From mboxrd@z Thu Jan 1 00:00:00 1970 From: Manuel Reimer Subject: Re: How to get the kernel to emulate force feedback events? Date: Sun, 21 Feb 2016 15:07:16 +0100 Message-ID: <56C9C494.6070500@m-reimer.de> References: <56C8BE6D.7050409@m-reimer.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.mailbox.org ([80.241.60.212]:52986 "EHLO mx1.mailbox.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751326AbcBURoO (ORCPT ); Sun, 21 Feb 2016 12:44:14 -0500 Received: from smtp1.mailbox.org (smtp1.mailbox.org [80.241.60.240]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.mailbox.org (Postfix) with ESMTPS id D457B43AFD for ; Sun, 21 Feb 2016 15:07:18 +0100 (CET) Received: from smtp1.mailbox.org ([80.241.60.240]) by hefe.heinlein-support.de (hefe.heinlein-support.de [91.198.250.172]) (amavisd-new, port 10030) with ESMTP id qcrunSSu79C5 for ; Sun, 21 Feb 2016 15:07:16 +0100 (CET) In-Reply-To: <56C8BE6D.7050409@m-reimer.de> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: linux-input@vger.kernel.org Resending message. Is the list broken? On 02/20/2016 08:28 PM, Manuel Reimer wrote: > But what could be the mistake, which allowed me to create a device > driver which actually only supports FF_RUMBLE? Are there any special > driver parameters that have to be present, so the kernel side emulation > gets active? After searching through the kernel source, I've found some more information. Event emulation is done here: https://github.com/torvalds/linux/blob/master/drivers/input/ff-memless.c And this is not triggered by the uinput kernel driver at all. Would it be possible to add this feature to uinput? Let's say: If only "FF_RUMBLE" is set and the device reports to be only able to handle one ff event, then initialize ff-memless. I could try to create a patch for that, but it would be nice if someone of the "linux input pros" could at least tell what they think about this? Is this possible at all or is there anything which would make this fail? Thanks in advance. Best regards Manuel