Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [Medium] drm/bridge: ssd2825: duplicate atomic_enable() call on next_bridge --
commit 1c5e404afec7538a0e06a870cc1167b8db336814 Author: Svyatoslav Ryhel <[email protected]> drm/bridge: ssd2825: Fix panel enable sequence This commit invokes the next bridge's atomic_enable() callback directly at the end of ssd2825_bridge_atomic_pre_enable() to restore panel output after commit 554d36acf5e0 removed direct panel handling. > diff --git a/drivers/gpu/drm/bridge/ssd2825.c > b/drivers/gpu/drm/bridge/ssd2825.c > index 71877699dfab6..9216cee09115f 100644 > --- a/drivers/gpu/drm/bridge/ssd2825.c > +++ b/drivers/gpu/drm/bridge/ssd2825.c > @@ -475,6 +475,7 @@ static void ssd2825_bridge_atomic_pre_enable(struct > drm_bridge *bridge, > struct drm_atomic_commit *state) > { > struct ssd2825_priv *priv = bridge_to_ssd2825(bridge); > + struct drm_bridge *next_bridge = priv->output.bridge; > struct mipi_dsi_device *dsi_dev = priv->output.dev; > const struct drm_crtc_state *crtc_state; > const struct drm_display_mode *mode; > @@ -569,6 +570,14 @@ static void ssd2825_bridge_atomic_pre_enable(struct > drm_bridge *bridge, > /* Initial DSI configuration register set */ > ssd2825_write_reg(priv, SSD2825_CONFIGURATION_REG, config); > ssd2825_write_reg(priv, SSD2825_VC_CTRL_REG, 0); > + > + /* > + * The SSD2825 requires that the next bridge be enabled first; > + * otherwise, the SSD2825 cannot complete its configuration and > + * there will be no output. > + */ > + if (next_bridge->funcs && next_bridge->funcs->atomic_enable) > + next_bridge->funcs->atomic_enable(next_bridge, state); [Severity: Medium] Does calling next_bridge->funcs->atomic_enable() directly in ssd2825_bridge_atomic_pre_enable() cause next_bridge->funcs->atomic_enable() to be invoked twice on every modeset enable? In drivers/gpu/drm/bridge/ssd2825.c, ssd2825_bridge_attach() attaches priv->output.bridge to the encoder's bridge chain: return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge, flags); During an atomic modeset enable, drm_atomic_helper_commit_modeset_enables() runs drm_atomic_bridge_chain_pre_enable(), which calls ssd2825_bridge_atomic_pre_enable() and now invokes next_bridge->funcs->atomic_enable() for the first time. Immediately afterwards, drm_atomic_helper_commit_encoder_bridge_enable() calls drm_atomic_bridge_chain_enable() in drivers/gpu/drm/drm_bridge.c: drm_for_each_bridge_in_chain_from(first_bridge, bridge) if (bridge->funcs->atomic_enable) bridge->funcs->atomic_enable(bridge, state); This calls next_bridge->funcs->atomic_enable() a second time while drm_atomic_bridge_chain_disable() only calls atomic_disable() once. When next_bridge is a panel bridge, panel_bridge_atomic_enable() calls drm_panel_enable() in drivers/gpu/drm/drm_panel.c, where the second call hits the already-enabled check and emits a warning on every modeset: if (panel->enabled) { dev_warn(panel->dev, "Skipping enable of already enabled panel\n"); return; } When next_bridge is a non-panel drm_bridge, there is no enabled-state guard in the DRM bridge core, so next_bridge->funcs->atomic_enable() runs twice without a matching second disable. Additionally, if next_bridge sets pre_enable_prev_first, drm_atomic_bridge_chain_pre_enable() runs ssd2825_bridge_atomic_pre_enable() before next_bridge->funcs->atomic_pre_enable(), which would cause next_bridge->funcs->atomic_enable() to run before next_bridge has been prepared in atomic_pre_enable(). -- Sashiko AI review ยท https://sashiko.dev/#/patchset/[email protected]?part=1
