From c48935ab6b1280a80b38405369e88470f49809f4 Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Wed, 16 Jun 2021 16:15:28 +0200 Subject: drm/dp_helper: Mention the concurrency requirement hw_mutex Drivers that allow concurrent access over multiple DP channels need to provide additional locking, even though the hw_mutex field might indicate otherwise. Clarify it in the documentation. Suggested-by: Daniel Vetter Signed-off-by: Maxime Ripard Acked-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210616141529.630719-2-maxime@cerno.tech --- include/drm/drm_dp_helper.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/drm') diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 683aa9892bad..9336bfbdb389 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -1913,6 +1913,10 @@ struct drm_dp_aux { /** * @hw_mutex: internal mutex used for locking transfers. + * + * Note that if the underlying hardware is shared among multiple + * channels, the driver needs to do additional locking to + * prevent concurrent access. */ struct mutex hw_mutex; -- cgit v1.2.3