[PATCH 02/12] OPP: Add function to look up required OPP's for a given OPP

Andrew-sh.Cheng
2020-05-20T03:52:55Z

From: Saravana Kannan <saravanak@google.com>

Add a function that allows looking up required OPPs given a source OPP
table, destination OPP table and the source OPP.

Signed-off-by: Saravana Kannan <saravanak@google.com>
---
drivers/opp/core.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/pm_opp.h | 11 +++++++++++
2 files changed, 64 insertions(+)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 51403c1f2481..64666d3eaf5b 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -1923,6 +1923,59 @@ void dev_pm_opp_detach_genpd(struct opp_table *opp_table)
EXPORT_SYMBOL_GPL(dev_pm_opp_detach_genpd);

/**
+ * dev_pm_opp_xlate_required_opp() - Find required OPP for @src_table OPP.
+ * @src_table: OPP table which has @dst_table as one of its required OPP table.
+ * @dst_table: Required OPP table of the @src_table.
+ *
+ * This function returns the OPP (present in @dst_table) pointed out by the
+ * "required-opps" property of the OPP (present in @src_table).
+ *
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
+ *
+ * Return: destination table OPP on success, otherwise NULL on errors.
+ */
+struct dev_pm_opp *dev_pm_opp_xlate_required_opp(struct opp_table *src_table,
+ struct opp_table *dst_table,
+ struct dev_pm_opp *src_opp)
+{
+ struct dev_pm_opp *opp, *dest_opp = NULL;
+ int i;
+
+ if (!src_table || !dst_table || !src_opp)
+ return NULL;
+
+ for (i = 0; i < src_table->required_opp_count; i++) {
+ if (src_table->required_opp_tables[i]->np == dst_table->np)
+ break;
+ }
+
+ if (unlikely(i == src_table->required_opp_count)) {
+ pr_err("%s: Couldn't find matching OPP table (%p: %p)\n",
+ __func__, src_table, dst_table);
+ return NULL;
+ }
+
+ mutex_lock(&src_table->lock);
+
+ list_for_each_entry(opp, &src_table->opp_list, node) {
+ if (opp == src_opp) {
+ dest_opp = opp->required_opps[i];
+ dev_pm_opp_get(dest_opp);
+ goto unlock;
+ }
+ }
+
+ pr_err("%s: Couldn't find matching OPP (%p: %p)\n", __func__, src_table,
+ dst_table);
+
+unlock:
+ mutex_unlock(&src_table->lock);
+
+ return dest_opp;
+}
+
+/**
* dev_pm_opp_xlate_performance_state() - Find required OPP's pstate for src_table.
* @src_table: OPP table which has dst_table as one of its required OPP table.
* @dst_table: Required OPP table of the src_table.
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 747861816f4f..909cf7563d35 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -137,6 +137,9 @@ struct opp_table *dev_pm_opp_register_set_opp_helper(struct device *dev, int (*s
void dev_pm_opp_unregister_set_opp_helper(struct opp_table *opp_table);
struct opp_table *dev_pm_opp_attach_genpd(struct device *dev, const char **names, struct device ***virt_devs);
void dev_pm_opp_detach_genpd(struct opp_table *opp_table);
+struct dev_pm_opp *dev_pm_opp_xlate_required_opp(struct opp_table *src_table,
+ struct opp_table *dst_table,
+ struct dev_pm_opp *src_opp);
int dev_pm_opp_xlate_performance_state(struct opp_table *src_table, struct opp_table *dst_table, unsigned int pstate);
int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq);
int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const struct cpumask *cpumask);
@@ -320,6 +323,14 @@ static inline struct opp_table *dev_pm_opp_attach_genpd(struct device *dev, cons

static inline void dev_pm_opp_detach_genpd(struct opp_table *opp_table) {}

+static inline struct dev_pm_opp *dev_pm_opp_xlate_required_opp(
+ struct opp_table *src_table,
+ struct opp_table *dst_table,
+ struct dev_pm_opp *src_opp)
+{
+ return NULL;
+}
+
static inline int dev_pm_opp_xlate_performance_state(struct opp_table *src_table, struct opp_table *dst_table, unsigned int pstate)
{
return -ENOTSUPP;
--
2.12.5