drm/ttm: enable TTM page pool kerneldoc

Fix the remaining warnings and finally enable this.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210908132933.3269-9-christian.koenig@amd.com
diff --git a/Documentation/gpu/drm-mm.rst b/Documentation/gpu/drm-mm.rst
index 69c4a20..e053808 100644
--- a/Documentation/gpu/drm-mm.rst
+++ b/Documentation/gpu/drm-mm.rst
@@ -67,6 +67,15 @@
 .. kernel-doc:: drivers/gpu/drm/ttm/ttm_tt.c
    :export:
 
+TTM page pool reference
+-----------------------
+
+.. kernel-doc:: include/drm/ttm/ttm_pool.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/ttm/ttm_pool.c
+   :export:
+
 The Graphics Execution Manager (GEM)
 ====================================
 
diff --git a/include/drm/ttm/ttm_pool.h b/include/drm/ttm/ttm_pool.h
index 4321728..ef09b23 100644
--- a/include/drm/ttm/ttm_pool.h
+++ b/include/drm/ttm/ttm_pool.h
@@ -37,7 +37,7 @@ struct ttm_pool;
 struct ttm_operation_ctx;
 
 /**
- * ttm_pool_type - Pool for a certain memory type
+ * struct ttm_pool_type - Pool for a certain memory type
  *
  * @pool: the pool we belong to, might be NULL for the global ones
  * @order: the allocation order our pages have
@@ -58,8 +58,9 @@ struct ttm_pool_type {
 };
 
 /**
- * ttm_pool - Pool for all caching and orders
+ * struct ttm_pool - Pool for all caching and orders
  *
+ * @dev: the device we allocate pages for
  * @use_dma_alloc: if coherent DMA allocations should be used
  * @use_dma32: if GFP_DMA32 should be used
  * @caching: pools for each caching/order