usb: split usb_new_device for clarity and refactoring

This patch takes hub.c:usb_new_device() and splits it in three parts:

- The actual actions of adding a new device (quirk detection,
  announcement and autoresume tracking)

- Actual discovery and probing of the configuration and interfaces
  (split into __usb_configure_device())

- Configuration of the On-the-go parameters (split into
  __usb_configure_device_otg()).

The fundamental reasons for doing this split are clarity (smaller
functions are easier to maintain) and to allow part of the code to be
reused when authorizing devices to connect.

When a device is authorized connection, we need to run through the
hoops we didn't run when it was connected but not authorized, which is
basically parsing the configurations and probing
them. usb_configure_device() will do that for us.

Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 88 insertions, 48 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 34be27a6cbb4..65d9ea1e6d71 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1220,54 +1220,14 @@ static inline void show_string(struct usb_device *udev, char *id, char *string)
 #endif
 
 /**
- * usb_new_device - perform initial device setup (usbcore-internal)
+ * usb_configure_device_otg - FIXME (usbcore-internal)
  * @udev: newly addressed device (in ADDRESS state)
  *
- * This is called with devices which have been enumerated, but not yet
- * configured.  The device descriptor is available, but not descriptors
- * for any device configuration.  The caller must have locked either
- * the parent hub (if udev is a normal device) or else the
- * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
- * udev has already been installed, but udev is not yet visible through
- * sysfs or other filesystem code.
- *
- * It will return if the device is configured properly or not.  Zero if
- * the interface was registered with the driver core; else a negative
- * errno value.
- *
- * This call is synchronous, and may not be used in an interrupt context.
- *
- * Only the hub driver or root-hub registrar should ever call this.
+ * Do configuration for On-The-Go devices
  */
-int usb_new_device(struct usb_device *udev)
+static int usb_configure_device_otg(struct usb_device *udev)
 {
-        int err;
-
-        /* Determine quirks */
-        usb_detect_quirks(udev);
-
-        err = usb_get_configuration(udev);
-        if (err < 0) {
-                dev_err(&udev->dev, "can't read configurations, error %d\n",
-                        err);
-                goto fail;
-        }
-
-        /* read the standard strings and cache them if present */
-        udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
-        udev->manufacturer = usb_cache_string(udev,
-                        udev->descriptor.iManufacturer);
-        udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
-
-        /* Tell the world! */
-        dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
-                        "SerialNumber=%d\n",
-                        udev->descriptor.iManufacturer,
-                        udev->descriptor.iProduct,
-                        udev->descriptor.iSerialNumber);
-        show_string(udev, "Product", udev->product);
-        show_string(udev, "Manufacturer", udev->manufacturer);
-        show_string(udev, "SerialNumber", udev->serial);
+        int err = 0;
 
 #ifdef  CONFIG_USB_OTG
         /*
@@ -1329,8 +1289,82 @@ int usb_new_device(struct usb_device *udev)
                 err = -ENOTSUPP;
                 goto fail;
         }
+fail:
 #endif
+        return err;
+}
 
+
+/**
+ * usb_configure_device - Detect and probe device intfs/otg (usbcore-internal)
+ * @udev: newly addressed device (in ADDRESS state)
+ *
+ * This is only called by usb_new_device() and usb_authorize_device()
+ * and FIXME -- all comments that apply to them apply here wrt to
+ * environment.
+ *
+ * If the device is WUSB and not authorized, we don't attempt to read
+ * the string descriptors, as they will be errored out by the device
+ * until it has been authorized.
+ */
+static int usb_configure_device(struct usb_device *udev)
+{
+        int err;
+
+        if (udev->config == NULL) {
+                err = usb_get_configuration(udev);
+                if (err < 0) {
+                        dev_err(&udev->dev, "can't read configurations, error %d\n",
+                                err);
+                        goto fail;
+                }
+        }
+        if (udev->wusb == 1 && udev->authorized == 0) {
+                udev->product = kstrdup("n/a (unauthorized)", GFP_KERNEL);
+                udev->manufacturer = kstrdup("n/a (unauthorized)", GFP_KERNEL);
+                udev->serial = kstrdup("n/a (unauthorized)", GFP_KERNEL);
+        }
+        else {
+                /* read the standard strings and cache them if present */
+                udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
+                udev->manufacturer = usb_cache_string(udev,
+                                                      udev->descriptor.iManufacturer);
+                udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
+        }
+        err = usb_configure_device_otg(udev);
+fail:
+        return err;
+}
+
+
+/**
+ * usb_new_device - perform initial device setup (usbcore-internal)
+ * @udev: newly addressed device (in ADDRESS state)
+ *
+ * This is called with devices which have been enumerated, but not yet
+ * configured.  The device descriptor is available, but not descriptors
+ * for any device configuration.  The caller must have locked either
+ * the parent hub (if udev is a normal device) or else the
+ * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
+ * udev has already been installed, but udev is not yet visible through
+ * sysfs or other filesystem code.
+ *
+ * It will return if the device is configured properly or not.  Zero if
+ * the interface was registered with the driver core; else a negative
+ * errno value.
+ *
+ * This call is synchronous, and may not be used in an interrupt context.
+ *
+ * Only the hub driver or root-hub registrar should ever call this.
+ */
+int usb_new_device(struct usb_device *udev)
+{
+        int err;
+
+        usb_detect_quirks(udev);                /* Determine quirks */
+        err = usb_configure_device(udev);       /* detect & probe dev/intfs */
+        if (err < 0)
+                goto fail;
         /* export the usbdev device-node for libusb */
         udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
                         (((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
@@ -1346,17 +1380,23 @@ int usb_new_device(struct usb_device *udev)
         err = device_add(&udev->dev);
         if (err) {
                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
-                if (udev->parent)
-                        usb_autosuspend_device(udev->parent);
                 goto fail;
         }
 
-exit:
+        /* Tell the world! */
+        dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
+                "SerialNumber=%d\n",
+                udev->descriptor.iManufacturer,
+                udev->descriptor.iProduct,
+                udev->descriptor.iSerialNumber);
+        show_string(udev, "Product", udev->product);
+        show_string(udev, "Manufacturer", udev->manufacturer);
+        show_string(udev, "SerialNumber", udev->serial);
         return err;
 
 fail:
         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
-        goto exit;
+        return err;
 }
 
 static int hub_port_status(struct usb_hub *hub, int port1,