ar9170usb: fix hang on resume

This patch fixes a hang on resume when the filesystem is not
available and request_firmware blocks.

However, the device does not accept the firmware on resume.
and it will exit with:

> firmware part 1 upload failed (-71).
> device is in a bad state. please reconnect it!

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 90 insertions, 20 deletions

diff --git a/drivers/net/wireless/ar9170/usb.c b/drivers/net/wireless/ar9170/usb.c
index c9e422ead925..fddda477095c 100644
--- a/drivers/net/wireless/ar9170/usb.c
+++ b/drivers/net/wireless/ar9170/usb.c
@@ -623,6 +623,39 @@ static int ar9170_usb_open(struct ar9170 *ar)
         return 0;
 }
 
+static int ar9170_usb_init_device(struct ar9170_usb *aru)
+{
+        int err;
+
+        err = ar9170_usb_alloc_rx_irq_urb(aru);
+        if (err)
+                goto err_out;
+
+        err = ar9170_usb_alloc_rx_bulk_urbs(aru);
+        if (err)
+                goto err_unrx;
+
+        err = ar9170_usb_upload_firmware(aru);
+        if (err) {
+                err = ar9170_echo_test(&aru->common, 0x60d43110);
+                if (err) {
+                        /* force user invention, by disabling the device */
+                        err = usb_driver_set_configuration(aru->udev, -1);
+                        dev_err(&aru->udev->dev, "device is in a bad state. "
+                                                 "please reconnect it!\n");
+                        goto err_unrx;
+                }
+        }
+
+        return 0;
+
+err_unrx:
+        ar9170_usb_cancel_urbs(aru);
+
+err_out:
+        return err;
+}
+
 static int ar9170_usb_probe(struct usb_interface *intf,
                         const struct usb_device_id *id)
 {
@@ -658,32 +691,16 @@ static int ar9170_usb_probe(struct usb_interface *intf,
 
         err = ar9170_usb_reset(aru);
         if (err)
-                goto err_unlock;
+                goto err_freehw;
 
         err = ar9170_usb_request_firmware(aru);
         if (err)
-                goto err_unlock;
+                goto err_freehw;
 
-        err = ar9170_usb_alloc_rx_irq_urb(aru);
+        err = ar9170_usb_init_device(aru);
         if (err)
                 goto err_freefw;
 
-        err = ar9170_usb_alloc_rx_bulk_urbs(aru);
-        if (err)
-                goto err_unrx;
-
-        err = ar9170_usb_upload_firmware(aru);
-        if (err) {
-                err = ar9170_echo_test(&aru->common, 0x60d43110);
-                if (err) {
-                        /* force user invention, by disabling the device */
-                        err = usb_driver_set_configuration(aru->udev, -1);
-                        dev_err(&aru->udev->dev, "device is in a bad state. "
-                                                 "please reconnect it!\n");
-                        goto err_unrx;
-                }
-        }
-
         err = ar9170_usb_open(ar);
         if (err)
                 goto err_unrx;
@@ -703,7 +720,7 @@ err_freefw:
         release_firmware(aru->init_values);
         release_firmware(aru->firmware);
 
-err_unlock:
+err_freehw:
         usb_set_intfdata(intf, NULL);
         usb_put_dev(udev);
         ieee80211_free_hw(ar->hw);
@@ -730,12 +747,65 @@ static void ar9170_usb_disconnect(struct usb_interface *intf)
         ieee80211_free_hw(aru->common.hw);
 }
 
+#ifdef CONFIG_PM
+static int ar9170_suspend(struct usb_interface *intf,
+                          pm_message_t  message)
+{
+        struct ar9170_usb *aru = usb_get_intfdata(intf);
+
+        if (!aru)
+                return -ENODEV;
+
+        aru->common.state = AR9170_IDLE;
+        ar9170_usb_cancel_urbs(aru);
+
+        return 0;
+}
+
+static int ar9170_resume(struct usb_interface *intf)
+{
+        struct ar9170_usb *aru = usb_get_intfdata(intf);
+        int err;
+
+        if (!aru)
+                return -ENODEV;
+
+        usb_unpoison_anchored_urbs(&aru->rx_submitted);
+        usb_unpoison_anchored_urbs(&aru->tx_submitted);
+
+        /*
+         * FIXME: firmware upload will fail on resume.
+         * but this is better than a hang!
+         */
+
+        err = ar9170_usb_init_device(aru);
+        if (err)
+                goto err_unrx;
+
+        err = ar9170_usb_open(&aru->common);
+        if (err)
+                goto err_unrx;
+
+        return 0;
+
+err_unrx:
+        aru->common.state = AR9170_IDLE;
+        ar9170_usb_cancel_urbs(aru);
+
+        return err;
+}
+#endif /* CONFIG_PM */
+
 static struct usb_driver ar9170_driver = {
         .name = "ar9170usb",
         .probe = ar9170_usb_probe,
         .disconnect = ar9170_usb_disconnect,
         .id_table = ar9170_usb_ids,
         .soft_unbind = 1,
+#ifdef CONFIG_PM
+        .suspend = ar9170_suspend,
+        .resume = ar9170_resume,
+#endif /* CONFIG_PM */
 };
 
 static int __init ar9170_init(void)