[RFC 2/9] drm: add object property type

[Rob Clark]

From: Rob Clark <rob at ti.com>

An object property is an id (idr) for a drm mode object.  This
will allow a property to be used set/get a framebuffer, CRTC, etc.
---
 drivers/gpu/drm/drm_crtc.c |   28 ++++++++++++++++++++++++++++
 include/drm/drm_crtc.h     |    5 +++++
 include/drm/drm_mode.h     |    1 +
 3 files changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 40a3f21..12829de 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -2859,6 +2859,23 @@ struct drm_property *drm_property_create_range(struct drm_device *dev, int flags
 }
 EXPORT_SYMBOL(drm_property_create_range);
 
+struct drm_property *drm_property_create_object(struct drm_device *dev,
+					 int flags, const char *name, uint32_t type)
+{
+	struct drm_property *property;
+
+	flags |= DRM_MODE_PROP_OBJECT;
+
+	property = drm_property_create(dev, flags, name, 1);
+	if (!property)
+		return NULL;
+
+	property->values[0] = type;
+
+	return property;
+}
+EXPORT_SYMBOL(drm_property_create_object);
+
 int drm_property_add_enum(struct drm_property *property, int index,
 			  uint64_t value, const char *name)
 {
@@ -3203,6 +3220,9 @@ static bool drm_property_change_is_valid(struct drm_property *property,
 		for (i = 0; i < property->num_values; i++)
 			valid_mask |= (1ULL << property->values[i]);
 		return !(value & ~valid_mask);
+	} else if (property->flags & DRM_MODE_PROP_OBJECT) {
+		/* check for valid object or zero happens elsewhere */
+		return true;
 	} else {
 		int i;
 		for (i = 0; i < property->num_values; i++)
@@ -3280,6 +3300,14 @@ static int drm_mode_set_obj_prop(struct drm_device *dev,
 		struct drm_property *property, uint64_t value)
 {
 	if (drm_property_change_is_valid(property, value)) {
+		/* a zero value for an object property translates to null: */
+		if ((property->flags & DRM_MODE_PROP_OBJECT) && value) {
+			struct drm_mode_object *obj =
+					drm_mode_object_find(dev, value, property->values[0]);
+			if (!obj)
+				return -EINVAL;
+			value = VOID2U64(obj);
+		}
 		switch (obj->type) {
 		case DRM_MODE_OBJECT_CONNECTOR:
 			return drm_mode_connector_set_obj_prop(obj_to_connector(obj),
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index a609190..92df2f4 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -61,6 +61,9 @@ struct drm_object_properties {
 	uint64_t values[DRM_OBJECT_MAX_PROPERTY];
 };
 
+#define U642VOID(x) ((void *)(unsigned long)(x))
+#define VOID2U64(x) ((uint64_t)(unsigned long)(x))
+
 /*
  * Note on terminology:  here, for brevity and convenience, we refer to connector
  * control chips as 'CRTCs'.  They can control any type of connector, VGA, LVDS,
@@ -955,6 +958,8 @@ struct drm_property *drm_property_create_bitmask(struct drm_device *dev,
 struct drm_property *drm_property_create_range(struct drm_device *dev, int flags,
 					 const char *name,
 					 uint64_t min, uint64_t max);
+struct drm_property *drm_property_create_object(struct drm_device *dev,
+					 int flags, const char *name, uint32_t type);
 extern void drm_property_destroy(struct drm_device *dev, struct drm_property *property);
 extern int drm_property_add_enum(struct drm_property *property, int index,
 				 uint64_t value, const char *name);
diff --git a/include/drm/drm_mode.h b/include/drm/drm_mode.h
index 5581980..cee4c53 100644
--- a/include/drm/drm_mode.h
+++ b/include/drm/drm_mode.h
@@ -231,6 +231,7 @@ struct drm_mode_get_connector {
 #define DRM_MODE_PROP_ENUM	(1<<3) /* enumerated type with text strings */
 #define DRM_MODE_PROP_BLOB	(1<<4)
 #define DRM_MODE_PROP_BITMASK	(1<<5) /* bitmask of enumerated types */
+#define DRM_MODE_PROP_OBJECT	(1<<6) /* drm mode object */
 
 struct drm_mode_property_enum {
 	__u64 value;
-- 
1.7.9.5