USB: add ep->enable

This patch (as944) adds an explicit "enabled" field to the
usb_host_endpoint structure and uses it in place of the current
mechanism.  This is merely a time-space tradeoff; it makes checking
whether URBs may be submitted to an endpoint simpler.  The existing
mechanism is efficient when converting urb->pipe to an endpoint
pointer, but it's not so efficient when urb->ep is used instead.

As a side effect, the procedure for enabling an endpoint is now a
little more complicated.  The ad-hoc inline code in usb.c and hub.c
for enabling ep0 is now replaced with calls to usb_enable_endpoint,
which is no longer static.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

5 files changed, 15 insertions, 16 deletions

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index fb82c500caf4..cc5b1d3c3680 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -943,7 +943,6 @@ int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
 {
         int                     status;
         struct usb_hcd          *hcd = bus_to_hcd(urb->dev->bus);
-        struct usb_host_endpoint *ep;
         unsigned long           flags;
 
         if (!hcd)
@@ -960,9 +959,7 @@ int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
         // FIXME:  verify that quiescing hc works right (RH cleans up)
 
         spin_lock_irqsave(&hcd_urb_list_lock, flags);
-        ep = (usb_pipein(urb->pipe) ? urb->dev->ep_in : urb->dev->ep_out)
-                        [usb_pipeendpoint(urb->pipe)];
-        if (unlikely(ep != urb->ep))
+        if (unlikely(!urb->ep->enabled))
                 status = -ENOENT;
         else if (unlikely (urb->reject))
                 status = -EPERM;
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index f7b337feb3ea..c8a01f66df70 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1999,7 +1999,7 @@ static void ep0_reinit(struct usb_device *udev)
 {
         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
-        udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
+        usb_enable_endpoint(udev, &udev->ep0);
 }
 
 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index d8f7b089a8f0..0d618647758e 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1013,8 +1013,10 @@ void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr)
                 ep = dev->ep_in[epnum];
                 dev->ep_in[epnum] = NULL;
         }
-        if (ep && dev->bus)
+        if (ep) {
+                ep->enabled = 0;
                 usb_hcd_endpoint_disable(dev, ep);
+        }
 }
 
 /**
@@ -1096,23 +1098,21 @@ void usb_disable_device(struct usb_device *dev, int skip_ep0)
  * Resets the endpoint toggle, and sets dev->ep_{in,out} pointers.
  * For control endpoints, both the input and output sides are handled.
  */
-static 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)
 {
-        unsigned int epaddr = ep->desc.bEndpointAddress;
-        unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
-        int is_control;
+        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);
 
-        is_control = ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
-                        == USB_ENDPOINT_XFER_CONTROL);
-        if (usb_endpoint_out(epaddr) || is_control) {
+        if (is_out || is_control) {
                 usb_settoggle(dev, epnum, 1, 0);
                 dev->ep_out[epnum] = ep;
         }
-        if (!usb_endpoint_out(epaddr) || is_control) {
+        if (!is_out || is_control) {
                 usb_settoggle(dev, epnum, 0, 0);
                 dev->ep_in[epnum] = ep;
         }
+        ep->enabled = 1;
 }
 
 /*
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 0fee5c66fd64..d3c68d8eafb2 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -260,7 +260,7 @@ usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
         dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
         dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
         /* ep0 maxpacket comes later, from device descriptor */
-        dev->ep_in[0] = dev->ep_out[0] = &dev->ep0;
+        usb_enable_endpoint(dev, &dev->ep0);
 
         /* Save readable and stable topology id, distinguishing devices
          * by location for diagnostics, tools, driver model, etc.  The
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index ad5fa0338f49..cde6e52b84fe 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -8,6 +8,8 @@ extern int usb_create_ep_files(struct device *parent, struct usb_host_endpoint *
                                 struct usb_device *udev);
 extern void usb_remove_ep_files(struct usb_host_endpoint *endpoint);
 
+extern void usb_enable_endpoint(struct usb_device *dev,
+                struct usb_host_endpoint *ep);
 extern void usb_disable_endpoint (struct usb_device *dev, unsigned int epaddr);
 extern void usb_disable_interface (struct usb_device *dev,
                 struct usb_interface *intf);