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 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
isa_bus_shutdown(struct device * dev)57 static 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
isa_bus_suspend(struct device * dev,pm_message_t state)65 static 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
isa_bus_resume(struct device * dev)75 static 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
85 static 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
isa_dev_release(struct device * dev)95 static void isa_dev_release(struct device *dev)
96 {
97 kfree(to_isa_dev(dev));
98 }
99
isa_unregister_driver(struct isa_driver * isa_driver)100 void 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 }
111 EXPORT_SYMBOL_GPL(isa_unregister_driver);
112
isa_register_driver(struct isa_driver * isa_driver,unsigned int ndev)113 int 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 }
164 EXPORT_SYMBOL_GPL(isa_register_driver);
165
isa_bus_init(void)166 static 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
179 postcore_initcall(isa_bus_init);
180