[PATCH v1 3/3] PM / devfreq: Add required OPPs support to passive governor

[Saravana Kannan]

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 <sarava...@google.com>
---
 drivers/devfreq/governor_passive.c | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/devfreq/governor_passive.c 
b/drivers/devfreq/governor_passive.c
index 3bc29acbd54e..bd4a98bb15b1 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -21,8 +21,9 @@ static int devfreq_passive_get_target_freq(struct devfreq 
*devfreq,
        struct devfreq_passive_data *p_data
                        = (struct devfreq_passive_data *)devfreq->data;
        struct devfreq *parent_devfreq = (struct devfreq *)p_data->parent;
+       struct opp_table *opp_table = NULL, *c_opp_table = NULL;
        unsigned long child_freq = ULONG_MAX;
-       struct dev_pm_opp *opp;
+       struct dev_pm_opp *opp = NULL, *c_opp = NULL;
        int i, count, ret = 0;
 
        /*
@@ -65,7 +66,20 @@ static int devfreq_passive_get_target_freq(struct devfreq 
*devfreq,
                goto out;
        }
 
-       dev_pm_opp_put(opp);
+       opp_table = dev_pm_opp_get_opp_table(parent_devfreq->dev.parent);
+       if (IS_ERR_OR_NULL(opp_table)) {
+               ret = PTR_ERR(opp_table);
+               goto out;
+       }
+
+       c_opp_table = dev_pm_opp_get_opp_table(devfreq->dev.parent);
+       if (!IS_ERR_OR_NULL(c_opp_table))
+               c_opp = dev_pm_opp_xlate_opp(opp_table, c_opp_table, opp);
+       if (c_opp) {
+               *freq = dev_pm_opp_get_freq(c_opp);
+               dev_pm_opp_put(c_opp);
+               goto out;
+       }
 
        /*
         * Get the OPP table's index of decided freqeuncy by governor
@@ -92,6 +106,13 @@ static int devfreq_passive_get_target_freq(struct devfreq 
*devfreq,
        *freq = child_freq;
 
 out:
+       if (!IS_ERR_OR_NULL(opp_table))
+               dev_pm_opp_put_opp_table(opp_table);
+       if (!IS_ERR_OR_NULL(c_opp_table))
+               dev_pm_opp_put_opp_table(c_opp_table);
+       if (!IS_ERR_OR_NULL(opp))
+               dev_pm_opp_put(opp);
+
        return ret;
 }
 
-- 
2.22.0.410.gd8fdbe21b5-goog