On Wed, Jun 08, 2016 at 12:49:29PM +0200, Lukas Wunner wrote:
The PM core introduced the ability to keep devices runtime suspended during the entire system suspend/resume process with commit aae4518b3124 ("PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily"). Before this so-called "direct-complete" procedure was introduced, devices were always runtime resumed only to be immediately put to sleep again using their ->suspend hook. Direct-complete is enabled by returning a positive value from the ->prepare hook. The PCI core usually does this automatically.
Direct-complete is only available for a device if all children use it as well. Currently we cannot support direct-complete for DRM drivers because the DRM core automatically registers multiple DRM minors which belong to device class drm_class, and drm_class uses a struct dev_pm_ops which lacks the ->prepare callback.
While this could be solved by adding the missing ->prepare callback, closer inspection shows that there are no DRM drivers left which declare the legacy ->suspend and ->resume callbacks in their drm_driver struct. The last ones to remove them were i915 with commit 1751fcf9f92e ("drm/i915: Fix module initialisation, v2.") and exynos with commit e7fefb1d5af5 ("drm/exynos: remove legacy ->suspend()/resume()").
Consequently the struct dev_pm_ops of drm_class is now dead code. Remove it. If no dev_pm_ops is declared for a device, the PM core automatically enables direct-complete for it, thereby making that mechanism available to the parent DRM PCI devices.
Signed-off-by: Lukas Wunner lukas@wunner.de
wow, awesome!
/me pops some champange
This is excellent really. Applied to drm-misc, but I'll wait with pushing out since I want to roll forward to the latest drm-next that Dave promised to push out tomorrow. -Daniel
drivers/gpu/drm/drm_drv.c | 2 -- drivers/gpu/drm/drm_sysfs.c | 71 --------------------------------------------- include/drm/drmP.h | 2 -- 3 files changed, 75 deletions(-)
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index bff8922..8b2582a 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -605,8 +605,6 @@ struct drm_device *drm_dev_alloc(struct drm_driver *driver, ret = drm_minor_alloc(dev, DRM_MINOR_CONTROL); if (ret) goto err_minors;
WARN_ON(driver->suspend || driver->resume);}
if (drm_core_check_feature(dev, DRIVER_RENDER)) {
diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c index fa7fadc..32dd821 100644 --- a/drivers/gpu/drm/drm_sysfs.c +++ b/drivers/gpu/drm/drm_sysfs.c @@ -32,75 +32,6 @@ static struct device_type drm_sysfs_device_minor = {
struct class *drm_class;
-/**
- __drm_class_suspend - internal DRM class suspend routine
- @dev: Linux device to suspend
- @state: power state to enter
- Just figures out what the actual struct drm_device associated with
- @dev is and calls its suspend hook, if present.
- */
-static int __drm_class_suspend(struct device *dev, pm_message_t state) -{
- if (dev->type == &drm_sysfs_device_minor) {
struct drm_minor *drm_minor = to_drm_minor(dev);struct drm_device *drm_dev = drm_minor->dev;if (drm_minor->type == DRM_MINOR_LEGACY &&!drm_core_check_feature(drm_dev, DRIVER_MODESET) &&drm_dev->driver->suspend)return drm_dev->driver->suspend(drm_dev, state);- }
- return 0;
-}
-/**
- drm_class_suspend - internal DRM class suspend hook. Simply calls
- __drm_class_suspend() with the correct pm state.
- @dev: Linux device to suspend
- */
-static int drm_class_suspend(struct device *dev) -{
- return __drm_class_suspend(dev, PMSG_SUSPEND);
-}
-/**
- drm_class_freeze - internal DRM class freeze hook. Simply calls
- __drm_class_suspend() with the correct pm state.
- @dev: Linux device to freeze
- */
-static int drm_class_freeze(struct device *dev) -{
- return __drm_class_suspend(dev, PMSG_FREEZE);
-}
-/**
- drm_class_resume - DRM class resume hook
- @dev: Linux device to resume
- Just figures out what the actual struct drm_device associated with
- @dev is and calls its resume hook, if present.
- */
-static int drm_class_resume(struct device *dev) -{
- if (dev->type == &drm_sysfs_device_minor) {
struct drm_minor *drm_minor = to_drm_minor(dev);struct drm_device *drm_dev = drm_minor->dev;if (drm_minor->type == DRM_MINOR_LEGACY &&!drm_core_check_feature(drm_dev, DRIVER_MODESET) &&drm_dev->driver->resume)return drm_dev->driver->resume(drm_dev);- }
- return 0;
-}
-static const struct dev_pm_ops drm_class_dev_pm_ops = {
- .suspend = drm_class_suspend,
- .resume = drm_class_resume,
- .freeze = drm_class_freeze,
-};
static char *drm_devnode(struct device *dev, umode_t *mode) { return kasprintf(GFP_KERNEL, "dri/%s", dev_name(dev)); @@ -131,8 +62,6 @@ int drm_sysfs_init(void) if (IS_ERR(drm_class)) return PTR_ERR(drm_class);
- drm_class->pm = &drm_class_dev_pm_ops;
- err = class_create_file(drm_class, &class_attr_version.attr); if (err) { class_destroy(drm_class);
diff --git a/include/drm/drmP.h b/include/drm/drmP.h index c5d2950..fc40543 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -416,8 +416,6 @@ struct drm_driver { void (*postclose) (struct drm_device *, struct drm_file *); void (*lastclose) (struct drm_device *); int (*unload) (struct drm_device *);
- int (*suspend) (struct drm_device *, pm_message_t state);
- int (*resume) (struct drm_device *); int (*dma_ioctl) (struct drm_device *dev, void *data, struct drm_file *file_priv); int (*dma_quiescent) (struct drm_device *); int (*context_dtor) (struct drm_device *dev, int context);
-- 2.8.1
dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel