xref: /kernel/linux/linux-5.10/drivers/base/isa.c (revision 8c2ecf20)
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 int 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		return isa_driver->remove(dev, to_isa_dev(dev)->id);
55
56	return 0;
57}
58
59static void isa_bus_shutdown(struct device *dev)
60{
61	struct isa_driver *isa_driver = dev->platform_data;
62
63	if (isa_driver && isa_driver->shutdown)
64		isa_driver->shutdown(dev, to_isa_dev(dev)->id);
65}
66
67static int isa_bus_suspend(struct device *dev, pm_message_t state)
68{
69	struct isa_driver *isa_driver = dev->platform_data;
70
71	if (isa_driver && isa_driver->suspend)
72		return isa_driver->suspend(dev, to_isa_dev(dev)->id, state);
73
74	return 0;
75}
76
77static int isa_bus_resume(struct device *dev)
78{
79	struct isa_driver *isa_driver = dev->platform_data;
80
81	if (isa_driver && isa_driver->resume)
82		return isa_driver->resume(dev, to_isa_dev(dev)->id);
83
84	return 0;
85}
86
87static struct bus_type isa_bus_type = {
88	.name		= "isa",
89	.match		= isa_bus_match,
90	.probe		= isa_bus_probe,
91	.remove		= isa_bus_remove,
92	.shutdown	= isa_bus_shutdown,
93	.suspend	= isa_bus_suspend,
94	.resume		= isa_bus_resume
95};
96
97static void isa_dev_release(struct device *dev)
98{
99	kfree(to_isa_dev(dev));
100}
101
102void isa_unregister_driver(struct isa_driver *isa_driver)
103{
104	struct device *dev = isa_driver->devices;
105
106	while (dev) {
107		struct device *tmp = to_isa_dev(dev)->next;
108		device_unregister(dev);
109		dev = tmp;
110	}
111	driver_unregister(&isa_driver->driver);
112}
113EXPORT_SYMBOL_GPL(isa_unregister_driver);
114
115int isa_register_driver(struct isa_driver *isa_driver, unsigned int ndev)
116{
117	int error;
118	unsigned int id;
119
120	isa_driver->driver.bus	= &isa_bus_type;
121	isa_driver->devices	= NULL;
122
123	error = driver_register(&isa_driver->driver);
124	if (error)
125		return error;
126
127	for (id = 0; id < ndev; id++) {
128		struct isa_dev *isa_dev;
129
130		isa_dev = kzalloc(sizeof *isa_dev, GFP_KERNEL);
131		if (!isa_dev) {
132			error = -ENOMEM;
133			break;
134		}
135
136		isa_dev->dev.parent	= &isa_bus;
137		isa_dev->dev.bus	= &isa_bus_type;
138
139		dev_set_name(&isa_dev->dev, "%s.%u",
140			     isa_driver->driver.name, id);
141		isa_dev->dev.platform_data	= isa_driver;
142		isa_dev->dev.release		= isa_dev_release;
143		isa_dev->id			= id;
144
145		isa_dev->dev.coherent_dma_mask = DMA_BIT_MASK(24);
146		isa_dev->dev.dma_mask = &isa_dev->dev.coherent_dma_mask;
147
148		error = device_register(&isa_dev->dev);
149		if (error) {
150			put_device(&isa_dev->dev);
151			break;
152		}
153
154		if (isa_dev->dev.platform_data) {
155			isa_dev->next = isa_driver->devices;
156			isa_driver->devices = &isa_dev->dev;
157		} else
158			device_unregister(&isa_dev->dev);
159	}
160
161	if (!error && !isa_driver->devices)
162		error = -ENODEV;
163
164	if (error)
165		isa_unregister_driver(isa_driver);
166
167	return error;
168}
169EXPORT_SYMBOL_GPL(isa_register_driver);
170
171static int __init isa_bus_init(void)
172{
173	int error;
174
175	error = bus_register(&isa_bus_type);
176	if (!error) {
177		error = device_register(&isa_bus);
178		if (error)
179			bus_unregister(&isa_bus_type);
180	}
181	return error;
182}
183
184postcore_initcall(isa_bus_init);
185