[PATCH 4/4] drm/vkms: subclass CRTC state

[Haneen Mohammed]

Subclass CRTC state struct to enable storing driver's private
state. This patch only adds the base drm_crtc_state struct and
the atomic functions that handle it.

Signed-off-by: Haneen Mohammed <hamohammed.sa at gmail.com>
---
 drivers/gpu/drm/vkms/vkms_crtc.c | 55 ++++++++++++++++++++++++++++++--
 drivers/gpu/drm/vkms/vkms_drv.h  |  8 +++++
 2 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
index 84cc05506b09..56206437647d 100644
--- a/drivers/gpu/drm/vkms/vkms_crtc.c
+++ b/drivers/gpu/drm/vkms/vkms_crtc.c
@@ -10,13 +10,62 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc_helper.h>
 
+static void vkms_crtc_reset(struct drm_crtc *crtc)
+{
+	struct vkms_crtc_state *state = NULL;
+
+	if (crtc->state) {
+		state = container_of(crtc->state, struct vkms_crtc_state,
+				     base);
+		__drm_atomic_helper_crtc_destroy_state(crtc->state);
+		kfree(state);
+		crtc->state = NULL;
+	}
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return;
+
+	crtc->state = &state->base;
+	crtc->state->crtc = crtc;
+}
+
+static struct drm_crtc_state *
+vkms_crtc_duplicate_state(struct drm_crtc *crtc)
+{
+	struct vkms_crtc_state *state;
+
+	if (WARN_ON(!crtc->state))
+		return NULL;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return NULL;
+
+	__drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
+
+	return &state->base;
+}
+
+static void vkms_crtc_destroy_state(struct drm_crtc *crtc,
+				    struct drm_crtc_state *state)
+{
+	struct vkms_crtc_state *vkms_state;
+
+	vkms_state = container_of(state, struct vkms_crtc_state, base);
+
+	__drm_atomic_helper_crtc_destroy_state(state);
+	kfree(vkms_state);
+}
+
 static const struct drm_crtc_funcs vkms_crtc_funcs = {
 	.set_config             = drm_atomic_helper_set_config,
 	.destroy                = drm_crtc_cleanup,
 	.page_flip              = drm_atomic_helper_page_flip,
-	.reset                  = drm_atomic_helper_crtc_reset,
-	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
-	.atomic_destroy_state   = drm_atomic_helper_crtc_destroy_state,
+
+	.reset                  = vkms_crtc_reset,
+	.atomic_duplicate_state = vkms_crtc_duplicate_state,
+	.atomic_destroy_state   = vkms_crtc_destroy_state,
 };
 
 static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index d339a8108d85..61e367d32308 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -19,6 +19,14 @@ static const u32 vkms_formats[] = {
 	DRM_FORMAT_XRGB8888,
 };
 
+/**
+ * vkms_crtc_state - Driver specific CRTC state
+ * @base: base CRTC state
+ */
+struct vkms_crtc_state {
+	struct drm_crtc_state base;
+};
+
 struct vkms_output {
 	struct drm_crtc crtc;
 	struct drm_encoder encoder;
-- 
2.17.1