[1/2] drm: atmel-hlcdc: Add PM suspend/resume support

Commit Message

Sylvain Rochet Feb. 10, 2015, 1:40 p.m. UTC

On suspend: switch off CRTC if not already suspended with runtime PM

On resume: switch on CRTC if we were not already suspended from runtime
PM while suspending.

Signed-off-by: Sylvain Rochet <[e-mail]>
---
 drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c | 60 ++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

Comments

Sylvain Rochet Feb. 10, 2015, 2:43 p.m. UTC | #1

Hello Boris,

On Tue, Feb 10, 2015 at 03:05:57PM +0100, Boris Brezillon wrote:
> On Tue, 10 Feb 2015 14:40:45 +0100
> Sylvain Rochet <[e-mail]> wrote:
> > +
> > +static SIMPLE_DEV_PM_OPS(atmel_hlcdc_dc_drm_pm_ops,
> > +		atmel_hlcdc_dc_drm_suspend, atmel_hlcdc_dc_drm_resume);
> > +
> 
> Do we really need to register both SIMPLE_DEV_PM_OPS and drm_driver
> suspend/resume functions.
> I thought the suspend/resume callbacks were called by DRM core code
> as part of the PM class specific operations.
> However, exynos driver seems to do the same, so this might well be
> required.

Looks like we need, if I comment out SIMPLE_DEV_PM_OPS ops registration 
we don't suspend or resume anymore. I guess drm_driver suspend/resume 
functions are only used for PM runtime support, which we don't support 
yet, at least we added the basic requirements to add PM runtime support 
at some point in the future.

Anyway, even without PM runtime support we need to suspend and resume 
this device, other DRM drivers do this as well.

Sylvain

Patch

diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
index 22c3cca..4c89bd2 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
@@ -427,6 +427,36 @@  static void atmel_hlcdc_dc_lastclose(struct drm_device *dev)
 	drm_fbdev_cma_restore_mode(dc->fbdev);
 }
 
+static int atmel_hlcdc_dc_suspend(struct drm_device *dev, pm_message_t state)
+{
+	struct drm_crtc *crtc;
+
+	drm_modeset_lock_all(dev);
+
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+		struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
+		(*crtc_funcs->disable)(crtc);
+	}
+
+	drm_modeset_unlock_all(dev);
+	return 0;
+}
+
+static int atmel_hlcdc_dc_resume(struct drm_device *dev)
+{
+	struct drm_crtc *crtc;
+
+	drm_modeset_lock_all(dev);
+
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+		struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
+		(*crtc_funcs->enable)(crtc);
+	}
+
+	drm_modeset_unlock_all(dev);
+	return 0;
+}
+
 static int atmel_hlcdc_dc_irq_postinstall(struct drm_device *dev)
 {
 	struct atmel_hlcdc_dc *dc = dev->dev_private;
@@ -488,6 +518,8 @@  static struct drm_driver atmel_hlcdc_dc_driver = {
 	.driver_features = DRIVER_HAVE_IRQ | DRIVER_GEM | DRIVER_MODESET,
 	.preclose = atmel_hlcdc_dc_preclose,
 	.lastclose = atmel_hlcdc_dc_lastclose,
+	.suspend = atmel_hlcdc_dc_suspend,
+	.resume = atmel_hlcdc_dc_resume,
 	.irq_handler = atmel_hlcdc_dc_irq_handler,
 	.irq_preinstall = atmel_hlcdc_dc_irq_uninstall,
 	.irq_postinstall = atmel_hlcdc_dc_irq_postinstall,
@@ -559,6 +591,33 @@  static int atmel_hlcdc_dc_drm_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int atmel_hlcdc_dc_drm_suspend(struct device *dev)
+{
+	struct drm_device *drm_dev = dev_get_drvdata(dev);
+	pm_message_t message;
+
+	if (pm_runtime_suspended(dev) || !drm_dev)
+		return 0;
+
+	message.event = PM_EVENT_SUSPEND;
+	return atmel_hlcdc_dc_suspend(drm_dev, message);
+}
+
+static int atmel_hlcdc_dc_drm_resume(struct device *dev)
+{
+	struct drm_device *drm_dev = dev_get_drvdata(dev);
+
+	if (pm_runtime_suspended(dev) || !drm_dev)
+		return 0;
+
+	return atmel_hlcdc_dc_resume(drm_dev);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(atmel_hlcdc_dc_drm_pm_ops,
+		atmel_hlcdc_dc_drm_suspend, atmel_hlcdc_dc_drm_resume);
+
 static const struct of_device_id atmel_hlcdc_dc_of_match[] = {
 	{ .compatible = "atmel,hlcdc-display-controller" },
 	{ },
@@ -569,6 +628,7 @@  static struct platform_driver atmel_hlcdc_dc_platform_driver = {
 	.remove	= atmel_hlcdc_dc_drm_remove,
 	.driver	= {
 		.name	= "atmel-hlcdc-display-controller",
+		.pm	= &atmel_hlcdc_dc_drm_pm_ops,
 		.of_match_table = atmel_hlcdc_dc_of_match,
 	},
 };