i8042.c

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/*
 * Copyright (c) 2001-2004 Jakub Jermar
 * Copyright (c) 2006 Josef Cejka
 * Copyright (c) 2009 Jiri Svoboda
 * 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.
 */

#include <ddi.h>
#include <libarch/ddi.h>
#include <devmap.h>
#include <async.h>
#include <unistd.h>
#include <sysinfo.h>
#include <stdio.h>
#include <errno.h>
#include <inttypes.h>

#include "i8042.h"

#define NAME "i8042"
#define NAMESPACE "char"

/* Interesting bits for status register */
#define i8042_OUTPUT_FULL       0x01
#define i8042_INPUT_FULL        0x02
#define i8042_AUX_DATA          0x20

/* Command constants */
#define i8042_CMD_WRITE_CMDB    0x60    
#define i8042_CMD_WRITE_AUX     0xd4    
/* Command byte fields */
#define i8042_KBD_IE            0x01
#define i8042_AUX_IE            0x02
#define i8042_KBD_DISABLE       0x10
#define i8042_AUX_DISABLE       0x20
#define i8042_KBD_TRANSLATE     0x40


enum {
        DEVID_PRI = 0, 
        DEVID_AUX = 1, 
        MAX_DEVS  = 2
};

static irq_cmd_t i8042_cmds[] = {
        {
                .cmd = CMD_PIO_READ_8,
                .addr = NULL,   /* will be patched in run-time */
                .dstarg = 1
        },
        {
                .cmd = CMD_BTEST,
                .value = i8042_OUTPUT_FULL,
                .srcarg = 1,
                .dstarg = 3
        },
        {
                .cmd = CMD_PREDICATE,
                .value = 2,
                .srcarg = 3
        },
        {
                .cmd = CMD_PIO_READ_8,
                .addr = NULL,   /* will be patched in run-time */
                .dstarg = 2
        },
        {
                .cmd = CMD_ACCEPT
        }
};

static irq_code_t i8042_kbd = {
        sizeof(i8042_cmds) / sizeof(irq_cmd_t),
        i8042_cmds
};

static uintptr_t i8042_physical;
static uintptr_t i8042_kernel;
static i8042_t * i8042;

static i8042_port_t i8042_port[MAX_DEVS];

static void wait_ready(void)
{
        while (pio_read_8(&i8042->status) & i8042_INPUT_FULL);
}

static void i8042_irq_handler(ipc_callid_t iid, ipc_call_t *call);
static void i8042_connection(ipc_callid_t iid, ipc_call_t *icall);
static int i8042_init(void);
static void i8042_port_write(int devid, uint8_t data);


int main(int argc, char *argv[])
{
        char name[16];
        int i, rc;
        char dchar[MAX_DEVS] = { 'a', 'b' };

        printf(NAME ": i8042 PS/2 port driver\n");

        rc = devmap_driver_register(NAME, i8042_connection);
        if (rc < 0) {
                printf(NAME ": Unable to register driver.\n");
                return rc;
        }

        if (i8042_init() != EOK)
                return -1;

        for (i = 0; i < MAX_DEVS; i++) {
                i8042_port[i].client_phone = -1;

                snprintf(name, 16, "%s/ps2%c", NAMESPACE, dchar[i]);
                rc = devmap_device_register(name, &i8042_port[i].devmap_handle);
                if (rc != EOK) {
                        printf(NAME ": Unable to register device %s.\n", name);
                        return rc;
                }
                printf(NAME ": Registered device %s\n", name);
        }

        printf(NAME ": Accepting connections\n");
        task_retval(0);
        async_manager();

        /* Not reached */
        return 0;
}

static int i8042_init(void)
{
        if (sysinfo_get_value("i8042.address.physical", &i8042_physical) != EOK)
                return -1;
        
        if (sysinfo_get_value("i8042.address.kernel", &i8042_kernel) != EOK)
                return -1;
        
        void *vaddr;
        if (pio_enable((void *) i8042_physical, sizeof(i8042_t), &vaddr) != 0)
                return -1;
        
        i8042 = vaddr;
        
        sysarg_t inr_a;
        sysarg_t inr_b;
        
        if (sysinfo_get_value("i8042.inr_a", &inr_a) != EOK)
                return -1;
        
        if (sysinfo_get_value("i8042.inr_b", &inr_b) != EOK)
                return -1;
        
        async_set_interrupt_received(i8042_irq_handler);
        
        /* Disable kbd and aux */
        wait_ready();
        pio_write_8(&i8042->status, i8042_CMD_WRITE_CMDB);
        wait_ready();
        pio_write_8(&i8042->data, i8042_KBD_DISABLE | i8042_AUX_DISABLE);

        /* Flush all current IO */
        while (pio_read_8(&i8042->status) & i8042_OUTPUT_FULL)
                (void) pio_read_8(&i8042->data);

        i8042_kbd.cmds[0].addr = (void *) &((i8042_t *) i8042_kernel)->status;
        i8042_kbd.cmds[3].addr = (void *) &((i8042_t *) i8042_kernel)->data;
        register_irq(inr_a, device_assign_devno(), 0, &i8042_kbd);
        register_irq(inr_b, device_assign_devno(), 0, &i8042_kbd);
        printf("%s: registered for interrupts %" PRIun " and %" PRIun "\n",
            NAME, inr_a, inr_b);

        wait_ready();
        pio_write_8(&i8042->status, i8042_CMD_WRITE_CMDB);
        wait_ready();
        pio_write_8(&i8042->data, i8042_KBD_IE | i8042_KBD_TRANSLATE |
            i8042_AUX_IE);

        return 0;
}

static void i8042_connection(ipc_callid_t iid, ipc_call_t *icall)
{
        ipc_callid_t callid;
        ipc_call_t call;
        sysarg_t method;
        devmap_handle_t dh;
        int retval;
        int dev_id, i;

        printf(NAME ": connection handler\n");

        /* Get the device handle. */
        dh = IPC_GET_ARG1(*icall);

        /* Determine which disk device is the client connecting to. */
        dev_id = -1;
        for (i = 0; i < MAX_DEVS; i++) {
                if (i8042_port[i].devmap_handle == dh)
                        dev_id = i;
        }

        if (dev_id < 0) {
                async_answer_0(iid, EINVAL);
                return;
        }

        /* Answer the IPC_M_CONNECT_ME_TO call. */
        async_answer_0(iid, EOK);

        printf(NAME ": accepted connection\n");

        while (1) {
                callid = async_get_call(&call);
                method = IPC_GET_IMETHOD(call);
                switch (method) {
                case IPC_M_PHONE_HUNGUP:
                        /* The other side has hung up. */
                        async_answer_0(callid, EOK);
                        return;
                case IPC_M_CONNECT_TO_ME:
                        printf(NAME ": creating callback connection\n");
                        if (i8042_port[dev_id].client_phone != -1) {
                                retval = ELIMIT;
                                break;
                        }
                        i8042_port[dev_id].client_phone = IPC_GET_ARG5(call);
                        retval = 0;
                        break;
                case IPC_FIRST_USER_METHOD:
                        printf(NAME ": write %" PRIun " to devid %d\n",
                            IPC_GET_ARG1(call), dev_id);
                        i8042_port_write(dev_id, IPC_GET_ARG1(call));
                        retval = 0;
                        break;
                default:
                        retval = EINVAL;
                        break;
                }
                async_answer_0(callid, retval);
        }
}

void i8042_port_write(int devid, uint8_t data)
{
        if (devid == DEVID_AUX) {
                wait_ready();
                pio_write_8(&i8042->status, i8042_CMD_WRITE_AUX);
        }
        wait_ready();
        pio_write_8(&i8042->data, data);
}

static void i8042_irq_handler(ipc_callid_t iid, ipc_call_t *call)
{
        int status, data;
        int devid;

        status = IPC_GET_ARG1(*call);
        data = IPC_GET_ARG2(*call);

        if ((status & i8042_AUX_DATA)) {
                devid = DEVID_AUX;
        } else {
                devid = DEVID_PRI;
        }

        if (i8042_port[devid].client_phone != -1) {
                async_msg_1(i8042_port[devid].client_phone,
                    IPC_FIRST_USER_METHOD, data);
        }
}

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