On 13 December 2013 21:55, Marek Vasut marex@denx.de wrote:
The detection function of the EHCI PCI controller was really cryptic, add a beefy comment and clean the portion of the code up a bit. No change in the logic of the code.
Signed-off-by: Marek Vasut marex@denx.de Cc: Simon Glass sjg@chromium.org
Acked-by: Simon Glass sjg@chromium.org
drivers/usb/host/ehci-pci.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c index 7a1ffe5..991b199 100644 --- a/drivers/usb/host/ehci-pci.c +++ b/drivers/usb/host/ehci-pci.c @@ -54,9 +54,31 @@ static pci_dev_t ehci_find_class(int index) bdf += PCI_BDF(0, 0, 1)) { pci_read_config_dword(bdf, PCI_CLASS_REVISION, &class);
if ((class >> 8 == PCI_CLASS_SERIAL_USB_EHCI)&& !index--)return bdf;
class >>= 8;/** Here be dragons! In case we have multiple* PCI EHCI controllers, this function will* be called multiple times as well. This* function will scan the PCI busses, always* starting from bus 0, device 0, function 0,* until it finds an USB controller. The USB* stack gives us an 'index' of a controller* that is currently being registered, which* is a number, starting from 0 and growing* in ascending order as controllers are added.* To avoid probing the same controller in tne* subsequent runs of this function, we will* skip 'index - 1' detected controllers and* report the index'th controller.*/if (class != PCI_CLASS_SERIAL_USB_EHCI)continue;if (index) {index--;continue;}/* Return index'th controller. */return bdf; } } }-- 1.8.4.3