From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 73C91C02194 for ; Tue, 4 Feb 2025 14:35:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Subject:CC:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=NHaMrj0jT4p57TUFTw9OqaWMWcyKG2QUonGo1kGXO1k=; b=iKqsDDz7iTRmnqvhzmM97rbPpL gFRAMe4RYvVwSuSVjjXflw3WVj9Kec6IVnDSQ8vh36TkuT3vHw4tLcAR125Mc4HRUzRGSdJWfzdfP fVAA+W+MZnvgBYWfoekgxcLWYqc3Ud5Z3i/BKn4kxwDAWw4oYeOVWs9Ty+a+8L/sPcXha+xBDcIEo wjy1lHnb/S6Yzu7CVyoLY+KVWdPCMqxmMaxYwC6uIxZbb05wM3w356erpDCFog2g1J2GRXrBjvMQ1 kGopL1X9RaIbOpB1vcNRg35yoLdxg4yFfnviszGOSHs9hwwVGR1yX4YytiS+an0vKjrWkCOmpGGlE fBgL4mHQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tfK19-00000000gGB-477z; Tue, 04 Feb 2025 14:35:11 +0000 Received: from frasgout.his.huawei.com ([185.176.79.56]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tfJzN-00000000fzB-2TdE for linux-arm-kernel@lists.infradead.org; Tue, 04 Feb 2025 14:33:23 +0000 Received: from mail.maildlp.com (unknown [172.18.186.216]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4YnQkt2SxVz6L4vs; Tue, 4 Feb 2025 22:30:30 +0800 (CST) Received: from frapeml500008.china.huawei.com (unknown [7.182.85.71]) by mail.maildlp.com (Postfix) with ESMTPS id B29B1140B67; Tue, 4 Feb 2025 22:33:05 +0800 (CST) Received: from localhost (10.203.177.66) by frapeml500008.china.huawei.com (7.182.85.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Tue, 4 Feb 2025 15:33:04 +0100 Date: Tue, 4 Feb 2025 14:33:03 +0000 From: Jonathan Cameron To: Ulf Hansson CC: Daniel Lezcano , Claudiu , , , , , , , , , , , , , , , , , , "Claudiu Beznea" Subject: Re: [PATCH 2/6] thermal: of: Export non-devres helper to register/unregister thermal zone Message-ID: <20250204143303.0000174a@huawei.com> In-Reply-To: References: <20250103163805.1775705-1-claudiu.beznea.uj@bp.renesas.com> <20250103163805.1775705-3-claudiu.beznea.uj@bp.renesas.com> <46c8e8ff-ea39-4dbd-a26c-67fcabf4b589@linaro.org> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.203.177.66] X-ClientProxiedBy: lhrpeml100009.china.huawei.com (7.191.174.83) To frapeml500008.china.huawei.com (7.182.85.71) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250204_063321_923217_86F78158 X-CRM114-Status: GOOD ( 38.90 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, 15 Jan 2025 16:42:37 +0100 Ulf Hansson wrote: > On Thu, 9 Jan 2025 at 18:34, Daniel Lezcano w= rote: > > > > > > Ulf, > > > > can you have a look at this particular patch please ? > > > > Perhaps this scenario already happened in the past and there is an > > alternative to fix it instead of this proposed change =20 >=20 > I think the patch makes sense. >=20 > If there is a PM domain that is attached to the device that is > managing the clocks for the thermal zone, the detach procedure > certainly needs to be well controlled/synchronized. >=20 Does this boil down to the same issue as https://lore.kernel.org/linux-iio/20250128105908.0000353b@huawei.com/ ? Just to point out there is another way like is done in i2c: https://elixir.bootlin.com/linux/v6.12.6/source/drivers/i2c/i2c-core-base.c= #L630 Register a devres_release_group() in bus probe() and release it before the dev_pm_domain_detach() call. That keeps the detach procedure well controlled and synchronized as it is entirely in control of the driver. That IIO thread has kind of died out for now though with no resolution so far. Jonathan > > > > > > On 03/01/2025 17:38, Claudiu wrote: =20 > > > From: Claudiu Beznea > > > > > > On the Renesas RZ/G3S (and other Renesas SoCs, e.g., RZ/G2{L, LC, UL}= ), > > > clocks are managed through PM domains. These PM domains, registered on > > > behalf of the clock controller driver, are configured with > > > GENPD_FLAG_PM_CLK. In most of the Renesas drivers used by RZ SoCs, the > > > clocks are enabled/disabled using runtime PM APIs. > > > > > > During probe, devices are attached to the PM domain controlling their > > > clocks. Similarly, during removal, devices are detached from the PM d= omain. > > > > > > The detachment call stack is as follows: > > > > > > device_driver_detach() -> > > > device_release_driver_internal() -> > > > __device_release_driver() -> > > > device_remove() -> > > > platform_remove() -> > > > dev_pm_domain_detach() > > > > > > In the upcoming Renesas RZ/G3S thermal driver, the > > > struct thermal_zone_device_ops::change_mode API is implemented to > > > start/stop the thermal sensor unit. Register settings are updated wit= hin > > > the change_mode API. > > > > > > In case devres helpers are used for thermal zone register/unregister = the > > > struct thermal_zone_device_ops::change_mode API is invoked when the > > > driver is unbound. The identified call stack is as follows: > > > > > > device_driver_detach() -> > > > device_release_driver_internal() -> > > > device_unbind_cleanup() -> > > > devres_release_all() -> > > > devm_thermal_of_zone_release() -> > > > thermal_zone_device_disable() -> > > > thermal_zone_device_set_mode() -> > > > rzg3s_thermal_change_mode() > > > > > > The device_unbind_cleanup() function is called after the thermal devi= ce is > > > detached from the PM domain (via dev_pm_domain_detach()). > > > > > > The rzg3s_thermal_change_mode() implementation calls > > > pm_runtime_resume_and_get()/pm_runtime_put_autosuspend() before/after > > > accessing the registers. However, during the unbind scenario, the > > > devm_thermal_of_zone_release() is invoked after dev_pm_domain_detach(= ). > > > Consequently, the clocks are not enabled, as the device is removed fr= om > > > the PM domain at this time, leading to an Asynchronous SError Interru= pt. > > > The system cannot be used after this. > > > > > > Add thermal_of_zone_register()/thermal_of_zone_unregister(). These wi= ll > > > be used in the upcomming RZ/G3S thermal driver. > > > > > > Signed-off-by: Claudiu Beznea =20 >=20 > Reviewed-by: Ulf Hansson >=20 > Kind regards > Uffe >=20 > > > --- > > > drivers/thermal/thermal_of.c | 8 +++++--- > > > include/linux/thermal.h | 14 ++++++++++++++ > > > 2 files changed, 19 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_o= f.c > > > index fab11b98ca49..8fc35d20db60 100644 > > > --- a/drivers/thermal/thermal_of.c > > > +++ b/drivers/thermal/thermal_of.c > > > @@ -329,11 +329,12 @@ static bool thermal_of_should_bind(struct therm= al_zone_device *tz, > > > * > > > * @tz: a pointer to the thermal zone structure > > > */ > > > -static void thermal_of_zone_unregister(struct thermal_zone_device *t= z) > > > +void thermal_of_zone_unregister(struct thermal_zone_device *tz) > > > { > > > thermal_zone_device_disable(tz); > > > thermal_zone_device_unregister(tz); > > > } > > > +EXPORT_SYMBOL_GPL(thermal_of_zone_unregister); > > > > > > /** > > > * thermal_of_zone_register - Register a thermal zone with device n= ode > > > @@ -355,8 +356,8 @@ static void thermal_of_zone_unregister(struct the= rmal_zone_device *tz) > > > * - ENOMEM: if one structure can not be allocated > > > * - Other negative errors are returned by the underlying called f= unctions > > > */ > > > -static struct thermal_zone_device *thermal_of_zone_register(struct d= evice_node *sensor, int id, void *data, > > > - const struc= t thermal_zone_device_ops *ops) > > > +struct thermal_zone_device *thermal_of_zone_register(struct device_n= ode *sensor, int id, void *data, > > > + const struct therm= al_zone_device_ops *ops) > > > { > > > struct thermal_zone_device_ops of_ops =3D *ops; > > > struct thermal_zone_device *tz; > > > @@ -429,6 +430,7 @@ static struct thermal_zone_device *thermal_of_zon= e_register(struct device_node * > > > > > > return ERR_PTR(ret); > > > } > > > +EXPORT_SYMBOL_GPL(thermal_of_zone_register); > > > > > > static void devm_thermal_of_zone_release(struct device *dev, void *= res) > > > { > > > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > > > index 69f9bedd0ee8..adbb4092a064 100644 > > > --- a/include/linux/thermal.h > > > +++ b/include/linux/thermal.h > > > @@ -195,13 +195,23 @@ struct thermal_zone_params { > > > > > > /* Function declarations */ > > > #ifdef CONFIG_THERMAL_OF > > > +struct thermal_zone_device *thermal_of_zone_register(struct device_n= ode *sensor, int id, void *data, > > > + const struct therm= al_zone_device_ops *ops); > > > struct thermal_zone_device *devm_thermal_of_zone_register(struct de= vice *dev, int id, void *data, > > > const struct = thermal_zone_device_ops *ops); > > > > > > +void thermal_of_zone_unregister(struct thermal_zone_device *tz); > > > void devm_thermal_of_zone_unregister(struct device *dev, struct the= rmal_zone_device *tz); > > > > > > #else > > > > > > +static inline > > > +struct thermal_zone_device *thermal_of_zone_register(struct device_n= ode *sensor, int id, void *data, > > > + const struct therm= al_zone_device_ops *ops) > > > +{ > > > + return ERR_PTR(-ENOTSUPP); > > > +} > > > + > > > static inline > > > struct thermal_zone_device *devm_thermal_of_zone_register(struct de= vice *dev, int id, void *data, > > > const struct = thermal_zone_device_ops *ops) > > > @@ -209,6 +219,10 @@ struct thermal_zone_device *devm_thermal_of_zone= _register(struct device *dev, in > > > return ERR_PTR(-ENOTSUPP); > > > } > > > > > > +static inline void thermal_of_zone_unregister(struct thermal_zone_de= vice *tz) > > > +{ > > > +} > > > + > > > static inline void devm_thermal_of_zone_unregister(struct device *d= ev, > > > struct thermal_zone_= device *tz) > > > { =20 > > > > > > -- > > Linaro.org =E2=94=82 Open source software for = ARM SoCs > > > > Follow Linaro: Facebook | > > Twitter | > > Blog =20 >=20