#include <linux/device.h>
#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/wait.h>
#include "base.h"
#include "power/power.h"
#define to_drv(node) container_of(node, struct device_driver, kobj.entry)
+static void driver_bound(struct device *dev)
+{
+ if (klist_node_attached(&dev->knode_driver)) {
+ printk(KERN_WARNING "%s: device %s already bound\n",
+ __FUNCTION__, kobject_name(&dev->kobj));
+ return;
+ }
+
+ pr_debug("bound device '%s' to driver '%s'\n",
+ dev->bus_id, dev->driver->name);
+
+ if (dev->bus)
+ blocking_notifier_call_chain(&dev->bus->bus_notifier,
+ BUS_NOTIFY_BOUND_DRIVER, dev);
+
+ klist_add_tail(&dev->knode_driver, &dev->driver->klist_devices);
+}
+
+static int driver_sysfs_add(struct device *dev)
+{
+ int ret;
+
+ ret = sysfs_create_link(&dev->driver->kobj, &dev->kobj,
+ kobject_name(&dev->kobj));
+ 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;
+}
+
+static void driver_sysfs_remove(struct device *dev)
+{
+ struct device_driver *drv = dev->driver;
+
+ if (drv) {
+ sysfs_remove_link(&drv->kobj, kobject_name(&dev->kobj));
+ sysfs_remove_link(&dev->kobj, "driver");
+ }
+}
+
/**
* device_bind_driver - bind a driver to one device.
* @dev: device.
*
* This function must be called with @dev->sem held.
*/
-void device_bind_driver(struct device * dev)
+int device_bind_driver(struct device *dev)
{
- 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,
- kobject_name(&dev->kobj));
- sysfs_create_link(&dev->kobj, &dev->driver->kobj, "driver");
+ int ret;
+
+ ret = driver_sysfs_add(dev);
+ if (!ret)
+ driver_bound(dev);
+ 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.
- */
-int driver_probe_device(struct device_driver * drv, struct device * dev)
+static atomic_t probe_count = ATOMIC_INIT(0);
+static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue);
+
+static int really_probe(struct device *dev, struct device_driver *drv)
{
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);
+ WARN_ON(!list_empty(&dev->devres_head));
- pr_debug("%s: Matched Device %s with Driver %s\n",
- drv->bus->name, dev->bus_id, drv->name);
dev->driver = drv;
- if (drv->probe) {
+ if (driver_sysfs_add(dev)) {
+ printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
+ __FUNCTION__, dev->bus_id);
+ goto probe_failed;
+ }
+
+ if (dev->bus->probe) {
+ ret = dev->bus->probe(dev);
+ if (ret)
+ goto probe_failed;
+ } else if (drv->probe) {
ret = drv->probe(dev);
- if (ret) {
- dev->driver = NULL;
- goto ProbeFailed;
- }
+ if (ret)
+ goto probe_failed;
}
- device_bind_driver(dev);
+
+ driver_bound(dev);
ret = 1;
pr_debug("%s: Bound Device %s to Driver %s\n",
drv->bus->name, dev->bus_id, drv->name);
- goto Done;
-
- ProbeFailed:
- if (ret == -ENODEV || ret == -ENXIO) {
- /* Driver matched, but didn't support device
- * or device not found.
- * Not an error; keep going.
- */
- ret = 0;
- } else {
+ goto done;
+
+probe_failed:
+ devres_release_all(dev);
+ driver_sysfs_remove(dev);
+ dev->driver = NULL;
+
+ if (ret != -ENODEV && ret != -ENXIO) {
/* driver matched but the probe failed */
printk(KERN_WARNING
"%s: probe of %s failed with error %d\n",
drv->name, dev->bus_id, ret);
}
- Done:
+ /*
+ * Ignore errors returned by ->probe so that the next driver can try
+ * its luck.
+ */
+ ret = 0;
+done:
+ atomic_dec(&probe_count);
+ wake_up(&probe_waitqueue);
+ 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, -ENODEV if the device is
+ * not registered, 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)
+{
+ 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);
+
+ ret = really_probe(dev, drv);
+
+done:
return ret;
}
* pair is found, break out and return.
*
* Returns 1 if the device was bound to a driver;
- * 0 if no matching device was found; error code otherwise.
+ * 0 if no matching device was found;
+ * -ENODEV if the device is not registered.
+ *
+ * When called for a USB interface, @dev->parent->sem must be held.
*/
int device_attach(struct device * dev)
{
down(&dev->sem);
if (dev->driver) {
- device_bind_driver(dev);
- ret = 1;
- } else
+ ret = device_bind_driver(dev);
+ if (ret == 0)
+ ret = 1;
+ else {
+ dev->driver = NULL;
+ ret = 0;
+ }
+ } else {
ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach);
+ }
up(&dev->sem);
return ret;
}
* is an error.
*/
+ if (dev->parent) /* Needed for USB */
+ down(&dev->parent->sem);
down(&dev->sem);
if (!dev->driver)
driver_probe_device(drv, dev);
up(&dev->sem);
-
+ if (dev->parent)
+ up(&dev->parent->sem);
return 0;
}
* 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);
}
-/**
- * device_release_driver - manually detach device from driver.
- * @dev: device.
- *
- * Manually detach device from driver.
- *
+/*
* __device_release_driver() must be called with @dev->sem held.
+ * When called for a USB interface, @dev->parent->sem must be held as well.
*/
-
static void __device_release_driver(struct device * dev)
{
struct device_driver * drv;
- drv = dev->driver;
+ drv = get_driver(dev->driver);
if (drv) {
- get_driver(drv);
- sysfs_remove_link(&drv->kobj, kobject_name(&dev->kobj));
+ driver_sysfs_remove(dev);
sysfs_remove_link(&dev->kobj, "driver");
klist_remove(&dev->knode_driver);
- if (drv->remove)
+ if (dev->bus)
+ blocking_notifier_call_chain(&dev->bus->bus_notifier,
+ BUS_NOTIFY_UNBIND_DRIVER,
+ dev);
+
+ if (dev->bus && dev->bus->remove)
+ dev->bus->remove(dev);
+ else if (drv->remove)
drv->remove(dev);
+ devres_release_all(dev);
dev->driver = NULL;
put_driver(drv);
}
}
+/**
+ * device_release_driver - manually detach device from driver.
+ * @dev: device.
+ *
+ * Manually detach device from driver.
+ * When called for a USB interface, @dev->parent->sem must be held.
+ */
void device_release_driver(struct device * dev)
{
/*
struct device * dev;
for (;;) {
- spin_lock_irq(&drv->klist_devices.k_lock);
+ spin_lock(&drv->klist_devices.k_lock);
if (list_empty(&drv->klist_devices.k_list)) {
- spin_unlock_irq(&drv->klist_devices.k_lock);
+ spin_unlock(&drv->klist_devices.k_lock);
break;
}
dev = list_entry(drv->klist_devices.k_list.prev,
struct device, knode_driver.n_node);
get_device(dev);
- spin_unlock_irq(&drv->klist_devices.k_lock);
+ spin_unlock(&drv->klist_devices.k_lock);
+ if (dev->parent) /* Needed for USB */
+ down(&dev->parent->sem);
down(&dev->sem);
if (dev->driver == drv)
__device_release_driver(dev);
up(&dev->sem);
+ if (dev->parent)
+ up(&dev->parent->sem);
put_device(dev);
}
}
-
EXPORT_SYMBOL_GPL(device_bind_driver);
EXPORT_SYMBOL_GPL(device_release_driver);
EXPORT_SYMBOL_GPL(device_attach);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff