Re: [PATCH v2] PM: EM: Fix wrong return value in mtk_cpufreq_get_cpu_power()

[Lukasz Luba <lukasz.luba@arm.com>]

On 11/4/24 11:36, Jinjie Ruan wrote:
> mtk_cpufreq_get_cpu_power() return 0 if the policy is NULL. Then in
> em_create_perf_table(), the later zero check for power is not invalid
> as power is uninitialized. As Lukasz suggested, it must return -EINVAL when
> the 'policy' is not found. So return -EINVAL to fix it.
> 
> Cc: stable@vger.kernel.org
> Fixes: 4855e26bcf4d ("cpufreq: mediatek-hw: Add support for CPUFREQ HW")
> Suggested-by: Lukasz Luba <lukasz.luba@arm.com>
> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
> ---
> v2:
> - Fix the driver instead of em_create_perf_table() as suggested.
> - Update the commit message.
> - Add Suggested-by.
> ---
>   drivers/cpufreq/mediatek-cpufreq-hw.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/cpufreq/mediatek-cpufreq-hw.c b/drivers/cpufreq/mediatek-cpufreq-hw.c
> index 8925e096d5b9..aeb5e6304542 100644
> --- a/drivers/cpufreq/mediatek-cpufreq-hw.c
> +++ b/drivers/cpufreq/mediatek-cpufreq-hw.c
> @@ -62,7 +62,7 @@ mtk_cpufreq_get_cpu_power(struct device *cpu_dev, unsigned long *uW,
>   
>   	policy = cpufreq_cpu_get_raw(cpu_dev->id);
>   	if (!policy)
> -		return 0;
> +		return -EINVAL;
>   
>   	data = policy->driver_data;
>   

LGTM,

Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>