dma-buf: clarify dma_fence_ops->wait documentation

This callback is pretty much deprecated and should not be used by new implementations.

Clarify that in the documentation as well.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210901120240.7339-2-christian.koenig@amd.com

diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h
index 4cc119a..a706b7b 100644 (file)
--- a/include/linux/dma-fence.h
+++ b/include/linux/dma-fence.h
@@ -214,19 +214,15 @@ struct dma_fence_ops {
         * Custom wait implementation, defaults to dma_fence_default_wait() if
         * not set.
         *
-        * The dma_fence_default_wait implementation should work for any fence, as long
-        * as @enable_signaling works correctly. This hook allows drivers to
-        * have an optimized version for the case where a process context is
-        * already available, e.g. if @enable_signaling for the general case
-        * needs to set up a worker thread.
+        * Deprecated and should not be used by new implementations. Only used
+        * by existing implementations which need special handling for their
+        * hardware reset procedure.
         *
         * Must return -ERESTARTSYS if the wait is intr = true and the wait was
         * interrupted, and remaining jiffies if fence has signaled, or 0 if wait
         * timed out. Can also return other error values on custom implementations,
         * which should be treated as if the fence is signaled. For example a hardware
         * lockup could be reported like that.
-        *
-        * This callback is optional.
         */
        signed long (*wait)(struct dma_fence *fence,
                            bool intr, signed long timeout);