Re: [PATCH 2/9] input: goodix: fix variable length array warning

Antonio Ospite
2015-05-28T15:58:25Z

On Thu, 28 May 2015 15:47:38 +0300
Irina Tirdea <irina.tirdea@intel.com> wrote:

> Fix sparse warning:
> drivers/input/touchscreen/goodix.c:182:26: warning:
> Variable length array is used.
>
> Replace the variable length array with fixed length.
>
> Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
> ---
> drivers/input/touchscreen/goodix.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
> index c2e785c..dac1b3c 100644
> --- a/drivers/input/touchscreen/goodix.c
> +++ b/drivers/input/touchscreen/goodix.c
> @@ -147,7 +147,7 @@ static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
> */
> static void goodix_process_events(struct goodix_ts_data *ts)
> {
> - u8 point_data[1 + GOODIX_CONTACT_SIZE * ts->max_touch_num];
> + u8 point_data[1 + GOODIX_CONTACT_SIZE * GOODIX_MAX_CONTACTS];

Hi,

this fixes the warning from sparse, but also changes the semantics of
the code: ts->max_touch_num is less that GOODIX_MAX_CONTACTS for 5
touches devices and in this case we'll end up using more memory than is
necessary.

Thanks,
Antonio

> int touch_num;
> int i;
>
> --
> 1.9.1
>
> --
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--
Antonio Ospite
http://ao2.it

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