1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Copyright(c) 2021 Intel Corporation. All rights rsvd. */ |
3 | #include <linux/init.h> |
4 | #include <linux/kernel.h> |
5 | #include <linux/module.h> |
6 | #include <linux/device.h> |
7 | #include <linux/device/bus.h> |
8 | #include "idxd.h" |
9 | |
10 | extern int device_driver_attach(struct device_driver *drv, struct device *dev); |
11 | extern void device_driver_detach(struct device *dev); |
12 | |
13 | #define DRIVER_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \ |
14 | struct driver_attribute driver_attr_##_name = \ |
15 | __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) |
16 | |
17 | static ssize_t unbind_store(struct device_driver *drv, const char *buf, size_t count) |
18 | { |
19 | const struct bus_type *bus = drv->bus; |
20 | struct device *dev; |
21 | int rc = -ENODEV; |
22 | |
23 | dev = bus_find_device_by_name(bus, NULL, name: buf); |
24 | if (dev && dev->driver) { |
25 | device_driver_detach(dev); |
26 | rc = count; |
27 | } |
28 | |
29 | return rc; |
30 | } |
31 | static DRIVER_ATTR_IGNORE_LOCKDEP(unbind, 0200, NULL, unbind_store); |
32 | |
33 | static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t count) |
34 | { |
35 | const struct bus_type *bus = drv->bus; |
36 | struct device *dev; |
37 | struct device_driver *alt_drv = NULL; |
38 | int rc = -ENODEV; |
39 | struct idxd_dev *idxd_dev; |
40 | |
41 | dev = bus_find_device_by_name(bus, NULL, name: buf); |
42 | if (!dev || dev->driver || drv != &dsa_drv.drv) |
43 | return -ENODEV; |
44 | |
45 | idxd_dev = confdev_to_idxd_dev(dev); |
46 | if (is_idxd_dev(idxd_dev)) { |
47 | alt_drv = driver_find(name: "idxd" , bus); |
48 | } else if (is_idxd_wq_dev(idxd_dev)) { |
49 | struct idxd_wq *wq = confdev_to_wq(dev); |
50 | |
51 | if (is_idxd_wq_kernel(wq)) |
52 | alt_drv = driver_find(name: "dmaengine" , bus); |
53 | else if (is_idxd_wq_user(wq)) |
54 | alt_drv = driver_find(name: "user" , bus); |
55 | } |
56 | if (!alt_drv) |
57 | return -ENODEV; |
58 | |
59 | rc = device_driver_attach(drv: alt_drv, dev); |
60 | if (rc < 0) |
61 | return rc; |
62 | |
63 | return count; |
64 | } |
65 | static DRIVER_ATTR_IGNORE_LOCKDEP(bind, 0200, NULL, bind_store); |
66 | |
67 | static struct attribute *dsa_drv_compat_attrs[] = { |
68 | &driver_attr_bind.attr, |
69 | &driver_attr_unbind.attr, |
70 | NULL, |
71 | }; |
72 | |
73 | static const struct attribute_group dsa_drv_compat_attr_group = { |
74 | .attrs = dsa_drv_compat_attrs, |
75 | }; |
76 | |
77 | static const struct attribute_group *dsa_drv_compat_groups[] = { |
78 | &dsa_drv_compat_attr_group, |
79 | NULL, |
80 | }; |
81 | |
82 | static int idxd_dsa_drv_probe(struct idxd_dev *idxd_dev) |
83 | { |
84 | return -ENODEV; |
85 | } |
86 | |
87 | static void idxd_dsa_drv_remove(struct idxd_dev *idxd_dev) |
88 | { |
89 | } |
90 | |
91 | static enum idxd_dev_type dev_types[] = { |
92 | IDXD_DEV_NONE, |
93 | }; |
94 | |
95 | struct idxd_device_driver dsa_drv = { |
96 | .name = "dsa" , |
97 | .probe = idxd_dsa_drv_probe, |
98 | .remove = idxd_dsa_drv_remove, |
99 | .type = dev_types, |
100 | .drv = { |
101 | .suppress_bind_attrs = true, |
102 | .groups = dsa_drv_compat_groups, |
103 | }, |
104 | }; |
105 | |
106 | module_idxd_driver(dsa_drv); |
107 | MODULE_IMPORT_NS(IDXD); |
108 | |