From 869aa98c1d6a03dd2078f8f8257a0bcc343cb8b9 Mon Sep 17 00:00:00 2001 From: Patrice Vilchez Date: Wed, 28 Apr 2010 13:45:40 +0200 Subject: [PATCH] USB: ohci-at91: fix power management hanging A hanging has been detected in ohci-at91 while going in suspend to ram. This is due to asynchronous operations between ohci reset and ohci clocks shutdown. This patch adds the reading of the control register between the reset of the ohci and clocks stop. This "flush the writes" idea was taken from ohci-hcd.c file (ohci_shutdown() function). Signed-off-by: Patrice Vilchez Signed-off-by: Nicolas Ferre Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ohci-at91.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/usb/host/ohci-at91.c b/drivers/usb/host/ohci-at91.c index 68b83ab70719..944291e10f97 100644 --- a/drivers/usb/host/ohci-at91.c +++ b/drivers/usb/host/ohci-at91.c @@ -331,6 +331,8 @@ ohci_hcd_at91_drv_suspend(struct platform_device *pdev, pm_message_t mesg) */ if (at91_suspend_entering_slow_clock()) { ohci_usb_reset (ohci); + /* flush the writes */ + (void) ohci_readl (ohci, &ohci->regs->control); at91_stop_clock(); } -- 2.20.1