drm/exynos: dsi: add runtime pm support

This patch adds runtime pm interfaces to dsi driver.

Each sub driver should control not only its own clocks and
regulator but also its power domain.

For this, it removes existing exynos_dsi_poweron/poweroff interfaces
and uses runtime pm interfaces instead.
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_drm_dsi.c

@@ -1458,66 +1458,6 @@ static const struct mipi_dsi_host_ops exynos_dsi_ops = {
 	.transfer = exynos_dsi_host_transfer,
 };
 
-static int exynos_dsi_poweron(struct exynos_dsi *dsi)
-{
-	struct exynos_dsi_driver_data *driver_data = dsi->driver_data;
-	int ret, i;
-
-	ret = regulator_bulk_enable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
-	if (ret < 0) {
-		dev_err(dsi->dev, "cannot enable regulators %d\n", ret);
-		return ret;
-	}
-
-	for (i = 0; i < driver_data->num_clks; i++) {
-		ret = clk_prepare_enable(dsi->clks[i]);
-		if (ret < 0)
-			goto err_clk;
-	}
-
-	ret = phy_power_on(dsi->phy);
-	if (ret < 0) {
-		dev_err(dsi->dev, "cannot enable phy %d\n", ret);
-		goto err_clk;
-	}
-
-	return 0;
-
-err_clk:
-	while (--i > -1)
-		clk_disable_unprepare(dsi->clks[i]);
-	regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
-
-	return ret;
-}
-
-static void exynos_dsi_poweroff(struct exynos_dsi *dsi)
-{
-	struct exynos_dsi_driver_data *driver_data = dsi->driver_data;
-	int ret, i;
-
-	usleep_range(10000, 20000);
-
-	if (dsi->state & DSIM_STATE_INITIALIZED) {
-		dsi->state &= ~DSIM_STATE_INITIALIZED;
-
-		exynos_dsi_disable_clock(dsi);
-
-		exynos_dsi_disable_irq(dsi);
-	}
-
-	dsi->state &= ~DSIM_STATE_CMD_LPM;
-
-	phy_power_off(dsi->phy);
-
-	for (i = driver_data->num_clks - 1; i > -1; i--)
-		clk_disable_unprepare(dsi->clks[i]);
-
-	ret = regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
-	if (ret < 0)
-		dev_err(dsi->dev, "cannot disable regulators %d\n", ret);
-}
-
 static void exynos_dsi_enable(struct drm_encoder *encoder)
 {
 	struct exynos_dsi *dsi = encoder_to_dsi(encoder);
@@ -1526,16 +1466,14 @@ static void exynos_dsi_enable(struct drm_encoder *encoder)
 	if (dsi->state & DSIM_STATE_ENABLED)
 		return;
 
-	ret = exynos_dsi_poweron(dsi);
-	if (ret < 0)
-		return;
+	pm_runtime_get_sync(dsi->dev);
 
 	dsi->state |= DSIM_STATE_ENABLED;
 
 	ret = drm_panel_prepare(dsi->panel);
 	if (ret < 0) {
 		dsi->state &= ~DSIM_STATE_ENABLED;
-		exynos_dsi_poweroff(dsi);
+		pm_runtime_put_sync(dsi->dev);
 		return;
 	}
 
@@ -1547,7 +1485,7 @@ static void exynos_dsi_enable(struct drm_encoder *encoder)
 		dsi->state &= ~DSIM_STATE_ENABLED;
 		exynos_dsi_set_display_enable(dsi, false);
 		drm_panel_unprepare(dsi->panel);
-		exynos_dsi_poweroff(dsi);
+		pm_runtime_put_sync(dsi->dev);
 		return;
 	}
 
@@ -1569,7 +1507,7 @@ static void exynos_dsi_disable(struct drm_encoder *encoder)
 
 	dsi->state &= ~DSIM_STATE_ENABLED;
 
-	exynos_dsi_poweroff(dsi);
+	pm_runtime_put_sync(dsi->dev);
 }
 
 static enum drm_connector_status
@@ -1954,22 +1892,99 @@ static int exynos_dsi_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, &dsi->encoder);
 
+	pm_runtime_enable(dev);
+
 	return component_add(dev, &exynos_dsi_component_ops);
 }
 
 static int exynos_dsi_remove(struct platform_device *pdev)
 {
+	pm_runtime_disable(&pdev->dev);
+
 	component_del(&pdev->dev, &exynos_dsi_component_ops);
 
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int exynos_dsi_suspend(struct device *dev)
+{
+	struct drm_encoder *encoder = dev_get_drvdata(dev);
+	struct exynos_dsi *dsi = encoder_to_dsi(encoder);
+	struct exynos_dsi_driver_data *driver_data = dsi->driver_data;
+	int ret, i;
+
+	usleep_range(10000, 20000);
+
+	if (dsi->state & DSIM_STATE_INITIALIZED) {
+		dsi->state &= ~DSIM_STATE_INITIALIZED;
+
+		exynos_dsi_disable_clock(dsi);
+
+		exynos_dsi_disable_irq(dsi);
+	}
+
+	dsi->state &= ~DSIM_STATE_CMD_LPM;
+
+	phy_power_off(dsi->phy);
+
+	for (i = driver_data->num_clks - 1; i > -1; i--)
+		clk_disable_unprepare(dsi->clks[i]);
+
+	ret = regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
+	if (ret < 0)
+		dev_err(dsi->dev, "cannot disable regulators %d\n", ret);
+
+	return 0;
+}
+
+static int exynos_dsi_resume(struct device *dev)
+{
+	struct drm_encoder *encoder = dev_get_drvdata(dev);
+	struct exynos_dsi *dsi = encoder_to_dsi(encoder);
+	struct exynos_dsi_driver_data *driver_data = dsi->driver_data;
+	int ret, i;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
+	if (ret < 0) {
+		dev_err(dsi->dev, "cannot enable regulators %d\n", ret);
+		return ret;
+	}
+
+	for (i = 0; i < driver_data->num_clks; i++) {
+		ret = clk_prepare_enable(dsi->clks[i]);
+		if (ret < 0)
+			goto err_clk;
+	}
+
+	ret = phy_power_on(dsi->phy);
+	if (ret < 0) {
+		dev_err(dsi->dev, "cannot enable phy %d\n", ret);
+		goto err_clk;
+	}
+
+	return 0;
+
+err_clk:
+	while (--i > -1)
+		clk_disable_unprepare(dsi->clks[i]);
+	regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
+
+	return ret;
+}
+#endif
+
+static const struct dev_pm_ops exynos_dsi_pm_ops = {
+	SET_RUNTIME_PM_OPS(exynos_dsi_suspend, exynos_dsi_resume, NULL)
+};
+
 struct platform_driver dsi_driver = {
 	.probe = exynos_dsi_probe,
 	.remove = exynos_dsi_remove,
 	.driver = {
 		   .name = "exynos-dsi",
 		   .owner = THIS_MODULE,
+		   .pm = &exynos_dsi_pm_ops,
 		   .of_match_table = exynos_dsi_of_match,
 	},
 };