drm/rockchip: dw_hdmi: add regulator support

The RK3568 has HDMI_TX_AVDD0V9 and HDMI_TX_AVDD_1V8 supply inputs needed
for the HDMI port. add support for these to the driver for boards which
have them supplied by switchable regulators.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Tested-by: Michael Riesch <michael.riesch@wolfvision.net>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220422072841.2206452-10-s.hauer@pengutronix.de

drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c

@@ -9,6 +9,7 @@
 #include <linux/platform_device.h>
 #include <linux/phy/phy.h>
 #include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
 
 #include <drm/bridge/dw_hdmi.h>
 #include <drm/drm_edid.h>
@@ -76,6 +77,8 @@ struct rockchip_hdmi {
 	struct clk *ref_clk;
 	struct clk *grf_clk;
 	struct dw_hdmi *hdmi;
+	struct regulator *avdd_0v9;
+	struct regulator *avdd_1v8;
 	struct phy *phy;
 };
 
@@ -226,6 +229,14 @@ static int rockchip_hdmi_parse_dt(struct rockchip_hdmi *hdmi)
 		return PTR_ERR(hdmi->grf_clk);
 	}
 
+	hdmi->avdd_0v9 = devm_regulator_get(hdmi->dev, "avdd-0v9");
+	if (IS_ERR(hdmi->avdd_0v9))
+		return PTR_ERR(hdmi->avdd_0v9);
+
+	hdmi->avdd_1v8 = devm_regulator_get(hdmi->dev, "avdd-1v8");
+	if (IS_ERR(hdmi->avdd_1v8))
+		return PTR_ERR(hdmi->avdd_1v8);
+
 	return 0;
 }
 
@@ -566,11 +577,23 @@ static int dw_hdmi_rockchip_bind(struct device *dev, struct device *master,
 		return ret;
 	}
 
+	ret = regulator_enable(hdmi->avdd_0v9);
+	if (ret) {
+		DRM_DEV_ERROR(hdmi->dev, "failed to enable avdd0v9: %d\n", ret);
+		goto err_avdd_0v9;
+	}
+
+	ret = regulator_enable(hdmi->avdd_1v8);
+	if (ret) {
+		DRM_DEV_ERROR(hdmi->dev, "failed to enable avdd1v8: %d\n", ret);
+		goto err_avdd_1v8;
+	}
+
 	ret = clk_prepare_enable(hdmi->ref_clk);
 	if (ret) {
 		DRM_DEV_ERROR(hdmi->dev, "Failed to enable HDMI reference clock: %d\n",
 			      ret);
-		return ret;
+		goto err_clk;
 	}
 
 	if (hdmi->chip_data == &rk3568_chip_data) {
@@ -594,10 +617,19 @@ static int dw_hdmi_rockchip_bind(struct device *dev, struct device *master,
 	 */
 	if (IS_ERR(hdmi->hdmi)) {
 		ret = PTR_ERR(hdmi->hdmi);
-		drm_encoder_cleanup(encoder);
-		clk_disable_unprepare(hdmi->ref_clk);
+		goto err_bind;
 	}
 
+	return 0;
+
+err_bind:
+	drm_encoder_cleanup(encoder);
+	clk_disable_unprepare(hdmi->ref_clk);
+err_clk:
+	regulator_disable(hdmi->avdd_1v8);
+err_avdd_1v8:
+	regulator_disable(hdmi->avdd_0v9);
+err_avdd_0v9:
 	return ret;
 }
 
@@ -608,6 +640,9 @@ static void dw_hdmi_rockchip_unbind(struct device *dev, struct device *master,
 
 	dw_hdmi_unbind(hdmi->hdmi);
 	clk_disable_unprepare(hdmi->ref_clk);
+
+	regulator_disable(hdmi->avdd_1v8);
+	regulator_disable(hdmi->avdd_0v9);
 }
 
 static const struct component_ops dw_hdmi_rockchip_ops = {