can: Unify MTU settings for CAN interfaces

CAN interfaces only support MTU values of 16 (CAN 2.0) and 72 (CAN FD).
Setting the MTU to other values is pointless but it does not really hurt.
With the introduction of the CAN FD support in drivers/net/can a new
function to switch the MTU for CAN FD has been introduced.

This patch makes use of this can_change_mtu() function to check for correct
MTU settings also in legacy CAN (2.0) devices.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
index 1d00b95..f07fa89 100644
--- a/drivers/net/can/at91_can.c
+++ b/drivers/net/can/at91_can.c
@@ -1194,6 +1194,7 @@
 	.ndo_open	= at91_open,
 	.ndo_stop	= at91_close,
 	.ndo_start_xmit	= at91_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static ssize_t at91_sysfs_show_mb0_id(struct device *dev,
diff --git a/drivers/net/can/bfin_can.c b/drivers/net/can/bfin_can.c
index 8d2b89a..543ecce 100644
--- a/drivers/net/can/bfin_can.c
+++ b/drivers/net/can/bfin_can.c
@@ -528,6 +528,7 @@
 	.ndo_open               = bfin_can_open,
 	.ndo_stop               = bfin_can_close,
 	.ndo_start_xmit         = bfin_can_start_xmit,
+	.ndo_change_mtu         = can_change_mtu,
 };
 
 static int bfin_can_probe(struct platform_device *pdev)
diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c
index 951bfed..9c32e9e 100644
--- a/drivers/net/can/c_can/c_can.c
+++ b/drivers/net/can/c_can/c_can.c
@@ -1277,6 +1277,7 @@
 	.ndo_open = c_can_open,
 	.ndo_stop = c_can_close,
 	.ndo_start_xmit = c_can_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 int register_c_can_dev(struct net_device *dev)
diff --git a/drivers/net/can/cc770/cc770.c b/drivers/net/can/cc770/cc770.c
index 0f12abf..d837927 100644
--- a/drivers/net/can/cc770/cc770.c
+++ b/drivers/net/can/cc770/cc770.c
@@ -823,6 +823,7 @@
 	.ndo_open = cc770_open,
 	.ndo_stop = cc770_close,
 	.ndo_start_xmit = cc770_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 int register_cc770dev(struct net_device *dev)
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index c94d698..f425ec2 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -1011,6 +1011,7 @@
 	.ndo_open	= flexcan_open,
 	.ndo_stop	= flexcan_close,
 	.ndo_start_xmit	= flexcan_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static int register_flexcandev(struct net_device *dev)
diff --git a/drivers/net/can/grcan.c b/drivers/net/can/grcan.c
index ab506d6..3fd9fd9 100644
--- a/drivers/net/can/grcan.c
+++ b/drivers/net/can/grcan.c
@@ -1578,6 +1578,7 @@
 	.ndo_open	= grcan_open,
 	.ndo_stop	= grcan_close,
 	.ndo_start_xmit	= grcan_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static int grcan_setup_netdev(struct platform_device *ofdev,
diff --git a/drivers/net/can/janz-ican3.c b/drivers/net/can/janz-ican3.c
index b47df5e..2382c04 100644
--- a/drivers/net/can/janz-ican3.c
+++ b/drivers/net/can/janz-ican3.c
@@ -1594,6 +1594,7 @@
 	.ndo_open	= ican3_open,
 	.ndo_stop	= ican3_stop,
 	.ndo_start_xmit	= ican3_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 /*
diff --git a/drivers/net/can/mcp251x.c b/drivers/net/can/mcp251x.c
index 50aa630..a8b74f8 100644
--- a/drivers/net/can/mcp251x.c
+++ b/drivers/net/can/mcp251x.c
@@ -996,6 +996,7 @@
 	.ndo_open = mcp251x_open,
 	.ndo_stop = mcp251x_stop,
 	.ndo_start_xmit = mcp251x_hard_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static const struct of_device_id mcp251x_of_match[] = {
diff --git a/drivers/net/can/mscan/mscan.c b/drivers/net/can/mscan/mscan.c
index b9f3faa..e0c9be5 100644
--- a/drivers/net/can/mscan/mscan.c
+++ b/drivers/net/can/mscan/mscan.c
@@ -647,9 +647,10 @@
 }
 
 static const struct net_device_ops mscan_netdev_ops = {
-       .ndo_open               = mscan_open,
-       .ndo_stop               = mscan_close,
-       .ndo_start_xmit         = mscan_start_xmit,
+	.ndo_open	= mscan_open,
+	.ndo_stop	= mscan_close,
+	.ndo_start_xmit	= mscan_start_xmit,
+	.ndo_change_mtu	= can_change_mtu,
 };
 
 int register_mscandev(struct net_device *dev, int mscan_clksrc)
diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c
index 6c077eb..6472562 100644
--- a/drivers/net/can/pch_can.c
+++ b/drivers/net/can/pch_can.c
@@ -950,6 +950,7 @@
 	.ndo_open		= pch_can_open,
 	.ndo_stop		= pch_close,
 	.ndo_start_xmit		= pch_xmit,
+	.ndo_change_mtu		= can_change_mtu,
 };
 
