source: mainline/kernel/genarch/src/kbd/ns16550.c@ a710680

/*
 * Copyright (C) 2001-2004 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.
 */

/** @addtogroup genarch 
 * @{
 */
/**
 * @file
 * @brief       NS 16550 serial port / keyboard driver.
 */

#include <genarch/kbd/ns16550.h>
#include <genarch/kbd/key.h>
#include <genarch/kbd/scanc.h>
#include <genarch/kbd/scanc_sun.h>
#include <arch/drivers/ns16550.h>
#include <arch/interrupt.h>
#include <cpu.h>
#include <arch/asm.h>
#include <arch.h>
#include <typedefs.h>
#include <console/chardev.h>
#include <console/console.h>
#include <interrupt.h>

#define LSR_DATA_READY  0x01

/*
 * These codes read from ns16550 data register are silently ignored.
 */
#define IGNORE_CODE     0x7f            /* all keys up */

static void ns16550_suspend(chardev_t *);
static void ns16550_resume(chardev_t *);

chardev_t kbrd;
static chardev_operations_t ops = {
        .suspend = ns16550_suspend,
        .resume = ns16550_resume,
        .read = key_read
};

void ns16550_interrupt(int n, istate_t *istate);
void ns16550_wait(void);

/** Initialize keyboard and service interrupts using kernel routine */
void ns16550_grab(void)
{
        /* TODO */
}

/** Resume the former interrupt vector */
void ns16550_release(void)
{
        /* TODO */
}

/** Initialize ns16550. */
void ns16550_init(void)
{
        ns16550_grab();
        chardev_initialize("ns16550_kbd", &kbrd, &ops);
        stdin = &kbrd;
}

/** Process ns16550 interrupt.
 *
 * @param n Interrupt vector.
 * @param istate Interrupted state.
 */
void ns16550_interrupt(int n, istate_t *istate)
{
        /* TODO */
}

/** Wait until the controller reads its data. */
void ns16550_wait(void) {
}

/* Called from getc(). */
void ns16550_resume(chardev_t *d)
{
}

/* Called from getc(). */
void ns16550_suspend(chardev_t *d)
{
}

char key_read(chardev_t *d)
{
        char ch;        

        while(!(ch = active_read_buff_read())) {
                uint8_t x;
                while (!(ns16550_lsr_read() & LSR_DATA_READY))
                        ;
                x = ns16550_rbr_read();
                if (x != IGNORE_CODE) {
                        if (x & KEY_RELEASE)
                                key_released(x ^ KEY_RELEASE);
                        else
                                active_read_key_pressed(x);
                }
        }
        return ch;
}

/** Poll for key press and release events.
 *
 * This function can be used to implement keyboard polling.
 */
void ns16550_poll(void)
{
        uint8_t x;

        while (((x = ns16550_lsr_read() & LSR_DATA_READY))) {
                x = ns16550_rbr_read();
                if (x != IGNORE_CODE) {
                        if (x & KEY_RELEASE)
                                key_released(x ^ KEY_RELEASE);
                        else
                                key_pressed(x);
                }
        }
}

/** @}
 */