diff mbox series

[v14,17/28] drm/connector: hdmi: Add Broadcast RGB property

Message ID 20240521-kms-hdmi-connector-state-v14-17-51950db4fedb@kernel.org (mailing list archive)
State New
Headers show
Series drm/connector: Create HDMI Connector infrastructure | expand

Commit Message

Maxime Ripard May 21, 2024, 10:13 a.m. UTC 
The i915 driver has a property to force the RGB range of an HDMI output.
The vc4 driver then implemented the same property with the same
semantics. KWin has support for it, and a PR for mutter is also there to
support it.

Both drivers implementing the same property with the same semantics,
plus the userspace having support for it, is proof enough that it's
pretty much a de-facto standard now and we can provide helpers for it.

Let's plumb it into the newly created HDMI connector.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: Sebastian Wick <sebastian.wick@redhat.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
 Documentation/gpu/kms-properties.csv            |  1 -
 drivers/gpu/drm/display/drm_hdmi_state_helper.c |  4 +-
 drivers/gpu/drm/drm_atomic.c                    |  2 +
 drivers/gpu/drm/drm_atomic_uapi.c               |  4 ++
 drivers/gpu/drm/drm_connector.c                 | 88 +++++++++++++++++++++++++
 include/drm/drm_connector.h                     | 36 ++++++++++
 6 files changed, 133 insertions(+), 2 deletions(-)

Comments

Dmitry Baryshkov May 23, 2024, 10:22 a.m. UTC | #1 
On Tue, May 21, 2024 at 12:13:50PM +0200, Maxime Ripard wrote:
> The i915 driver has a property to force the RGB range of an HDMI output.
> The vc4 driver then implemented the same property with the same
> semantics. KWin has support for it, and a PR for mutter is also there to
> support it.
> 
> Both drivers implementing the same property with the same semantics,
> plus the userspace having support for it, is proof enough that it's
> pretty much a de-facto standard now and we can provide helpers for it.
> 
> Let's plumb it into the newly created HDMI connector.
> 
> Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
> Reviewed-by: Sebastian Wick <sebastian.wick@redhat.com>
> Signed-off-by: Maxime Ripard <mripard@kernel.org>
> ---
>  Documentation/gpu/kms-properties.csv            |  1 -
>  drivers/gpu/drm/display/drm_hdmi_state_helper.c |  4 +-
>  drivers/gpu/drm/drm_atomic.c                    |  2 +
>  drivers/gpu/drm/drm_atomic_uapi.c               |  4 ++
>  drivers/gpu/drm/drm_connector.c                 | 88 +++++++++++++++++++++++++
>  include/drm/drm_connector.h                     | 36 ++++++++++
>  6 files changed, 133 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv
> index 0f9590834829..caef14c532d4 100644
> --- a/Documentation/gpu/kms-properties.csv
> +++ b/Documentation/gpu/kms-properties.csv
> @@ -15,11 +15,10 @@ Owner Module/Drivers,Group,Property Name,Type,Property Values,Object attached,De
>  ,,“saturation”,RANGE,"Min=0, Max=100",Connector,TBD
>  ,,“hue”,RANGE,"Min=0, Max=100",Connector,TBD
>  ,Virtual GPU,“suggested X”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an X offset for a connector
>  ,,“suggested Y”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an Y offset for a connector
>  ,Optional,"""aspect ratio""",ENUM,"{ ""None"", ""4:3"", ""16:9"" }",Connector,TDB
> -i915,Generic,"""Broadcast RGB""",ENUM,"{ ""Automatic"", ""Full"", ""Limited 16:235"" }",Connector,"When this property is set to Limited 16:235 and CTM is set, the hardware will be programmed with the result of the multiplication of CTM by the limited range matrix to ensure the pixels normally in the range 0..1.0 are remapped to the range 16/255..235/255."

Should it still be defined as a generic property?

