thunderbolt: Enable wakes from system suspend

In order for the router and the whole domain to wake up from system
suspend states we need to enable wakes for the connected routers. For
device routers we enable wakes from PCIe and USB 3.x. This allows
devices such as keyboards connected to USB 3.x hub that is tunneled to
wake the system up as expected. For all routers we enabled wake on USB4
for each connected ports. This is used to propagate the wake from router
to another.

Do the same for legacy routers through link controller vendor specific
registers as documented in USB4 spec chapter 13.

While there correct kernel-doc of usb4_switch_set_sleep() -- it does not
enable wakes instead there is a separate function (usb4_switch_set_wake())
that does.

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

1 files changed, 110 insertions, 2 deletions

diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 59b8b51d1fa4..40f13579a3fe 100644
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -196,6 +196,46 @@ static int usb4_switch_op(struct tb_switch *sw, u16 opcode, u8 *status)
 	return 0;
 }
 
+static void usb4_switch_check_wakes(struct tb_switch *sw)
+{
+	struct tb_port *port;
+	bool wakeup = false;
+	u32 val;
+
+	if (!device_may_wakeup(&sw->dev))
+		return;
+
+	if (tb_route(sw)) {
+		if (tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_6, 1))
+			return;
+
+		tb_sw_dbg(sw, "PCIe wake: %s, USB3 wake: %s\n",
+			  (val & ROUTER_CS_6_WOPS) ? "yes" : "no",
+			  (val & ROUTER_CS_6_WOUS) ? "yes" : "no");
+
+		wakeup = val & (ROUTER_CS_6_WOPS | ROUTER_CS_6_WOUS);
+	}
+
+	/* Check for any connected downstream ports for USB4 wake */
+	tb_switch_for_each_port(sw, port) {
+		if (!tb_port_has_remote(port))
+			continue;
+
+		if (tb_port_read(port, &val, TB_CFG_PORT,
+				 port->cap_usb4 + PORT_CS_18, 1))
+			break;
+
+		tb_port_dbg(port, "USB4 wake: %s\n",
+			    (val & PORT_CS_18_WOU4S) ? "yes" : "no");
+
+		if (val & PORT_CS_18_WOU4S)
+			wakeup = true;
+	}
+
+	if (wakeup)
+		pm_wakeup_event(&sw->dev, 0);
+}
+
 static bool link_is_usb4(struct tb_port *port)
 {
 	u32 val;
@@ -229,6 +269,8 @@ int usb4_switch_setup(struct tb_switch *sw)
 	u32 val = 0;
 	int ret;
 
+	usb4_switch_check_wakes(sw);
+
 	if (!tb_route(sw))
 		return 0;
 
@@ -360,11 +402,77 @@ bool usb4_switch_lane_bonding_possible(struct tb_switch *sw)
 }
 
 /**
+ * usb4_switch_set_wake() - Enabled/disable wake
+ * @sw: USB4 router
+ * @flags: Wakeup flags (%0 to disable)
+ *
+ * Enables/disables router to wake up from sleep.
+ */
+int usb4_switch_set_wake(struct tb_switch *sw, unsigned int flags)
+{
+	struct tb_port *port;
+	u64 route = tb_route(sw);
+	u32 val;
+	int ret;
+
+	/*
+	 * Enable wakes coming from all USB4 downstream ports (from
+	 * child routers). For device routers do this also for the
+	 * upstream USB4 port.
+	 */
+	tb_switch_for_each_port(sw, port) {
+		if (!route && tb_is_upstream_port(port))
+			continue;
+
+		ret = tb_port_read(port, &val, TB_CFG_PORT,
+				   port->cap_usb4 + PORT_CS_19, 1);
+		if (ret)
+			return ret;
+
+		val &= ~(PORT_CS_19_WOC | PORT_CS_19_WOD | PORT_CS_19_WOU4);
+
+		if (flags & TB_WAKE_ON_CONNECT)
+			val |= PORT_CS_19_WOC;
+		if (flags & TB_WAKE_ON_DISCONNECT)
+			val |= PORT_CS_19_WOD;
+		if (flags & TB_WAKE_ON_USB4)
+			val |= PORT_CS_19_WOU4;
+
+		ret = tb_port_write(port, &val, TB_CFG_PORT,
+				    port->cap_usb4 + PORT_CS_19, 1);
+		if (ret)
+			return ret;
+	}
+
+	/*
+	 * Enable wakes from PCIe and USB 3.x on this router. Only
+	 * needed for device routers.
+	 */
+	if (route) {
+		ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
+		if (ret)
+			return ret;
+
+		val &= ~(ROUTER_CS_5_WOP | ROUTER_CS_5_WOU);
+		if (flags & TB_WAKE_ON_USB3)
+			val |= ROUTER_CS_5_WOU;
+		if (flags & TB_WAKE_ON_PCIE)
+			val |= ROUTER_CS_5_WOP;
+
+		ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
  * usb4_switch_set_sleep() - Prepare the router to enter sleep
  * @sw: USB4 router
  *
- * Enables wakes and sets sleep bit for the router. Returns when the
- * router sleep ready bit has been asserted.
+ * Sets sleep bit for the router. Returns when the router sleep ready
+ * bit has been asserted.
  */
 int usb4_switch_set_sleep(struct tb_switch *sw)
 {