From: Willy Wolff <willy.mh.wolff.ml@gmail.com>
Date: Sat, 21 Mar 2020 09:27:40 +0000
Subject: thermal/drivers/cpufreq_cooling: Fix return of cpufreq_set_cur_state

Git-commit: ff44f672d74178b3be19d41a169b98b3e391d4ce
Patch-mainline: v5.7-rc1
References: bsc#1168476

When setting the cooling device current state from userspace via sysfs,
the operation fails by returning an -EINVAL.

It appears the recent changes with the per-policy frequency QoS
introduced a regression as reported by:

 https://lkml.org/lkml/2020/3/20/599

The function freq_qos_update_request returns 0 or 1 describing update
effectiveness, and a negative error code on failure. However,
cpufreq_set_cur_state returns 0 on success or an error code otherwise.

Consider the QoS update as successful if the function does not return
an error.

Fixes: 3000ce3c52f8b ("cpufreq: Use per-policy frequency QoS")
Signed-off-by: Willy Wolff <willy.mh.wolff.ml@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200321092740.7vvwfxsebcrznydh@macmini.local
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
 drivers/thermal/cpu_cooling.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -320,6 +320,7 @@ static int cpufreq_set_cur_state(struct
 				 unsigned long state)
 {
 	struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata;
+	int ret;
 
 	/* Request state should be less than max_level */
 	if (WARN_ON(state > cpufreq_cdev->max_level))
@@ -331,8 +332,9 @@ static int cpufreq_set_cur_state(struct
 
 	cpufreq_cdev->cpufreq_state = state;
 
-	return freq_qos_update_request(&cpufreq_cdev->qos_req,
+	ret = freq_qos_update_request(&cpufreq_cdev->qos_req,
 				cpufreq_cdev->freq_table[state].frequency);
+	return ret < 0 ? ret : 0;
 }
 
 /**