ACPI: Fix autloading of dock, video, bay and all linux specific HID drivers

References: https://bugzilla.novell.com/show_bug.cgi?id=302482

Due to the new autloading of acpi drivers, the dock driver
wasn't loaded anymore as there is no HID to identify it with
(dock is needed if ACPI has a  _DCK method).
This patch is a workaround for this, original by Thomas Renninger,
revised first by Kay Sievers and last by Frank Seidel.
V2 of this patch fixed problems on systems without a defined _CID for
the docking devices.

Signed-off-by: Thomas Renninger <trenn@novell.com>
Signed-off-by: Kay Sievers <kasievers@novell.com>
Signed-off-by: Frank Seidel <fseidel@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 85 insertions, 15 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 5b4d462117cf..bf079265ce7e 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -941,6 +941,15 @@ static int acpi_bay_match(struct acpi_device *device){
         return -ENODEV;
 }
 
+/*
+ * acpi_dock_match - see if a device has a _DCK method
+ */
+static int acpi_dock_match(struct acpi_device *device)
+{
+        acpi_handle tmp;
+        return acpi_get_handle(device->handle, "_DCK", &tmp);
+}
+
 static void acpi_device_set_id(struct acpi_device *device,
                                struct acpi_device *parent, acpi_handle handle,
                                int type)
@@ -950,6 +959,7 @@ static void acpi_device_set_id(struct acpi_device *device,
         char *hid = NULL;
         char *uid = NULL;
         struct acpi_compatible_id_list *cid_list = NULL;
+        const char *cid_add = NULL;
         acpi_status status;
 
         switch (type) {
@@ -972,15 +982,18 @@ static void acpi_device_set_id(struct acpi_device *device,
                         device->flags.bus_address = 1;
                 }
 
-                if(!(info->valid & (ACPI_VALID_HID | ACPI_VALID_CID))){
-                        status = acpi_video_bus_match(device);
-                        if(ACPI_SUCCESS(status))
-                                hid = ACPI_VIDEO_HID;
+                /* If we have a video/bay/dock device, add our selfdefined
+                   HID to the CID list. Like that the video/bay/dock drivers
+                   will get autoloaded and the device might still match
+                   against another driver.
+                */
+                if (ACPI_SUCCESS(acpi_video_bus_match(device)))
+                        cid_add = ACPI_VIDEO_HID;
+                else if (ACPI_SUCCESS(acpi_bay_match(device)))
+                        cid_add = ACPI_BAY_HID;
+                else if (ACPI_SUCCESS(acpi_dock_match(device)))
+                        cid_add = ACPI_DOCK_HID;
 
-                        status = acpi_bay_match(device);
-                        if (ACPI_SUCCESS(status))
-                                hid = ACPI_BAY_HID;
-                }
                 break;
         case ACPI_BUS_TYPE_POWER:
                 hid = ACPI_POWER_HID;
@@ -1021,11 +1034,44 @@ static void acpi_device_set_id(struct acpi_device *device,
                 strcpy(device->pnp.unique_id, uid);
                 device->flags.unique_id = 1;
         }
-        if (cid_list) {
-                device->pnp.cid_list = kmalloc(cid_list->size, GFP_KERNEL);
-                if (device->pnp.cid_list)
-                        memcpy(device->pnp.cid_list, cid_list, cid_list->size);
-                else
+        if (cid_list || cid_add) {
+                struct  acpi_compatible_id_list *list;
+                int size = 0;
+                int count = 0;
+
+                if (cid_list) {
+                        size = cid_list->size;
+                } else if (cid_add) {
+                        size = sizeof(struct acpi_compatible_id_list);
+                        cid_list = ACPI_ALLOCATE_ZEROED((acpi_size) size);
+                        if (!cid_list) {
+                                printk(KERN_ERR "Memory allocation error\n");
+                                kfree(buffer.pointer);
+                                return;
+                        } else {
+                                cid_list->count = 0;
+                                cid_list->size = size;
+                        }
+                }
+                if (cid_add)
+                        size += sizeof(struct acpi_compatible_id);
+                list = kmalloc(size, GFP_KERNEL);
+
+                if (list) {
+                        if (cid_list) {
+                                memcpy(list, cid_list, cid_list->size);
+                                count = cid_list->count;
+                        }
+                        if (cid_add) {
+                                strncpy(list->id[count].value, cid_add,
+                                        ACPI_MAX_CID_LENGTH);
+                                count++;
+                                device->flags.compatible_ids = 1;
+                        }
+                        list->size = size;
+                        list->count = count;
+                        device->pnp.cid_list = list;
+                } else
                         printk(KERN_ERR "Memory allocation error\n");
         }
 
@@ -1081,6 +1127,20 @@ static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
 }
 
 static int
+acpi_is_child_device(struct acpi_device *device,
+                        int (*matcher)(struct acpi_device *))
+{
+        int result = -ENODEV;
+
+        do {
+                if (ACPI_SUCCESS(matcher(device)))
+                        return AE_OK;
+        } while ((device = device->parent));
+
+        return result;
+}
+
+static int
 acpi_add_single_object(struct acpi_device **child,
                        struct acpi_device *parent, acpi_handle handle, int type,
                         struct acpi_bus_ops *ops)
@@ -1131,10 +1191,20 @@ acpi_add_single_object(struct acpi_device **child,
         case ACPI_BUS_TYPE_PROCESSOR:
         case ACPI_BUS_TYPE_DEVICE:
                 result = acpi_bus_get_status(device);
-                if (ACPI_FAILURE(result) || !device->status.present) {
-                        result = -ENOENT;
+                if (ACPI_FAILURE(result)) {
+                        result = -ENODEV;
                         goto end;
                 }
+                if (!device->status.present) {
+                        /* Bay and dock should be handled even if absent */
+                        if (!ACPI_SUCCESS(
+                             acpi_is_child_device(device, acpi_bay_match)) &&
+                            !ACPI_SUCCESS(
+                             acpi_is_child_device(device, acpi_dock_match))) {
+                                        result = -ENODEV;
+                                        goto end;
+                        }
+                }
                 break;
         default:
                 STRUCT_TO_INT(device->status) =