From: Luca Ceresoli Date: Fri, 9 May 2025 13:53:47 +0000 (+0200) Subject: drm/bridge: panel: convert to devm_drm_bridge_alloc() API X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6ad88bf9e74dae83c992d8a16683360117b7e2d8;p=thirdparty%2Flinux.git drm/bridge: panel: convert to devm_drm_bridge_alloc() API This is the new API for allocating DRM bridges. The devm lifetime management of this driver is peculiar. The underlying device for the panel_bridge is the panel, and the devm lifetime is tied the panel device (panel->dev). However the panel_bridge allocation is not performed by the panel driver, but rather by a separate entity (typically the previous bridge in the encoder chain). Thus when that separate entity is destroyed, the panel_bridge is not removed automatically by devm, so it is rather done explicitly by calling drm_panel_bridge_remove(). This is the function that does devm_kfree() the panel_bridge in current code, so update it as well to put the bridge reference instead. This is a temporary solution until the panel lifetime is reworked, which should make this workaround unnecessary, so add a comment to clarify that. Acked-by: Maxime Ripard Link: https://lore.kernel.org/r/20250509-drm-bridge-convert-to-alloc-api-v3-21-b8bc1f16d7aa@bootlin.com Signed-off-by: Luca Ceresoli --- diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c index 79b009ab93960..6cbbfb1381a4a 100644 --- a/drivers/gpu/drm/bridge/panel.c +++ b/drivers/gpu/drm/bridge/panel.c @@ -287,15 +287,14 @@ struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel, if (!panel) return ERR_PTR(-EINVAL); - panel_bridge = devm_kzalloc(panel->dev, sizeof(*panel_bridge), - GFP_KERNEL); - if (!panel_bridge) - return ERR_PTR(-ENOMEM); + panel_bridge = devm_drm_bridge_alloc(panel->dev, struct panel_bridge, bridge, + &panel_bridge_bridge_funcs); + if (IS_ERR(panel_bridge)) + return (void *)panel_bridge; panel_bridge->connector_type = connector_type; panel_bridge->panel = panel; - panel_bridge->bridge.funcs = &panel_bridge_bridge_funcs; panel_bridge->bridge.of_node = panel->dev->of_node; panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES; panel_bridge->bridge.type = connector_type; @@ -327,7 +326,8 @@ void drm_panel_bridge_remove(struct drm_bridge *bridge) panel_bridge = drm_bridge_to_panel_bridge(bridge); drm_bridge_remove(bridge); - devm_kfree(panel_bridge->panel->dev, bridge); + /* TODO remove this after reworking panel_bridge lifetime */ + devm_drm_put_bridge(panel_bridge->panel->dev, bridge); } EXPORT_SYMBOL(drm_panel_bridge_remove);