1 files changed, 140 insertions, 24 deletions

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 6d1048faf08e..de51667dd64d 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -18,6 +18,8 @@
 #include "hcd.h"        /* for usbcore internals */
 #include "usb.h"
 
+static void cancel_async_set_config(struct usb_device *udev);
+
 struct api_context {
         struct completion       done;
         int                     status;
@@ -139,9 +141,9 @@ int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request,
 
         dr->bRequestType = requesttype;
         dr->bRequest = request;
-        dr->wValue = cpu_to_le16p(&value);
-        dr->wIndex = cpu_to_le16p(&index);
-        dr->wLength = cpu_to_le16p(&size);
+        dr->wValue = cpu_to_le16(value);
+        dr->wIndex = cpu_to_le16(index);
+        dr->wLength = cpu_to_le16(size);
 
         /* dbg("usb_control_msg"); */
 
@@ -1004,6 +1006,34 @@ int usb_clear_halt(struct usb_device *dev, int pipe)
 }
 EXPORT_SYMBOL_GPL(usb_clear_halt);
 
+static int create_intf_ep_devs(struct usb_interface *intf)
+{
+        struct usb_device *udev = interface_to_usbdev(intf);
+        struct usb_host_interface *alt = intf->cur_altsetting;
+        int i;
+
+        if (intf->ep_devs_created || intf->unregistering)
+                return 0;
+
+        for (i = 0; i < alt->desc.bNumEndpoints; ++i)
+                (void) usb_create_ep_devs(&intf->dev, &alt->endpoint[i], udev);
+        intf->ep_devs_created = 1;
+        return 0;
+}
+
+static void remove_intf_ep_devs(struct usb_interface *intf)
+{
+        struct usb_host_interface *alt = intf->cur_altsetting;
+        int i;
+
+        if (!intf->ep_devs_created)
+                return;
+
+        for (i = 0; i < alt->desc.bNumEndpoints; ++i)
+                usb_remove_ep_devs(&alt->endpoint[i]);
+        intf->ep_devs_created = 0;
+}
+
 /**
  * usb_disable_endpoint -- Disable an endpoint by address
  * @dev: the device whose endpoint is being disabled
@@ -1092,7 +1122,7 @@ void usb_disable_device(struct usb_device *dev, int skip_ep0)
                         dev_dbg(&dev->dev, "unregistering interface %s\n",
                                 dev_name(&interface->dev));
                         interface->unregistering = 1;
-                        usb_remove_sysfs_intf_files(interface);
+                        remove_intf_ep_devs(interface);
                         device_del(&interface->dev);
                 }
 
@@ -1113,22 +1143,26 @@ void usb_disable_device(struct usb_device *dev, int skip_ep0)
  * usb_enable_endpoint - Enable an endpoint for USB communications
  * @dev: the device whose interface is being enabled
  * @ep: the endpoint
+ * @reset_toggle: flag to set the endpoint's toggle back to 0
  *
- * Resets the endpoint toggle, and sets dev->ep_{in,out} pointers.
+ * Resets the endpoint toggle if asked, and sets dev->ep_{in,out} pointers.
  * For control endpoints, both the input and output sides are handled.
  */
-void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep)
+void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep,
+                bool reset_toggle)
 {
         int epnum = usb_endpoint_num(&ep->desc);
         int is_out = usb_endpoint_dir_out(&ep->desc);
         int is_control = usb_endpoint_xfer_control(&ep->desc);
 
         if (is_out || is_control) {
-                usb_settoggle(dev, epnum, 1, 0);
+                if (reset_toggle)
+                        usb_settoggle(dev, epnum, 1, 0);
                 dev->ep_out[epnum] = ep;
         }
         if (!is_out || is_control) {
-                usb_settoggle(dev, epnum, 0, 0);
+                if (reset_toggle)
+                        usb_settoggle(dev, epnum, 0, 0);
                 dev->ep_in[epnum] = ep;
         }
         ep->enabled = 1;
@@ -1138,17 +1172,18 @@ void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep)
  * usb_enable_interface - Enable all the endpoints for an interface
  * @dev: the device whose interface is being enabled
  * @intf: pointer to the interface descriptor
+ * @reset_toggles: flag to set the endpoints' toggles back to 0
  *
  * Enables all the endpoints for the interface's current altsetting.
  */
-static void usb_enable_interface(struct usb_device *dev,
-                                 struct usb_interface *intf)
+void usb_enable_interface(struct usb_device *dev,
+                struct usb_interface *intf, bool reset_toggles)
 {
         struct usb_host_interface *alt = intf->cur_altsetting;
         int i;
 
         for (i = 0; i < alt->desc.bNumEndpoints; ++i)
-                usb_enable_endpoint(dev, &alt->endpoint[i]);
+                usb_enable_endpoint(dev, &alt->endpoint[i], reset_toggles);
 }
 
 /**
@@ -1235,8 +1270,10 @@ int usb_set_interface(struct usb_device *dev, int interface, int alternate)
          */
 
         /* prevent submissions using previous endpoint settings */
-        if (iface->cur_altsetting != alt)
+        if (iface->cur_altsetting != alt) {
+                remove_intf_ep_devs(iface);
                 usb_remove_sysfs_intf_files(iface);
+        }
         usb_disable_interface(dev, iface);
 
         iface->cur_altsetting = alt;
@@ -1271,10 +1308,11 @@ int usb_set_interface(struct usb_device *dev, int interface, int alternate)
          * during the SETUP stage - hence EP0 toggles are "don't care" here.
          * (Likewise, EP0 never "halts" on well designed devices.)
          */
-        usb_enable_interface(dev, iface);
-        if (device_is_registered(&iface->dev))
+        usb_enable_interface(dev, iface, true);
+        if (device_is_registered(&iface->dev)) {
                 usb_create_sysfs_intf_files(iface);
-
+                create_intf_ep_devs(iface);
+        }
         return 0;
 }
 EXPORT_SYMBOL_GPL(usb_set_interface);
@@ -1334,7 +1372,6 @@ int usb_reset_configuration(struct usb_device *dev)
                 struct usb_interface *intf = config->interface[i];
                 struct usb_host_interface *alt;
 
-                usb_remove_sysfs_intf_files(intf);
                 alt = usb_altnum_to_altsetting(intf, 0);
 
                 /* No altsetting 0?  We'll assume the first altsetting.
@@ -1345,10 +1382,16 @@ int usb_reset_configuration(struct usb_device *dev)
                 if (!alt)
                         alt = &intf->altsetting[0];
 
+                if (alt != intf->cur_altsetting) {
+                        remove_intf_ep_devs(intf);
+                        usb_remove_sysfs_intf_files(intf);
+                }
                 intf->cur_altsetting = alt;
-                usb_enable_interface(dev, intf);
-                if (device_is_registered(&intf->dev))
+                usb_enable_interface(dev, intf, true);
+                if (device_is_registered(&intf->dev)) {
                         usb_create_sysfs_intf_files(intf);
+                        create_intf_ep_devs(intf);
+                }
         }
         return 0;
 }
@@ -1441,6 +1484,46 @@ static struct usb_interface_assoc_descriptor *find_iad(struct usb_device *dev,
         return retval;
 }
 
+
+/*
+ * Internal function to queue a device reset
+ *
+ * This is initialized into the workstruct in 'struct
+ * usb_device->reset_ws' that is launched by
+ * message.c:usb_set_configuration() when initializing each 'struct
+ * usb_interface'.
+ *
+ * It is safe to get the USB device without reference counts because
+ * the life cycle of @iface is bound to the life cycle of @udev. Then,
+ * this function will be ran only if @iface is alive (and before
+ * freeing it any scheduled instances of it will have been cancelled).
+ *
+ * We need to set a flag (usb_dev->reset_running) because when we call
+ * the reset, the interfaces might be unbound. The current interface
+ * cannot try to remove the queued work as it would cause a deadlock
+ * (you cannot remove your work from within your executing
+ * workqueue). This flag lets it know, so that
+ * usb_cancel_queued_reset() doesn't try to do it.
+ *
+ * See usb_queue_reset_device() for more details
+ */
+void __usb_queue_reset_device(struct work_struct *ws)
+{
+        int rc;
+        struct usb_interface *iface =
+                container_of(ws, struct usb_interface, reset_ws);
+        struct usb_device *udev = interface_to_usbdev(iface);
+
+        rc = usb_lock_device_for_reset(udev, iface);
+        if (rc >= 0) {
+                iface->reset_running = 1;
+                usb_reset_device(udev);
+                iface->reset_running = 0;
+                usb_unlock_device(udev);
+        }
+}
+
+
 /*
  * usb_set_configuration - Makes a particular device setting be current
  * @dev: the device whose configuration is being updated
@@ -1560,6 +1643,9 @@ free_interfaces:
         if (dev->state != USB_STATE_ADDRESS)
                 usb_disable_device(dev, 1);     /* Skip ep0 */
 
