drivers/vfio/mdev/mdev_driver.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * MDEV driver
   4  *
   5  * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
   6  *     Author: Neo Jia <cjia@nvidia.com>
   7  *             Kirti Wankhede <kwankhede@nvidia.com>
   8  */
   9
  10 #include <linux/device.h>
  11 #include <linux/iommu.h>
  12 #include <linux/mdev.h>
  13
  14 #include "mdev_private.h"
  15
  16 static int mdev_probe(struct device *dev)
  17 {
  18         struct mdev_driver *drv =
  19                 container_of(dev->driver, struct mdev_driver, driver);
  20
  21         if (!drv->probe)
  22                 return 0;
  23         return drv->probe(to_mdev_device(dev));
  24 }
  25
  26 static void mdev_remove(struct device *dev)
  27 {
  28         struct mdev_driver *drv =
  29                 container_of(dev->driver, struct mdev_driver, driver);
  30
  31         if (drv->remove)
  32                 drv->remove(to_mdev_device(dev));
  33 }
  34
  35 static int mdev_match(struct device *dev, struct device_driver *drv)
  36 {
  37         /*
  38          * No drivers automatically match. Drivers are only bound by explicit
  39          * device_driver_attach()
  40          */
  41         return 0;
  42 }
  43
  44 struct bus_type mdev_bus_type = {
  45         .name           = "mdev",
  46         .probe          = mdev_probe,
  47         .remove         = mdev_remove,
  48         .match          = mdev_match,
  49 };
  50 EXPORT_SYMBOL_GPL(mdev_bus_type);
  51
  52 /**
  53  * mdev_register_driver - register a new MDEV driver
  54  * @drv: the driver to register
  55  *
  56  * Returns a negative value on error, otherwise 0.
  57  **/
  58 int mdev_register_driver(struct mdev_driver *drv)
  59 {
  60         /* initialize common driver fields */
  61         drv->driver.bus = &mdev_bus_type;
  62
  63         /* register with core */
  64         return driver_register(&drv->driver);
  65 }
  66 EXPORT_SYMBOL(mdev_register_driver);
  67
  68 /*
  69  * mdev_unregister_driver - unregister MDEV driver
  70  * @drv: the driver to unregister
  71  */
  72 void mdev_unregister_driver(struct mdev_driver *drv)
  73 {
  74         driver_unregister(&drv->driver);
  75 }
  76 EXPORT_SYMBOL(mdev_unregister_driver);