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
 16static int mdev_attach_iommu(struct mdev_device *mdev)
 17{
 18	int ret;
 19	struct iommu_group *group;
 20
 21	group = iommu_group_alloc();
 22	if (IS_ERR(group))
 23		return PTR_ERR(group);
 24
 25	ret = iommu_group_add_device(group, &mdev->dev);
 26	if (!ret)
 27		dev_info(&mdev->dev, "MDEV: group_id = %d\n",
 28			 iommu_group_id(group));
 29
 30	iommu_group_put(group);
 31	return ret;
 
 32}
 33
 34static void mdev_detach_iommu(struct mdev_device *mdev)
 35{
 36	iommu_group_remove_device(&mdev->dev);
 37	dev_info(&mdev->dev, "MDEV: detaching iommu\n");
 38}
 39
 40static int mdev_probe(struct device *dev)
 41{
 42	struct mdev_driver *drv = to_mdev_driver(dev->driver);
 43	struct mdev_device *mdev = to_mdev_device(dev);
 44	int ret;
 45
 46	ret = mdev_attach_iommu(mdev);
 47	if (ret)
 48		return ret;
 49
 50	if (drv && drv->probe) {
 51		ret = drv->probe(dev);
 52		if (ret)
 53			mdev_detach_iommu(mdev);
 54	}
 55
 56	return ret;
 57}
 58
 59static int mdev_remove(struct device *dev)
 60{
 61	struct mdev_driver *drv = to_mdev_driver(dev->driver);
 62	struct mdev_device *mdev = to_mdev_device(dev);
 63
 64	if (drv && drv->remove)
 65		drv->remove(dev);
 66
 67	mdev_detach_iommu(mdev);
 68
 69	return 0;
 70}
 71
 72struct bus_type mdev_bus_type = {
 73	.name		= "mdev",
 74	.probe		= mdev_probe,
 75	.remove		= mdev_remove,
 
 76};
 77EXPORT_SYMBOL_GPL(mdev_bus_type);
 78
 79/**
 80 * mdev_register_driver - register a new MDEV driver
 81 * @drv: the driver to register
 82 * @owner: module owner of driver to be registered
 83 *
 84 * Returns a negative value on error, otherwise 0.
 85 **/
 86int mdev_register_driver(struct mdev_driver *drv, struct module *owner)
 87{
 
 
 
 88	/* initialize common driver fields */
 89	drv->driver.name = drv->name;
 90	drv->driver.bus = &mdev_bus_type;
 91	drv->driver.owner = owner;
 92
 93	/* register with core */
 94	return driver_register(&drv->driver);
 95}
 96EXPORT_SYMBOL(mdev_register_driver);
 97
 98/*
 99 * mdev_unregister_driver - unregister MDEV driver
100 * @drv: the driver to unregister
101 */
102void mdev_unregister_driver(struct mdev_driver *drv)
103{
104	driver_unregister(&drv->driver);
105}
106EXPORT_SYMBOL(mdev_unregister_driver);
107
108int mdev_bus_register(void)
109{
110	return bus_register(&mdev_bus_type);
111}
112
113void mdev_bus_unregister(void)
114{
115	bus_unregister(&mdev_bus_type);
116}

 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/iommu.h>
11#include <linux/mdev.h>
12
13#include "mdev_private.h"
14
15static int mdev_probe(struct device *dev)
16{
17	struct mdev_driver *drv =
18		container_of(dev->driver, struct mdev_driver, driver);
 
 
 
 
 
 
 
 
 
19
20	if (!drv->probe)
21		return 0;
22	return drv->probe(to_mdev_device(dev));
23}
24
25static void mdev_remove(struct device *dev)
26{
27	struct mdev_driver *drv =
28		container_of(dev->driver, struct mdev_driver, driver);
 
29
30	if (drv->remove)
31		drv->remove(to_mdev_device(dev));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
32}
33
34static int mdev_match(struct device *dev, struct device_driver *drv)
35{
36	/*
37	 * No drivers automatically match. Drivers are only bound by explicit
38	 * device_driver_attach()
39	 */
 
 
 
 
40	return 0;
41}
42
43struct bus_type mdev_bus_type = {
44	.name		= "mdev",
45	.probe		= mdev_probe,
46	.remove		= mdev_remove,
47	.match		= mdev_match,
48};
 
49
50/**
51 * mdev_register_driver - register a new MDEV driver
52 * @drv: the driver to register
 
53 *
54 * Returns a negative value on error, otherwise 0.
55 **/
56int mdev_register_driver(struct mdev_driver *drv)
57{
58	if (!drv->device_api)
59		return -EINVAL;
60
61	/* initialize common driver fields */
 
62	drv->driver.bus = &mdev_bus_type;
 
 
 
63	return driver_register(&drv->driver);
64}
65EXPORT_SYMBOL(mdev_register_driver);
66
67/*
68 * mdev_unregister_driver - unregister MDEV driver
69 * @drv: the driver to unregister
70 */
71void mdev_unregister_driver(struct mdev_driver *drv)
72{
73	driver_unregister(&drv->driver);
74}
75EXPORT_SYMBOL(mdev_unregister_driver);