drm/exynos/mixer: fix mode validation code

Mode limitation checked in mixer driver affects only older HW.
Mixer in Exynos542x has no such limitations. While at it patch changes
validation callback to recently introduced mode_valid which is more
suitable for the check. Additionally little cleanup is performed.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_mixer.c

@@ -1040,26 +1040,24 @@ static void mixer_disable(struct exynos_drm_crtc *crtc)
 	clear_bit(MXR_BIT_POWERED, &ctx->flags);
 }
 
-/* Only valid for Mixer version 16.0.33.0 */
-static int mixer_atomic_check(struct exynos_drm_crtc *crtc,
-		       struct drm_crtc_state *state)
+static int mixer_mode_valid(struct exynos_drm_crtc *crtc,
+		const struct drm_display_mode *mode)
 {
-	struct drm_display_mode *mode = &state->adjusted_mode;
-	u32 w, h;
+	struct mixer_context *ctx = crtc->ctx;
+	u32 w = mode->hdisplay, h = mode->vdisplay;
 
-	w = mode->hdisplay;
-	h = mode->vdisplay;
+	DRM_DEBUG_KMS("xres=%d, yres=%d, refresh=%d, intl=%d\n", w, h,
+		mode->vrefresh, !!(mode->flags & DRM_MODE_FLAG_INTERLACE));
 
-	DRM_DEBUG_KMS("xres=%d, yres=%d, refresh=%d, intl=%d\n",
-		mode->hdisplay, mode->vdisplay, mode->vrefresh,
-		(mode->flags & DRM_MODE_FLAG_INTERLACE) ? 1 : 0);
+	if (ctx->mxr_ver == MXR_VER_128_0_0_184)
+		return MODE_OK;
 
 	if ((w >= 464 && w <= 720 && h >= 261 && h <= 576) ||
-		(w >= 1024 && w <= 1280 && h >= 576 && h <= 720) ||
-		(w >= 1664 && w <= 1920 && h >= 936 && h <= 1080))
-		return 0;
+	    (w >= 1024 && w <= 1280 && h >= 576 && h <= 720) ||
+	    (w >= 1664 && w <= 1920 && h >= 936 && h <= 1080))
+		return MODE_OK;
 
-	return -EINVAL;
+	return MODE_BAD;
 }
 
 static const struct exynos_drm_crtc_ops mixer_crtc_ops = {
@@ -1071,7 +1069,7 @@ static const struct exynos_drm_crtc_ops mixer_crtc_ops = {
 	.update_plane		= mixer_update_plane,
 	.disable_plane		= mixer_disable_plane,
 	.atomic_flush		= mixer_atomic_flush,
-	.atomic_check		= mixer_atomic_check,
+	.mode_valid		= mixer_mode_valid,
 };
 
 static const struct mixer_drv_data exynos5420_mxr_drv_data = {