From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Likely Subject: Re: [PATCH V3 1/5] i2c: Add irq_gpio field to struct i2c_client, i2c_board_info. Date: Mon, 19 Sep 2011 22:16:29 -0600 Message-ID: <20110920041629.GC30517@ponder.secretlab.ca> References: <1314914676-28397-1-git-send-email-swarren@nvidia.com> <20110902085620.4ad918c4@endymion.delvare> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20110902085620.4ad918c4-R0o5gVi9kd7kN2dkZ6Wm7A@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jean Delvare Cc: Stephen Warren , Greg Kroah-Hartman , Ben Dooks , Jonathan Cameron , Arnd Bergmann , Russell King , Andrew Chew , linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-tegra@vger.kernel.org On Fri, Sep 02, 2011 at 08:56:20AM +0200, Jean Delvare wrote: > Stephen, > > Can you please fix your e-mail client / system / whatever so that your > patch series are no longer sent duplicated? > > On Thu, 1 Sep 2011 16:04:27 -0600, Stephen Warren wrote: > > Some devices use a single pin as both an IRQ and a GPIO. In that case, > > irq_gpio is the GPIO ID for that pin. Not all drivers use this feature. > > Where they do, and the use of this feature is optional, and the system > > wishes to disable this feature, this field must be explicitly set to a > > defined invalid GPIO ID, such as -1. > > > > Signed-off-by: Stephen Warren > > --- > > v3: Also add the field to i2c_board_info, and copy the field from > > i2c_board_info to i2c_client upon instantiation > > I don't get the idea. The i2c core doesn't make any use of the field, > and that field will only be used by a few drivers amongst the 420+ > i2c drivers in the tree. This looks like a waste of memory. What's wrong > with including the new field in the private platform or arch data > structure for drivers which need it? I have to second the concern; but for a different reason. This shouldn't even remotely be necessary. If the pin is used as an interrupt, then interrupt controller driver (which I would assume is also the gpio controller driver) should be responsible for setting up the pin so that it can be used correctly as a irq line. Why does the gpio number need to be explicitly passed? g. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751775Ab1ITEQd (ORCPT ); Tue, 20 Sep 2011 00:16:33 -0400 Received: from mail-gy0-f174.google.com ([209.85.160.174]:51145 "EHLO mail-gy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750944Ab1ITEQb (ORCPT ); Tue, 20 Sep 2011 00:16:31 -0400 Date: Mon, 19 Sep 2011 22:16:29 -0600 From: Grant Likely To: Jean Delvare Cc: Stephen Warren , Greg Kroah-Hartman , Ben Dooks , Jonathan Cameron , Arnd Bergmann , Russell King , Andrew Chew , linux-iio@vger.kernel.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org, linux-i2c@vger.kernel.org, spi-devel-general@lists.sourceforge.net Subject: Re: [PATCH V3 1/5] i2c: Add irq_gpio field to struct i2c_client, i2c_board_info. Message-ID: <20110920041629.GC30517@ponder.secretlab.ca> References: <1314914676-28397-1-git-send-email-swarren@nvidia.com> <20110902085620.4ad918c4@endymion.delvare> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110902085620.4ad918c4@endymion.delvare> 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 On Fri, Sep 02, 2011 at 08:56:20AM +0200, Jean Delvare wrote: > Stephen, > > Can you please fix your e-mail client / system / whatever so that your > patch series are no longer sent duplicated? > > On Thu, 1 Sep 2011 16:04:27 -0600, Stephen Warren wrote: > > Some devices use a single pin as both an IRQ and a GPIO. In that case, > > irq_gpio is the GPIO ID for that pin. Not all drivers use this feature. > > Where they do, and the use of this feature is optional, and the system > > wishes to disable this feature, this field must be explicitly set to a > > defined invalid GPIO ID, such as -1. > > > > Signed-off-by: Stephen Warren > > --- > > v3: Also add the field to i2c_board_info, and copy the field from > > i2c_board_info to i2c_client upon instantiation > > I don't get the idea. The i2c core doesn't make any use of the field, > and that field will only be used by a few drivers amongst the 420+ > i2c drivers in the tree. This looks like a waste of memory. What's wrong > with including the new field in the private platform or arch data > structure for drivers which need it? I have to second the concern; but for a different reason. This shouldn't even remotely be necessary. If the pin is used as an interrupt, then interrupt controller driver (which I would assume is also the gpio controller driver) should be responsible for setting up the pin so that it can be used correctly as a irq line. Why does the gpio number need to be explicitly passed? g.