Re: [net-next PATCH 05/19] net: dsa: qca8k: move read switch id function in qca8k_setup

[Vladimir Oltean]

On Wed, Nov 17, 2021 at 10:04:37PM +0100, Ansuel Smith wrote:
> Move read_switch_id function in qca8k_setup in preparation for regmap
> conversion. Sw probe should NOT contain function that depends on reading
> from switch regs.

It shouldn't? Why? We have plenty of switch drivers that use regmap in
the probe function.

> 
> Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
> ---
>  drivers/net/dsa/qca8k.c | 71 ++++++++++++++++++++---------------------
>  1 file changed, 35 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
> index 19331edf1fd4..be98d11b17ec 100644
> --- a/drivers/net/dsa/qca8k.c
> +++ b/drivers/net/dsa/qca8k.c
> @@ -1073,6 +1073,36 @@ qca8k_parse_port_config(struct qca8k_priv *priv)
>  	return 0;
>  }
>  
> +static int qca8k_read_switch_id(struct qca8k_priv *priv)
> +{
> +	const struct qca8k_match_data *data;
> +	u32 val;
> +	u8 id;
> +	int ret;
> +
> +	/* get the switches ID from the compatible */
> +	data = of_device_get_match_data(priv->dev);
> +	if (!data)
> +		return -ENODEV;
> +
> +	ret = qca8k_read(priv, QCA8K_REG_MASK_CTRL, &val);
> +	if (ret < 0)
> +		return -ENODEV;
> +
> +	id = QCA8K_MASK_CTRL_DEVICE_ID(val);
> +	if (id != data->id) {
> +		dev_err(priv->dev, "Switch id detected %x but expected %x", id, data->id);
> +		return -ENODEV;
> +	}
> +
> +	priv->switch_id = id;
> +
> +	/* Save revision to communicate to the internal PHY driver */
> +	priv->switch_revision = QCA8K_MASK_CTRL_REV_ID(val);
> +
> +	return 0;
> +}
> +
>  static int
>  qca8k_setup(struct dsa_switch *ds)
>  {
> @@ -1080,6 +1110,11 @@ qca8k_setup(struct dsa_switch *ds)
>  	int cpu_port, ret, i;
>  	u32 mask;
>  
> +	/* Check the detected switch id */
> +	ret = qca8k_read_switch_id(priv);
> +	if (ret)
> +		return ret;
> +
>  	cpu_port = qca8k_find_cpu_port(ds);
>  	if (cpu_port < 0) {
>  		dev_err(priv->dev, "No cpu port configured in both cpu port0 and port6");
> @@ -2023,41 +2058,10 @@ static const struct dsa_switch_ops qca8k_switch_ops = {
>  	.get_phy_flags		= qca8k_get_phy_flags,
>  };
>  
> -static int qca8k_read_switch_id(struct qca8k_priv *priv)
> -{
> -	const struct qca8k_match_data *data;
> -	u32 val;
> -	u8 id;
> -	int ret;
> -
> -	/* get the switches ID from the compatible */
> -	data = of_device_get_match_data(priv->dev);
> -	if (!data)
> -		return -ENODEV;
> -
> -	ret = qca8k_read(priv, QCA8K_REG_MASK_CTRL, &val);
> -	if (ret < 0)
> -		return -ENODEV;
> -
> -	id = QCA8K_MASK_CTRL_DEVICE_ID(val);
> -	if (id != data->id) {
> -		dev_err(priv->dev, "Switch id detected %x but expected %x", id, data->id);
> -		return -ENODEV;
> -	}
> -
> -	priv->switch_id = id;
> -
> -	/* Save revision to communicate to the internal PHY driver */
> -	priv->switch_revision = QCA8K_MASK_CTRL_REV_ID(val);
> -
> -	return 0;
> -}
> -
>  static int
>  qca8k_sw_probe(struct mdio_device *mdiodev)
>  {
>  	struct qca8k_priv *priv;
> -	int ret;
>  
>  	/* allocate the private data struct so that we can probe the switches
>  	 * ID register
> @@ -2083,11 +2087,6 @@ qca8k_sw_probe(struct mdio_device *mdiodev)
>  		gpiod_set_value_cansleep(priv->reset_gpio, 0);
>  	}
>  
> -	/* Check the detected switch id */
> -	ret = qca8k_read_switch_id(priv);
> -	if (ret)
> -		return ret;
> -
>  	priv->ds = devm_kzalloc(&mdiodev->dev, sizeof(*priv->ds), GFP_KERNEL);
>  	if (!priv->ds)
>  		return -ENOMEM;
> -- 
> 2.32.0
>