pio.c

来自「《嵌入式固件开发》一书的源码」· C语言 代码 · 共 272 行

/* pio.c:
    Support the basic ability to configure and set/clear parallel IO pins.

    General notice:
    This code is part of a boot-monitor package developed as a generic base
    platform for embedded system designs.  As such, it is likely to be
    distributed to various projects beyond the control of the original
    author.  Please notify the author of any enhancements made or bugs found
    so that all may benefit from the changes.  In addition, notification back
    to the author will allow the new user to pick up changes that may have
    been made by other users after this version of the code was distributed.

    Author: Ed Sutter
    email:  [e-mail]      (home: [e-mail])
    phone:  [phone]            (home: 908-889-5161)
*/
#include "config.h"
#include "cpuio.h"
#include "ctype.h"
#include "genlib.h"
#include "stddefs.h"

#define PIO_IN  1
#define PIO_OUT 2
#define PIO_GP  3
#define PIO_DED 4

/* Pio():
    Display/Configure/Modify 68307 PIO pins.
    Syntax
    pio [options] {A|B} {bit #} [0|1]

      For port A, bit # range = 0-7
      For port B, bit # range = 0-15
      Options:
        -i  configure as in
        -o  configure as out
        -g  configure as gpio
        -d  configure as dedicated
*/

#if INCLUDE_PIO

char *PioHelp[] = {
    "Programmable IO Interface",
    "-[iogdw] {A|B} {bit #} [0|1]",
    " -i   input",
    " -o   output",
    " -g   gpio",
    " -d   dedicated",
    " -w   waitonbit",
    0,
};

void pioshow(void);

int
Pio(int argc,char *argv[])
{
    int opt, bitnum, val, config, portAorB, waitonbit;

    if (argc == 1) {
        pioshow();
        return(0);
    }

    config = 0;
    waitonbit = 0;
    while((opt=getopt(argc,argv,"iogdw")) != -1) {
        switch(opt) {
        case 'o':
            config = PIO_OUT;
            break;
        case 'g':
            config = PIO_GP;
            break;
        case 'd':
            config = PIO_DED;
            break;
        case 'i':
            config = PIO_IN;
            break;
        case 'w':
            waitonbit = 1;
            break;
        default:
            return(0);
        }
    }

    if (argc < (optind+2))
        return(-1);

    portAorB = tolower(argv[optind][0]);
    bitnum = (int)strtol(argv[optind+1],(char **)0,0);

    if (portAorB == 'a') {
        if (bitnum > 15)  {
            printf("Bit # out of range\n");
            return(0);
        }
    }
    else if (portAorB == 'b') {
        if (bitnum > 11) {
            printf("Bit # out of range\n");
            return(0);
        }
    }
    else
        return(-1);

    if (waitonbit) {
        if (argc != (optind+3)) {
            printf("-w requires port, bit and value\n");
            return(-1);
        }
        val = argv[optind+2][0] & 1;
        if (portAorB == 'a') {
            while(1) {
                if ((val == 1) &&
                    (*(ushort *)PADAT&(ushort)~(0x01<<bitnum)))
                    break;
                else if ((val == 0) &&
                    !(*(ushort *)PADAT&(ushort)~(0x01<<bitnum)))
                    break;
            }
        }
        else {
            while(1) {
                if ((val == 1) &&
                    (*(ushort *)PBDAT&(ushort)~(0x0001<<bitnum)))
                    break;
                else if ((val == 0) &&
                    !(*(ushort *)PBDAT&(ushort)~(0x0001<<bitnum)))
                    break;
            }
        }
        return(0);
    }
    /* If config, then set up direction or control */
    if (config) {
        if (argc != (optind+2))
            return(-1);
        if (portAorB == 'a') {
            switch(config) {
            case PIO_OUT:
                *(ushort *)PADDR |= (ushort)(0x01 << bitnum);
                break;
            case PIO_IN:
                *(ushort *)PADDR &= (ushort)~(0x01 << bitnum);
                break;
            case PIO_GP:
                *(ushort *)PACNT &= (ushort)~(0x01 << bitnum);
                break;
            case PIO_DED:
                *(ushort *)PACNT |= (ushort)(0x01 << bitnum);
                break;
            }
        }
        else {
            switch(config) {
            case PIO_OUT:
                *(ushort *)PBDDR |= (ushort)(0x0001 << bitnum);
                break;
            case PIO_IN:
                *(ushort *)PBDDR &= (ushort)~(0x0001 << bitnum);
                break;
            case PIO_GP:
                *(ushort *)PBCNT &= (ushort)~(0x0001 << bitnum);
                break;
            case PIO_DED:
                *(ushort *)PBCNT |= (ushort)(0x0001 << bitnum);
                break;
            }
        }
        return(0);
    }

