Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754828Ab2KWMjZ (ORCPT ); Fri, 23 Nov 2012 07:39:25 -0500 Received: from mail-oa0-f46.google.com ([209.85.219.46]:63626 "EHLO mail-oa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750896Ab2KWMjY (ORCPT ); Fri, 23 Nov 2012 07:39:24 -0500 MIME-Version: 1.0 In-Reply-To: <20121123093633.GD17471@gmail.com> References: <20121122112451.GE4328@gmail.com> <20121123093633.GD17471@gmail.com> Date: Fri, 23 Nov 2012 18:09:23 +0530 Message-ID: Subject: Re: [PATCH V2 2/2] mfd: stmpe: Extend DT support in stmpe driver From: Viresh Kumar To: Lee Jones Cc: sameo@linux.intel.com, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org, spear-devel@list.st.com, Vipul Kumar Samar Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1805 Lines: 50 On 23 November 2012 15:06, Lee Jones wrote: > On Fri, 23 Nov 2012, Viresh Kumar wrote: >> pdev = platform_device_alloc(cell->name, id + cell->id); >> >> This is required when we have multiple instances of MFD device present >> on board. How do you want me to handle this ? > > There are lots of examples of this already. I have to leave something > to the imagination, or I'll be requesting a cut of your salary. :D My manager already reduced my salary by 20% after reading this mail :( Ok, this is what my understanding of whole this is. Platform devices are named like: - pdev-name: if id passed in pdev.id is -1 - pdev-name.0[1|2|...]: if id passed is 0[1|2|...] - pdev-name.: if id passed is -2 Now, we don't declare cell->id fields and they are currently zero and so value is passed from pdata->id field. So, for example with multiple instances of stmpe on a board, we have: - stmpe-0: //Name just for reference... - stmpe-gpio.0 - stmpe-ts.0 - stmpe-1: - stmpe-gpio.1 - stmpe-ts.1 - stmpe-2: - stmpe-gpio.2 - stmpe-ts.2 I main idea is to distinguish various instances of sub modules, like stmpe-gpio. And this works well with non-DT support we have currently. With DT, i am not sure how should we pass id field to mfd_add_devices(). If we pass it -1, then multiple instances will have same name: "stmpe-gpio" Sorry, for my lack of knowledge. Don't send another mail with salary cut suggestion as that will make it -40% in total ;) Thanks for reviewing :) -- viresh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/