Subject: Re: [net-next PATCH 5/5 v2] net: dsa: rtl8366: Use top VLANs for default

From: Andrew Lunn <[email-masked]>
Date: Thu, 18 Jun 2020 03:42:46 +0200

On Wed, Jun 17, 2020 at 10:31:32AM +0200, Linus Walleij wrote:
> The RTL8366 DSA switches will not work unless we set
> up a default VLAN for each port. We are currently using
> e.g. VLAN 1..6 for a 5-port switch as default VLANs.
> 
> This is not very helpful for users, move it to allocate
> the top VLANs for default instead, for example on
> RTL8366RB there are 16 VLANs so instead of using
> VLAN 1..6 as default use VLAN 10..15 so VLAN 1
> thru VLAN 9 is available for users.
> 
> Cc: DENG Qingfang <[email-masked]>
> Cc: Mauri Sandberg <[email-masked]>
> Signed-off-by: Linus Walleij <[email-masked]>
> ---
> ChangeLog v1->v2:
> - Rebase on v5.8-rc1.
> ---
>  drivers/net/dsa/rtl8366.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/dsa/rtl8366.c b/drivers/net/dsa/rtl8366.c
> index 7f0691a6da13..4e7562b41598 100644
> --- a/drivers/net/dsa/rtl8366.c
> +++ b/drivers/net/dsa/rtl8366.c
> @@ -260,8 +260,8 @@ static int rtl8366_set_default_vlan_and_pvid(struct realtek_smi *smi,
>  	u16 vid;
>  	int ret;
>  
> -	/* This is the reserved default VLAN for this port */
> -	vid = port + 1;
> +	/* Use the top VLANs for per-port default VLAN */
> +	vid = smi->num_vlan_mc - smi->num_ports + port;

Hi Linus

I've not looked at the whole driver much, but i'm surprised the change
is this small. Is there any checks when user space ask for a VLAN to
be added to a port to see if it is already in use an return -EBUSY or
-EINVAL or something?

	Andrew