NFC: Add a public nfc_hci_send_cmd_async method

This method initiates execution of an HCI cmd. Result will be delivered
through an asynchronous callback.

Signed-off-by: Eric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/include/net/nfc/hci.h b/include/net/nfc/hci.h
index 6f065d5..54ba2ca 100644
--- a/include/net/nfc/hci.h
+++ b/include/net/nfc/hci.h
@@ -200,6 +200,9 @@
 		      const u8 *param, size_t param_len);
 int nfc_hci_send_cmd(struct nfc_hci_dev *hdev, u8 gate, u8 cmd,
 		     const u8 *param, size_t param_len, struct sk_buff **skb);
+int nfc_hci_send_cmd_async(struct nfc_hci_dev *hdev, u8 gate, u8 cmd,
+			   const u8 *param, size_t param_len,
+			   data_exchange_cb_t cb, void *cb_context);
 int nfc_hci_send_response(struct nfc_hci_dev *hdev, u8 gate, u8 response,
 			  const u8 *param, size_t param_len);
 int nfc_hci_send_event(struct nfc_hci_dev *hdev, u8 gate, u8 event,
diff --git a/net/nfc/hci/command.c b/net/nfc/hci/command.c
index 15e2109..71c6a70 100644
--- a/net/nfc/hci/command.c
+++ b/net/nfc/hci/command.c
@@ -28,6 +28,20 @@
 
 #include "hci.h"
 
+static int nfc_hci_execute_cmd_async(struct nfc_hci_dev *hdev, u8 pipe, u8 cmd,
+			       const u8 *param, size_t param_len,
+			       data_exchange_cb_t cb, void *cb_context)
+{
+	pr_debug("exec cmd async through pipe=%d, cmd=%d, plen=%zd\n", pipe,
+		 cmd, param_len);
+
+	/* TODO: Define hci cmd execution delay. Should it be the same
+	 * for all commands?
+	 */
+	return nfc_hci_hcp_message_tx(hdev, pipe, NFC_HCI_HCP_COMMAND, cmd,
+				      param, param_len, cb, cb_context, 3000);
+}
+
 /*
  * HCI command execution completion callback.
  * err will be a standard linux error (may be converted from HCI response)
@@ -60,7 +74,8 @@
 	hcp_ew.exec_complete = false;
 	hcp_ew.result_skb = NULL;
 
-	pr_debug("through pipe=%d, cmd=%d, plen=%zd\n", pipe, cmd, param_len);
+	pr_debug("exec cmd sync through pipe=%d, cmd=%d, plen=%zd\n", pipe,
+		 cmd, param_len);
 
 	/* TODO: Define hci cmd execution delay. Should it be the same
 	 * for all commands?
@@ -138,6 +153,23 @@
 }
 EXPORT_SYMBOL(nfc_hci_send_cmd);
 
+int nfc_hci_send_cmd_async(struct nfc_hci_dev *hdev, u8 gate, u8 cmd,
+			   const u8 *param, size_t param_len,
+			   data_exchange_cb_t cb, void *cb_context)
+{
+	u8 pipe;
+
+	pr_debug("\n");
+
+	pipe = hdev->gate2pipe[gate];
+	if (pipe == NFC_HCI_INVALID_PIPE)
+		return -EADDRNOTAVAIL;
+
+	return nfc_hci_execute_cmd_async(hdev, pipe, cmd, param, param_len,
+					 cb, cb_context);
+}
+EXPORT_SYMBOL(nfc_hci_send_cmd_async);
+
 int nfc_hci_set_param(struct nfc_hci_dev *hdev, u8 gate, u8 idx,
 		      const u8 *param, size_t param_len)
 {