thunderbolt: Configure port for XDomain

When the port is connected to another host it should be marked as such
in the USB4 port capability. This information is used by the router
during sleep and wakeup.

Also do the same for legacy switches via link controller vendor specific
registers.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

1 files changed, 54 insertions, 0 deletions

diff --git a/drivers/thunderbolt/lc.c b/drivers/thunderbolt/lc.c
index 5c209a570360..44647fa1ec1c 100644
--- a/drivers/thunderbolt/lc.c
+++ b/drivers/thunderbolt/lc.c
@@ -104,6 +104,60 @@ void tb_lc_unconfigure_port(struct tb_port *port)
 	tb_lc_set_port_configured(port, false);
 }
 
+static int tb_lc_set_xdomain_configured(struct tb_port *port, bool configure)
+{
+	struct tb_switch *sw = port->sw;
+	u32 ctrl, lane;
+	int cap, ret;
+
+	if (sw->generation < 2)
+		return 0;
+
+	cap = find_port_lc_cap(port);
+	if (cap < 0)
+		return cap;
+
+	ret = tb_sw_read(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
+	if (ret)
+		return ret;
+
+	/* Resolve correct lane */
+	if (port->port % 2)
+		lane = TB_LC_SX_CTRL_L1D;
+	else
+		lane = TB_LC_SX_CTRL_L2D;
+
+	if (configure)
+		ctrl |= lane;
+	else
+		ctrl &= ~lane;
+
+	return tb_sw_write(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
+}
+
+/**
+ * tb_lc_configure_xdomain() - Inform LC that the link is XDomain
+ * @port: Switch downstream port connected to another host
+ *
+ * Sets the lane configured for XDomain accordingly so that the LC knows
+ * about this. Returns %0 in success and negative errno in failure.
+ */
+int tb_lc_configure_xdomain(struct tb_port *port)
+{
+	return tb_lc_set_xdomain_configured(port, true);
+}
+
+/**
+ * tb_lc_unconfigure_xdomain() - Unconfigure XDomain from port
+ * @port: Switch downstream port that was connected to another host
+ *
+ * Unsets the lane XDomain configuration.
+ */
+void tb_lc_unconfigure_xdomain(struct tb_port *port)
+{
+	tb_lc_set_xdomain_configured(port, false);
+}
+
 /**
  * tb_lc_set_sleep() - Inform LC that the switch is going to sleep
  * @sw: Switch to set sleep