ar9170: load firmware asynchronously

This converts ar9170 to load firmware asynchronously
out of ->probe() and only register with mac80211 when
all firmware has been loaded successfully. If, on the
other hand, any firmware fails to load, it will now
unbind from the device.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 111 insertions, 70 deletions

diff --git a/drivers/net/wireless/ath/ar9170/ar9170.h b/drivers/net/wireless/ath/ar9170/ar9170.h
index 8c8ce67971e9..dc662b76a1c8 100644
--- a/drivers/net/wireless/ath/ar9170/ar9170.h
+++ b/drivers/net/wireless/ath/ar9170/ar9170.h
@@ -166,6 +166,7 @@ struct ar9170 {
         struct ath_common common;
         struct mutex mutex;
         enum ar9170_device_state state;
+        bool registered;
         unsigned long bad_hw_nagger;
 
         int (*open)(struct ar9170 *);
diff --git a/drivers/net/wireless/ath/ar9170/main.c b/drivers/net/wireless/ath/ar9170/main.c
index 8a964f130367..f4650fcdebc9 100644
--- a/drivers/net/wireless/ath/ar9170/main.c
+++ b/drivers/net/wireless/ath/ar9170/main.c
@@ -2701,7 +2701,8 @@ int ar9170_register(struct ar9170 *ar, struct device *pdev)
         dev_info(pdev, "Atheros AR9170 is registered as '%s'\n",
                  wiphy_name(ar->hw->wiphy));
 
-        return err;
+        ar->registered = true;
+        return 0;
 
 err_unreg:
         ieee80211_unregister_hw(ar->hw);
@@ -2712,11 +2713,14 @@ err_out:
 
 void ar9170_unregister(struct ar9170 *ar)
 {
+        if (ar->registered) {
 #ifdef CONFIG_AR9170_LEDS
-        ar9170_unregister_leds(ar);
+                ar9170_unregister_leds(ar);
 #endif /* CONFIG_AR9170_LEDS */
 
-        kfree_skb(ar->rx_failover);
         ieee80211_unregister_hw(ar->hw);
+        }
+
+        kfree_skb(ar->rx_failover);
         mutex_destroy(&ar->mutex);
 }
diff --git a/drivers/net/wireless/ath/ar9170/usb.c b/drivers/net/wireless/ath/ar9170/usb.c
index 0f361186b78f..4e30197afff6 100644
--- a/drivers/net/wireless/ath/ar9170/usb.c
+++ b/drivers/net/wireless/ath/ar9170/usb.c
@@ -582,43 +582,6 @@ static int ar9170_usb_upload(struct ar9170_usb *aru, const void *data,
         return 0;
 }
 
-static int ar9170_usb_request_firmware(struct ar9170_usb *aru)
-{
-        int err = 0;
-
-        err = request_firmware(&aru->firmware, "ar9170.fw",
-                               &aru->udev->dev);
-        if (!err) {
-                aru->init_values = NULL;
-                return 0;
-        }
-
-        if (aru->req_one_stage_fw) {
-                dev_err(&aru->udev->dev, "ar9170.fw firmware file "
-                        "not found and is required for this device\n");
-                return -EINVAL;
-        }
-
-        dev_err(&aru->udev->dev, "ar9170.fw firmware file "
-                "not found, trying old firmware...\n");
-
-        err = request_firmware(&aru->init_values, "ar9170-1.fw",
-                               &aru->udev->dev);
-        if (err) {
-                dev_err(&aru->udev->dev, "file with init values not found.\n");
-                return err;
-        }
-
-        err = request_firmware(&aru->firmware, "ar9170-2.fw", &aru->udev->dev);
-        if (err) {
-                release_firmware(aru->init_values);
-                dev_err(&aru->udev->dev, "firmware file not found.\n");
-                return err;
-        }
-
-        return err;
-}
-
 static int ar9170_usb_reset(struct ar9170_usb *aru)
 {
         int ret, lock = (aru->intf->condition != USB_INTERFACE_BINDING);
@@ -757,6 +720,103 @@ err_out:
         return err;
 }
 
