1 files changed, 73 insertions, 0 deletions

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 8149e1303e2b..b5c8cb3c96d2 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -58,6 +58,71 @@ static void hci_notify(struct hci_dev *hdev, int event)
 
 /* ---- HCI debugfs entries ---- */
 
+static ssize_t dut_mode_read(struct file *file, char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct hci_dev *hdev = file->private_data;
+	char buf[3];
+
+	buf[0] = test_bit(HCI_DUT_MODE, &hdev->dev_flags) ? 'Y': 'N';
+	buf[1] = '\n';
+	buf[2] = '\0';
+	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
+}
+
+static ssize_t dut_mode_write(struct file *file, const char __user *user_buf,
+			      size_t count, loff_t *ppos)
+{
+	struct hci_dev *hdev = file->private_data;
+	struct sk_buff *skb;
+	char buf[32];
+	size_t buf_size = min(count, (sizeof(buf)-1));
+	bool enable;
+	int err;
+
+	if (!test_bit(HCI_UP, &hdev->flags))
+		return -ENETDOWN;
+
+	if (copy_from_user(buf, user_buf, buf_size))
+		return -EFAULT;
+
+	buf[buf_size] = '\0';
+	if (strtobool(buf, &enable))
+		return -EINVAL;
+
+	if (enable == test_bit(HCI_DUT_MODE, &hdev->dev_flags))
+		return -EALREADY;
+
+	hci_req_lock(hdev);
+	if (enable)
+		skb = __hci_cmd_sync(hdev, HCI_OP_ENABLE_DUT_MODE, 0, NULL,
+				     HCI_CMD_TIMEOUT);
+	else
+		skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL,
+				     HCI_CMD_TIMEOUT);
+	hci_req_unlock(hdev);
+
+	if (IS_ERR(skb))
+		return PTR_ERR(skb);
+
+	err = -bt_to_errno(skb->data[0]);
+	kfree_skb(skb);
+
+	if (err < 0)
+		return err;
+
+	change_bit(HCI_DUT_MODE, &hdev->dev_flags);
+
+	return count;
+}
+
+static const struct file_operations dut_mode_fops = {
+	.open		= simple_open,
+	.read		= dut_mode_read,
+	.write		= dut_mode_write,
+	.llseek		= default_llseek,
+};
+
 static int features_show(struct seq_file *f, void *ptr)
 {
 	struct hci_dev *hdev = f->private;
@@ -1256,6 +1321,14 @@ static int __hci_init(struct hci_dev *hdev)
 	if (err < 0)
 		return err;
 
+	/* The Device Under Test (DUT) mode is special and available for
+	 * all controller types. So just create it early on.
+	 */
+	if (test_bit(HCI_SETUP, &hdev->dev_flags)) {
+		debugfs_create_file("dut_mode", 0644, hdev->debugfs, hdev,
+				    &dut_mode_fops);
+	}
+
 	/* HCI_BREDR covers both single-mode LE, BR/EDR and dual-mode
 	 * BR/EDR/LE type controllers. AMP controllers only need the
 	 * first stage init.