drm/exynos: exynos7_drm_decon: fix uninitialized crtc reference in functions

Modify the functions to accept a pointer to struct decon_context
instead.

Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

Author: Kaustabh Chakraborty

drivers/gpu/drm/exynos/exynos7_drm_decon.c

@@ -81,10 +81,8 @@ static const enum drm_plane_type decon_win_types[WINDOWS_NR] = {
 	DRM_PLANE_TYPE_CURSOR,
 };
 
-static void decon_wait_for_vblank(struct exynos_drm_crtc *crtc)
+static void decon_wait_for_vblank(struct decon_context *ctx)
 {
-	struct decon_context *ctx = crtc->ctx;
-
 	if (ctx->suspended)
 		return;
 
@@ -100,9 +98,8 @@ static void decon_wait_for_vblank(struct exynos_drm_crtc *crtc)
 		DRM_DEV_DEBUG_KMS(ctx->dev, "vblank wait timed out.\n");
 }
 
-static void decon_clear_channels(struct exynos_drm_crtc *crtc)
+static void decon_clear_channels(struct decon_context *ctx)
 {
-	struct decon_context *ctx = crtc->ctx;
 	unsigned int win, ch_enabled = 0;
 
 	/* Check if any channel is enabled. */
@@ -118,15 +115,15 @@ static void decon_clear_channels(struct exynos_drm_crtc *crtc)
 
 	/* Wait for vsync, as disable channel takes effect at next vsync */
 	if (ch_enabled)
-		decon_wait_for_vblank(ctx->crtc);
+		decon_wait_for_vblank(ctx);
 }
 
 static int decon_ctx_initialize(struct decon_context *ctx,
 			struct drm_device *drm_dev)
 {
 	ctx->drm_dev = drm_dev;
 
-	decon_clear_channels(ctx->crtc);
+	decon_clear_channels(ctx);
 
 	return exynos_drm_register_dma(drm_dev, ctx->dev, &ctx->dma_priv);
 }