usb: Rename usb_getFrameExp() to usb_get_period()

This is just function renaming - no code implementation changes.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
diff --git a/src/hw/usb-ehci.c b/src/hw/usb-ehci.c
index 6e32e04..2376b1f 100644
--- a/src/hw/usb-ehci.c
+++ b/src/hw/usb-ehci.c
@@ -386,7 +386,7 @@
 {
     struct usb_ehci_s *cntl = container_of(
         usbdev->hub->cntl, struct usb_ehci_s, usb);
-    int frameexp = usb_getFrameExp(usbdev, epdesc);
+    int frameexp = usb_get_period(usbdev, epdesc);
     dprintf(7, "ehci_alloc_intr_pipe %p %d\n", &cntl->usb, frameexp);
 
     if (frameexp > 10)
diff --git a/src/hw/usb-ohci.c b/src/hw/usb-ohci.c
index b9c5d4c..a91e24d 100644
--- a/src/hw/usb-ohci.c
+++ b/src/hw/usb-ohci.c
@@ -328,7 +328,7 @@
 {
     struct usb_ohci_s *cntl = container_of(
         usbdev->hub->cntl, struct usb_ohci_s, usb);
-    int frameexp = usb_getFrameExp(usbdev, epdesc);
+    int frameexp = usb_get_period(usbdev, epdesc);
     dprintf(7, "ohci_alloc_intr_pipe %p %d\n", &cntl->usb, frameexp);
 
     if (frameexp > 5)
diff --git a/src/hw/usb-uhci.c b/src/hw/usb-uhci.c
index bd9e317..a270a82 100644
--- a/src/hw/usb-uhci.c
+++ b/src/hw/usb-uhci.c
@@ -287,7 +287,7 @@
 {
     struct usb_uhci_s *cntl = container_of(
         usbdev->hub->cntl, struct usb_uhci_s, usb);
-    int frameexp = usb_getFrameExp(usbdev, epdesc);
+    int frameexp = usb_get_period(usbdev, epdesc);
     dprintf(7, "uhci_alloc_intr_pipe %p %d\n", &cntl->usb, frameexp);
 
     if (frameexp > 10)
diff --git a/src/hw/usb-xhci.c b/src/hw/usb-xhci.c
index 470cece..0b8ed64 100644
--- a/src/hw/usb-xhci.c
+++ b/src/hw/usb-xhci.c
@@ -1014,7 +1014,7 @@
     in->add = 0x01 | (1 << epid);
     struct xhci_epctx *ep = (void*)&in[(pipe->epid+1) << xhci->context64];
     if (eptype == USB_ENDPOINT_XFER_INT)
-        ep->ctx[0] = (usb_getFrameExp(usbdev, epdesc) + 3) << 16;
+        ep->ctx[0] = (usb_get_period(usbdev, epdesc) + 3) << 16;
     ep->ctx[1]   |= eptype << 3;
     if (epdesc->bEndpointAddress & USB_DIR_IN
         || eptype == USB_ENDPOINT_XFER_CONTROL)
diff --git a/src/hw/usb.c b/src/hw/usb.c
index f870481..720e8b0 100644
--- a/src/hw/usb.c
+++ b/src/hw/usb.c
@@ -178,8 +178,8 @@
 
 // Find the exponential period of the requested interrupt end point.
 int
-usb_getFrameExp(struct usbdevice_s *usbdev
-                , struct usb_endpoint_descriptor *epdesc)
+usb_get_period(struct usbdevice_s *usbdev
+               , struct usb_endpoint_descriptor *epdesc)
 {
     int period = epdesc->bInterval;
     if (usbdev->speed != USB_HIGHSPEED)
diff --git a/src/hw/usb.h b/src/hw/usb.h
index fe80ea6..0d07032 100644
--- a/src/hw/usb.h
+++ b/src/hw/usb.h
@@ -239,8 +239,8 @@
 struct usb_pipe *usb_getFreePipe(struct usb_s *cntl, u8 eptype);
 void usb_desc2pipe(struct usb_pipe *pipe, struct usbdevice_s *usbdev
                    , struct usb_endpoint_descriptor *epdesc);
-int usb_getFrameExp(struct usbdevice_s *usbdev
-                    , struct usb_endpoint_descriptor *epdesc);
+int usb_get_period(struct usbdevice_s *usbdev
+                   , struct usb_endpoint_descriptor *epdesc);
 int usb_xfer_time(struct usb_pipe *pipe, int datalen);
 struct usb_endpoint_descriptor *findEndPointDesc(struct usbdevice_s *usbdev
                                                  , int type, int dir);