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