1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
|
# Copyright 2009-2017 Wander Lairson Costa
# Copyright 2009-2021 PyUSB contributors
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# 3. Neither the name of the copyright holder nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
r"""usb.control - USB standard control requests
This module exports:
get_status - get recipeint status
clear_feature - clear a recipient feature
set_feature - set a recipient feature
get_descriptor - get a device descriptor
set_descriptor - set a device descriptor
get_configuration - get a device configuration
set_configuration - set a device configuration
get_interface - get a device interface
set_interface - set a device interface
"""
__author__ = 'Wander Lairson Costa'
__all__ = ['get_status',
'clear_feature',
'set_feature',
'get_descriptor',
'set_descriptor',
'get_configuration',
'set_configuration',
'get_interface',
'set_interface',
'ENDPOINT_HALT',
'FUNCTION_SUSPEND',
'DEVICE_REMOTE_WAKEUP',
'U1_ENABLE',
'U2_ENABLE',
'LTM_ENABLE']
import usb.util as util
import usb.core as core
USBError = core.USBError
def _parse_recipient(recipient, direction):
if recipient is None:
r = util.CTRL_RECIPIENT_DEVICE
wIndex = 0
elif isinstance(recipient, core.Interface):
r = util.CTRL_RECIPIENT_INTERFACE
wIndex = recipient.bInterfaceNumber
elif isinstance(recipient, core.Endpoint):
r = util.CTRL_RECIPIENT_ENDPOINT
wIndex = recipient.bEndpointAddress
else:
raise ValueError('Invalid recipient.')
bmRequestType = util.build_request_type(
direction,
util.CTRL_TYPE_STANDARD,
r
)
return (bmRequestType, wIndex)
# standard feature selectors from USB 2.0/3.0
ENDPOINT_HALT = 0
FUNCTION_SUSPEND = 0
DEVICE_REMOTE_WAKEUP = 1
U1_ENABLE = 48
U2_ENABLE = 49
LTM_ENABLE = 50
def get_status(dev, recipient = None):
r"""Return the status for the specified recipient.
dev is the Device object to which the request will be
sent to.
The recipient can be None (on which the status will be queried
from the device), an Interface or Endpoint descriptors.
The status value is returned as an integer with the lower
word being the two bytes status value.
"""
bmRequestType, wIndex = _parse_recipient(recipient, util.CTRL_IN)
ret = dev.ctrl_transfer(bmRequestType = bmRequestType,
bRequest = 0x00,
wIndex = wIndex,
data_or_wLength = 2)
return ret[0] | (ret[1] << 8)
def clear_feature(dev, feature, recipient = None):
r"""Clear/disable a specific feature.
dev is the Device object to which the request will be
sent to.
feature is the feature you want to disable.
The recipient can be None (on which the status will be queried
from the device), an Interface or Endpoint descriptors.
"""
if feature == ENDPOINT_HALT:
dev.clear_halt(recipient)
else:
bmRequestType, wIndex = _parse_recipient(recipient, util.CTRL_OUT)
dev.ctrl_transfer(bmRequestType = bmRequestType,
bRequest = 0x01,
wIndex = wIndex,
wValue = feature)
def set_feature(dev, feature, recipient = None):
r"""Set/enable a specific feature.
dev is the Device object to which the request will be
sent to.
feature is the feature you want to enable.
The recipient can be None (on which the status will be queried
from the device), an Interface or Endpoint descriptors.
"""
bmRequestType, wIndex = _parse_recipient(recipient, util.CTRL_OUT)
dev.ctrl_transfer(bmRequestType = bmRequestType,
bRequest = 0x03,
wIndex = wIndex,
wValue = feature)
def get_descriptor(dev, desc_size, desc_type, desc_index, wIndex = 0):
r"""Return the specified descriptor.
dev is the Device object to which the request will be
sent to.
desc_size is the descriptor size.
desc_type and desc_index are the descriptor type and index,
respectively. wIndex index is used for string descriptors
and represents the Language ID. For other types of descriptors,
it is zero.
"""
wValue = desc_index | (desc_type << 8)
bmRequestType = util.build_request_type(
util.CTRL_IN,
util.CTRL_TYPE_STANDARD,
util.CTRL_RECIPIENT_DEVICE)
desc = dev.ctrl_transfer(
bmRequestType = bmRequestType,
bRequest = 0x06,
wValue = wValue,
wIndex = wIndex,
data_or_wLength = desc_size)
if len(desc) < 2:
raise USBError('Invalid descriptor')
return desc
def set_descriptor(dev, desc, desc_type, desc_index, wIndex = None):
r"""Update an existing descriptor or add a new one.
dev is the Device object to which the request will be
sent to.
The desc parameter is the descriptor to be sent to the device.
desc_type and desc_index are the descriptor type and index,
respectively. wIndex index is used for string descriptors
and represents the Language ID. For other types of descriptors,
it is zero.
"""
wValue = desc_index | (desc_type << 8)
bmRequestType = util.build_request_type(
util.CTRL_OUT,
util.CTRL_TYPE_STANDARD,
util.CTRL_RECIPIENT_DEVICE)
dev.ctrl_transfer(
bmRequestType = bmRequestType,
bRequest = 0x07,
wValue = wValue,
wIndex = wIndex,
data_or_wLength = desc)
def get_configuration(dev):
r"""Get the current active configuration of the device.
dev is the Device object to which the request will be
sent to.
This function differs from the Device.get_active_configuration
method because the later may use cached data, while this
function always does a device request.
"""
bmRequestType = util.build_request_type(
util.CTRL_IN,
util.CTRL_TYPE_STANDARD,
util.CTRL_RECIPIENT_DEVICE)
return dev.ctrl_transfer(
bmRequestType,
bRequest = 0x08,
data_or_wLength = 1)[0]
def set_configuration(dev, bConfigurationNumber):
r"""Set the current device configuration.
dev is the Device object to which the request will be
sent to.
"""
dev.set_configuration(bConfigurationNumber)
def get_interface(dev, bInterfaceNumber):
r"""Get the current alternate setting of the interface.
dev is the Device object to which the request will be
sent to.
"""
bmRequestType = util.build_request_type(
util.CTRL_IN,
util.CTRL_TYPE_STANDARD,
util.CTRL_RECIPIENT_INTERFACE)
return dev.ctrl_transfer(
bmRequestType = bmRequestType,
bRequest = 0x0a,
wIndex = bInterfaceNumber,
data_or_wLength = 1)[0]
def set_interface(dev, bInterfaceNumber, bAlternateSetting):
r"""Set the alternate setting of the interface.
dev is the Device object to which the request will be
sent to.
"""
dev.set_interface_altsetting(bInterfaceNumber, bAlternateSetting)
|
