]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/base/dd.c
Merge branch 'intelfb-patches' of master.kernel.org:/pub/scm/linux/kernel/git/airlied...
[linux-2.6-omap-h63xx.git] / drivers / base / dd.c
index 889c71111239436d1c9f705cfa5f32ff14ba6f0f..b5f43c3e44fa2a5c9d5bf23898ea57472e7b38ae 100644 (file)
@@ -17,6 +17,7 @@
 
 #include <linux/device.h>
 #include <linux/module.h>
+#include <linux/kthread.h>
 
 #include "base.h"
 #include "power/power.h"
  *
  *     This function must be called with @dev->sem held.
  */
-void device_bind_driver(struct device * dev)
+int device_bind_driver(struct device *dev)
 {
-       if (klist_node_attached(&dev->knode_driver))
-               return;
+       int ret;
+
+       if (klist_node_attached(&dev->knode_driver)) {
+               printk(KERN_WARNING "%s: device %s already bound\n",
+                       __FUNCTION__, kobject_name(&dev->kobj));
+               return 0;
+       }
 
        pr_debug("bound device '%s' to driver '%s'\n",
                 dev->bus_id, dev->driver->name);
        klist_add_tail(&dev->knode_driver, &dev->driver->klist_devices);
-       sysfs_create_link(&dev->driver->kobj, &dev->kobj,
+       ret = sysfs_create_link(&dev->driver->kobj, &dev->kobj,
                          kobject_name(&dev->kobj));
-       sysfs_create_link(&dev->kobj, &dev->driver->kobj, "driver");
+       if (ret == 0) {
+               ret = sysfs_create_link(&dev->kobj, &dev->driver->kobj,
+                                       "driver");
+               if (ret)
+                       sysfs_remove_link(&dev->driver->kobj,
+                                       kobject_name(&dev->kobj));
+       }
+       return ret;
 }
 
-/**
- *     driver_probe_device - attempt to bind device & driver.
- *     @drv:   driver.
- *     @dev:   device.
- *
- *     First, we call the bus's match function, if one present, which
- *     should compare the device IDs the driver supports with the
- *     device IDs of the device. Note we don't do this ourselves
- *     because we don't know the format of the ID structures, nor what
- *     is to be considered a match and what is not.
- *
- *     This function returns 1 if a match is found, an error if one
- *     occurs (that is not -ENODEV or -ENXIO), and 0 otherwise.
- *
- *     This function must be called with @dev->sem held.  When called
- *     for a USB interface, @dev->parent->sem must be held as well.
- */
-int driver_probe_device(struct device_driver * drv, struct device * dev)
+struct stupid_thread_structure {
+       struct device_driver *drv;
+       struct device *dev;
+};
+
+static atomic_t probe_count = ATOMIC_INIT(0);
+static int really_probe(void *void_data)
 {
+       struct stupid_thread_structure *data = void_data;
+       struct device_driver *drv = data->drv;
+       struct device *dev = data->dev;
        int ret = 0;
 
-       if (drv->bus->match && !drv->bus->match(dev, drv))
-               goto Done;
+       atomic_inc(&probe_count);
+       pr_debug("%s: Probing driver %s with device %s\n",
+                drv->bus->name, drv->name, dev->bus_id);
 
-       pr_debug("%s: Matched Device %s with Driver %s\n",
-                drv->bus->name, dev->bus_id, drv->name);
        dev->driver = drv;
        if (dev->bus->probe) {
                ret = dev->bus->probe(dev);
                if (ret) {
                        dev->driver = NULL;
-                       goto ProbeFailed;
+                       goto probe_failed;
                }
        } else if (drv->probe) {
                ret = drv->probe(dev);
                if (ret) {
                        dev->driver = NULL;
-                       goto ProbeFailed;
+                       goto probe_failed;
                }
        }
-       device_bind_driver(dev);
+       if (device_bind_driver(dev)) {
+               printk(KERN_ERR "%s: device_bind_driver(%s) failed\n",
+                       __FUNCTION__, dev->bus_id);
+               /* How does undo a ->probe?  We're screwed. */
+       }
        ret = 1;
        pr_debug("%s: Bound Device %s to Driver %s\n",
                 drv->bus->name, dev->bus_id, drv->name);
-       goto Done;
+       goto done;
 
- ProbeFailed:
+probe_failed:
        if (ret == -ENODEV || ret == -ENXIO) {
                /* Driver matched, but didn't support device
                 * or device not found.
@@ -110,7 +118,71 @@ int driver_probe_device(struct device_driver * drv, struct device * dev)
                       "%s: probe of %s failed with error %d\n",
                       drv->name, dev->bus_id, ret);
        }
- Done:
+done:
+       kfree(data);
+       atomic_dec(&probe_count);
+       return ret;
+}
+
+/**
+ * driver_probe_done
+ * Determine if the probe sequence is finished or not.
+ *
+ * Should somehow figure out how to use a semaphore, not an atomic variable...
+ */
+int driver_probe_done(void)
+{
+       pr_debug("%s: probe_count = %d\n", __FUNCTION__,
+                atomic_read(&probe_count));
+       if (atomic_read(&probe_count))
+               return -EBUSY;
+       return 0;
+}
+
+/**
+ * driver_probe_device - attempt to bind device & driver together
+ * @drv: driver to bind a device to
+ * @dev: device to try to bind to the driver
+ *
+ * First, we call the bus's match function, if one present, which should
+ * compare the device IDs the driver supports with the device IDs of the
+ * device. Note we don't do this ourselves because we don't know the
+ * format of the ID structures, nor what is to be considered a match and
+ * what is not.
+ *
+ * This function returns 1 if a match is found, an error if one occurs
+ * (that is not -ENODEV or -ENXIO), and 0 otherwise.
+ *
+ * This function must be called with @dev->sem held.  When called for a
+ * USB interface, @dev->parent->sem must be held as well.
+ */
+int driver_probe_device(struct device_driver * drv, struct device * dev)
+{
+       struct stupid_thread_structure *data;
+       struct task_struct *probe_task;
+       int ret = 0;
+
+       if (!device_is_registered(dev))
+               return -ENODEV;
+       if (drv->bus->match && !drv->bus->match(dev, drv))
+               goto done;
+
+       pr_debug("%s: Matched Device %s with Driver %s\n",
+                drv->bus->name, dev->bus_id, drv->name);
+
+       data = kmalloc(sizeof(*data), GFP_KERNEL);
+       data->drv = drv;
+       data->dev = dev;
+
+       if (drv->multithread_probe) {
+               probe_task = kthread_run(really_probe, data,
+                                        "probe-%s", dev->bus_id);
+               if (IS_ERR(probe_task))
+                       ret = PTR_ERR(probe_task);
+       } else
+               ret = really_probe(data);
+
+done:
        return ret;
 }
 
@@ -139,8 +211,9 @@ int device_attach(struct device * dev)
 
        down(&dev->sem);
        if (dev->driver) {
-               device_bind_driver(dev);
-               ret = 1;
+               ret = device_bind_driver(dev);
+               if (ret == 0)
+                       ret = 1;
        } else
                ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach);
        up(&dev->sem);
@@ -182,9 +255,9 @@ static int __driver_attach(struct device * dev, void * data)
  *     returns 0 and the @dev->driver is set, we've found a
  *     compatible pair.
  */
-void driver_attach(struct device_driver * drv)
+int driver_attach(struct device_driver * drv)
 {
-       bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);
+       return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);
 }
 
 /**