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);