It allows to set the bitrate via ip tool, as it happens for the other
CAN device drivers. It still remains possible to set the bitrate via
slcand or slcan_attach utilities. In case the ip tool is used, the
driver will send the serial command to the adapter.
Signed-off-by: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>
---
Changes in v2:
- Use the CAN framework support for setting fixed bit rates.
drivers/net/can/slcan.c | 39 ++++++++++++++++++++++++++++++++++++++-
1 file changed, 38 insertions(+), 1 deletion(-)
diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index cab0a2a8c84c..8561bcee81ba 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -439,6 +439,7 @@ static int slc_close(struct net_device *dev)
netif_stop_queue(dev);
close_candev(dev);
sl->can.state = CAN_STATE_STOPPED;
+ sl->can.bittiming.bitrate = 0;
sl->rcount = 0;
sl->xleft = 0;
spin_unlock_bh(&sl->lock);
@@ -460,7 +461,9 @@ static int slc_open(struct net_device *dev)
* can.bittiming.bitrate is 0, causing open_candev() to fail.
* So let's set to a fake value.
*/
- sl->can.bittiming.bitrate = -1;
+ if (sl->can.bittiming.bitrate == 0)
+ sl->can.bittiming.bitrate = -1UL;
+
err = open_candev(dev);
if (err) {
netdev_err(dev, "failed to open can device\n");
@@ -558,6 +561,37 @@ static void slc_sync(void)
}
}
+static const u32 slcan_bitrate_const[] = {
+ 10000, 20000, 50000, 100000, 125000,
+ 250000, 500000, 800000, 1000000
+};
+
+static int slc_do_set_bittiming(struct net_device *dev)
+{
+ struct slcan *sl = netdev_priv(dev);
+ unsigned char cmd[SLC_MTU];
+ int s, err;
+
+ for (s = 0; s < ARRAY_SIZE(slcan_bitrate_const); s++) {
+ if (sl->can.bittiming.bitrate == slcan_bitrate_const[s])
+ break;
+ }
+
+ /* The CAN framework has already validate the bitrate value,
+ * so we can avoid to check if `s' has been properly set.
+ */
+
+ snprintf(cmd, sizeof(cmd), "C\rS%d\r", s);
+ err = slcan_transmit_cmd(sl, cmd);
+ if (err) {
+ sl->can.bittiming.bitrate = 0;
+ netdev_err(sl->dev,
+ "failed to send bitrate command 'C\\rS%d\\r'\n", s);
+ }
+
+ return err;
+}
+
/* Find a free SLCAN channel, and link in this `tty' line. */
static struct slcan *slc_alloc(void)
{
@@ -587,6 +621,9 @@ static struct slcan *slc_alloc(void)
/* Initialize channel control data */
sl->magic = SLCAN_MAGIC;
sl->dev = dev;
+ sl->can.bitrate_const = slcan_bitrate_const;
+ sl->can.bitrate_const_cnt = ARRAY_SIZE(slcan_bitrate_const);
+ sl->can.do_set_bittiming = slc_do_set_bittiming;
spin_lock_init(&sl->lock);
INIT_WORK(&sl->tx_work, slcan_transmit);
init_waitqueue_head(&sl->xcmd_wait);
--
2.32.0
