On Tue, May 9, 2017 at 9:28 AM, Leonard Crestez <leonard.crestez@xxxxxxx> wrote: > On Wed, Mar 22, 2017 at 5:01 PM, Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> wrote: >> On Wed, 2017-03-22 at 08:26 -0500, Rob Herring wrote: >> > >> > Similar to the previous commit, convert drivers open coding OF graph >> > parsing to use drm_of_find_panel_or_bridge instead. >> > >> > This changes some error messages to debug messages (in the graph core). >> > Graph connections are often "no connects" depending on the particular >> > board, so we want to avoid spurious messages. Plus the kernel is not a >> > DT validator. >> > >> > Signed-off-by: Rob Herring <robh@xxxxxxxxxx> >> > Reviewed-by: Archit Taneja <architt@xxxxxxxxxxxxxx> >> Tested-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> >> (imx-ldb on i.MX6) > > It seems that this breaks on (at least) imx6qdl-sabreauto. The relevant > section of the boot log looks like this: > > imx-drm display-subsystem: bound imx-ipuv3-crtc.2 (ops ipu_crtc_ops) > imx-drm display-subsystem: bound imx-ipuv3-crtc.3 (ops ipu_crtc_ops) > dwhdmi-imx 120000.hdmi: Detected HDMI TX controller v1.31a with HDCP > (DWC HDMI 3D TX PHY) > dwhdmi-imx 120000.hdmi: registered DesignWare HDMI I2C bus driver > imx-drm display-subsystem: bound 120000.hdmi (ops dw_hdmi_imx_ops) > imx-drm display-subsystem: failed to bind 2000000.aips-bus:ldb (ops > imx_ldb_ops): -19 > imx-drm display-subsystem: master bind failed: -19 > > It seems that imx6qdl-sabreauto does not have any panel defined in dts. > This used to be ignored when of_graph_get_endpoint_by_regs returned > NULL but now drm_of_find_panel_or_bridge returns -ENODEV and this > causes imx_ldb_bind to fail altogether. Defining a panel works > (including showing stuff on a LVDS panel). Ignoring -ENODEV also fixes > this: > > --- drivers/gpu/drm/imx/imx-ldb.c > +++ drivers/gpu/drm/imx/imx-ldb.c > @@ -673,7 +673,7 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data) > ret = drm_of_find_panel_or_bridge(child, > imx_ldb->lvds_mux ? 4 : 2, 0, > &channel->panel, &channel->bridge); > - if (ret) > + if (ret != -ENODEV) > return ret; > > /* panel ddc only if there is no bridge */ > > I don't know much about drm and it's not clear if failing to find a > panel should be an error here or not and the hack above is likely the > wrong way to handle it anyway. That looks like the right fix to me. Ideally, the DT should probably define an LVDS connector node (if not a panel) in this case like we do for other cases with DDC, but more importantly we shouldn't require a DT update to fix things. If you needed power or gpio controls of the panel you would also need some node in DT. Do you mind sending a proper patch? Rob _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
