1 files changed, 62 insertions, 7 deletions

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index adb9c8e..ed83f2b 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1298,6 +1298,7 @@ int usb_set_interface(struct usb_device *dev, int interface, int alternate)
 {
 	struct usb_interface *iface;
 	struct usb_host_interface *alt;
+	struct usb_hcd *hcd = bus_to_hcd(dev->bus);
 	int ret;
 	int manual = 0;
 	unsigned int epaddr;
@@ -1320,6 +1321,18 @@ int usb_set_interface(struct usb_device *dev, int interface, int alternate)
 		return -EINVAL;
 	}
 
+	/* Make sure we have enough bandwidth for this alternate interface.
+	 * Remove the current alt setting and add the new alt setting.
+	 */
+	mutex_lock(&hcd->bandwidth_mutex);
+	ret = usb_hcd_alloc_bandwidth(dev, NULL, iface->cur_altsetting, alt);
+	if (ret < 0) {
+		dev_info(&dev->dev, "Not enough bandwidth for altsetting %d\n",
+				alternate);
+		mutex_unlock(&hcd->bandwidth_mutex);
+		return ret;
+	}
+
 	if (dev->quirks & USB_QUIRK_NO_SET_INTF)
 		ret = -EPIPE;
 	else
@@ -1335,8 +1348,13 @@ int usb_set_interface(struct usb_device *dev, int interface, int alternate)
 			"manual set_interface for iface %d, alt %d\n",
 			interface, alternate);
 		manual = 1;
-	} else if (ret < 0)
+	} else if (ret < 0) {
+		/* Re-instate the old alt setting */
+		usb_hcd_alloc_bandwidth(dev, NULL, alt, iface->cur_altsetting);
+		mutex_unlock(&hcd->bandwidth_mutex);
 		return ret;
+	}
+	mutex_unlock(&hcd->bandwidth_mutex);
 
 	/* FIXME drivers shouldn't need to replicate/bugfix the logic here
 	 * when they implement async or easily-killable versions of this or
@@ -1418,6 +1436,7 @@ int usb_reset_configuration(struct usb_device *dev)
 {
 	int			i, retval;
 	struct usb_host_config	*config;
+	struct usb_hcd *hcd = bus_to_hcd(dev->bus);
 
 	if (dev->state == USB_STATE_SUSPENDED)
 		return -EHOSTUNREACH;
@@ -1433,12 +1452,46 @@ int usb_reset_configuration(struct usb_device *dev)
 	}
 
 	config = dev->actconfig;
+	retval = 0;
+	mutex_lock(&hcd->bandwidth_mutex);
+	/* Make sure we have enough bandwidth for each alternate setting 0 */
+	for (i = 0; i < config->desc.bNumInterfaces; i++) {
+		struct usb_interface *intf = config->interface[i];
+		struct usb_host_interface *alt;
+
+		alt = usb_altnum_to_altsetting(intf, 0);
+		if (!alt)
+			alt = &intf->altsetting[0];
+		if (alt != intf->cur_altsetting)
+			retval = usb_hcd_alloc_bandwidth(dev, NULL,
+					intf->cur_altsetting, alt);
+		if (retval < 0)
+			break;
+	}
+	/* If not, reinstate the old alternate settings */
+	if (retval < 0) {
+reset_old_alts:
+		for (; i >= 0; i--) {
+			struct usb_interface *intf = config->interface[i];
+			struct usb_host_interface *alt;
+
+			alt = usb_altnum_to_altsetting(intf, 0);
+			if (!alt)
+				alt = &intf->altsetting[0];
+			if (alt != intf->cur_altsetting)
+				usb_hcd_alloc_bandwidth(dev, NULL,
+						alt, intf->cur_altsetting);
+		}
+		mutex_unlock(&hcd->bandwidth_mutex);
+		return retval;
+	}
 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 			USB_REQ_SET_CONFIGURATION, 0,
 			config->desc.bConfigurationValue, 0,
 			NULL, 0, USB_CTRL_SET_TIMEOUT);
 	if (retval < 0)
-		return retval;
+		goto reset_old_alts;
+	mutex_unlock(&hcd->bandwidth_mutex);
 
 	/* re-init hc/hcd interface/endpoint state */
 	for (i = 0; i < config->desc.bNumInterfaces; i++) {
@@ -1647,6 +1700,7 @@ int usb_set_configuration(struct usb_device *dev, int configuration)
 	int i, ret;
 	struct usb_host_config *cp = NULL;
 	struct usb_interface **new_interfaces = NULL;
+	struct usb_hcd *hcd = bus_to_hcd(dev->bus);
 	int n, nintf;
 
 	if (dev->authorized == 0 || configuration == -1)
@@ -1716,12 +1770,11 @@ free_interfaces:
 	 * host controller will not allow submissions to dropped endpoints.  If
 	 * this call fails, the device state is unchanged.
 	 */
-	if (cp)
-		ret = usb_hcd_check_bandwidth(dev, cp, NULL);
-	else
-		ret = usb_hcd_check_bandwidth(dev, NULL, NULL);
+	mutex_lock(&hcd->bandwidth_mutex);
+	ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL);
 	if (ret < 0) {
 		usb_autosuspend_device(dev);
+		mutex_unlock(&hcd->bandwidth_mutex);
 		goto free_interfaces;
 	}
 
@@ -1747,10 +1800,12 @@ free_interfaces:
 	dev->actconfig = cp;
 	if (!cp) {
 		usb_set_device_state(dev, USB_STATE_ADDRESS);
-		usb_hcd_check_bandwidth(dev, NULL, NULL);
+		usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
 		usb_autosuspend_device(dev);
+		mutex_unlock(&hcd->bandwidth_mutex);
 		goto free_interfaces;
 	}
+	mutex_unlock(&hcd->bandwidth_mutex);
 	usb_set_device_state(dev, USB_STATE_CONFIGURED);
 
 	/* Initialize the new interface structures and the