can: esd_usb: Rework display of error messages

- esd_usb_open(): Get rid of duplicate "couldn't start device: %d\n"
  message already printed from esd_usb_start().
- Fix duplicate printout of network device name when network device
  is registered. Add an unregister message for the network device
  as counterpart to the register message.
- Add the printout of error codes together with the error messages
  in esd_usb_close() and some in esd_usb_probe(). The additional error
  codes should lead to a better understanding what is really going
  wrong.
- Convert all occurrences of error status prints to use "ERR_PTR(err)"
  instead of printing the decimal value of "err".
- Rename retval to err in esd_usb_read_bulk_callback() to make the
  naming of error status variables consistent with all other functions.

Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
Link: https://patch.msgid.link/20250821143422.3567029-5-stefan.maetje@esd.eu
[mkl: minor change patch description to imperative language]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
index 27a3818885c2ca7451e9ce959b06e6e15e70a4a6..14b5df4d55430d22ba7575239127a24107c36e70 100644 (file)
--- a/drivers/net/can/usb/esd_usb.c
+++ b/drivers/net/can/usb/esd_usb.c
@@ -9,6 +9,7 @@
 #include <linux/can.h>
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
+#include <linux/err.h>
 #include <linux/ethtool.h>
 #include <linux/module.h>
 #include <linux/netdevice.h>
@@ -480,7 +481,7 @@ static void esd_usb_tx_done_msg(struct esd_usb_net_priv *priv,
 static void esd_usb_read_bulk_callback(struct urb *urb)
 {
        struct esd_usb *dev = urb->context;
-       int retval;
+       int err;
        int pos = 0;
        int i;
 
@@ -496,7 +497,7 @@ static void esd_usb_read_bulk_callback(struct urb *urb)
 
        default:
                dev_info(dev->udev->dev.parent,
-                        "Rx URB aborted (%d)\n", urb->status);
+                        "Rx URB aborted (%pe)\n", ERR_PTR(urb->status));
                goto resubmit_urb;
        }
 
@@ -539,15 +540,15 @@ resubmit_urb:
                          urb->transfer_buffer, ESD_USB_RX_BUFFER_SIZE,
                          esd_usb_read_bulk_callback, dev);
 
-       retval = usb_submit_urb(urb, GFP_ATOMIC);
-       if (retval == -ENODEV) {
+       err = usb_submit_urb(urb, GFP_ATOMIC);
+       if (err == -ENODEV) {
                for (i = 0; i < dev->net_count; i++) {
                        if (dev->nets[i])
                                netif_device_detach(dev->nets[i]->netdev);
                }
-       } else if (retval) {
+       } else if (err) {
                dev_err(dev->udev->dev.parent,
-                       "failed resubmitting read bulk urb: %d\n", retval);
+                       "failed resubmitting read bulk urb: %pe\n", ERR_PTR(err));
        }
 }
 
@@ -572,7 +573,7 @@ static void esd_usb_write_bulk_callback(struct urb *urb)
                return;
 
        if (urb->status)
-               netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
+               netdev_info(netdev, "Tx URB aborted (%pe)\n", ERR_PTR(urb->status));
 
        netif_trans_update(netdev);
 }
@@ -758,7 +759,7 @@ out:
        if (err == -ENODEV)
                netif_device_detach(netdev);
        if (err)
-               netdev_err(netdev, "couldn't start device: %d\n", err);
+               netdev_err(netdev, "couldn't start device: %pe\n", ERR_PTR(err));
 
        kfree(msg);
        return err;
@@ -800,7 +801,6 @@ static int esd_usb_open(struct net_device *netdev)
        /* finally start device */
        err = esd_usb_start(priv);
        if (err) {
-               netdev_warn(netdev, "couldn't start device: %d\n", err);
                close_candev(netdev);
                return err;
        }
@@ -923,7 +923,7 @@ static netdev_tx_t esd_usb_start_xmit(struct sk_buff *skb,
                if (err == -ENODEV)
                        netif_device_detach(netdev);
                else
-                       netdev_warn(netdev, "failed tx_urb %d\n", err);
+                       netdev_warn(netdev, "failed tx_urb %pe\n", ERR_PTR(err));
 
                goto releasebuf;
        }
@@ -951,6 +951,7 @@ static int esd_usb_close(struct net_device *netdev)
 {
        struct esd_usb_net_priv *priv = netdev_priv(netdev);
        union esd_usb_msg *msg;
+       int err;
        int i;
 
        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
@@ -964,8 +965,9 @@ static int esd_usb_close(struct net_device *netdev)
        msg->filter.option = ESD_USB_ID_ENABLE; /* start with segment 0 */
        for (i = 0; i <= ESD_USB_MAX_ID_SEGMENT; i++)
                msg->filter.mask[i] = 0;
-       if (esd_usb_send_msg(priv->usb, msg) < 0)
-               netdev_err(netdev, "sending idadd message failed\n");
+       err = esd_usb_send_msg(priv->usb, msg);
+       if (err < 0)
+               netdev_err(netdev, "sending idadd message failed: %pe\n", ERR_PTR(err));
 
        /* set CAN controller to reset mode */
        msg->hdr.len = sizeof(struct esd_usb_set_baudrate_msg) / sizeof(u32); /* # of 32bit words */
@@ -973,8 +975,9 @@ static int esd_usb_close(struct net_device *netdev)
        msg->setbaud.net = priv->index;
        msg->setbaud.rsvd = 0;
        msg->setbaud.baud = cpu_to_le32(ESD_USB_NO_BAUDRATE);
-       if (esd_usb_send_msg(priv->usb, msg) < 0)
-               netdev_err(netdev, "sending setbaud message failed\n");
+       err = esd_usb_send_msg(priv->usb, msg);
+       if (err < 0)
+               netdev_err(netdev, "sending setbaud message failed: %pe\n", ERR_PTR(err));
 
        priv->can.state = CAN_STATE_STOPPED;
 
@@ -1251,14 +1254,14 @@ static int esd_usb_probe_one_net(struct usb_interface *intf, int index)
 
        err = register_candev(netdev);
        if (err) {
-               dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
+               dev_err(&intf->dev, "couldn't register CAN device: %pe\n", ERR_PTR(err));
                free_candev(netdev);
                err = -ENOMEM;
                goto done;
        }
 
        dev->nets[index] = priv;
-       netdev_info(netdev, "device %s registered\n", netdev->name);
+       netdev_info(netdev, "registered\n");
 
 done:
        return err;
@@ -1357,6 +1360,7 @@ static void esd_usb_disconnect(struct usb_interface *intf)
                for (i = 0; i < dev->net_count; i++) {
                        if (dev->nets[i]) {
                                netdev = dev->nets[i]->netdev;
+                               netdev_info(netdev, "unregister\n");
                                unregister_netdev(netdev);
                                free_candev(netdev);
                        }