| Message ID | 20200320014107.26087-4-thara.gopinath@linaro.org (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
| Series | Introduce Power domain based warming device driver | expand |
On Fri, 20 Mar 2020 at 02:41, Thara Gopinath <thara.gopinath@linaro.org> wrote: > > Resources modeled as power domains in linux kernel can be used to warm the > SoC(eg. mx power domain on sdm845). To support this feature, introduce a > generic power domain warming device driver that can be plugged into the > thermal framework (The thermal framework itself requires further > modifiction to support a warming device in place of a cooling device. > Those extensions are not introduced in this patch series). > > Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org> > --- > > v3->v4: > - Removed late_init hook pd_warming_device_ops. > - Use of_genpd_add_device instead of pm_genpd_add_device to attach > device to the generic power domain. > - Use thermal_of_cooling_device_parent_register to register the > cooling device so that the device with genpd attached can be > made parent of the cooling device. > - With above changes, remove reference to generic_pm_domain in > pd_warming_device. > > v4->v5: > - All the below changes are as per Ulf's review comments. > - Renamed pwr_domain_warming.c and pwr_domain_warming.h to > pd_warming.c and pd_warming.h. > - Renamed pwr_domain_warming_register API to > of_pd_warming_register. > - Dropped in-param pd_name to of_pd_warming_register. > - Introduced ID allocator to uniquely identify each power domain > warming device. > - Introduced pd_warming_release to handle device kfree for > pd_warming_device. > - Introduced pm_genpd_remove_device in the error exit path > of of_pd_warming_register. > > drivers/thermal/Kconfig | 10 +++ > drivers/thermal/Makefile | 2 + > drivers/thermal/pd_warming.c | 168 +++++++++++++++++++++++++++++++++++ > include/linux/pd_warming.h | 29 ++++++ > 4 files changed, 209 insertions(+) > create mode 100644 drivers/thermal/pd_warming.c > create mode 100644 include/linux/pd_warming.h > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig > index 4d6753f2b18f..92522d541d0e 100644 > --- a/drivers/thermal/Kconfig > +++ b/drivers/thermal/Kconfig > @@ -206,6 +206,16 @@ config DEVFREQ_THERMAL > > If you want this support, you should say Y here. > > +config PWR_DOMAIN_WARMING_THERMAL > + bool "Power Domain based warming device" > + depends on PM_GENERIC_DOMAINS_OF > + help > + This implements the generic power domain based warming > + mechanism through increasing the performance state of > + a power domain. > + > + If you want this support, you should say Y here. > + > config THERMAL_EMULATION > bool "Thermal emulation mode support" > help > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile > index 8c8ed7b79915..7db87a779126 100644 > --- a/drivers/thermal/Makefile > +++ b/drivers/thermal/Makefile > @@ -28,6 +28,8 @@ thermal_sys-$(CONFIG_CLOCK_THERMAL) += clock_cooling.o > # devfreq cooling > thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o > > +thermal_sys-$(CONFIG_PWR_DOMAIN_WARMING_THERMAL) += pd_warming.o > + > # platform thermal drivers > obj-y += broadcom/ > obj-$(CONFIG_THERMAL_MMIO) += thermal_mmio.o > diff --git a/drivers/thermal/pd_warming.c b/drivers/thermal/pd_warming.c > new file mode 100644 > index 000000000000..c0854d2e4b92 > --- /dev/null > +++ b/drivers/thermal/pd_warming.c > @@ -0,0 +1,168 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2019, Linaro Ltd > + */ > +#include <linux/err.h> > +#include <linux/kernel.h> > +#include <linux/init.h> > +#include <linux/of_device.h> > +#include <linux/platform_device.h> > +#include <linux/module.h> > +#include <linux/pm_runtime.h> > +#include <linux/slab.h> > +#include <linux/pd_warming.h> > + > +struct pd_warming_device { > + struct thermal_cooling_device *cdev; > + struct device dev; > + int id; > + int max_state; > + int cur_state; > + bool runtime_resumed; > +}; > + > +static DEFINE_IDA(pd_ida); > + > +static int pd_wdev_get_max_state(struct thermal_cooling_device *cdev, > + unsigned long *state) > +{ > + struct pd_warming_device *pd_wdev = cdev->devdata; > + > + *state = pd_wdev->max_state; > + return 0; > +} > + > +static int pd_wdev_get_cur_state(struct thermal_cooling_device *cdev, > + unsigned long *state) > +{ > + struct pd_warming_device *pd_wdev = cdev->devdata; > + > + *state = dev_pm_genpd_get_performance_state(&pd_wdev->dev); > + > + return 0; > +} > + > +static int pd_wdev_set_cur_state(struct thermal_cooling_device *cdev, > + unsigned long state) > +{ > + struct pd_warming_device *pd_wdev = cdev->devdata; > + struct device *dev = &pd_wdev->dev; > + int ret; > + > + ret = dev_pm_genpd_set_performance_state(dev, state); > + > + if (ret) > + return ret; > + > + if (state && !pd_wdev->runtime_resumed) { > + ret = pm_runtime_get_sync(dev); > + pd_wdev->runtime_resumed = true; > + } else if (!state && pd_wdev->runtime_resumed) { > + ret = pm_runtime_put(dev); > + pd_wdev->runtime_resumed = false; > + } > + > + return ret; > +} > + > +static struct thermal_cooling_device_ops pd_warming_device_ops = { > + .get_max_state = pd_wdev_get_max_state, > + .get_cur_state = pd_wdev_get_cur_state, > + .set_cur_state = pd_wdev_set_cur_state, > +}; > + > +static void pd_warming_release(struct device *dev) > +{ > + kfree(dev); This is wrong, you should free a "struct pd_warming_device *". Use the "container of" macro to get it from 'dev'. > +} > + > +struct thermal_cooling_device * > +of_pd_warming_register(struct device *parent, int pd_id) > +{ > + struct pd_warming_device *pd_wdev; > + struct of_phandle_args pd_args; > + char cdev_name[THERMAL_NAME_LENGTH]; > + int ret; > + > + pd_wdev = kzalloc(sizeof(*pd_wdev), GFP_KERNEL); > + if (!pd_wdev) > + return ERR_PTR(-ENOMEM); > + > + dev_set_name(&pd_wdev->dev, "%s_%d_warming_dev", > + dev_name(parent), pd_id); > + pd_wdev->dev.parent = parent; > + pd_wdev->dev.release = pd_warming_release; > + > + ret = device_register(&pd_wdev->dev); > + if (ret) { > + put_device(&pd_wdev->dev); > + goto free_pd_wdev; > + } > + > + ret = ida_simple_get(&pd_ida, 0, 0, GFP_KERNEL); > + if (ret < 0) > + goto unregister_device; If you use and ida, you might as well use it as a part of the dev_set_name() above. That should give you a unique name, similar to how you use it for the cdev_name below. > + > + pd_wdev->id = ret; > + > + pd_args.np = parent->of_node; > + pd_args.args[0] = pd_id; > + pd_args.args_count = 1; > + > + ret = of_genpd_add_device(&pd_args, &pd_wdev->dev); > + > + if (ret) > + goto remove_ida; > + > + ret = dev_pm_genpd_performance_state_count(&pd_wdev->dev); > + if (ret < 0) > + goto out_genpd; > + > + pd_wdev->max_state = ret - 1; > + pm_runtime_enable(&pd_wdev->dev); > + pd_wdev->runtime_resumed = false; > + > + snprintf(cdev_name, sizeof(cdev_name), "thermal-pd-%d", pd_wdev->id); > + pd_wdev->cdev = thermal_of_cooling_device_register > + (NULL, cdev_name, pd_wdev, > + &pd_warming_device_ops); > + if (IS_ERR(pd_wdev->cdev)) { > + pr_err("unable to register %s cooling device\n", cdev_name); > + ret = PTR_ERR(pd_wdev->cdev); > + goto out_runtime_disable; > + } > + > + return pd_wdev->cdev; > + > +out_runtime_disable: > + pm_runtime_disable(&pd_wdev->dev); > +out_genpd: > + pm_genpd_remove_device(&pd_wdev->dev); > +remove_ida: > + ida_simple_remove(&pd_ida, pd_wdev->id); > +unregister_device: > + device_unregister(&pd_wdev->dev); > + pd_warming_release(&pd_wdev->dev); This is wrong, drop this. > +free_pd_wdev: > + kfree(pd_wdev); Since you should free this from the ->release() callback, there is no need to do this here. > + return ERR_PTR(ret); > +} > +EXPORT_SYMBOL_GPL(of_pd_warming_register); > + > +void pd_warming_unregister(struct thermal_cooling_device *cdev) > +{ > + struct pd_warming_device *pd_wdev = cdev->devdata; > + struct device *dev = &pd_wdev->dev; > + > + if (pd_wdev->runtime_resumed) { > + dev_pm_genpd_set_performance_state(dev, 0); > + pm_runtime_put(dev); > + pd_wdev->runtime_resumed = false; > + } > + pm_runtime_disable(dev); > + pm_genpd_remove_device(dev); > + ida_simple_remove(&pd_ida, pd_wdev->id); > + thermal_cooling_device_unregister(cdev); > + kfree(pd_wdev); Don't use kfree here, but instead device_unregister(dev); > +} > +EXPORT_SYMBOL_GPL(pd_warming_unregister); > diff --git a/include/linux/pd_warming.h b/include/linux/pd_warming.h > new file mode 100644 > index 000000000000..550a5683b56d > --- /dev/null > +++ b/include/linux/pd_warming.h > @@ -0,0 +1,29 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2019, Linaro Ltd. > + */ > +#ifndef __PWR_DOMAIN_WARMING_H__ > +#define __PWR_DOMAIN_WARMING_H__ > + > +#include <linux/pm_domain.h> > +#include <linux/thermal.h> > + > +#ifdef CONFIG_PWR_DOMAIN_WARMING_THERMAL > +struct thermal_cooling_device * > +of_pd_warming_register(struct device *parent, int pd_id); > + > +void pd_warming_unregister(struct thermal_cooling_device *cdev); > + > +#else > +static inline struct thermal_cooling_device * > +of_pd_warming_register(struct device *parent, int pd_id) > +{ > + return ERR_PTR(-ENOSYS); > +} > + > +static inline void > +pd_warming_unregister(struct thermal_cooling_device *cdev) > +{ > +} > +#endif /* CONFIG_PWR_DOMAIN_WARMING_THERMAL */ > +#endif /* __PWR_DOMAIN_WARMING_H__ */ > -- > 2.20.1 > Besides the few things above, this looks good to me. Kind regards Uffe
Hi Ulf, Thanks for the review! On 3/23/20 11:57 AM, Ulf Hansson wrote: --snip >> + >> +static void pd_warming_release(struct device *dev) >> +{ >> + kfree(dev); > > This is wrong, you should free a "struct pd_warming_device *". Use the > "container of" macro to get it from 'dev'. Will fix this. > >> +} >> + >> +struct thermal_cooling_device * >> +of_pd_warming_register(struct device *parent, int pd_id) >> +{ >> + struct pd_warming_device *pd_wdev; >> + struct of_phandle_args pd_args; >> + char cdev_name[THERMAL_NAME_LENGTH]; >> + int ret; >> + >> + pd_wdev = kzalloc(sizeof(*pd_wdev), GFP_KERNEL); >> + if (!pd_wdev) >> + return ERR_PTR(-ENOMEM); >> + >> + dev_set_name(&pd_wdev->dev, "%s_%d_warming_dev", >> + dev_name(parent), pd_id); >> + pd_wdev->dev.parent = parent; >> + pd_wdev->dev.release = pd_warming_release; >> + >> + ret = device_register(&pd_wdev->dev); >> + if (ret) { >> + put_device(&pd_wdev->dev); >> + goto free_pd_wdev; >> + } >> + >> + ret = ida_simple_get(&pd_ida, 0, 0, GFP_KERNEL); >> + if (ret < 0) >> + goto unregister_device; > > If you use and ida, you might as well use it as a part of the > dev_set_name() above. > > That should give you a unique name, similar to how you use it for the > cdev_name below. dev_set_name above already has a unique name with the power controller name and the power domain id. cdev on the other hand creates a virtual thermal device and needs a unique name. > >> + >> + pd_wdev->id = ret; >> + >> + pd_args.np = parent->of_node; >> + pd_args.args[0] = pd_id; >> + pd_args.args_count = 1; >> + >> + ret = of_genpd_add_device(&pd_args, &pd_wdev->dev); >> + >> + if (ret) >> + goto remove_ida; >> + >> + ret = dev_pm_genpd_performance_state_count(&pd_wdev->dev); >> + if (ret < 0) >> + goto out_genpd; >> + >> + pd_wdev->max_state = ret - 1; >> + pm_runtime_enable(&pd_wdev->dev); >> + pd_wdev->runtime_resumed = false; >> + >> + snprintf(cdev_name, sizeof(cdev_name), "thermal-pd-%d", pd_wdev->id); >> + pd_wdev->cdev = thermal_of_cooling_device_register >> + (NULL, cdev_name, pd_wdev, >> + &pd_warming_device_ops); >> + if (IS_ERR(pd_wdev->cdev)) { >> + pr_err("unable to register %s cooling device\n", cdev_name); >> + ret = PTR_ERR(pd_wdev->cdev); >> + goto out_runtime_disable; >> + } >> + >> + return pd_wdev->cdev; >> + >> +out_runtime_disable: >> + pm_runtime_disable(&pd_wdev->dev); >> +out_genpd: >> + pm_genpd_remove_device(&pd_wdev->dev); >> +remove_ida: >> + ida_simple_remove(&pd_ida, pd_wdev->id); >> +unregister_device: >> + device_unregister(&pd_wdev->dev); >> + pd_warming_release(&pd_wdev->dev); > > This is wrong, drop this. Oops . sorry . Will do. Will fix rest of the comments below as well. > >> +free_pd_wdev: >> + kfree(pd_wdev); > > Since you should free this from the ->release() callback, there is no > need to do this here. > >> + return ERR_PTR(ret); >> +} >> +EXPORT_SYMBOL_GPL(of_pd_warming_register); >> + >> +void pd_warming_unregister(struct thermal_cooling_device *cdev) >> +{ >> + struct pd_warming_device *pd_wdev = cdev->devdata; >> + struct device *dev = &pd_wdev->dev; >> + >> + if (pd_wdev->runtime_resumed) { >> + dev_pm_genpd_set_performance_state(dev, 0); >> + pm_runtime_put(dev); >> + pd_wdev->runtime_resumed = false; >> + } >> + pm_runtime_disable(dev); >> + pm_genpd_remove_device(dev); >> + ida_simple_remove(&pd_ida, pd_wdev->id); >> + thermal_cooling_device_unregister(cdev); >> + kfree(pd_wdev); > > Don't use kfree here, but instead device_unregister(dev); > >> +} >> +EXPORT_SYMBOL_GPL(pd_warming_unregister); >> diff --git a/include/linux/pd_warming.h b/include/linux/pd_warming.h >> new file mode 100644 >> index 000000000000..550a5683b56d >> --- /dev/null >> +++ b/include/linux/pd_warming.h >> @@ -0,0 +1,29 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Copyright (c) 2019, Linaro Ltd. >> + */ >> +#ifndef __PWR_DOMAIN_WARMING_H__ >> +#define __PWR_DOMAIN_WARMING_H__ >> + >> +#include <linux/pm_domain.h> >> +#include <linux/thermal.h> >> + >> +#ifdef CONFIG_PWR_DOMAIN_WARMING_THERMAL >> +struct thermal_cooling_device * >> +of_pd_warming_register(struct device *parent, int pd_id); >> + >> +void pd_warming_unregister(struct thermal_cooling_device *cdev); >> + >> +#else >> +static inline struct thermal_cooling_device * >> +of_pd_warming_register(struct device *parent, int pd_id) >> +{ >> + return ERR_PTR(-ENOSYS); >> +} >> + >> +static inline void >> +pd_warming_unregister(struct thermal_cooling_device *cdev) >> +{ >> +} >> +#endif /* CONFIG_PWR_DOMAIN_WARMING_THERMAL */ >> +#endif /* __PWR_DOMAIN_WARMING_H__ */ >> -- >> 2.20.1 >> > > Besides the few things above, this looks good to me. > > Kind regards > Uffe >
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 4d6753f2b18f..92522d541d0e 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -206,6 +206,16 @@ config DEVFREQ_THERMAL If you want this support, you should say Y here. +config PWR_DOMAIN_WARMING_THERMAL + bool "Power Domain based warming device" + depends on PM_GENERIC_DOMAINS_OF + help + This implements the generic power domain based warming + mechanism through increasing the performance state of + a power domain. + + If you want this support, you should say Y here. + config THERMAL_EMULATION bool "Thermal emulation mode support" help diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 8c8ed7b79915..7db87a779126 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -28,6 +28,8 @@ thermal_sys-$(CONFIG_CLOCK_THERMAL) += clock_cooling.o # devfreq cooling thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o +thermal_sys-$(CONFIG_PWR_DOMAIN_WARMING_THERMAL) += pd_warming.o + # platform thermal drivers obj-y += broadcom/ obj-$(CONFIG_THERMAL_MMIO) += thermal_mmio.o diff --git a/drivers/thermal/pd_warming.c b/drivers/thermal/pd_warming.c new file mode 100644 index 000000000000..c0854d2e4b92 --- /dev/null +++ b/drivers/thermal/pd_warming.c @@ -0,0 +1,168 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2019, Linaro Ltd + */ +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> +#include <linux/pd_warming.h> + +struct pd_warming_device { + struct thermal_cooling_device *cdev; + struct device dev; + int id; + int max_state; + int cur_state; + bool runtime_resumed; +}; + +static DEFINE_IDA(pd_ida); + +static int pd_wdev_get_max_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct pd_warming_device *pd_wdev = cdev->devdata; + + *state = pd_wdev->max_state; + return 0; +} + +static int pd_wdev_get_cur_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct pd_warming_device *pd_wdev = cdev->devdata; + + *state = dev_pm_genpd_get_performance_state(&pd_wdev->dev); + + return 0; +} + +static int pd_wdev_set_cur_state(struct thermal_cooling_device *cdev, + unsigned long state) +{ + struct pd_warming_device *pd_wdev = cdev->devdata; + struct device *dev = &pd_wdev->dev; + int ret; + + ret = dev_pm_genpd_set_performance_state(dev, state); + + if (ret) + return ret; + + if (state && !pd_wdev->runtime_resumed) { + ret = pm_runtime_get_sync(dev); + pd_wdev->runtime_resumed = true; + } else if (!state && pd_wdev->runtime_resumed) { + ret = pm_runtime_put(dev); + pd_wdev->runtime_resumed = false; + } + + return ret; +} + +static struct thermal_cooling_device_ops pd_warming_device_ops = { + .get_max_state = pd_wdev_get_max_state, + .get_cur_state = pd_wdev_get_cur_state, + .set_cur_state = pd_wdev_set_cur_state, +}; + +static void pd_warming_release(struct device *dev) +{ + kfree(dev); +} + +struct thermal_cooling_device * +of_pd_warming_register(struct device *parent, int pd_id) +{ + struct pd_warming_device *pd_wdev; + struct of_phandle_args pd_args; + char cdev_name[THERMAL_NAME_LENGTH]; + int ret; + + pd_wdev = kzalloc(sizeof(*pd_wdev), GFP_KERNEL); + if (!pd_wdev) + return ERR_PTR(-ENOMEM); + + dev_set_name(&pd_wdev->dev, "%s_%d_warming_dev", + dev_name(parent), pd_id); + pd_wdev->dev.parent = parent; + pd_wdev->dev.release = pd_warming_release; + + ret = device_register(&pd_wdev->dev); + if (ret) { + put_device(&pd_wdev->dev); + goto free_pd_wdev; + } + + ret = ida_simple_get(&pd_ida, 0, 0, GFP_KERNEL); + if (ret < 0) + goto unregister_device; + + pd_wdev->id = ret; + + pd_args.np = parent->of_node; + pd_args.args[0] = pd_id; + pd_args.args_count = 1; + + ret = of_genpd_add_device(&pd_args, &pd_wdev->dev); + + if (ret) + goto remove_ida; + + ret = dev_pm_genpd_performance_state_count(&pd_wdev->dev); + if (ret < 0) + goto out_genpd; + + pd_wdev->max_state = ret - 1; + pm_runtime_enable(&pd_wdev->dev); + pd_wdev->runtime_resumed = false; + + snprintf(cdev_name, sizeof(cdev_name), "thermal-pd-%d", pd_wdev->id); + pd_wdev->cdev = thermal_of_cooling_device_register + (NULL, cdev_name, pd_wdev, + &pd_warming_device_ops); + if (IS_ERR(pd_wdev->cdev)) { + pr_err("unable to register %s