From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eduard Hasenleithner Subject: Re: [PATCH v2] Wacom Intuos4 LED and OLED support Date: Tue, 5 Apr 2011 21:28:52 +0200 Message-ID: References: <1301817429-12782-1-git-send-email-eduard@hasenleithner.at> <20110405182808.GB13086@core.coreip.homeip.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: Received: from mail-iy0-f174.google.com ([209.85.210.174]:60315 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753739Ab1DET2w (ORCPT ); Tue, 5 Apr 2011 15:28:52 -0400 Received: by iyb14 with SMTP id 14so688733iyb.19 for ; Tue, 05 Apr 2011 12:28:52 -0700 (PDT) In-Reply-To: <20110405182808.GB13086@core.coreip.homeip.net> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Dmitry Torokhov Cc: linux-input@vger.kernel.org Hi 2011/4/5 Dmitry Torokhov : > On Tue, Apr 05, 2011 at 08:12:07PM +0200, Eduard Hasenleithner wrote: >> I have been encouraged by Ping Cheng to submit the OLED matrix display >> patch for the Intuos4 to the linux-input mailing list. In absence of >> any comment by you on this issue, I'm a bit lost. Could you give >> something like a quick ACK (e.g. you will have a look into it later, >> when you have time) or NACK (e.g. no way for inclusion, needs major >> change, ...). > > Sorry, just a bit swamped at the moment (unfortunately happens to be > quite often ;( ), that is why not responding... If you like, I can come back in a month or so for discussion. Or you write me an email when you are less stressed (you being a maintainer, this is probably just wishful thinking). > The main issue for me is adding a new device-specific interface. Are > there any other suitable ways to provide access to the functionality? > Something like auxdisplay? I had the impression that using the existing RAW USB-device IOCTL mechanism would not be considered an additional interface. There is no change in the event- or any other subsystem, just in the wacom driver. And, as a bonus, using sysfs the RAW USB Device belonging to the event device can be located in a straight forward way. Since the wacom driver "grabs" the USB device and the OLED part of the Intuos4 is not a separate USB device, the display control has to be performed in any case in the wacom (input) driver. A "auxdisplay" implementation would then have to be done also there. Wrt auxdisplay: a quick look at the driver reveals that it exposes a (generic?) framebuffer device. If you say: "This is the way to go", I'll try it. It is just that I fear that some X-Server might automatically use it as display, which is not exactly my intention ;) Furthermore, there are four LEDs (only one can be lit at a time) on the device, and three different luminace settings, which would probably need some IOCTL anyway. And due to the higher complexity, implementing a (simulated) framebuffer device provides more possibilities for bugs. Thanks, Eduard