ACPI: Add a docked sysfs file to the dock driver.  

Warning: Compile tested only

Signed-off-by: Brandon Philips <brandon@ifup.org>
---
 drivers/acpi/dock.c |   50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

Index: linux-2.6-rc/drivers/acpi/dock.c
===================================================================
--- linux-2.6-rc.orig/drivers/acpi/dock.c
+++ linux-2.6-rc/drivers/acpi/dock.c
@@ -603,6 +603,36 @@ find_dock_devices(acpi_handle handle, u3
 	return AE_OK;
 }
 
+#define ACPI_DEVICE_ATTR(_name,_mode,_show,_store) \
+static struct acpi_device_attribute acpi_device_attr_##_name = \
+		__ATTR(_name, _mode, _show, _store)
+/*
+ * show_docked - read method for "docked" file in sysfs
+ */
+static ssize_t show_docked(struct acpi_device *dev, char *buf)
+{
+	struct dock_station *ds = (struct dock_station *)dev->driver_data;
+	return snprintf(buf, PAGE_SIZE, "%d\n", dock_present(ds));
+
+}
+ACPI_DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);
+
+static void dock_remove_sysfs_files(struct acpi_device *ad)
+{
+	sysfs_remove_file(&ad->kobj, &acpi_device_attr_docked.attr);
+}
+
+static int dock_add_sysfs_files(struct acpi_device *ad)
+{
+	int ret;
+
+	ret = sysfs_create_file(&ad->kobj, &acpi_device_attr_docked.attr);
+	if (ret)
+		dock_remove_sysfs_files(ad);;
+
+	return ret;
+}
+
 /**
  * dock_add - add a new dock station
  * @handle: the dock station handle
@@ -615,6 +645,7 @@ static int dock_add(acpi_handle handle)
 	int ret;
 	acpi_status status;
 	struct dock_dependent_device *dd;
+	struct acpi_device *ad;
 
 	/* allocate & initialize the dock_station private data */
 	dock_station = kzalloc(sizeof(*dock_station), GFP_KERNEL);
@@ -652,6 +683,14 @@ static int dock_add(acpi_handle handle)
 		goto dock_add_err;
 	}
 
+	if ((ret = acpi_bus_get_device(handle, &ad)))
+		goto dock_add_err;
+
+	ad->driver_data = (void *)dock_station;
+
+	if (dock_add_sysfs_files(ad))
+		printk(KERN_ERR PREFIX "Unable to create sysfs files\n");
+
 	printk(KERN_INFO PREFIX "%s \n", ACPI_DOCK_DRIVER_NAME);
 
 	return 0;
@@ -669,6 +708,8 @@ static int dock_remove(void)
 {
 	struct dock_dependent_device *dd, *tmp;
 	acpi_status status;
+	struct acpi_device *ad;
+	int ret;
 
 	if (!dock_station)
 		return 0;
@@ -685,6 +726,15 @@ static int dock_remove(void)
 	if (ACPI_FAILURE(status))
 		printk(KERN_ERR "Error removing notify handler\n");
 
+	ret = acpi_bus_get_device(dock_station->handle, &ad);
+	if  (ret < 0) {
+		printk(KERN_ERR "Error getting docking station\n");
+		goto error;
+	}
+
+	dock_remove_sysfs_files(ad);
+
+error:
 	/* free dock station memory */
 	kfree(dock_station);
 	return 0;