@@ -482,10 +482,13 @@ static void devfreq_monitor(struct work_struct *work)
* to be called from governor in response to DEVFREQ_GOV_START
* event when device is added to devfreq framework.
*/
-void devfreq_monitor_start(struct devfreq *devfreq)
+int devfreq_monitor_start(struct devfreq *devfreq)
{
if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN))
- return;
+ return 0;
+
+ if (!devfreq->profile->get_dev_status)
+ return -EINVAL;
switch (devfreq->profile->timer) {
case DEVFREQ_TIMER_DEFERRABLE:
@@ -495,12 +498,13 @@ void devfreq_monitor_start(struct devfreq *devfreq)
INIT_DELAYED_WORK(&devfreq->work, devfreq_monitor);
break;
default:
- return;
+ return -EINVAL;
}
if (devfreq->profile->polling_ms)
queue_delayed_work(devfreq_wq, &devfreq->work,
msecs_to_jiffies(devfreq->profile->polling_ms));
+ return 0;
}
EXPORT_SYMBOL(devfreq_monitor_start);
@@ -75,7 +75,7 @@ struct devfreq_governor {
unsigned int event, void *data);
};
-void devfreq_monitor_start(struct devfreq *devfreq);
+int devfreq_monitor_start(struct devfreq *devfreq);
void devfreq_monitor_stop(struct devfreq *devfreq);
void devfreq_monitor_suspend(struct devfreq *devfreq);
void devfreq_monitor_resume(struct devfreq *devfreq);
@@ -89,8 +89,7 @@ static int devfreq_simple_ondemand_handler(struct devfreq *devfreq,
{
switch (event) {
case DEVFREQ_GOV_START:
- devfreq_monitor_start(devfreq);
- break;
+ return devfreq_monitor_start(devfreq);
case DEVFREQ_GOV_STOP:
devfreq_monitor_stop(devfreq);
The devfreq monitor depends on the device to provide load information by .get_dev_status() to calculate the next target freq. And this will cause changing governor to simple ondemand fail if device can't support. Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> --- drivers/devfreq/devfreq.c | 10 +++++++--- drivers/devfreq/governor.h | 2 +- drivers/devfreq/governor_simpleondemand.c | 3 +-- 3 files changed, 9 insertions(+), 6 deletions(-)