[PATCH v5 9/9] drm/bridge: it6505: Add typec_mux_set callback function

[Prashant Malani <pmalani@xxxxxxxxxxxx>]

From: Pin-Yen Lin <treapking@xxxxxxxxxxxx>

Add the callback function when the driver receives state changes of the
Type-C ports. The callback function configures the lane_swap state and
ends up updating the lane swap registers of it6505 bridge chip.

Signed-off-by: Pin-Yen Lin <treapking@xxxxxxxxxxxx>
Signed-off-by: Prashant Malani <pmalani@xxxxxxxxxxxx>
---

v5 is the first version for this patch.

 drivers/gpu/drm/bridge/ite-it6505.c | 58 +++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index cb1dd4cbd33b..87b9bd742b52 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -17,6 +17,7 @@
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/types.h>
+#include <linux/usb/typec_dp.h>
 #include <linux/usb/typec_mux.h>
 #include <linux/wait.h>
 
@@ -404,6 +405,7 @@ struct debugfs_entries {
 };
 
 struct it6505_port_data {
+	bool dp_connected;
 	struct typec_mux_dev *typec_mux;
 	struct it6505 *it6505;
 };
@@ -3237,9 +3239,65 @@ static void it6505_shutdown(struct i2c_client *client)
 		it6505_lane_off(it6505);
 }
 
+static void it6505_typec_ports_update(struct it6505 *it6505)
+{
+	usleep_range(3000, 4000);
+
+	if (it6505->typec_ports[0].dp_connected && it6505->typec_ports[1].dp_connected)
+		/* Both ports available, do nothing to retain the current one. */
+		return;
+	else if (it6505->typec_ports[0].dp_connected)
+		it6505->lane_swap = false;
+	else if (it6505->typec_ports[1].dp_connected)
+		it6505->lane_swap = true;
+
+	usleep_range(3000, 4000);
+}
+
 static int it6505_typec_mux_set(struct typec_mux_dev *mux,
 				struct typec_mux_state *state)
 {
+	struct it6505_port_data *data = typec_mux_get_drvdata(mux);
+	struct it6505 *it6505 = data->it6505;
+	struct device *dev = &it6505->client->dev;
+	bool old_dp_connected, new_dp_connected;
+
+	if (it6505->num_typec_switches == 1)
+		return 0;
+
+	mutex_lock(&it6505->extcon_lock);
+
+	old_dp_connected = it6505->typec_ports[0].dp_connected ||
+			   it6505->typec_ports[1].dp_connected;
+
+	dev_dbg(dev, "mux_set dp_connected: c0=%d, c1=%d\n",
+		it6505->typec_ports[0].dp_connected, it6505->typec_ports[1].dp_connected);
+
+	data->dp_connected = (state->alt && state->alt->svid == USB_TYPEC_DP_SID &&
+			      state->alt->mode == USB_TYPEC_DP_MODE);
+
+	new_dp_connected = it6505->typec_ports[0].dp_connected ||
+			   it6505->typec_ports[1].dp_connected;
+
+	if (it6505->enable_drv_hold) {
+		dev_dbg(dev, "enable driver hold");
+		goto unlock;
+	}
+
+	it6505_typec_ports_update(it6505);
+
+	if (!old_dp_connected && new_dp_connected)
+		pm_runtime_get_sync(dev);
+
+	if (old_dp_connected && !new_dp_connected) {
+		pm_runtime_put_sync(dev);
+		if (it6505->bridge.dev)
+			drm_helper_hpd_irq_event(it6505->bridge.dev);
+		memset(it6505->dpcd, 0, sizeof(it6505->dpcd));
+	}
+
+unlock:
+	mutex_unlock(&it6505->extcon_lock);
 	return 0;
 }
 
-- 
2.37.0.rc0.104.g0611611a94-goog