Intel EG20T USB host controller does not send SOF in resuming time after
suspending, if the FLR bit was not cleared. When pen drive is attached,
the controller has a long resuming time to try re-connect it.
This patch clear the FLR bit in suspending time for fixing the issue.
Signed-off-by: Tomoya MORINAGA <tomoya.r...@gmail.com>
---
v3: Update comments from Alan Stern
Add comment in the source code.
v2: Update comments from Alan Stern
Add patch description
Always clear the STS_FLR flag.
---
drivers/usb/host/ehci-hub.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index fc9e7cc..278b589 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -318,6 +318,13 @@ static int ehci_bus_suspend (struct usb_hcd *hcd)
ehci_readl(ehci, &ehci->regs->intr_enable);
ehci->next_statechange = jiffies + msecs_to_jiffies(10);
+
+ /* Intel EG20T USB host controller does not send SOF
+ * in resuming time after suspending, if the FLR bit was not cleared.
+ * Therefore clear the FLR bit in here.
+ */
+ ehci_writel(ehci, STS_FLR, &ehci->regs->status);
+
spin_unlock_irq (&ehci->lock);
/* ehci_work() may have re-enabled the watchdog timer, which we do not
--
1.7.4.4
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