Hi Chanwoo Choi,
On 2016年11月08日 17:32, Chanwoo Choi wrote:
Hi Lin,
On 2016년 11월 08일 18:11, Lin Huang wrote:
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 <[email protected]>
---
Changes in v2:
- use update_devfreq() instead devfreq_update_status()
Changes in v3:
- fix build error
Changes in v4:
- move dev_pm_opp_get_suspend_opp() to devfreq_add_device()
drivers/devfreq/devfreq.c | 15 +++++++++++++--
drivers/devfreq/governor_simpleondemand.c | 9 +++++++++
include/linux/devfreq.h | 9 +++++++++
3 files changed, 31 insertions(+), 2 deletions(-)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index bf3ea76..d9d56e1 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -363,7 +363,10 @@ void devfreq_monitor_suspend(struct devfreq *devfreq)
mutex_unlock(&devfreq->lock);
return;
}
-
+ if (devfreq->suspend_freq) {
+ update_devfreq(devfreq);
+ devfreq->suspend_flag = true;
You don't need the additional variable (devfreq->suspend_flag).
When adding the devfreq on devfreq_add_device(),
you can initialize the devfreq->suspend_freq as zero(0).
You can check whether devfreq->suspend_freq is 0 or not
without the new suspend_flag.
+ }
devfreq_update_status(devfreq, devfreq->previous_freq);
devfreq->stop_polling = true;
mutex_unlock(&devfreq->lock);
@@ -394,7 +397,8 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
devfreq->last_stat_updated = jiffies;
devfreq->stop_polling = false;
-
+ if (devfreq->suspend_freq)
+ devfreq->suspend_flag = false;
ditto. You don't need to add this code.
if (devfreq->profile->get_cur_freq &&
!devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq))
devfreq->previous_freq = freq;
@@ -528,6 +532,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
struct devfreq *devfreq;
struct devfreq_governor *governor;
int err = 0;
+ struct dev_pm_opp *suspend_opp;
if (!dev || !profile || !governor_name) {
dev_err(dev, "%s: Invalid parameters.\n", __func__);
@@ -563,6 +568,12 @@ struct devfreq *devfreq_add_device(struct device *dev,
devfreq->data = data;
devfreq->nb.notifier_call = devfreq_notifier_call;
+ rcu_read_lock();
+ suspend_opp = dev_pm_opp_get_suspend_opp(dev);
+ if (suspend_opp)
+ devfreq->suspend_freq = dev_pm_opp_get_freq(suspend_opp);
+ rcu_read_unlock();
+
if (!devfreq->profile->max_state && !devfreq->profile->freq_table) {
mutex_unlock(&devfreq->lock);
devfreq_set_freq_table(devfreq);
diff --git a/drivers/devfreq/governor_simpleondemand.c
b/drivers/devfreq/governor_simpleondemand.c
index ae72ba5..84b3ce1 100644
--- a/drivers/devfreq/governor_simpleondemand.c
+++ b/drivers/devfreq/governor_simpleondemand.c
@@ -29,6 +29,15 @@ static int devfreq_simple_ondemand_func(struct devfreq *df,
struct devfreq_simple_ondemand_data *data = df->data;
unsigned long max = (df->max_freq) ? df->max_freq : UINT_MAX;
+ /*
+ * if devfreq in suspend status and have suspend_freq,
+ * the frequency need to set to suspend_freq
+ */
+ if (df->suspend_flag) {
+ *freq = df->suspend_freq;
+ return 0;
+ }
You can check it as following:
if (df->suspend_freq != 0)
*freq = df->suspend_freq;
If i do like this, it will always return suspend frequency, since
devfreq->suspend_freq will be assigned value
if we define it on dts. But what we want is only in suspend status we
return the suspend frequency.
+
err = devfreq_update_stats(df);
if (err)
return err;
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 2de4e2e..c463ae1 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -172,6 +172,7 @@ 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 */
@@ -179,6 +180,7 @@ struct devfreq {
unsigned long min_freq;
unsigned long max_freq;
bool stop_polling;
+ bool suspend_flag;
You don't need to add new variable.
/* information for device frequency transition */
unsigned int total_trans;
@@ -214,6 +216,8 @@ extern int devfreq_resume_device(struct devfreq *devfreq);
/* Helper functions for devfreq user device driver with OPP. */
extern struct dev_pm_opp *devfreq_recommended_opp(struct device *dev,
unsigned long *freq, u32 flags);
+extern void devfreq_opp_get_suspend_opp(struct device *dev,
+ struct devfreq *devfreq);
Why do you need this function? Also, this patch don't include the body
of devfreq_opp_get_suspend_opp() function.
Oh, forget to delete it, sorry about that.
extern int devfreq_register_opp_notifier(struct device *dev,
struct devfreq *devfreq);
extern int devfreq_unregister_opp_notifier(struct device *dev,
@@ -348,6 +352,11 @@ static inline struct dev_pm_opp
*devfreq_recommended_opp(struct device *dev,
return ERR_PTR(-EINVAL);
}
+static inline void devfreq_opp_get_suspend_opp(struct device *dev,
+ struct devfreq *devfreq)
+{
+}
+
static inline int devfreq_register_opp_notifier(struct device *dev,
struct devfreq *devfreq)
{
--
Lin Huang