+        /* Get rid of pending async Set-Config requests for this device */
+        cancel_async_set_config(dev);
+
         ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                               USB_REQ_SET_CONFIGURATION, 0, configuration, 0,
                               NULL, 0, USB_CTRL_SET_TIMEOUT);
@@ -1604,13 +1690,14 @@ free_interfaces:
                         alt = &intf->altsetting[0];
 
                 intf->cur_altsetting = alt;
-                usb_enable_interface(dev, intf);
+                usb_enable_interface(dev, intf, true);
                 intf->dev.parent = &dev->dev;
                 intf->dev.driver = NULL;
                 intf->dev.bus = &usb_bus_type;
                 intf->dev.type = &usb_if_device_type;
                 intf->dev.groups = usb_interface_groups;
                 intf->dev.dma_mask = dev->dev.dma_mask;
+                INIT_WORK(&intf->reset_ws, __usb_queue_reset_device);
                 device_initialize(&intf->dev);
                 mark_quiesced(intf);
                 dev_set_name(&intf->dev, "%d-%s:%d.%d",
@@ -1641,17 +1728,21 @@ free_interfaces:
                                 dev_name(&intf->dev), ret);
                         continue;
                 }
-                usb_create_sysfs_intf_files(intf);
+                create_intf_ep_devs(intf);
         }
 
         usb_autosuspend_device(dev);
         return 0;
 }
 
+static LIST_HEAD(set_config_list);
+static DEFINE_SPINLOCK(set_config_lock);
+
 struct set_config_request {
         struct usb_device       *udev;
         int                     config;
         struct work_struct      work;
+        struct list_head        node;
 };
 
 /* Worker routine for usb_driver_set_configuration() */
@@ -1659,14 +1750,35 @@ static void driver_set_config_work(struct work_struct *work)
 {
         struct set_config_request *req =
                 container_of(work, struct set_config_request, work);
+        struct usb_device *udev = req->udev;
+
+        usb_lock_device(udev);
+        spin_lock(&set_config_lock);
+        list_del(&req->node);
+        spin_unlock(&set_config_lock);
 
-        usb_lock_device(req->udev);
-        usb_set_configuration(req->udev, req->config);
-        usb_unlock_device(req->udev);
-        usb_put_dev(req->udev);
+        if (req->config >= -1)          /* Is req still valid? */
+                usb_set_configuration(udev, req->config);
+        usb_unlock_device(udev);
+        usb_put_dev(udev);
         kfree(req);
 }
 
+/* Cancel pending Set-Config requests for a device whose configuration
+ * was just changed
+ */
+static void cancel_async_set_config(struct usb_device *udev)
+{
+        struct set_config_request *req;
+
+        spin_lock(&set_config_lock);
+        list_for_each_entry(req, &set_config_list, node) {
+                if (req->udev == udev)
+                        req->config = -999;     /* Mark as cancelled */
+        }
+        spin_unlock(&set_config_lock);
+}
+
 /**
  * usb_driver_set_configuration - Provide a way for drivers to change device configurations
  * @udev: the device whose configuration is being updated
@@ -1698,6 +1810,10 @@ int usb_driver_set_configuration(struct usb_device *udev, int config)
         req->config = config;
         INIT_WORK(&req->work, driver_set_config_work);
 
+        spin_lock(&set_config_lock);
+        list_add(&req->node, &set_config_list);
+        spin_unlock(&set_config_lock);
+
         usb_get_dev(udev);
         schedule_work(&req->work);
         return 0;