标签：style blog color io 使用 ar for strong sp
1922 module_init(netdrv_init_module); 1923 module_exit(netdrv_cleanup_module);module_init/module_exit是两个宏。module_init是该驱动程序的入口，载入驱动模块时，驱动程序就从netdrv_init_module函数開始运行。而当该驱动程序相应的设备被删除了，则会运行netdrv_cleanup_module这个函数。
1906 static int __init netdrv_init_module(void)
1907 {
1908 /* when a module, this is printed whether or not devices are found in probe */
1909 #ifdef MODULE
1910 printk(version);
1911 #endif
1912 return pci_register_driver(&netdrv_pci_driver);
1913 }能够看到，初始化函数非常easy，仅仅运行了一个pci_register_driver函数就返回了。 50 struct bus_type {
51 const char *name;
52 struct bus_attribute *bus_attrs;
53 struct device_attribute *dev_attrs;
54 struct driver_attribute *drv_attrs;
55
56 int (*match)(struct device *dev, struct device_driver *drv);
。。。
68 };设备：406 struct device {
407 struct device *parent;
408
409 struct device_private *p;
410
411 struct kobject kobj;
412 const char *init_name; /* initial name of the device */
413 struct device_type *type;
414
415 struct mutex mutex; /* mutex to synchronize calls to
416 * its driver.
417 */
418
419 struct bus_type *bus; /* type of bus device is on */
420 struct device_driver *driver; /* which driver has allocated this
421 device */
。。。
456
457 void (*release)(struct device *dev);
458 };驱动：122 struct device_driver {
123 const char *name;
124 struct bus_type *bus;
125
126 struct module *owner;
127 const char *mod_name; /* used for built-in modules */
128
129 bool suppress_bind_attrs; /* disables bind/unbind via sysfs */
130
131 #if defined(CONFIG_OF)
132 const struct of_device_id *of_match_table;
133 #endif
134
135 int (*probe) (struct device *dev);
136 int (*remove) (struct device *dev);
。。。
145 };
896 #define pci_register_driver(driver) 897 __pci_register_driver(driver, THIS_MODULE, KBUILD_MODNAME) 1103 int __pci_register_driver(struct pci_driver *drv, struct module *owner, 1104 const char *mod_name)真正的注冊函数式__pci_register_driver()，它的第一个參数是struct pci_driver类型的，再看看这个结构的定义：
542 struct pci_driver {
543 struct list_head node;
544 const char *name;
545 const struct pci_device_id *id_table; /* must be non-NULL for probe to be calle d */
546 int (*probe) (struct pci_dev *dev, const struct pci_device_id *id); /* New de vice inserted */
547 void (*remove) (struct pci_dev *dev); /* Device removed (NULL if not a hot-plug capable driver) */
548 int (*suspend) (struct pci_dev *dev, pm_message_t state); /* Device suspended * /
549 int (*suspend_late) (struct pci_dev *dev, pm_message_t state);
550 int (*resume_early) (struct pci_dev *dev);
551 int (*resume) (struct pci_dev *dev); /* Device woken up */
552 void (*shutdown) (struct pci_dev *dev);
553 struct pci_error_handlers *err_handler;
554 struct device_driver driver;
555 struct pci_dynids dynids;
556 };细致看这个结构，发现其中一个成员是我们上面的总线设备模型中的driver的结构体。事实上在linux内核中，全部设备的驱动的定义，都是以struct device_driver为基类，进行继承与扩展的。你没有看错，内核其中使用了非常多OO的思想。再看看网卡I2C设备的的驱动描写叙述：143 struct i2c_driver {
144 unsigned int class;
145
。。。
174 struct device_driver driver;
175 const struct i2c_device_id *id_table;
176
177 /* Device detection callback for automatic device creation */
178 int (*detect)(struct i2c_client *, struct i2c_board_info *);
179 const unsigned short *address_list;
180 struct list_head clients;
181 };如今我们知道了pci设备的驱动程序的描写叙述方法。可是问题又来了：这么复杂的一个结构体，我们怎么用呢？1894 static struct pci_driver netdrv_pci_driver = {
1895 .name = MODNAME,
1896 .id_table = netdrv_pci_tbl,
1897 .probe = netdrv_init_one,
1898 .remove = __devexit_p(netdrv_remove_one),
1899 #ifdef CONFIG_PM
1900 .suspend = netdrv_suspend,
1901 .resume = netdrv_resume,
1902 #endif /* CONFIG_PM */
1903 };我们能够看出来，并非这个结构体的全部成员我们都要操作，我们仅仅管当中最关键的几个即可了。 221 static DEFINE_PCI_DEVICE_TABLE(netdrv_pci_tbl) = {
222 {0x10ec, 0x8139, PCI_ANY_ID, PCI_ANY_ID, 0, 0, RTL8139 },
223 {0x10ec, 0x8138, PCI_ANY_ID, PCI_ANY_ID, 0, 0, NETDRV_CB },
224 {0x1113, 0x1211, PCI_ANY_ID, PCI_ANY_ID, 0, 0, SMC1211TX },
225 /* {0x1113, 0x1211, PCI_ANY_ID, PCI_ANY_ID, 0, 0, MPX5030 },*/
226 {0x1500, 0x1360, PCI_ANY_ID, PCI_ANY_ID, 0, 0, DELTA8139 },
227 {0x4033, 0x1360, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ADDTRON8139 },
228 {0,}
229 };
230 MODULE_DEVICE_TABLE(pci, netdrv_pci_tbl);这里表示的就是本驱动程序支持的设备类型。1103 int __pci_register_driver(struct pci_driver *drv, struct module *owner,
1104 const char *mod_name)
1105 {
1106 int error;
1107
1108 /* initialize common driver fields */
1109 drv->driver.name = drv->name;
1110 drv->driver.bus = &pci_bus_type;
1111 drv->driver.owner = owner;
1112 drv->driver.mod_name = mod_name;
1113
1114 spin_lock_init(&drv->dynids.lock);
1115 INIT_LIST_HEAD(&drv->dynids.list);
1116
1117 /* register with core */
1118 error = driver_register(&drv->driver);
1119 if (error)
1120 goto out;
1121
。。。。。。。。
1137 }
222 int driver_register(struct device_driver *drv)
223 {
224 int ret;
225 struct device_driver *other;
226
227 BUG_ON(!drv->bus->p);
228
229 if ((drv->bus->probe && drv->probe) ||
230 (drv->bus->remove && drv->remove) ||
231 (drv->bus->shutdown && drv->shutdown))
232 printk(KERN_WARNING "Driver '%s' needs updating - please use "
233 "bus_type methods\n", drv->name);
234
235 other = driver_find(drv->name, drv->bus);
236 if (other) {
237 put_driver(other);
238 printk(KERN_ERR "Error: Driver '%s' is already registered, "
239 "aborting...\n", drv->name);
240 return -EBUSY;
241 }
242
243 ret = bus_add_driver(drv);
244 if (ret)
245 return ret;
246 ret = driver_add_groups(drv, drv->groups);
247 if (ret)
248 bus_remove_driver(drv);
249 return ret;
250 }driver_register中调用bus_add_driver，将设备驱动加入?到总线上。 625 int bus_add_driver(struct device_driver *drv)
626 {
。。。。。。。。。。。。。
642 klist_init(&priv->klist_devices, NULL, NULL);
643 priv->driver = drv;
644 drv->p = priv;
645 priv->kobj.kset = bus->p->drivers_kset;
646 error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL,
647 "%s", drv->name);
648 if (error)
649 goto out_unregister;
650
651 if (drv->bus->p->drivers_autoprobe) {
652 error = driver_attach(drv);
653 if (error)
654 goto out_unregister;
655 }
。。。。。。。。。。。。。。。
690 }
303 int driver_attach(struct device_driver *drv)
304 {
305 return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);
306 } 285 int bus_for_each_dev(struct bus_type *bus, struct device *start,
286 void *data, int (*fn)(struct device *, void *))
287 {
。。。。。。。。。。。。
295 klist_iter_init_node(&bus->p->klist_devices, &i,
296 (start ? &start->p->knode_bus : NULL));
297 while ((dev = next_device(&i)) && !error)
298 <span style="color:#ff0000;">error = fn(dev, data);</span>
299 klist_iter_exit(&i);
300 return error;
301 }这里的fn就是__driver_attach函数，我们来看一下它干了什么：265 static int __driver_attach(struct device *dev, void *data)
266 {
267 struct device_driver *drv = data;
。。。。。。。。。。。。。。。
279 if (!driver_match_device(drv, dev))
280 return 0;
281
282 if (dev->parent) /* Needed for USB */
283 device_lock(dev->parent);
284 device_lock(dev);
285 if (!dev->driver)
286 driver_probe_device(drv, dev);
287 device_unlock(dev);
288 if (dev->parent)
289 device_unlock(dev->parent);
290
291 return 0;
292 }279行的driver_match_device函数就是用来为driver匹配device的
108 static inline int driver_match_device(struct device_driver *drv,
109 struct device *dev)
110 {
111 return drv->bus->match ? drv->bus->match(dev, drv) : 1;
112 }这里開始调用device_driver中注冊的match函数来进行匹配了，匹配的详细过程就不看了。再回到上面的__driver_attach函数的driver_probe_device中。
200 int driver_probe_device(struct device_driver *drv, struct device *dev)
201 {
202 int ret = 0;
203
204 if (!device_is_registered(dev))
205 return -ENODEV;
206
207 pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
208 drv->bus->name, __func__, dev_name(dev), drv->name);
209
210 pm_runtime_get_noresume(dev);
211 pm_runtime_barrier(dev);
212 ret = really_probe(dev, drv);
213 pm_runtime_put_sync(dev);
214
215 return ret;
216 }108 static int really_probe(struct device *dev, struct device_driver *drv)
109 {
110 int ret = 0;
111
112 atomic_inc(&probe_count);
113 pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
114 drv->bus->name, __func__, drv->name, dev_name(dev));
115 WARN_ON(!list_empty(&dev->devres_head));
116
117 dev->driver = drv;
118 if (driver_sysfs_add(dev)) {
119 printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
120 __func__, dev_name(dev));
121 goto probe_failed;
122 }
123
124 if (dev->bus->probe) {
125 ret = dev->bus->probe(dev);
126 if (ret)
127 goto probe_failed;
128 } else if (drv->probe) {
129 ret = drv->probe(dev);
130 if (ret)
131 goto probe_failed;
132 }
133
。。。。。。。。。。。。。。
160 }到这里，最终看到drv->probe函数了。驱动程序的probe函数開始运行了，驱动程序的注冊工作也就大功告成了。
标签：style blog color io 使用 ar for strong sp
原文地址：http://www.cnblogs.com/yxwkf/p/4024178.html
