On Mon, Mar 13, 2023 at 09:06:50AM +0100, Neil Armstrong wrote: > On 11/03/2023 13:46, Jianhua Lu wrote: > > On Sat, Mar 11, 2023 at 01:38:52PM +0100, Konrad Dybcio wrote: > > > > > > > > > On 11.03.2023 13:32, Jianhua Lu wrote: > > > > Add a driver for panels using the Novatek NT36523 display driver IC. > > > > > > > > Signed-off-by: Jianhua Lu <lujianhua000@xxxxxxxxx> > > > > --- > > > [...] > > > > > > > + > > > > +static int nt36523_get_modes(struct drm_panel *panel, > > > > + struct drm_connector *connector) > > > > +{ > > > > + struct panel_info *pinfo = to_panel_info(panel); > > > > + int i; > > > > + > > > > + for (i = 0; i < pinfo->desc->num_modes; i++) { > > > > + const struct drm_display_mode *m = &pinfo->desc->modes[i]; > > > > + struct drm_display_mode *mode; > > > > + > > > > + mode = drm_mode_duplicate(connector->dev, m); > > > > + if (!mode) { > > > > + dev_err(panel->dev, "failed to add mode %ux%u@%u\n", > > > > + m->hdisplay, m->vdisplay, drm_mode_vrefresh(m)); > > > > + return -ENOMEM; > > > > + } > > > > + > > > > + mode->type = DRM_MODE_TYPE_DRIVER; > > > > + if (pinfo->desc->num_modes == 1) > > > > + mode->type |= DRM_MODE_TYPE_PREFERRED; > > > That's not quite correct, as that means "if you have more than one > > > defined panel mode (say 60Hz and 120 Hz), there will be no preferred one". > > This piece of code I see in the other panels, so I'm not sure if it is > > correct. Jianhua is correct that the same code exists in several places, and from a quick browse I consider all the cases bogus. It would be fine if someone volunteered to fix all the panels so we avoid this bug to creep into more panel drivers. Sam