[PATCH 3/4] OPP: Add dev_pm_opp_set_sustainable_opp_freq()

Lukasz Luba
2020-10-28T14:11:16Z

Add a new function allowing to set sustainable OPP from the drivers code.
This is helpful when the device drivers populate the OPP table by
themself.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
---
drivers/opp/core.c | 49 ++++++++++++++++++++++++++++++++++++++++++
include/linux/pm_opp.h | 8 +++++++
2 files changed, 57 insertions(+)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index bb1e68b96d0e..753443f17327 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -325,6 +325,55 @@ unsigned long dev_pm_opp_get_sustainable_opp_freq(struct device *dev)
}
EXPORT_SYMBOL_GPL(dev_pm_opp_get_sustainable_opp_freq);

+/**
+ * dev_pm_opp_set_sustainable_opp_freq() - Find and set the OPP sustainable
+ * based on given frequency
+ * @dev: device for which we do this operation
+ * @freq: frequency which OPP is going to be marked
+ *
+ * Mark the OPP of a given frequency @freq as sustainable_opp. If there is
+ * already sustainable OPP, choose the highest frequency one and set.
+ *
+ * Return: This function return 0 when the new OPP is marked as sustainable
+ * or error return value, which can be:
+ * EINVAL: for bad pointer or no match found for frequency search
+ * EEXIST: if existing sustainable OPP has higher rate
+ */
+int dev_pm_opp_set_sustainable_opp_freq(struct device *dev, unsigned long freq)
+{
+ struct opp_table *opp_table;
+ struct dev_pm_opp *opp;
+ int ret = 0;
+
+ opp = dev_pm_opp_find_freq_exact(dev, freq, true);
+ if (IS_ERR_OR_NULL(opp))
+ return -EINVAL;
+
+ opp_table = _find_opp_table(dev);
+ if (IS_ERR(opp_table))
+ return -EINVAL;
+
+ if (opp_table->sustainable_opp) {
+ /* Pick the OPP with higher rate as sustainable OPP */
+ if (opp->rate > opp_table->sustainable_opp->rate) {
+ opp_table->sustainable_opp->sustainable = false;
+ opp->sustainable = true;
+ opp_table->sustainable_opp = opp;
+ } else {
+ ret = -EEXIST;
+ }
+ } else {
+ opp->sustainable = true;
+ opp_table->sustainable_opp = opp;
+ }
+
+ dev_pm_opp_put(opp);
+ dev_pm_opp_put_opp_table(opp_table);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_sustainable_opp_freq);
+
int _get_opp_count(struct opp_table *opp_table)
{
struct dev_pm_opp *opp;
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 363d5a2c1ef3..e634a6b00e65 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -107,6 +107,8 @@ unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev);
unsigned long dev_pm_opp_get_max_transition_latency(struct device *dev);
unsigned long dev_pm_opp_get_suspend_opp_freq(struct device *dev);
unsigned long dev_pm_opp_get_sustainable_opp_freq(struct device *dev);
+int dev_pm_opp_set_sustainable_opp_freq(struct device *dev,
+ unsigned long freq);

struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
unsigned long freq,
@@ -221,6 +223,12 @@ static inline unsigned long dev_pm_opp_get_sustainable_opp_freq(struct device *d
return 0;
}

+static inline int dev_pm_opp_set_sustainable_freq(struct device *dev,
+ unsigned long freq)
+{
+ return -EOPNOTSUPP;
+}
+
static inline struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
unsigned long freq, bool available)
{
--
2.17.1