Merge tag 'drm/tegra/for-4.8-rc4' of git://anongit.freedesktop.org/tegra/linux into drm-fixes

drm/tegra: Fixes for v4.8-rc4

This contains one fix for DSI runtime power management support that was
introduced in v4.8-rc1. This is slightly more elaborate than I would've
wished, but there are a few corner cases that needed fixing.

* tag 'drm/tegra/for-4.8-rc4' of git://anongit.freedesktop.org/tegra/linux:
  drm/tegra: dsi: Enhance runtime power management

2 files changed, 67 insertions, 39 deletions

diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
index 3d228ad90e0f..3dea1216bafd 100644
--- a/drivers/gpu/drm/tegra/dsi.c
+++ b/drivers/gpu/drm/tegra/dsi.c
@@ -840,6 +840,21 @@ static const struct drm_encoder_funcs tegra_dsi_encoder_funcs = {
 	.destroy = tegra_output_encoder_destroy,
 };
 
+static void tegra_dsi_unprepare(struct tegra_dsi *dsi)
+{
+	int err;
+
+	if (dsi->slave)
+		tegra_dsi_unprepare(dsi->slave);
+
+	err = tegra_mipi_disable(dsi->mipi);
+	if (err < 0)
+		dev_err(dsi->dev, "failed to disable MIPI calibration: %d\n",
+			err);
+
+	pm_runtime_put(dsi->dev);
+}
+
 static void tegra_dsi_encoder_disable(struct drm_encoder *encoder)
 {
 	struct tegra_output *output = encoder_to_output(encoder);
@@ -876,7 +891,26 @@ static void tegra_dsi_encoder_disable(struct drm_encoder *encoder)
 
 	tegra_dsi_disable(dsi);
 
-	pm_runtime_put(dsi->dev);
+	tegra_dsi_unprepare(dsi);
+}
+
+static void tegra_dsi_prepare(struct tegra_dsi *dsi)
+{
+	int err;
+
+	pm_runtime_get_sync(dsi->dev);
+
+	err = tegra_mipi_enable(dsi->mipi);
+	if (err < 0)
+		dev_err(dsi->dev, "failed to enable MIPI calibration: %d\n",
+			err);
+
+	err = tegra_dsi_pad_calibrate(dsi);
+	if (err < 0)
+		dev_err(dsi->dev, "MIPI calibration failed: %d\n", err);
+
+	if (dsi->slave)
+		tegra_dsi_prepare(dsi->slave);
 }
 
 static void tegra_dsi_encoder_enable(struct drm_encoder *encoder)
@@ -887,13 +921,8 @@ static void tegra_dsi_encoder_enable(struct drm_encoder *encoder)
 	struct tegra_dsi *dsi = to_dsi(output);
 	struct tegra_dsi_state *state;
 	u32 value;
-	int err;
-
-	pm_runtime_get_sync(dsi->dev);
 
-	err = tegra_dsi_pad_calibrate(dsi);
-	if (err < 0)
-		dev_err(dsi->dev, "MIPI calibration failed: %d\n", err);
+	tegra_dsi_prepare(dsi);
 
 	state = tegra_dsi_get_state(dsi);
 
diff --git a/drivers/gpu/host1x/mipi.c b/drivers/gpu/host1x/mipi.c
index 52a6fd224127..e00809d996a2 100644
--- a/drivers/gpu/host1x/mipi.c
+++ b/drivers/gpu/host1x/mipi.c
@@ -242,20 +242,6 @@ struct tegra_mipi_device *tegra_mipi_request(struct device *device)
 	dev->pads = args.args[0];
 	dev->device = device;
 
-	mutex_lock(&dev->mipi->lock);
-
-	if (dev->mipi->usage_count++ == 0) {
-		err = tegra_mipi_power_up(dev->mipi);
-		if (err < 0) {
-			dev_err(dev->mipi->dev,
-				"failed to power up MIPI bricks: %d\n",
-				err);
-			return ERR_PTR(err);
-		}
-	}
-
-	mutex_unlock(&dev->mipi->lock);
-
 	return dev;
 
 put:
@@ -270,29 +256,42 @@ EXPORT_SYMBOL(tegra_mipi_request);
 
 void tegra_mipi_free(struct tegra_mipi_device *device)
 {
-	int err;
+	platform_device_put(device->pdev);
+	kfree(device);
+}
+EXPORT_SYMBOL(tegra_mipi_free);
 
-	mutex_lock(&device->mipi->lock);
+int tegra_mipi_enable(struct tegra_mipi_device *dev)
+{
+	int err = 0;
 
-	if (--device->mipi->usage_count == 0) {
-		err = tegra_mipi_power_down(device->mipi);
-		if (err < 0) {
-			/*
-			 * Not much that can be done here, so an error message
-			 * will have to do.
-			 */
-			dev_err(device->mipi->dev,
-				"failed to power down MIPI bricks: %d\n",
-				err);
-		}
-	}
+	mutex_lock(&dev->mipi->lock);
 
-	mutex_unlock(&device->mipi->lock);
+	if (dev->mipi->usage_count++ == 0)
+		err = tegra_mipi_power_up(dev->mipi);
+
+	mutex_unlock(&dev->mipi->lock);
+
+	return err;
 
-	platform_device_put(device->pdev);
-	kfree(device);
 }
-EXPORT_SYMBOL(tegra_mipi_free);
+EXPORT_SYMBOL(tegra_mipi_enable);
+
+int tegra_mipi_disable(struct tegra_mipi_device *dev)
+{
+	int err = 0;
+
+	mutex_lock(&dev->mipi->lock);
+
+	if (--dev->mipi->usage_count == 0)
+		err = tegra_mipi_power_down(dev->mipi);
+
+	mutex_unlock(&dev->mipi->lock);
+
+	return err;
+
+}
+EXPORT_SYMBOL(tegra_mipi_disable);
 
 static int tegra_mipi_wait(struct tegra_mipi *mipi)
 {