mt76: implement functions to get the response skb for MCU calls

Can be used by the caller to get the response data directly instead of using the
hack of storing the result in internal data structures from .mcu_parse_response
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mcu.c

@@ -51,8 +51,8 @@ void mt76_mcu_rx_event(struct mt76_dev *dev, struct sk_buff *skb)
 }
 EXPORT_SYMBOL_GPL(mt76_mcu_rx_event);
 
-int mt76_mcu_send_msg(struct mt76_dev *dev, int cmd, const void *data,
-		      int len, bool wait_resp)
+int mt76_mcu_send_and_get_msg(struct mt76_dev *dev, int cmd, const void *data,
+			      int len, bool wait_resp, struct sk_buff **ret_skb)
 {
 	struct sk_buff *skb;
 
@@ -63,16 +63,20 @@ int mt76_mcu_send_msg(struct mt76_dev *dev, int cmd, const void *data,
 	if (!skb)
 		return -ENOMEM;
 
-	return mt76_mcu_skb_send_msg(dev, skb, cmd, wait_resp);
+	return mt76_mcu_skb_send_and_get_msg(dev, skb, cmd, wait_resp, ret_skb);
 }
-EXPORT_SYMBOL_GPL(mt76_mcu_send_msg);
+EXPORT_SYMBOL_GPL(mt76_mcu_send_and_get_msg);
 
-int mt76_mcu_skb_send_msg(struct mt76_dev *dev, struct sk_buff *skb,
-			  int cmd, bool wait_resp)
+int mt76_mcu_skb_send_and_get_msg(struct mt76_dev *dev, struct sk_buff *skb,
+				  int cmd, bool wait_resp,
+				  struct sk_buff **ret_skb)
 {
 	unsigned long expires;
 	int ret, seq;
 
+	if (ret_skb)
+		*ret_skb = NULL;
+
 	mutex_lock(&dev->mcu.mutex);
 
 	ret = dev->mcu_ops->mcu_skb_send_msg(dev, skb, cmd, &seq);
@@ -89,7 +93,10 @@ int mt76_mcu_skb_send_msg(struct mt76_dev *dev, struct sk_buff *skb,
 	do {
 		skb = mt76_mcu_get_response(dev, expires);
 		ret = dev->mcu_ops->mcu_parse_response(dev, cmd, skb, seq);
-		dev_kfree_skb(skb);
+		if (!ret && ret_skb)
+			*ret_skb = skb;
+		else
+			dev_kfree_skb(skb);
 	} while (ret == -EAGAIN);
 
 out:
@@ -97,4 +104,4 @@ int mt76_mcu_skb_send_msg(struct mt76_dev *dev, struct sk_buff *skb,
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(mt76_mcu_skb_send_msg);
+EXPORT_SYMBOL_GPL(mt76_mcu_skb_send_and_get_msg);

drivers/net/wireless/mediatek/mt76/mt76.h

@@ -1067,10 +1067,23 @@ mt76_mcu_msg_alloc(struct mt76_dev *dev, const void *data,
 void mt76_mcu_rx_event(struct mt76_dev *dev, struct sk_buff *skb);
 struct sk_buff *mt76_mcu_get_response(struct mt76_dev *dev,
 				      unsigned long expires);
-int mt76_mcu_send_msg(struct mt76_dev *dev, int cmd, const void *data,
-		      int len, bool wait_resp);
-int mt76_mcu_skb_send_msg(struct mt76_dev *dev, struct sk_buff *skb,
-			  int cmd, bool wait_resp);
+int mt76_mcu_send_and_get_msg(struct mt76_dev *dev, int cmd, const void *data,
+			      int len, bool wait_resp, struct sk_buff **ret);
+int mt76_mcu_skb_send_and_get_msg(struct mt76_dev *dev, struct sk_buff *skb,
+				  int cmd, bool wait_resp, struct sk_buff **ret);
+static inline int
+mt76_mcu_send_msg(struct mt76_dev *dev, int cmd, const void *data, int len,
+		  bool wait_resp)
+{
+	return mt76_mcu_send_and_get_msg(dev, cmd, data, len, wait_resp, NULL);
+}
+
+static inline int
+mt76_mcu_skb_send_msg(struct mt76_dev *dev, struct sk_buff *skb, int cmd,
+		      bool wait_resp)
+{
+	return mt76_mcu_skb_send_and_get_msg(dev, skb, cmd, wait_resp, NULL);
+}
 
 void mt76_set_irq_mask(struct mt76_dev *dev, u32 addr, u32 clear, u32 set);