[PATCH 03/10] PM / QoS: Fix device resume latency for non PM QoS devices

[Manikanta Maddireddy <mmaddireddy-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>]

In 'commit 0cc2b4e5a020 ("PM / QoS: Fix device resume latency PM QoS")'
PM QoS resume latency modified 0 as "no latency at all". However
dev_pm_qos_raw_read_value() returns 0 for devices which doesn't have
PM QoS constraints. This is blocking runtime suspend for these devices
in rpm_check_suspend_allowed(). Return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT
when PM QoS constraints are not available for a particular device.

Fixes: 0cc2b4e5a020 ("PM / QoS: Fix device resume latency PM QoS")
Signed-off-by: Manikanta Maddireddy <mmaddireddy-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
 include/linux/pm_qos.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 6737a8c9e8c6..d68b0569a5eb 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -175,7 +175,8 @@ static inline s32 dev_pm_qos_requested_flags(struct device *dev)
 static inline s32 dev_pm_qos_raw_read_value(struct device *dev)
 {
 	return IS_ERR_OR_NULL(dev->power.qos) ?
-		0 : pm_qos_read_value(&dev->power.qos->resume_latency);
+		PM_QOS_RESUME_LATENCY_NO_CONSTRAINT :
+		pm_qos_read_value(&dev->power.qos->resume_latency);
 }
 #else
 static inline enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev,
-- 
2.1.4