[PATCH 4/6] tty: n_gsm: introduce gsm_control_command() function

From: D. Starke
Date: Mon Aug 22 2022 - 03:24:27 EST


From: Daniel Starke <daniel.starke@xxxxxxxxxxx>

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@xxxxxxxxxxx>
---
drivers/tty/n_gsm.c | 30 +++++++++++++++++++++++-------
1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index c87525b70e81..71599198eb6d 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -1316,6 +1316,28 @@ 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, 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
@@ -1623,13 +1645,7 @@ 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);
}

/**
--
2.34.1