[PATCH] PM: core: Fix device_pm_check_callbacks()

From: Rafael J. Wysocki
Date: Mon Sep 18 2017 - 20:31:47 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

The device_pm_check_callbacks() function doesn't check legacy
->suspend and ->resume callback pointers under the device's
bus type, class and driver, so in some cases it may set the
no_pm_callbacks flag for the device incorrectly and then the
callbacks may be skipped during system suspend/resume, which
shouldn't happen.

Fixes: aa8e54b55947 (PM / sleep: Go direct_complete if driver has no callbacks)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/base/power/main.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

Index: linux-pm/drivers/base/power/main.c
===================================================================
--- linux-pm.orig/drivers/base/power/main.c
+++ linux-pm/drivers/base/power/main.c
@@ -1860,10 +1860,13 @@ void device_pm_check_callbacks(struct de
{
spin_lock_irq(&dev->power.lock);
dev->power.no_pm_callbacks =
- (!dev->bus || pm_ops_is_empty(dev->bus->pm)) &&
- (!dev->class || pm_ops_is_empty(dev->class->pm)) &&
+ (!dev->bus || (pm_ops_is_empty(dev->bus->pm) &&
+ !dev->bus->suspend && !dev->bus->resume)) &&
+ (!dev->class || (pm_ops_is_empty(dev->class->pm) &&
+ !dev->class->suspend && !dev->class->resume)) &&
(!dev->type || pm_ops_is_empty(dev->type->pm)) &&
(!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) &&
- (!dev->driver || pm_ops_is_empty(dev->driver->pm));
+ (!dev->driver || (pm_ops_is_empty(dev->driver->pm) &&
+ !dev->driver->suspend && !dev->driver->resume));
spin_unlock_irq(&dev->power.lock);
}