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/dma-mapping.h>
  11 #include <linux/isa.h>
  12
  13 static struct device isa_bus = {
  14         .bus_id         = "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                 snprintf(isa_dev->dev.bus_id, BUS_ID_SIZE, "%s.%u",
 139                                 isa_driver->driver.name, id);
 140
 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_24BIT_MASK;
 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
 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 device_initcall(isa_bus_init);