>  ,,“audio”,ENUM,"{ ""force-dvi"", ""off"", ""auto"", ""on"" }",Connector,TBD
>  ,SDVO-TV,“mode”,ENUM,"{ ""NTSC_M"", ""NTSC_J"", ""NTSC_443"", ""PAL_B"" } etc.",Connector,TBD
>  ,,"""left_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
>  ,,"""right_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
>  ,,"""top_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
> diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
> index 93cb30dba86e..888fe1fe9594 100644


[the rest LGTM]
Maxime Ripard May 27, 2024, 9:02 a.m. UTC | #2 
Hi,

Thanks again for that thorough review :)

On Thu, May 23, 2024 at 01:22:56PM GMT, Dmitry Baryshkov wrote:
> On Tue, May 21, 2024 at 12:13:50PM +0200, Maxime Ripard wrote:
> > The i915 driver has a property to force the RGB range of an HDMI output.
> > The vc4 driver then implemented the same property with the same
> > semantics. KWin has support for it, and a PR for mutter is also there to
> > support it.
> > 
> > Both drivers implementing the same property with the same semantics,
> > plus the userspace having support for it, is proof enough that it's
> > pretty much a de-facto standard now and we can provide helpers for it.
> > 
> > Let's plumb it into the newly created HDMI connector.
> > 
> > Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
> > Reviewed-by: Sebastian Wick <sebastian.wick@redhat.com>
> > Signed-off-by: Maxime Ripard <mripard@kernel.org>
> > ---
> >  Documentation/gpu/kms-properties.csv            |  1 -
> >  drivers/gpu/drm/display/drm_hdmi_state_helper.c |  4 +-
> >  drivers/gpu/drm/drm_atomic.c                    |  2 +
> >  drivers/gpu/drm/drm_atomic_uapi.c               |  4 ++
> >  drivers/gpu/drm/drm_connector.c                 | 88 +++++++++++++++++++++++++
> >  include/drm/drm_connector.h                     | 36 ++++++++++
> >  6 files changed, 133 insertions(+), 2 deletions(-)
> > 
> > diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv
> > index 0f9590834829..caef14c532d4 100644
> > --- a/Documentation/gpu/kms-properties.csv
> > +++ b/Documentation/gpu/kms-properties.csv
> > @@ -15,11 +15,10 @@ Owner Module/Drivers,Group,Property Name,Type,Property Values,Object attached,De
> >  ,,“saturation”,RANGE,"Min=0, Max=100",Connector,TBD
> >  ,,“hue”,RANGE,"Min=0, Max=100",Connector,TBD
> >  ,Virtual GPU,“suggested X”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an X offset for a connector
> >  ,,“suggested Y”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an Y offset for a connector
> >  ,Optional,"""aspect ratio""",ENUM,"{ ""None"", ""4:3"", ""16:9"" }",Connector,TDB
> > -i915,Generic,"""Broadcast RGB""",ENUM,"{ ""Automatic"", ""Full"", ""Limited 16:235"" }",Connector,"When this property is set to Limited 16:235 and CTM is set, the hardware will be programmed with the result of the multiplication of CTM by the limited range matrix to ensure the pixels normally in the range 0..1.0 are remapped to the range 16/255..235/255."
> 
> Should it still be defined as a generic property?

I'm not sure what you mean here, sorry. It's being documented as a
connector property now, so it's very much still listed as a generic
property?

