USB: ohci-at91: add a reset function to fix race condition

commit 07e4e556eff4938eb2edf2591de3aa7d7fb82b52 upstream.

A possible race condition appears because we are not initializing
the ohci->regs before calling usb_hcd_request_irqs().
We move the call to ohci_init() in hcd->driver->reset() instead of
hcd->driver->start() to fix this.
This was experienced when we share the same IRQ line between OHCI and EHCI
controllers.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Tested-by: Christian Eggers <christian.eggers@kathrein.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/usb/host/ohci-at91.c b/drivers/usb/host/ohci-at91.c
index 95a9fec38e89b4e8a6daff8a3c0c75fd73315d4c..a60c7aa8f7dfec9bdbc0724084f0065f0fcd130e 100644 (file)
--- a/drivers/usb/host/ohci-at91.c
+++ b/drivers/usb/host/ohci-at91.c
@@ -199,7 +199,7 @@ static void usb_hcd_at91_remove(struct usb_hcd *hcd,
 /*-------------------------------------------------------------------------*/
 
 static int __devinit
-ohci_at91_start (struct usb_hcd *hcd)
+ohci_at91_reset (struct usb_hcd *hcd)
 {
        struct at91_usbh_data   *board = hcd->self.controller->platform_data;
        struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
@@ -209,6 +209,14 @@ ohci_at91_start (struct usb_hcd *hcd)
                return ret;
 
        ohci->num_ports = board->ports;
+       return 0;
+}
+
+static int __devinit
+ohci_at91_start (struct usb_hcd *hcd)
+{
+       struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
+       int                     ret;
 
        if ((ret = ohci_run(ohci)) < 0) {
                err("can't start %s", hcd->self.bus_name);
@@ -390,6 +398,7 @@ static const struct hc_driver ohci_at91_hc_driver = {
        /*
         * basic lifecycle operations
         */
+       .reset =                ohci_at91_reset,
        .start =                ohci_at91_start,
        .stop =                 ohci_stop,
        .shutdown =             ohci_shutdown,