1// SPDX-License-Identifier: GPL-2.0
2/*
3 * ISA bus.
4 */
5
6#include <linux/device.h>
7#include <linux/kernel.h>
8#include <linux/slab.h>
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/dma-mapping.h>
12#include <linux/isa.h>
13
14static struct device isa_bus = {
15	.init_name	= "isa"
16};
17
18struct isa_dev {
19	struct device dev;
20	struct device *next;
21	unsigned int id;
22};
23
24#define to_isa_dev(x) container_of((x), struct isa_dev, dev)
25
26static int isa_bus_match(struct device *dev, struct device_driver *driver)
27{
28	struct isa_driver *isa_driver = to_isa_driver(driver);
29
30	if (dev->platform_data == isa_driver) {
31		if (!isa_driver->match ||
32			isa_driver->match(dev, to_isa_dev(dev)->id))
33			return 1;
34		dev->platform_data = NULL;
35	}
36	return 0;
37}
38
39static int isa_bus_probe(struct device *dev)
40{
41	struct isa_driver *isa_driver = dev->platform_data;
42
43	if (isa_driver && isa_driver->probe)
44		return isa_driver->probe(dev, to_isa_dev(dev)->id);
45
46	return 0;
47}
48
49static void isa_bus_remove(struct device *dev)
50{
51	struct isa_driver *isa_driver = dev->platform_data;
52
53	if (isa_driver && isa_driver->remove)
54		isa_driver->remove(dev, to_isa_dev(dev)->id);
55}
56
57static void isa_bus_shutdown(struct device *dev)
58{
59	struct isa_driver *isa_driver = dev->platform_data;
60
61	if (isa_driver && isa_driver->shutdown)
62		isa_driver->shutdown(dev, to_isa_dev(dev)->id);
63}
64
65static int isa_bus_suspend(struct device *dev, pm_message_t state)
66{
67	struct isa_driver *isa_driver = dev->platform_data;
68
69	if (isa_driver && isa_driver->suspend)
70		return isa_driver->suspend(dev, to_isa_dev(dev)->id, state);
71
72	return 0;
73}
74
75static int isa_bus_resume(struct device *dev)
76{
77	struct isa_driver *isa_driver = dev->platform_data;
78
79	if (isa_driver && isa_driver->resume)
80		return isa_driver->resume(dev, to_isa_dev(dev)->id);
81
82	return 0;
83}
84
85static const struct bus_type isa_bus_type = {
86	.name		= "isa",
87	.match		= isa_bus_match,
88	.probe		= isa_bus_probe,
89	.remove		= isa_bus_remove,
90	.shutdown	= isa_bus_shutdown,
91	.suspend	= isa_bus_suspend,
92	.resume		= isa_bus_resume
93};
94
95static void isa_dev_release(struct device *dev)
96{
97	kfree(to_isa_dev(dev));
98}
99
100void isa_unregister_driver(struct isa_driver *isa_driver)
101{
102	struct device *dev = isa_driver->devices;
103
104	while (dev) {
105		struct device *tmp = to_isa_dev(dev)->next;
106		device_unregister(dev);
107		dev = tmp;
108	}
109	driver_unregister(&isa_driver->driver);
110}
111EXPORT_SYMBOL_GPL(isa_unregister_driver);
112
113int isa_register_driver(struct isa_driver *isa_driver, unsigned int ndev)
114{
115	int error;
116	unsigned int id;
117
118	isa_driver->driver.bus	= &isa_bus_type;
119	isa_driver->devices	= NULL;
120
121	error = driver_register(&isa_driver->driver);
122	if (error)
123		return error;
124
125	for (id = 0; id < ndev; id++) {
126		struct isa_dev *isa_dev;
127
128		isa_dev = kzalloc(sizeof *isa_dev, GFP_KERNEL);
129		if (!isa_dev) {
130			error = -ENOMEM;
131			break;
132		}
133
134		isa_dev->dev.parent	= &isa_bus;
135		isa_dev->dev.bus	= &isa_bus_type;
136
137		dev_set_name(&isa_dev->dev, "%s.%u",
138			     isa_driver->driver.name, id);
139		isa_dev->dev.platform_data	= isa_driver;
140		isa_dev->dev.release		= isa_dev_release;
141		isa_dev->id			= id;
142
143		isa_dev->dev.coherent_dma_mask = DMA_BIT_MASK(24);
144		isa_dev->dev.dma_mask = &isa_dev->dev.coherent_dma_mask;
145
146		error = device_register(&isa_dev->dev);
147		if (error) {
148			put_device(&isa_dev->dev);
149			break;
150		}
151
152		isa_dev->next = isa_driver->devices;
153		isa_driver->devices = &isa_dev->dev;
154	}
155
156	if (!error && !isa_driver->devices)
157		error = -ENODEV;
158
159	if (error)
160		isa_unregister_driver(isa_driver);
161
162	return error;
163}
164EXPORT_SYMBOL_GPL(isa_register_driver);
165
166static int __init isa_bus_init(void)
167{
168	int error;
169
170	error = bus_register(&isa_bus_type);
171	if (!error) {
172		error = device_register(&isa_bus);
173		if (error)
174			bus_unregister(&isa_bus_type);
175	}
176	return error;
177}
178
179postcore_initcall(isa_bus_init);
180