Maxime
Dmitry Baryshkov May 27, 2024, 9:43 a.m. UTC | #3 
On Mon, May 27, 2024 at 11:02:13AM +0200, Maxime Ripard wrote:
> Hi,
> 
> Thanks again for that thorough review :)
> 
> On Thu, May 23, 2024 at 01:22:56PM GMT, Dmitry Baryshkov wrote:
> > On Tue, May 21, 2024 at 12:13:50PM +0200, Maxime Ripard wrote:
> > > The i915 driver has a property to force the RGB range of an HDMI output.
> > > The vc4 driver then implemented the same property with the same
> > > semantics. KWin has support for it, and a PR for mutter is also there to
> > > support it.
> > > 
> > > Both drivers implementing the same property with the same semantics,
> > > plus the userspace having support for it, is proof enough that it's
> > > pretty much a de-facto standard now and we can provide helpers for it.
> > > 
> > > Let's plumb it into the newly created HDMI connector.
> > > 
> > > Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
> > > Reviewed-by: Sebastian Wick <sebastian.wick@redhat.com>
> > > Signed-off-by: Maxime Ripard <mripard@kernel.org>
> > > ---
> > >  Documentation/gpu/kms-properties.csv            |  1 -
> > >  drivers/gpu/drm/display/drm_hdmi_state_helper.c |  4 +-
> > >  drivers/gpu/drm/drm_atomic.c                    |  2 +
> > >  drivers/gpu/drm/drm_atomic_uapi.c               |  4 ++
> > >  drivers/gpu/drm/drm_connector.c                 | 88 +++++++++++++++++++++++++
> > >  include/drm/drm_connector.h                     | 36 ++++++++++
> > >  6 files changed, 133 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv
> > > index 0f9590834829..caef14c532d4 100644
> > > --- a/Documentation/gpu/kms-properties.csv
> > > +++ b/Documentation/gpu/kms-properties.csv
> > > @@ -15,11 +15,10 @@ Owner Module/Drivers,Group,Property Name,Type,Property Values,Object attached,De
> > >  ,,“saturation”,RANGE,"Min=0, Max=100",Connector,TBD
> > >  ,,“hue”,RANGE,"Min=0, Max=100",Connector,TBD
> > >  ,Virtual GPU,“suggested X”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an X offset for a connector
> > >  ,,“suggested Y”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an Y offset for a connector
> > >  ,Optional,"""aspect ratio""",ENUM,"{ ""None"", ""4:3"", ""16:9"" }",Connector,TDB
> > > -i915,Generic,"""Broadcast RGB""",ENUM,"{ ""Automatic"", ""Full"", ""Limited 16:235"" }",Connector,"When this property is set to Limited 16:235 and CTM is set, the hardware will be programmed with the result of the multiplication of CTM by the limited range matrix to ensure the pixels normally in the range 0..1.0 are remapped to the range 16/255..235/255."
> > 
> > Should it still be defined as a generic property?
> 
> I'm not sure what you mean here, sorry. It's being documented as a
> connector property now, so it's very much still listed as a generic
> property?

I didn't perform my duty well enough and I didn't check the file for
other instances of the property. Now I indeed see a generic "Broadcast
RGB" property, but to me it looks like having a different set of values:

,,"""Broadcast RGB""",ENUM,"{ “off”, “auto”, “on” }",Connector,TBD
Maxime Ripard May 27, 2024, 1:30 p.m. UTC | #4 
Hi,

