Re: [PATCH] ACPI: SBS: Fix present test in acpi_battery_read()
From: Rafael J. Wysocki
Date: Mon Nov 03 2025 - 11:35:48 EST
On Fri, Oct 31, 2025 at 2:03 PM Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
>
> The battery->present variable is a 1 bit bitfield in a u8. This means
> that the "state & (1 << battery->id)" test will only work when
> "battery->id" is zero, otherwise ->present is zero. Fix this by adding
> a !!.
>
> Fixes: db1c291af7ad ("ACPI: SBS: Make SBS reads table-driven.")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> This is a new static checker warning that Harshit and I wrote. It's
> untested.
>
> drivers/acpi/sbs.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/sbs.c b/drivers/acpi/sbs.c
> index a3f95a3fffde..d3edc3bcbf01 100644
> --- a/drivers/acpi/sbs.c
> +++ b/drivers/acpi/sbs.c
> @@ -487,7 +487,7 @@ static int acpi_battery_read(struct acpi_battery *battery)
> if (result)
> return result;
>
> - battery->present = state & (1 << battery->id);
> + battery->present = !!(state & (1 << battery->id));
> if (!battery->present)
> return 0;
>
> --
Applied as 6.18-rc material, thanks!