Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755129Ab2HOAyM (ORCPT ); Tue, 14 Aug 2012 20:54:12 -0400 Received: from mail-lpp01m010-f46.google.com ([209.85.215.46]:57171 "EHLO mail-lpp01m010-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751044Ab2HOAyK (ORCPT ); Tue, 14 Aug 2012 20:54:10 -0400 MIME-Version: 1.0 In-Reply-To: <20120814211200.GA32249@core.coreip.homeip.net> References: <1344807757-2217-1-git-send-email-rydberg@euromail.se> <1344807757-2217-3-git-send-email-rydberg@euromail.se> <2226930.JeU38gc4Sp@dtor-d630.eng.vmware.com> <20120814211200.GA32249@core.coreip.homeip.net> Date: Tue, 14 Aug 2012 17:54:08 -0700 Message-ID: Subject: Re: [PATCH 02/19] Input: Improve the events-per-packet estimate From: Ping Cheng To: Dmitry Torokhov Cc: Henrik Rydberg , Jiri Kosina , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2041 Lines: 49 On Tue, Aug 14, 2012 at 2:12 PM, Dmitry Torokhov wrote: > >> On Sun, Aug 12, 2012 at 2:42 PM, Henrik Rydberg 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. >> >> 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? > > I was talking about a bog-standard computer keyboard here. > >> >> 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(). > > input_estimate_events_per_packet() is a generic routine that is used for > all devices, not only [multi]touch. I understand you are talking about standard keyboard. And I know this routine is for all devices. However, from the commit comments, the patch is to address an MT issue. If it is not just for MT, we need either to make it clear in the comments or to verify the type of the device in the code. >> I would think we could play a keyboard (this keyboard does not have >> letters on it ;-) with ten fingers. > > But even that keyboard would have more than 10 keys, right? So even > though max_events should be 10 + 10 + 1 (10 keys, 10 msc, syn) your loop > would produce what 88 + 88 + 1 for full size music keyboard? No, I was not talking about implementing full music keyboard functions in the kernel. My point was: why do we take 7 instead of 10, or another number? In fact, 7 works for me as long as we explain the rationale behind the decision. I do not have a device that needs to post 10 button events simultaneously, yet ;-). Ping -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/