[PATCH] cpufreq: mediatek: fix device leak on probe failure

[Chen-Yu Tsai]

On Tue, Sep 9, 2025 at 5:40 PM Johan Hovold <johan at kernel.org> wrote:
>
> Make sure to drop the reference to the cci device taken by
> of_find_device_by_node() on probe failure (e.g. probe deferral).
>
> Fixes: 0daa47325bae ("cpufreq: mediatek: Link CCI device to CPU")
> Cc: Jia-Wei Chang <jia-wei.chang at mediatek.com>
> Cc: Rex-BC Chen <rex-bc.chen at mediatek.com>
> Signed-off-by: Johan Hovold <johan at kernel.org>
> ---
>  drivers/cpufreq/mediatek-cpufreq.c | 14 +++++++++++---
>  1 file changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
> index f3f02c4b6888..21537a05785d 100644
> --- a/drivers/cpufreq/mediatek-cpufreq.c
> +++ b/drivers/cpufreq/mediatek-cpufreq.c
> @@ -404,9 +404,11 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
>         }
>
>         info->cpu_clk = clk_get(cpu_dev, "cpu");
> -       if (IS_ERR(info->cpu_clk))
> -               return dev_err_probe(cpu_dev, PTR_ERR(info->cpu_clk),
> -                                    "cpu%d: failed to get cpu clk\n", cpu);
> +       if (IS_ERR(info->cpu_clk)) {
> +               ret = PTR_ERR(info->cpu_clk);
> +               dev_err_probe(cpu_dev, ret, "cpu%d: failed to get cpu clk\n", cpu);
> +               goto out_put_cci_dev;
> +       }
>
>         info->inter_clk = clk_get(cpu_dev, "intermediate");
>         if (IS_ERR(info->inter_clk)) {
> @@ -552,6 +554,10 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
>  out_free_mux_clock:
>         clk_put(info->cpu_clk);
>
> +out_put_cci_dev:
> +       if (info->soc_data->ccifreq_supported)
> +               put_device(info->cci_dev);

put_device() has a check for NULL, so the if isn't really needed.

Either way,

Reviewed-by: Chen-Yu Tsai <wenst at chromium.org>

> +
>         return ret;
>  }
>
> @@ -569,6 +575,8 @@ static void mtk_cpu_dvfs_info_release(struct mtk_cpu_dvfs_info *info)
>         clk_put(info->inter_clk);
>         dev_pm_opp_of_cpumask_remove_table(&info->cpus);
>         dev_pm_opp_unregister_notifier(info->cpu_dev, &info->opp_nb);
> +       if (info->soc_data->ccifreq_supported)
> +               put_device(info->cci_dev);
>  }
>
>  static int mtk_cpufreq_init(struct cpufreq_policy *policy)
> --
> 2.49.1
>
>