On Mon, May 27, 2024 at 12:43:18PM GMT, Dmitry Baryshkov wrote:
> On Mon, May 27, 2024 at 11:02:13AM +0200, Maxime Ripard wrote:
> > Hi,
> > 
> > Thanks again for that thorough review :)
> > 
> > On Thu, May 23, 2024 at 01:22:56PM GMT, Dmitry Baryshkov wrote:
> > > On Tue, May 21, 2024 at 12:13:50PM +0200, Maxime Ripard wrote:
> > > > The i915 driver has a property to force the RGB range of an HDMI output.
> > > > The vc4 driver then implemented the same property with the same
> > > > semantics. KWin has support for it, and a PR for mutter is also there to
> > > > support it.
> > > > 
> > > > Both drivers implementing the same property with the same semantics,
> > > > plus the userspace having support for it, is proof enough that it's
> > > > pretty much a de-facto standard now and we can provide helpers for it.
> > > > 
> > > > Let's plumb it into the newly created HDMI connector.
> > > > 
> > > > Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
> > > > Reviewed-by: Sebastian Wick <sebastian.wick@redhat.com>
> > > > Signed-off-by: Maxime Ripard <mripard@kernel.org>
> > > > ---
> > > >  Documentation/gpu/kms-properties.csv            |  1 -
> > > >  drivers/gpu/drm/display/drm_hdmi_state_helper.c |  4 +-
> > > >  drivers/gpu/drm/drm_atomic.c                    |  2 +
> > > >  drivers/gpu/drm/drm_atomic_uapi.c               |  4 ++
> > > >  drivers/gpu/drm/drm_connector.c                 | 88 +++++++++++++++++++++++++
> > > >  include/drm/drm_connector.h                     | 36 ++++++++++
> > > >  6 files changed, 133 insertions(+), 2 deletions(-)
> > > > 
> > > > diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv
> > > > index 0f9590834829..caef14c532d4 100644
> > > > --- a/Documentation/gpu/kms-properties.csv
> > > > +++ b/Documentation/gpu/kms-properties.csv
> > > > @@ -15,11 +15,10 @@ Owner Module/Drivers,Group,Property Name,Type,Property Values,Object attached,De
> > > >  ,,“saturation”,RANGE,"Min=0, Max=100",Connector,TBD
> > > >  ,,“hue”,RANGE,"Min=0, Max=100",Connector,TBD
> > > >  ,Virtual GPU,“suggested X”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an X offset for a connector
> > > >  ,,“suggested Y”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an Y offset for a connector
> > > >  ,Optional,"""aspect ratio""",ENUM,"{ ""None"", ""4:3"", ""16:9"" }",Connector,TDB
> > > > -i915,Generic,"""Broadcast RGB""",ENUM,"{ ""Automatic"", ""Full"", ""Limited 16:235"" }",Connector,"When this property is set to Limited 16:235 and CTM is set, the hardware will be programmed with the result of the multiplication of CTM by the limited range matrix to ensure the pixels normally in the range 0..1.0 are remapped to the range 16/255..235/255."
> > > 
> > > Should it still be defined as a generic property?
> > 
> > I'm not sure what you mean here, sorry. It's being documented as a
> > connector property now, so it's very much still listed as a generic
> > property?
> 
> I didn't perform my duty well enough and I didn't check the file for
> other instances of the property. Now I indeed see a generic "Broadcast
> RGB" property, but to me it looks like having a different set of values:
> 
> ,,"""Broadcast RGB""",ENUM,"{ “off”, “auto”, “on” }",Connector,TBD

That's not really what I meant: that file is deprecated now and it's not
where we document the properties anymore. This patch has improved that
documentation and moved it to the new place, and removed the deprecated
part.

However, this line shouldn't be there at all. I'll add a patch to remove
it.

