diff options
| author | Liu Ying <victor.liu@nxp.com> | 2023-11-23 11:26:15 +0800 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2023-11-25 00:47:46 +0100 |
| commit | 39d5b6a64ace77d0c11c398d272218df5f939abb (patch) | |
| tree | ffd8d8942c1f9addd9990448b5a948e035b83945 /drivers/gpu/drm/bridge | |
| parent | ab93edb2f94c3c0d5965be3815782472adbe3f52 (diff) | |
drm/bridge: panel: Check device dependency before managing device link
Some panel devices already depend on DRM device, like the panel in
arch/arm/boot/dts/st/ste-ux500-samsung-skomer.dts, because DRM device is
the ancestor of those panel devices. device_link_add() would fail by
returning a NULL pointer for those panel devices because of the existing
dependency. So, check the dependency by calling device_is_dependent()
before adding or deleting device link between panel device and DRM device
so that the link is managed only for independent panel devices.
Fixes: 887878014534 ("drm/bridge: panel: Fix device link for DRM_BRIDGE_ATTACH_NO_CONNECTOR")
Fixes: 199cf07ebd2b ("drm/bridge: panel: Add a device link between drm device and panel device")
Reported-by: Linus Walleij <linus.walleij@linaro.org>
Closes: https://lore.kernel.org/lkml/CACRpkdaGzXD6HbiX7mVUNJAJtMEPG00Pp6+nJ1P0JrfJ-ArMvQ@mail.gmail.com/T/
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231123032615.3760488-1-victor.liu@nxp.com
Diffstat (limited to 'drivers/gpu/drm/bridge')
| -rw-r--r-- | drivers/gpu/drm/bridge/panel.c | 27 |
1 files changed, 18 insertions, 9 deletions
diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c index e48823a4f1ed..5e8980023407 100644 --- a/drivers/gpu/drm/bridge/panel.c +++ b/drivers/gpu/drm/bridge/panel.c @@ -23,6 +23,7 @@ struct panel_bridge { struct drm_panel *panel; struct device_link *link; u32 connector_type; + bool is_independent; }; static inline struct panel_bridge * @@ -67,12 +68,17 @@ static int panel_bridge_attach(struct drm_bridge *bridge, struct drm_device *drm_dev = bridge->dev; int ret; - panel_bridge->link = device_link_add(drm_dev->dev, panel->dev, - DL_FLAG_STATELESS); - if (!panel_bridge->link) { - DRM_ERROR("Failed to add device link between %s and %s\n", - dev_name(drm_dev->dev), dev_name(panel->dev)); - return -EINVAL; + panel_bridge->is_independent = !device_is_dependent(drm_dev->dev, + panel->dev); + + if (panel_bridge->is_independent) { + panel_bridge->link = device_link_add(drm_dev->dev, panel->dev, + DL_FLAG_STATELESS); + if (!panel_bridge->link) { + DRM_ERROR("Failed to add device link between %s and %s\n", + dev_name(drm_dev->dev), dev_name(panel->dev)); + return -EINVAL; + } } if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) @@ -80,7 +86,8 @@ static int panel_bridge_attach(struct drm_bridge *bridge, if (!bridge->encoder) { DRM_ERROR("Missing encoder\n"); - device_link_del(panel_bridge->link); + if (panel_bridge->is_independent) + device_link_del(panel_bridge->link); return -ENODEV; } @@ -92,7 +99,8 @@ static int panel_bridge_attach(struct drm_bridge *bridge, panel_bridge->connector_type); if (ret) { DRM_ERROR("Failed to initialize connector\n"); - device_link_del(panel_bridge->link); + if (panel_bridge->is_independent) + device_link_del(panel_bridge->link); return ret; } @@ -115,7 +123,8 @@ static void panel_bridge_detach(struct drm_bridge *bridge) struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge); struct drm_connector *connector = &panel_bridge->connector; - device_link_del(panel_bridge->link); + if (panel_bridge->is_independent) + device_link_del(panel_bridge->link); /* * Cleanup the connector if we know it was initialized. |