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USB: EHCI: clear PHCD before resuming

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This is a bug fix for PHCD (phy clock disable) low power feature:
After PHCD is set, any write to PORTSC register is illegal, so when
resume ports, clear PHCD bit first.

Signed-off-by: Alek Du <alek.du@intel.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alek Du 2010-05-10 11:17:49 +08:00 committed by Greg Kroah-Hartman
parent 17b2765ef8
commit eab80de01c
1 changed files with 17 additions and 0 deletions
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17
drivers/usb/host/ehci-hub.c
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@ -294,6 +294,16 @@ static int ehci_bus_resume (struct usb_hcd *hcd)
/* manually resume the ports we suspended during bus_suspend() */
i = HCS_N_PORTS (ehci->hcs_params);
while (i--) {
/* clear phy low power mode before resume */
if (ehci->has_hostpc) {
u32 __iomem *hostpc_reg =
(u32 __iomem *)((u8 *)ehci->regs
+ HOSTPC0 + 4 * (i & 0xff));
temp = ehci_readl(ehci, hostpc_reg);
ehci_writel(ehci, temp & ~HOSTPC_PHCD,
hostpc_reg);
mdelay(5);
}
temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
if (test_bit(i, &ehci->bus_suspended) &&
@ -678,6 +688,13 @@ static int ehci_hub_control (
if (temp & PORT_SUSPEND) {
if ((temp & PORT_PE) == 0)
goto error;
/* clear phy low power mode before resume */
if (hostpc_reg) {
temp1 = ehci_readl(ehci, hostpc_reg);
ehci_writel(ehci, temp1 & ~HOSTPC_PHCD,
hostpc_reg);
mdelay(5);
}
/* resume signaling for 20 msec */
temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
ehci_writel(ehci, temp | PORT_RESUME,