Since commit b5dc0d10 (drm/imx: kill firstopen callback) the following probe failure is seen: [drm] Supports vblank timestamp caching Rev 1 (10.10.2010). [drm] No driver support for vblank timestamp query. [drm] Initialized imx-drm 1.0.0 20120507 on minor 0 imx-ldb ldb.10: adding encoder failed with -16 imx-ldb: probe of ldb.10 failed with error -16 imx-ipuv3 2400000.ipu: IPUv3H probed imx-ipuv3 2800000.ipu: IPUv3H probed imx-ipuv3-crtc imx-ipuv3-crtc.0: adding crtc failed with -16. imx-ipuv3-crtc: probe of imx-ipuv3-crtc.0 failed with error -16 imx-ipuv3-crtc imx-ipuv3-crtc.1: adding crtc failed with -16. imx-ipuv3-crtc: probe of imx-ipuv3-crtc.1 failed with error -16 imx-ipuv3-crtc imx-ipuv3-crtc.2: adding crtc failed with -16. imx-ipuv3-crtc: probe of imx-ipuv3-crtc.2 failed with error -16 imx-ipuv3-crtc imx-ipuv3-crtc.3: adding crtc failed with -16. imx-ipuv3-crtc: probe of imx-ipuv3-crtc.3 failed with error -16 The reason for the probe failure is that now 'imxdrm->references' is incremented early in imx_drm_driver_load(), so the following checks in imx_drm_add_crtc() and imx_drm_add_encoder(): if (imxdrm->references) { ret = -EBUSY; goto err_busy; } ,will always fail. Instead of manually keeping the references in the imx-drm driver, let's use drm->open_count. After this patch, lvds panel is functional on a mx6qsabrelite board. Signed-off-by: Fabio Estevam <fabio.estevam@xxxxxxxxxxxxx> Acked-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> --- Greg, The offending commit that causes the regression is in 3.12-rc1 now, so this patch could go via your staging tree. Changes since v3: - Add Acked-by from Sascha Changes since v2: - Use imxdrm->drm->open_count for checking the references Changes since v1: - Improved commit log by providing an explanation to the probe failure - Cc'ed Dave/Daniel drivers/staging/imx-drm/imx-drm-core.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/staging/imx-drm/imx-drm-core.c b/drivers/staging/imx-drm/imx-drm-core.c index 47c5888..a2e52a0 100644 --- a/drivers/staging/imx-drm/imx-drm-core.c +++ b/drivers/staging/imx-drm/imx-drm-core.c @@ -41,7 +41,6 @@ struct imx_drm_device { struct list_head encoder_list; struct list_head connector_list; struct mutex mutex; - int references; int pipes; struct drm_fbdev_cma *fbhelper; }; @@ -241,8 +240,6 @@ struct drm_device *imx_drm_device_get(void) } } - imxdrm->references++; - return imxdrm->drm; unwind_crtc: @@ -280,8 +277,6 @@ void imx_drm_device_put(void) list_for_each_entry(enc, &imxdrm->encoder_list, list) module_put(enc->owner); - imxdrm->references--; - mutex_unlock(&imxdrm->mutex); } EXPORT_SYMBOL_GPL(imx_drm_device_put); @@ -485,7 +480,7 @@ int imx_drm_add_crtc(struct drm_crtc *crtc, mutex_lock(&imxdrm->mutex); - if (imxdrm->references) { + if (imxdrm->drm->open_count) { ret = -EBUSY; goto err_busy; } @@ -564,7 +559,7 @@ int imx_drm_add_encoder(struct drm_encoder *encoder, mutex_lock(&imxdrm->mutex); - if (imxdrm->references) { + if (imxdrm->drm->open_count) { ret = -EBUSY; goto err_busy; } @@ -709,7 +704,7 @@ int imx_drm_add_connector(struct drm_connector *connector, mutex_lock(&imxdrm->mutex); - if (imxdrm->references) { + if (imxdrm->drm->open_count) { ret = -EBUSY; goto err_busy; } -- 1.8.1.2 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel