1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * MDEV driver
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
6*4882a593Smuzhiyun * Author: Neo Jia <cjia@nvidia.com>
7*4882a593Smuzhiyun * Kirti Wankhede <kwankhede@nvidia.com>
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/device.h>
11*4882a593Smuzhiyun #include <linux/iommu.h>
12*4882a593Smuzhiyun #include <linux/mdev.h>
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun #include "mdev_private.h"
15*4882a593Smuzhiyun
mdev_attach_iommu(struct mdev_device * mdev)16*4882a593Smuzhiyun static int mdev_attach_iommu(struct mdev_device *mdev)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun int ret;
19*4882a593Smuzhiyun struct iommu_group *group;
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun group = iommu_group_alloc();
22*4882a593Smuzhiyun if (IS_ERR(group))
23*4882a593Smuzhiyun return PTR_ERR(group);
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun ret = iommu_group_add_device(group, &mdev->dev);
26*4882a593Smuzhiyun if (!ret)
27*4882a593Smuzhiyun dev_info(&mdev->dev, "MDEV: group_id = %d\n",
28*4882a593Smuzhiyun iommu_group_id(group));
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun iommu_group_put(group);
31*4882a593Smuzhiyun return ret;
32*4882a593Smuzhiyun }
33*4882a593Smuzhiyun
mdev_detach_iommu(struct mdev_device * mdev)34*4882a593Smuzhiyun static void mdev_detach_iommu(struct mdev_device *mdev)
35*4882a593Smuzhiyun {
36*4882a593Smuzhiyun iommu_group_remove_device(&mdev->dev);
37*4882a593Smuzhiyun dev_info(&mdev->dev, "MDEV: detaching iommu\n");
38*4882a593Smuzhiyun }
39*4882a593Smuzhiyun
mdev_probe(struct device * dev)40*4882a593Smuzhiyun static int mdev_probe(struct device *dev)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun struct mdev_driver *drv = to_mdev_driver(dev->driver);
43*4882a593Smuzhiyun struct mdev_device *mdev = to_mdev_device(dev);
44*4882a593Smuzhiyun int ret;
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun ret = mdev_attach_iommu(mdev);
47*4882a593Smuzhiyun if (ret)
48*4882a593Smuzhiyun return ret;
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun if (drv && drv->probe) {
51*4882a593Smuzhiyun ret = drv->probe(dev);
52*4882a593Smuzhiyun if (ret)
53*4882a593Smuzhiyun mdev_detach_iommu(mdev);
54*4882a593Smuzhiyun }
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun return ret;
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
mdev_remove(struct device * dev)59*4882a593Smuzhiyun static int mdev_remove(struct device *dev)
60*4882a593Smuzhiyun {
61*4882a593Smuzhiyun struct mdev_driver *drv = to_mdev_driver(dev->driver);
62*4882a593Smuzhiyun struct mdev_device *mdev = to_mdev_device(dev);
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun if (drv && drv->remove)
65*4882a593Smuzhiyun drv->remove(dev);
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun mdev_detach_iommu(mdev);
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun return 0;
70*4882a593Smuzhiyun }
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun struct bus_type mdev_bus_type = {
73*4882a593Smuzhiyun .name = "mdev",
74*4882a593Smuzhiyun .probe = mdev_probe,
75*4882a593Smuzhiyun .remove = mdev_remove,
76*4882a593Smuzhiyun };
77*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(mdev_bus_type);
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun /**
80*4882a593Smuzhiyun * mdev_register_driver - register a new MDEV driver
81*4882a593Smuzhiyun * @drv: the driver to register
82*4882a593Smuzhiyun * @owner: module owner of driver to be registered
83*4882a593Smuzhiyun *
84*4882a593Smuzhiyun * Returns a negative value on error, otherwise 0.
85*4882a593Smuzhiyun **/
mdev_register_driver(struct mdev_driver * drv,struct module * owner)86*4882a593Smuzhiyun int mdev_register_driver(struct mdev_driver *drv, struct module *owner)
87*4882a593Smuzhiyun {
88*4882a593Smuzhiyun /* initialize common driver fields */
89*4882a593Smuzhiyun drv->driver.name = drv->name;
90*4882a593Smuzhiyun drv->driver.bus = &mdev_bus_type;
91*4882a593Smuzhiyun drv->driver.owner = owner;
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun /* register with core */
94*4882a593Smuzhiyun return driver_register(&drv->driver);
95*4882a593Smuzhiyun }
96*4882a593Smuzhiyun EXPORT_SYMBOL(mdev_register_driver);
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun /*
99*4882a593Smuzhiyun * mdev_unregister_driver - unregister MDEV driver
100*4882a593Smuzhiyun * @drv: the driver to unregister
101*4882a593Smuzhiyun */
mdev_unregister_driver(struct mdev_driver * drv)102*4882a593Smuzhiyun void mdev_unregister_driver(struct mdev_driver *drv)
103*4882a593Smuzhiyun {
104*4882a593Smuzhiyun driver_unregister(&drv->driver);
105*4882a593Smuzhiyun }
106*4882a593Smuzhiyun EXPORT_SYMBOL(mdev_unregister_driver);
107*4882a593Smuzhiyun
mdev_bus_register(void)108*4882a593Smuzhiyun int mdev_bus_register(void)
109*4882a593Smuzhiyun {
110*4882a593Smuzhiyun return bus_register(&mdev_bus_type);
111*4882a593Smuzhiyun }
112*4882a593Smuzhiyun
mdev_bus_unregister(void)113*4882a593Smuzhiyun void mdev_bus_unregister(void)
114*4882a593Smuzhiyun {
115*4882a593Smuzhiyun bus_unregister(&mdev_bus_type);
116*4882a593Smuzhiyun }
117