drm/vkms: Switch to dynamic allocation for CRTC

A specific allocation for the CRTC is not strictly necessary at this
point, but in order to implement dynamic configuration of VKMS (configFS),
it will be easier to have one allocation per CRTC.

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250117-b4-vkms-allocated-v4-3-8ec8fd21aaf6@bootlin.com
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>

1 files changed, 12 insertions, 10 deletions

diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
index 21ca975e424d..22f0d678af3a 100644
--- a/drivers/gpu/drm/vkms/vkms_output.c
+++ b/drivers/gpu/drm/vkms/vkms_output.c
@@ -30,11 +30,10 @@ static const struct drm_connector_helper_funcs vkms_conn_helper_funcs = {
 
 int vkms_output_init(struct vkms_device *vkmsdev)
 {
-	struct vkms_output *output = &vkmsdev->output;
 	struct drm_device *dev = &vkmsdev->drm;
 	struct drm_connector *connector;
 	struct drm_encoder *encoder;
-	struct drm_crtc *crtc = &output->crtc;
+	struct vkms_output *output;
 	struct vkms_plane *primary, *overlay, *cursor = NULL;
 	int ret;
 	int writeback;
@@ -56,9 +55,12 @@ int vkms_output_init(struct vkms_device *vkmsdev)
 			return PTR_ERR(cursor);
 	}
 
-	ret = vkms_crtc_init(dev, crtc, &primary->base, &cursor->base);
-	if (ret)
-		return ret;
+	output = vkms_crtc_init(dev, &primary->base,
+				cursor ? &cursor->base : NULL);
+	if (IS_ERR(output)) {
+		DRM_ERROR("Failed to allocate CRTC\n");
+		return PTR_ERR(output);
+	}
 
 	if (vkmsdev->config->overlay) {
 		for (n = 0; n < NUM_OVERLAY_PLANES; n++) {
@@ -67,7 +69,7 @@ int vkms_output_init(struct vkms_device *vkmsdev)
 				DRM_DEV_ERROR(dev->dev, "Failed to init vkms plane\n");
 				return PTR_ERR(overlay);
 			}
-			overlay->base.possible_crtcs = drm_crtc_mask(crtc);
+			overlay->base.possible_crtcs = drm_crtc_mask(&output->crtc);
 		}
 	}
 
@@ -97,23 +99,23 @@ int vkms_output_init(struct vkms_device *vkmsdev)
 		DRM_ERROR("Failed to init encoder\n");
 		return ret;
 	}
-	encoder->possible_crtcs = drm_crtc_mask(crtc);
+	encoder->possible_crtcs = drm_crtc_mask(&output->crtc);
 
+	/* Attach the encoder and the connector */
 	ret = drm_connector_attach_encoder(connector, encoder);
 	if (ret) {
 		DRM_ERROR("Failed to attach connector to encoder\n");
 		return ret;
 	}
 
+	/* Initialize the writeback component */
 	if (vkmsdev->config->writeback) {
-		writeback = vkms_enable_writeback_connector(vkmsdev, crtc);
+		writeback = vkms_enable_writeback_connector(vkmsdev, output);
 		if (writeback)
 			DRM_ERROR("Failed to init writeback connector\n");
 	}
 
 	drm_mode_config_reset(dev);
 
-	return 0;
-
 	return ret;
 }