drm/omap: panel-dsi-cm: use bulk regulator API

Use bulk regulator API to simplify the code. This also switches
from _optional variant to normal variant, which will provide a
dummy regulator (i.e. if some always-enabled regulator is not
described in DT).
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201215104657.802264-23-tomi.valkeinen@ti.com

drivers/gpu/drm/omapdrm/displays/panel-dsi-cm.c

@@ -32,6 +32,8 @@
 #define DCS_GET_ID2		0xdb
 #define DCS_GET_ID3		0xdc
 
+#define DCS_REGULATOR_SUPPLY_NUM 2
+
 struct panel_drv_data {
 	struct mipi_dsi_device *dsi;
 
@@ -54,8 +56,7 @@ struct panel_drv_data {
 	struct gpio_desc *reset_gpio;
 	struct gpio_desc *ext_te_gpio;
 
-	struct regulator *vpnl;
-	struct regulator *vddi;
+	struct regulator_bulk_data supplies[DCS_REGULATOR_SUPPLY_NUM];
 
 	bool use_dsi_backlight;
 
@@ -556,28 +557,16 @@ static int dsicm_power_on(struct panel_drv_data *ddata)
 		.lp_clk_max = 10000000,
 	};
 
-	if (ddata->vpnl) {
-		r = regulator_enable(ddata->vpnl);
-		if (r) {
-			dev_err(&ddata->dsi->dev,
-				"failed to enable VPNL: %d\n", r);
-			return r;
-		}
-	}
-
-	if (ddata->vddi) {
-		r = regulator_enable(ddata->vddi);
-		if (r) {
-			dev_err(&ddata->dsi->dev,
-				"failed to enable VDDI: %d\n", r);
-			goto err_vpnl;
-		}
+	r = regulator_bulk_enable(ARRAY_SIZE(ddata->supplies), ddata->supplies);
+	if (r) {
+		dev_err(&ddata->dsi->dev, "failed to enable supplies: %d\n", r);
+		return r;
 	}
 
 	r = src->ops->dsi.set_config(src, &dsi_config);
 	if (r) {
 		dev_err(&ddata->dsi->dev, "failed to configure DSI\n");
-		goto err_vddi;
+		goto err_regulators;
 	}
 
 	src->ops->enable(src);
@@ -636,12 +625,10 @@ static int dsicm_power_on(struct panel_drv_data *ddata)
 	dsicm_hw_reset(ddata);
 
 	src->ops->dsi.disable(src, true, false);
-err_vddi:
-	if (ddata->vddi)
-		regulator_disable(ddata->vddi);
-err_vpnl:
-	if (ddata->vpnl)
-		regulator_disable(ddata->vpnl);
+err_regulators:
+	r = regulator_bulk_disable(ARRAY_SIZE(ddata->supplies), ddata->supplies);
+	if (r)
+		dev_err(&ddata->dsi->dev, "failed to disable supplies: %d\n", r);
 
 	return r;
 }
@@ -665,10 +652,9 @@ static void dsicm_power_off(struct panel_drv_data *ddata)
 
 	src->ops->dsi.disable(src, true, false);
 
-	if (ddata->vddi)
-		regulator_disable(ddata->vddi);
-	if (ddata->vpnl)
-		regulator_disable(ddata->vpnl);
+	r = regulator_bulk_disable(ARRAY_SIZE(ddata->supplies), ddata->supplies);
+	if (r)
+		dev_err(&ddata->dsi->dev, "failed to disable supplies: %d\n", r);
 
 	ddata->enabled = false;
 }
@@ -972,21 +958,12 @@ static int dsicm_probe_of(struct mipi_dsi_device *dsi)
 	ddata->height_mm = 0;
 	of_property_read_u32(node, "height-mm", &ddata->height_mm);
 
-	ddata->vpnl = devm_regulator_get_optional(&dsi->dev, "vpnl");
-	if (IS_ERR(ddata->vpnl)) {
-		err = PTR_ERR(ddata->vpnl);
-		if (err == -EPROBE_DEFER)
-			return err;
-		ddata->vpnl = NULL;
-	}
-
-	ddata->vddi = devm_regulator_get_optional(&dsi->dev, "vddi");
-	if (IS_ERR(ddata->vddi)) {
-		err = PTR_ERR(ddata->vddi);
-		if (err == -EPROBE_DEFER)
-			return err;
-		ddata->vddi = NULL;
-	}
+	ddata->supplies[0].supply = "vpnl";
+	ddata->supplies[1].supply = "vddi";
+	err = devm_regulator_bulk_get(&dsi->dev, ARRAY_SIZE(ddata->supplies),
+				      ddata->supplies);
+	if (err)
+		return err;
 
 	backlight = devm_of_find_backlight(&dsi->dev);
 	if (IS_ERR(backlight))