    /* If config is not set, then it must be a read or write request... */
    /* If third arg is present, then write; else read. */
    if (argc == optind+3) {
        val = argv[optind+2][0] & 1;
        if (portAorB == 'a') {
            if (val)
                *(ushort *)PADAT |= (ushort)(0x01 << bitnum);
                else
                *(ushort *)PADAT &= (ushort)~(0x01 << bitnum);
        }
        else {
            if (val)
                *(ushort *)PBDAT |= (ushort)(0x0001 << bitnum);
                else
                *(ushort *)PBDAT &= (ushort)~(0x0001 << bitnum);
        }
    }
    else {          /* Read a pio bit */
        if (portAorB == 'a') {
            printf("PA%d = %d\n",bitnum,
                (*(ushort *)PADAT & (ushort)(0x01 << bitnum)) ? 1:0);
        }
        else {
            printf("PB%d = %d\n",bitnum,
                (*(ushort *)PBDAT & (ushort)(0x0001 << bitnum)) ? 1:0);
        }
    }
    return(0);
}

void
pioshow(void)
{
    int i;
    ushort  mask;

    printf("PORTA bits 0-15...\n");
    printf("PACNT: 0x%04x, PADDR: 0x%04x, PADAT: 0x%04x\n",
        *(ushort*)PACNT, *(ushort *)PADDR, *(ushort *)PADAT);
    for (mask=1,i=0;i<16;i++,mask <<= 1) {
        printf("  PA%02d: %s %s %d\n",i,
            (*(ushort *)PACNT & mask) ? "dedicated" : "gpio",
            (*(ushort *)PADDR & mask) ? "output" : "input",
            (*(ushort *)PADAT & mask) ? 1 : 0);
    }
    printf("\nPORTB bits 0-11...\n");
    printf("PBCNT: 0x%04x, PBDDR: 0x%04x, PBDAT: 0x%04x\n",
        *(ushort*)PBCNT, *(ushort *)PBDDR, *(ushort *)PBDAT);
    for (mask=1,i=0;i<12;i++,mask <<= 1) {
        printf("  PB%02d: %s %s %d\n",i,
            (*(ushort *)PBCNT & mask) ? "dedicated" : "gpio",
            (*(ushort *)PBDDR & mask) ? "output" : "input",
            (*(ushort *)PBDAT & mask) ? 1 : 0);
    }
}
#endif

int
pioget(char port,int bitnum)
{
    port = tolower(port);
    if (port == 'a')
        return((*(ushort *)PADAT & (ushort)(0x01 << bitnum)) ? 1:0);
    else if (port == 'b')
        return((*(ushort *)PBDAT & (ushort)(0x0001 << bitnum)) ? 1:0);
    else
        printf("pioget port error\n");
    return(-1);
}

void
pioclr(char port,int bitnum)
{
    port = tolower(port);
    if (port == 'a')
        *(ushort *)PADAT &= (ushort)~(0x01 << bitnum);
    else if (port == 'b')
        *(ushort *)PBDAT &= (ushort)~(0x0001 << bitnum);
    else
        printf("pioclr port error\n");
}

void
pioset(char port,int bitnum)
{
    port = tolower(port);
    if (port == 'a')
        *(ushort *)PADAT |= (ushort)(0x01 << bitnum);
    else if (port == 'b')
        *(ushort *)PBDAT |= (ushort)(0x0001 << bitnum);
    else
        printf("pioset port error\n");
}