From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756982Ab3A0XxD (ORCPT ); Sun, 27 Jan 2013 18:53:03 -0500 Received: from mga01.intel.com ([192.55.52.88]:37170 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756963Ab3A0Xw7 (ORCPT ); Sun, 27 Jan 2013 18:52:59 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,547,1355126400"; d="scan'208";a="279037732" Date: Mon, 28 Jan 2013 00:52:59 +0100 From: Samuel Ortiz To: Lee Jones Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, arnd@arndb.de, linus.walleij@stericsson.com Subject: Re: [PATCH 09/26] mfd: ab8500-debugfs: Provide a means for a user subscribe to IRQs Message-ID: <20130127235259.GO1174@sortiz-mobl> References: <1358254566-12419-1-git-send-email-lee.jones@linaro.org> <1358254566-12419-10-git-send-email-lee.jones@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1358254566-12419-10-git-send-email-lee.jones@linaro.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Lee, On Tue, Jan 15, 2013 at 12:55:49PM +0000, Lee Jones wrote: > Allow users to subscribe to and view IRQ events live from debugfs. I seem to remember that I got a similar patch some time ago for the same purpose and my answer was: Please use a UIO driver for this. There already is such driver, it's uio_pdrv_genirq. What your debugfs registration entry could do is adding a platform device for the specific interrupt number. This would avoid the irq handler registration and the sysfs entry creation, both things I believe are not very elegant and open coded. It also gives you an IRQ count implementation. Ideally, the UIO framework could be improved to support IRQ ranges (through IRQ domains) instead of the current single interrupt number. Have you considered going through that path ? Cheers, Samuel. -- Intel Open Source Technology Centre http://oss.intel.com/