Commit 65520a70 authored by Oleksij Rempel's avatar Oleksij Rempel Committed by Jakub Kicinski
Browse files

net: usb: lan78xx: Add error handling to set_rx_max_frame_length and set_mtu 



Improve error handling in `lan78xx_set_rx_max_frame_length` by:
- Checking return values from register read/write operations and
  propagating errors.
- Exiting immediately on failure to ensure proper error reporting.

In `lan78xx_change_mtu`, log errors when changing MTU fails, using `%pe`
for clear error representation.

Signed-off-by: default avatarOleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20241204084142.1152696-9-o.rempel@pengutronix.de


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 77586156

drivers/net/usb/lan78xx.c

+18 −6
Original line number Diff line number Diff line
@@ -2599,27 +2599,36 @@ static int lan78xx_phy_init(struct lan78xx_net *dev) 


static int lan78xx_set_rx_max_frame_length(struct lan78xx_net *dev, int size)

{

	u32 buf;

	bool rxenabled;

	u32 buf;

	int ret;



	lan78xx_read_reg(dev, MAC_RX, &buf);

	ret = lan78xx_read_reg(dev, MAC_RX, &buf);

	if (ret < 0)

		return ret;



	rxenabled = ((buf & MAC_RX_RXEN_) != 0);



	if (rxenabled) {

		buf &= ~MAC_RX_RXEN_;

		lan78xx_write_reg(dev, MAC_RX, buf);

		ret = lan78xx_write_reg(dev, MAC_RX, buf);

		if (ret < 0)

			return ret;

	}



	/* add 4 to size for FCS */

	buf &= ~MAC_RX_MAX_SIZE_MASK_;

	buf |= (((size + 4) << MAC_RX_MAX_SIZE_SHIFT_) & MAC_RX_MAX_SIZE_MASK_);



	lan78xx_write_reg(dev, MAC_RX, buf);

	ret = lan78xx_write_reg(dev, MAC_RX, buf);

	if (ret < 0)

		return ret;



	if (rxenabled) {

		buf |= MAC_RX_RXEN_;

		lan78xx_write_reg(dev, MAC_RX, buf);

		ret = lan78xx_write_reg(dev, MAC_RX, buf);

		if (ret < 0)

			return ret;

	}



	return 0;
@@ -2685,7 +2694,10 @@ static int lan78xx_change_mtu(struct net_device *netdev, int new_mtu) 
		return ret;



	ret = lan78xx_set_rx_max_frame_length(dev, max_frame_len);

	if (!ret)

	if (ret < 0)

		netdev_err(dev->net, "MTU changed to %d from %d failed with %pe\n",

			   new_mtu, netdev->mtu, ERR_PTR(ret));

	else

		WRITE_ONCE(netdev->mtu, new_mtu);



	usb_autopm_put_interface(dev->intf);