uartavr.c

含有完整TCP/IP PPP协议的嵌入式操作系统

/*
 * Copyright (C) 2001-2003 by egnite Software GmbH. All rights reserved.
 *
 * 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 holders nor the names of
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY EGNITE SOFTWARE GMBH 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 EGNITE
 * SOFTWARE GMBH 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.
 *
 * For additional information see http://www.ethernut.de/
 *
 */

/*
 * $Log: uartavr.c,v $
 * Revision 1.3  2005/10/16 23:21:33  hwmaier
 * Fixed compilation issue regards U2X macro with Imagecraft
 *
 * Revision 1.2  2005/10/07 22:01:27  hwmaier
 * Obsolete dcb_baudSelect removed. Support for double speed (U2X) added (using same method as in usartavr.c).
 *
 * Revision 1.1  2005/07/26 18:02:40  haraldkipp
 * Moved from dev.
 *
 * Revision 1.9  2005/07/14 09:12:20  freckle
 * Rewrote CS in UartAvrInput
 *
 * Revision 1.8  2005/01/24 21:12:05  freckle
 * renamed NutEventPostFromIRQ into NutEventPostFromIrq
 *
 * Revision 1.7  2005/01/21 16:49:46  freckle
 * Seperated calls to NutEventPostAsync between Threads and IRQs
 *
 * Revision 1.6  2004/12/16 08:40:35  haraldkipp
 * Late increment fixes ICCAVR bug.
 *
 * Revision 1.5  2004/05/24 20:15:50  drsung
 * Added function UartAvrSize to return number of chars in input buffer.
 *
 * Revision 1.4  2004/03/18 14:01:07  haraldkipp
 * Deprecated header file replaced
 *
 * Revision 1.3  2004/03/18 10:09:27  haraldkipp
 * Removed deprecated raw I/O
 *
 * Revision 1.2  2003/07/20 18:28:10  haraldkipp
 * Explain how to disable timeout.
 *
 * Revision 1.1.1.1  2003/05/09 14:40:55  haraldkipp
 * Initial using 3.2.1
 *
 * Revision 1.21  2003/05/06 18:35:06  harald
 * Avoid duplicate initialization
 *
 * Revision 1.20  2003/04/21 16:26:01  harald
 * Use predefined eof
 *
 * Revision 1.19  2003/03/31 14:53:08  harald
 * Prepare release 3.1
 *
 */

#include <string.h>

#include <sys/atom.h>
#include <sys/heap.h>
#include <sys/event.h>
#include <sys/timer.h>
#include <sys/device.h>

#include <dev/irqreg.h>
#include <dev/uartavr.h>

#include <fcntl.h>

/*
 * Not nice because stdio already defined them. But in order to save memory,
 * we do the whole buffering and including stdio here would be more weird.
 */
#ifndef _IOFBF
#define _IOFBF	    0x00
#define _IOLBF	    0x01
#define _IONBF	    0x02
#endif

/*!
 * \addtogroup xgUartAvr
 */
/*@{*/

/*
 * Handle AVR UART transmit complete.
 */
static void TxComplete(void *arg)
{
    NUTDEVICE *dev = (NUTDEVICE *) arg;
    IFSTREAM *ifs = dev->dev_icb;
    UARTDCB *dcb;

    if (ifs->if_tx_idx != ifs->if_wr_idx) {
#ifdef UDR1
        if (dev->dev_base)
            UDR1 = ifs->if_tx_buf[ifs->if_tx_idx];
        else
#endif
            outp(ifs->if_tx_buf[ifs->if_tx_idx], UDR);
        ifs->if_tx_idx++;
    } else {
        ifs->if_tx_act = 0;
        dcb = dev->dev_dcb;
        NutEventPostFromIrq(&dcb->dcb_tx_rdy);
    }
}

/*
 * Handle AVR UART receive complete.
 *
 * Note, that this function modifies the receive index in
 * interrupt context. This requires, that any non atomic
 * access of this index requires interrupts being disabled.
 * Thanks to Mike Cornelius, who pointed this out.
 */
static void RxComplete(void *arg)
{
    NUTDEVICE *dev = (NUTDEVICE *) arg;
    IFSTREAM *ifs = dev->dev_icb;
    UARTDCB *dcb;

#ifdef UDR1
    if (dev->dev_base)
        ifs->if_rx_buf[ifs->if_rx_idx] = inp(UDR1);
    else
#endif
        ifs->if_rx_buf[ifs->if_rx_idx] = inp(UDR);

    if (ifs->if_rd_idx == ifs->if_rx_idx) {
        dcb = dev->dev_dcb;
        NutEventPostFromIrq(&dcb->dcb_rx_rdy);
    }
    /* Late increment fixes ICCAVR bug on volatile variables. */
    ifs->if_rx_idx++;
}

/*!
 * \brief Wait for input.
 *
 * This function checks the input buffer for any data. If
 * the buffer is empty, the calling \ref xrThread "thread"
 * will be blocked until at least one new character is
 * received or a timeout occurs.
 *
 * \param dev Indicates the UART device.
 *
 * \return 0 on success, -1 on timeout.
 */
int UartAvrInput(NUTDEVICE * dev)
{
    int rc = 0;
    int empty;
    IFSTREAM *ifs = dev->dev_icb;
    UARTDCB *dcb =  dev->dev_dcb;

    NutEnterCritical();
    empty = ifs->if_rd_idx == ifs->if_rx_idx;
    NutExitCritical();

    if (empty) {

        /*
         * Changing if into a while loop fixes a serious bug:
         * Previous receiver events without any waiting thread
         * set the event handle to the signaled state. So the
         * wait returns immediately. Unfortunately the calling
         * routines rely on a filled buffer when we return 0.
         * Thanks to Mike Cornelius, who found this bug.
         *
         * MR (2005-07-14): Reduced critical sections
         */
        do {

            rc = NutEventWait(&dcb->dcb_rx_rdy, dcb->dcb_rtimeout);

            NutEnterCritical();
            empty = ifs->if_rd_idx == ifs->if_rx_idx;
            NutExitCritical();

        } while (rc == 0 && empty);
    }

    return rc;
}

/*!
 * \brief Initiate output.
 *
 * This function checks the output buffer for any data. If
 * the buffer contains at least one character, the transmitter
 * is started, if not already running. The function returns
 * immediately, without waiting for the character being
 * completely transmitted. Any remaining characters in the
 * output buffer are transmitted in the background.
 *
 * \param dev Indicates the UART device.
 *
 * \return 0 on success, -1 otherwise.
 */
int UartAvrOutput(NUTDEVICE * dev)
{
    IFSTREAM *ifs = dev->dev_icb;

    if (ifs->if_tx_act == 0 && ifs->if_tx_idx != ifs->if_wr_idx) {
        ifs->if_tx_act = 1;
#ifdef UDR1
        if (dev->dev_base)
            UDR1 = ifs->if_tx_buf[ifs->if_tx_idx];
        else
#endif
            outp(ifs->if_tx_buf[ifs->if_tx_idx], UDR);
        ifs->if_tx_idx++;
    }
    return 0;
}

/*!
 * \brief Wait for output buffer empty.
 *
 * If the output buffer contains any data, the calling
 * thread is suspended until all data has been transmitted.
 *
 * \param dev Indicates the UART device.
 *
 * \return 0 on success, -1 otherwise.
 */
int UartAvrFlush(NUTDEVICE * dev)
{
    IFSTREAM *ifs = dev->dev_icb;
    UARTDCB *dcb = dev->dev_dcb;

    /*
     * Start any pending output.
     */
    if (UartAvrOutput(dev))
        return -1;

    /*
     * Wait until output buffer empty.
     */
    NutEnterCritical();
    while (ifs->if_tx_idx != ifs->if_wr_idx)
        NutEventWait(&dcb->dcb_tx_rdy, 100);
    NutExitCritical();

    return 0;
}

/*
 *
 * \param dev Indicates the UART device.
 *
 * \return 0 on success, -1 otherwise.
 */
static int UartAvrGetStatus(NUTDEVICE * dev, u_long * status)
{
    IFSTREAM *ifs = dev->dev_icb;
    u_char us;

    *status = 0;

#ifdef UDR1
    if (dev->dev_base)
        us = inp(UCSR1A);
    else
#endif
        us = inp(USR);
    if (us & FE)
        *status |= UART_FRAMINGERROR;
    if (us & DOR)
        *status |= UART_OVERRUNERROR;
    if (ifs->if_tx_idx == ifs->if_wr_idx)
        *status |= UART_TXBUFFEREMPTY;
    if (ifs->if_rd_idx == ifs->if_rx_idx)
        *status |= UART_RXBUFFEREMPTY;
    return 0;
}

/*
 * Carefully enable UART functions.
 */
static void UartAvrEnable(u_short base)
{
    NutEnterCritical();
#ifdef UCSR1B
    if (base)
        UCSR1B = BV(RXCIE) | BV(TXCIE) | BV(RXEN) | BV(TXEN);
    else
#endif
        UCR = BV(RXCIE) | BV(TXCIE) | BV(RXEN) | BV(TXEN);
    NutExitCritical();
}

