[PATCH v6 3/3] PM / devfreq: Add required OPPs support to passive governor

From: Hsin-Yi Wang
Date: Thu Feb 04 2021 - 03:16:00 EST


From: Saravana Kannan <saravanak@xxxxxxxxxx>

Look at the required OPPs of the "parent" device to determine the OPP that
is required from the slave device managed by the passive governor. This
allows having mappings between a parent device and a slave device even when
they don't have the same number of OPPs.

Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx>
Acked-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
Acked-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
Signed-off-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx>
---
drivers/devfreq/governor_passive.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
index 63332e4a65ae8..8fd51cc9b991a 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -19,7 +19,7 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
= (struct devfreq_passive_data *)devfreq->data;
struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
unsigned long child_freq = ULONG_MAX;
- struct dev_pm_opp *opp;
+ struct dev_pm_opp *opp, *p_opp = ERR_PTR(-ENODEV);
int i, count, ret = 0;

/*
@@ -29,7 +29,7 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
*/
if (p_data->get_target_freq) {
ret = p_data->get_target_freq(devfreq, freq);
- goto out;
+ return ret;
}

/*
@@ -56,13 +56,22 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
* list of parent device. Because in this case, *freq is temporary
* value which is decided by ondemand governor.
*/
- opp = devfreq_recommended_opp(parent_devfreq->dev.parent, freq, 0);
- if (IS_ERR(opp)) {
- ret = PTR_ERR(opp);
- goto out;
+ p_opp = devfreq_recommended_opp(parent_devfreq->dev.parent, freq, 0);
+ if (IS_ERR(p_opp)) {
+ ret = PTR_ERR(p_opp);
+ return ret;
}

- dev_pm_opp_put(opp);
+ if (devfreq->opp_table && parent_devfreq->opp_table) {
+ opp = dev_pm_opp_xlate_required_opp(parent_devfreq->opp_table,
+ devfreq->opp_table, p_opp);
+ if (!IS_ERR(opp)) {
+ *freq = dev_pm_opp_get_freq(opp);
+ dev_pm_opp_put(opp);
+ } else
+ ret = PTR_ERR(opp);
+ goto out;
+ }

/*
* Get the OPP table's index of decided freqeuncy by governor
@@ -89,6 +98,8 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
*freq = child_freq;

out:
+ dev_pm_opp_put(p_opp);
+
return ret;
}

--
2.30.0.365.g02bc693789-goog