On Tue, Aug 14, 2012 at 12:53 PM, Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> wrote: > On Tuesday, August 14, 2012 12:32:21 PM Ping Cheng wrote: >> On Sun, Aug 12, 2012 at 2:42 PM, Henrik Rydberg <rydberg@xxxxxxxxxxx> wrote: >> > Many MT devices send a number of keys along with the mt information. >> > This patch makes sure that there is room for them in the packet >> > buffer. >> > >> > Signed-off-by: Henrik Rydberg <rydberg@xxxxxxxxxxx> >> > --- >> > >> > drivers/input/input.c | 10 +++++++--- >> > 1 file changed, 7 insertions(+), 3 deletions(-) >> > >> > diff --git a/drivers/input/input.c b/drivers/input/input.c >> > index 6e90705..8ebf116 100644 >> > --- a/drivers/input/input.c >> > +++ b/drivers/input/input.c >> > @@ -1777,6 +1777,9 @@ static unsigned int >> > input_estimate_events_per_packet(struct input_dev *dev)> >> > if (test_bit(i, dev->relbit)) >> > >> > events++; >> > >> > + /* Make room for KEY and MSC events */ >> > + events += 7; >> >> Hi Henrik, >> >> It is nice to get rid of the redundant pieces and to incorporate >> common functions. Thank you. >> >> I have a question about the code above though. Why do we use 7 >> instead of going through the keys like: >> >> for (i = 0; i < KEY_MAX; i++) >> if (test_bit(i, dev->keybit)) >> events++; > > Because that would result in gross over-estimation for many devices - > my keyboard has 100+ keys but it never sends all of them in one event > frame, not even if I can get a cat to lay on it ;) Thanks for the prompt reply. I thought you were on vacation ;-). So, what device are we talking about here? I thought it is a touch device with a few extra buttons, which are reported as key events. Am I missing something? If it is a touch device, we won't have too many buttons. So, test_bit(i, dev->keybit) won't be true for more than the number of buttons that declared by __set_bit(). I would think we could play a keyboard (this keyboard does not have letters on it ;-) with ten fingers. Ping -- 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
