[PATCH v4 1/8] drm/panel: Add an API drm_panel_get_orientation() to return panel orientation

From: Hsin-Yi Wang
Date: Mon Jun 06 2022 - 11:24:51 EST


Panels usually call drm_connector_set_panel_orientation(), which is
later than drm/kms driver calling drm_dev_register(). This leads to a
WARN().

The orientation property is known earlier. For example, some panels
parse the property through device tree during probe.

Add an API to return the property from panel to drm/kms driver, so the
drivers are able to call drm_connector_set_panel_orientation() before
drm_dev_register().

Suggested-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx>
Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
---
v3->v4: Add a blank line.
---
drivers/gpu/drm/drm_panel.c | 9 +++++++++
include/drm/drm_panel.h | 10 ++++++++++
2 files changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
index f634371c717a..e12056cfeca8 100644
--- a/drivers/gpu/drm/drm_panel.c
+++ b/drivers/gpu/drm/drm_panel.c
@@ -223,6 +223,15 @@ int drm_panel_get_modes(struct drm_panel *panel,
}
EXPORT_SYMBOL(drm_panel_get_modes);

+enum drm_panel_orientation drm_panel_get_orientation(struct drm_panel *panel)
+{
+ if (panel && panel->funcs && panel->funcs->get_orientation)
+ return panel->funcs->get_orientation(panel);
+
+ return DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
+}
+EXPORT_SYMBOL(drm_panel_get_orientation);
+
#ifdef CONFIG_OF
/**
* of_drm_find_panel - look up a panel using a device tree node
diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
index d279ee455f01..5dadbf3b0370 100644
--- a/include/drm/drm_panel.h
+++ b/include/drm/drm_panel.h
@@ -133,6 +133,15 @@ struct drm_panel_funcs {
* Allows panels to create panels-specific debugfs files.
*/
void (*debugfs_init)(struct drm_panel *panel, struct dentry *root);
+
+ /**
+ * @get_orientation:
+ *
+ * Return the panel orientation set by device tree or EDID.
+ *
+ * This function is optional.
+ */
+ enum drm_panel_orientation (*get_orientation)(struct drm_panel *panel);
};

/**
@@ -202,6 +211,7 @@ int drm_panel_enable(struct drm_panel *panel);
int drm_panel_disable(struct drm_panel *panel);

int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector);
+enum drm_panel_orientation drm_panel_get_orientation(struct drm_panel *panel);

#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
struct drm_panel *of_drm_find_panel(const struct device_node *np);
--
2.36.1.255.ge46751e96f-goog