[PATCH v3 02/16] drm/vkms: Add a validation function for vkms configuration

[Louis Chauvet <louis.chauvet@bootlin.com>]

As the configuration will be used by userspace, add a validator to avoid
creating a broken DRM device

Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
---
 drivers/gpu/drm/vkms/vkms_config.c |  6 ++++++
 drivers/gpu/drm/vkms/vkms_config.h | 13 +++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
index 76355174a6ca54b880218c2bd458c8339a3dabaa..8d5c1429e6e196ef46c95c6ae73330bc4be2be39 100644
--- a/drivers/gpu/drm/vkms/vkms_config.c
+++ b/drivers/gpu/drm/vkms/vkms_config.c
@@ -24,6 +24,12 @@ void vkms_config_destroy(struct vkms_config *config)
 }
 EXPORT_SYMBOL_IF_KUNIT(vkms_config_destroy);
 
+bool vkms_config_is_valid(struct vkms_config *config)
+{
+	return true;
+}
+EXPORT_SYMBOL_IF_KUNIT(vkms_config_is_valid);
+
 static int vkms_config_show(struct seq_file *m, void *data)
 {
 	struct drm_debugfs_entry *entry = m->private;
diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
index b284831738743f6d7c452be03f917a7d3975d173..df571dd67352ca90fb47bd937fb9f11ceb95fcb2 100644
--- a/drivers/gpu/drm/vkms/vkms_config.h
+++ b/drivers/gpu/drm/vkms/vkms_config.h
@@ -29,4 +29,17 @@ void vkms_config_register_debugfs(struct vkms_device *vkms_device);
 struct vkms_config *vkms_config_create(void);
 void vkms_config_destroy(struct vkms_config *config);
 
+/**
+ * vkms_config_is_valid() - Validate a configuration
+ *
+ * Check if all the property defined in the configuration are valids. This will return false for
+ * example if:
+ * - no or many primary planes are present;
+ * - the default rotation of a plane is not in its supported rotation;
+ * - a CRTC don't have any encoder...
+ *
+ * @vkms_config: Configuration to validate
+ */
+bool vkms_config_is_valid(struct vkms_config *vkms_config);
+
 #endif //_VKMS_CONFIG_H

-- 
2.47.1