Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751506AbdHDI7A (ORCPT ); Fri, 4 Aug 2017 04:59:00 -0400 Received: from mail-wm0-f68.google.com ([74.125.82.68]:33403 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751284AbdHDI65 (ORCPT ); Fri, 4 Aug 2017 04:58:57 -0400 Date: Fri, 4 Aug 2017 10:58:53 +0200 From: Daniel Vetter To: David Lechner Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Daniel Vetter Subject: Re: [PATCH v3 2/2] drm/fb-helper: pass physical dimensions to fbdev Message-ID: <20170804085853.wwdzv54z4dqslpem@phenom.ffwll.local> Mail-Followup-To: David Lechner , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Daniel Vetter References: <1501777149-8310-1-git-send-email-david@lechnology.com> <1501777149-8310-3-git-send-email-david@lechnology.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1501777149-8310-3-git-send-email-david@lechnology.com> X-Operating-System: Linux phenom 4.11.0-2-amd64 User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2628 Lines: 76 On Thu, Aug 03, 2017 at 11:19:09AM -0500, David Lechner wrote: > The fbdev subsystem has a place for physical dimensions (width and height > in mm) that is readable by userspace. Since DRM also knows these > dimensions, pass this information to the fbdev device. > > This has to be done in drm_setup_crtcs_fb() instead of drm_setup_crtcs() > because fb_helper->fbdev may be NULL in drm_setup_crtcs(). > > Signed-off-by: David Lechner > --- > drivers/gpu/drm/drm_fb_helper.c | 15 +++++++++++++-- > 1 file changed, 13 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c > index 24a721a..a98bf86 100644 > --- a/drivers/gpu/drm/drm_fb_helper.c > +++ b/drivers/gpu/drm/drm_fb_helper.c > @@ -1882,8 +1882,6 @@ void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helpe > info->var.xoffset = 0; > info->var.yoffset = 0; > info->var.activate = FB_ACTIVATE_NOW; > - info->var.height = -1; > - info->var.width = -1; > > switch (fb->format->depth) { > case 8: > @@ -2435,11 +2433,24 @@ static void drm_setup_crtcs(struct drm_fb_helper *fb_helper, > */ > static void drm_setup_crtcs_fb(struct drm_fb_helper *fb_helper) > { > + struct fb_info *info = fb_helper->fbdev; > int i; > > for (i = 0; i < fb_helper->crtc_count; i++) > if (fb_helper->crtc_info[i].mode_set.num_connectors) > fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb; > + > + drm_fb_helper_for_each_connector(fb_helper, i) { > + struct drm_connector *connector = > + fb_helper->connector_info[i]->connector; > + > + /* use first connected connector for the physical dimensions */ > + if (connector->status == connector_status_connected) { > + info->var.height = connector->display_info.width_mm; > + info->var.width = connector->display_info.height_mm; > + break; > + } > + } Ok, small trapdoor I didn't highlight: Accessing the connector prope state (i.e. ->status and ->display_info) requires that you hold dev->mode_config.mutex. See how it's done in drm_setup_crtcs, just wrap it around this loop here. fbdev state itself is protected by fb_helper->lock, so that part is all good. I've applied patch 1 already, but can you pls respin that one with the locking fixed up? Thanks, Daniel > } > > /* Note: Drops fb_helper->lock before returning. */ > -- > 2.7.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch