Message-ID: <65e4c9936f95a23ad56498ac198fd4df35eb8fd6.camel@pengutronix.de>
Subject: Re: [PATCH net-next v4 2/6] net: lan966x: add the basic lan966x
 driver
From:   Philipp Zabel <p.zabel@pengutronix.de>
To:     Horatiu Vultur <horatiu.vultur@microchip.com>, davem@davemloft.net,
        kuba@kernel.org, robh+dt@kernel.org, UNGLinuxDriver@microchip.com,
        linux@armlinux.org.uk, andrew@lunn.ch, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Fri, 26 Nov 2021 11:19:05 +0100
In-Reply-To: <20211126090540.3550913-3-horatiu.vultur@microchip.com>
References: <20211126090540.3550913-1-horatiu.vultur@microchip.com>
         <20211126090540.3550913-3-horatiu.vultur@microchip.com>
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Hi Horatiu,

On Fri, 2021-11-26 at 10:05 +0100, Horatiu Vultur wrote:
[...]
> +static int lan966x_reset_switch(struct lan966x *lan966x)
> +{
> +	struct reset_control *reset;
> +	int val = 0;
> +	int ret;
> +
> +	reset = devm_reset_control_get_shared(lan966x->dev, "switch");
> +	if (IS_ERR(reset))
> +		return dev_err_probe(lan966x->dev, PTR_ERR(reset),
> +				     "Could not obtain switch reset");
> +	reset_control_reset(reset);
> +
> +	reset = devm_reset_control_get_shared(lan966x->dev, "phy");
> +	if (IS_ERR(reset))
> +		return dev_err_probe(lan966x->dev, PTR_ERR(reset),
> +				     "Could not obtain phy reset\n");
> +	reset_control_reset(reset);

In general, please request all resources before activating the hardware.
Here I'd request both reset controls first and only then trigger them.
That way a failure to optain the phy reset won't cause an unnecessary
switch reset.

[...]
> +static int lan966x_remove(struct platform_device *pdev)
> +{
> +	return 0;
> +}

If there is nothing to do here, this function can be removed altogether.

regards
Philipp