tty: n_gsm: introduce gsm_control_command() function

Move the content of gsm_control_transmit() to a new function
gsm_control_command() with a more generic signature and analog to
gsm_control_reply(). Use this within gsm_control_transmit().

This is needed to simplify upcoming functional additions.

Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220831073800.7459-4-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index c5445d3..feff205 100644 (file)
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -1314,6 +1314,31 @@ static void gsm_dlci_data_kick(struct gsm_dlci *dlci)
 
 
 /**
+ * gsm_control_command -       send a command frame to a control
+ * @gsm: gsm channel
+ * @cmd: the command to use
+ * @data: data to follow encoded info
+ * @dlen: length of data
+ *
+ * Encode up and queue a UI/UIH frame containing our command.
+ */
+static int gsm_control_command(struct gsm_mux *gsm, int cmd, const u8 *data,
+                              int dlen)
+{
+       struct gsm_msg *msg = gsm_data_alloc(gsm, 0, dlen + 2, gsm->ftype);
+
+       if (msg == NULL)
+               return -ENOMEM;
+
+       msg->data[0] = (cmd << 1) | CR | EA;    /* Set C/R */
+       msg->data[1] = (dlen << 1) | EA;
+       memcpy(msg->data + 2, data, dlen);
+       gsm_data_queue(gsm->dlci[0], msg);
+
+       return 0;
+}
+
+/**
  *     gsm_control_reply       -       send a response frame to a control
  *     @gsm: gsm channel
  *     @cmd: the command to use
@@ -1618,13 +1643,7 @@ static void gsm_control_response(struct gsm_mux *gsm, unsigned int command,
 
 static void gsm_control_transmit(struct gsm_mux *gsm, struct gsm_control *ctrl)
 {
-       struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 2, gsm->ftype);
-       if (msg == NULL)
-               return;
-       msg->data[0] = (ctrl->cmd << 1) | CR | EA;      /* command */
-       msg->data[1] = (ctrl->len << 1) | EA;
-       memcpy(msg->data + 2, ctrl->data, ctrl->len);
-       gsm_data_queue(gsm->dlci[0], msg);
+       gsm_control_command(gsm, ctrl->cmd, ctrl->data, ctrl->len);
 }
 
 /**