From 34052af9db71e5be46f23f812505a6f844e0b88e Mon Sep 17 00:00:00 2001
From: matejcik <ja@matejcik.cz>
Date: Fri, 5 Apr 2019 17:15:55 +0200
Subject: [PATCH] trezorctl: add USB reset command for stuck devices

---
 trezorctl                     | 12 ++++++++++++
 trezorlib/transport/webusb.py |  7 ++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/trezorctl b/trezorctl
index a447252ba..87b691133 100755
--- a/trezorctl
+++ b/trezorctl
@@ -774,6 +774,18 @@ def self_test(connect):
     return debuglink.self_test(connect())
 
 
+@cli.command()
+def usb_reset():
+    """Perform USB reset on a stuck device.
+
+    This can fix LIBUSB_ERROR_PIPE and similar errors when connecting to a device
+    in a messed state.
+    """
+    from trezorlib.transport.webusb import WebUsbTransport
+
+    WebUsbTransport.enumerate(usb_reset=True)
+
+
 #
 # Basic coin functions
 #
diff --git a/trezorlib/transport/webusb.py b/trezorlib/transport/webusb.py
index a4c2840ee..1b168c3df 100644
--- a/trezorlib/transport/webusb.py
+++ b/trezorlib/transport/webusb.py
@@ -106,7 +106,7 @@ class WebUsbTransport(ProtocolBasedTransport):
         return "%s:%s" % (self.PATH_PREFIX, dev_to_str(self.device))
 
     @classmethod
-    def enumerate(cls) -> Iterable["WebUsbTransport"]:
+    def enumerate(cls, usb_reset=False) -> Iterable["WebUsbTransport"]:
         if cls.context is None:
             cls.context = usb1.USBContext()
             cls.context.open()
@@ -128,6 +128,11 @@ class WebUsbTransport(ProtocolBasedTransport):
                 devices.append(WebUsbTransport(dev))
             except usb1.USBErrorNotSupported:
                 pass
+            except usb1.USBErrorPipe:
+                if usb_reset:
+                    handle = dev.open()
+                    handle.resetDevice()
+                    handle.close()
         return devices
 
     def find_debug(self) -> "WebUsbTransport":