USB: usb/dma doc updates

[safe/jmp/linux-2.6] / drivers / usb / core / usb.c

diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 80627b6..0fee5c6 100644 (file)
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -184,10 +184,6 @@ static void usb_release_dev(struct device *dev)
 
        udev = to_usb_device(dev);
 
-#ifdef CONFIG_USB_SUSPEND
-       cancel_delayed_work(&udev->autosuspend);
-       flush_workqueue(ksuspend_usb_wq);
-#endif
        usb_destroy_configuration(udev);
        usb_put_hcd(bus_to_hcd(udev->bus));
        kfree(udev->product);
@@ -257,6 +253,7 @@ usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
        dev->dev.bus = &usb_bus_type;
        dev->dev.type = &usb_device_type;
        dev->dev.dma_mask = bus->controller->dma_mask;
+       set_dev_node(&dev->dev, dev_to_node(bus->controller));
        dev->state = USB_STATE_ATTACHED;
 
        INIT_LIST_HEAD(&dev->ep0.urb_list);
@@ -582,11 +579,12 @@ int __usb_get_extra_descriptor(char *buffer, unsigned size,
  * address (through the pointer provided).
  *
  * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
- * to avoid behaviors like using "DMA bounce buffers", or tying down I/O
- * mapping hardware for long idle periods.  The implementation varies between
+ * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU
+ * hardware during URB completion/resubmit.  The implementation varies between
  * platforms, depending on details of how DMA will work to this device.
- * Using these buffers also helps prevent cacheline sharing problems on
- * architectures where CPU caches are not DMA-coherent.
+ * Using these buffers also eliminates cacheline sharing problems on
+ * architectures where CPU caches are not DMA-coherent.  On systems without
+ * bus-snooping caches, these buffers are uncached.
  *
  * When the buffer is no longer used, free it with usb_buffer_free().
  */
@@ -611,7 +609,7 @@ void *usb_buffer_alloc(
  *
  * This reclaims an I/O buffer, letting it be reused.  The memory must have
  * been allocated using usb_buffer_alloc(), and the parameters must match
- * those provided in that allocation request. 
+ * those provided in that allocation request.
  */
 void usb_buffer_free(
        struct usb_device *dev,