ACPI: work around duplicate name "VID" problem on T61

This can only fix the problem that more than one video bus device
have the same AML name "VID".
ie. the proc I/F for the second "VID" video bus device is located under
/proc/acpi/video/VID1/...

As this is really rare and the ACPI proc I/F is a legacy feature that
we are planning to remove.
We won't provide a generic solution for this problem.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index d987019..ac63be4 100644 (file)
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -1833,6 +1833,7 @@ static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
        return;
 }
 
+static int instance;
 static int acpi_video_bus_add(struct acpi_device *device)
 {
        int result = 0;
@@ -1847,6 +1848,13 @@ static int acpi_video_bus_add(struct acpi_device *device)
        if (!video)
                return -ENOMEM;
 
+       /* a hack to fix the duplicate name "VID" problem on T61 */
+       if (!strcmp(device->pnp.bus_id, "VID")) {
+               if (instance)
+                       device->pnp.bus_id[3] = '0' + instance;
+               instance ++;
+       }
+
        video->device = device;
        strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
        strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);