Eric Callahan f946e6a28d
sysfs_devs: implement mode query
Signed-off-by:  Eric Callahan <arksine.code@gmail.com>
2024-02-03 11:47:23 -05:00

468 lines
17 KiB
Python

# Utilities for enumerating devices using sysfs
#
# Copyright (C) 2024 Eric Callahan <arksine.code@gmail.com>
#
# This file may be distributed under the terms of the GNU GPLv3 license
from __future__ import annotations
import os
import fcntl
import ctypes
import pathlib
import enum
from ..common import ExtendedFlag
from . import ioctl_macros
from typing import (
Dict,
List,
Any,
Union,
Optional
)
DEFAULT_USB_IDS_PATH = "/usr/share/misc/usb.ids"
USB_DEVICE_PATH = "/sys/bus/usb/devices"
TTY_PATH = "/sys/class/tty"
SER_BYPTH_PATH = "/dev/serial/by-path"
SER_BYID_PATH = "/dev/serial/by-id"
V4L_DEVICE_PATH = "/sys/class/video4linux"
V4L_BYPTH_PATH = "/dev/v4l/by-path"
V4L_BYID_PATH = "/dev/v4l/by-id"
OPTIONAL_USB_INFO = ["manufacturer", "product", "serial"]
NULL_DESCRIPTIONS = [
"?", "none", "undefined", "reserved/undefined", "unused", "no subclass"
]
def read_item(parent: pathlib.Path, filename: str) -> str:
return parent.joinpath(filename).read_text().strip()
def find_usb_folder(usb_path: pathlib.Path) -> Optional[str]:
# Find the sysfs usb folder from a child folder
while usb_path.is_dir() and usb_path.name:
dnum_file = usb_path.joinpath("devnum")
bnum_file = usb_path.joinpath("busnum")
if not dnum_file.is_file() or not bnum_file.is_file():
usb_path = usb_path.parent
continue
devnum = int(dnum_file.read_text().strip())
busnum = int(bnum_file.read_text().strip())
return f"{busnum}:{devnum}"
return None
class UsbIdData:
_usb_info_cache: Dict[str, str] = {
"DI:1d50": "OpenMoko, Inc",
"DI:1d50:614e": "Klipper 3d-Printer Firmware",
"DI:1d50:6177": "Katapult Bootloader (CDC_ACM)"
}
def __init__(self, usb_id_path: Union[str, pathlib.Path]) -> None:
if isinstance(usb_id_path, str):
usb_id_path = pathlib.Path(usb_id_path)
self.usb_id_path = usb_id_path.expanduser().resolve()
self.parsed: bool = False
self.usb_info: Dict[str, str] = {}
def _is_hex(self, item: str) -> bool:
try:
int(item, 16)
except ValueError:
return False
return True
def get_item(self, key: str, check_null: bool = False) -> Optional[str]:
item = self.usb_info.get(key, self._usb_info_cache.get(key))
if item is None:
if self.parsed:
return None
self.parse_usb_ids()
item = self.usb_info.get(key)
if item is None:
return None
self._usb_info_cache[key] = item
if check_null and item.lower() in NULL_DESCRIPTIONS:
return None
return item
def parse_usb_ids(self) -> None:
self.parsed = True
if not self.usb_id_path.is_file():
return
top_key: str = ""
sub_key: str = ""
with self.usb_id_path.open(encoding="latin-1") as f:
while True:
line = f.readline()
if not line:
break
stripped_line = line.strip()
if not stripped_line or stripped_line[0] == "#":
continue
if line[:2] == "\t\t":
if not sub_key:
continue
tertiary_id, desc = stripped_line.split(maxsplit=1)
self.usb_info[f"{sub_key}:{tertiary_id.lower()}"] = desc
elif line[0] == "\t":
if not top_key:
continue
sub_id, desc = stripped_line.split(maxsplit=1)
sub_key = f"{top_key}:{sub_id.lower()}"
self.usb_info[sub_key] = desc
else:
id_type, data = line.rstrip().split(maxsplit=1)
if len(id_type) == 4 and self._is_hex(id_type):
# This is a vendor ID
top_key = f"DI:{id_type.lower()}"
self.usb_info[top_key] = data
elif id_type:
# This is a subtype
num_id, desc = data.split(maxsplit=1)
top_key = f"{id_type}:{num_id.lower()}"
self.usb_info[top_key] = desc
else:
