drm/vgem: Add a dummy platform device

The vgem driver is currently registered independent of any actual
device. Some usage of the dmabuf APIs require an actual device structure
to do anything. Register a dummy platform device for use with dmabuf.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1493923548-20878-2-git-send-email-labbott@redhat.com

diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c
index 9fee38a..d1d98af 100644 (file)
--- a/drivers/gpu/drm/vgem/vgem_drv.c
+++ b/drivers/gpu/drm/vgem/vgem_drv.c
@@ -42,6 +42,8 @@
 #define DRIVER_MAJOR   1
 #define DRIVER_MINOR   0
 
+static struct platform_device *vgem_platform;
+
 static void vgem_gem_free_object(struct drm_gem_object *obj)
 {
        struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj);
@@ -335,11 +337,20 @@ static int __init vgem_init(void)
        int ret;
 
        vgem_device = drm_dev_alloc(&vgem_driver, NULL);
-       if (IS_ERR(vgem_device)) {
-               ret = PTR_ERR(vgem_device);
+       if (IS_ERR(vgem_device))
+               return PTR_ERR(vgem_device);
+
+       vgem_platform = platform_device_register_simple("vgem",
+                                       -1, NULL, 0);
+
+       if (!vgem_platform) {
+               ret = -ENODEV;
                goto out;
        }
 
+       dma_coerce_mask_and_coherent(&vgem_platform->dev,
+                                       DMA_BIT_MASK(64));
+
        ret  = drm_dev_register(vgem_device, 0);
        if (ret)
                goto out_unref;
@@ -347,13 +358,15 @@ static int __init vgem_init(void)
        return 0;
 
 out_unref:
-       drm_dev_unref(vgem_device);
+       platform_device_unregister(vgem_platform);
 out:
+       drm_dev_unref(vgem_device);
        return ret;
 }
 
 static void __exit vgem_exit(void)
 {
+       platform_device_unregister(vgem_platform);
        drm_dev_unregister(vgem_device);
        drm_dev_unref(vgem_device);
 }