Basing on MMC's pwrseq support code, add separate power sequencer subsystem. It will be used by other drivers to handle device power up requirements. Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> --- drivers/power/Kconfig | 1 + drivers/power/Makefile | 1 + drivers/power/pwrseq/Kconfig | 11 + drivers/power/pwrseq/Makefile | 6 + drivers/power/pwrseq/core.c | 412 ++++++++++++++++++++++++++++++++ include/linux/pwrseq/consumer.h | 88 +++++++ include/linux/pwrseq/driver.h | 75 ++++++ 7 files changed, 594 insertions(+) create mode 100644 drivers/power/pwrseq/Kconfig create mode 100644 drivers/power/pwrseq/Makefile create mode 100644 drivers/power/pwrseq/core.c create mode 100644 include/linux/pwrseq/consumer.h create mode 100644 include/linux/pwrseq/driver.h diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig index 696bf77a7042..c87cd2240a74 100644 --- a/drivers/power/Kconfig +++ b/drivers/power/Kconfig @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only +source "drivers/power/pwrseq/Kconfig" source "drivers/power/reset/Kconfig" source "drivers/power/supply/Kconfig" diff --git a/drivers/power/Makefile b/drivers/power/Makefile index effbf0377f32..1dbce454a8c4 100644 --- a/drivers/power/Makefile +++ b/drivers/power/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only obj-$(CONFIG_POWER_RESET) += reset/ obj-$(CONFIG_POWER_SUPPLY) += supply/ +obj-$(CONFIG_PWRSEQ) += pwrseq/ diff --git a/drivers/power/pwrseq/Kconfig b/drivers/power/pwrseq/Kconfig new file mode 100644 index 000000000000..8904ec9ed541 --- /dev/null +++ b/drivers/power/pwrseq/Kconfig @@ -0,0 +1,11 @@ +# SPDX-License-Identifier: GPL-2.0-only +menuconfig PWRSEQ + bool "Power Sequencer drivers" + help + Provides support for special power sequencing drivers. + + Say Y here to enable support for such devices + +if PWRSEQ + +endif diff --git a/drivers/power/pwrseq/Makefile b/drivers/power/pwrseq/Makefile new file mode 100644 index 000000000000..108429ff6445 --- /dev/null +++ b/drivers/power/pwrseq/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for power sequencer drivers. +# + +obj-$(CONFIG_PWRSEQ) += core.o diff --git a/drivers/power/pwrseq/core.c b/drivers/power/pwrseq/core.c new file mode 100644 index 000000000000..2e4e9d123e60 --- /dev/null +++ b/drivers/power/pwrseq/core.c @@ -0,0 +1,412 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2021 (c) Linaro Ltd. + * Author: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> + * + * Based on phy-core.c: + * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com + */ + +#include <linux/device.h> +#include <linux/idr.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/pm_runtime.h> +#include <linux/pwrseq/consumer.h> +#include <linux/pwrseq/driver.h> +#include <linux/slab.h> + +#define to_pwrseq(a) (container_of((a), struct pwrseq, dev)) + +static DEFINE_IDA(pwrseq_ida); +static DEFINE_MUTEX(pwrseq_provider_mutex); +static LIST_HEAD(pwrseq_provider_list); + +struct pwrseq_provider { + struct device *dev; + struct module *owner; + struct list_head list; + void *data; + struct pwrseq * (*of_xlate)(void *data, struct of_phandle_args *args); +}; + +void pwrseq_put(struct device *dev, struct pwrseq *pwrseq) +{ + device_link_remove(dev, &pwrseq->dev); + + module_put(pwrseq->owner); + put_device(&pwrseq->dev); +} +EXPORT_SYMBOL_GPL(pwrseq_put); + +static struct pwrseq_provider *of_pwrseq_provider_lookup(struct device_node *node) +{ + struct pwrseq_provider *pwrseq_provider; + + list_for_each_entry(pwrseq_provider, &pwrseq_provider_list, list) { + if (pwrseq_provider->dev->of_node == node) + return pwrseq_provider; + } + + return ERR_PTR(-EPROBE_DEFER); +} + +static struct pwrseq *_of_pwrseq_get(struct device *dev, const char *id) +{ + struct pwrseq_provider *pwrseq_provider; + struct pwrseq *pwrseq; + struct of_phandle_args args; + char prop_name[64]; /* 64 is max size of property name */ + int ret; + + snprintf(prop_name, 64, "%s-pwrseq", id); + ret = of_parse_phandle_with_args(dev->of_node, prop_name, "#pwrseq-cells", 0, &args); + if (ret) { + /* + * Parsing failed. Try locating old bindings for mmc-pwrseq, + * which did not use #pwrseq-cells. + */ + if (strcmp(id, "mmc")) + return NULL; + + ret = of_parse_phandle_with_args(dev->of_node, prop_name, NULL, 0, &args); + if (ret) + return NULL; + + dev_warn(dev, "old mmc-pwrseq binding used, add #pwrseq-cells to the provider\n"); + } + + mutex_lock(&pwrseq_provider_mutex); + pwrseq_provider = of_pwrseq_provider_lookup(args.np); + if (IS_ERR(pwrseq_provider) || !try_module_get(pwrseq_provider->owner)) { + pwrseq = ERR_PTR(-EPROBE_DEFER); + goto out_unlock; + } + + if (!of_device_is_available(args.np)) { + dev_warn(pwrseq_provider->dev, "Requested pwrseq is disabled\n"); + pwrseq = ERR_PTR(-ENODEV); + goto out_put_module; + } + + pwrseq = pwrseq_provider->of_xlate(pwrseq_provider->data, &args); + +out_put_module: + module_put(pwrseq_provider->owner); + +out_unlock: + mutex_unlock(&pwrseq_provider_mutex); + of_node_put(args.np); + + return pwrseq; +} + +struct pwrseq * __pwrseq_get(struct device *dev, const char *id, bool optional) +{ + struct pwrseq *pwrseq; + struct device_link *link; + + pwrseq = _of_pwrseq_get(dev, id); + if (pwrseq == NULL) + return optional ? NULL : ERR_PTR(-ENODEV); + else if (IS_ERR(pwrseq)) + return pwrseq; + + if (!try_module_get(pwrseq->owner)) + return ERR_PTR(-EPROBE_DEFER); + + get_device(&pwrseq->dev); + link = device_link_add(dev, &pwrseq->dev, DL_FLAG_STATELESS); + if (!link) + dev_dbg(dev, "failed to create device link to %s\n", + dev_name(pwrseq->dev.parent)); + + return pwrseq; +} + +struct pwrseq * pwrseq_get(struct device *dev, const char *id) +{ + return __pwrseq_get(dev, id, false); +} +EXPORT_SYMBOL_GPL(pwrseq_get); + +static void devm_pwrseq_release(struct device *dev, void *res) +{ + struct pwrseq *pwrseq = *(struct pwrseq **)res; + + pwrseq_put(dev, pwrseq); +} + +struct pwrseq * devm_pwrseq_get(struct device *dev, const char *id) +{ + struct pwrseq **ptr, *pwrseq; + + ptr = devres_alloc(devm_pwrseq_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + pwrseq = pwrseq_get(dev, id); + if (!IS_ERR(pwrseq)) { + *ptr = pwrseq; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return pwrseq; +} +EXPORT_SYMBOL_GPL(devm_pwrseq_get); + +struct pwrseq * pwrseq_get_optional(struct device *dev, const char *id) +{ + return __pwrseq_get(dev, id, true); +} +EXPORT_SYMBOL_GPL(pwrseq_get_optional); + +struct pwrseq * devm_pwrseq_get_optional(struct device *dev, const char *id) +{ + struct pwrseq **ptr, *pwrseq; + + ptr = devres_alloc(devm_pwrseq_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + pwrseq = pwrseq_get_optional(dev, id); + if (!IS_ERR_OR_NULL(pwrseq)) { + *ptr = pwrseq; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return pwrseq; +} +EXPORT_SYMBOL_GPL(devm_pwrseq_get_optional); + +int pwrseq_pre_power_on(struct pwrseq *pwrseq) +{ + if (pwrseq && pwrseq->ops->pre_power_on) + return pwrseq->ops->pre_power_on(pwrseq); + + return 0; +} +EXPORT_SYMBOL_GPL(pwrseq_pre_power_on); + +int pwrseq_power_on(struct pwrseq *pwrseq) +{ + if (pwrseq && pwrseq->ops->power_on) + return pwrseq->ops->power_on(pwrseq); + + return 0; +} +EXPORT_SYMBOL_GPL(pwrseq_power_on); + +void pwrseq_power_off(struct pwrseq *pwrseq) +{ + if (pwrseq && pwrseq->ops->power_off) + pwrseq->ops->power_off(pwrseq); +} +EXPORT_SYMBOL_GPL(pwrseq_power_off); + +void pwrseq_reset(struct pwrseq *pwrseq) +{ + if (pwrseq && pwrseq->ops->reset) + pwrseq->ops->reset(pwrseq); +} +EXPORT_SYMBOL_GPL(pwrseq_reset); + +static void pwrseq_dev_release(struct device *dev) +{ + struct pwrseq *pwrseq = to_pwrseq(dev); + + ida_free(&pwrseq_ida, pwrseq->id); + of_node_put(dev->of_node); + kfree(pwrseq); +} + +static struct class pwrseq_class = { + .name = "pwrseq", + .dev_release = pwrseq_dev_release, +}; + +struct pwrseq *__pwrseq_create(struct device *dev, struct module *owner, const struct pwrseq_ops *ops, void *data) +{ + struct pwrseq *pwrseq; + int ret; + + if (WARN_ON(!dev)) + return ERR_PTR(-EINVAL); + + pwrseq = kzalloc(sizeof(*pwrseq), GFP_KERNEL); + if (!pwrseq) + return ERR_PTR(-ENOMEM); + + ret = ida_alloc(&pwrseq_ida, GFP_KERNEL); + if (ret < 0) + goto free_pwrseq; + + pwrseq->id = ret; + + device_initialize(&pwrseq->dev); + + pwrseq->dev.class = &pwrseq_class; + pwrseq->dev.parent = dev; + pwrseq->dev.of_node = of_node_get(dev->of_node); + pwrseq->ops = ops; + pwrseq->owner = owner; + + dev_set_drvdata(&pwrseq->dev, data); + + ret = dev_set_name(&pwrseq->dev, "pwrseq-%s.%u", dev_name(dev), pwrseq->id); + if (ret) + goto put_dev; + + ret = device_add(&pwrseq->dev); + if (ret) + goto put_dev; + + if (pm_runtime_enabled(dev)) { + pm_runtime_enable(&pwrseq->dev); + pm_runtime_no_callbacks(&pwrseq->dev); + } + + return pwrseq; + +put_dev: + /* will call pwrseq_dev_release() to free resources */ + put_device(&pwrseq->dev); + + return ERR_PTR(ret); + +free_pwrseq: + kfree(pwrseq); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(__pwrseq_create); + +void pwrseq_destroy(struct pwrseq *pwrseq) +{ + pm_runtime_disable(&pwrseq->dev); + device_unregister(&pwrseq->dev); +} +EXPORT_SYMBOL_GPL(pwrseq_destroy); + +static void devm_pwrseq_destroy(struct device *dev, void *res) +{ + struct pwrseq *pwrseq = *(struct pwrseq **)res; + + pwrseq_destroy(pwrseq); +} + +struct pwrseq *__devm_pwrseq_create(struct device *dev, struct module *owner, const struct pwrseq_ops *ops, void *data) +{ + struct pwrseq **ptr, *pwrseq; + + ptr = devres_alloc(devm_pwrseq_destroy, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + pwrseq = __pwrseq_create(dev, owner, ops, data); + if (!IS_ERR(pwrseq)) { + *ptr = pwrseq; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return pwrseq; +} +EXPORT_SYMBOL_GPL(__devm_pwrseq_create); + +struct pwrseq_provider *__of_pwrseq_provider_register(struct device *dev, + struct module *owner, + struct pwrseq * (*of_xlate)(void *data, + struct of_phandle_args *args), + void *data) +{ + struct pwrseq_provider *pwrseq_provider; + + pwrseq_provider = kzalloc(sizeof(*pwrseq_provider), GFP_KERNEL); + if (!pwrseq_provider) + return ERR_PTR(-ENOMEM); + + pwrseq_provider->dev = dev; + pwrseq_provider->owner = owner; + pwrseq_provider->of_xlate = of_xlate; + pwrseq_provider->data = data; + + mutex_lock(&pwrseq_provider_mutex); + list_add_tail(&pwrseq_provider->list, &pwrseq_provider_list); + mutex_unlock(&pwrseq_provider_mutex); + + return pwrseq_provider; +} +EXPORT_SYMBOL_GPL(__of_pwrseq_provider_register); + +void of_pwrseq_provider_unregister(struct pwrseq_provider *pwrseq_provider) +{ + if (IS_ERR(pwrseq_provider)) + return; + + mutex_lock(&pwrseq_provider_mutex); + list_del(&pwrseq_provider->list); + kfree(pwrseq_provider); + mutex_unlock(&pwrseq_provider_mutex); +} +EXPORT_SYMBOL_GPL(of_pwrseq_provider_unregister); + +static void devm_pwrseq_provider_unregister(struct device *dev, void *res) +{ + struct pwrseq_provider *pwrseq_provider = *(struct pwrseq_provider **)res; + + of_pwrseq_provider_unregister(pwrseq_provider); +} + +struct pwrseq_provider *__devm_of_pwrseq_provider_register(struct device *dev, + struct module *owner, + struct pwrseq * (*of_xlate)(void *data, + struct of_phandle_args *args), + void *data) +{ + struct pwrseq_provider **ptr, *pwrseq_provider; + + ptr = devres_alloc(devm_pwrseq_provider_unregister, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + pwrseq_provider = __of_pwrseq_provider_register(dev, owner, of_xlate, data); + if (!IS_ERR(pwrseq_provider)) { + *ptr = pwrseq_provider; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return pwrseq_provider; +} +EXPORT_SYMBOL_GPL(__devm_of_pwrseq_provider_register); + +struct pwrseq *of_pwrseq_xlate_onecell(void *data, struct of_phandle_args *args) +{ + struct pwrseq_onecell_data *pwrseq_data = data; + unsigned int idx; + + if (args->args_count != 1) + return ERR_PTR(-EINVAL); + + idx = args->args[0]; + if (idx >= pwrseq_data->num) { + pr_err("%s: invalid index %u\n", __func__, idx); + return ERR_PTR(-EINVAL); + } + + return pwrseq_data->pwrseqs[idx]; +} + +static int __init pwrseq_core_init(void) +{ + return class_register(&pwrseq_class); +} +device_initcall(pwrseq_core_init); diff --git a/include/linux/pwrseq/consumer.h b/include/linux/pwrseq/consumer.h new file mode 100644 index 000000000000..fbcdc1fc0751 --- /dev/null +++ b/include/linux/pwrseq/consumer.h @@ -0,0 +1,88 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (c) 2021 Linaro Ltd. + */ + +#ifndef __LINUX_PWRSEQ_CONSUMER_H__ +#define __LINUX_PWRSEQ_CONSUMER_H__ + +struct pwrseq; +struct device; + +#if defined(CONFIG_PWRSEQ) + +struct pwrseq *__must_check pwrseq_get(struct device *dev, const char *id); +struct pwrseq *__must_check devm_pwrseq_get(struct device *dev, const char *id); + +struct pwrseq *__must_check pwrseq_get_optional(struct device *dev, const char *id); +struct pwrseq *__must_check devm_pwrseq_get_optional(struct device *dev, const char *id); + +void pwrseq_put(struct device *dev, struct pwrseq *pwrseq); + +int pwrseq_pre_power_on(struct pwrseq *pwrseq); +int pwrseq_power_on(struct pwrseq *pwrseq); +void pwrseq_power_off(struct pwrseq *pwrseq); +void pwrseq_reset(struct pwrseq *pwrseq); + +#else + +static inline struct pwrseq *__must_check +pwrseq_get(struct device *dev, const char *id) +{ + return ERR_PTR(-ENOSYS); +} + +static inline struct pwrseq *__must_check +devm_pwrseq_get(struct device *dev, const char *id) +{ + return ERR_PTR(-ENOSYS); +} + +static inline struct pwrseq *__must_check +pwrseq_get_optional(struct device *dev, const char *id) +{ + return NULL; +} + +static inline struct pwrseq *__must_check +devm_pwrseq_get_optional(struct device *dev, const char *id) +{ + return NULL; +} + +static inline void pwrseq_put(struct device *dev, struct pwrseq *pwrseq) +{ +} + +static inline int pwrseq_pre_power_on(struct pwrseq *pwrseq) +{ + return -ENOSYS; +} + +static inline int pwrseq_power_on(struct pwrseq *pwrseq) +{ + return -ENOSYS; +} + +static inline void pwrseq_power_off(struct pwrseq *pwrseq) +{ +} + +static inline void pwrseq_reset(struct pwrseq *pwrseq) +{ +} + +#endif + +static inline int pwrseq_full_power_on(struct pwrseq *pwrseq) +{ + int ret; + + ret = pwrseq_pre_power_on(pwrseq); + if (ret) + return ret; + + return pwrseq_power_on(pwrseq); +} + +#endif /* __LINUX_PWRSEQ_CONSUMER_H__ */ diff --git a/include/linux/pwrseq/driver.h b/include/linux/pwrseq/driver.h new file mode 100644 index 000000000000..b2bc46624d7e --- /dev/null +++ b/include/linux/pwrseq/driver.h @@ -0,0 +1,75 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (c) 2021 Linaro Ltd. + */ + +#ifndef __LINUX_PWRSEQ_DRIVER_H__ +#define __LINUX_PWRSEQ_DRIVER_H__ + +#include <linux/device.h> + +struct pwrseq; + +struct pwrseq_ops { + int (*pre_power_on)(struct pwrseq *pwrseq); + int (*power_on)(struct pwrseq *pwrseq); + void (*power_off)(struct pwrseq *pwrseq); + void (*reset)(struct pwrseq *pwrseq); +}; + +struct module; + +struct pwrseq { + struct device dev; + const struct pwrseq_ops *ops; + unsigned int id; + struct module *owner; +}; + +struct pwrseq *__pwrseq_create(struct device *dev, struct module *owner, const struct pwrseq_ops *ops, void *data); +struct pwrseq *__devm_pwrseq_create(struct device *dev, struct module *owner, const struct pwrseq_ops *ops, void *data); + +#define pwrseq_create(dev, ops, data) __pwrseq_create((dev), THIS_MODULE, (ops), (data)) +#define devm_pwrseq_create(dev, ops, data) __devm_pwrseq_create((dev), THIS_MODULE, (ops), (data)) + +void pwrseq_destroy(struct pwrseq *pwrseq); + +static inline void *pwrseq_get_data(struct pwrseq *pwrseq) +{ + return dev_get_drvdata(&pwrseq->dev); +} + +#define of_pwrseq_provider_register(dev, xlate, data) \ + __of_pwrseq_provider_register((dev), THIS_MODULE, (xlate), (data)) + +#define devm_of_pwrseq_provider_register(dev, xlate, data) \ + __devm_of_pwrseq_provider_register((dev), THIS_MODULE, (xlate), (data)) + +struct of_phandle_args; + +struct pwrseq_provider *__of_pwrseq_provider_register(struct device *dev, + struct module *owner, + struct pwrseq * (*of_xlate)(void *data, + struct of_phandle_args *args), + void *data); +struct pwrseq_provider *__devm_of_pwrseq_provider_register(struct device *dev, + struct module *owner, + struct pwrseq * (*of_xlate)(void *data, + struct of_phandle_args *args), + void *data); +void of_pwrseq_provider_unregister(struct pwrseq_provider *pwrseq_provider); + +static inline struct pwrseq *of_pwrseq_xlate_single(void *data, + struct of_phandle_args *args) +{ + return data; +} + +struct pwrseq_onecell_data { + unsigned int num; + struct pwrseq *pwrseqs[]; +}; + +struct pwrseq *of_pwrseq_xlate_onecell(void *data, struct of_phandle_args *args); + +#endif /* __LINUX_PWRSEQ_DRIVER_H__ */ -- 2.33.0