Re: [PATCH net] net: phy: smsc: add missed clk_disable_unprepare in smsc_phy_probe()

From: Jakub Kicinski
Date: Sat Nov 14 2020 - 14:26:29 EST


On Thu, 12 Nov 2020 19:23:59 +0800 Zhang Changzhong wrote:
> Add the missing clk_disable_unprepare() before return from
> smsc_phy_probe() in the error handling case.
>
> Fixes: bedd8d78aba3 ("net: phy: smsc: LAN8710/20: add phy refclk in support")
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Signed-off-by: Zhang Changzhong <zhangchangzhong@xxxxxxxxxx>
> ---
> drivers/net/phy/smsc.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c
> index ec97669..0fc39ac 100644
> --- a/drivers/net/phy/smsc.c
> +++ b/drivers/net/phy/smsc.c
> @@ -291,8 +291,10 @@ static int smsc_phy_probe(struct phy_device *phydev)
> return ret;
>
> ret = clk_set_rate(priv->refclk, 50 * 1000 * 1000);
> - if (ret)
> + if (ret) {
> + clk_disable_unprepare(priv->refclk);
> return ret;
> + }
>
> return 0;
> }

Applied, thanks!

The code right above looks highly questionable as well:

priv->refclk = clk_get_optional(dev, NULL);
if (IS_ERR(priv->refclk))
dev_err_probe(dev, PTR_ERR(priv->refclk), "Failed to request clock\n");

ret = clk_prepare_enable(priv->refclk);
if (ret)
return ret;

I don't think clk_prepare_enable() will be too happy to see an error
pointer. This should probably be:

priv->refclk = clk_get_optional(dev, NULL);
if (IS_ERR(priv->refclk))
return dev_err_probe(dev, PTR_ERR(priv->refclk),
"Failed to request clock\n");