On Wed, 3 Jun 2015 10:26:47 +0000 "Tirdea, Irina" <irina.tirdea@xxxxxxxxx> wrote: > > -----Original Message----- > > From: Antonio Ospite [mailto:ao2@xxxxxx] > > Sent: 28 May, 2015 18:58 > > To: Tirdea, Irina > > Cc: Dmitry Torokhov; Bastien Nocera; linux-input@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH 2/9] input: goodix: fix variable length array warning > > > > On Thu, 28 May 2015 15:47:38 +0300 > > Irina Tirdea <irina.tirdea@xxxxxxxxx> 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@xxxxxxxxx> > > > --- > > > 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, > > > > Hi Antonio, > > > 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. > > > > I wasn't sure if it is better to save the 5 bytes or fix the warning, > so I sent this to get some more input. > Thanks for the feedback, I will drop this patch. > Use kmalloc() or, alternatively, add at least a comment telling why you think that sacrificing a few bytes —only for some devices— has advantages over dynamic allocation. I am not necessarily against the static allocation change, I was just pointing out the issue. Thanks, Antonio -- Antonio Ospite http://ao2.it A: Because it messes up the order in which people normally read text. See http://en.wikipedia.org/wiki/Posting_style Q: Why is top-posting such a bad thing? -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
