kms/connector: Make property ID fetching more declarative

Instead of relatively verbosely going through the DRM properties finding
the properties we care about and saving their ID's, add a more
declarative way to fetch property metadata. This'll allow for fetching
more property IDs with relatively less code, which will be useful for
the atomic backend.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1488>

src/backends/native/meta-kms-connector.c

@@ -30,6 +30,20 @@
 #include "backends/native/meta-kms-mode-private.h"
 #include "backends/native/meta-kms-update-private.h"
 
+typedef enum _MetaKmsConnectorProp
+{
+  META_KMS_CONNECTOR_PROP_DPMS = 0,
+  META_KMS_CONNECTOR_PROP_UNDERSCAN,
+  META_KMS_CONNECTOR_PROP_UNDERSCAN_HBORDER,
+  META_KMS_CONNECTOR_PROP_UNDERSCAN_VBORDER,
+  META_KMS_CONNECTOR_N_PROPS
+} MetaKmsConnectorProp;
+
+typedef struct _MetaKmsConnectorPropTable
+{
+  MetaKmsProp props[META_KMS_CONNECTOR_N_PROPS];
+} MetaKmsConnectorPropTable;
+
 struct _MetaKmsConnector
 {
   GObject parent;
@@ -43,10 +57,8 @@ struct _MetaKmsConnector
 
   MetaKmsConnectorState *current_state;
 
-  uint32_t dpms_prop_id;
+  MetaKmsConnectorPropTable prop_table;
-  uint32_t underscan_prop_id;
+
-  uint32_t underscan_hborder_prop_id;
-  uint32_t underscan_vborder_prop_id;
   uint32_t edid_blob_id;
   uint32_t tile_blob_id;
 };
@@ -64,9 +76,12 @@ meta_kms_connector_update_set_dpms_state (MetaKmsConnector *connector,
                                           MetaKmsUpdate    *update,
                                           uint64_t          state)
 {
+  uint32_t prop_id;
+
+  prop_id = connector->prop_table.props[META_KMS_CONNECTOR_PROP_DPMS].prop_id;
   meta_kms_update_set_connector_property (update,
                                           connector,
-                                          connector->dpms_prop_id,
+                                          prop_id,
                                           state);
 }
 
@@ -76,17 +91,29 @@ meta_kms_connector_set_underscanning (MetaKmsConnector *connector,
                                       uint64_t          hborder,
                                       uint64_t          vborder)
 {
+  MetaKmsProp *props = connector->prop_table.props;
+  uint32_t underscan_prop_id;
+  uint32_t underscan_hborder_prop_id;
+  uint32_t underscan_vborder_prop_id;
+
+  underscan_prop_id =
+    props[META_KMS_CONNECTOR_PROP_UNDERSCAN].prop_id;
+  underscan_hborder_prop_id =
+    props[META_KMS_CONNECTOR_PROP_UNDERSCAN_HBORDER].prop_id;
+  underscan_vborder_prop_id =
+    props[META_KMS_CONNECTOR_PROP_UNDERSCAN_VBORDER].prop_id;
+
   meta_kms_update_set_connector_property (update,
                                           connector,
-                                          connector->underscan_prop_id,
+                                          underscan_prop_id,
                                           1);
   meta_kms_update_set_connector_property (update,
                                           connector,
-                                          connector->underscan_hborder_prop_id,
+                                          underscan_hborder_prop_id,
                                           hborder);
   meta_kms_update_set_connector_property (update,
                                           connector,
-                                          connector->underscan_vborder_prop_id,
+                                          underscan_vborder_prop_id,
                                           vborder);
 }
 
@@ -94,9 +121,13 @@ void
 meta_kms_connector_unset_underscanning (MetaKmsConnector *connector,
                                         MetaKmsUpdate    *update)
 {
+  MetaKmsProp *props = connector->prop_table.props;
+  uint32_t underscan_prop_id;
+
+  underscan_prop_id = props[META_KMS_CONNECTOR_PROP_UNDERSCAN].prop_id;
   meta_kms_update_set_connector_property (update,
                                           connector,
-                                          connector->underscan_prop_id,
+                                          underscan_prop_id,
                                           0);
 }
 
@@ -144,7 +175,12 @@ meta_kms_connector_get_current_state (MetaKmsConnector *connector)
 gboolean
 meta_kms_connector_is_underscanning_supported (MetaKmsConnector *connector)
 {
-  return connector->underscan_prop_id != 0;
+  uint32_t underscan_prop_id;
+
+  underscan_prop_id =
+    connector->prop_table.props[META_KMS_CONNECTOR_PROP_UNDERSCAN].prop_id;
+
+  return underscan_prop_id != 0;
 }
 
 static void
@@ -543,38 +579,42 @@ meta_kms_connector_predict_state (MetaKmsConnector *connector,
 }
 
 static void
-find_property_ids (MetaKmsConnector  *connector,
+init_properties (MetaKmsConnector  *connector,
-                   MetaKmsImplDevice *impl_device,
+                 MetaKmsImplDevice *impl_device,
-                   drmModeConnector  *drm_connector)
+                 drmModeConnector  *drm_connector)
 {
-  int fd;
+  MetaKmsConnectorPropTable *prop_table = &connector->prop_table;
-  int i;
 