break
def get_product_info(self, vendor_id: str, product_id: str) -> Dict[str, Any]:
vendor_name = self.get_item(f"DI:{vendor_id}")
if vendor_name is None:
return {
"description": None,
"manufacturer": None,
"product": None,
}
product_name = self.get_item(f"DI:{vendor_id}:{product_id}")
return {
"description": f"{vendor_name} {product_name or ''}".strip(),
"manufacturer": vendor_name,
"product": product_name,
}
def get_class_info(
self, cls_id: str, subcls_id: str, proto_id: str
) -> Dict[str, Any]:
cls_desc = self.get_item(f"C:{cls_id}")
if cls_desc is None or cls_id == "00":
return {
"class": None,
"subclass": None,
"protocol": None
}
return {
"class": cls_desc,
"subclass": self.get_item(f"C:{cls_id}:{subcls_id}", True),
"protocol": self.get_item(f"C:{cls_id}:{subcls_id}:{proto_id}", True)
}
def find_usb_devices() -> List[Dict[str, Any]]:
dev_folder = pathlib.Path(USB_DEVICE_PATH)
if not dev_folder.is_dir():
return []
usb_devs: List[Dict[str, Any]] = []
# Find sysfs usb device descriptors
for dev_cfg_path in dev_folder.glob("*/bDeviceClass"):
dev_folder = dev_cfg_path.parent
device_info: Dict[str, Any] = {}
try:
device_info["device_num"] = int(read_item(dev_folder, "devnum"))
device_info["bus_num"] = int(read_item(dev_folder, "busnum"))
device_info["vendor_id"] = read_item(dev_folder, "idVendor").lower()
device_info["product_id"] = read_item(dev_folder, "idProduct").lower()
usb_location = f"{device_info['bus_num']}:{device_info['device_num']}"
device_info["usb_location"] = usb_location
dev_cls = read_item(dev_folder, "bDeviceClass").lower()
dev_subcls = read_item(dev_folder, "bDeviceSubClass").lower()
dev_proto = read_item(dev_folder, "bDeviceProtocol").lower()
device_info["class_ids"] = [dev_cls, dev_subcls, dev_proto]
for field in OPTIONAL_USB_INFO:
if dev_folder.joinpath(field).is_file():
device_info[field] = read_item(dev_folder, field)
elif field not in device_info:
device_info[field] = None
except Exception:
continue
usb_devs.append(device_info)
return usb_devs
def find_serial_devices() -> List[Dict[str, Any]]:
serial_devs: List[Dict[str, Any]] = []
devs_by_path: Dict[str, str] = {}
devs_by_id: Dict[str, str] = {}
by_path_dir = pathlib.Path(SER_BYPTH_PATH)
by_id_dir = pathlib.Path(SER_BYID_PATH)
dev_root_folder = pathlib.Path("/dev")
if by_path_dir.is_dir():
devs_by_path = {
dev.resolve().name: str(dev) for dev in by_path_dir.iterdir()
}
if by_id_dir.is_dir():
devs_by_id = {
dev.resolve().name: str(dev) for dev in by_id_dir.iterdir()
}
tty_dir = pathlib.Path(TTY_PATH)
for tty_path in tty_dir.iterdir():
device_folder = tty_path.joinpath("device")
if not device_folder.is_dir():
continue
uartclk_file = tty_path.joinpath("uartclk")
port_file = tty_path.joinpath("port")
device_name = tty_path.name
driver_name = device_folder.joinpath("driver").resolve().name
device_info: Dict[str, Any] = {
"device_type": "unknown",
"device_path": str(dev_root_folder.joinpath(device_name)),
"device_name": device_name,
"driver_name": driver_name,
"path_by_hardware": devs_by_path.get(device_name),
"path_by_id": devs_by_id.get(device_name),
"usb_location": None
}
if uartclk_file.is_file() and port_file.is_file():
# This is a potential hardware uart. Need to
# validate that "serial8250" devices have a port
# number of zero
if driver_name == "serial8250":
portnum = int(port_file.read_text().strip(), 16)
if portnum != 0:
# Not a usable UART
continue
device_info["device_type"] = "hardware_uart"
else:
usb_path = device_folder.resolve()
