From 5061b8a969f7cd40f8d81f76e22a5e4fb13d6665 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Tue, 28 Jan 2020 14:55:07 +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). v10: * Add changelog to the commit message v8 -> v9: * No changes v7: * Fix a NULL pointer dereference v5 -> v6: * No changes v4: * Add R-bs v3: * No changes v2: * Clarify the fact that ->atomic_check() is replacing ->mode_fixup() 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/20200128135514.108171-6-boris.brezillon@collabora.com --- drivers/gpu/drm/drm_atomic_helper.c | 12 +++---- drivers/gpu/drm/drm_bridge.c | 66 +++++++++++++++++++++++++++++++++++++ 2 files changed, 72 insertions(+), 6 deletions(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index df76fe985cd2..003c687e3b73 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -437,12 +437,12 @@ mode_fixup(struct drm_atomic_state *state) funcs = encoder->helper_private; bridge = drm_bridge_chain_get_first_bridge(encoder); - ret = drm_bridge_chain_mode_fixup(bridge, - &new_crtc_state->mode, - &new_crtc_state->adjusted_mode); - if (!ret) { - DRM_DEBUG_ATOMIC("Bridge fixup failed\n"); - return -EINVAL; + ret = drm_atomic_bridge_chain_check(bridge, + new_crtc_state, + new_conn_state); + if (ret) { + DRM_DEBUG_ATOMIC("Bridge atomic check failed\n"); + return ret; } if (funcs && funcs->atomic_check) { diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index f6206e655da4..c8beb1385771 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -602,6 +602,72 @@ 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; + struct drm_bridge *iter; + + if (!bridge) + return 0; + + encoder = bridge->encoder; + 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); + #ifdef CONFIG_OF /** * of_drm_find_bridge - find the bridge corresponding to the device node in -- cgit