Re: [PATCH v27 05/11] soc: mediatek: refine code to use mtk_mmsys_update_bits API

From: Nícolas F. R. A. Prado
Date: Thu Nov 03 2022 - 16:32:50 EST


On Thu, Nov 03, 2022 at 11:25:06AM +0800, Nancy.Lin wrote:
[..]
> --- a/drivers/soc/mediatek/mtk-mmsys.c
> +++ b/drivers/soc/mediatek/mtk-mmsys.c
[..]
> +static void mtk_mmsys_update_bits(struct mtk_mmsys *mmsys, u32 offset, u32 mask, u32 val)
> +{
> + u32 tmp;
> +
> + tmp = readl_relaxed(mmsys->regs + offset);
> + tmp = (tmp & ~mask) | val;

You should mask the value before writing to prevent bad values from overwriting
bits outside the mask.

tmp = (tmp & ~mask) | (val & mask);

With that,

Reviewed-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>

Thanks,
Nícolas