usb_location: Optional[str] = find_usb_folder(usb_path)
if usb_location is not None:
device_info["device_type"] = "usb"
device_info["usb_location"] = usb_location
serial_devs.append(device_info)
return serial_devs
class struct_v4l2_capability(ctypes.Structure):
_fields_ = [
("driver", ctypes.c_char * 16),
("card", ctypes.c_char * 32),
("bus_info", ctypes.c_char * 32),
("version", ctypes.c_uint32),
("capabilities", ctypes.c_uint32),
("device_caps", ctypes.c_uint32),
("reserved", ctypes.c_uint32 * 3),
]
class struct_v4l2_fmtdesc(ctypes.Structure):
_fields_ = [
("index", ctypes.c_uint32),
("type", ctypes.c_uint32),
("flags", ctypes.c_uint32),
("description", ctypes.c_char * 32),
("pixelformat", ctypes.c_uint32),
("reserved", ctypes.c_uint32 * 4)
]
class struct_v4l2_frmsize_discrete(ctypes.Structure):
_fields_ = [
("width", ctypes.c_uint32),
("height", ctypes.c_uint32),
]
class struct_v4l2_frmsize_stepwise(ctypes.Structure):
_fields_ = [
("min_width", ctypes.c_uint32),
("max_width", ctypes.c_uint32),
("step_width", ctypes.c_uint32),
("min_height", ctypes.c_uint32),
("max_height", ctypes.c_uint32),
("step_height", ctypes.c_uint32),
]
class struct_v4l2_frmsize_union(ctypes.Union):
_fields_ = [
("discrete", struct_v4l2_frmsize_discrete),
("stepwise", struct_v4l2_frmsize_stepwise)
]
class struct_v4l2_frmsizeenum(ctypes.Structure):
_anonymous_ = ("size",)
_fields_ = [
("index", ctypes.c_uint32),
("pixel_format", ctypes.c_uint32),
("type", ctypes.c_uint32),
("size", struct_v4l2_frmsize_union),
("reserved", ctypes.c_uint32 * 2)
]
class V4L2Capability(ExtendedFlag):
VIDEO_CAPTURE = 0x00000001 # noqa: E221
VIDEO_OUTPUT = 0x00000002 # noqa: E221
VIDEO_OVERLAY = 0x00000004 # noqa: E221
VBI_CAPTURE = 0x00000010 # noqa: E221
VBI_OUTPUT = 0x00000020 # noqa: E221
SLICED_VBI_CAPTURE = 0x00000040 # noqa: E221
SLICED_VBI_OUTPUT = 0x00000080 # noqa: E221
RDS_CAPTURE = 0x00000100 # noqa: E221
VIDEO_OUTPUT_OVERLAY = 0x00000200
HW_FREQ_SEEK = 0x00000400 # noqa: E221
RDS_OUTPUT = 0x00000800 # noqa: E221
VIDEO_CAPTURE_MPLANE = 0x00001000
VIDEO_OUTPUT_MPLANE = 0x00002000 # noqa: E221
VIDEO_M2M_MPLANE = 0x00004000 # noqa: E221
VIDEO_M2M = 0x00008000 # noqa: E221
TUNER = 0x00010000 # noqa: E221
AUDIO = 0x00020000 # noqa: E221
RADIO = 0x00040000 # noqa: E221
MODULATOR = 0x00080000 # noqa: E221
SDR_CAPTURE = 0x00100000 # noqa: E221
EXT_PIX_FORMAT = 0x00200000 # noqa: E221
SDR_OUTPUT = 0x00400000 # noqa: E221
META_CAPTURE = 0x00800000 # noqa: E221
READWRITE = 0x01000000 # noqa: E221
STREAMING = 0x04000000 # noqa: E221
META_OUTPUT = 0x08000000 # noqa: E221
TOUCH = 0x10000000 # noqa: E221
IO_MC = 0x20000000 # noqa: E221
SET_DEVICE_CAPS = 0x80000000 # noqa: E221
class V4L2FrameSizeTypes(enum.IntEnum):
DISCRETE = 1
CONTINUOUS = 2
STEPWISE = 3
class V4L2FormatFlags(ExtendedFlag):
COMPRESSED = 0x0001
EMULATED = 0x0002
V4L2_BUF_TYPE_VIDEO_CAPTURE = 1
V4L2_QUERYCAP = ioctl_macros.IOR(ord("V"), 0, struct_v4l2_capability)
V4L2_ENUM_FMT = ioctl_macros.IOWR(ord("V"), 2, struct_v4l2_fmtdesc)
V4L2_ENUM_FRAMESIZES = ioctl_macros.IOWR(ord("V"), 74, struct_v4l2_frmsizeenum)
def v4l2_fourcc_from_fmt(pixelformat: int) -> str:
fmt = bytes([((pixelformat >> (8 * i)) & 0xFF) for i in range(4)])
return fmt.decode(encoding="ascii", errors="ignore")
def v4l2_fourcc(format: str) -> int:
assert len(format) == 4
result: int = 0
for idx, val in enumerate(format.encode()):
result |= (val << (8 * idx)) & 0xFF
return result
def _get_resolutions(fd: int, pixel_format: int) -> List[str]:
