[PATCH v2 2/2] usb-redir: remove 'remote wakeup' flag from configuration descriptor

[Yuri Benditovich]

If the redirected device has this capability, Windows guest may
place the device into D2 and expect it to wake when the device
becomes active, but this will never happen. For example, when
internal Bluetooth adapter is redirected, keyboards and mice
connected to it do not work. Current commit removes this
capability (starting from machine 4.2)
Set 'usb-redir.suppress-remote-wake' property to 'off' to keep
'remote wake' as is or to 'on' to remove 'remote wake' on
4.1 or earlier.

Signed-off-by: Yuri Benditovich <address@hidden>
---
 hw/core/machine.c |  1 +
 hw/usb/redirect.c | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/hw/core/machine.c b/hw/core/machine.c
index 8c0eaad091..44408ff87c 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -30,6 +30,7 @@
 GlobalProperty hw_compat_4_1[] = {
     { "virtio-pci", "x-pcie-flr-init", "off" },
     { "usb-host", "suppress-remote-wake", "off" },
+    { "usb-redir", "suppress-remote-wake", "off" },
 };
 const size_t hw_compat_4_1_len = G_N_ELEMENTS(hw_compat_4_1);
 
diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c
index e0f5ca6f81..b5c1558687 100644
--- a/hw/usb/redirect.c
+++ b/hw/usb/redirect.c
@@ -113,6 +113,7 @@ struct USBRedirDevice {
     /* Properties */
     CharBackend cs;
     bool enable_streams;
+    bool suppress_remote_wake;
     uint8_t debug;
     int32_t bootindex;
     char *filter_str;
@@ -1989,6 +1990,23 @@ static void usbredir_control_packet(void *priv, uint64_t 
id,
             memcpy(dev->dev.data_buf, data, data_len);
         }
         p->actual_length = len;
+        /*
+         * If this is GET_DESCRIPTOR request for configuration descriptor,
+         * remove 'remote wakeup' flag from it to prevent idle power down
+         * in Windows guest
+         */
+        if (dev->suppress_remote_wake &&
+            control_packet->requesttype == USB_DIR_IN &&
+            control_packet->request == USB_REQ_GET_DESCRIPTOR &&
+            control_packet->value == (USB_DT_CONFIG << 8) &&
+            control_packet->index == 0 &&
+            /* bmAttributes field of config descriptor */
+            len > 7 && (dev->dev.data_buf[7] & USB_CFG_ATT_WAKEUP)) {
+                DPRINTF("Removed remote wake %04X:%04X\n",
+                    dev->device_info.vendor_id,
+                    dev->device_info.product_id);
+                dev->dev.data_buf[7] &= ~USB_CFG_ATT_WAKEUP;
+            }
         usb_generic_async_ctrl_complete(&dev->dev, p);
     }
     free(data);
@@ -2530,6 +2548,8 @@ static Property usbredir_properties[] = {
     DEFINE_PROP_UINT8("debug", USBRedirDevice, debug, usbredirparser_warning),
     DEFINE_PROP_STRING("filter", USBRedirDevice, filter_str),
     DEFINE_PROP_BOOL("streams", USBRedirDevice, enable_streams, true),
+    DEFINE_PROP_BOOL("suppress-remote-wake", USBRedirDevice,
+                     suppress_remote_wake, true),
     DEFINE_PROP_END_OF_LIST(),
 };
 
-- 
2.17.1