-  fd = meta_kms_impl_device_get_fd (impl_device);
+  *prop_table = (MetaKmsConnectorPropTable) {
-
+    .props = {
-  for (i = 0; i < drm_connector->count_props; i++)
+      [META_KMS_CONNECTOR_PROP_DPMS] =
-    {
+        {
-      drmModePropertyPtr prop;
+          .name = "DPMS",
-
+          .type = DRM_MODE_PROP_ENUM,
-      prop = drmModeGetProperty (fd, drm_connector->props[i]);
+        },
-      if (!prop)
+      [META_KMS_CONNECTOR_PROP_UNDERSCAN] =
-        continue;
+        {
-
+          .name = "underscan",
-      if ((prop->flags & DRM_MODE_PROP_ENUM) &&
+          .type = DRM_MODE_PROP_ENUM,
-          strcmp (prop->name, "DPMS") == 0)
+        },
-        connector->dpms_prop_id = prop->prop_id;
+      [META_KMS_CONNECTOR_PROP_UNDERSCAN_HBORDER] =
-      else if ((prop->flags & DRM_MODE_PROP_ENUM) &&
+        {
-               strcmp (prop->name, "underscan") == 0)
+          .name = "underscan hborder",
-        connector->underscan_prop_id = prop->prop_id;
+          .type = DRM_MODE_PROP_RANGE,
-      else if ((prop->flags & DRM_MODE_PROP_RANGE) &&
+        },
-               strcmp (prop->name, "underscan hborder") == 0)
+      [META_KMS_CONNECTOR_PROP_UNDERSCAN_VBORDER] =
-        connector->underscan_hborder_prop_id = prop->prop_id;
+        {
-      else if ((prop->flags & DRM_MODE_PROP_RANGE) &&
+          .name = "underscan vborder",
-               strcmp (prop->name, "underscan vborder") == 0)
+          .type = DRM_MODE_PROP_RANGE,
-        connector->underscan_vborder_prop_id = prop->prop_id;
+        },
-
-      drmModeFreeProperty (prop);
     }
+  };
+
+  meta_kms_impl_device_init_prop_table (impl_device,
+                                        drm_connector->props,
+                                        drm_connector->count_props,
+                                        connector->prop_table.props,
+                                        META_KMS_CONNECTOR_N_PROPS);
 }
 
 static char *
@@ -633,7 +673,7 @@ meta_kms_connector_new (MetaKmsImplDevice *impl_device,
   connector->type_id = drm_connector->connector_type_id;
   connector->name = make_connector_name (drm_connector);
 
-  find_property_ids (connector, impl_device, drm_connector);
+  init_properties (connector, impl_device, drm_connector);
 
   meta_kms_connector_read_state (connector, impl_device,
                                  drm_connector,

src/backends/native/meta-kms-impl-device.c

@@ -337,6 +337,69 @@ meta_kms_impl_device_add_fake_plane (MetaKmsImplDevice *impl_device,
   return plane;
 }
 
+static MetaKmsProp *
+find_prop (MetaKmsProp *props,
+           int          n_props,
+           const char  *name)
+{
+  int i;
+
+  for (i = 0; i < n_props; i++)
+    {
+      MetaKmsProp *prop = &props[i];
+
+      g_warn_if_fail (prop->name);
+
+      if (g_strcmp0 (prop->name, name) == 0)
+        return prop;
+    }
+
+  return NULL;
+}
+
+void
+meta_kms_impl_device_init_prop_table (MetaKmsImplDevice *impl_device,
+                                      uint32_t          *drm_props,
+                                      int                n_drm_props,
+                                      MetaKmsProp       *props,
+                                      int                n_props)
+{
+  int fd;
+  uint32_t i;
+
+  fd = meta_kms_impl_device_get_fd (impl_device);
+
+  for (i = 0; i < n_drm_props; i++)
+    {
+      drmModePropertyRes *drm_prop;
+      MetaKmsProp *prop;
+
+      drm_prop = drmModeGetProperty (fd, drm_props[i]);
+      if (!drm_prop)
+        continue;
+
+      prop = find_prop (props, n_props, drm_prop->name);
+      if (!prop)
+        {
+          drmModeFreeProperty (drm_prop);
+          continue;
+        }
+
+      if (!(drm_prop->flags & prop->type))
+        {
+          g_warning ("DRM property '%s' (%u) had unexpected flags (0x%x), "
+                     "ignoring",
+                     drm_prop->name, drm_props[i], drm_prop->flags);
+          drmModeFreeProperty (drm_prop);
+          continue;
+        }
+
+      prop->prop_id = drm_props[i];
+
+      drmModeFreeProperty (drm_prop);
+    }
+}
+
 static void
 init_planes (MetaKmsImplDevice *impl_device)
 {

src/backends/native/meta-kms-impl-device.h

@@ -35,6 +35,14 @@ typedef struct _MetaKmsDeviceCaps
   uint64_t cursor_height;
 } MetaKmsDeviceCaps;
 
+typedef struct _MetaKmsProp
+{
+  const char *name;
+  uint32_t type;
+
+  uint32_t prop_id;
+} MetaKmsProp;
+
 #define META_TYPE_KMS_IMPL_DEVICE (meta_kms_impl_device_get_type ())
 G_DECLARE_FINAL_TYPE (MetaKmsImplDevice, meta_kms_impl_device,
                       META, KMS_IMPL_DEVICE,
@@ -77,6 +85,12 @@ MetaKmsPlane * meta_kms_impl_device_add_fake_plane (MetaKmsImplDevice *impl_devi
                                                     MetaKmsPlaneType   plane_type,
                                                     MetaKmsCrtc       *crtc);
 
+void meta_kms_impl_device_init_prop_table (MetaKmsImplDevice *impl_device,
+                                           uint32_t          *drm_props,
+                                           int                n_drm_props,
+                                           MetaKmsProp       *props,
+                                           int                n_props);
+
 int meta_kms_impl_device_close (MetaKmsImplDevice *impl_device);
 
 MetaKmsImplDevice * meta_kms_impl_device_new (MetaKmsDevice  *device,