// SPDX-License-Identifier: GPL-2.0
/*
 * Provide diagnose information via misc device /dev/diag.
 *
 * Copyright IBM Corp. 2024
 */

#include <linux/fs.h>
#include <linux/init.h>
#include <linux/ioctl.h>
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/types.h>

#include <uapi/asm/diag.h>
#include "diag_ioctl.h"

static long diag_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
        long rc;

        switch (cmd) {
        case DIAG324_GET_PIBLEN:
                rc = diag324_piblen(arg);
                break;
        case DIAG324_GET_PIBBUF:
                rc = diag324_pibbuf(arg);
                break;
        case DIAG310_GET_STRIDE:
                rc = diag310_memtop_stride(arg);
                break;
        case DIAG310_GET_MEMTOPLEN:
                rc = diag310_memtop_len(arg);
                break;
        case DIAG310_GET_MEMTOPBUF:
                rc = diag310_memtop_buf(arg);
                break;
        default:
                rc = -ENOIOCTLCMD;
                break;
        }
        return rc;
}

static const struct file_operations fops = {
        .owner          = THIS_MODULE,
        .open           = nonseekable_open,
        .unlocked_ioctl = diag_ioctl,
};

static struct miscdevice diagdev = {
        .name   = "diag",
        .minor  = MISC_DYNAMIC_MINOR,
        .fops   = &fops,
        .mode   = 0444,
};

static int diag_init(void)
{
        return misc_register(&diagdev);
}

device_initcall(diag_init);