diff --git a/tests/test_protect_call.py b/tests/test_protect_call.py
index d10c444..3810e6b 100644
--- a/tests/test_protect_call.py
+++ b/tests/test_protect_call.py
@@ -96,7 +96,10 @@ class TestProtectCall(common.TrezorTest):
         self.client.setup_debuglink(button=True, pin_correct=False)
 
         def test_backoff(attempts, start):
-            expected = 0.2 * (2 ** attempts)
+            if attempts <= 1:
+                expected = 0.2
+            else:
+                expected = (2 ** (attempts - 2))
             got = time.time() - start
 
             msg = "Pin delay expected to be at least %s seconds, got %s" % (expected, got)
diff --git a/trezorctl b/trezorctl
index 29a30c2..ccdabd0 100755
--- a/trezorctl
+++ b/trezorctl
@@ -209,7 +209,7 @@ class Commands(object):
 
     def firmware_update(self, args):
         if args.file:
-            fp = open(args.file, 'r')
+            fp = open(args.file, 'rb').read()
         elif args.url:
             print("Downloading from", args.url)
             r = requests.get(args.url)