QOS requests for DEFAULT_VALUE are supposed to be ignored but this is
not the case for FREQ_QOS_MAX. Adding one request for MAX_DEFAULT_VALUE
and one for a real value will cause freq_qos_read_value to unexpectedly
return MAX_DEFAULT_VALUE (-1).
This happens because freq_qos max value is aggregated with PM_QOS_MIN
but FREQ_QOS_MAX_DEFAULT_VALUE is (-1) so it's smaller than other
values.
Fix this by redefining FREQ_QOS_MAX_DEFAULT_VALUE to S32_MAX.
Looking at current users for freq_qos it seems that none of them create
requests for FREQ_QOS_MAX_DEFAULT_VALUE.
Fixes: 77751a466ebd ("PM: QoS: Introduce frequency QoS")
Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
Reported-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
---
include/linux/pm_qos.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index ebf5ef17cc2a..24a6263c9931 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -254,11 +254,11 @@ static inline s32 dev_pm_qos_raw_resume_latency(struct device *dev)
return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
}
#endif
#define FREQ_QOS_MIN_DEFAULT_VALUE 0
-#define FREQ_QOS_MAX_DEFAULT_VALUE (-1)
+#define FREQ_QOS_MAX_DEFAULT_VALUE S32_MAX
enum freq_qos_req_type {
FREQ_QOS_MIN = 1,
FREQ_QOS_MAX,
};
--
2.17.1
