suncore.c

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/* suncore.c
 *
 * Common SUN serial routines.  Based entirely
 * upon drivers/sbus/char/sunserial.c which is:
 *
 * Copyright (C) 1997  Eddie C. Dost  ([email protected])
 *
 * Adaptation to new UART layer is:
 *
 * Copyright (C) 2002 David S. Miller ([email protected])
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/console.h>
#include <linux/tty.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/serial_core.h>
#include <linux/sunserialcore.h>
#include <linux/init.h>

#include <asm/prom.h>


static int sunserial_current_minor = 64;

int sunserial_register_minors(struct uart_driver *drv, int count)
{
    int err = 0;

    drv->minor = sunserial_current_minor;
    drv->nr += count;
    /* Register the driver on the first call */
    if (drv->nr == count)
        err = uart_register_driver(drv);
    if (err == 0) {
        sunserial_current_minor += count;
        drv->tty_driver->name_base = drv->minor - 64;
    }
    return err;
}
EXPORT_SYMBOL(sunserial_register_minors);

void sunserial_unregister_minors(struct uart_driver *drv, int count)
{
    drv->nr -= count;
    sunserial_current_minor -= count;

    if (drv->nr == 0)
        uart_unregister_driver(drv);
}
EXPORT_SYMBOL(sunserial_unregister_minors);

int sunserial_console_match(struct console *con, struct device_node *dp,
                struct uart_driver *drv, int line, bool ignore_line)
{
    if (!con)
        return 0;

    drv->cons = con;

    if (of_console_device != dp)
        return 0;

    if (!ignore_line) {
        int off = 0;

        if (of_console_options &&
            *of_console_options == 'b')
            off = 1;

        if ((line & 1) != off)
            return 0;
    }

    if (!console_set_on_cmdline) {
        con->index = line;
        add_preferred_console(con->name, line, NULL);
    }
    return 1;
}
EXPORT_SYMBOL(sunserial_console_match);

void sunserial_console_termios(struct console *con, struct device_node *uart_dp)
{
    const char *mode, *s;
    char mode_prop[] = "ttyX-mode";
    int baud, bits, stop, cflag;
    char parity;

    if (!strcmp(uart_dp->name, "rsc") ||
        !strcmp(uart_dp->name, "rsc-console") ||
        !strcmp(uart_dp->name, "rsc-control")) {
        mode = of_get_property(uart_dp,
                       "ssp-console-modes", NULL);
        if (!mode)
            mode = "115200,8,n,1,-";
    } else if (!strcmp(uart_dp->name, "lom-console")) {
        mode = "9600,8,n,1,-";
    } else {
        struct device_node *dp;
        char c;

        c = 'a';
        if (of_console_options)
            c = *of_console_options;

        mode_prop[3] = c;

        dp = of_find_node_by_path("/options");
        mode = of_get_property(dp, mode_prop, NULL);
        if (!mode)
            mode = "9600,8,n,1,-";
    }

    cflag = CREAD | HUPCL | CLOCAL;

    s = mode;
    baud = simple_strtoul(s, NULL, 0);
    s = strchr(s, ',');
    bits = simple_strtoul(++s, NULL, 0);
    s = strchr(s, ',');
    parity = *(++s);
    s = strchr(s, ',');
    stop = simple_strtoul(++s, NULL, 0);
    s = strchr(s, ',');
    /* XXX handshake is not handled here. */

    switch (baud) {
        case 150: cflag |= B150; break;
        case 300: cflag |= B300; break;
        case 600: cflag |= B600; break;
        case 1200: cflag |= B1200; break;
        case 2400: cflag |= B2400; break;
        case 4800: cflag |= B4800; break;
        case 9600: cflag |= B9600; break;
        case 19200: cflag |= B19200; break;
        case 38400: cflag |= B38400; break;
        case 57600: cflag |= B57600; break;
        case 115200: cflag |= B115200; break;
        case 230400: cflag |= B230400; break;
        case 460800: cflag |= B460800; break;
        default: baud = 9600; cflag |= B9600; break;
    }

    switch (bits) {
        case 5: cflag |= CS5; break;
        case 6: cflag |= CS6; break;
        case 7: cflag |= CS7; break;
        case 8: cflag |= CS8; break;
        default: cflag |= CS8; break;
    }

    switch (parity) {
        case 'o': cflag |= (PARENB | PARODD); break;
        case 'e': cflag |= PARENB; break;
        case 'n': default: break;
    }

    switch (stop) {
        case 2: cflag |= CSTOPB; break;
        case 1: default: break;
    }

    con->cflag = cflag;
}

/* Sun serial MOUSE auto baud rate detection.  */
static struct mouse_baud_cflag {
    int baud;
    unsigned int cflag;
} mouse_baud_table[] = {
    { 1200, B1200 },
    { 2400, B2400 },
    { 4800, B4800 },
    { 9600, B9600 },
    { -1, ~0 },
    { -1, ~0 },
};

unsigned int suncore_mouse_baud_cflag_next(unsigned int cflag, int *new_baud)
{
    int i;

    for (i = 0; mouse_baud_table[i].baud != -1; i++)
        if (mouse_baud_table[i].cflag == (cflag & CBAUD))
            break;

    i += 1;
    if (mouse_baud_table[i].baud == -1)
        i = 0;

    *new_baud = mouse_baud_table[i].baud;
    return mouse_baud_table[i].cflag;
}

EXPORT_SYMBOL(suncore_mouse_baud_cflag_next);

/* Basically, when the baud rate is wrong the mouse spits out
 * breaks to us.
 */
int suncore_mouse_baud_detection(unsigned char ch, int is_break)
{
    static int mouse_got_break = 0;
    static int ctr = 0;

    if (is_break) {
        /* Let a few normal bytes go by before we jump the gun
         * and say we need to try another baud rate.
         */
        if (mouse_got_break && ctr < 8)
            return 1;

        /* Ok, we need to try another baud. */
        ctr = 0;
        mouse_got_break = 1;
        return 2;
    }
    if (mouse_got_break) {
        ctr++;
        if (ch == 0x87) {
            /* Correct baud rate determined. */
            mouse_got_break = 0;
        }
        return 1;
    }
    return 0;
}

EXPORT_SYMBOL(suncore_mouse_baud_detection);

static int __init suncore_init(void)
{
    return 0;
}

static void __exit suncore_exit(void)
{
}

module_init(suncore_init);
module_exit(suncore_exit);

MODULE_AUTHOR("Eddie C. Dost, David S. Miller");
MODULE_DESCRIPTION("Sun serial common layer");
MODULE_LICENSE("GPL");