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path: root/drivers/usb/host/uhci-hub.c
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Diffstat (limited to 'drivers/usb/host/uhci-hub.c')
-rw-r--r--drivers/usb/host/uhci-hub.c12
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/usb/host/uhci-hub.c b/drivers/usb/host/uhci-hub.c
index c545ef9..16fb72e 100644
--- a/drivers/usb/host/uhci-hub.c
+++ b/drivers/usb/host/uhci-hub.c
@@ -84,6 +84,7 @@ static void uhci_finish_suspend(struct uhci_hcd *uhci, int port,
unsigned long port_addr)
{
int status;
+ int i;
if (inw(port_addr) & (USBPORTSC_SUSP | USBPORTSC_RD)) {
CLR_RH_PORTSTAT(USBPORTSC_SUSP | USBPORTSC_RD);
@@ -92,9 +93,14 @@ static void uhci_finish_suspend(struct uhci_hcd *uhci, int port,
/* The controller won't actually turn off the RD bit until
* it has had a chance to send a low-speed EOP sequence,
- * which takes 3 bit times (= 2 microseconds). We'll delay
- * slightly longer for good luck. */
- udelay(4);
+ * which is supposed to take 3 bit times (= 2 microseconds).
+ * 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))
+ break;
+ udelay(1);
+ }
}
clear_bit(port, &uhci->resuming_ports);
}
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