Add function matching endpoint with ep descriptor. This function checks if
hardware endponit can fulfill requirements requested in descriptor. This
function can be used by UDC drivers in match_ep() callback to avoid writing
lots of repetitive code.

Signed-off-by: Robert Baldyga <r.bald...@samsung.com>
---
 drivers/usb/gadget/udc/udc-core.c | 69 +++++++++++++++++++++++++++++++++++++++
 include/linux/usb/gadget.h        |  8 +++++
 2 files changed, 77 insertions(+)

diff --git a/drivers/usb/gadget/udc/udc-core.c 
b/drivers/usb/gadget/udc/udc-core.c
index d69c355..2dff8df 100644
--- a/drivers/usb/gadget/udc/udc-core.c
+++ b/drivers/usb/gadget/udc/udc-core.c
@@ -129,6 +129,75 @@ EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
 
 /* ------------------------------------------------------------------------- */
 
+int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
+               struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
+               struct usb_ss_ep_comp_descriptor *ep_comp)
+{
+       u8              type;
+       u16             max;
+       int             num_req_streams = 0;
+
+       /* endpoint already claimed? */
+       if (ep->claimed)
+               return 0;
+
+       type = usb_endpoint_type(desc);
+       max = 0x7ff & usb_endpoint_maxp(desc);
+
+       if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
+               return 0;
+       else if (!ep->caps.dir_out)
+               return 0;
+
+       if (max > ep->maxpacket_limit)
+               return 0;
+
+       /* "high bandwidth" works only at high speed */
+       if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp(desc) & (3<<11))
+               return 0;
+
+       switch (type) {
+       case USB_ENDPOINT_XFER_CONTROL:
+               /* only support ep0 for portable CONTROL traffic */
+               return 0;
+       case USB_ENDPOINT_XFER_ISOC:
+               if (!ep->caps.type_iso)
+                       return 0;
+               /* ISO:  limit 1023 bytes full speed, 1024 high/super speed */
+               if (!gadget_is_dualspeed(gadget) && max > 1023)
+                       return 0;
+               break;
+       case USB_ENDPOINT_XFER_BULK:
+               if (!ep->caps.type_bulk)
+                       return 0;
+               if (ep_comp && gadget_is_superspeed(gadget)) {
+                       /* Get the number of required streams from the
+                        * EP companion descriptor and see if the EP
+                        * matches it
+                        */
+                       num_req_streams = ep_comp->bmAttributes & 0x1f;
+                       if (num_req_streams > ep->max_streams)
+                               return 0;
+               }
+               break;
+       case USB_ENDPOINT_XFER_INT:
+               /* Bulk endpoints handle interrupt transfers,
+                * except the toggle-quirky iso-synch kind
+                */
+               if (!ep->caps.type_int && !ep->caps.type_bulk)
+                       return 0;
+               /* INT:  limit 64 bytes full speed, 1024 high/super speed */
+               if (!gadget_is_dualspeed(gadget) && max > 64)
+                       return 0;
+               break;
+       }
+
+       return 1;
+}
+EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
+
+/* ------------------------------------------------------------------------- */
+
 static void usb_gadget_state_work(struct work_struct *work)
 {
        struct usb_gadget *gadget = work_to_gadget(work);
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 0041bb9..77e2c1e 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -1079,6 +1079,14 @@ extern void usb_gadget_giveback_request(struct usb_ep 
*ep,
 
 /*-------------------------------------------------------------------------*/
 
+/* utility to check if endpoint caps match descriptor needs */
+
+extern int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
+               struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
+               struct usb_ss_ep_comp_descriptor *ep_comp);
+
+/*-------------------------------------------------------------------------*/
+
 /* utility to update vbus status for udc core, it may be scheduled */
 extern void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status);
 
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to