Re: [PATCHv1 1/2] net: ethernet: stmmac: dwmac-rk: fix optional clock handling

[Piotr Raczynski <piotr.raczynski@intel.com>]

On Fri, Mar 17, 2023 at 06:42:42PM +0100, Sebastian Reichel wrote:
> Right now any clock errors are printed and otherwise ignored.
> This has multiple disadvantages:
> 
> 1. it prints errors for clocks that do not exist (e.g. rk3588
>    reports errors for "mac_clk_rx", "mac_clk_tx" and "clk_mac_speed")
> 
> 2. it does not handle errors like -EPROBE_DEFER correctly
> 
> This series fixes it by switching to devm_clk_get_optional(),
> so that missing clocks are not considered an error and then
> passing on any other errors using dev_err_probe().
> 

Fixes tag would help here.
Piotr
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
> ---
>  .../net/ethernet/stmicro/stmmac/dwmac-rk.c    | 47 ++++++++++---------
>  1 file changed, 24 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> index 4b8fd11563e4..126812cd17e6 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> @@ -1479,49 +1479,50 @@ static int rk_gmac_clk_init(struct plat_stmmacenet_data *plat)
>  
>  	bsp_priv->clk_enabled = false;
>  
> -	bsp_priv->mac_clk_rx = devm_clk_get(dev, "mac_clk_rx");
> +	bsp_priv->mac_clk_rx = devm_clk_get_optional(dev, "mac_clk_rx");
>  	if (IS_ERR(bsp_priv->mac_clk_rx))
> -		dev_err(dev, "cannot get clock %s\n",
> -			"mac_clk_rx");
> +		return dev_err_probe(dev, PTR_ERR(bsp_priv->mac_clk_rx),
> +				"cannot get clock %s\n", "mac_clk_rx");
>  
> -	bsp_priv->mac_clk_tx = devm_clk_get(dev, "mac_clk_tx");
> +	bsp_priv->mac_clk_tx = devm_clk_get_optional(dev, "mac_clk_tx");
>  	if (IS_ERR(bsp_priv->mac_clk_tx))
> -		dev_err(dev, "cannot get clock %s\n",
> -			"mac_clk_tx");
> +		return dev_err_probe(dev, PTR_ERR(bsp_priv->mac_clk_tx),
> +				"cannot get clock %s\n", "mac_clk_tx");
>  
> -	bsp_priv->aclk_mac = devm_clk_get(dev, "aclk_mac");
> +	bsp_priv->aclk_mac = devm_clk_get_optional(dev, "aclk_mac");
>  	if (IS_ERR(bsp_priv->aclk_mac))
> -		dev_err(dev, "cannot get clock %s\n",
> -			"aclk_mac");
> +		return dev_err_probe(dev, PTR_ERR(bsp_priv->aclk_mac),
> +				"cannot get clock %s\n", "aclk_mac");
>  
> -	bsp_priv->pclk_mac = devm_clk_get(dev, "pclk_mac");
> +	bsp_priv->pclk_mac = devm_clk_get_optional(dev, "pclk_mac");
>  	if (IS_ERR(bsp_priv->pclk_mac))
> -		dev_err(dev, "cannot get clock %s\n",
> -			"pclk_mac");
> +		return dev_err_probe(dev, PTR_ERR(bsp_priv->pclk_mac),
> +				"cannot get clock %s\n", "pclk_mac");
>  
> -	bsp_priv->clk_mac = devm_clk_get(dev, "stmmaceth");
> +	bsp_priv->clk_mac = devm_clk_get_optional(dev, "stmmaceth");
>  	if (IS_ERR(bsp_priv->clk_mac))
> -		dev_err(dev, "cannot get clock %s\n",
> -			"stmmaceth");
> +		return dev_err_probe(dev, PTR_ERR(bsp_priv->clk_mac),
> +				"cannot get clock %s\n", "stmmaceth");
>  
>  	if (bsp_priv->phy_iface == PHY_INTERFACE_MODE_RMII) {
> -		bsp_priv->clk_mac_ref = devm_clk_get(dev, "clk_mac_ref");
> +		bsp_priv->clk_mac_ref = devm_clk_get_optional(dev, "clk_mac_ref");
>  		if (IS_ERR(bsp_priv->clk_mac_ref))
> -			dev_err(dev, "cannot get clock %s\n",
> -				"clk_mac_ref");
> +			return dev_err_probe(dev, PTR_ERR(bsp_priv->clk_mac_ref),
> +					"cannot get clock %s\n", "clk_mac_ref");
>  
>  		if (!bsp_priv->clock_input) {
>  			bsp_priv->clk_mac_refout =
> -				devm_clk_get(dev, "clk_mac_refout");
> +				devm_clk_get_optional(dev, "clk_mac_refout");
>  			if (IS_ERR(bsp_priv->clk_mac_refout))
> -				dev_err(dev, "cannot get clock %s\n",
> -					"clk_mac_refout");
> +				return dev_err_probe(dev, PTR_ERR(bsp_priv->clk_mac_refout),
> +						"cannot get clock %s\n", "clk_mac_refout");
>  		}
>  	}
>  
> -	bsp_priv->clk_mac_speed = devm_clk_get(dev, "clk_mac_speed");
> +	bsp_priv->clk_mac_speed = devm_clk_get_optional(dev, "clk_mac_speed");
>  	if (IS_ERR(bsp_priv->clk_mac_speed))
> -		dev_err(dev, "cannot get clock %s\n", "clk_mac_speed");
> +		return dev_err_probe(dev, PTR_ERR(bsp_priv->clk_mac_speed),
> +				"cannot get clock %s\n", "clk_mac_speed");
>  
>  	if (bsp_priv->clock_input) {
>  		dev_info(dev, "clock input from PHY\n");
> -- 
> 2.39.2
>