diff options
Diffstat (limited to 'sys/dev/usb/controller/ehci.c')
| -rw-r--r-- | sys/dev/usb/controller/ehci.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/sys/dev/usb/controller/ehci.c b/sys/dev/usb/controller/ehci.c index 9a5cace..cccd76a 100644 --- a/sys/dev/usb/controller/ehci.c +++ b/sys/dev/usb/controller/ehci.c @@ -2189,12 +2189,21 @@ static void ehci_device_bulk_start(struct usb2_xfer *xfer) { ehci_softc_t *sc = EHCI_BUS2SC(xfer->xroot->bus); + uint32_t temp; /* setup TD's and QH */ ehci_setup_standard_chain(xfer, &sc->sc_async_p_last); /* put transfer on interrupt queue */ ehci_transfer_intr_enqueue(xfer); + + /* XXX Performance quirk: Some Host Controllers have a too low + * interrupt rate. Issue an IAAD to stimulate the Host + * Controller after queueing the BULK transfer. + */ + temp = EOREAD4(sc, EHCI_USBCMD); + if (!(temp & EHCI_CMD_IAAD)) + EOWRITE4(sc, EHCI_USBCMD, temp | EHCI_CMD_IAAD); } struct usb2_pipe_methods ehci_device_bulk_methods = |
