From aa4cd9100e0709ea0bc6f85090188ace895e51fe Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Wed, 22 Jan 2014 16:42:02 +0100 Subject: [PATCH] drm/doc: Document drm_helper_resume_force_mode Stumbled over while reviewing all occurences in the DRM doc talking about suspend/resume. Reviewed-by: Alex Deucher Signed-off-by: Daniel Vetter --- Documentation/DocBook/drm.tmpl | 7 +++++-- drivers/gpu/drm/drm_crtc_helper.c | 9 +++++++++ 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl index 26539ee3c63e..8e1052434bab 100644 --- a/Documentation/DocBook/drm.tmpl +++ b/Documentation/DocBook/drm.tmpl @@ -1151,8 +1151,11 @@ int max_width, max_height; This operation is called with the mode config lock held. - FIXME: How should set_config interact with DPMS? If the CRTC is - suspended, should it be resumed? + Note that the drm core has no notion of restoring the mode setting + state after resume, since all resume handling is in the full + responsibility of the driver. The common mode setting helper library + though provides a helper which can be used for this: + drm_helper_resume_force_mode. diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c index ea92b827e787..85d476abea6c 100644 --- a/drivers/gpu/drm/drm_crtc_helper.c +++ b/drivers/gpu/drm/drm_crtc_helper.c @@ -943,6 +943,15 @@ int drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb, } EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct); +/** + * drm_helper_resume_force_mode - force-restore mode setting configuration + * @dev: drm_device which should be restored + * + * Drivers which use the mode setting helpers can use this function to + * force-restore the mode setting configuration e.g. on resume or when something + * else might have trampled over the hw state (like some overzealous old BIOSen + * tended to do). + */ int drm_helper_resume_force_mode(struct drm_device *dev) { struct drm_crtc *crtc; -- 2.39.2