+static void ar9170_usb_firmware_failed(struct ar9170_usb *aru)
+{
+        struct device *parent = aru->udev->dev.parent;
+
+        /* unbind anything failed */
+        if (parent)
+                down(&parent->sem);
+        device_release_driver(&aru->udev->dev);
+        if (parent)
+                up(&parent->sem);
+}
+
+static void ar9170_usb_firmware_finish(const struct firmware *fw, void *context)
+{
+        struct ar9170_usb *aru = context;
+        int err;
+
+        aru->firmware = fw;
+
+        if (!fw) {
+                dev_err(&aru->udev->dev, "firmware file not found.\n");
+                goto err_freefw;
+        }
+
+        err = ar9170_usb_init_device(aru);
+        if (err)
+                goto err_freefw;
+
+        err = ar9170_usb_open(&aru->common);
+        if (err)
+                goto err_unrx;
+
+        err = ar9170_register(&aru->common, &aru->udev->dev);
+
+        ar9170_usb_stop(&aru->common);
+        if (err)
+                goto err_unrx;
+
+        return;
+
+ err_unrx:
+        ar9170_usb_cancel_urbs(aru);
+
+ err_freefw:
+        ar9170_usb_firmware_failed(aru);
+}
+
+static void ar9170_usb_firmware_inits(const struct firmware *fw,
+                                      void *context)
+{
+        struct ar9170_usb *aru = context;
+        int err;
+
+        if (!fw) {
+                dev_err(&aru->udev->dev, "file with init values not found.\n");
+                ar9170_usb_firmware_failed(aru);
+                return;
+        }
+
+        aru->init_values = fw;
+
+        /* ok so we have the init values -- get code for two-stage */
+
+        err = request_firmware_nowait(THIS_MODULE, 1, "ar9170-2.fw",
+                                      &aru->udev->dev, GFP_KERNEL, aru,
+                                      ar9170_usb_firmware_finish);
+        if (err)
+                ar9170_usb_firmware_failed(aru);
+}
+
+static void ar9170_usb_firmware_step2(const struct firmware *fw, void *context)
+{
+        struct ar9170_usb *aru = context;
+        int err;
+
+        if (fw) {
+                ar9170_usb_firmware_finish(fw, context);
+                return;
+        }
+
+        if (aru->req_one_stage_fw) {
+                dev_err(&aru->udev->dev, "ar9170.fw firmware file "
+                        "not found and is required for this device\n");
+                ar9170_usb_firmware_failed(aru);
+                return;
+        }
+
+        dev_err(&aru->udev->dev, "ar9170.fw firmware file "
+                "not found, trying old firmware...\n");
+
+        err = request_firmware_nowait(THIS_MODULE, 1, "ar9170-1.fw",
+                                      &aru->udev->dev, GFP_KERNEL, aru,
+                                      ar9170_usb_firmware_inits);
+        if (err)
+                ar9170_usb_firmware_failed(aru);
+}
+
 static bool ar9170_requires_one_stage(const struct usb_device_id *id)
 {
         if (!id->driver_info)
@@ -814,33 +874,9 @@ static int ar9170_usb_probe(struct usb_interface *intf,
         if (err)
                 goto err_freehw;
 
-        err = ar9170_usb_request_firmware(aru);
-        if (err)
-                goto err_freehw;
-
-        err = ar9170_usb_init_device(aru);
-        if (err)
-                goto err_freefw;
-
-        err = ar9170_usb_open(ar);
-        if (err)
-                goto err_unrx;
-
-        err = ar9170_register(ar, &udev->dev);
-
-        ar9170_usb_stop(ar);
-        if (err)
-                goto err_unrx;
-
-        return 0;
-
-err_unrx:
-        ar9170_usb_cancel_urbs(aru);
-
-err_freefw:
-        release_firmware(aru->init_values);
-        release_firmware(aru->firmware);
-
+        return request_firmware_nowait(THIS_MODULE, 1, "ar9170.fw",
+                                       &aru->udev->dev, GFP_KERNEL, aru,
+                                       ar9170_usb_firmware_step2);
 err_freehw:
         usb_set_intfdata(intf, NULL);
         usb_put_dev(udev);
@@ -860,12 +896,12 @@ static void ar9170_usb_disconnect(struct usb_interface *intf)
         ar9170_unregister(&aru->common);
         ar9170_usb_cancel_urbs(aru);
 
-        release_firmware(aru->init_values);
-        release_firmware(aru->firmware);
-
         usb_put_dev(aru->udev);
         usb_set_intfdata(intf, NULL);
         ieee80211_free_hw(aru->common.hw);
+
+        release_firmware(aru->init_values);
+        release_firmware(aru->firmware);
 }
 
 #ifdef CONFIG_PM