From patchwork Thu Jan 24 03:27:10 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [58/74] drm/nouveau: fix blank LVDS screen regression on pre-nv50 cards Date: Wed, 23 Jan 2013 17:27:10 -0000 From: Herton Ronaldo Krzesinski X-Patchwork-Id: 215168 Message-Id: <1358998046-613-59-git-send-email-herton.krzesinski@canonical.com> To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Marcin Slusarz , Ben Skeggs 3.5.7.4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Marcin Slusarz commit 92441b2263866c27ef48137be5aa6c8c692652fc upstream. Commit 2a44e499 ("drm/nouveau/disp: introduce proper init/fini, separate from create/destroy") started to call display init routines on pre-nv50 hardware on module load. But LVDS init code sets driver state in a way which prevents modesetting code from operating properly. nv04_display_init calls nv04_dfp_restore, which sets encoder->last_dpms to NV_DPMS_CLEARED. drm_crtc_helper_set_mode nv04_dfp_prepare nv04_lvds_dpms(DRM_MODE_DPMS_OFF) nv04_lvds_dpms checks last_dpms mode (which is NV_DPMS_CLEARED) and wrongly assumes it's a "powersaving mode", the new one (DRM_MODE_DPMS_OFF) is too, so it skips calling some crucial lvds scripts. Reported-by: Chris Paulson-Ellis Signed-off-by: Marcin Slusarz Signed-off-by: Ben Skeggs Signed-off-by: Herton Ronaldo Krzesinski --- drivers/gpu/drm/nouveau/nv04_dfp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/nouveau/nv04_dfp.c b/drivers/gpu/drm/nouveau/nv04_dfp.c index 11c9a1a..28c7a5a 100644 --- a/drivers/gpu/drm/nouveau/nv04_dfp.c +++ b/drivers/gpu/drm/nouveau/nv04_dfp.c @@ -504,7 +504,7 @@ static void nv04_dfp_update_backlight(struct drm_encoder *encoder, int mode) static inline bool is_powersaving_dpms(int mode) { - return (mode != DRM_MODE_DPMS_ON); + return mode != DRM_MODE_DPMS_ON && mode != NV_DPMS_CLEARED; } static void nv04_lvds_dpms(struct drm_encoder *encoder, int mode)