drm: report dp downstream port type as a subconnector property

Currently, downstream port type is only reported in debugfs. This
information should be considered important since it reflects the actual
physical connector type. Some userspace (e.g. window compositors)
may want to show this info to a user.

The 'subconnector' property is already utilized for DVI-I and TV-out for
reporting connector subtype.

The initial motivation for this feature came from i2c test [1].
It is supposed to be skipped on VGA connectors, but it cannot
detect VGA over DP and fails instead.

v2:
 - Ville: utilized drm_dp_is_branch()
 - Ville: implement DP 1.0 downstream type info
 - Replaced create_dp_properties with add_dp_subconnector_property
 - Added dp_set_subconnector_property helper

v4:
 - Ville: add DP1.0 best assumption about subconnector
 - Ville: assume DVI is DVI-D
 - Ville: reuse Writeback enum value for Virtual subconnector
 - Renamed #defines: HDMI -> HDMIA, DP -> DisplayPort

v5: rebase

v6:
 - Jani Nikula: renamed a function name
 - Jani Nikula: addressed the issues with documentation

[1]: https://bugs.freedesktop.org/show_bug.cgi?id=104097

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Signed-off-by: Jeevan B <jeevan.b@intel.com>
Signed-off-by: Oleg Vasilev <oleg.vasilev@intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1587732655-17544-1-git-send-email-jeevan.b@intel.com
This commit is contained in:
Oleg Vasilev
2020-04-24 18:20:51 +05:30
committed by Maarten Lankhorst
parent a343160235
commit e5b9277328
6 changed files with 148 additions and 10 deletions

View File

@@ -597,6 +597,77 @@ void drm_dp_downstream_debug(struct seq_file *m,
}
EXPORT_SYMBOL(drm_dp_downstream_debug);
/**
* drm_dp_subconnector_type() - get DP branch device type
*
*/
enum drm_mode_subconnector
drm_dp_subconnector_type(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
const u8 port_cap[4])
{
int type;
if (!drm_dp_is_branch(dpcd))
return DRM_MODE_SUBCONNECTOR_Native;
/* DP 1.0 approach */
if (dpcd[DP_DPCD_REV] == DP_DPCD_REV_10) {
type = dpcd[DP_DOWNSTREAMPORT_PRESENT] &
DP_DWN_STRM_PORT_TYPE_MASK;
switch (type) {
case DP_DWN_STRM_PORT_TYPE_TMDS:
/* Can be HDMI or DVI-D, DVI-D is a safer option */
return DRM_MODE_SUBCONNECTOR_DVID;
case DP_DWN_STRM_PORT_TYPE_ANALOG:
/* Can be VGA or DVI-A, VGA is more popular */
return DRM_MODE_SUBCONNECTOR_VGA;
case DP_DWN_STRM_PORT_TYPE_DP:
return DRM_MODE_SUBCONNECTOR_DisplayPort;
case DP_DWN_STRM_PORT_TYPE_OTHER:
default:
return DRM_MODE_SUBCONNECTOR_Unknown;
}
}
type = port_cap[0] & DP_DS_PORT_TYPE_MASK;
switch (type) {
case DP_DS_PORT_TYPE_DP:
case DP_DS_PORT_TYPE_DP_DUALMODE:
return DRM_MODE_SUBCONNECTOR_DisplayPort;
case DP_DS_PORT_TYPE_VGA:
return DRM_MODE_SUBCONNECTOR_VGA;
case DP_DS_PORT_TYPE_DVI:
return DRM_MODE_SUBCONNECTOR_DVID;
case DP_DS_PORT_TYPE_HDMI:
return DRM_MODE_SUBCONNECTOR_HDMIA;
case DP_DS_PORT_TYPE_WIRELESS:
return DRM_MODE_SUBCONNECTOR_Wireless;
case DP_DS_PORT_TYPE_NON_EDID:
default:
return DRM_MODE_SUBCONNECTOR_Unknown;
}
}
EXPORT_SYMBOL(drm_dp_subconnector_type);
/**
* drm_mode_set_dp_subconnector_property - set subconnector for DP connector
*
* Called by a driver on every detect event.
*/
void drm_dp_set_subconnector_property(struct drm_connector *connector,
enum drm_connector_status status,
const u8 *dpcd,
const u8 port_cap[4])
{
enum drm_mode_subconnector subconnector = DRM_MODE_SUBCONNECTOR_Unknown;
if (status == connector_status_connected)
subconnector = drm_dp_subconnector_type(dpcd, port_cap);
drm_object_property_set_value(&connector->base,
connector->dev->mode_config.dp_subconnector_property,
subconnector);
}
EXPORT_SYMBOL(drm_dp_set_subconnector_property);
/*
* I2C-over-AUX implementation
*/