Thanks!
Maxime
Dmitry Baryshkov May 27, 2024, 7 p.m. UTC | #5 
On Mon, 27 May 2024 at 16:30, Maxime Ripard <mripard@kernel.org> wrote:
>
> Hi,
>
> On Mon, May 27, 2024 at 12:43:18PM GMT, Dmitry Baryshkov wrote:
> > On Mon, May 27, 2024 at 11:02:13AM +0200, Maxime Ripard wrote:
> > > Hi,
> > >
> > > Thanks again for that thorough review :)
> > >
> > > On Thu, May 23, 2024 at 01:22:56PM GMT, Dmitry Baryshkov wrote:
> > > > On Tue, May 21, 2024 at 12:13:50PM +0200, Maxime Ripard wrote:
> > > > > The i915 driver has a property to force the RGB range of an HDMI output.
> > > > > The vc4 driver then implemented the same property with the same
> > > > > semantics. KWin has support for it, and a PR for mutter is also there to
> > > > > support it.
> > > > >
> > > > > Both drivers implementing the same property with the same semantics,
> > > > > plus the userspace having support for it, is proof enough that it's
> > > > > pretty much a de-facto standard now and we can provide helpers for it.
> > > > >
> > > > > Let's plumb it into the newly created HDMI connector.
> > > > >
> > > > > Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > > Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
> > > > > Reviewed-by: Sebastian Wick <sebastian.wick@redhat.com>
> > > > > Signed-off-by: Maxime Ripard <mripard@kernel.org>
> > > > > ---
> > > > >  Documentation/gpu/kms-properties.csv            |  1 -
> > > > >  drivers/gpu/drm/display/drm_hdmi_state_helper.c |  4 +-
> > > > >  drivers/gpu/drm/drm_atomic.c                    |  2 +
> > > > >  drivers/gpu/drm/drm_atomic_uapi.c               |  4 ++
> > > > >  drivers/gpu/drm/drm_connector.c                 | 88 +++++++++++++++++++++++++
> > > > >  include/drm/drm_connector.h                     | 36 ++++++++++
> > > > >  6 files changed, 133 insertions(+), 2 deletions(-)
> > > > >
> > > > > diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv
> > > > > index 0f9590834829..caef14c532d4 100644
> > > > > --- a/Documentation/gpu/kms-properties.csv
> > > > > +++ b/Documentation/gpu/kms-properties.csv
> > > > > @@ -15,11 +15,10 @@ Owner Module/Drivers,Group,Property Name,Type,Property Values,Object attached,De
> > > > >  ,,“saturation”,RANGE,"Min=0, Max=100",Connector,TBD
> > > > >  ,,“hue”,RANGE,"Min=0, Max=100",Connector,TBD
> > > > >  ,Virtual GPU,“suggested X”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an X offset for a connector
> > > > >  ,,“suggested Y”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an Y offset for a connector
> > > > >  ,Optional,"""aspect ratio""",ENUM,"{ ""None"", ""4:3"", ""16:9"" }",Connector,TDB
> > > > > -i915,Generic,"""Broadcast RGB""",ENUM,"{ ""Automatic"", ""Full"", ""Limited 16:235"" }",Connector,"When this property is set to Limited 16:235 and CTM is set, the hardware will be programmed with the result of the multiplication of CTM by the limited range matrix to ensure the pixels normally in the range 0..1.0 are remapped to the range 16/255..235/255."
> > > >
> > > > Should it still be defined as a generic property?
> > >
> > > I'm not sure what you mean here, sorry. It's being documented as a
> > > connector property now, so it's very much still listed as a generic
> > > property?
> >
> > I didn't perform my duty well enough and I didn't check the file for
> > other instances of the property. Now I indeed see a generic "Broadcast
> > RGB" property, but to me it looks like having a different set of values:
> >
> > ,,"""Broadcast RGB""",ENUM,"{ “off”, “auto”, “on” }",Connector,TBD
>
> That's not really what I meant: that file is deprecated now and it's not
> where we document the properties anymore. This patch has improved that
> documentation and moved it to the new place, and removed the deprecated
> part.
>
> However, this line shouldn't be there at all. I'll add a patch to remove
> it.

SG

>
> Thanks!
> Maxime
diff mbox series

Patch

diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv
index 0f9590834829..caef14c532d4 100644
--- a/Documentation/gpu/kms-properties.csv
+++ b/Documentation/gpu/kms-properties.csv
@@ -15,11 +15,10 @@  Owner Module/Drivers,Group,Property Name,Type,Property Values,Object attached,De
 ,,“saturation”,RANGE,"Min=0, Max=100",Connector,TBD
 ,,“hue”,RANGE,"Min=0, Max=100",Connector,TBD
 ,Virtual GPU,“suggested X”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an X offset for a connector
 ,,“suggested Y”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an Y offset for a connector
 ,Optional,"""aspect ratio""",ENUM,"{ ""None"", ""4:3"", ""16:9"" }",Connector,TDB
-i915,Generic,"""Broadcast RGB""",ENUM,"{ ""Automatic"", ""Full"", ""Limited 16:235"" }",Connector,"When this property is set to Limited 16:235 and CTM is set, the hardware will be programmed with the result of the multiplication of CTM by the limited range matrix to ensure the pixels normally in the range 0..1.0 are remapped to the range 16/255..235/255."
 ,,“audio”,ENUM,"{ ""force-dvi"", ""off"", ""auto"", ""on"" }",Connector,TBD
 ,SDVO-TV,“mode”,ENUM,"{ ""NTSC_M"", ""NTSC_J"", ""NTSC_443"", ""PAL_B"" } etc.",Connector,TBD
 ,,"""left_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
 ,,"""right_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
 ,,"""top_margin""",RANGE,"Min=0, Max= SDVO dependent",Connector,TBD
diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
index 93cb30dba86e..888fe1fe9594 100644
--- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c
+++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c
@@ -23,10 +23,11 @@  void __drm_atomic_helper_connector_hdmi_reset(struct drm_connector *connector,
 {
 	unsigned int max_bpc = connector->max_bpc;
 
