drm/stm: ltdc: remove call of pm-runtime functions

It is not necessary to suspend or stop the ltdc clocks
to modify the pixel clock.
Signed-off-by: Yannick Fertre <yannick.fertre@st.com>
Acked-by: Philippe Cornu <philippe.cornu@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200701120402.6444-1-yannick.fertre@st.com

drivers/gpu/drm/stm/ltdc.c

@@ -503,15 +503,7 @@ static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
 				 struct drm_display_mode *adjusted_mode)
 {
 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
-	struct drm_device *ddev = crtc->dev;
 	int rate = mode->clock * 1000;
-	bool runtime_active;
-	int ret;
-
-	runtime_active = pm_runtime_active(ddev->dev);
-
-	if (runtime_active)
-		pm_runtime_put_sync(ddev->dev);
 
 	if (clk_set_rate(ldev->pixel_clk, rate) < 0) {
 		DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate);
@@ -520,14 +512,6 @@ static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
 
 	adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000;
 
-	if (runtime_active) {
-		ret = pm_runtime_get_sync(ddev->dev);
-		if (ret) {
-			DRM_ERROR("Failed to fixup mode, cannot get sync\n");
-			return false;
-		}
-	}
-
 	DRM_DEBUG_DRIVER("requested clock %dkHz, adjusted clock %dkHz\n",
 			 mode->clock, adjusted_mode->clock);