The DisplayPort controller's hot-plug mechanism is based on pinmuxing a
physical signal on a GPIO pin into the controller. This is not always
possible, either because there aren't dedicated GPIOs available or
because the hot-plug signal is a virtual notification, in cases such as
USB Type-C.
For these cases, by implementing the hpd_notify() callback for the
DisplayPort controller's drm_bridge, a downstream drm_bridge
(next_bridge) can be used to track and signal the connection status
changes.
This makes it possible to use downstream drm_bridges such as
display-connector or any virtual mechanism, as long as they are
implemented as a drm_bridge.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[bjorn: Drop connector->fwnode assignment and dev from struct msm_dp]
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/514410/
Link: https://lore.kernel.org/r/20221207220012.16529-10-quic_bjorande@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
The DisplayPort controller's internal HPD interrupt handling is used for
cases where the HPD signal is connected to a GPIO which is pinmuxed into
the DisplayPort controller. In other configurations the HPD notification
might be delivered by the DRM framework from an associated bridge.
This difference is not appropriately represented by the "is_edp"
boolean, but is properly represented by the frameworks invocation of the
hpd_enable() and hpd_disable() callbacks. Switch the current condition
to rely on these callbacks instead.
This ensures appropriate handling of the three cases; no bridge
connected, a bridge without DRM_BRIDGE_OP_HPD and a bridge with
DRM_BRIDGE_OP_HPD.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/514414/
Link: https://lore.kernel.org/r/20221207220012.16529-9-quic_bjorande@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
