Hi Derek. On Mon, Jun 10, 2019 at 09:03:46PM -0700, Derek Basehore wrote: > This adds a helper function for reading the rotation (panel > orientation) from the device tree. > > Signed-off-by: Derek Basehore <dbasehore@xxxxxxxxxxxx> > --- > drivers/gpu/drm/drm_panel.c | 41 +++++++++++++++++++++++++++++++++++++ > include/drm/drm_panel.h | 7 +++++++ > 2 files changed, 48 insertions(+) > > diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c > index dbd5b873e8f2..3b689ce4a51a 100644 > --- a/drivers/gpu/drm/drm_panel.c > +++ b/drivers/gpu/drm/drm_panel.c > @@ -172,6 +172,47 @@ struct drm_panel *of_drm_find_panel(const struct device_node *np) > return ERR_PTR(-EPROBE_DEFER); > } > EXPORT_SYMBOL(of_drm_find_panel); > + > +/** > + * of_drm_get_panel_orientation - look up the rotation of the panel using a > + * device tree node > + * @np: device tree node of the panel > + * @orientation: orientation enum to be filled in > + * > + * Looks up the rotation of a panel in the device tree. The rotation in the > + * device tree is counter clockwise. > + * > + * Return: 0 when a valid rotation value (0, 90, 180, or 270) is read or the > + * rotation property doesn't exist. -EERROR otherwise. > + */ > +int of_drm_get_panel_orientation(const struct device_node *np, int *orientation) > +{ > + int rotation, ret; > + > + ret = of_property_read_u32(np, "rotation", &rotation); I just noticed that everywhere this code talks about orientation, but the property that it reads are rotation. To my best understanding these are not the same. Sam