drivers/vfio/platform/vfio_platform.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2013 - Virtual Open Systems
   4  * Author: Antonios Motakis <a.motakis@virtualopensystems.com>
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/slab.h>
   9 #include <linux/vfio.h>
  10 #include <linux/platform_device.h>
  11
  12 #include "vfio_platform_private.h"
  13
  14 #define DRIVER_VERSION  "0.10"
  15 #define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
  16 #define DRIVER_DESC     "VFIO for platform devices - User Level meta-driver"
  17
  18 static bool reset_required = true;
  19 module_param(reset_required, bool, 0444);
  20 MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)");
  21
  22 /* probing devices from the linux platform bus */
  23
  24 static struct resource *get_platform_resource(struct vfio_platform_device *vdev,
  25                                               int num)
  26 {
  27         struct platform_device *dev = (struct platform_device *) vdev->opaque;
  28         int i;
  29
  30         for (i = 0; i < dev->num_resources; i++) {
  31                 struct resource *r = &dev->resource[i];
  32
  33                 if (resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) {
  34                         if (!num)
  35                                 return r;
  36
  37                         num--;
  38                 }
  39         }
  40         return NULL;
  41 }
  42
  43 static int get_platform_irq(struct vfio_platform_device *vdev, int i)
  44 {
  45         struct platform_device *pdev = (struct platform_device *) vdev->opaque;
  46
  47         return platform_get_irq_optional(pdev, i);
  48 }
  49
  50 static int vfio_platform_probe(struct platform_device *pdev)
  51 {
  52         struct vfio_platform_device *vdev;
  53         int ret;
  54
  55         vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
  56         if (!vdev)
  57                 return -ENOMEM;
  58
  59         vdev->opaque = (void *) pdev;
  60         vdev->name = pdev->name;
  61         vdev->flags = VFIO_DEVICE_FLAGS_PLATFORM;
  62         vdev->get_resource = get_platform_resource;
  63         vdev->get_irq = get_platform_irq;
  64         vdev->parent_module = THIS_MODULE;
  65         vdev->reset_required = reset_required;
  66
  67         ret = vfio_platform_probe_common(vdev, &pdev->dev);
  68         if (ret)
  69                 kfree(vdev);
  70
  71         return ret;
  72 }
  73
  74 static int vfio_platform_remove(struct platform_device *pdev)
  75 {
  76         struct vfio_platform_device *vdev;
  77
  78         vdev = vfio_platform_remove_common(&pdev->dev);
  79         if (vdev) {
  80                 kfree(vdev);
  81                 return 0;
  82         }
  83
  84         return -EINVAL;
  85 }
  86
  87 static struct platform_driver vfio_platform_driver = {
  88         .probe          = vfio_platform_probe,
  89         .remove         = vfio_platform_remove,
  90         .driver = {
  91                 .name   = "vfio-platform",
  92         },
  93 };
  94
  95 module_platform_driver(vfio_platform_driver);
  96
  97 MODULE_VERSION(DRIVER_VERSION);
  98 MODULE_LICENSE("GPL v2");
  99 MODULE_AUTHOR(DRIVER_AUTHOR);
 100 MODULE_DESCRIPTION(DRIVER_DESC);