pmic-voter: add support to report override votes

Add support to report if a votable is voted via override
voting mechanism.
While at it, add valid pointer checks in global voter functions.

Change-Id: Ib867144c92f4ae99d9391190f75c8a6c95a3f4f0
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>

drivers/power/supply/qcom/pmic-voter.c

@@ -166,7 +166,7 @@ static int get_client_id(struct votable *votable, const char *client_str)
 
 static char *get_client_str(struct votable *votable, int client_id)
 {
-	if (client_id == -EINVAL)
+	if (!votable || (client_id == -EINVAL))
 		return NULL;
 
 	return votable->client_strs[client_id];
@@ -182,6 +182,38 @@ void unlock_votable(struct votable *votable)
 	mutex_unlock(&votable->vote_lock);
 }
 
+/**
+ * is_override_vote_enabled() -
+ * is_override_vote_enabled_locked() -
+ *		The unlocked and locked variants of getting whether override
+		vote is enabled.
+ * @votable:	the votable object
+ *
+ * Returns:
+ *	True if the client's vote is enabled; false otherwise.
+ */
+bool is_override_vote_enabled_locked(struct votable *votable)
+{
+	if (!votable)
+		return false;
+
+	return votable->override_result != -EINVAL;
+}
+
+bool is_override_vote_enabled(struct votable *votable)
+{
+	bool enable;
+
+	if (!votable)
+		return false;
+
+	lock_votable(votable);
+	enable = is_override_vote_enabled_locked(votable);
+	unlock_votable(votable);
+
+	return enable;
+}
+
 /**
  * is_client_vote_enabled() -
  * is_client_vote_enabled_locked() -
@@ -196,8 +228,13 @@ void unlock_votable(struct votable *votable)
 bool is_client_vote_enabled_locked(struct votable *votable,
 							const char *client_str)
 {
-	int client_id = get_client_id(votable, client_str);
 
+	int client_id;
+
+	if (!votable || !client_str)
+		return false;
+
+	client_id = get_client_id(votable, client_str);
 	if (client_id < 0)
 		return false;
 
@@ -208,6 +245,9 @@ bool is_client_vote_enabled(struct votable *votable, const char *client_str)
 {
 	bool enabled;
 
+	if (!votable || !client_str)
+		return false;
+
 	lock_votable(votable);
 	enabled = is_client_vote_enabled_locked(votable, client_str);
 	unlock_votable(votable);
@@ -228,8 +268,12 @@ bool is_client_vote_enabled(struct votable *votable, const char *client_str)
  */
 int get_client_vote_locked(struct votable *votable, const char *client_str)
 {
-	int client_id = get_client_id(votable, client_str);
+	int client_id;
 
+	if (!votable || !client_str)
+		return -EINVAL;
+
+	client_id = get_client_id(votable, client_str);
 	if (client_id < 0)
 		return -EINVAL;
 
@@ -244,6 +288,9 @@ int get_client_vote(struct votable *votable, const char *client_str)
 {
 	int value;
 
+	if (!votable || !client_str)
+		return -EINVAL;
+
 	lock_votable(votable);
 	value = get_client_vote_locked(votable, client_str);
 	unlock_votable(votable);
@@ -269,6 +316,9 @@ int get_client_vote(struct votable *votable, const char *client_str)
  */
 int get_effective_result_locked(struct votable *votable)
 {
+	if (!votable)
+		return -EINVAL;
+
 	if (votable->force_active)
 		return votable->force_val;
 
@@ -282,6 +332,9 @@ int get_effective_result(struct votable *votable)
 {
 	int value;
 
+	if (!votable)
+		return -EINVAL;
+
 	lock_votable(votable);
 	value = get_effective_result_locked(votable);
 	unlock_votable(votable);
@@ -308,6 +361,9 @@ int get_effective_result(struct votable *votable)
  */
 const char *get_effective_client_locked(struct votable *votable)
 {
+	if (!votable)
+		return NULL;
+
 	if (votable->force_active)
 		return DEBUG_FORCE_CLIENT;
 
@@ -321,6 +377,9 @@ const char *get_effective_client(struct votable *votable)
 {
 	const char *client_str;
 
+	if (!votable)
+		return NULL;
+
 	lock_votable(votable);
 	client_str = get_effective_client_locked(votable);
 	unlock_votable(votable);
@@ -358,6 +417,9 @@ int vote(struct votable *votable, const char *client_str, bool enabled, int val)
 	int rc = 0;
 	bool similar_vote = false;
 
+	if (!votable || !client_str)
+		return -EINVAL;
+
 	lock_votable(votable);
 
 	client_id = get_client_id(votable, client_str);
@@ -463,6 +525,9 @@ int vote_override(struct votable *votable, const char *override_client,
 {
 	int rc = 0;
 
+	if (!votable || !override_client)
+		return -EINVAL;
+
 	lock_votable(votable);
 	if (votable->force_active) {
 		votable->override_result = enabled ? val : -EINVAL;
@@ -493,6 +558,9 @@ int rerun_election(struct votable *votable)
 	int rc = 0;
 	int effective_result;
 
+	if (!votable)
+		return -EINVAL;
+
 	lock_votable(votable);
 	effective_result = get_effective_result_locked(votable);
 	if (votable->callback)
@@ -510,6 +578,9 @@ struct votable *find_votable(const char *name)
 	struct votable *v;
 	bool found = false;
 
+	if (!name)
+		return NULL;
+
 	spin_lock_irqsave(&votable_list_slock, flags);
 	if (list_empty(&votable_list))
 		goto out;
@@ -642,6 +713,9 @@ struct votable *create_votable(const char *name,
 	struct votable *votable;
 	unsigned long flags;
 
+	if (!name)
+		return ERR_PTR(-EINVAL);
+
 	votable = find_votable(name);
 	if (votable)
 		return ERR_PTR(-EEXIST);

include/linux/pmic-voter.h

@@ -21,6 +21,8 @@ enum votable_type {
 bool is_client_vote_enabled(struct votable *votable, const char *client_str);
 bool is_client_vote_enabled_locked(struct votable *votable,
 							const char *client_str);
+bool is_override_vote_enabled(struct votable *votable);
+bool is_override_vote_enabled_locked(struct votable *votable);
 int get_client_vote(struct votable *votable, const char *client_str);
 int get_client_vote_locked(struct votable *votable, const char *client_str);
 int get_effective_result(struct votable *votable);