From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roger Quadros Subject: Re: [PATCH 4/6] pinctrl: single: Add support for wake-up interrupts Date: Fri, 11 Oct 2013 11:56:30 +0300 Message-ID: <5257BD3E.5000707@ti.com> References: <20131003054104.8941.88857.stgit@localhost> <20131003054221.8941.87801.stgit@localhost> <5256AA7F.8030005@ti.com> <20131010160018.GA29913@atomide.com> <20131010162015.GC29913@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Linus Walleij Cc: "devicetree@vger.kernel.org" , Grygorii Strashko , Tony Lindgren , "linux-kernel@vger.kernel.org" , Peter Ujfalusi , Prakash Manjunathappa , Haojian Zhuang , =?ISO-8859-1?Q?Beno=EEt_Cousson?= , Linux-OMAP , "linux-arm-kernel@lists.infradead.org" List-Id: devicetree@vger.kernel.org On 10/11/2013 11:00 AM, Linus Walleij wrote: > On Thu, Oct 10, 2013 at 6:20 PM, Tony Lindgren wrote: >> * Linus Walleij [131010 09:19]: >>> On Thu, Oct 10, 2013 at 6:00 PM, Tony Lindgren wrote: >>>> * Roger Quadros [131010 06:32]: >>>>> >>>>> I tried testing this with the USB EHCI driver, but I'm not getting wake up interrupts >>>>> while the system is still running and only the EHCI controller is runtime suspended. >>>>> >>>>> It seems we need to somehow call _reconfigure_io_chain() to update the daisy chain >>>>> whenever the pad wakeup_enable bit is changed. >>>> >>>> Sounds like this is on omap3? Have you tried calling pcs_soc->rearm() in the >>>> pcs_irq_handle() like the comments there suggest? At least for me that keeps >>>> the wake-up interrupts continuously running on omap3 instead of just idle modes. >>> >>> If the rearm() function is calling this _reconfigure_io_chain my comments >>> on the fact that this is something that should be handled by the pin >>> control driver still apply I think .... >> >> Yes, except that the reconfigure_io_chain registers are in the PRM module, not in >> the SCM module where the pinctrl registers are.. And that shared PRM interrupt is >> used mostly for the internal domain wake-ups, so we should keep that in the PRM >> driver. > > That depends. > > One-iorange-equals-one-driver is a fallacy, especially given that MFD for > memory-mapped things exist for a reason. +1 Another place I faced a similar problem was the OMAP control module, which contains registers for a number of different non related peripherals. (e.g. PHY for USB, SATA, Display clock, etc) > > 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. cheers, -roger