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
14 static struct device isa_bus = {
15 .init_name = "isa"
16 };
17
18 struct 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
isa_bus_match(struct device * dev,struct device_driver * driver)26 static 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
isa_bus_probe(struct device * dev)39 static 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
isa_bus_remove(struct device * dev)49 static 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
isa_bus_shutdown(struct device * dev)59 static 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
isa_bus_suspend(struct device * dev,pm_message_t state)67 static 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
isa_bus_resume(struct device * dev)77 static 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
87 static 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
isa_dev_release(struct device * dev)97 static void isa_dev_release(struct device *dev)
98 {
99 kfree(to_isa_dev(dev));
100 }
101
isa_unregister_driver(struct isa_driver * isa_driver)102 void 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 }
113 EXPORT_SYMBOL_GPL(isa_unregister_driver);
114
isa_register_driver(struct isa_driver * isa_driver,unsigned int ndev)115 int 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 }
169 EXPORT_SYMBOL_GPL(isa_register_driver);
170
isa_bus_init(void)171 static 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
184 postcore_initcall(isa_bus_init);
185
