can: kvaser_pciefd: Add devlink port support

Register each CAN channel of the device as an devlink physical port.
This makes it easier to get device information for a given network
interface (i.e. can2).

Example output:
$ devlink dev
pci/0000:07:00.0
pci/0000:08:00.0
pci/0000:09:00.0

$ devlink port
pci/0000:07:00.0/0: type eth netdev can0 flavour physical port 0 splittable false
pci/0000:07:00.0/1: type eth netdev can1 flavour physical port 1 splittable false
pci/0000:07:00.0/2: type eth netdev can2 flavour physical port 2 splittable false
pci/0000:07:00.0/3: type eth netdev can3 flavour physical port 3 splittable false
pci/0000:08:00.0/0: type eth netdev can4 flavour physical port 0 splittable false
pci/0000:08:00.0/1: type eth netdev can5 flavour physical port 1 splittable false
pci/0000:09:00.0/0: type eth netdev can6 flavour physical port 0 splittable false
pci/0000:09:00.0/1: type eth netdev can7 flavour physical port 1 splittable false
pci/0000:09:00.0/2: type eth netdev can8 flavour physical port 2 splittable false
pci/0000:09:00.0/3: type eth netdev can9 flavour physical port 3 splittable false

$ devlink port show can2
pci/0000:07:00.0/2: type eth netdev can2 flavour physical port 2 splittable false

$ devlink dev info
pci/0000:07:00.0:
driver kvaser_pciefd
versions:
running:
fw 1.3.75
pci/0000:08:00.0:
driver kvaser_pciefd
versions:
running:
fw 2.4.29
pci/0000:09:00.0:
driver kvaser_pciefd
versions:
running:
fw 1.3.72

$ sudo ethtool -i can2
driver: kvaser_pciefd
version: 6.8.0-40-generic
firmware-version: 1.3.75
expansion-rom-version:
bus-info: 0000:07:00.0
supports-statistics: no
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no

Reviewed-by: Vincent Mailhol <[e-mail]>
Signed-off-by: Jimmy Assarsson <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Marc Kleine-Budde <[e-mail]>

drivers/net/can/kvaser_pciefd/kvaser_pciefd.h

···
 
 struct kvaser_pciefd_can {
 	struct can_priv can;
+	struct devlink_port devlink_port;
 	struct kvaser_pciefd *kv_pcie;
 	void __iomem *reg_base;
 	struct can_berr_counter bec;
···
 };
 
 extern const struct devlink_ops kvaser_pciefd_devlink_ops;
+
+int kvaser_pciefd_devlink_port_register(struct kvaser_pciefd_can *can);
+void kvaser_pciefd_devlink_port_unregister(struct kvaser_pciefd_can *can);
 #endif /* _KVASER_PCIEFD_H */

drivers/net/can/kvaser_pciefd/kvaser_pciefd_core.c

···
 		struct net_device *netdev;
 		struct kvaser_pciefd_can *can;
 		u32 status, tx_nr_packets_max;
+		int ret;
 
 		netdev = alloc_candev(sizeof(struct kvaser_pciefd_can),
 				      roundup_pow_of_two(KVASER_PCIEFD_CAN_TX_MAX_COUNT));
···
 
 		pcie->can[i] = can;
 		kvaser_pciefd_pwm_start(can);
+		ret = kvaser_pciefd_devlink_port_register(can);
+		if (ret) {
+			dev_err(&pcie->pci->dev, "Failed to register devlink port\n");
+			return ret;
+		}
 	}
 
 	return 0;
···
 		if (can) {
 			iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG);
 			kvaser_pciefd_pwm_stop(can);
+			kvaser_pciefd_devlink_port_unregister(can);
 			free_candev(can->can.dev);
 		}
 	}
···
 		unregister_candev(can->can.dev);
 		timer_delete(&can->bec_poll_timer);
 		kvaser_pciefd_pwm_stop(can);
+		kvaser_pciefd_devlink_port_unregister(can);
 	}
 
 	kvaser_pciefd_disable_irq_srcs(pcie);

drivers/net/can/kvaser_pciefd/kvaser_pciefd_devlink.c

···
  */
 #include "kvaser_pciefd.h"
 
+#include <linux/netdevice.h>
 #include <net/devlink.h>
 
 static int kvaser_pciefd_devlink_info_get(struct devlink *devlink,
···
 const struct devlink_ops kvaser_pciefd_devlink_ops = {
 	.info_get = kvaser_pciefd_devlink_info_get,
 };
+
+int kvaser_pciefd_devlink_port_register(struct kvaser_pciefd_can *can)
+{
+	int ret;
+	struct devlink_port_attrs attrs = {
+		.flavour = DEVLINK_PORT_FLAVOUR_PHYSICAL,
+		.phys.port_number = can->can.dev->dev_port,
+	};
+	devlink_port_attrs_set(&can->devlink_port, &attrs);
+
+	ret = devlink_port_register(priv_to_devlink(can->kv_pcie),
+				    &can->devlink_port, can->can.dev->dev_port);
+	if (ret)
+		return ret;
+
+	SET_NETDEV_DEVLINK_PORT(can->can.dev, &can->devlink_port);
+
+	return 0;
+}
+
+void kvaser_pciefd_devlink_port_unregister(struct kvaser_pciefd_can *can)
+{
+	devlink_port_unregister(&can->devlink_port);
+}