bridges according to drm_bridge->supported_formats, before
>> adding them to the global bridge list.
>>
>> Additionally, ensure the YUV420 related bit is removed from the bitmask
>> passed to drmm_connector_hdmi_init() when the final ycbcr_420_allowed
>> flag for the connector ends up not being set (i.e. the case of having at
>> least one non-HDMI bridge in the pipeline that didn't enable it).
>>
>> Fixes: 3ced1c687512 ("drm/display: bridge_connector: handle ycbcr_420_allowed")
>> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
>> ---
>> drivers/gpu/drm/display/drm_bridge_connector.c | 8 ++++++--
>> drivers/gpu/drm/drm_bridge.c | 4 ++++
>> 2 files changed, 10 insertions(+), 2 deletions(-)
>
> I think the second patch in the series is enough, it ensures that
> connector's state is consistent, no matter if the drm_bridge_connector
> is being used or a normal drm_connector.
>
> Nevertheless, I'd leave the final decision to DRM maintainers.
This patch has 2 parts, maybe I should have put them into separate patches
as they kind of relate to distinct problems.
The 1st part makes sure that drm_bridge->ycbcr_420_allowed is automatically
set when HDMI_COLORSPACE_YUV420 is provided in drm_bridge->supported_formats,
to avoid the need of requiring redundant information on HDMI bridges
initialization. This implicitly ensures the consistency needed to further
allow relying on ->ycbcr_420_allowed internally.
While the 1st part could be dropped (assuming redundancy & consistency is
not really something we want/need to handle), the 2nd part I think is
mandatory, i.e. we must adjust supported_formats before calling
drmm_connector_hdmi_init() to ensure the presence of HDMI_COLORSPACE_YUV420
reflects the status of the computed connector->ycbcr_420_allowed, which
might end up being different than what the HDMI bridge advertised, i.e. the
case of having an HDMI bridge in the pipeline advertising YUV420 via
supported_formats and a non-HDMI one that didn't enable ycbcr_420_allowed.
Thanks,
Cristian
On Tue, Dec 17, 2024 at 02:38:55AM +0200, Cristian Ciocaltea wrote:
> On 12/17/24 1:27 AM, Dmitry Baryshkov wrote:
> > On Tue, Dec 17, 2024 at 12:54:07AM +0200, Cristian Ciocaltea wrote:
> >> Bridges having the DRM_BRIDGE_OP_HDMI flag set in drm_bridge->ops are
> >> supposed to rely on drm_bridge->supported_formats bitmask to advertise
> >> the supported colorspaces, including HDMI_COLORSPACE_YUV420. Therefore,
> >> the newly introduced drm_bridge->ycbcr_420_allowed flag becomes
> >> redundant in this particular context.
> >>
> >> Moreover, when drm_bridge_connector gets initialised, only
> >> drm_bridge->ycbcr_420_allowed is considered in the process of adjusting
> >> the equivalent property of the base drm_connector, which effectively
> >> discards the formats advertised by the HDMI bridge.
> >>
> >> Handle the inconsistency by overwriting drm_bridge->ycbcr_420_allowed
> >> for HDMI bridges according to drm_bridge->supported_formats, before
> >> adding them to the global bridge list.
> >>
> >> Additionally, ensure the YUV420 related bit is removed from the bitmask
> >> passed to drmm_connector_hdmi_init() when the final ycbcr_420_allowed
> >> flag for the connector ends up not being set (i.e. the case of having at
> >> least one non-HDMI bridge in the pipeline that didn't enable it).
> >>
> >> Fixes: 3ced1c687512 ("drm/display: bridge_connector: handle ycbcr_420_allowed")
> >> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
> >> ---
> >> drivers/gpu/drm/display/drm_bridge_connector.c | 8 ++++++--
> >> drivers/gpu/drm/drm_bridge.c | 4 ++++
> >> 2 files changed, 10 insertions(+), 2 deletions(-)
> >
> > I think the second patch in the series is enough, it ensures that
> > connector's state is consistent, no matter if the drm_bridge_connector
> > is being used or a normal drm_connector.
> >
> > Nevertheless, I'd leave the final decision to DRM maintainers.
>
> This patch has 2 parts, maybe I should have put them into separate patches
> as they kind of relate to distinct problems.
>
> The 1st part makes sure that drm_bridge->ycbcr_420_allowed is automatically
> set when HDMI_COLORSPACE_YUV420 is provided in drm_bridge->supported_formats,
> to avoid the need of requiring redundant information on HDMI bridges
> initialization. This implicitly ensures the consistency needed to further
> allow relying on ->ycbcr_420_allowed internally.
