4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Marc Ohlf <[email protected]> commit bc337b51508beb2d039aff5074a76cfe1c212030 upstream. In ehci_turn_off_all_ports() all EHCI port registers are cleared to zero. On some hardware, this can lead to an system hang, when ehci_port_power() accesses the already cleared registers. This patch changes the order of cleanup. First call ehci_port_power() which respects the current bits in port status registers and afterwards cleanup the hard way by setting everything to zero. Signed-off-by: Marc Ohlf <[email protected]> Acked-by: Alan Stern <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/usb/host/ehci-hcd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -332,11 +332,11 @@ static void ehci_turn_off_all_ports(stru int port = HCS_N_PORTS(ehci->hcs_params); while (port--) { - ehci_writel(ehci, PORT_RWC_BITS, - &ehci->regs->port_status[port]); spin_unlock_irq(&ehci->lock); ehci_port_power(ehci, port, false); spin_lock_irq(&ehci->lock); + ehci_writel(ehci, PORT_RWC_BITS, + &ehci->regs->port_status[port]); } }
