Add modify method for ADDR.

1 files changed, 12 insertions, 2 deletions

diff --git a/usbh/src/pipe/addr.rs b/usbh/src/pipe/addr.rs
index 8b92177..3ff2d2d 100644
--- a/usbh/src/pipe/addr.rs
+++ b/usbh/src/pipe/addr.rs
@@ -27,8 +27,16 @@ impl Addr {
     {
         let mut w = W { bits: self.0 };
         f(&mut w);
-        // Address must be 32-bit aligned.
-        assert!((w.bits & 0x3) == 0);
+        self.0 = w.bits;
+    }
+
+    pub fn modify<F>(&mut self, f: F)
+    where
+        for<'w> F: FnOnce(&R, &'w mut W) -> &'w mut W,
+    {
+        let r = R { bits: self.0 };
+        let mut w = W { bits: self.0 };
+        f(&r, &mut w);
         self.0 = w.bits;
     }
 }
@@ -79,6 +87,8 @@ pub(crate) struct AddrW<'a> {
 }
 impl<'a> AddrW<'a> {
     pub unsafe fn bits(self, v: u32) -> &'a mut W {
+        // Address must be 32-bit aligned.
+        assert!((v & 0x3) == 0);
         self.w.bits = v;
         self.w
     }