diff options
| -rw-r--r-- | hw/usb/hcd-uhci.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/hw/usb/hcd-uhci.c b/hw/usb/hcd-uhci.c index ef326330d3..078be2ad6a 100644 --- a/hw/usb/hcd-uhci.c +++ b/hw/usb/hcd-uhci.c @@ -556,6 +556,10 @@ static void uhci_ioport_writew(void *opaque, uint32_t addr, uint32_t val) } } port->ctrl &= UHCI_PORT_READ_ONLY; + /* enabled may only be set if a device is connected */ + if (!(port->ctrl & UHCI_PORT_CCS)) { + val &= ~UHCI_PORT_EN; + } port->ctrl |= (val & ~UHCI_PORT_READ_ONLY); /* some bits are reset when a '1' is written to them */ port->ctrl &= ~(val & UHCI_PORT_WRITE_CLEAR); |