Revert "ec-devutils: update pyusb to 1.0.2"

This reverts commit 7d26ae49bffcf269df82df7d0fee00e8c3341166.

pyusb 1.0.2 fails under load and locks up the usb endpoint.

BUG=b:111658037, chromium:865482
TEST=while RES=$(dut-control ec_uart_en spi1_buf_en ); do echo ${RES}; done

CQ-DEPEND=CL:1149509

Original change's description:
> ec-devutils: update pyusb to 1.0.2
>
> Pyusb interface has changed yet again. Patch calls to get_string
> and usb.core.find. Modify ordering of detetch kernel driver
> and avoid rereferencing endpoints.
>
> BRANCH=None
> BUG=b:110907544
> TEST=emerge ec-devutils, run powerlog, usb_console, servo_updater
>
> CQ-DEPEND=CL:1119632
>
> Signed-off-by: Nick Sanders <nsanders@chromium.org>
>
> Change-Id: I33df474ce3bb57d2e11c9f384ac013b51d210843
> Reviewed-on: https://chromium-review.googlesource.com/1125354
> Commit-Ready: Nick Sanders <nsanders@chromium.org>
> Tested-by: Nick Sanders <nsanders@chromium.org>
> Reviewed-by: Aseda Aboagye <aaboagye@chromium.org>

Bug: b:110907544
Change-Id: I04f015b4924e7fee76ab0f1734267e8e2d14faaa
Reviewed-on: https://chromium-review.googlesource.com/1150963
Commit-Ready: Nick Sanders <nsanders@chromium.org>
Tested-by: Nick Sanders <nsanders@chromium.org>
Reviewed-by: Aseda Aboagye <aaboagye@chromium.org>
Reviewed-by: Nick Sanders <nsanders@chromium.org>

5 files changed, 13 insertions, 24 deletions

diff --git a/extra/tigertool/ecusb/stm32uart.py b/extra/tigertool/ecusb/stm32uart.py
index 21fcbd2cc2..459ca8e90f 100644
--- a/extra/tigertool/ecusb/stm32uart.py
+++ b/extra/tigertool/ecusb/stm32uart.py
@@ -73,7 +73,6 @@ class Suart(object):
     if self._tx_thread:
       self._tx_thread.join(2)
       self._tx_thread = None
-    self._susb.close()
 
   def run_rx_thread(self):
     """Background loop to pass data from USB to pty."""
diff --git a/extra/tigertool/ecusb/stm32usb.py b/extra/tigertool/ecusb/stm32usb.py
index 3d3627e8ab..b8ffb2765e 100644
--- a/extra/tigertool/ecusb/stm32usb.py
+++ b/extra/tigertool/ecusb/stm32usb.py
@@ -57,10 +57,8 @@ class Susb(object):
   def _find_device(self):
     """Set up the usb endpoint"""
     # Find the stm32.
-    dev_g = usb.core.find(idVendor=self._vendor, idProduct=self._product,
+    dev_list = usb.core.find(idVendor=self._vendor, idProduct=self._product,
                              find_all=True)
-    dev_list = list(dev_g)
-
     if not dev_list:
       raise SusbError('USB device not found')
 
@@ -68,7 +66,7 @@ class Susb(object):
     dev = None
     if self._serialname:
       for d in dev_list:
-        dev_serial = usb.util.get_string(d, d.iSerialNumber)
+        dev_serial = usb.util.get_string(d, 256, d.iSerialNumber)
         if dev_serial == self._serialname:
           dev = d
           break
@@ -81,20 +79,12 @@ class Susb(object):
         raise SusbError('USB device %04x:%04x not found' % (
             self._vendor, self._product))
 
-    # Detach raiden.ko if it is loaded. CCD endpoints support either a kernel
-    # module driver that produces a ttyUSB, or direct endpoint access, but
-    # can't do both at the same time.
-    if dev.is_kernel_driver_active(self._interface) is True:
-      dev.detach_kernel_driver(self._interface)
-
     # If we can't set configuration, it's already been set.
     try:
       dev.set_configuration()
-    except usb.core.USBError as e:
+    except usb.core.USBError:
       pass
 
-    self._dev = dev
-
     # Get an endpoint instance.
     cfg = dev.get_active_configuration()
     intf = usb.util.find_descriptor(cfg, bInterfaceNumber=self._interface)
@@ -103,6 +93,12 @@ class Susb(object):
       raise SusbError('Interface %04x:%04x - 0x%x not found' % (
           self._vendor, self._product, self._interface))
 
+    # Detach raiden.ko if it is loaded. CCD endpoints support either a kernel
+    # module driver that produces a ttyUSB, or direct endpoint access, but
+    # can't do both at the same time.
+    if dev.is_kernel_driver_active(intf.bInterfaceNumber) is True:
+      dev.detach_kernel_driver(intf.bInterfaceNumber)
+
     read_ep_number = intf.bInterfaceNumber + self.READ_ENDPOINT
     read_ep = usb.util.find_descriptor(intf, bEndpointAddress=read_ep_number)
     self._read_ep = read_ep
@@ -110,6 +106,3 @@ class Susb(object):
     write_ep_number = intf.bInterfaceNumber + self.WRITE_ENDPOINT
     write_ep = usb.util.find_descriptor(intf, bEndpointAddress=write_ep_number)
     self._write_ep = write_ep
-
-  def close(self):
-    usb.util.dispose_resources(self._dev)
diff --git a/extra/usb_power/powerlog.py b/extra/usb_power/powerlog.py
index a8fcae9c9d..82950100f2 100755
--- a/extra/usb_power/powerlog.py
+++ b/extra/usb_power/powerlog.py
@@ -159,8 +159,7 @@ class Spower(object):
     self._board = board
 
     # Find the stm32.
-    dev_g = usb.core.find(idVendor=vendor, idProduct=product, find_all=True)
-    dev_list = list(dev_g)
+    dev_list = usb.core.find(idVendor=vendor, idProduct=product, find_all=True)
     if dev_list is None:
       raise Exception("Power", "USB device not found")
 
diff --git a/extra/usb_serial/console.py b/extra/usb_serial/console.py
index e3288b8593..2494c59c79 100755
--- a/extra/usb_serial/console.py
+++ b/extra/usb_serial/console.py
@@ -71,8 +71,7 @@ class Susb():
       SusbError: An error accessing Susb object
     """
     # Find the device.
-    dev_g = usb.core.find(idVendor=vendor, idProduct=product, find_all=True)
-    dev_list = list(dev_g)
+    dev_list = usb.core.find(idVendor=vendor, idProduct=product, find_all=True)
     if dev_list is None:
       raise SusbError("USB device not found")
 
diff --git a/extra/usb_updater/fw_update.py b/extra/usb_updater/fw_update.py
index 8a73070ccf..367c0cad14 100755
--- a/extra/usb_updater/fw_update.py
+++ b/extra/usb_updater/fw_update.py
@@ -67,8 +67,7 @@ class Supdate(object):
     vendor = self._brdcfg['vid']
     product = self._brdcfg['pid']
 
-    dev_g = usb.core.find(idVendor=vendor, idProduct=product, find_all=True)
-    dev_list = list(dev_g)
+    dev_list = usb.core.find(idVendor=vendor, idProduct=product, find_all=True)
     if dev_list is None:
       raise Exception("Update", "USB device not found")
 
@@ -76,7 +75,7 @@ class Supdate(object):
     dev = None
     if serialname:
       for d in dev_list:
-        if usb.util.get_string(d, d.iSerialNumber) == serialname:
+        if usb.util.get_string(d, 256, d.iSerialNumber) == serialname:
           dev = d
           break
       if dev is None: