From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH 2/4] Input: introduce ABS_MAX2/CNT2 and friends Date: Wed, 18 Dec 2013 08:36:30 -0800 Message-ID: <20131218163630.GA30922@core.coreip.homeip.net> References: <1387295334-1744-1-git-send-email-dh.herrmann@gmail.com> <1387295334-1744-3-git-send-email-dh.herrmann@gmail.com> <20131218152731.0222ae3b3807601b7756c937@studenti.unina.it> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pa0-f54.google.com ([209.85.220.54]:44804 "EHLO mail-pa0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752692Ab3LRQgf (ORCPT ); Wed, 18 Dec 2013 11:36:35 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: David Herrmann Cc: Antonio Ospite , "open list:HID CORE LAYER" , Jiri Kosina , Benjamin Tissoires , Peter Hutterer , linux-kernel , Input Tools On Wed, Dec 18, 2013 at 03:44:48PM +0100, David Herrmann wrote: > >> > >> /* > >> + * Due to API restrictions the legacy evdev API only supports ABS values up to > >> + * ABS_MAX/CNT. Use the extended *ABS2 ioctls to operate on any ABS values in > >> + * between ABS_MAX and ABS_MAX2. > >> + */ > >> +#define ABS_MAX2 0x3f > >> +#define ABS_CNT2 (ABS_MAX2+1) > >> + > > > > Maybe it's just my English, but when you say "between ABS_MAX and > > ABS_MAX2" it sounds like the old protocol still _must_ be used for > > values <= ABS_MAX. > > > > IIUC this is true "only" for compatibility with older kernels right? > > If a program decides to support only newer kernels it can check the > > protocol version and use only the new ioctls, right? > > > > Maybe you can be more explicit about that in the comment? > > See the comment on "struct input_absinfo2". It describes the API, this > comment just describes the ABS_* values. But if anyone has a better > phrase to use here, I will gladly adjust it. "Use the extended *ABS2 ioctls to access the full range of ABS values supported by the kernel." ? -- Dmitry