/*
 * Carefully disable UART functions.
 */
static void UartAvrDisable(u_short base)
{
    /*
     * Disable UART interrupts.
     */
    NutEnterCritical();
#ifdef UCSR1B
    if (base)
        UCSR1B &= ~(BV(RXCIE) | BV(TXCIE));
    else
#endif
        UCR &= ~(BV(RXCIE) | BV(TXCIE));
    NutExitCritical();

    /*
     * Allow incoming or outgoing character to finish.
     */
    NutDelay(10);

    /*
     * Now disable UART functions.
     */
#ifdef UCSR1B
    if (base)
        UCSR1B &= ~(BV(RXEN) | BV(TXEN));
    else
#endif
        UCR &= ~(BV(RXEN) | BV(TXEN));
}

/*!
 * \brief Perform on-chip UART control functions.
 *
 * \param dev  Identifies the device that receives the device-control
 *             function.
 * \param req  Requested control function. May be set to one of the
 *             following constants:
 *             - UART_SETSPEED, conf points to an u_long value containing the baudrate.
 *             - UART_GETSPEED, conf points to an u_long value receiving the current baudrate.
 *             - UART_SETDATABITS, conf points to an u_long value containing the number of data bits, 5, 6, 7 or 8.
 *             - UART_GETDATABITS, conf points to an u_long value receiving the number of data bits, 5, 6, 7 or 8.
 *             - UART_SETPARITY, conf points to an u_long value containing the parity, 0 (no), 1 (odd) or 2 (even).
 *             - UART_GETPARITY, conf points to an u_long value receiving the parity, 0 (no), 1 (odd) or 2 (even).
 *             - UART_SETSTOPBITS, conf points to an u_long value containing the number of stop bits 1 or 2.
 *             - UART_GETSTOPBITS, conf points to an u_long value receiving the number of stop bits 1 or 2.
 *             - UART_SETSTATUS
 *             - UART_GETSTATUS
 *             - UART_SETREADTIMEOUT, conf points to an u_long value containing the read timeout.
 *             - UART_GETREADTIMEOUT, conf points to an u_long value receiving the read timeout.
 *             - UART_SETWRITETIMEOUT, conf points to an u_long value containing the write timeout.
 *             - UART_GETWRITETIMEOUT, conf points to an u_long value receiving the write timeout.
 *             - UART_SETLOCALECHO, conf points to an u_long value containing 0 (off) or 1 (on).
 *             - UART_GETLOCALECHO, conf points to an u_long value receiving 0 (off) or 1 (on).
 *             - UART_SETFLOWCONTROL, conf points to an u_long value containing combined UART_FCTL_ values.
 *             - UART_GETFLOWCONTROL, conf points to an u_long value containing receiving UART_FCTL_ values.
 *             - UART_SETCOOKEDMODE, conf points to an u_long value containing 0 (off) or 1 (on).
 *             - UART_GETCOOKEDMODE, conf points to an u_long value receiving 0 (off) or 1 (on).
 *
 * \param conf Points to a buffer that contains any data required for
 *             the given control function or receives data from that
 *             function.
 * \return 0 on success, -1 otherwise.
 *
 * \warning Timeout values are given in milliseconds and are limited to
 *          the granularity of the system timer. To disable timeout,
 *          set the parameter to NUT_WAIT_INFINITE.
 *
 * \bug For ATmega103, only 8 data bits, 1 stop bit and no parity are allowed.
 *
 */
int UartAvrIOCtl(NUTDEVICE * dev, int req, void *conf)
{
    int rc = 0;
    UARTDCB *dcb;
    u_long *lvp = (u_long *) conf;
    u_long lv = *lvp;
    u_char bv = (u_char) lv;
    u_short sv;
    u_char devnum;

    if (dev == 0)
        dev = &devUart0;

    devnum = dev->dev_base;
    dcb = dev->dev_dcb;

    switch (req) {
    case UART_SETSPEED:
        UartAvrDisable(devnum);
#ifdef __AVR_ENHANCED__
        if (devnum) {
            if (bit_is_set(UCSR1A, U2X1)) {
                lv <<= 2;
            } else {
                lv <<= 3;
            }
        } else {
            if (bit_is_set(UCSR0A, U2X0)) {
                lv <<= 2;
            } else {
                lv <<= 3;
            }
        }
#else
        lv <<= 3;
#endif
        sv = (u_short) ((NutGetCpuClock() / lv + 1UL) / 2UL) - 1;
#ifdef UBRR1H
        if (devnum) {
            UBRR1L = (u_char) sv;
            UBRR1H = (u_char) (sv >> 8);
        } else {
            UBRR0L = (u_char) sv;
            UBRR0H = (u_char) (sv >> 8);
        }