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Date:   Sun, 30 Sep 2018 22:16:42 +0200
From:   Pavel Machek <pavel@ucw.cz>
To:     Andreas Kemnade <andreas@kemnade.info>
Cc:     sre@kernel.org, linux-pm@vger.kernel.org,
        linux-omap@vger.kernel.org,
        Discussions about the Letux Kernel 
        <letux-kernel@openphoenux.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND] twl4030_charger: fix charging current
 out-of-bounds
Message-ID: <20180930201642.GC23554@amd>
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On Mon 2018-09-17 07:20:35, Andreas Kemnade wrote:
> the charging current uses unsigned int variables, if we step back
> if the current is still low, we would run into negative which
> means setting the target to a huge value.
> Better add checks here.

Do you expect this to happen in practice? Too high current while
charging seems bad, right?

Cc: stable?
								Pavel

> Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
> ---
>  drivers/power/supply/twl4030_charger.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>=20
> diff --git a/drivers/power/supply/twl4030_charger.c b/drivers/power/suppl=
y/twl4030_charger.c
> index b72838663872..c954b7234393 100644
> --- a/drivers/power/supply/twl4030_charger.c
> +++ b/drivers/power/supply/twl4030_charger.c
> @@ -421,7 +421,8 @@ static void twl4030_current_worker(struct work_struct=
 *data)
> =20
>  	if (v < USB_MIN_VOLT) {
>  		/* Back up and stop adjusting. */
> -		bci->usb_cur -=3D USB_CUR_STEP;
> +		if (bci->usb_cur >=3D USB_CUR_STEP)
> +			bci->usb_cur -=3D USB_CUR_STEP;
>  		bci->usb_cur_target =3D bci->usb_cur;
>  	} else if (bci->usb_cur >=3D bci->usb_cur_target ||
>  		   bci->usb_cur + USB_CUR_STEP > USB_MAX_CURRENT) {

--=20
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