[PATCH V2] cpufreq: drivers with target_index() must set freq_table

[Viresh Kumar]

Since the cpufreq core directly uses freq_table, for cpufreq drivers
that set their target_index() callback, make it mandatory for them to
set the same.

Since this is set per policy and normally from policy->init(), do this
from cpufreq_table_validate_and_sort() which gets called right after
->init().

Reported-by: Yajun Deng <yajun.deng@xxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
V2: Move declaration to cpufreq.h.

 drivers/cpufreq/cpufreq.c    | 5 +++++
 drivers/cpufreq/freq_table.c | 7 ++++++-
 include/linux/cpufreq.h      | 1 +
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 6d8fd3b8dcb5..09131c54703f 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -73,6 +73,11 @@ static inline bool has_target(void)
 	return cpufreq_driver->target_index || cpufreq_driver->target;
 }
 
+bool has_target_index(void)
+{
+	return !!cpufreq_driver->target_index;
+}
+
 /* internal prototypes */
 static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
 static int cpufreq_init_governor(struct cpufreq_policy *policy);
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
index 90bfc27ed1ba..c4d4643b6ca6 100644
--- a/drivers/cpufreq/freq_table.c
+++ b/drivers/cpufreq/freq_table.c
@@ -355,8 +355,13 @@ int cpufreq_table_validate_and_sort(struct cpufreq_policy *policy)
 {
 	int ret;
 
-	if (!policy->freq_table)
+	if (!policy->freq_table) {
+		/* Freq table must be passed by drivers with target_index() */
+		if (has_target_index())
+			return -EINVAL;
+
 		return 0;
+	}
 
 	ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table);
 	if (ret)
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 65623233ab2f..541013487a0e 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -237,6 +237,7 @@ bool cpufreq_supports_freq_invariance(void);
 struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
 void cpufreq_enable_fast_switch(struct cpufreq_policy *policy);
 void cpufreq_disable_fast_switch(struct cpufreq_policy *policy);
+bool has_target_index(void);
 #else
 static inline unsigned int cpufreq_get(unsigned int cpu)
 {
-- 
2.31.1.272.g89b43f80a514