1 files changed, 86 insertions, 6 deletions

diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c b/drivers/gpu/drm/rcar-du/rcar_lvds.c
index 81a060c2fe3f..260ea5d8624e 100644
--- a/drivers/gpu/drm/rcar-du/rcar_lvds.c
+++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c
@@ -16,6 +16,8 @@
 #include <linux/of_device.h>
 #include <linux/of_graph.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
 #include <linux/slab.h>
 #include <linux/sys_soc.h>
 
@@ -60,6 +62,7 @@ struct rcar_lvds_device_info {
 struct rcar_lvds {
 	struct device *dev;
 	const struct rcar_lvds_device_info *info;
+	struct reset_control *rstc;
 
 	struct drm_bridge bridge;
 
@@ -80,6 +83,11 @@ struct rcar_lvds {
 #define bridge_to_rcar_lvds(b) \
 	container_of(b, struct rcar_lvds, bridge)
 
+static u32 rcar_lvds_read(struct rcar_lvds *lvds, u32 reg)
+{
+	return ioread32(lvds->mmio + reg);
+}
+
 static void rcar_lvds_write(struct rcar_lvds *lvds, u32 reg, u32 data)
 {
 	iowrite32(data, lvds->mmio + reg);
@@ -316,8 +324,8 @@ int rcar_lvds_pclk_enable(struct drm_bridge *bridge, unsigned long freq)
 
 	dev_dbg(lvds->dev, "enabling LVDS PLL, freq=%luHz\n", freq);
 
-	ret = clk_prepare_enable(lvds->clocks.mod);
-	if (ret < 0)
+	ret = pm_runtime_resume_and_get(lvds->dev);
+	if (ret)
 		return ret;
 
 	__rcar_lvds_pll_setup_d3_e3(lvds, freq, true);
@@ -337,7 +345,7 @@ void rcar_lvds_pclk_disable(struct drm_bridge *bridge)
 
 	rcar_lvds_write(lvds, LVDPLLCR, 0);
 
-	clk_disable_unprepare(lvds->clocks.mod);
+	pm_runtime_put_sync(lvds->dev);
 }
 EXPORT_SYMBOL_GPL(rcar_lvds_pclk_disable);
 
@@ -396,8 +404,8 @@ static void __rcar_lvds_atomic_enable(struct drm_bridge *bridge,
 	u32 lvdcr0;
 	int ret;
 
-	ret = clk_prepare_enable(lvds->clocks.mod);
-	if (ret < 0)
+	ret = pm_runtime_resume_and_get(lvds->dev);
+	if (ret)
 		return;
 
 	/* Enable the companion LVDS encoder in dual-link mode. */
@@ -541,6 +549,32 @@ static void rcar_lvds_atomic_disable(struct drm_bridge *bridge,
 				     struct drm_bridge_state *old_bridge_state)
 {
 	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
+	u32 lvdcr0;
+
+	/*
+	 * Clear the LVDCR0 bits in the order specified by the hardware
+	 * documentation, ending with a write of 0 to the full register to
+	 * clear all remaining bits.
+	 */
+	lvdcr0 = rcar_lvds_read(lvds, LVDCR0);
+
+	lvdcr0 &= ~LVDCR0_LVRES;
+	rcar_lvds_write(lvds, LVDCR0, lvdcr0);
+
+	if (lvds->info->quirks & RCAR_LVDS_QUIRK_GEN3_LVEN) {
+		lvdcr0 &= ~LVDCR0_LVEN;
+		rcar_lvds_write(lvds, LVDCR0, lvdcr0);
+	}
+
+	if (lvds->info->quirks & RCAR_LVDS_QUIRK_PWD) {
+		lvdcr0 &= ~LVDCR0_PWD;
+		rcar_lvds_write(lvds, LVDCR0, lvdcr0);
+	}
+
+	if (!(lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL)) {
+		lvdcr0 &= ~LVDCR0_PLLON;
+		rcar_lvds_write(lvds, LVDCR0, lvdcr0);
+	}
 
 	rcar_lvds_write(lvds, LVDCR0, 0);
 	rcar_lvds_write(lvds, LVDCR1, 0);
@@ -551,7 +585,7 @@ static void rcar_lvds_atomic_disable(struct drm_bridge *bridge,
 		lvds->companion->funcs->atomic_disable(lvds->companion,
 						       old_bridge_state);
 
-	clk_disable_unprepare(lvds->clocks.mod);
+	pm_runtime_put_sync(lvds->dev);
 }
 
 static bool rcar_lvds_mode_fixup(struct drm_bridge *bridge,
@@ -844,6 +878,13 @@ static int rcar_lvds_probe(struct platform_device *pdev)
 	if (ret < 0)
 		return ret;
 
+	lvds->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+	if (IS_ERR(lvds->rstc))
+		return dev_err_probe(&pdev->dev, PTR_ERR(lvds->rstc),
+				     "failed to get cpg reset\n");
+
+	pm_runtime_enable(&pdev->dev);
+
 	drm_bridge_add(&lvds->bridge);
 
 	return 0;
@@ -855,6 +896,8 @@ static int rcar_lvds_remove(struct platform_device *pdev)
 
 	drm_bridge_remove(&lvds->bridge);
 
+	pm_runtime_disable(&pdev->dev);
+
 	return 0;
 }
 
@@ -913,11 +956,48 @@ static const struct of_device_id rcar_lvds_of_table[] = {
 
 MODULE_DEVICE_TABLE(of, rcar_lvds_of_table);
 
+static int rcar_lvds_runtime_suspend(struct device *dev)
+{
+	struct rcar_lvds *lvds = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(lvds->clocks.mod);
+
+	reset_control_assert(lvds->rstc);
+
+	return 0;
+}
+
+static int rcar_lvds_runtime_resume(struct device *dev)
+{
+	struct rcar_lvds *lvds = dev_get_drvdata(dev);
+	int ret;
+
+	ret = reset_control_deassert(lvds->rstc);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(lvds->clocks.mod);
+	if (ret < 0)
+		goto err_reset_assert;
+
+	return 0;
+
+err_reset_assert:
+	reset_control_assert(lvds->rstc);
+
+	return ret;
+}
+
+static const struct dev_pm_ops rcar_lvds_pm_ops = {
+	SET_RUNTIME_PM_OPS(rcar_lvds_runtime_suspend, rcar_lvds_runtime_resume, NULL)
+};
+
 static struct platform_driver rcar_lvds_platform_driver = {
 	.probe		= rcar_lvds_probe,
 	.remove		= rcar_lvds_remove,
 	.driver		= {
 		.name	= "rcar-lvds",
+		.pm	= &rcar_lvds_pm_ops,
 		.of_match_table = rcar_lvds_of_table,
 	},
 };