// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2013 - Virtual Open Systems
 * Author: Antonios Motakis <a.motakis@virtualopensystems.com>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/vfio.h>
#include <linux/pm_runtime.h>
#include <linux/platform_device.h>

#include "vfio_platform_private.h"

#define DRIVER_VERSION  "0.10"
#define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
#define DRIVER_DESC     "VFIO for platform devices - User Level meta-driver"

static bool reset_required = true;
module_param(reset_required, bool, 0444);
MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)");

/* probing devices from the linux platform bus */

static struct resource *get_platform_resource(struct vfio_platform_device *vdev,
                                              int num)
{
        struct platform_device *dev = (struct platform_device *) vdev->opaque;

        return platform_get_mem_or_io(dev, num);
}

static int get_platform_irq(struct vfio_platform_device *vdev, int i)
{
        struct platform_device *pdev = (struct platform_device *) vdev->opaque;

        return platform_get_irq_optional(pdev, i);
}

static int vfio_platform_init_dev(struct vfio_device *core_vdev)
{
        struct vfio_platform_device *vdev =
                container_of(core_vdev, struct vfio_platform_device, vdev);
        struct platform_device *pdev = to_platform_device(core_vdev->dev);

        vdev->opaque = (void *) pdev;
        vdev->name = pdev->name;
        vdev->flags = VFIO_DEVICE_FLAGS_PLATFORM;
        vdev->get_resource = get_platform_resource;
        vdev->get_irq = get_platform_irq;
        vdev->reset_required = reset_required;

        return vfio_platform_init_common(vdev);
}

static const struct vfio_device_ops vfio_platform_ops;
static int vfio_platform_probe(struct platform_device *pdev)
{
        struct vfio_platform_device *vdev;
        int ret;

        vdev = vfio_alloc_device(vfio_platform_device, vdev, &pdev->dev,
                                 &vfio_platform_ops);
        if (IS_ERR(vdev))
                return PTR_ERR(vdev);

        ret = vfio_register_group_dev(&vdev->vdev);
        if (ret)
                goto out_put_vdev;

        pm_runtime_enable(&pdev->dev);
        dev_set_drvdata(&pdev->dev, vdev);
        return 0;

out_put_vdev:
        vfio_put_device(&vdev->vdev);
        return ret;
}

static void vfio_platform_release_dev(struct vfio_device *core_vdev)
{
        struct vfio_platform_device *vdev =
                container_of(core_vdev, struct vfio_platform_device, vdev);

        vfio_platform_release_common(vdev);
}

static void vfio_platform_remove(struct platform_device *pdev)
{
        struct vfio_platform_device *vdev = dev_get_drvdata(&pdev->dev);

        vfio_unregister_group_dev(&vdev->vdev);
        pm_runtime_disable(vdev->device);
        vfio_put_device(&vdev->vdev);
}

static const struct vfio_device_ops vfio_platform_ops = {
        .name           = "vfio-platform",
        .init           = vfio_platform_init_dev,
        .release        = vfio_platform_release_dev,
        .open_device    = vfio_platform_open_device,
        .close_device   = vfio_platform_close_device,
        .ioctl          = vfio_platform_ioctl,
        .get_region_info_caps = vfio_platform_ioctl_get_region_info,
        .read           = vfio_platform_read,
        .write          = vfio_platform_write,
        .mmap           = vfio_platform_mmap,
        .bind_iommufd   = vfio_iommufd_physical_bind,
        .unbind_iommufd = vfio_iommufd_physical_unbind,
        .attach_ioas    = vfio_iommufd_physical_attach_ioas,
        .detach_ioas    = vfio_iommufd_physical_detach_ioas,
};

static struct platform_driver vfio_platform_driver = {
        .probe          = vfio_platform_probe,
        .remove         = vfio_platform_remove,
        .driver = {
                .name   = "vfio-platform",
        },
        .driver_managed_dma = true,
};

module_platform_driver(vfio_platform_driver);

MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);