[PATCH RESEND v2 25/32] drm/vkms: Introduce configfs for connector supported colorspace

Louis Chauvet posted 32 patches 3 months, 1 week ago
There is a newer version of this series
[PATCH RESEND v2 25/32] drm/vkms: Introduce configfs for connector supported colorspace
Posted by Louis Chauvet 3 months, 1 week ago
Add the attribute supported_colorspaces to configure the supported
colorspace of a connector. It will allows emulating some HDR features of
displays. This feature is only supported for HDMI, DP and eDP connectors.

Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
---
 Documentation/gpu/vkms.rst           |  7 ++++++-
 drivers/gpu/drm/vkms/vkms_configfs.c | 39 ++++++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
index 99c5cf3dbd78..c762cadac6f4 100644
--- a/Documentation/gpu/vkms.rst
+++ b/Documentation/gpu/vkms.rst
@@ -138,11 +138,16 @@ Last but not least, create one or more connectors::
 
   sudo mkdir /config/vkms/my-vkms/connectors/connector0
 
-Connectors have 2 configurable attribute:
+Connectors have 3 configurable attribute:
 
 - status: Connection status: 1 connected, 2 disconnected, 3 unknown (same values
   as those exposed by the "status" property of a connector)
 - type: Type of connector. Same values as exposed by the "type" field in drm_connector.
+- supported_colorspaces: Supported colorspaces values for HDMI, DP and eDP connectors.
+  If supported_colorspaces is not 0, the HDR_OUTPUT_METADATA will also be created.
+  Value is a bitfield, 0x1 = NO_DATA, 0x2 = SMPTE_170M_YCC... see enum drm_colorspace
+  for full list.
+
 
 To finish the configuration, link the different pipeline items::
 
diff --git a/drivers/gpu/drm/vkms/vkms_configfs.c b/drivers/gpu/drm/vkms/vkms_configfs.c
index b03e9af569b6..a7f4589403ce 100644
--- a/drivers/gpu/drm/vkms/vkms_configfs.c
+++ b/drivers/gpu/drm/vkms/vkms_configfs.c
@@ -1223,12 +1223,51 @@ static ssize_t connector_type_store(struct config_item *item,
 	return count;
 }
 
+static ssize_t connector_supported_colorspaces_show(struct config_item *item, char *page)
+{
+	struct vkms_configfs_connector *connector;
+	int type;
+
+	connector = connector_item_to_vkms_configfs_connector(item);
+
+	scoped_guard(mutex, &connector->dev->lock)
+		type = vkms_config_connector_get_supported_colorspaces(connector->config);
+
+	return sprintf(page, "%u", type);
+}
+
+static ssize_t connector_supported_colorspaces_store(struct config_item *item,
+						     const char *page, size_t count)
+{
+	struct vkms_configfs_connector *connector;
+	int val, ret;
+
+	connector = connector_item_to_vkms_configfs_connector(item);
+
+	ret = kstrtouint(page, 10, &val);
+	if (ret)
+		return ret;
+
+	if ((val & -BIT(DRM_MODE_COLORIMETRY_COUNT)) != 0)
+		return -EINVAL;
+
+	scoped_guard(mutex, &connector->dev->lock) {
+		if (connector->dev->enabled)
+			return -EBUSY;
+		vkms_config_connector_set_supported_colorspaces(connector->config, val);
+	}
+
+	return count;
+}
+
 CONFIGFS_ATTR(connector_, status);
 CONFIGFS_ATTR(connector_, type);
+CONFIGFS_ATTR(connector_, supported_colorspaces);
 
 static struct configfs_attribute *connector_item_attrs[] = {
 	&connector_attr_status,
 	&connector_attr_type,
+	&connector_attr_supported_colorspaces,
 	NULL,
 };
 

-- 
2.51.0
Re: [PATCH RESEND v2 25/32] drm/vkms: Introduce configfs for connector supported colorspace
Posted by Luca Ceresoli 1 month, 3 weeks ago
On Wed Oct 29, 2025 at 3:37 PM CET, Louis Chauvet wrote:
> Add the attribute supported_colorspaces to configure the supported
> colorspace of a connector. It will allows emulating some HDR features of
> displays. This feature is only supported for HDMI, DP and eDP connectors.
>
> Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
> --- a/drivers/gpu/drm/vkms/vkms_configfs.c
> +++ b/drivers/gpu/drm/vkms/vkms_configfs.c
> @@ -1223,12 +1223,51 @@ static ssize_t connector_type_store(struct config_item *item,
>  	return count;
>  }
>
> +static ssize_t connector_supported_colorspaces_show(struct config_item *item, char *page)
> +{
> +	struct vkms_configfs_connector *connector;
> +	int type;

This variable name is not really intuitive. 'colorspaces' maybe?

With that change:

 Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com