Without suspend/resume functionality in the USB driver the USB core
will disconnect and reconnect the DLN2 port and because the GPIO
framework does not yet support removal of an in-use controller a
suspend/resume operation will result in a crash.

This patch provides suspend and resume functions for the DLN2 driver
so that the above scenario is avoided.

Signed-off-by: Octavian Purdila <octavian.purd...@intel.com>
---
 drivers/mfd/dln2.c | 41 ++++++++++++++++++++++++++++++++++++++---
 1 file changed, 38 insertions(+), 3 deletions(-)

diff --git a/drivers/mfd/dln2.c b/drivers/mfd/dln2.c
index 6d49685..08c403c 100644
--- a/drivers/mfd/dln2.c
+++ b/drivers/mfd/dln2.c
@@ -587,7 +587,6 @@ static void dln2_free_rx_urbs(struct dln2_dev *dln2)
        int i;
 
        for (i = 0; i < DLN2_MAX_URBS; i++) {
-               usb_kill_urb(dln2->rx_urb[i]);
                usb_free_urb(dln2->rx_urb[i]);
                kfree(dln2->rx_buf[i]);
        }
@@ -665,9 +664,8 @@ static const struct mfd_cell dln2_devs[] = {
        },
 };
 
-static void dln2_disconnect(struct usb_interface *interface)
+static void dln2_stop(struct dln2_dev *dln2)
 {
-       struct dln2_dev *dln2 = usb_get_intfdata(interface);
        int i, j;
 
        /* don't allow starting new transfers */
@@ -696,6 +694,16 @@ static void dln2_disconnect(struct usb_interface 
*interface)
        /* wait for transfers to end */
        wait_event(dln2->disconnect_wq, !dln2->active_transfers);
 
+       for (i = 0; i < DLN2_MAX_URBS; i++)
+               usb_kill_urb(dln2->rx_urb[i]);
+}
+
+static void dln2_disconnect(struct usb_interface *interface)
+{
+       struct dln2_dev *dln2 = usb_get_intfdata(interface);
+
+       dln2_stop(dln2);
+
        mfd_remove_devices(&interface->dev);
 
        dln2_free(dln2);
@@ -767,11 +775,38 @@ static const struct usb_device_id dln2_table[] = {
 
 MODULE_DEVICE_TABLE(usb, dln2_table);
 
+static int dln2_suspend(struct usb_interface *iface, pm_message_t message)
+{
+       struct dln2_dev *dln2 = usb_get_intfdata(iface);
+
+       dln2_stop(dln2);
+       return 0;
+}
+
+static int dln2_resume(struct usb_interface *iface)
+{
+       struct dln2_dev *dln2 = usb_get_intfdata(iface);
+       int i;
+       int ret = 0;
+
+       dln2->disconnect = false;
+
+       for (i = 0; i < DLN2_MAX_URBS; i++) {
+               ret = usb_submit_urb(dln2->rx_urb[i], GFP_KERNEL);
+               if (ret)
+                       break;
+       }
+
+       return ret;
+}
+
 static struct usb_driver dln2_driver = {
        .name = "dln2",
        .probe = dln2_probe,
        .disconnect = dln2_disconnect,
        .id_table = dln2_table,
+       .suspend = dln2_suspend,
+       .resume = dln2_resume,
 };
 
 module_usb_driver(dln2_driver);
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to