From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756613Ab3GQRFm (ORCPT ); Wed, 17 Jul 2013 13:05:42 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:47692 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755507Ab3GQRFk (ORCPT ); Wed, 17 Jul 2013 13:05:40 -0400 Message-ID: <51E6CCB6.2000907@ti.com> Date: Wed, 17 Jul 2013 19:56:22 +0300 From: Grygorii Strashko User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130623 Thunderbird/17.0.7 MIME-Version: 1.0 To: Tony Lindgren CC: Kevin Hilman , , , , , Linus Walleij , Stephen Warren Subject: Re: [PATCH 2/3] ARM: OMAP2+: omap_device: add pinctrl handling References: <1374061312-25469-1-git-send-email-grygorii.strashko@ti.com> <1374061312-25469-3-git-send-email-grygorii.strashko@ti.com> <20130717153838.GJ7656@atomide.com> In-Reply-To: <20130717153838.GJ7656@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 On 07/17/2013 06:38 PM, Tony Lindgren wrote: > * Grygorii Strashko [130717 04:49]: >> Before switching to DT pinctrl states of OMAP IPs have been handled by hwmod >> framework. After switching to DT-boot the pinctrl handling was dropped from >> hwmod framework and, as it was recommended, OMAP IP's drivers have to be updated >> to handle pinctrl states by itself using pinctrl_pm_select_xx() helpers >> (see http://lists.infradead.org/pipermail/linux-arm-kernel/2013-June/173514.html) >> >> But this is not right for OMAP2+ SoC where real IPs state is controlled >> by omap_device core which enables/disables modules & clocks actually. > > I'm not convinced we should try to handle this in a generic way > as only some devices need dynamic remuxing of some pins. > >> For example, if OMAP I2C driver will handle pinctrl state during system wide >> suspend the following issue may occure: >> - suspend_noirq - I2C device can be still active because of PM auto-suspend >> |-_od_suspend_noirq >> |- omap_i2c_suspend_noirq >> |- PINs state set to SLEEP >> |- pm_generic_runtime_suspend >> |- omap_i2c_runtime_suspend() >> |- PINs state set to IDLE <--- *oops* PINs state is IDLE and not SLEEP >> |- omap_device_idle() >> |- omap_hwmod_idle() >> |- _idle() >> |- disbale module (sysc&clocks) > > And in this example you are assuming that you need separate idle and > sleep states, which is not true at least for most cases I've seen. I don't need both states (at least right now) :), but - if any OMAP2+ driver will have two states defined: "idle" and "sleep" - and if it will try to manage them from drivers callbacks only using pure calls to pinctrl_pm_select_xx() helpers the "idle" state will be selected during suspend and *not* "sleep". > > It is possible that am33xx needs separate idle and sleep states, but > most likely only for some pins. For omap[345] we can get away with > just the default state for most cases. > In case, if only "default" state is defined for device - nothing will be done by OMAP device framework for it (I mean any call to pinctrl_pm_select_xx() will do nothing - it just checks that there is no state and returns 0). > Regards, > > Tony > Regards, - grygorii From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grygorii Strashko Subject: Re: [PATCH 2/3] ARM: OMAP2+: omap_device: add pinctrl handling Date: Wed, 17 Jul 2013 19:56:22 +0300 Message-ID: <51E6CCB6.2000907@ti.com> References: <1374061312-25469-1-git-send-email-grygorii.strashko@ti.com> <1374061312-25469-3-git-send-email-grygorii.strashko@ti.com> <20130717153838.GJ7656@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130717153838.GJ7656@atomide.com> Sender: linux-omap-owner@vger.kernel.org To: Tony Lindgren Cc: Kevin Hilman , linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, Linus Walleij , Stephen Warren List-Id: devicetree@vger.kernel.org On 07/17/2013 06:38 PM, Tony Lindgren wrote: > * Grygorii Strashko [130717 04:49]: >> Before switching to DT pinctrl states of OMAP IPs have been handled by hwmod >> framework. After switching to DT-boot the pinctrl handling was dropped from >> hwmod framework and, as it was recommended, OMAP IP's drivers have to be updated >> to handle pinctrl states by itself using pinctrl_pm_select_xx() helpers >> (see http://lists.infradead.org/pipermail/linux-arm-kernel/2013-June/173514.html) >> >> But this is not right for OMAP2+ SoC where real IPs state is controlled >> by omap_device core which enables/disables modules & clocks actually. > > I'm not convinced we should try to handle this in a generic way > as only some devices need dynamic remuxing of some pins. > >> For example, if OMAP I2C driver will handle pinctrl state during system wide >> suspend the following issue may occure: >> - suspend_noirq - I2C device can be still active because of PM auto-suspend >> |-_od_suspend_noirq >> |- omap_i2c_suspend_noirq >> |- PINs state set to SLEEP >> |- pm_generic_runtime_suspend >> |- omap_i2c_runtime_suspend() >> |- PINs state set to IDLE <--- *oops* PINs state is IDLE and not SLEEP >> |- omap_device_idle() >> |- omap_hwmod_idle() >> |- _idle() >> |- disbale module (sysc&clocks) > > And in this example you are assuming that you need separate idle and > sleep states, which is not true at least for most cases I've seen. I don't need both states (at least right now) :), but - if any OMAP2+ driver will have two states defined: "idle" and "sleep" - and if it will try to manage them from drivers callbacks only using pure calls to pinctrl_pm_select_xx() helpers the "idle" state will be selected during suspend and *not* "sleep". > > It is possible that am33xx needs separate idle and sleep states, but > most likely only for some pins. For omap[345] we can get away with > just the default state for most cases. > In case, if only "default" state is defined for device - nothing will be done by OMAP device framework for it (I mean any call to pinctrl_pm_select_xx() will do nothing - it just checks that there is no state and returns 0). > Regards, > > Tony > Regards, - grygorii From mboxrd@z Thu Jan 1 00:00:00 1970 From: grygorii.strashko@ti.com (Grygorii Strashko) Date: Wed, 17 Jul 2013 19:56:22 +0300 Subject: [PATCH 2/3] ARM: OMAP2+: omap_device: add pinctrl handling In-Reply-To: <20130717153838.GJ7656@atomide.com> References: <1374061312-25469-1-git-send-email-grygorii.strashko@ti.com> <1374061312-25469-3-git-send-email-grygorii.strashko@ti.com> <20130717153838.GJ7656@atomide.com> Message-ID: <51E6CCB6.2000907@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 07/17/2013 06:38 PM, Tony Lindgren wrote: > * Grygorii Strashko [130717 04:49]: >> Before switching to DT pinctrl states of OMAP IPs have been handled by hwmod >> framework. After switching to DT-boot the pinctrl handling was dropped from >> hwmod framework and, as it was recommended, OMAP IP's drivers have to be updated >> to handle pinctrl states by itself using pinctrl_pm_select_xx() helpers >> (see http://lists.infradead.org/pipermail/linux-arm-kernel/2013-June/173514.html) >> >> But this is not right for OMAP2+ SoC where real IPs state is controlled >> by omap_device core which enables/disables modules & clocks actually. > > I'm not convinced we should try to handle this in a generic way > as only some devices need dynamic remuxing of some pins. > >> For example, if OMAP I2C driver will handle pinctrl state during system wide >> suspend the following issue may occure: >> - suspend_noirq - I2C device can be still active because of PM auto-suspend >> |-_od_suspend_noirq >> |- omap_i2c_suspend_noirq >> |- PINs state set to SLEEP >> |- pm_generic_runtime_suspend >> |- omap_i2c_runtime_suspend() >> |- PINs state set to IDLE <--- *oops* PINs state is IDLE and not SLEEP >> |- omap_device_idle() >> |- omap_hwmod_idle() >> |- _idle() >> |- disbale module (sysc&clocks) > > And in this example you are assuming that you need separate idle and > sleep states, which is not true at least for most cases I've seen. I don't need both states (at least right now) :), but - if any OMAP2+ driver will have two states defined: "idle" and "sleep" - and if it will try to manage them from drivers callbacks only using pure calls to pinctrl_pm_select_xx() helpers the "idle" state will be selected during suspend and *not* "sleep". > > It is possible that am33xx needs separate idle and sleep states, but > most likely only for some pins. For omap[345] we can get away with > just the default state for most cases. > In case, if only "default" state is defined for device - nothing will be done by OMAP device framework for it (I mean any call to pinctrl_pm_select_xx() will do nothing - it just checks that there is no state and returns 0). > Regards, > > Tony > Regards, - grygorii