It's the responsibility of a correctly written DRM modeset driver to call drm_atomic_helper_shutdown() at shutdown time and that should be disabling / unpreparing the panel if needed. Panel drivers shouldn't be calling these functions themselves.
A recent effort was made to fix as many DRM modeset drivers as possible [1] [2] [3] and most drivers are fixed now. Unfortunately, it's very difficult to know exactly which DRM modeset drivers are using panel-simple due to the sheer number of panels it handles. For now, we'll leave the calls and just add a comment to keep people from copying this code. [1] https://lore.kernel.org/r/20230901234015.566018-1-diand...@chromium.org [2] https://lore.kernel.org/r/20230901234202.566951-1-diand...@chromium.org [3] https://lore.kernel.org/r/20230921192749.1542462-1-diand...@chromium.org Signed-off-by: Douglas Anderson <diand...@chromium.org> --- Changes in v2: - Only handle 1 panel per patch. - Split removal of prepared/enabled from handling of remove/shutdown. - panel-edp and panel-simple just get a comment now. drivers/gpu/drm/panel/panel-simple.c | 33 +++++++++++++++++++--------- 1 file changed, 23 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index 42d902d2bbbe..f39122ffdead 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -716,26 +716,39 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc) return err; } -static void panel_simple_remove(struct device *dev) +static void panel_simple_shutdown(struct device *dev) { struct panel_simple *panel = dev_get_drvdata(dev); - drm_panel_remove(&panel->base); + /* + * NOTE: the following two calls don't really belong here. It is the + * responsibility of a correctly written DRM modeset driver to call + * drm_atomic_helper_shutdown() at shutdown time and that should + * cause the panel to be disabled / unprepared if needed. For now, + * however, we'll keep these calls due to the sheer number of + * different DRM modeset drivers used with panel-simple. The fact that + * we're calling these and _also_ the drm_atomic_helper_shutdown() + * will try to disable/unprepare means that we can get a warning about + * trying to disable/unprepare an already disabled/unprepared panel, + * but that's something we'll have to live with until we've confirmed + * that all DRM modeset drivers are properly calling + * drm_atomic_helper_shutdown(). + */ drm_panel_disable(&panel->base); drm_panel_unprepare(&panel->base); - - pm_runtime_dont_use_autosuspend(dev); - pm_runtime_disable(dev); - if (panel->ddc) - put_device(&panel->ddc->dev); } -static void panel_simple_shutdown(struct device *dev) +static void panel_simple_remove(struct device *dev) { struct panel_simple *panel = dev_get_drvdata(dev); - drm_panel_disable(&panel->base); - drm_panel_unprepare(&panel->base); + drm_panel_remove(&panel->base); + panel_simple_shutdown(dev); + + pm_runtime_dont_use_autosuspend(dev); + pm_runtime_disable(dev); + if (panel->ddc) + put_device(&panel->ddc->dev); } static const struct drm_display_mode ampire_am_1280800n3tzqw_t00h_mode = { -- 2.45.0.rc1.225.g2a3ae87e7f-goog
