[Qemu-devel] [PATCH] fix usb-hid SET_IDLE behaviour

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

Hi all,
the usb-hid spec states that the SET_IDLE request has a 16bit value,
where the upper byte specifies the idle rate (currently unimplemented,
we handle only the 0 case, meaning infinite duration) and the lower
byte specifies the report id (0 means all reports).
In our code we do idle = value, while it should be idle = "upper byte",
especially if the guest issues a GET_IDLE, we should return only the
idle rate while we are returning only the report id.
In practice it doesn't make much difference because I have only seen
SET_VALUE with both bytes set to 0 so far, but still it is wrong.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

---

diff --git a/hw/usb-hid.c b/hw/usb-hid.c
index 972543f..76fdce6 100644
--- a/hw/usb-hid.c
+++ b/hw/usb-hid.c
@@ -65,7 +65,7 @@ typedef struct USBHIDState {
     };
     int kind;
     int protocol;
-    int idle;
+    uint8_t idle;
     int changed;
     void *datain_opaque;
     void (*datain)(void *);
@@ -794,7 +794,7 @@ static int usb_hid_handle_control(USBDevice *dev, int request, int value,
         data[0] = s->idle;
         break;
     case SET_IDLE:
-        s->idle = value;
+        s->idle = (uint8_t) (value >> 8);
         ret = 0;
         break;
     default: