[PATCH v1 1/3] mailbox: Provide devm variants for mbox_request_channel{,_byname}()

[Uwe Kleine-König]

The new functions devm_mbox_request_channel() and
devm_mbox_request_channel_byname() allow to simplify resource management
for callers in their .probe() and .remove() functions.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxx>
---
 drivers/mailbox/mailbox.c      | 44 ++++++++++++++++++++++++++++++++++
 include/linux/mailbox_client.h |  5 ++++
 2 files changed, 49 insertions(+)

diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index efacd24a085d..f51b4ca02041 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -490,6 +490,31 @@ struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index)
 }
 EXPORT_SYMBOL_GPL(mbox_request_channel);
 
+static void devm_mbox_free_channel(void *data)
+{
+	struct mbox_chan *chan = data;
+
+	mbox_free_channel(chan);
+}
+
+struct mbox_chan *devm_mbox_request_channel(struct device *dev,
+					    struct mbox_client *cl, int index)
+{
+	struct mbox_chan *chan;
+	int ret;
+
+	chan = mbox_request_channel(cl, index);
+	if (IS_ERR(chan))
+		return chan;
+
+	ret = devm_add_action_or_reset(dev, devm_mbox_free_channel, chan);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return chan;
+}
+EXPORT_SYMBOL_GPL(devm_mbox_request_channel);
+
 struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,
 					      const char *name)
 {
@@ -504,6 +529,25 @@ struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,
 }
 EXPORT_SYMBOL_GPL(mbox_request_channel_byname);
 
+struct mbox_chan *devm_mbox_request_channel_byname(struct device *dev,
+						   struct mbox_client *cl,
+						   const char *name)
+{
+	struct mbox_chan *chan;
+	int ret;
+
+	chan = mbox_request_channel_byname(cl, name);
+	if (IS_ERR(chan))
+		return chan;
+
+	ret = devm_add_action_or_reset(dev, devm_mbox_free_channel, chan);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return chan;
+}
+EXPORT_SYMBOL_GPL(devm_mbox_request_channel_byname);
+
 /**
  * mbox_free_channel - The client relinquishes control of a mailbox
  *			channel by this call.
diff --git a/include/linux/mailbox_client.h b/include/linux/mailbox_client.h
index e5997120f45c..ce550a93bf61 100644
--- a/include/linux/mailbox_client.h
+++ b/include/linux/mailbox_client.h
@@ -40,7 +40,12 @@ struct mbox_client {
 int mbox_bind_client(struct mbox_chan *chan, struct mbox_client *cl);
 struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl,
 					      const char *name);
+struct mbox_chan *devm_mbox_request_channel_byname(struct device *dev,
+						   struct mbox_client *cl,
+						   const char *name);
 struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index);
+struct mbox_chan *devm_mbox_request_channel(struct device *dev,
+					    struct mbox_client *cl, int index);
 int mbox_send_message(struct mbox_chan *chan, void *mssg);
 int mbox_flush(struct mbox_chan *chan, unsigned long timeout);
 void mbox_client_txdone(struct mbox_chan *chan, int r); /* atomic */
-- 
2.47.3