The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 2a9a86d5c81389cd9afe6a4fea42c585733cd705 Mon Sep 17 00:00:00 2001
From: Tero Kristo <t-kristo@xxxxxx>
Date: Mon, 30 Oct 2017 09:10:46 +0200
Subject: [PATCH] PM / QoS: Fix default runtime_pm device resume latency
The recent change to the PM QoS framework to introduce a proper
no constraint value overlooked to handle the devices which don't
implement PM QoS OPS. Runtime PM is one of the more severely
impacted subsystems, failing every attempt to runtime suspend
a device. This leads into some nasty second level issues like
probe failures and increased power consumption among other
things.
Fix this by adding a proper return value for devices that don't
implement PM QoS.
Fixes: 0cc2b4e5a020 (PM / QoS: Fix device resume latency PM QoS)
Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
Cc: All applicable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
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,