 	new_conn_state->max_bpc = max_bpc;
 	new_conn_state->max_requested_bpc = max_bpc;
+	new_conn_state->hdmi.broadcast_rgb = DRM_HDMI_BROADCAST_RGB_AUTO;
 }
 EXPORT_SYMBOL(__drm_atomic_helper_connector_hdmi_reset);
 
 static const struct drm_display_mode *
 connector_state_get_mode(const struct drm_connector_state *conn_state)
@@ -318,11 +319,12 @@  int drm_atomic_helper_connector_hdmi_check(struct drm_connector *connector,
 
 	ret = hdmi_compute_config(connector, new_conn_state, mode);
 	if (ret)
 		return ret;
 
-	if (old_conn_state->hdmi.output_bpc != new_conn_state->hdmi.output_bpc ||
+	if (old_conn_state->hdmi.broadcast_rgb != new_conn_state->hdmi.broadcast_rgb ||
+	    old_conn_state->hdmi.output_bpc != new_conn_state->hdmi.output_bpc ||
 	    old_conn_state->hdmi.output_format != new_conn_state->hdmi.output_format) {
 		struct drm_crtc *crtc = new_conn_state->crtc;
 		struct drm_crtc_state *crtc_state;
 
 		crtc_state = drm_atomic_get_crtc_state(state, crtc);
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 26f9e525c0a0..3e57d98d8418 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -1143,10 +1143,12 @@  static void drm_atomic_connector_print_state(struct drm_printer *p,
 	drm_printf(p, "\tmax_requested_bpc=%d\n", state->max_requested_bpc);
 	drm_printf(p, "\tcolorspace=%s\n", drm_get_colorspace_name(state->colorspace));
 
 	if (connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
 	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIB) {
+		drm_printf(p, "\tbroadcast_rgb=%s\n",
+			   drm_hdmi_connector_get_broadcast_rgb_name(state->hdmi.broadcast_rgb));
 		drm_printf(p, "\toutput_bpc=%u\n", state->hdmi.output_bpc);
 		drm_printf(p, "\toutput_format=%s\n",
 			   drm_hdmi_connector_get_output_format_name(state->hdmi.output_format));
 		drm_printf(p, "\ttmds_char_rate=%llu\n", state->hdmi.tmds_char_rate);
 	}
diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index fc16fddee5c5..22bbb2d83e30 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -774,10 +774,12 @@  static int drm_atomic_connector_set_property(struct drm_connector *connector,
 						   fence_ptr);
 	} else if (property == connector->max_bpc_property) {
 		state->max_requested_bpc = val;
 	} else if (property == connector->privacy_screen_sw_state_property) {
 		state->privacy_screen_sw_state = val;
+	} else if (property == connector->broadcast_rgb_property) {
+		state->hdmi.broadcast_rgb = val;
 	} else if (connector->funcs->atomic_set_property) {
 		return connector->funcs->atomic_set_property(connector,
 				state, property, val);
 	} else {
 		drm_dbg_atomic(connector->dev,
@@ -857,10 +859,12 @@  drm_atomic_connector_get_property(struct drm_connector *connector,
 		*val = 0;
 	} else if (property == connector->max_bpc_property) {
 		*val = state->max_requested_bpc;
 	} else if (property == connector->privacy_screen_sw_state_property) {
 		*val = state->privacy_screen_sw_state;
+	} else if (property == connector->broadcast_rgb_property) {
+		*val = state->hdmi.broadcast_rgb;
 	} else if (connector->funcs->atomic_get_property) {
 		return connector->funcs->atomic_get_property(connector,
 				state, property, val);
 	} else {
 		drm_dbg_atomic(dev,
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 555eac20e5a4..bdd3361ccc73 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -1210,10 +1210,33 @@  static const u32 dp_colorspaces =
 	BIT(DRM_MODE_COLORIMETRY_SYCC_601) |
 	BIT(DRM_MODE_COLORIMETRY_OPYCC_601) |
 	BIT(DRM_MODE_COLORIMETRY_BT2020_CYCC) |
 	BIT(DRM_MODE_COLORIMETRY_BT2020_YCC);
 
