drm/panel: panel-innolux: set display off in innolux_panel_unprepare

[ Upstream commit 46f3ceaffa81e846677bca8668e0ad40e643cffd ]

Move mipi_dsi_dcs_set_display_off() from innolux_panel_disable()
to innolux_panel_unprepare(), so they are consistent with
innolux_panel_enable() and innolux_panel_prepare().

This also fixes some mode check and irq timeout issue in MTK dsi code.

Since some dsi code (e.g. mtk_dsi) have following call trace:
1. drm_panel_disable(), which calls innolux_panel_disable()
2. switch to cmd mode
3. drm_panel_unprepare(), which calls innolux_panel_unprepare()

However, mtk_dsi needs to be in cmd mode to be able to send commands
(e.g. mipi_dsi_dcs_set_display_off() and mipi_dsi_dcs_enter_sleep_mode()),
so we need these functions to be called after the switch to cmd mode happens,
i.e. in innolux_panel_unprepare.

Signed-off-by: Hsin-Yi, Wang <hsinyi@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190109065922.231753-1-hsinyi@chromium.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/gpu/drm/panel/panel-innolux-p079zca.c

@@ -70,18 +70,12 @@ static inline struct innolux_panel *to_innolux_panel(struct drm_panel *panel)
 static int innolux_panel_disable(struct drm_panel *panel)
 {
 	struct innolux_panel *innolux = to_innolux_panel(panel);
-	int err;
 
 	if (!innolux->enabled)
 		return 0;
 
 	backlight_disable(innolux->backlight);
 
-	err = mipi_dsi_dcs_set_display_off(innolux->link);
-	if (err < 0)
-		DRM_DEV_ERROR(panel->dev, "failed to set display off: %d\n",
-			      err);
-
 	innolux->enabled = false;
 
 	return 0;
@@ -95,6 +89,11 @@ static int innolux_panel_unprepare(struct drm_panel *panel)
 	if (!innolux->prepared)
 		return 0;
 
+	err = mipi_dsi_dcs_set_display_off(innolux->link);
+	if (err < 0)
+		DRM_DEV_ERROR(panel->dev, "failed to set display off: %d\n",
+			      err);
+
 	err = mipi_dsi_dcs_enter_sleep_mode(innolux->link);
 	if (err < 0) {
 		DRM_DEV_ERROR(panel->dev, "failed to enter sleep mode: %d\n",