xref: /linux/drivers/base/isa.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 /*
2  * ISA bus.
3  */
4 
5 #include <linux/device.h>
6 #include <linux/kernel.h>
7 #include <linux/slab.h>
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/isa.h>
12 
13 static struct device isa_bus = {
14 	.init_name	= "isa"
15 };
16 
17 struct isa_dev {
18 	struct device dev;
19 	struct device *next;
20 	unsigned int id;
21 };
22 
23 #define to_isa_dev(x) container_of((x), struct isa_dev, dev)
24 
25 static int isa_bus_match(struct device *dev, struct device_driver *driver)
26 {
27 	struct isa_driver *isa_driver = to_isa_driver(driver);
28 
29 	if (dev->platform_data == isa_driver) {
30 		if (!isa_driver->match ||
31 			isa_driver->match(dev, to_isa_dev(dev)->id))
32 			return 1;
33 		dev->platform_data = NULL;
34 	}
35 	return 0;
36 }
37 
38 static int isa_bus_probe(struct device *dev)
39 {
40 	struct isa_driver *isa_driver = dev->platform_data;
41 
42 	if (isa_driver->probe)
43 		return isa_driver->probe(dev, to_isa_dev(dev)->id);
44 
45 	return 0;
46 }
47 
48 static int isa_bus_remove(struct device *dev)
49 {
50 	struct isa_driver *isa_driver = dev->platform_data;
51 
52 	if (isa_driver->remove)
53 		return isa_driver->remove(dev, to_isa_dev(dev)->id);
54 
55 	return 0;
56 }
57 
58 static void isa_bus_shutdown(struct device *dev)
59 {
60 	struct isa_driver *isa_driver = dev->platform_data;
61 
62 	if (isa_driver->shutdown)
63 		isa_driver->shutdown(dev, to_isa_dev(dev)->id);
64 }
65 
66 static int isa_bus_suspend(struct device *dev, pm_message_t state)
67 {
68 	struct isa_driver *isa_driver = dev->platform_data;
69 
70 	if (isa_driver->suspend)
71 		return isa_driver->suspend(dev, to_isa_dev(dev)->id, state);
72 
73 	return 0;
74 }
75 
76 static int isa_bus_resume(struct device *dev)
77 {
78 	struct isa_driver *isa_driver = dev->platform_data;
79 
80 	if (isa_driver->resume)
81 		return isa_driver->resume(dev, to_isa_dev(dev)->id);
82 
83 	return 0;
84 }
85 
86 static struct bus_type isa_bus_type = {
87 	.name		= "isa",
88 	.match		= isa_bus_match,
89 	.probe		= isa_bus_probe,
90 	.remove		= isa_bus_remove,
91 	.shutdown	= isa_bus_shutdown,
92 	.suspend	= isa_bus_suspend,
93 	.resume		= isa_bus_resume
94 };
95 
96 static void isa_dev_release(struct device *dev)
97 {
98 	kfree(to_isa_dev(dev));
99 }
100 
101 void isa_unregister_driver(struct isa_driver *isa_driver)
102 {
103 	struct device *dev = isa_driver->devices;
104 
105 	while (dev) {
106 		struct device *tmp = to_isa_dev(dev)->next;
107 		device_unregister(dev);
108 		dev = tmp;
109 	}
110 	driver_unregister(&isa_driver->driver);
111 }
112 EXPORT_SYMBOL_GPL(isa_unregister_driver);
113 
114 int isa_register_driver(struct isa_driver *isa_driver, unsigned int ndev)
115 {
116 	int error;
117 	unsigned int id;
118 
119 	isa_driver->driver.bus	= &isa_bus_type;
120 	isa_driver->devices	= NULL;
121 
122 	error = driver_register(&isa_driver->driver);
123 	if (error)
124 		return error;
125 
126 	for (id = 0; id < ndev; id++) {
127 		struct isa_dev *isa_dev;
128 
129 		isa_dev = kzalloc(sizeof *isa_dev, GFP_KERNEL);
130 		if (!isa_dev) {
131 			error = -ENOMEM;
132 			break;
133 		}
134 
135 		isa_dev->dev.parent	= &isa_bus;
136 		isa_dev->dev.bus	= &isa_bus_type;
137 
138 		dev_set_name(&isa_dev->dev, "%s.%u",
139 			     isa_driver->driver.name, id);
140 		isa_dev->dev.platform_data	= isa_driver;
141 		isa_dev->dev.release		= isa_dev_release;
142 		isa_dev->id			= id;
143 
144 		isa_dev->dev.coherent_dma_mask = DMA_24BIT_MASK;
145 		isa_dev->dev.dma_mask = &isa_dev->dev.coherent_dma_mask;
146 
147 		error = device_register(&isa_dev->dev);
148 		if (error) {
149 			put_device(&isa_dev->dev);
150 			break;
151 		}
152 
153 		if (isa_dev->dev.platform_data) {
154 			isa_dev->next = isa_driver->devices;
155 			isa_driver->devices = &isa_dev->dev;
156 		} else
157 			device_unregister(&isa_dev->dev);
158 	}
159 
160 	if (!error && !isa_driver->devices)
161 		error = -ENODEV;
162 
163 	if (error)
164 		isa_unregister_driver(isa_driver);
165 
166 	return error;
167 }
168 EXPORT_SYMBOL_GPL(isa_register_driver);
169 
170 static int __init isa_bus_init(void)
171 {
172 	int error;
173 
174 	error = bus_register(&isa_bus_type);
175 	if (!error) {
176 		error = device_register(&isa_bus);
177 		if (error)
178 			bus_unregister(&isa_bus_type);
179 	}
180 	return error;
181 }
182 
183 device_initcall(isa_bus_init);
184