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| 1 | +# MicroPython USB host library, compatible with PyUSB. |
| 2 | +# MIT license; Copyright (c) 2021-2024 Damien P. George |
| 3 | + |
| 4 | +import sys |
| 5 | +import ffi |
| 6 | +import uctypes |
| 7 | + |
| 8 | +if sys.maxsize >> 32: |
| 9 | + UINTPTR_SIZE = 8 |
| 10 | + UINTPTR = uctypes.UINT64 |
| 11 | +else: |
| 12 | + UINTPTR_SIZE = 4 |
| 13 | + UINTPTR = uctypes.UINT32 |
| 14 | + |
| 15 | + |
| 16 | +def _align_word(x): |
| 17 | + return (x + UINTPTR_SIZE - 1) & ~(UINTPTR_SIZE - 1) |
| 18 | + |
| 19 | + |
| 20 | +ptr_descriptor = (0 | uctypes.ARRAY, 1 | UINTPTR) |
| 21 | + |
| 22 | +libusb_device_descriptor = { |
| 23 | + "bLength": 0 | uctypes.UINT8, |
| 24 | + "bDescriptorType": 1 | uctypes.UINT8, |
| 25 | + "bcdUSB": 2 | uctypes.UINT16, |
| 26 | + "bDeviceClass": 4 | uctypes.UINT8, |
| 27 | + "bDeviceSubClass": 5 | uctypes.UINT8, |
| 28 | + "bDeviceProtocol": 6 | uctypes.UINT8, |
| 29 | + "bMaxPacketSize0": 7 | uctypes.UINT8, |
| 30 | + "idVendor": 8 | uctypes.UINT16, |
| 31 | + "idProduct": 10 | uctypes.UINT16, |
| 32 | + "bcdDevice": 12 | uctypes.UINT16, |
| 33 | + "iManufacturer": 14 | uctypes.UINT8, |
| 34 | + "iProduct": 15 | uctypes.UINT8, |
| 35 | + "iSerialNumber": 16 | uctypes.UINT8, |
| 36 | + "bNumConfigurations": 17 | uctypes.UINT8, |
| 37 | +} |
| 38 | + |
| 39 | +libusb_config_descriptor = { |
| 40 | + "bLength": 0 | uctypes.UINT8, |
| 41 | + "bDescriptorType": 1 | uctypes.UINT8, |
| 42 | + "wTotalLength": 2 | uctypes.UINT16, |
| 43 | + "bNumInterfaces": 4 | uctypes.UINT8, |
| 44 | + "bConfigurationValue": 5 | uctypes.UINT8, |
| 45 | + "iConfiguration": 6 | uctypes.UINT8, |
| 46 | + "bmAttributes": 7 | uctypes.UINT8, |
| 47 | + "MaxPower": 8 | uctypes.UINT8, |
| 48 | + "interface": _align_word(9) | UINTPTR, # array of libusb_interface |
| 49 | + "extra": (_align_word(9) + UINTPTR_SIZE) | UINTPTR, |
| 50 | + "extra_length": (_align_word(9) + 2 * UINTPTR_SIZE) | uctypes.INT, |
| 51 | +} |
| 52 | + |
| 53 | +libusb_interface = { |
| 54 | + "altsetting": 0 | UINTPTR, # array of libusb_interface_descriptor |
| 55 | + "num_altsetting": UINTPTR_SIZE | uctypes.INT, |
| 56 | +} |
| 57 | + |
| 58 | +libusb_interface_descriptor = { |
| 59 | + "bLength": 0 | uctypes.UINT8, |
| 60 | + "bDescriptorType": 1 | uctypes.UINT8, |
| 61 | + "bInterfaceNumber": 2 | uctypes.UINT8, |
| 62 | + "bAlternateSetting": 3 | uctypes.UINT8, |
| 63 | + "bNumEndpoints": 4 | uctypes.UINT8, |
| 64 | + "bInterfaceClass": 5 | uctypes.UINT8, |
| 65 | + "bInterfaceSubClass": 6 | uctypes.UINT8, |
| 66 | + "bInterfaceProtocol": 7 | uctypes.UINT8, |
| 67 | + "iInterface": 8 | uctypes.UINT8, |
| 68 | + "endpoint": _align_word(9) | UINTPTR, |
| 69 | + "extra": (_align_word(9) + UINTPTR_SIZE) | UINTPTR, |
| 70 | + "extra_length": (_align_word(9) + 2 * UINTPTR_SIZE) | uctypes.INT, |
| 71 | +} |
| 72 | + |
| 73 | +libusb = ffi.open("libusb-1.0.so") |
| 74 | +libusb_init = libusb.func("i", "libusb_init", "p") |
| 75 | +libusb_exit = libusb.func("v", "libusb_exit", "p") |
| 76 | +libusb_get_device_list = libusb.func("i", "libusb_get_device_list", "pp") # return is ssize_t |
| 77 | +libusb_free_device_list = libusb.func("v", "libusb_free_device_list", "pi") |
| 78 | +libusb_get_device_descriptor = libusb.func("i", "libusb_get_device_descriptor", "pp") |
| 79 | +libusb_get_config_descriptor = libusb.func("i", "libusb_get_config_descriptor", "pBp") |
| 80 | +libusb_free_config_descriptor = libusb.func("v", "libusb_free_config_descriptor", "p") |
| 81 | +libusb_open = libusb.func("i", "libusb_open", "pp") |
| 82 | +libusb_set_configuration = libusb.func("i", "libusb_set_configuration", "pi") |
| 83 | +libusb_claim_interface = libusb.func("i", "libusb_claim_interface", "pi") |
| 84 | +libusb_control_transfer = libusb.func("i", "libusb_control_transfer", "pBBHHpHI") |
| 85 | + |
| 86 | + |
| 87 | +def _new(sdesc): |
| 88 | + buf = bytearray(uctypes.sizeof(sdesc)) |
| 89 | + s = uctypes.struct(uctypes.addressof(buf), sdesc) |
| 90 | + return s |
| 91 | + |
| 92 | + |
| 93 | +class Interface: |
| 94 | + def __init__(self, descr): |
| 95 | + # Public attributes. |
| 96 | + self.bInterfaceClass = descr.bInterfaceClass |
| 97 | + self.bInterfaceSubClass = descr.bInterfaceSubClass |
| 98 | + self.iInterface = descr.iInterface |
| 99 | + self.extra_descriptors = uctypes.bytes_at(descr.extra, descr.extra_length) |
| 100 | + |
| 101 | + |
| 102 | +class Configuration: |
| 103 | + def __init__(self, dev, cfg_idx): |
| 104 | + cfgs = _new(ptr_descriptor) |
| 105 | + if libusb_get_config_descriptor(dev._dev, cfg_idx, cfgs) != 0: |
| 106 | + libusb_exit(0) |
| 107 | + raise Exception |
| 108 | + descr = uctypes.struct(cfgs[0], libusb_config_descriptor) |
| 109 | + |
| 110 | + # Extract all needed info because descr is going to be free'd at the end. |
| 111 | + self._itfs = [] |
| 112 | + itf_array = uctypes.struct( |
| 113 | + descr.interface, (0 | uctypes.ARRAY, descr.bNumInterfaces, libusb_interface) |
| 114 | + ) |
| 115 | + for i in range(descr.bNumInterfaces): |
| 116 | + itf = itf_array[i] |
| 117 | + alt_array = uctypes.struct( |
| 118 | + itf.altsetting, |
| 119 | + (0 | uctypes.ARRAY, itf.num_altsetting, libusb_interface_descriptor), |
| 120 | + ) |
| 121 | + for j in range(itf.num_altsetting): |
| 122 | + alt = alt_array[j] |
| 123 | + self._itfs.append(Interface(alt)) |
| 124 | + |
| 125 | + # Public attributes. |
| 126 | + self.bNumInterfaces = descr.bNumInterfaces |
| 127 | + self.bConfigurationValue = descr.bConfigurationValue |
| 128 | + self.bmAttributes = descr.bmAttributes |
| 129 | + self.bMaxPower = descr.MaxPower |
| 130 | + self.extra_descriptors = uctypes.bytes_at(descr.extra, descr.extra_length) |
| 131 | + |
| 132 | + # Free descr memory in the driver. |
| 133 | + libusb_free_config_descriptor(cfgs[0]) |
| 134 | + |
| 135 | + def __iter__(self): |
| 136 | + return iter(self._itfs) |
| 137 | + |
| 138 | + |
| 139 | +class Device: |
| 140 | + _TIMEOUT_DEFAULT = 1000 |
| 141 | + |
| 142 | + def __init__(self, dev, descr): |
| 143 | + self._dev = dev |
| 144 | + self._num_cfg = descr.bNumConfigurations |
| 145 | + self._handle = None |
| 146 | + self._claim_itf = set() |
| 147 | + |
| 148 | + # Public attributes. |
| 149 | + self.idVendor = descr.idVendor |
| 150 | + self.idProduct = descr.idProduct |
| 151 | + |
