1 files changed, 110 insertions, 21 deletions

diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c
index bf5b79ed3613..215f5b30a1f1 100644
--- a/drivers/acpi/dock.c
+++ b/drivers/acpi/dock.c
@@ -27,6 +27,7 @@
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/notifier.h>
+#include <linux/platform_device.h>
 #include <linux/jiffies.h>
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
@@ -39,6 +40,8 @@ MODULE_DESCRIPTION(ACPI_DOCK_DRIVER_NAME);
 MODULE_LICENSE("GPL");
 
 static struct atomic_notifier_head dock_notifier_list;
+static struct platform_device dock_device;
+static char dock_device_name[] = "dock";
 
 struct dock_station {
         acpi_handle handle;
@@ -323,10 +326,12 @@ static void hotplug_dock_devices(struct dock_station *ds, u32 event)
 
 static void dock_event(struct dock_station *ds, u32 event, int num)
 {
+        struct device *dev = &dock_device.dev;
         /*
-         * we don't do events until someone tells me that
-         * they would like to have them.
+         * Indicate that the status of the dock station has
+         * changed.
          */
+        kobject_uevent(&dev->kobj, KOBJ_CHANGE);
 }
 
 /**
@@ -441,6 +446,9 @@ static int dock_in_progress(struct dock_station *ds)
  */
 int register_dock_notifier(struct notifier_block *nb)
 {
+        if (!dock_station)
+                return -ENODEV;
+
         return atomic_notifier_chain_register(&dock_notifier_list, nb);
 }
 
@@ -452,6 +460,9 @@ EXPORT_SYMBOL_GPL(register_dock_notifier);
  */
 void unregister_dock_notifier(struct notifier_block *nb)
 {
+        if (!dock_station)
+                return;
+
         atomic_notifier_chain_unregister(&dock_notifier_list, nb);
 }
 
@@ -512,6 +523,37 @@ void unregister_hotplug_dock_device(acpi_handle handle)
 EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device);
 
 /**
+ * handle_eject_request - handle an undock request checking for error conditions
+ *
+ * Check to make sure the dock device is still present, then undock and
+ * hotremove all the devices that may need removing.
+ */
+static int handle_eject_request(struct dock_station *ds, u32 event)
+{
+        if (!dock_present(ds))
+                return -ENODEV;
+
+        if (dock_in_progress(ds))
+                return -EBUSY;
+
+        /*
+         * here we need to generate the undock
+         * event prior to actually doing the undock
+         * so that the device struct still exists.
+         */
+        dock_event(ds, event, UNDOCK_EVENT);
+        hotplug_dock_devices(ds, ACPI_NOTIFY_EJECT_REQUEST);
+        undock(ds);
+        eject_dock(ds);
+        if (dock_present(ds)) {
+                printk(KERN_ERR PREFIX "Unable to undock!\n");
+                return -EBUSY;
+        }
+
+        return 0;
+}
+
+/**
  * dock_notify - act upon an acpi dock notification
  * @handle: the dock station handle
  * @event: the acpi event
@@ -519,9 +561,7 @@ EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device);
  *
  * If we are notified to dock, then check to see if the dock is
  * present and then dock.  Notify all drivers of the dock event,
- * and then hotplug and devices that may need hotplugging.  For undock
- * check to make sure the dock device is still present, then undock
- * and hotremove all the devices that may need removing.
+ * and then hotplug and devices that may need hotplugging.
  */
 static void dock_notify(acpi_handle handle, u32 event, void *data)
 {
@@ -553,19 +593,7 @@ static void dock_notify(acpi_handle handle, u32 event, void *data)
          * to the driver who wish to hotplug.
          */
         case ACPI_NOTIFY_EJECT_REQUEST:
-                if (!dock_in_progress(ds) && dock_present(ds)) {
-                        /*
-                         * here we need to generate the undock
-                         * event prior to actually doing the undock
-                         * so that the device struct still exists.
-                         */
-                        dock_event(ds, event, UNDOCK_EVENT);
-                        hotplug_dock_devices(ds, ACPI_NOTIFY_EJECT_REQUEST);
-                        undock(ds);
-                        eject_dock(ds);
-                        if (dock_present(ds))
-                                printk(KERN_ERR PREFIX "Unable to undock!\n");
-                }
+                handle_eject_request(ds, event);
                 break;
         default:
                 printk(KERN_ERR PREFIX "Unknown dock event %d\n", event);
@@ -604,6 +632,33 @@ find_dock_devices(acpi_handle handle, u32 lvl, void *context, void **rv)
         return AE_OK;
 }
 