cooling device\n", cdev_name); + ret = PTR_ERR(pd_wdev->cdev); + goto out_runtime_disable; + } + + return pd_wdev->cdev; + +out_runtime_disable: + pm_runtime_disable(&pd_wdev->dev); +out_genpd: + pm_genpd_remove_device(&pd_wdev->dev); +remove_ida: + ida_simple_remove(&pd_ida, pd_wdev->id); +unregister_device: + device_unregister(&pd_wdev->dev); + pd_warming_release(&pd_wdev->dev); +free_pd_wdev: + kfree(pd_wdev); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(of_pd_warming_register); + +void pd_warming_unregister(struct thermal_cooling_device *cdev) +{ + struct pd_warming_device *pd_wdev = cdev->devdata; + struct device *dev = &pd_wdev->dev; + + if (pd_wdev->runtime_resumed) { + dev_pm_genpd_set_performance_state(dev, 0); + pm_runtime_put(dev); + pd_wdev->runtime_resumed = false; + } + pm_runtime_disable(dev); + pm_genpd_remove_device(dev); + ida_simple_remove(&pd_ida, pd_wdev->id); + thermal_cooling_device_unregister(cdev); + kfree(pd_wdev); +} +EXPORT_SYMBOL_GPL(pd_warming_unregister); diff --git a/include/linux/pd_warming.h b/include/linux/pd_warming.h new file mode 100644 index 000000000000..550a5683b56d --- /dev/null +++ b/include/linux/pd_warming.h @@ -0,0 +1,29 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2019, Linaro Ltd. + */ +#ifndef __PWR_DOMAIN_WARMING_H__ +#define __PWR_DOMAIN_WARMING_H__ + +#include <linux/pm_domain.h> +#include <linux/thermal.h> + +#ifdef CONFIG_PWR_DOMAIN_WARMING_THERMAL +struct thermal_cooling_device * +of_pd_warming_register(struct device *parent, int pd_id); + +void pd_warming_unregister(struct thermal_cooling_device *cdev); + +#else +static inline struct thermal_cooling_device * +of_pd_warming_register(struct device *parent, int pd_id) +{ + return ERR_PTR(-ENOSYS); +} + +static inline void +pd_warming_unregister(struct thermal_cooling_device *cdev) +{ +} +#endif /* CONFIG_PWR_DOMAIN_WARMING_THERMAL */ +#endif /* __PWR_DOMAIN_WARMING_H__ */
Resources modeled as power domains in linux kernel can be used to warm the SoC(eg. mx power domain on sdm845). To support this feature, introduce a generic power domain warming device driver that can be plugged into the thermal framework (The thermal framework itself requires further modifiction to support a warming device in place of a cooling device. Those extensions are not introduced in this patch series). Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org> --- v3->v4: - Removed late_init hook pd_warming_device_ops. - Use of_genpd_add_device instead of pm_genpd_add_device to attach device to the generic power domain. - Use thermal_of_cooling_device_parent_register to register the cooling device so that the device with genpd attached can be made parent of the cooling device. - With above changes, remove reference to generic_pm_domain in pd_warming_device. v4->v5: - All the below changes are as per Ulf's review comments. - Renamed pwr_domain_warming.c and pwr_domain_warming.h to pd_warming.c and pd_warming.h. - Renamed pwr_domain_warming_register API to of_pd_warming_register. - Dropped in-param pd_name to of_pd_warming_register. - Introduced ID allocator to uniquely identify each power domain warming device. - Introduced pd_warming_release to handle device kfree for pd_warming_device. - Introduced pm_genpd_remove_device in the error exit path of of_pd_warming_register. drivers/thermal/Kconfig | 10 +++ drivers/thermal/Makefile | 2 + drivers/thermal/pd_warming.c | 168 +++++++++++++++++++++++++++++++++++ include/linux/pd_warming.h | 29 ++++++ 4 files changed, 209 insertions(+) create mode 100644 drivers/thermal/pd_warming.c create mode 100644 include/linux/pd_warming.h