| 152 | + def __iter__(self): |
| 153 | + for i in range(self._num_cfg): |
| 154 | + yield Configuration(self, i) |
| 155 | + |
| 156 | + def __getitem__(self, i): |
| 157 | + return Configuration(self, i) |
| 158 | + |
| 159 | + def _open(self): |
| 160 | + if self._handle is None: |
| 161 | + # Open the USB device. |
| 162 | + handle = _new(ptr_descriptor) |
| 163 | + if libusb_open(self._dev, handle) != 0: |
| 164 | + libusb_exit(0) |
| 165 | + raise Exception |
| 166 | + self._handle = handle[0] |
| 167 | + |
| 168 | + def _claim_interface(self, i): |
| 169 | + if libusb_claim_interface(self._handle, i) != 0: |
| 170 | + libusb_exit(0) |
| 171 | + raise Exception |
| 172 | + |
| 173 | + def set_configuration(self): |
| 174 | + # Select default configuration. |
| 175 | + self._open() |
| 176 | + cfg = Configuration(self, 0).bConfigurationValue |
| 177 | + ret = libusb_set_configuration(self._handle, cfg) |
| 178 | + if ret != 0: |
| 179 | + libusb_exit(0) |
| 180 | + raise Exception |
| 181 | + |
| 182 | + def ctrl_transfer( |
| 183 | + self, bmRequestType, bRequest, wValue=0, wIndex=0, data_or_wLength=None, timeout=None |
| 184 | + ): |
| 185 | + if data_or_wLength is None: |
| 186 | + l = 0 |
| 187 | + data = bytes() |
| 188 | + elif isinstance(data_or_wLength, int): |
| 189 | + l = data_or_wLength |
| 190 | + data = bytearray(l) |
| 191 | + else: |
| 192 | + l = len(data_or_wLength) |
| 193 | + data = data_or_wLength |
| 194 | + self._open() |
| 195 | + if wIndex & 0xFF not in self._claim_itf: |
| 196 | + self._claim_interface(wIndex & 0xFF) |
| 197 | + self._claim_itf.add(wIndex & 0xFF) |
| 198 | + if timeout is None: |
| 199 | + timeout = self._TIMEOUT_DEFAULT |
| 200 | + ret = libusb_control_transfer( |
| 201 | + self._handle, bmRequestType, bRequest, wValue, wIndex, data, l, timeout * 1000 |
| 202 | + ) |
| 203 | + if ret < 0: |
| 204 | + libusb_exit(0) |
| 205 | + raise Exception |
| 206 | + if isinstance(data_or_wLength, int): |
| 207 | + return data |
| 208 | + else: |
| 209 | + return ret |
| 210 | + |
| 211 | + |
| 212 | +def find(*, find_all=False, custom_match=None, idVendor=None, idProduct=None): |
| 213 | + if libusb_init(0) < 0: |
| 214 | + raise Exception |
| 215 | + |
| 216 | + devs = _new(ptr_descriptor) |
| 217 | + count = libusb_get_device_list(0, devs) |
| 218 | + if count < 0: |
| 219 | + libusb_exit(0) |
| 220 | + raise Exception |
| 221 | + |
| 222 | + dev_array = uctypes.struct(devs[0], (0 | uctypes.ARRAY, count | UINTPTR)) |
| 223 | + descr = _new(libusb_device_descriptor) |
| 224 | + devices = None |
| 225 | + for i in range(count): |
| 226 | + libusb_get_device_descriptor(dev_array[i], descr) |
| 227 | + if idVendor and descr.idVendor != idVendor: |
| 228 | + continue |
| 229 | + if idProduct and descr.idProduct != idProduct: |
| 230 | + continue |
| 231 | + device = Device(dev_array[i], descr) |
| 232 | + if custom_match and not custom_match(device): |
| 233 | + continue |
| 234 | + if not find_all: |
| 235 | + return device |
| 236 | + if not devices: |
| 237 | + devices = [] |
| 238 | + devices.append(device) |
| 239 | + return devices |
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