drm/panel: simple: Stop tracking prepared/enabled

As talked about in commit d2aacaf07395 ("drm/panel: Check for already
prepared/enabled in drm_panel"), we want to remove needless code from
panel drivers that was storing and double-checking the
prepared/enabled state. Even if someone was relying on the
double-check before, that double-check is now in the core and not
needed in individual drivers.

Acked-by: Linus Walleij <[e-mail]>
Acked-by: Maxime Ripard <[e-mail]>
Acked-by: Sui Jingfeng <[e-mail]>
Signed-off-by: Douglas Anderson <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/20240503143327.RFT.v2.26.I865be97dd393d6ae3c3a3cd1358c95fdbca0fe83@changeid

drivers/gpu/drm/panel/panel-simple.c

···
 
 struct panel_simple {
 	struct drm_panel base;
-	bool enabled;
-
-	bool prepared;
 
 	ktime_t unprepared_time;
 
···
 {
 	struct panel_simple *p = to_panel_simple(panel);
 
-	if (!p->enabled)
-		return 0;
-
 	if (p->desc->delay.disable)
 		msleep(p->desc->delay.disable);
-
-	p->enabled = false;
 
 	return 0;
 }
···
 
 static int panel_simple_unprepare(struct drm_panel *panel)
 {
-	struct panel_simple *p = to_panel_simple(panel);
 	int ret;
-
-	/* Unpreparing when already unprepared is a no-op */
-	if (!p->prepared)
-		return 0;
 
 	pm_runtime_mark_last_busy(panel->dev);
 	ret = pm_runtime_put_autosuspend(panel->dev);
 	if (ret < 0)
 		return ret;
-	p->prepared = false;
 
 	return 0;
 }
···
 
 static int panel_simple_prepare(struct drm_panel *panel)
 {
-	struct panel_simple *p = to_panel_simple(panel);
 	int ret;
-
-	/* Preparing when already prepared is a no-op */
-	if (p->prepared)
-		return 0;
 
 	ret = pm_runtime_get_sync(panel->dev);
 	if (ret < 0) {
 		pm_runtime_put_autosuspend(panel->dev);
 		return ret;
 	}
-
-	p->prepared = true;
 
 	return 0;
 }
···
 {
 	struct panel_simple *p = to_panel_simple(panel);
 
-	if (p->enabled)
-		return 0;
-
 	if (p->desc->delay.enable)
 		msleep(p->desc->delay.enable);
-
-	p->enabled = true;
 
 	return 0;
 }
···
 	if (!panel)
 		return -ENOMEM;
 
-	panel->enabled = false;
 	panel->desc = desc;
 
 	panel->supply = devm_regulator_get(dev, "power");