Add explicit zeroing to "envp" array in device 'show' method
[linux-2.6] / drivers / base / isa.c
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/isa.h>
11
12 static struct device isa_bus = {
13         .bus_id         = "isa"
14 };
15
16 struct isa_dev {
17         struct device dev;
18         struct device *next;
19         unsigned int id;
20 };
21
22 #define to_isa_dev(x) container_of((x), struct isa_dev, dev)
23
24 static int isa_bus_match(struct device *dev, struct device_driver *driver)
25 {
26         struct isa_driver *isa_driver = to_isa_driver(driver);
27
28         if (dev->platform_data == isa_driver) {
29                 if (!isa_driver->match ||
30                         isa_driver->match(dev, to_isa_dev(dev)->id))
31                         return 1;
32                 dev->platform_data = NULL;
33         }
34         return 0;
35 }
36
37 static int isa_bus_probe(struct device *dev)
38 {
39         struct isa_driver *isa_driver = dev->platform_data;
40
41         if (isa_driver->probe)
42                 return isa_driver->probe(dev, to_isa_dev(dev)->id);
43
44         return 0;
45 }
46
47 static int isa_bus_remove(struct device *dev)
48 {
49         struct isa_driver *isa_driver = dev->platform_data;
50
51         if (isa_driver->remove)
52                 return isa_driver->remove(dev, to_isa_dev(dev)->id);
53
54         return 0;
55 }
56
57 static void isa_bus_shutdown(struct device *dev)
58 {
59         struct isa_driver *isa_driver = dev->platform_data;
60
61         if (isa_driver->shutdown)
62                 isa_driver->shutdown(dev, to_isa_dev(dev)->id);
63 }
64
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->suspend)
70                 return isa_driver->suspend(dev, to_isa_dev(dev)->id, state);
71
72         return 0;
73 }
74
75 static int isa_bus_resume(struct device *dev)
76 {
77         struct isa_driver *isa_driver = dev->platform_data;
78
79         if (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
95 static void isa_dev_release(struct device *dev)
96 {
97         kfree(to_isa_dev(dev));
98 }
99
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
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                 snprintf(isa_dev->dev.bus_id, BUS_ID_SIZE, "%s.%u",
138                                 isa_driver->driver.name, id);
139
140                 isa_dev->dev.platform_data      = isa_driver;
141                 isa_dev->dev.release            = isa_dev_release;
142                 isa_dev->id                     = id;
143
144                 error = device_register(&isa_dev->dev);
145                 if (error) {
146                         put_device(&isa_dev->dev);
147                         break;
148                 }
149
150                 if (isa_dev->dev.platform_data) {
151                         isa_dev->next = isa_driver->devices;
152                         isa_driver->devices = &isa_dev->dev;
153                 } else
154                         device_unregister(&isa_dev->dev);
155         }
156
157         if (!error && !isa_driver->devices)
158                 error = -ENODEV;
159
160         if (error)
161                 isa_unregister_driver(isa_driver);
162
163         return error;
164 }
165 EXPORT_SYMBOL_GPL(isa_register_driver);
166
167 static int __init isa_bus_init(void)
168 {
169         int error;
170
171         error = bus_register(&isa_bus_type);
172         if (!error) {
173                 error = device_register(&isa_bus);
174                 if (error)
175                         bus_unregister(&isa_bus_type);
176         }
177         return error;
178 }
179
180 device_initcall(isa_bus_init);