Merge tag 'devfreq-fixes-for-5.5-rc2' of...

Merge tag 'devfreq-fixes-for-5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux

Pull devfreq updates for 5.5-rc1 from Chanwoo Choi:

"Update devfreq core:

 - Add PM QoS support for devfreq device with following QoS type.
   External user of devfreq device can request the minimum and
   maximum frequency according to their multiple requirements.
   : DEV_PM_QOS_MIN_FREQUENCY is used for requesting the minimum
     device frequency.
   : DEV_PM_QOS_MAX_FREQUENCY is used for requesting the maximum
     device frequency.

 - Use PM QoS interface when entering the min/max_freq via sysfs
   interface.

 - Add get_freq_range() helper function in order to get the final
   min/max frequency among the multiple requirements of min/max
   frequency.

 - Fix a function return value and modify code for more correct
   exception handling if errors happen."

* tag 'devfreq-fixes-for-5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux:
  PM / devfreq: Use PM QoS for sysfs min/max_freq
  PM / devfreq: Add PM QoS support
  PM / devfreq: Don't fail devfreq_dev_release if not in list
  PM / devfreq: Introduce get_freq_range helper
  PM / devfreq: Set scaling_max_freq to max on OPP notifier error
  PM / devfreq: Fix devfreq_notifier_call returning errno

include/linux/devfreq.h

@@ -13,6 +13,7 @@
 #include <linux/device.h>
 #include <linux/notifier.h>
 #include <linux/pm_opp.h>
+#include <linux/pm_qos.h>
 
 #define DEVFREQ_NAME_LEN 16
 
@@ -123,8 +124,8 @@ struct devfreq_dev_profile {
  * @previous_freq:	previously configured frequency value.
  * @data:	Private data of the governor. The devfreq framework does not
  *		touch this.
- * @min_freq:	Limit minimum frequency requested by user (0: none)
- * @max_freq:	Limit maximum frequency requested by user (0: none)
+ * @user_min_freq_req:	PM QoS minimum frequency request from user (via sysfs)
+ * @user_max_freq_req:	PM QoS maximum frequency request from user (via sysfs)
  * @scaling_min_freq:	Limit minimum frequency requested by OPP interface
  * @scaling_max_freq:	Limit maximum frequency requested by OPP interface
  * @stop_polling:	 devfreq polling status of a device.
@@ -136,6 +137,8 @@ struct devfreq_dev_profile {
  * @time_in_state:	Statistics of devfreq states
  * @last_stat_updated:	The last time stat updated
  * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
+ * @nb_min:		Notifier block for DEV_PM_QOS_MIN_FREQUENCY
+ * @nb_max:		Notifier block for DEV_PM_QOS_MAX_FREQUENCY
  *
  * This structure stores the devfreq information for a give device.
  *
@@ -161,8 +164,8 @@ struct devfreq {
 
 	void *data; /* private data for governors */
 
-	unsigned long min_freq;
-	unsigned long max_freq;
+	struct dev_pm_qos_request user_min_freq_req;
+	struct dev_pm_qos_request user_max_freq_req;
 	unsigned long scaling_min_freq;
 	unsigned long scaling_max_freq;
 	bool stop_polling;
@@ -178,6 +181,9 @@ struct devfreq {
 	unsigned long last_stat_updated;
 
 	struct srcu_notifier_head transition_notifier_list;
+
+	struct notifier_block nb_min;
+	struct notifier_block nb_max;
 };
 
 struct devfreq_freqs {