+/*
+ * show_docked - read method for "docked" file in sysfs
+ */
+static ssize_t show_docked(struct device *dev,
+                           struct device_attribute *attr, char *buf)
+{
+        return snprintf(buf, PAGE_SIZE, "%d\n", dock_present(dock_station));
+
+}
+DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);
+
+/*
+ * write_undock - write method for "undock" file in sysfs
+ */
+static ssize_t write_undock(struct device *dev, struct device_attribute *attr,
+                           const char *buf, size_t count)
+{
+        int ret;
+
+        if (!count)
+                return -EINVAL;
+
+        ret = handle_eject_request(dock_station, ACPI_NOTIFY_EJECT_REQUEST);
+        return ret ? ret: count;
+}
+DEVICE_ATTR(undock, S_IWUSR, NULL, write_undock);
+
 /**
  * dock_add - add a new dock station
  * @handle: the dock station handle
@@ -629,6 +684,30 @@ static int dock_add(acpi_handle handle)
         spin_lock_init(&dock_station->hp_lock);
         ATOMIC_INIT_NOTIFIER_HEAD(&dock_notifier_list);
 
+        /* initialize platform device stuff */
+        dock_device.name = dock_device_name;
+        ret = platform_device_register(&dock_device);
+        if (ret) {
+                printk(KERN_ERR PREFIX "Error %d registering dock device\n", ret);
+                kfree(dock_station);
+                return ret;
+        }
+        ret = device_create_file(&dock_device.dev, &dev_attr_docked);
+        if (ret) {
+                printk("Error %d adding sysfs file\n", ret);
+                platform_device_unregister(&dock_device);
+                kfree(dock_station);
+                return ret;
+        }
+        ret = device_create_file(&dock_device.dev, &dev_attr_undock);
+        if (ret) {
+                printk("Error %d adding sysfs file\n", ret);
+                device_remove_file(&dock_device.dev, &dev_attr_docked);
+                platform_device_unregister(&dock_device);
+                kfree(dock_station);
+                return ret;
+        }
+
         /* Find dependent devices */
         acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
                             ACPI_UINT32_MAX, find_dock_devices, dock_station,
@@ -638,7 +717,8 @@ static int dock_add(acpi_handle handle)
         dd = alloc_dock_dependent_device(handle);
         if (!dd) {
                 kfree(dock_station);
-                return -ENOMEM;
+                ret = -ENOMEM;
+                goto dock_add_err_unregister;
         }
         add_dock_dependent_device(dock_station, dd);
 
@@ -658,8 +738,12 @@ static int dock_add(acpi_handle handle)
         return 0;
 
 dock_add_err:
-        kfree(dock_station);
         kfree(dd);
+dock_add_err_unregister:
+        device_remove_file(&dock_device.dev, &dev_attr_docked);
+        device_remove_file(&dock_device.dev, &dev_attr_undock);
+        platform_device_unregister(&dock_device);
+        kfree(dock_station);
         return ret;
 }
 
@@ -686,6 +770,11 @@ static int dock_remove(void)
         if (ACPI_FAILURE(status))
                 printk(KERN_ERR "Error removing notify handler\n");
 
+        /* cleanup sysfs */
+        device_remove_file(&dock_device.dev, &dev_attr_docked);
+        device_remove_file(&dock_device.dev, &dev_attr_undock);
+        platform_device_unregister(&dock_device);
+
         /* free dock station memory */
         kfree(dock_station);
         return 0;
@@ -726,7 +815,7 @@ static int __init dock_init(void)
                             ACPI_UINT32_MAX, find_dock, &num, NULL);
 
         if (!num)
-                return -ENODEV;
+                printk(KERN_INFO "No dock devices found.\n");
 
         return 0;
 }