diff options
Diffstat (limited to 'src/drivers/usb/ehci.c')
| -rw-r--r-- | src/drivers/usb/ehci.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/src/drivers/usb/ehci.c b/src/drivers/usb/ehci.c index e847c6b7..516ffd8c 100644 --- a/src/drivers/usb/ehci.c +++ b/src/drivers/usb/ehci.c @@ -337,6 +337,32 @@ static void ehci_poll_companions ( struct ehci_device *ehci ) { } } +/** + * Locate EHCI companion controller + * + * @v pci PCI device + * @ret busdevfn EHCI companion controller bus:dev.fn (if any) + */ +unsigned int ehci_companion ( struct pci_device *pci ) { + struct pci_device tmp; + unsigned int busdevfn; + int rc; + + /* Look for an EHCI function on the same PCI device */ + busdevfn = pci->busdevfn; + while ( ++busdevfn <= PCI_LAST_FUNC ( pci->busdevfn ) ) { + pci_init ( &tmp, busdevfn ); + if ( ( rc = pci_read_config ( &tmp ) ) != 0 ) + continue; + if ( tmp.class == PCI_CLASS ( PCI_CLASS_SERIAL, + PCI_CLASS_SERIAL_USB, + PCI_CLASS_SERIAL_USB_EHCI ) ) + return busdevfn; + } + + return 0; +} + /****************************************************************************** * * Run / stop / reset |