From b86d895524ab7281da8ca788e3666ab622fc8620 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Mon, 6 Jan 2020 15:34:08 +0100 Subject: drm/bridge: Add an ->atomic_check() hook So that bridge drivers have a way to check/reject an atomic operation. The drm_atomic_bridge_chain_check() (which is just a wrapper around the ->atomic_check() hook) is called in place of drm_bridge_chain_mode_fixup() (when ->atomic_check() is not implemented, the core falls back on ->mode_fixup(), so the behavior should stay the same for existing bridge drivers). Signed-off-by: Boris Brezillon Reviewed-by: Neil Armstrong Reviewed-by: Laurent Pinchart Signed-off-by: Neil Armstrong Reviewed by: Jernej Skrabec Tested-by: Jonas Karlman Link: https://patchwork.freedesktop.org/patch/msgid/20200106143409.32321-4-narmstrong@baylibre.com --- drivers/gpu/drm/drm_bridge.c | 62 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) (limited to 'drivers/gpu/drm/drm_bridge.c') diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 872e159fcb42..8e4b799150b0 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -645,6 +645,68 @@ void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge, } EXPORT_SYMBOL(drm_atomic_bridge_chain_enable); +static int drm_atomic_bridge_check(struct drm_bridge *bridge, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state) +{ + if (bridge->funcs->atomic_check) { + struct drm_bridge_state *bridge_state; + int ret; + + bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state, + bridge); + if (WARN_ON(!bridge_state)) + return -EINVAL; + + ret = bridge->funcs->atomic_check(bridge, bridge_state, + crtc_state, conn_state); + if (ret) + return ret; + } else if (bridge->funcs->mode_fixup) { + if (!bridge->funcs->mode_fixup(bridge, &crtc_state->mode, + &crtc_state->adjusted_mode)) + return -EINVAL; + } + + return 0; +} + +/** + * drm_atomic_bridge_chain_check() - Do an atomic check on the bridge chain + * @bridge: bridge control structure + * @crtc_state: new CRTC state + * @conn_state: new connector state + * + * Calls &drm_bridge_funcs.atomic_check() (falls back on + * &drm_bridge_funcs.mode_fixup()) op for all the bridges in the encoder chain, + * starting from the last bridge to the first. These are called before calling + * &drm_encoder_helper_funcs.atomic_check() + * + * RETURNS: + * 0 on success, a negative error code on failure + */ +int drm_atomic_bridge_chain_check(struct drm_bridge *bridge, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state) +{ + struct drm_encoder *encoder = bridge->encoder; + struct drm_bridge *iter; + + list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) { + int ret; + + ret = drm_atomic_bridge_check(iter, crtc_state, conn_state); + if (ret) + return ret; + + if (iter == bridge) + break; + } + + return 0; +} +EXPORT_SYMBOL(drm_atomic_bridge_chain_check); + /** * __drm_atomic_helper_bridge_reset() - Initialize a bridge state to its * default -- cgit v1.2.3