[mutter] gpu/kms: Add identifier

[Jonas Ådahl <jadahl src gnome org>]

commit 91d4f30ebd96b6fdf486c367a83a706a6bac061c
Author: Emilio Pozuelo Monfort <emilio pozuelo collabora co uk>
Date:   Thu Oct 11 16:12:53 2018 +0200

    gpu/kms: Add identifier
    
    We need a device unique id in order to uniquely identify an output,
    which will use a (device, connector) pair.

 src/backends/native/meta-gpu-kms.c | 10 ++++++++++
 src/backends/native/meta-gpu-kms.h |  3 +++
 2 files changed, 13 insertions(+)
---
diff --git a/src/backends/native/meta-gpu-kms.c b/src/backends/native/meta-gpu-kms.c
index 57582f699..b651a70e5 100644
--- a/src/backends/native/meta-gpu-kms.c
+++ b/src/backends/native/meta-gpu-kms.c
@@ -59,6 +59,7 @@ struct _MetaGpuKms
 {
   MetaGpu parent;
 
+  uint32_t id;
   int fd;
   char *file_path;
   GSource *source;
@@ -378,6 +379,12 @@ meta_gpu_kms_get_fd (MetaGpuKms *gpu_kms)
   return gpu_kms->fd;
 }
 
+uint32_t
+meta_gpu_kms_get_id (MetaGpuKms *gpu_kms)
+{
+  return gpu_kms->id;
+}
+
 const char *
 meta_gpu_kms_get_file_path (MetaGpuKms *gpu_kms)
 {
@@ -889,7 +896,10 @@ meta_gpu_kms_finalize (GObject *object)
 static void
 meta_gpu_kms_init (MetaGpuKms *gpu_kms)
 {
+  static uint32_t id = 0;
+
   gpu_kms->fd = -1;
+  gpu_kms->id = ++id;
 }
 
 static void
diff --git a/src/backends/native/meta-gpu-kms.h b/src/backends/native/meta-gpu-kms.h
index 5f77f191a..349db2990 100644
--- a/src/backends/native/meta-gpu-kms.h
+++ b/src/backends/native/meta-gpu-kms.h
@@ -2,6 +2,7 @@
 
 /*
  * Copyright (C) 2017 Red Hat
+ * Copyright (C) 2018 DisplayLink (UK) Ltd.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -71,6 +72,8 @@ gboolean meta_gpu_kms_wait_for_flip (MetaGpuKms *gpu_kms,
 
 int meta_gpu_kms_get_fd (MetaGpuKms *gpu_kms);
 
+uint32_t meta_gpu_kms_get_id (MetaGpuKms *gpu_kms);
+
 const char * meta_gpu_kms_get_file_path (MetaGpuKms *gpu_kms);
 
 void meta_gpu_kms_get_max_buffer_size (MetaGpuKms *gpu_kms,