From: Chaoyi Chen <chaoyi.chen@xxxxxxxxxxxxxx>
The RK3399 has two USB/DP combo PHY and one CDN-DP controller. And
the CDN-DP can be switched to output to one of the PHYs. If both ports
are plugged into DP, DP will select the first port for output.
This patch adds support for multiple bridges, enabling users to flexibly
select the output port. For each PHY port, a separate encoder and bridge
are registered.
The change is based on the DRM AUX HPD bridge, rather than the
extcon approach. This requires the DT to correctly describe the
connections between the PHY, USB connector, and DP controller.
And cdn_dp_parse_hpd_bridge_dt() will parses it and determines
whether to register one or two bridges.
Since there is only one DP controller, only one of the PHY ports can
output at a time. The key is how to switch between different PHYs,
which is handled by cdn_dp_switch_port() and cdn_dp_enable().
There are two cases:
1. Neither bridge is enabled. In this case, both bridges can
independently read the EDID, and the PHY port may switch before
reading the EDID.
2. One bridge is already enabled. In this case, other bridges are not
allowed to read the EDID.
Since the scenario of two ports plug in at the same time is rare,
I don't have a board which support two TypeC connector to test this.
Therefore, I tested forced switching on a single PHY port, as well as
output using a fake PHY port alongside a real PHY port.
Signed-off-by: Chaoyi Chen <chaoyi.chen@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/rockchip/Kconfig | 1 +
drivers/gpu/drm/rockchip/cdn-dp-core.c | 398 +++++++++++++++++++++----
drivers/gpu/drm/rockchip/cdn-dp-core.h | 23 +-
3 files changed, 366 insertions(+), 56 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/Kconfig b/drivers/gpu/drm/rockchip/Kconfig
index faf50d872be3..3a6266279323 100644
--- a/drivers/gpu/drm/rockchip/Kconfig
+++ b/drivers/gpu/drm/rockchip/Kconfig
@@ -55,6 +55,7 @@ config ROCKCHIP_CDN_DP
select DRM_DISPLAY_HELPER
select DRM_BRIDGE_CONNECTOR
select DRM_DISPLAY_DP_HELPER
+ select DRM_AUX_HPD_BRIDGE
help
This selects support for Rockchip SoC specific extensions
for the cdn DP driver. If you want to enable Dp on
diff --git a/drivers/gpu/drm/rockchip/cdn-dp-core.c b/drivers/gpu/drm/rockchip/cdn-dp-core.c
index 1e27301584a4..784f5656fcc4 100644
--- a/drivers/gpu/drm/rockchip/cdn-dp-core.c
+++ b/drivers/gpu/drm/rockchip/cdn-dp-core.c
@@ -27,16 +27,17 @@
#include "cdn-dp-core.h"
#include "cdn-dp-reg.h"
-static inline struct cdn_dp_device *bridge_to_dp(struct drm_bridge *bridge)
+static int cdn_dp_switch_port(struct cdn_dp_device *dp, struct cdn_dp_port *prev_port,
+ struct cdn_dp_port *port);
+
+static inline struct cdn_dp_bridge *bridge_to_dp_bridge(struct drm_bridge *bridge)
{
- return container_of(bridge, struct cdn_dp_device, bridge);
+ return container_of(bridge, struct cdn_dp_bridge, bridge);
}
-static inline struct cdn_dp_device *encoder_to_dp(struct drm_encoder *encoder)
+static inline struct cdn_dp_device *bridge_to_dp(struct drm_bridge *bridge)
{
- struct rockchip_encoder *rkencoder = to_rockchip_encoder(encoder);
-
- return container_of(rkencoder, struct cdn_dp_device, encoder);
+ return bridge_to_dp_bridge(bridge)->parent;
}
#define GRF_SOC_CON9 0x6224
@@ -191,14 +192,27 @@ static int cdn_dp_get_sink_count(struct cdn_dp_device *dp, u8 *sink_count)
static struct cdn_dp_port *cdn_dp_connected_port(struct cdn_dp_device *dp)
{
struct cdn_dp_port *port;
- int i, lanes;
+ int i, lanes[MAX_PHY];
for (i = 0; i < dp->ports; i++) {
port = dp->port[i];
- lanes = cdn_dp_get_port_lanes(port);
- if (lanes)
+ lanes[i] = cdn_dp_get_port_lanes(port);
+ if (!dp->hpd_bridge_valid)
return port;
}
+
+ if (dp->hpd_bridge_valid) {
+ /* If more than one port is available, pick the last active port */
+ if (dp->active_port > 0 && lanes[dp->active_port])
+ return dp->port[dp->active_port];
+
+ /* If the last active port is not available, pick an available port in order */
+ for (i = 0; i < dp->bridge_count; i++) {
+ if (lanes[i])
+ return dp->port[i];
+ }
+ }
+
return NULL;
}
@@ -239,10 +253,11 @@ static enum drm_connector_status
cdn_dp_bridge_detect(struct drm_bridge *bridge, struct drm_connector *connector)
{
struct cdn_dp_device *dp = bridge_to_dp(bridge);
+ struct cdn_dp_bridge *dp_bridge = bridge_to_dp_bridge(bridge);
enum drm_connector_status status = connector_status_disconnected;
mutex_lock(&dp->lock);
- if (dp->connected)
+ if (dp_bridge->connected && dp->connected)
status = connector_status_connected;
mutex_unlock(&dp->lock);
@@ -253,10 +268,36 @@ static const struct drm_edid *
cdn_dp_bridge_edid_read(struct drm_bridge *bridge, struct drm_connector *connector)
{
struct cdn_dp_device *dp = bridge_to_dp(bridge);
- const struct drm_edid *drm_edid;
+ struct cdn_dp_bridge *dp_bridge = bridge_to_dp_bridge(bridge);
+ struct cdn_dp_port *port = dp->port[dp_bridge->id];
+ struct cdn_dp_port *prev_port;
+ const struct drm_edid *drm_edid = NULL;
+ int i, ret;
mutex_lock(&dp->lock);
+
+ /* More than one port is available */
+ if (dp->bridge_count > 1 && !port->phy_enabled) {
+ for (i = 0; i < dp->bridge_count; i++) {
+ /* Another port already enable */
+ if (dp->bridge_list[i] != dp_bridge && dp->bridge_list[i]->enabled)
+ goto unlock;
+ /* Find already enabled port */
+ if (dp->port[i]->phy_enabled)
+ prev_port = dp->port[i];
+ }
+
+ /* Switch to current port */
+ if (prev_port) {
+ ret = cdn_dp_switch_port(dp, prev_port, port);
+ if (ret)
+ goto unlock;
+ }
+ }
+
drm_edid = drm_edid_read_custom(connector, cdn_dp_get_edid_block, dp);
