Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758434Ab3JKPoI (ORCPT ); Fri, 11 Oct 2013 11:44:08 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:42975 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758405Ab3JKPoE (ORCPT ); Fri, 11 Oct 2013 11:44:04 -0400 Message-ID: <52581CA7.20606@ti.com> Date: Fri, 11 Oct 2013 21:13:35 +0530 From: Balaji T K User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120827 Thunderbird/15.0 MIME-Version: 1.0 To: Tony Lindgren CC: Roger Quadros , Linus Walleij , "linux-arm-kernel@lists.infradead.org" , "devicetree@vger.kernel.org" , Grygorii Strashko , "linux-kernel@vger.kernel.org" , Peter Ujfalusi , Haojian Zhuang , =?ISO-8859-1?Q?Beno=EEt_Co?= =?ISO-8859-1?Q?usson?= , Linux-OMAP Subject: Re: [PATCH 4/6] pinctrl: single: Add support for wake-up interrupts References: <20131003054104.8941.88857.stgit@localhost> <20131003054221.8941.87801.stgit@localhost> <5256AA7F.8030005@ti.com> <20131010160018.GA29913@atomide.com> <20131010162015.GC29913@atomide.com> <5257BD3E.5000707@ti.com> <20131011153654.GN29913@atomide.com> In-Reply-To: <20131011153654.GN29913@atomide.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1733 Lines: 36 On Friday 11 October 2013 09:06 PM, Tony Lindgren wrote: >>> What the pin control driver should do is control the pins. Whether the registers >>> are spread out in the entire IO-memory does not matter. We did have one system >>> which placed the IO-muxing together with each peripheral (!) and I did >>> still want >>> that to be handled by a single pinctrl driver picking out windows to all these >>> IO-ranges. >>> >>> Things like the PRM which has (my guess) a gazillion registers related to its >>> deep-core SoC stuff should be handled by things like >>> drivers/mfd/syscon.c, which means it is dead simple for some other driver >>> using "just this one register" in that range to get a handle at it and poke it >>> using syscon_node_to_regmap() (just derference an ampersand ref) >>> syscon_regmap_lookup_by_compatible() (use a compatible string) >>> all returning a regmap * that you can use to poke these registers. >> >> The register handling is fine. But how do we deal with resource handling? >> e.g. the block that has the deep-core registers might need to be clocked or powered >> before the registers can be accessed. > > Right, that's the key issue here. The register access would have to be conditional > based on the hardware modules PM state. Otherwise we'll have hard to trace hangs > and oopses. > Hi Tony, How are the clocks/power state currently handled in case of omap4_pmx_core, omap4_pmx_wkup register access via pinctrl-single ? Thanks and Regards, Balaji T K -- 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/