kernel/linux.git/drivers/gpu/drm/bridge/panel.c, branch v6.3

drm/bridge: panel: Prevent ERR_PTR Dereference

2023-01-05T07:50:05+00:00

Commit 5ea6b1702781 ("drm/panel: Add prepare_prev_first flag to drm_panel") introduced an access to the bridge pointer in the devm_drm_panel_bridge_add_typed() function. However, due to the unusual ERR_PTR check when getting that pointer, the pointer access is done even though the pointer might be an error pointer. Rework the function for a more traditional design that will return immediately if it gets an ERR_PTR so that we never access the pointer in that case. Fixes: 5ea6b1702781 ("drm/panel: Add prepare_prev_first flag to drm_panel") Reported-by: kernel test robot Reported-by: Dan Carpenter Reviewed-by: Laurent Pinchart Reviewed-by: Andrzej Hajda Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20230102120123.19062-1-maxime@cerno.tech Link: https://patchwork.freedesktop.org/patch/msgid/20230102120123.19062-1-maxime@cerno.tech

drm/bridge: panel: Set pre_enable_prev_first from drmm_panel_bridge_add

2023-01-02T10:38:43+00:00

Commit 5ea6b1702781 ("drm/panel: Add prepare_prev_first flag to drm_panel") added code to copy prepare_prev_first from drm_panel to pre_enable_prev_first in drm_bridge when called through devm_panel_bridge_add, but missed drmm_panel_bridge_add. Add the same code to drmm_panel_bridge_add. Fixes: 5ea6b1702781 ("drm/panel: Add prepare_prev_first flag to drm_panel") Signed-off-by: Dave Stevenson Reviewed-by: Jagan Teki Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20221222185213.3773336-1-dave.stevenson@raspberrypi.com

drm/panel: Add prepare_prev_first flag to drm_panel

2022-12-08T08:56:57+00:00

Mapping to the drm_bridge flag pre_enable_prev_first, add a new flag prepare_prev_first to drm_panel to allow the panel driver to request that the upstream bridge should be pre_enabled before the panel prepare. Signed-off-by: Dave Stevenson Reviewed-by: Dmitry Baryshkov Link: https://lore.kernel.org/r/20221205173328.1395350-6-dave.stevenson@raspberrypi.com Signed-off-by: Maxime Ripard

drm/bridge: panel: Introduce drmm_of_get_bridge

2022-07-13T08:46:06+00:00

Unlike what can be found for other DRM entities, we don't have a DRM-managed function equivalent to devm_drm_of_get_bridge(). Let's create it. Acked-by: Sam Ravnborg Acked-by: Thomas Zimmermann Signed-off-by: Maxime Ripard Link: https://lore.kernel.org/r/20220711173939.1132294-12-maxime@cerno.tech

drm/bridge: panel: Introduce drmm_panel_bridge_add

2022-07-13T08:46:06+00:00

Unlike what can be found for other entities, there's no DRM-managed function to create a panel_bridge instance from a panel. Let's introduce one. Acked-by: Sam Ravnborg Acked-by: Thomas Zimmermann Signed-off-by: Maxime Ripard Link: https://lore.kernel.org/r/20220711173939.1132294-11-maxime@cerno.tech

drm: Config orientation property if panel provides it

2022-06-21T15:52:59+00:00

Panel orientation property should be set before drm_dev_register(). Some drm driver calls drm_dev_register() in .bind(). However, most panels sets orientation property relatively late, mostly in .get_modes() callback, since this is when they are able to get the connector and binds the orientation property to it, though the value should be known when the panel is probed. In drm_bridge_connector_init(), if a bridge is a panel bridge, use it to set the connector's panel orientation property. Suggested-by: Douglas Anderson Signed-off-by: Hsin-Yi Wang Reviewed-by: Douglas Anderson Reviewed-by: Stephen Boyd [dianders: fixed space vs. tab indentation] Signed-off-by: Douglas Anderson Link: https://patchwork.freedesktop.org/patch/msgid/20220609072722.3488207-9-hsinyi@chromium.org

drm: bridge: panel: Register connector if DRM device is already registered

2022-04-19T16:11:27+00:00

If panel_bridge_attach() happens after DRM device registration, the created connector will not be registered by the DRM core anymore. Fix this by registering it explicitly in such case. This fixes the following issue observed on Samsung Exynos4210-based Trats board with a DSI panel (the panel driver is registered after the Exynos DRM component device is bound): $ ./modetest -c -Mexynos could not get connector 56: No such file or directory Segmentation fault While touching this, move the connector reset() call also under the DRM device registered check, because otherwise it is not really needed. Fixes: 934aef885f9d ("drm: bridge: panel: Reset the connector state pointer") Signed-off-by: Marek Szyprowski Reviewed-by: Jagan Teki Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20220419091422.4255-1-m.szyprowski@samsung.com