+static const struct drm_prop_enum_list broadcast_rgb_names[] = {
+	{ DRM_HDMI_BROADCAST_RGB_AUTO, "Automatic" },
+	{ DRM_HDMI_BROADCAST_RGB_FULL, "Full" },
+	{ DRM_HDMI_BROADCAST_RGB_LIMITED, "Limited 16:235" },
+};
+
+/*
+ * drm_hdmi_connector_get_broadcast_rgb_name - Return a string for HDMI connector RGB broadcast selection
+ * @broadcast_rgb: Broadcast RGB selection to compute name of
+ *
+ * Returns: the name of the Broadcast RGB selection, or NULL if the type
+ * is not valid.
+ */
+const char *
+drm_hdmi_connector_get_broadcast_rgb_name(enum drm_hdmi_broadcast_rgb broadcast_rgb)
+{
+	if (broadcast_rgb >= ARRAY_SIZE(broadcast_rgb_names))
+		return NULL;
+
+	return broadcast_rgb_names[broadcast_rgb].name;
+}
+EXPORT_SYMBOL(drm_hdmi_connector_get_broadcast_rgb_name);
+
 static const char * const output_format_str[] = {
 	[HDMI_COLORSPACE_RGB]		= "RGB",
 	[HDMI_COLORSPACE_YUV420]	= "YUV 4:2:0",
 	[HDMI_COLORSPACE_YUV422]	= "YUV 4:2:2",
 	[HDMI_COLORSPACE_YUV444]	= "YUV 4:4:4",
@@ -1706,10 +1729,42 @@  void drm_connector_attach_dp_subconnector_property(struct drm_connector *connect
 EXPORT_SYMBOL(drm_connector_attach_dp_subconnector_property);
 
 /**
  * DOC: HDMI connector properties
  *
+ * Broadcast RGB (HDMI specific)
+ *      Indicates the Quantization Range (Full vs Limited) used. The color
+ *      processing pipeline will be adjusted to match the value of the
+ *      property, and the Infoframes will be generated and sent accordingly.
+ *
+ *      This property is only relevant if the HDMI output format is RGB. If
+ *      it's one of the YCbCr variant, it will be ignored.
+ *
+ *      The CRTC attached to the connector must be configured by user-space to
+ *      always produce full-range pixels.
+ *
+ *      The value of this property can be one of the following:
+ *
+ *      Automatic:
+ *              The quantization range is selected automatically based on the
+ *              mode according to the HDMI specifications (HDMI 1.4b - Section
+ *              6.6 - Video Quantization Ranges).
+ *
+ *      Full:
+ *              Full quantization range is forced.
+ *
+ *      Limited 16:235:
+ *              Limited quantization range is forced. Unlike the name suggests,
+ *              this works for any number of bits-per-component.
+ *
+ *      Property values other than Automatic can result in colors being off (if
+ *      limited is selected but the display expects full), or a black screen
+ *      (if full is selected but the display expects limited).
+ *
+ *      Drivers can set up this property by calling
+ *      drm_connector_attach_broadcast_rgb_property().
+ *
  * content type (HDMI specific):
  *	Indicates content type setting to be used in HDMI infoframes to indicate
  *	content type for the external device, so that it adjusts its display
  *	settings accordingly.
  *
@@ -2568,10 +2623,43 @@  int drm_connector_attach_hdr_output_metadata_property(struct drm_connector *conn
 
 	return 0;
 }
 EXPORT_SYMBOL(drm_connector_attach_hdr_output_metadata_property);
 