>
> While the 1st part could be dropped (assuming redundancy & consistency is
> not really something we want/need to handle), the 2nd part I think is
> mandatory, i.e. we must adjust supported_formats before calling
> drmm_connector_hdmi_init() to ensure the presence of HDMI_COLORSPACE_YUV420
> reflects the status of the computed connector->ycbcr_420_allowed, which
> might end up being different than what the HDMI bridge advertised, i.e. the
> case of having an HDMI bridge in the pipeline advertising YUV420 via
> supported_formats and a non-HDMI one that didn't enable ycbcr_420_allowed.
Please split it into two patches. I don't have a strong opinion upon the
first one (I'd change it to dev_warn() maybe), while the second one
(removing HDMI_COLORSPACE_YUV420 if connector->ycbcr_420_allowed is
false) is definitely a correct change.
>
> Thanks,
> Cristian
--
With best wishes
Dmitry
On 12/20/24 3:05 AM, Dmitry Baryshkov wrote:
> On Tue, Dec 17, 2024 at 02:38:55AM +0200, Cristian Ciocaltea wrote:
>> On 12/17/24 1:27 AM, Dmitry Baryshkov wrote:
>>> On Tue, Dec 17, 2024 at 12:54:07AM +0200, Cristian Ciocaltea wrote:
>>>> Bridges having the DRM_BRIDGE_OP_HDMI flag set in drm_bridge->ops are
>>>> supposed to rely on drm_bridge->supported_formats bitmask to advertise
>>>> the supported colorspaces, including HDMI_COLORSPACE_YUV420. Therefore,
>>>> the newly introduced drm_bridge->ycbcr_420_allowed flag becomes
>>>> redundant in this particular context.
>>>>
>>>> Moreover, when drm_bridge_connector gets initialised, only
>>>> drm_bridge->ycbcr_420_allowed is considered in the process of adjusting
>>>> the equivalent property of the base drm_connector, which effectively
>>>> discards the formats advertised by the HDMI bridge.
>>>>
>>>> Handle the inconsistency by overwriting drm_bridge->ycbcr_420_allowed
>>>> for HDMI bridges according to drm_bridge->supported_formats, before
>>>> adding them to the global bridge list.
>>>>
>>>> Additionally, ensure the YUV420 related bit is removed from the bitmask
>>>> passed to drmm_connector_hdmi_init() when the final ycbcr_420_allowed
>>>> flag for the connector ends up not being set (i.e. the case of having at
>>>> least one non-HDMI bridge in the pipeline that didn't enable it).
>>>>
>>>> Fixes: 3ced1c687512 ("drm/display: bridge_connector: handle ycbcr_420_allowed")
>>>> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
>>>> ---
>>>> drivers/gpu/drm/display/drm_bridge_connector.c | 8 ++++++--
>>>> drivers/gpu/drm/drm_bridge.c | 4 ++++
>>>> 2 files changed, 10 insertions(+), 2 deletions(-)
>>>
>>> I think the second patch in the series is enough, it ensures that
>>> connector's state is consistent, no matter if the drm_bridge_connector
>>> is being used or a normal drm_connector.
>>>
>>> Nevertheless, I'd leave the final decision to DRM maintainers.
>>
>> This patch has 2 parts, maybe I should have put them into separate patches
>> as they kind of relate to distinct problems.
>>
>> The 1st part makes sure that drm_bridge->ycbcr_420_allowed is automatically
>> set when HDMI_COLORSPACE_YUV420 is provided in drm_bridge->supported_formats,
>> to avoid the need of requiring redundant information on HDMI bridges
>> initialization. This implicitly ensures the consistency needed to further
>> allow relying on ->ycbcr_420_allowed internally.
>>
>> While the 1st part could be dropped (assuming redundancy & consistency is
>> not really something we want/need to handle), the 2nd part I think is
>> mandatory, i.e. we must adjust supported_formats before calling
>> drmm_connector_hdmi_init() to ensure the presence of HDMI_COLORSPACE_YUV420
>> reflects the status of the computed connector->ycbcr_420_allowed, which
>> might end up being different than what the HDMI bridge advertised, i.e. the
>> case of having an HDMI bridge in the pipeline advertising YUV420 via
>> supported_formats and a non-HDMI one that didn't enable ycbcr_420_allowed.
>
> Please split it into two patches. I don't have a strong opinion upon the
> first one (I'd change it to dev_warn() maybe), while the second one
> (removing HDMI_COLORSPACE_YUV420 if connector->ycbcr_420_allowed is
> false) is definitely a correct change.
Split done in v4:
https://lore.kernel.org/lkml/20241224-bridge-conn-fmt-prio-v4-2-a9ceb5671379@collabora.com/
Thanks,
Cristian
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