drm: bridge: panel: Reset the connector state pointer

2022-03-31T14:21:31+00:00

Trigger hotplug event with drm_kms_helper_hotplug_event might fail if the connector state pointer is NULL. BUG observed in exynos dsi driver where drm_bridge_attach is trying to register a connector in panel_bridge before the hotplug event is triggered. WARNING: CPU: 1 PID: 1 at drivers/gpu/drm/drm_atomic_state_helper.c:494 drm_atomic_helper_connector_duplicate_state+0x94/0x9c Modules linked in: CPU: 1 PID: 1 Comm: swapper/0 Tainted: G W 5.16.0-rc1-00009-g704b1dbfa4c2 #11058 Hardware name: Samsung Exynos (Flattened Device Tree) [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [] (show_stack) from [] (dump_stack_lvl+0x58/0x70) [] (dump_stack_lvl) from [] (__warn+0xd0/0x134) [] (__warn) from [] (warn_slowpath_fmt+0x5c/0xb4) [] (warn_slowpath_fmt) from [] (drm_atomic_helper_connector_duplicate_state+0x94/0x9c) [] (drm_atomic_helper_connector_duplicate_state) from [] (drm_atomic_get_connector_state+0xd4/0x190) [] (drm_atomic_get_connector_state) from [] (__drm_atomic_helper_set_config+0x314/0x368) [] (__drm_atomic_helper_set_config) from [] (drm_client_modeset_commit_atomic+0x170/0x278) [] (drm_client_modeset_commit_atomic) from [] (drm_client_modeset_commit_locked+0x60/0x1c8) [] (drm_client_modeset_commit_locked) from [] (drm_client_modeset_commit+0x24/0x40) [] (drm_client_modeset_commit) from [] (drm_fb_helper_set_par+0xb8/0xf8) [] (drm_fb_helper_set_par) from [] (fbcon_init+0x2c0/0x518) [] (fbcon_init) from [] (visual_init+0xc0/0x108) [] (visual_init) from [] (do_bind_con_driver+0x1b8/0x3a4) [] (do_bind_con_driver) from [] (do_take_over_console+0x13c/0x1e8) [] (do_take_over_console) from [] (do_fbcon_takeover+0x78/0xd8) [] (do_fbcon_takeover) from [] (register_framebuffer+0x208/0x2e0) [] (register_framebuffer) from [] (__drm_fb_helper_initial_config_and_unlock+0x400/0x63c) [] (__drm_fb_helper_initial_config_and_unlock) from [] (drm_kms_helper_hotplug_event+0x24/0x30) [] (drm_kms_helper_hotplug_event) from [] (exynos_dsi_host_attach+0x174/0x1fc) [] (exynos_dsi_host_attach) from [] (s6e8aa0_probe+0x1b4/0x218) So reset the atomic state for a given connector by freeing the state pointer and allocate a new empty state object. This can be done using connector funcs->reset helper and has to be done before the hotplug even calls. This patch calls the connector->funcs->reset in panel_bridge_attach. Signed-off-by: Jagan Teki Acked-by: Marek Szyprowski Tested-by: Marek Szyprowski Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20220303163654.3381470-3-jagan@amarulasolutions.com

drm: Plumb debugfs_init through to panels

2022-02-15T23:25:18+00:00

We'd like panels to be able to add things to debugfs underneath the connector's directory. Let's plumb it through. A panel will be able to put things in a "panel" directory under the connector's directory. Note that debugfs is not ABI and so it's always possible that the location that the panel gets for its debugfs could change in the future. NOTE: this currently only works if you're using a modern architecture. Specifically the plumbing relies on _both_ drm_bridge_connector and drm_panel_bridge. If you're not using one or both of these things then things won't be plumbed through. As a side effect of this change, drm_bridges can also get callbacks to put stuff underneath the connector's debugfs directory. At the moment all bridges in the chain have their debugfs_init() called with the connector's root directory. Signed-off-by: Douglas Anderson Reviewed-by: Javier Martinez Canillas Reviewed-by: Laurent Pinchart Link: https://patchwork.freedesktop.org/patch/msgid/20220204161245.v2.2.Ib0bd5346135cbb0b63006b69b61d4c8af6484740@changeid

drm/bridge: Move devm_drm_of_get_bridge to bridge/panel.c

2021-09-22T08:44:00+00:00

By depending on devm_drm_panel_bridge_add(), devm_drm_of_get_bridge() introduces a circular dependency between the modules drm (where devm_drm_of_get_bridge() ends up) and drm_kms_helper (where devm_drm_panel_bridge_add() is). Fix this by moving devm_drm_of_get_bridge() to bridge/panel.c and thus drm_kms_helper. Fixes: 87ea95808d53 ("drm/bridge: Add a function to abstract away panels") Reported-by: Stephen Rothwell Signed-off-by: Maxime Ripard Tested-by: Heiko Stuebner Acked-by: Thomas Zimmermann Link: https://patchwork.freedesktop.org/patch/msgid/20210917180925.2602266-1-maxime@cerno.tech