1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * vchiq_device.c - VCHIQ generic device and bus-type
4 *
5 * Copyright (c) 2023 Ideas On Board Oy
6 */
7
8 #include <linux/device/bus.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/of_device.h>
11 #include <linux/slab.h>
12 #include <linux/string.h>
13
14 #include "vchiq_bus.h"
15
vchiq_bus_type_match(struct device * dev,struct device_driver * drv)16 static int vchiq_bus_type_match(struct device *dev, struct device_driver *drv)
17 {
18 if (dev->bus == &vchiq_bus_type &&
19 strcmp(dev_name(dev), drv->name) == 0)
20 return true;
21
22 return false;
23 }
24
vchiq_bus_uevent(const struct device * dev,struct kobj_uevent_env * env)25 static int vchiq_bus_uevent(const struct device *dev, struct kobj_uevent_env *env)
26 {
27 const struct vchiq_device *device = container_of_const(dev, struct vchiq_device, dev);
28
29 return add_uevent_var(env, "MODALIAS=vchiq:%s", dev_name(&device->dev));
30 }
31
vchiq_bus_probe(struct device * dev)32 static int vchiq_bus_probe(struct device *dev)
33 {
34 struct vchiq_device *device = to_vchiq_device(dev);
35 struct vchiq_driver *driver = to_vchiq_driver(dev->driver);
36
37 return driver->probe(device);
38 }
39
40 struct bus_type vchiq_bus_type = {
41 .name = "vchiq-bus",
42 .match = vchiq_bus_type_match,
43 .uevent = vchiq_bus_uevent,
44 .probe = vchiq_bus_probe,
45 };
46
vchiq_device_release(struct device * dev)47 static void vchiq_device_release(struct device *dev)
48 {
49 struct vchiq_device *device = to_vchiq_device(dev);
50
51 kfree(device);
52 }
53
54 struct vchiq_device *
vchiq_device_register(struct device * parent,const char * name)55 vchiq_device_register(struct device *parent, const char *name)
56 {
57 struct vchiq_device *device;
58 int ret;
59
60 device = kzalloc(sizeof(*device), GFP_KERNEL);
61 if (!device)
62 return NULL;
63
64 device->dev.init_name = name;
65 device->dev.parent = parent;
66 device->dev.bus = &vchiq_bus_type;
67 device->dev.dma_mask = &device->dev.coherent_dma_mask;
68 device->dev.release = vchiq_device_release;
69
70 of_dma_configure(&device->dev, parent->of_node, true);
71
72 ret = device_register(&device->dev);
73 if (ret) {
74 dev_err(parent, "Cannot register %s: %d\n", name, ret);
75 put_device(&device->dev);
76 return NULL;
77 }
78
79 return device;
80 }
81
vchiq_device_unregister(struct vchiq_device * vchiq_dev)82 void vchiq_device_unregister(struct vchiq_device *vchiq_dev)
83 {
84 device_unregister(&vchiq_dev->dev);
85 }
86
vchiq_driver_register(struct vchiq_driver * vchiq_drv)87 int vchiq_driver_register(struct vchiq_driver *vchiq_drv)
88 {
89 vchiq_drv->driver.bus = &vchiq_bus_type;
90
91 return driver_register(&vchiq_drv->driver);
92 }
93 EXPORT_SYMBOL_GPL(vchiq_driver_register);
94
vchiq_driver_unregister(struct vchiq_driver * vchiq_drv)95 void vchiq_driver_unregister(struct vchiq_driver *vchiq_drv)
96 {
97 driver_unregister(&vchiq_drv->driver);
98 }
99 EXPORT_SYMBOL_GPL(vchiq_driver_unregister);
100