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 | 42 +++++++++++++++++++++++++++++++++++++ include/drm/drm_panel.h | 7 +++++++ 2 files changed, 49 insertions(+) diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index dbd5b873e8f2..507099af4b57 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -172,6 +172,48 @@ 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, + enum drm_panel_orientation *orientation) +{ + int rotation, ret; + + ret = of_property_read_u32(np, "rotation", &rotation); + if (ret == -EINVAL) { + /* Don't return an error if there's no rotation property. */ + *orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN; + return 0; + } + + if (ret < 0) + return ret; + + if (rotation == 0) + *orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL; + else if (rotation == 90) + *orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP; + else if (rotation == 180) + *orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP; + else if (rotation == 270) + *orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP; + else + return -EINVAL; + + return 0; +} +EXPORT_SYMBOL(of_drm_get_panel_orientation); #endif MODULE_AUTHOR("Thierry Reding <treding@xxxxxxxxxx>"); diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h index 8c738c0e6e9f..3564952f1a4f 100644 --- a/include/drm/drm_panel.h +++ b/include/drm/drm_panel.h @@ -197,11 +197,18 @@ int drm_panel_detach(struct drm_panel *panel); #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL) struct drm_panel *of_drm_find_panel(const struct device_node *np); +int of_drm_get_panel_orientation(const struct device_node *np, + enum drm_panel_orientation *orientation); #else static inline struct drm_panel *of_drm_find_panel(const struct device_node *np) { return ERR_PTR(-ENODEV); } +int of_drm_get_panel_orientation(const struct device_node *np, + enum drm_panel_orientation *orientation) +{ + return -ENODEV; +} #endif #endif -- 2.22.0.410.gd8fdbe21b5-goog _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel