@@ -122,7 +122,7 @@ static const char *drm_platform_get_name(struct drm_device *dev)
static int drm_platform_set_busid(struct drm_device *dev, struct drm_master *master)
{
- int len, ret;
+ int len, ret, id;
master->unique_len = 13 + strlen(dev->platformdev->name);
master->unique_size = master->unique_len;
@@ -131,8 +131,16 @@ static int drm_platform_set_busid(struct drm_device *dev, struct drm_master *mas
if (master->unique == NULL)
return -ENOMEM;
+ id = dev->platformdev->id;
+
+ /* if only a single instance of the platform device, id will be
+ * set to -1.. use 0 instead to avoid a funny looking bus-id:
+ */
+ if (id == -1)
+ id = 0;
+
len = snprintf(master->unique, master->unique_len,
- "platform:%s:%02d", dev->platformdev->name, dev->platformdev->id);
+ "platform:%s:%02d", dev->platformdev->name, id);
if (len > master->unique_len) {
DRM_ERROR("Unique buffer overflowed\n");