[PATCH v2 02/11] can: kvaser_usb: Add support for ethtool set_phys_id()

[Jimmy Assarsson <extja@kvaser.com>]

Add support for ethtool set_phys_id(), to physically locate devices by
flashing a LED on the device.

Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
---
Changes in v2:
  - Return inside the switch-case. Suggested by Vincent Mailhol [1]

[1] https://lore.kernel.org/linux-can/20250723083236.9-1-extja@kvaser.com/T/#md10566c624e75c59ec735fed16d5ec4cbdb38430

 .../net/can/usb/kvaser_usb/kvaser_usb_core.c  | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
index daf42080f942..c74875f978c4 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
@@ -753,6 +753,31 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb,
 	return ret;
 }
 
+static int kvaser_usb_set_phys_id(struct net_device *netdev,
+				  enum ethtool_phys_id_state state)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+	const struct kvaser_usb_dev_ops *ops = priv->dev->driver_info->ops;
+
+	switch (state) {
+	case ETHTOOL_ID_ACTIVE:
+		return 3; /* 3 On/Off cycles per second */
+
+	case ETHTOOL_ID_ON:
+		return ops->dev_set_led(priv, KVASER_USB_LED_ON, 1000);
+
+	case ETHTOOL_ID_OFF:
+		return ops->dev_set_led(priv, KVASER_USB_LED_OFF, 1000);
+
+	case ETHTOOL_ID_INACTIVE:
+		/* Turn LED off and restore standard function after 1ms */
+		return ops->dev_set_led(priv, KVASER_USB_LED_OFF, 1);
+
+	default:
+		return -EINVAL;
+	}
+}
+
 static const struct net_device_ops kvaser_usb_netdev_ops = {
 	.ndo_open = kvaser_usb_open,
 	.ndo_stop = kvaser_usb_close,
@@ -763,6 +788,7 @@ static const struct net_device_ops kvaser_usb_netdev_ops = {
 
 static const struct ethtool_ops kvaser_usb_ethtool_ops = {
 	.get_ts_info = can_ethtool_op_get_ts_info_hwts,
+	.set_phys_id = kvaser_usb_set_phys_id,
 };
 
 static void kvaser_usb_remove_interfaces(struct kvaser_usb *dev)
-- 
2.49.0