diff options
Diffstat (limited to 'drivers/gpu/drm/virtio/virtgpu_drm_bus.c')
| -rw-r--r-- | drivers/gpu/drm/virtio/virtgpu_drm_bus.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/drivers/gpu/drm/virtio/virtgpu_drm_bus.c b/drivers/gpu/drm/virtio/virtgpu_drm_bus.c index 757ca28ab93e..0887e0b64b9c 100644 --- a/drivers/gpu/drm/virtio/virtgpu_drm_bus.c +++ b/drivers/gpu/drm/virtio/virtgpu_drm_bus.c @@ -53,6 +53,37 @@ int drm_virtio_init(struct drm_driver *driver, struct virtio_device *vdev) 0, "virtiodrmfb"); + /* + * Normally the drm_dev_set_unique() call is done by core DRM. + * The following comment covers, why virtio cannot rely on it. + * + * Unlike the other virtual GPU drivers, virtio abstracts the + * underlying bus type by using struct virtio_device. + * + * Hence the dev_is_pci() check, used in core DRM, will fail + * and the unique returned will be the virtio_device "virtio0", + * while a "pci:..." one is required. + * + * A few other ideas were considered: + * - Extend the dev_is_pci() check [in drm_set_busid] to + * consider virtio. + * Seems like a bigger hack than what we have already. + * + * - Point drm_device::dev to the parent of the virtio_device + * Semantic changes: + * * Using the wrong device for i2c, framebuffer_alloc and + * prime import. + * Visual changes: + * * Helpers such as DRM_DEV_ERROR, dev_info, drm_printer, + * will print the wrong information. + * + * We could address the latter issues, by introducing + * drm_device::bus_dev, ... which would be used solely for this. + * + * So for the moment keep things as-is, with a bulky comment + * for the next person who feels like removing this + * drm_dev_set_unique() quirk. + */ snprintf(unique, sizeof(unique), "pci:%s", pname); ret = drm_dev_set_unique(dev, unique); if (ret) |