+/**
+ * drm_connector_attach_broadcast_rgb_property - attach "Broadcast RGB" property
+ * @connector: connector to attach the property on.
+ *
+ * This is used to add support for forcing the RGB range on a connector
+ *
+ * Returns:
+ * Zero on success, negative errno on failure.
+ */
+int drm_connector_attach_broadcast_rgb_property(struct drm_connector *connector)
+{
+	struct drm_device *dev = connector->dev;
+	struct drm_property *prop;
+
+	prop = connector->broadcast_rgb_property;
+	if (!prop) {
+		prop = drm_property_create_enum(dev, DRM_MODE_PROP_ENUM,
+						"Broadcast RGB",
+						broadcast_rgb_names,
+						ARRAY_SIZE(broadcast_rgb_names));
+		if (!prop)
+			return -EINVAL;
+
+		connector->broadcast_rgb_property = prop;
+	}
+
+	drm_object_attach_property(&connector->base, prop,
+				   DRM_HDMI_BROADCAST_RGB_AUTO);
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_connector_attach_broadcast_rgb_property);
+
 /**
  * drm_connector_attach_colorspace_property - attach "Colorspace" property
  * @connector: connector to attach the property on.
  *
  * This is used to allow the userspace to signal the output colorspace
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 3c0b6694074f..a40eaf3a8ce4 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -367,10 +367,33 @@  enum drm_panel_orientation {
 	DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP,
 	DRM_MODE_PANEL_ORIENTATION_LEFT_UP,
 	DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,
 };
 
+/**
+ * enum drm_hdmi_broadcast_rgb - Broadcast RGB Selection for an HDMI @drm_connector
+ */
+enum drm_hdmi_broadcast_rgb {
+	/**
+	 * @DRM_HDMI_BROADCAST_RGB_AUTO: The RGB range is selected
+	 * automatically based on the mode.
+	 */
+	DRM_HDMI_BROADCAST_RGB_AUTO,
+
+	/**
+	 * @DRM_HDMI_BROADCAST_RGB_FULL: Full range RGB is forced.
+	 */
+	DRM_HDMI_BROADCAST_RGB_FULL,
+
+	/**
+	 * @DRM_HDMI_BROADCAST_RGB_LIMITED: Limited range RGB is forced.
+	 */
+	DRM_HDMI_BROADCAST_RGB_LIMITED,
+};
+
+const char *
+drm_hdmi_connector_get_broadcast_rgb_name(enum drm_hdmi_broadcast_rgb broadcast_rgb);
 const char *
 drm_hdmi_connector_get_output_format_name(enum hdmi_colorspace fmt);
 
 /**
  * struct drm_monitor_range_info - Panel's Monitor range in EDID for
@@ -1039,10 +1062,16 @@  struct drm_connector_state {
 	/**
 	 * @hdmi: HDMI-related variable and properties. Filled by
 	 * @drm_atomic_helper_connector_hdmi_check().
 	 */
 	struct {
+		/**
+		 * @broadcast_rgb: Connector property to pass the
+		 * Broadcast RGB selection value.
+		 */
+		enum drm_hdmi_broadcast_rgb broadcast_rgb;
+
 		/**
 		 * @output_bpc: Bits per color channel to output.
 		 */
 		unsigned int output_bpc;
 
@@ -1751,10 +1780,16 @@  struct drm_connector {
 	 * @privacy_screen_hw_state_property: Optional atomic property for the
 	 * connector to report the actual integrated privacy screen state.
 	 */
 	struct drm_property *privacy_screen_hw_state_property;
 
+	/**
+	 * @broadcast_rgb_property: Connector property to set the
+	 * Broadcast RGB selection to output with.
+	 */
+	struct drm_property *broadcast_rgb_property;
+
 #define DRM_CONNECTOR_POLL_HPD (1 << 0)
 #define DRM_CONNECTOR_POLL_CONNECT (1 << 1)
 #define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2)
 
 	/**
@@ -2090,10 +2125,11 @@  int drm_mode_create_scaling_mode_property(struct drm_device *dev);
 int drm_connector_attach_content_type_property(struct drm_connector *dev);
 int drm_connector_attach_scaling_mode_property(struct drm_connector *connector,
 					       u32 scaling_mode_mask);
 int drm_connector_attach_vrr_capable_property(
 		struct drm_connector *connector);
+int drm_connector_attach_broadcast_rgb_property(struct drm_connector *connector);
 int drm_connector_attach_colorspace_property(struct drm_connector *connector);
 int drm_connector_attach_hdr_output_metadata_property(struct drm_connector *connector);
 bool drm_connector_atomic_hdr_metadata_equal(struct drm_connector_state *old_state,
 					     struct drm_connector_state *new_state);
 int drm_mode_create_aspect_ratio_property(struct drm_device *dev);