Add portio alternative

Author: Steve-Tech

cros_ec_python/devices/lpc.py

@@ -1,5 +1,4 @@
 import struct
-import portio
 import warnings
 import errno
 from ..baseclass import CrosEcClass
@@ -9,6 +8,13 @@
 from ..exceptions import ECError
 
 
+try:
+    import portio
+except ImportError as e:
+    warnings.warn(f"Failed to import portio: {e}, using /dev/port instead.", ImportWarning)
+    from ..utils import devportio as portio
+
+
 class CrosEcLpc(CrosEcClass):
     def __init__(self, init: bool = True, address: Int32 = None):
         self.address = address

cros_ec_python/utils/devportio.py

@@ -0,0 +1,185 @@
+# This file provides a way to interact with the /dev/port device file as an alternative to the portio library.
+# This is a lot slower than the portio library, but it doesn't require an extra package.
+
+def out_bytes(data: bytes, port: int) -> None:
+    """
+    Write data to the specified port.
+    @param data: Data to write.
+    @param port: Port to write to.
+    """
+    with open("/dev/port", "wb") as f:
+        f.seek(port)
+        f.write(data)
+
+
+def outb(data: int, port: int) -> None:
+    """
+    Write a byte to the specified port.
+    @param data: Byte to write.
+    @param port: Port to write to.
+    """
+    out_bytes(data.to_bytes(1, "little"), port)
+
+
+outb_p = outb
+
+
+def outw(data: int, port: int) -> None:
+    """
+    Write a word to the specified port.
+    @param data: Word to write.
+    @param port: Port to write to.
+    """
+    out_bytes(data.to_bytes(2, "little"), port)
+
+
+outw_p = outw
+
+
+def outl(data: int, port: int) -> None:
+    """
+    Write a long to the specified port.
+    @param data: Long to write.
+    @param port: Port to write to.
+    """
+    out_bytes(data.to_bytes(4, "little"), port)
+
+
+outl_p = outl
+
+
+def outsb(data: int, port: int, count: int) -> None:
+    """
+    Write a byte to the specified port, multiple times.
+    @param data: Byte to write.
+    @param port: Port to write to.
+    @param count: Number of times to write.
+    """
+    for i in range(count):
+        outb(data, port)
+
+
+def outsw(data: int, port: int, count: int) -> None:
+    """
+    Write a word to the specified port, multiple times.
+    @param data: Word to write.
+    @param port: Port to write to.
+    @param count: Number of times to write.
+    """
+    for i in range(count):
+        outw(data, port)
+
+
+def outsl(data: int, port: int, count: int) -> None:
+    """
+    Write a long to the specified port, multiple times.
+    @param data: Long to write.
+    @param port: Port to write to.
+    @param count: Number of times to write.
+    """
+    for i in range(count):
+        outl(data, port)
+
+
+def in_bytes(port: int, num: int) -> bytes:
+    """
+    Read data from the specified port.
+    @param port: Port to read from.
+    @param num: Number of bytes to read.
+    @return: Data read.
+    """
+    with open("/dev/port", "rb") as f:
+        f.seek(port)
+        return f.read(num)
+
+
+def inb(port: int) -> int:
+    """
+    Read a byte from the specified port.
+    @param port: Port to read from.
+    @return: Byte read.
+    """
+    return int.from_bytes(in_bytes(port, 1), "little")
+
+
+inb_p = inb
+
+
+def inw(port: int) -> int:
+    """
+    Read a word from the specified port.
+    @param port: Port to read from.
+    @return: Word read.
+    """
+    return int.from_bytes(in_bytes(port, 2), "little")
+
+
+inw_p = inw
+
+
+def inl(port: int) -> int:
+    """
+    Read a long from the specified port.
+    @param port: Port to read from.
+    @return: Long read.
+    """
+    return int.from_bytes(in_bytes(port, 4), "little")
+
+
+inl_p = inl
+
+
+def insb(port: int, data: bytearray, count: int) -> None:
+    """
+    Read a byte from the specified port, multiple times.
+    @param port: Port to read from.
+    @param data: Buffer to read into.
+    @param count: Number of times to read.
+    """
+    for i in range(count):
+        if i >= len(data):
+            data.append(inb(port))
+        else:
+            data[i] = inb(port)
+
+
+def insw(port: int, data: bytearray, count: int) -> None:
+    """
+    Read a word from the specified port, multiple times.
+    @param port: Port to read from.
+    @param data: Buffer to read into.
+    @param count: Number of times to read.
+    """
+    for i in range(count):
+        if i >= len(data):
+            data.append(inw(port))
+        else:
+            data[i] = inw(port)
+
+
+def insl(port: int, data: bytearray, count: int) -> None:
+    """
+    Read a long from the specified port, multiple times.
+    @param port: Port to read from.
+    @param data: Buffer to read into.
+    @param count: Number of times to read.
+    """
+    for i in range(count):
+        if i >= len(data):
+            data.append(inl(port))
+        else:
+            data[i] = inl(port)
+
+
+def ioperm(port: int, num: int, turn_on: bool) -> None:
+    """
+    ioperm stub function. It's not required for /dev/port.
+    """
+    pass
+
+
+def iopl(level: int) -> None:
+    """
+    iopl stub function. It's not required for /dev/port.
+    """
+    pass