mach_pc/Serial.cc

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "Serial.h"
#include "pedigree/kernel/Log.h"

X86Serial::X86Serial() : m_Port("COM")
{
}

X86Serial::~X86Serial()
{
}

void X86Serial::setBase(uintptr_t nBaseAddr)
{
    m_Port.allocate(nBaseAddr, 8);

    m_Port.write8(0x00, serial::inten);  // Disable all interrupts
    m_Port.write8(0x80, serial::lctrl);  // Enable DLAB (set baud rate divisor)
    m_Port.write8(
        0x01, serial::rxtx);  // Set divisor to 3 (lo byte) 115200 baud
    m_Port.write8(0x00, serial::inten);  //                  (hi byte)
    m_Port.write8(0x03, serial::lctrl);  // 8 bits, no parity, one stop bit
    m_Port.write8(
        0xC7,
        serial::iififo);  // Enable FIFO, clear them, with 14-byte threshold
    m_Port.write8(0x0B, serial::mctrl);  // IRQs enabled, RTS/DSR set
    m_Port.write8(0x0C, serial::inten);  // enable all interrupts.

    NOTICE("Modem status: " << Hex << m_Port.read8(serial::mstat));
    NOTICE("Line status: " << Hex << m_Port.read8(serial::lstat));
}

char X86Serial::read()
{
    if (!isConnected())
        return 0;
    while (!(m_Port.read8(serial::lstat) & 0x1))
        ;

    return m_Port.read8(serial::rxtx);
}

char X86Serial::readNonBlock()
{
    if (!isConnected())
        return 0;
    if (m_Port.read8(serial::lstat) & 0x1)
        return m_Port.read8(serial::rxtx);
    else
        return '\0';
}

void X86Serial::write(char c)
{
    if (!isConnected())
        return;
    while (!(m_Port.read8(serial::lstat) & 0x20))
        ;

    m_Port.write8(static_cast<unsigned char>(c), serial::rxtx);
}

bool X86Serial::isConnected()
{
    return true;
    /*
    uint8_t nStatus = m_Port.read8(serial::mstat);
    // Bits 0x30 = Clear to send & Data set ready.
    // Mstat seems to be 0xFF when the device isn't present.
    if ((nStatus & 0x30) && nStatus != 0xFF)
        return true;
    else
        return false;
    */
}