ACPI / scan: Simplify ACPI driver probing

There is no particular reason why acpi_bus_driver_init() needs to be
a separate function and its location with respect to its only caller,
acpi_device_probe(), makes the code a bit difficult to follow.

Besides, it doesn't really make sense to check if 'device' is not
NULL in acpi_bus_driver_init(), because we've already dereferenced
dev->driver in acpi_device_probe() at that point and, moreover,
'device' cannot be NULL then, because acpi_device_probe() is called
via really_probe() (which also sets dev->driver for that matter).

For these reasons, drop acpi_bus_driver_init() altogether and move
the remaining code from it directly into acpi_device_probe().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 27 insertions, 54 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index b14ac46948c9..4eeea2262454 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -816,32 +816,40 @@ static void acpi_device_remove_notify_handler(struct acpi_device *device)
                                            acpi_device_notify);
 }
 
-static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
-static int acpi_device_probe(struct device * dev)
+static int acpi_device_probe(struct device *dev)
 {
         struct acpi_device *acpi_dev = to_acpi_device(dev);
         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
         int ret;
 
-        ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
-        if (!ret) {
-                if (acpi_drv->ops.notify) {
-                        ret = acpi_device_install_notify_handler(acpi_dev);
-                        if (ret) {
-                                if (acpi_drv->ops.remove)
-                                        acpi_drv->ops.remove(acpi_dev);
-                                acpi_dev->driver = NULL;
-                                acpi_dev->driver_data = NULL;
-                                return ret;
-                        }
-                }
+        if (!acpi_drv->ops.add)
+                return -ENOSYS;
 
-                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                        "Found driver [%s] for device [%s]\n",
-                        acpi_drv->name, acpi_dev->pnp.bus_id));
-                get_device(dev);
+        ret = acpi_drv->ops.add(acpi_dev);
+        if (ret)
+                return ret;
+
+        acpi_dev->driver = acpi_drv;
+        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                          "Driver [%s] successfully bound to device [%s]\n",
+                          acpi_drv->name, acpi_dev->pnp.bus_id));
+
+        if (acpi_drv->ops.notify) {
+                ret = acpi_device_install_notify_handler(acpi_dev);
+                if (ret) {
+                        if (acpi_drv->ops.remove)
+                                acpi_drv->ops.remove(acpi_dev);
+
+                        acpi_dev->driver = NULL;
+                        acpi_dev->driver_data = NULL;
+                        return ret;
+                }
         }
-        return ret;
+
+        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
+                          acpi_drv->name, acpi_dev->pnp.bus_id));
+        get_device(dev);
+        return 0;
 }
 
 static int acpi_device_remove(struct device * dev)
@@ -998,41 +1006,6 @@ static void acpi_device_unregister(struct acpi_device *device)
                                  Driver Management
    -------------------------------------------------------------------------- */
 /**
- * acpi_bus_driver_init - add a device to a driver
- * @device: the device to add and initialize
- * @driver: driver for the device
- *
- * Used to initialize a device via its device driver.  Called whenever a
- * driver is bound to a device.  Invokes the driver's add() ops.
- */
-static int
-acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
-{
-        int result = 0;
-
-        if (!device || !driver)
-                return -EINVAL;
-
-        if (!driver->ops.add)
-                return -ENOSYS;
-
-        result = driver->ops.add(device);
-        if (result)
-                return result;
-
-        device->driver = driver;
-
-        /*
-         * TBD - Configuration Management: Assign resources to device based
-         * upon possible configuration and currently allocated resources.
-         */
-
-        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                          "Driver successfully bound to device\n"));
-        return 0;
-}
-
-/**
  * acpi_bus_register_driver - register a driver with the ACPI bus
  * @driver: driver being registered
  *