[PATCH v8 01/34] opp: Add dev_pm_opp_sync() helper

Dmitry Osipenko
2021-08-17T01:30:22Z

Add dev_pm_opp_sync() helper which syncs OPP table with hardware state
and vice versa.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/opp/core.c | 42 +++++++++++++++++++++++++++++++++++++++---
include/linux/pm_opp.h | 6 ++++++
2 files changed, 45 insertions(+), 3 deletions(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 5543c54dacc5..18016e49605f 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -939,7 +939,8 @@ static int _set_required_opps(struct device *dev,
return ret;
}

-static void _find_current_opp(struct device *dev, struct opp_table *opp_table)
+static struct dev_pm_opp *
+_find_current_opp(struct device *dev, struct opp_table *opp_table)
{
struct dev_pm_opp *opp = ERR_PTR(-ENODEV);
unsigned long freq;
@@ -961,7 +962,7 @@ static void _find_current_opp(struct device *dev, struct opp_table *opp_table)
mutex_unlock(&opp_table->lock);
}

- opp_table->current_opp = opp;
+ return opp;
}

static int _disable_opp_table(struct device *dev, struct opp_table *opp_table)
@@ -1003,7 +1004,7 @@ static int _set_opp(struct device *dev, struct opp_table *opp_table,

/* Find the currently set OPP if we don't know already */
if (unlikely(!opp_table->current_opp))
- _find_current_opp(dev, opp_table);
+ opp_table->current_opp = _find_current_opp(dev, opp_table);

old_opp = opp_table->current_opp;

@@ -2931,3 +2932,38 @@ int dev_pm_opp_sync_regulators(struct device *dev)
return ret;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_sync_regulators);
+
+/**
+ * dev_pm_opp_sync() - Sync OPP state
+ * @dev: device for which we do this operation
+ *
+ * Initialize OPP table accordingly to current clock rate or
+ * first available OPP if clock not available for this device.
+ *
+ * Return: 0 on success or a negative error value.
+ */
+int dev_pm_opp_sync(struct device *dev)
+{
+ struct opp_table *opp_table;
+ struct dev_pm_opp *opp;
+ int ret = 0;
+
+ /* Device may not have OPP table */
+ opp_table = _find_opp_table(dev);
+ if (IS_ERR(opp_table))
+ return 0;
+
+ if (!_get_opp_count(opp_table))
+ goto put_table;
+
+ opp = _find_current_opp(dev, opp_table);
+ ret = _set_opp(dev, opp_table, opp, opp->rate);
+ dev_pm_opp_put(opp);
+
+put_table:
+ /* Drop reference taken by _find_opp_table() */
+ dev_pm_opp_put_opp_table(opp_table);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_sync);
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 84150a22fd7c..686122b59935 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -168,6 +168,7 @@ int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
void dev_pm_opp_remove_table(struct device *dev);
void dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask);
int dev_pm_opp_sync_regulators(struct device *dev);
+int dev_pm_opp_sync(struct device *dev);
#else
static inline struct opp_table *dev_pm_opp_get_opp_table(struct device *dev)
{
@@ -434,6 +435,11 @@ static inline int dev_pm_opp_sync_regulators(struct device *dev)
return -EOPNOTSUPP;
}

+static inline int dev_pm_opp_sync(struct device *dev)
+{
+ return -EOPNOTSUPP;
+}
+
#endif /* CONFIG_PM_OPP */

#if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)
--
2.32.0