netdev - Re: [PATCH] net: lpc_eth: Check clk_prepare

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Date:   Tue, 23 Aug 2016 10:19:58 +0300
From:   Vladimir Zapolskiy <vz@...ia.com>
To:     Fabio Estevam <festevam@...il.com>, davem@...emloft.net
Cc:     netdev@...r.kernel.org, Fabio Estevam <fabio.estevam@....com>
Subject: Re: [PATCH] net: lpc_eth: Check clk_prepare_enable() error

Hi Fabio,

On 23.08.2016 05:01, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam@....com>
> 
> clk_prepare_enable() may fail, so we should better check its return
> value and propagate it in the case of failure.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam@....com>
> ---
>  drivers/net/ethernet/nxp/lpc_eth.c | 29 ++++++++++++++++++++++-------
>  1 file changed, 22 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/net/ethernet/nxp/lpc_eth.c b/drivers/net/ethernet/nxp/lpc_eth.c
> index 4d4ecba..7c796f7 100644
> --- a/drivers/net/ethernet/nxp/lpc_eth.c
> +++ b/drivers/net/ethernet/nxp/lpc_eth.c
> @@ -475,12 +475,19 @@ static void __lpc_get_mac(struct netdata_local *pldat, u8 *mac)
>  	mac[5] = tmp >> 8;
>  }
>  
> -static void __lpc_eth_clock_enable(struct netdata_local *pldat, bool enable)
> +static int __lpc_eth_clock_enable(struct netdata_local *pldat, bool enable)
>  {
> -	if (enable)
> -		clk_prepare_enable(pldat->clk);
> -	else
> +	int ret;
> +
> +	if (enable) {
> +		ret = clk_prepare_enable(pldat->clk);
> +		if (ret)
> +			return ret;
> +	} else {
>  		clk_disable_unprepare(pldat->clk);
> +	}
> +
> +	return 0;
>  }

The change is correct, but let me ask you to replace all instances of
__lpc_eth_clock_enable() with plain clk_prepare_enable() or
clk_disable_unprepare(). It should save one redundant error check also.

--
With best wishes,
Vladimir