res_info = struct_v4l2_frmsizeenum()
result: List[str] = []
for idx in range(128):
res_info.index = idx
res_info.pixel_format = pixel_format
try:
fcntl.ioctl(fd, V4L2_ENUM_FRAMESIZES, res_info)
except OSError:
break
if res_info.type != V4L2FrameSizeTypes.DISCRETE:
break
width = res_info.discrete.width
height = res_info.discrete.height
result.append(f"{width}x{height}")
return result
def _get_modes(fd: int) -> List[Dict[str, Any]]:
pix_info = struct_v4l2_fmtdesc()
result: List[Dict[str, Any]] = []
for idx in range(128):
pix_info.index = idx
pix_info.type = V4L2_BUF_TYPE_VIDEO_CAPTURE
try:
fcntl.ioctl(fd, V4L2_ENUM_FMT, pix_info)
except OSError:
break
desc: str = pix_info.description.decode()
pixel_format: int = pix_info.pixelformat
flags = V4L2FormatFlags(pix_info.flags)
resolutions = _get_resolutions(fd, pixel_format)
if not resolutions:
continue
result.append(
{
"format": v4l2_fourcc_from_fmt(pixel_format),
"description": desc,
"flags": [f.name for f in flags],
"resolutions": resolutions
}
)
return result
def find_video_devices() -> List[Dict[str, Any]]:
v4lpath = pathlib.Path(V4L_DEVICE_PATH)
if not v4lpath.is_dir():
return []
v4l_by_path_dir = pathlib.Path(V4L_BYPTH_PATH)
v4l_by_id_dir = pathlib.Path(V4L_BYID_PATH)
dev_root_folder = pathlib.Path("/dev")
v4l_devs_by_path: Dict[str, str] = {}
v4l_devs_by_id: Dict[str, str] = {}
if v4l_by_path_dir.is_dir():
v4l_devs_by_path = {
dev.resolve().name: str(dev) for dev in v4l_by_path_dir.iterdir()
}
if v4l_by_id_dir.is_dir():
v4l_devs_by_id = {
dev.resolve().name: str(dev) for dev in v4l_by_id_dir.iterdir()
}
v4l_devices: List[Dict[str, Any]] = []
for v4ldev_path in v4lpath.iterdir():
devfs_name = v4ldev_path.name
devfs_path = dev_root_folder.joinpath(devfs_name)
# The video4linux sysfs implmentation provides limited device
# info. Use the VIDEOC_QUERYCAPS ioctl to retreive extended
# information about the v4l2 device.
fd: int = -1
try:
fd = os.open(str(devfs_path), os.O_RDONLY | os.O_NONBLOCK)
cap_info = struct_v4l2_capability()
fcntl.ioctl(fd, V4L2_QUERYCAP, cap_info)
capabilities = V4L2Capability(cap_info.device_caps)
if not capabilities & V4L2Capability.VIDEO_CAPTURE:
# Skip devices that do not capture video
continue
modes = _get_modes(fd)
except Exception:
continue
finally:
if fd != -1:
os.close(fd)
ver_tuple = tuple(
[str((cap_info.version >> (i)) & 0xFF) for i in range(16, -1, -8)]
)
video_device: Dict[str, Any] = {
"device_name": devfs_name,
"device_path": str(devfs_path),
"camera_name": cap_info.card.decode(),
"driver_name": cap_info.driver.decode(),
"hardware_bus": cap_info.bus_info.decode(),
"capabilities": [cap.name for cap in capabilities],
"version": ".".join(ver_tuple),
"path_by_hardware": v4l_devs_by_path.get(devfs_name),
"path_by_id": v4l_devs_by_id.get(devfs_name),
"alt_name": None,
"usb_location": None,
"modes": modes
}
name_file = v4ldev_path.joinpath("name")
if name_file.is_file():
video_device["alt_name"] = read_item(v4ldev_path, "name")
device_path = v4ldev_path.joinpath("device")
if device_path.is_dir():
usb_location = find_usb_folder(device_path.resolve())
if usb_location is not None:
video_device["usb_location"] = usb_location
v4l_devices.append(video_device)
def idx_sorter(item: Dict[str, Any]) -> int:
try:
return int(item["device_name"][5:])
except ValueError:
return -1
# Sort by string first, then index
v4l_devices.sort(key=lambda item: item["device_name"])
v4l_devices.sort(key=idx_sorter)
return v4l_devices