[PATCH v2 2/2] PM / devfreq: Add suspend frequency support
From: Chanwoo Choi
Date: Wed Dec 28 2016 - 07:07:43 EST
From: Lin Huang <hl@xxxxxxxxxxxxxx>
Add suspend frequency support and if needed set it to
the frequency obtained from the suspend opp (can be defined
using opp-v2 bindings and is optional).
Signed-off-by: Lin Huang <hl@xxxxxxxxxxxxxx>
[cw00.choi: Support the passive governor and use separate devfreq_set_target()]
Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
---
drivers/devfreq/devfreq.c | 31 ++++++++++++++++++++++++++++++-
include/linux/devfreq.h | 2 ++
2 files changed, 32 insertions(+), 1 deletion(-)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index e386f14d91c3..8109fb71177b 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -620,6 +620,23 @@ struct devfreq *devfreq_add_device(struct device *dev,
goto err_init;
}
+ /*
+ * Get the suspend frequency from OPP table. But the devfreq device
+ * using passive governor don't need to get the suspend frequency
+ * because the passive devfreq device depend on the parent devfreq
+ * device.
+ */
+ devfreq->suspend_freq = 0L;
+ if (strncmp(devfreq->governor_name, "passive", 7)) {
+ struct dev_pm_opp *opp;
+
+ rcu_read_lock();
+ opp = dev_pm_opp_get_suspend_opp(dev);
+ if (opp)
+ devfreq->suspend_freq = dev_pm_opp_get_freq(opp);
+ rcu_read_unlock();
+ }
+
devfreq->governor = governor;
err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START,
NULL);
@@ -777,14 +794,26 @@ void devm_devfreq_remove_device(struct device *dev, struct devfreq *devfreq)
*/
int devfreq_suspend_device(struct devfreq *devfreq)
{
+ int ret;
+
if (!devfreq)
return -EINVAL;
if (!devfreq->governor)
return 0;
- return devfreq->governor->event_handler(devfreq,
+ ret = devfreq->governor->event_handler(devfreq,
DEVFREQ_GOV_SUSPEND, NULL);
+ if (ret < 0)
+ return ret;
+
+ if (devfreq->suspend_freq) {
+ ret = devfreq_set_target(devfreq, devfreq->suspend_freq, 0);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
}
EXPORT_SYMBOL(devfreq_suspend_device);
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 2de4e2eea180..926bef5a6332 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -141,6 +141,7 @@ struct devfreq_governor {
* devfreq.nb to the corresponding register notifier call chain.
* @work: delayed work for load monitoring.
* @previous_freq: previously configured frequency value.
+ * @suspend_freq: frequency to set during suspend mode.
* @data: Private data of the governor. The devfreq framework does not
* touch this.
* @min_freq: Limit minimum frequency requested by user (0: none)
@@ -172,6 +173,7 @@ struct devfreq {
struct delayed_work work;
unsigned long previous_freq;
+ unsigned long suspend_freq;
struct devfreq_dev_status last_status;
void *data; /* private data for governors */
--
1.9.1