[PATCH] net: lwip: introduce net_lwip_eth_stop() function

[David Lechner]

On 5/11/26 1:08 PM, Simon Glass wrote:
> Hi David,
> 
> On 2026-05-09T17:36:26, David Lechner <dlechner at baylibre.com> wrote:
>> net: lwip: introduce net_lwip_eth_stop() function
>>
>> Add a introduce net_lwip_eth_stop() function and use that to stop the
>> network interface after each command that uses the network.
>>
>> This makes the behavior the same as the legacy net code and avoids
>> potential issues with the network interface being left in an active
>> state after a command finishes.
>>
>> Signed-off-by: David Lechner <dlechner at baylibre.com>
>>
>> cmd/lwip/ping.c     | 10 ++++++++--
>>  cmd/lwip/sntp.c     | 10 ++++++++--
>>  include/net-lwip.h  |  1 +
>>  net/lwip/dhcp.c     | 15 +++++++++++----
>>  net/lwip/dns.c      |  6 +++++-
>>  net/lwip/net-lwip.c |  6 +++++-
>>  net/lwip/nfs.c      |  4 ++++
>>  net/lwip/tftp.c     |  4 ++++
>>  net/lwip/wget.c     | 34 ++++++++++++++++++++++------------
>>  9 files changed, 68 insertions(+), 22 deletions(-)
> 
>> diff --git a/net/lwip/wget.c b/net/lwip/wget.c
>> @@ -302,6 +302,7 @@ int wget_do_request(ulong dst_addr, char *uri)
>>       struct udevice *udev;
>>       struct netif *netif;
>>       struct wget_ctx ctx;
>> +     int ret = CMD_RET_USAGE;
>>       char *path;
>>       bool is_https;
> 
> Initialising ret to CMD_RET_USAGE changes error paths:
> 
>    netif = net_lwip_new_netif(udev);
>    if (!netif)
>         goto out_stop;          /* ret is still CMD_RET_USAGE */
> 
>    if (!tls_allocator.arg) {
>         log_err(...);
>         goto out_remove_netif;  /* ret is still CMD_RET_USAGE */
>    }
> 
> The fall-through after 'Certificate verification failed' also lands on
> out_remove_netif with ret unchanged. These paths previously returned
> -1; now they return CMD_RET_USAGE (1), so the command framework prints
> usage for a network/TLS failure.

The code I am looking at says:

enum command_ret_t {
	CMD_RET_SUCCESS,	/* 0 = Success */
	CMD_RET_FAILURE,	/* 1 = Failure */
	CMD_RET_USAGE = -1,	/* Failure, please report 'usage' error */
}; 

So I don't think these changed. CMD_RET_USAGE is -1.

Happy to init it -1 though as you suggest if the name doesn't make
sense here. That is might be why it was -1 before instead of using
the macro anyway.

> 
> wget_do_request() isn't a command handler either, so CMD_RET_USAGE is
> doubly out of place. Please initialise ret to -1 and set ret =
> CMD_RET_FAILURE explicitly only in the paths that previously returned
> that.
> 
> It might make sense to split this up function (perhaps in a prior
> patch) to try to make the error handling easier?
> 
Sure. Is there a common naming pattern for that in U-Boot. I would
call the inner function __wget_do_request(). But I know opinions on
such things can vary widely. :-)