From: Alan Stern This patch (as863) fixes a problem encountered sometimes when resuming a port on a UHCI controller. The hardware may turn off the Resume-Detect bit before turning off the Suspend bit, leading usbcore to think that the port is still suspended and the resume has failed. The patch makes uhci_finish_suspend() wait until both bits are safely off. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/uhci-hub.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) --- linux-2.6.20.1.orig/drivers/usb/host/uhci-hub.c +++ linux-2.6.20.1/drivers/usb/host/uhci-hub.c @@ -33,6 +33,9 @@ static __u8 root_hub_hub_des[] = /* status change bits: nonzero writes will clear */ #define RWC_BITS (USBPORTSC_OCC | USBPORTSC_PEC | USBPORTSC_CSC) +/* suspend/resume bits: port suspended or port resuming */ +#define SUSPEND_BITS (USBPORTSC_SUSP | USBPORTSC_RD) + /* A port that either is connected or has a changed-bit set will prevent * us from AUTO_STOPPING. */ @@ -96,8 +99,8 @@ static void uhci_finish_suspend(struct u int status; int i; - if (inw(port_addr) & (USBPORTSC_SUSP | USBPORTSC_RD)) { - CLR_RH_PORTSTAT(USBPORTSC_SUSP | USBPORTSC_RD); + if (inw(port_addr) & SUSPEND_BITS) { + CLR_RH_PORTSTAT(SUSPEND_BITS); if (test_bit(port, &uhci->resuming_ports)) set_bit(port, &uhci->port_c_suspend); @@ -107,7 +110,7 @@ static void uhci_finish_suspend(struct u * Experiments show that some controllers take longer, so * we'll poll for completion. */ for (i = 0; i < 10; ++i) { - if (!(inw(port_addr) & USBPORTSC_RD)) + if (!(inw(port_addr) & SUSPEND_BITS)) break; udelay(1); } @@ -289,7 +292,7 @@ static int uhci_hub_control(struct usb_h wPortStatus |= USB_PORT_STAT_CONNECTION; if (status & USBPORTSC_PE) { wPortStatus |= USB_PORT_STAT_ENABLE; - if (status & (USBPORTSC_SUSP | USBPORTSC_RD)) + if (status & SUSPEND_BITS) wPortStatus |= USB_PORT_STAT_SUSPEND; } if (status & USBPORTSC_OC) -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/