 static void pch_can_remove(struct pci_dev *pdev)
diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c
index 55cce47..f31499a 100644
--- a/drivers/net/can/sja1000/sja1000.c
+++ b/drivers/net/can/sja1000/sja1000.c
@@ -642,9 +642,10 @@
 EXPORT_SYMBOL_GPL(free_sja1000dev);
 
 static const struct net_device_ops sja1000_netdev_ops = {
-       .ndo_open               = sja1000_open,
-       .ndo_stop               = sja1000_close,
-       .ndo_start_xmit         = sja1000_start_xmit,
+	.ndo_open	= sja1000_open,
+	.ndo_stop	= sja1000_close,
+	.ndo_start_xmit	= sja1000_start_xmit,
+	.ndo_change_mtu	= can_change_mtu,
 };
 
 int register_sja1000dev(struct net_device *dev)
diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index 3fcdae2..f5b16e0 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -411,10 +411,16 @@
 	slcan_devs[i] = NULL;
 }
 
+static int slcan_change_mtu(struct net_device *dev, int new_mtu)
+{
+	return -EINVAL;
+}
+
 static const struct net_device_ops slc_netdev_ops = {
 	.ndo_open               = slc_open,
 	.ndo_stop               = slc_close,
 	.ndo_start_xmit         = slc_xmit,
+	.ndo_change_mtu         = slcan_change_mtu,
 };
 
 static void slc_setup(struct net_device *dev)
diff --git a/drivers/net/can/softing/softing_main.c b/drivers/net/can/softing/softing_main.c
index 9ea0dcd..3766bd9 100644
--- a/drivers/net/can/softing/softing_main.c
+++ b/drivers/net/can/softing/softing_main.c
@@ -628,6 +628,7 @@
 	.ndo_open = softing_netdev_open,
 	.ndo_stop = softing_netdev_stop,
 	.ndo_start_xmit	= softing_netdev_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static const struct can_bittiming_const softing_btr_const = {
diff --git a/drivers/net/can/ti_hecc.c b/drivers/net/can/ti_hecc.c
index 2c62fe6..258b9c4 100644
--- a/drivers/net/can/ti_hecc.c
+++ b/drivers/net/can/ti_hecc.c
@@ -871,6 +871,7 @@
 	.ndo_open		= ti_hecc_open,
 	.ndo_stop		= ti_hecc_close,
 	.ndo_start_xmit		= ti_hecc_xmit,
+	.ndo_change_mtu		= can_change_mtu,
 };
 
 static int ti_hecc_probe(struct platform_device *pdev)
diff --git a/drivers/net/can/usb/ems_usb.c b/drivers/net/can/usb/ems_usb.c
index 52c42fd..00f2534 100644
--- a/drivers/net/can/usb/ems_usb.c
+++ b/drivers/net/can/usb/ems_usb.c
@@ -883,6 +883,7 @@
 	.ndo_open = ems_usb_open,
 	.ndo_stop = ems_usb_close,
 	.ndo_start_xmit = ems_usb_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static const struct can_bittiming_const ems_usb_bittiming_const = {
diff --git a/drivers/net/can/usb/esd_usb2.c b/drivers/net/can/usb/esd_usb2.c
index 7fbe859..1f8ce91 100644
--- a/drivers/net/can/usb/esd_usb2.c
+++ b/drivers/net/can/usb/esd_usb2.c
@@ -888,6 +888,7 @@
 	.ndo_open = esd_usb2_open,
 	.ndo_stop = esd_usb2_close,
 	.ndo_start_xmit = esd_usb2_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static const struct can_bittiming_const esd_usb2_bittiming_const = {
diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
index e77d110..ea596b5 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c
@@ -1388,6 +1388,7 @@
 	.ndo_open = kvaser_usb_open,
 	.ndo_stop = kvaser_usb_close,
 	.ndo_start_xmit = kvaser_usb_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static const struct can_bittiming_const kvaser_usb_bittiming_const = {
diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_core.c b/drivers/net/can/usb/peak_usb/pcan_usb_core.c
index 0b7a4c3..93e4a55 100644
--- a/drivers/net/can/usb/peak_usb/pcan_usb_core.c
+++ b/drivers/net/can/usb/peak_usb/pcan_usb_core.c
@@ -702,6 +702,7 @@
 	.ndo_open = peak_usb_ndo_open,
 	.ndo_stop = peak_usb_ndo_stop,
 	.ndo_start_xmit = peak_usb_ndo_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 /*
diff --git a/drivers/net/can/usb/usb_8dev.c b/drivers/net/can/usb/usb_8dev.c
index a0fa1fd..cde2634 100644
--- a/drivers/net/can/usb/usb_8dev.c
+++ b/drivers/net/can/usb/usb_8dev.c
@@ -887,6 +887,7 @@
 	.ndo_open = usb_8dev_open,
 	.ndo_stop = usb_8dev_close,
 	.ndo_start_xmit = usb_8dev_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
 };
 
 static const struct can_bittiming_const usb_8dev_bittiming_const = {