[PATCH] drm/tegra: dsi: Add suspend/resume support

From: Mark Zhang
Date: Mon Dec 08 2014 - 01:41:26 EST


This patch adds the suspend/resume support for Tegra drm
driver by calling the corresponding DPMS functions.

Signed-off-by: Mark Zhang <markz@xxxxxxxxxx>
---
Hi,

This patch hooks DSI driver's suspend/resume to implement the whole
display system's suspend/resume. I know this is a super ugly way,
but as we all know, Tegra DRM driver doesn't have a dedicate drm device
so honestly I didn't find a better way to do that.

Thanks,
Mark

drivers/gpu/drm/tegra/dsi.c | 96 ++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 90 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
index 33f67fd601c6..25cd0d93f392 100644
--- a/drivers/gpu/drm/tegra/dsi.c
+++ b/drivers/gpu/drm/tegra/dsi.c
@@ -61,6 +61,9 @@ struct tegra_dsi {
struct tegra_dsi *slave;
};

+static int tegra_dsi_pad_calibrate(struct tegra_dsi *);
+static int tegra_dsi_ganged_setup(struct tegra_dsi *dsi);
+
static inline struct tegra_dsi *
host1x_client_to_dsi(struct host1x_client *client)
{
@@ -805,6 +808,20 @@ static int tegra_output_dsi_setup_clock(struct tegra_output *output,

lanes = tegra_dsi_get_lanes(dsi);

+ err = tegra_dsi_pad_calibrate(dsi);
+ if (err < 0) {
+ dev_err(dsi->dev, "MIPI calibration failed: %d\n", err);
+ return err;
+ }
+ if (dsi->slave) {
+ err = tegra_dsi_pad_calibrate(dsi->slave);
+ if (err < 0) {
+ dev_err(dsi->slave->dev,
+ "MIPI calibration failed: %d\n", err);
+ return err;
+ }
+ }
+
err = tegra_dsi_get_muldiv(dsi->format, &mul, &div);
if (err < 0)
return err;
@@ -833,6 +850,13 @@ static int tegra_output_dsi_setup_clock(struct tegra_output *output,
dev_err(dsi->dev, "failed to set parent clock: %d\n", err);
return err;
}
+ if (dsi->slave) {
+ err = tegra_dsi_ganged_setup(dsi);
+ if (err < 0) {
+ dev_err(dsi->dev, "DSI ganged setup failed: %d\n", err);
+ return err;
+ }
+ }

err = clk_set_rate(dsi->clk_parent, plld);
if (err < 0) {
@@ -1470,12 +1494,6 @@ static int tegra_dsi_probe(struct platform_device *pdev)
goto disable_vdd;
}

- err = tegra_dsi_pad_calibrate(dsi);
- if (err < 0) {
- dev_err(dsi->dev, "MIPI calibration failed: %d\n", err);
- goto mipi_free;
- }
-
dsi->host.ops = &tegra_dsi_host_ops;
dsi->host.dev = &pdev->dev;

@@ -1544,6 +1562,67 @@ static int tegra_dsi_remove(struct platform_device *pdev)
return 0;
}

+#ifdef CONFIG_PM
+static int tegra_dsi_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct tegra_dsi *dsi = platform_get_drvdata(pdev);
+ struct tegra_drm *tegra = dev_get_drvdata(dsi->client.parent);
+ struct drm_connector *connector;
+
+ if (dsi->master) {
+ regulator_disable(dsi->vdd);
+ return 0;
+ }
+
+ drm_modeset_lock_all(tegra->drm);
+ list_for_each_entry(connector, &tegra->drm->mode_config.connector_list,
+ head) {
+ int old_dpms = connector->dpms;
+
+ if (connector->funcs->dpms)
+ connector->funcs->dpms(connector, DRM_MODE_DPMS_OFF);
+
+ /* Set the old mode back to the connector for resume */
+ connector->dpms = old_dpms;
+ }
+ drm_modeset_unlock_all(tegra->drm);
+
+ regulator_disable(dsi->vdd);
+
+ return 0;
+}
+
+static int tegra_dsi_resume(struct platform_device *pdev)
+{
+ struct tegra_dsi *dsi = platform_get_drvdata(pdev);
+ struct tegra_drm *tegra = dev_get_drvdata(dsi->client.parent);
+ struct drm_connector *connector;
+ int err = 0;
+
+ err = regulator_enable(dsi->vdd);
+ if (err < 0) {
+ dev_err(&pdev->dev, "Enable DSI vdd failed: %d\n", err);
+ return err;
+ }
+
+ if (dsi->master)
+ return 0;
+
+ drm_modeset_lock_all(tegra->drm);
+ list_for_each_entry(connector, &tegra->drm->mode_config.connector_list,
+ head) {
+ if (connector->funcs->dpms)
+ connector->funcs->dpms(connector, connector->dpms);
+ }
+ drm_modeset_unlock_all(tegra->drm);
+
+ drm_helper_resume_force_mode(tegra->drm);
+
+ return 0;
+}
+#endif
+
+
static const struct of_device_id tegra_dsi_of_match[] = {
{ .compatible = "nvidia,tegra114-dsi", },
{ },
@@ -1557,4 +1636,9 @@ struct platform_driver tegra_dsi_driver = {
},
.probe = tegra_dsi_probe,
.remove = tegra_dsi_remove,
+#ifdef CONFIG_PM
+ .suspend = tegra_dsi_suspend,
+ .resume = tegra_dsi_resume,
+#endif
+
};
--
1.8.1.5

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