Re: [PATCH net-next v3 3/3] net: dsa: rzn1-a5psw: add vlan support

[Vladimir Oltean]

On Wed, Feb 08, 2023 at 05:17:49PM +0100, Clément Léger wrote:
> +static void a5psw_port_vlan_tagged_cfg(struct a5psw *a5psw, int vlan_res_id,
> +				       int port, bool set)
> +{
> +	u32 mask = A5PSW_VLAN_RES_WR_PORTMASK | A5PSW_VLAN_RES_RD_TAGMASK |
> +		   BIT(port);
> +	u32 vlan_res_off = A5PSW_VLAN_RES(vlan_res_id);
> +	u32 val = A5PSW_VLAN_RES_WR_TAGMASK, reg;
> +
> +	if (set)
> +		val |= BIT(port);
> +
> +	/* Toggle tag mask read */
> +	a5psw_reg_writel(a5psw, vlan_res_off, A5PSW_VLAN_RES_RD_TAGMASK);
> +	reg = a5psw_reg_readl(a5psw, vlan_res_off);
> +	a5psw_reg_writel(a5psw, vlan_res_off, A5PSW_VLAN_RES_RD_TAGMASK);

Is it intentional that this register is written twice?

> +
> +	reg &= ~mask;
> +	reg |= val;
> +	a5psw_reg_writel(a5psw, vlan_res_off, reg);
> +}