[RFC PATCH 09/13] can: slcan: send the close command to the adapter

From: Dario Binacchi
Date: Tue Jun 07 2022 - 05:49:48 EST


In case the bitrate has been set via ip tool, it sends the close command
("C\r") to the adapter.

Signed-off-by: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>
---

drivers/net/can/slcan.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index f18097c62222..d63d270d21da 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -438,9 +438,20 @@ static int slcan_transmit_cmd(struct slcan *sl, const unsigned char *cmd)
static int slc_close(struct net_device *dev)
{
struct slcan *sl = netdev_priv(dev);
+ int err;

spin_lock_bh(&sl->lock);
if (sl->tty) {
+ if (sl->can.bittiming.bitrate &&
+ sl->can.bittiming.bitrate != -1) {
+ spin_unlock_bh(&sl->lock);
+ err = slcan_transmit_cmd(sl, "C\r");
+ spin_lock_bh(&sl->lock);
+ if (err)
+ netdev_warn(dev,
+ "failed to send close command 'C\\r'\n");
+ }
+
/* TTY discipline is running. */
clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
}
--
2.32.0