usbcore: Refine USB3.0 device suspend and resume

In the past, we use USB2.0 request to suspend and resume a USB3.0 device.
Actually, USB3.0 hub does not support Set/Clear PORT_SUSPEND request,
instead, it uses Set PORT_LINK_STATE request. This patch makes USB3.0 device
suspend/resume comply with USB3.0 specification.

This patch fixes the issue that USB3.0 device can not be suspended when
connected to a USB3.0 external hub.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

1 files changed, 20 insertions, 13 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index dcd78c15f8cd..93035d862c63 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2307,14 +2307,10 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
         }
 
         /* see 7.1.7.6 */
-        /* Clear PORT_POWER if it's a USB3.0 device connected to USB 3.0
-         * external hub.
-         * FIXME: this is a temporary workaround to make the system able
-         * to suspend/resume.
-         */
-        if ((hub->hdev->parent != NULL) && hub_is_superspeed(hub->hdev))
-                status = clear_port_feature(hub->hdev, port1,
-                                                USB_PORT_FEAT_POWER);
+        if (hub_is_superspeed(hub->hdev))
+                status = set_port_feature(hub->hdev,
+                                port1 | (USB_SS_PORT_LS_U3 << 3),
+                                USB_PORT_FEAT_LINK_STATE);
         else
                 status = set_port_feature(hub->hdev, port1,
                                                 USB_PORT_FEAT_SUSPEND);
@@ -2469,8 +2465,13 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
         set_bit(port1, hub->busy_bits);
 
         /* see 7.1.7.7; affects power usage, but not budgeting */
-        status = clear_port_feature(hub->hdev,
-                        port1, USB_PORT_FEAT_SUSPEND);
+        if (hub_is_superspeed(hub->hdev))
+                status = set_port_feature(hub->hdev,
+                                port1 | (USB_SS_PORT_LS_U0 << 3),
+                                USB_PORT_FEAT_LINK_STATE);
+        else
+                status = clear_port_feature(hub->hdev,
+                                port1, USB_PORT_FEAT_SUSPEND);
         if (status) {
                 dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
                                 port1, status);
@@ -2492,9 +2493,15 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
 
  SuspendCleared:
         if (status == 0) {
-                if (portchange & USB_PORT_STAT_C_SUSPEND)
-                        clear_port_feature(hub->hdev, port1,
-                                        USB_PORT_FEAT_C_SUSPEND);
+                if (hub_is_superspeed(hub->hdev)) {
+                        if (portchange & USB_PORT_STAT_C_LINK_STATE)
+                                clear_port_feature(hub->hdev, port1,
+                                        USB_PORT_FEAT_C_PORT_LINK_STATE);
+                } else {
+                        if (portchange & USB_PORT_STAT_C_SUSPEND)
+                                clear_port_feature(hub->hdev, port1,
+                                                USB_PORT_FEAT_C_SUSPEND);
+                }
         }
 
         clear_bit(port1, hub->busy_bits);