diff --git a/drivers/reset/core.c b/drivers/reset/core.c index 0090784ff410..c8fb4426b218 100644 --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -43,10 +43,23 @@ struct reset_control { unsigned int id; struct kref refcnt; bool shared; + bool array; atomic_t deassert_count; atomic_t triggered_count; }; +/** + * struct reset_control_array - an array of reset controls + * @base: reset control for compatibility with reset control API functions + * @num_rstcs: number of reset controls + * @rstc: array of reset controls + */ +struct reset_control_array { + struct reset_control base; + unsigned int num_rstcs; + struct reset_control *rstc[]; +}; + /** * of_reset_simple_xlate - translate reset_spec to the reset line number * @rcdev: a pointer to the reset controller device @@ -135,6 +148,65 @@ int devm_reset_controller_register(struct device *dev, } EXPORT_SYMBOL_GPL(devm_reset_controller_register); +static inline struct reset_control_array * +rstc_to_array(struct reset_control *rstc) { + return container_of(rstc, struct reset_control_array, base); +} + +static int reset_control_array_reset(struct reset_control_array *resets) +{ + int ret, i; + + for (i = 0; i < resets->num_rstcs; i++) { + ret = reset_control_reset(resets->rstc[i]); + if (ret) + return ret; + } + + return 0; +} + +static int reset_control_array_assert(struct reset_control_array *resets) +{ + int ret, i; + + for (i = 0; i < resets->num_rstcs; i++) { + ret = reset_control_assert(resets->rstc[i]); + if (ret) + goto err; + } + + return 0; + +err: + while (i--) + reset_control_deassert(resets->rstc[i]); + return ret; +} + +static int reset_control_array_deassert(struct reset_control_array *resets) +{ + int ret, i; + + for (i = 0; i < resets->num_rstcs; i++) { + ret = reset_control_deassert(resets->rstc[i]); + if (ret) + goto err; + } + + return 0; + +err: + while (i--) + reset_control_assert(resets->rstc[i]); + return ret; +} + +static inline bool reset_control_is_array(struct reset_control *rstc) +{ + return rstc->array; +} + /** * reset_control_reset - reset the controlled device * @rstc: reset controller @@ -158,6 +230,9 @@ int reset_control_reset(struct reset_control *rstc) if (WARN_ON(IS_ERR(rstc))) return -EINVAL; + if (reset_control_is_array(rstc)) + return reset_control_array_reset(rstc_to_array(rstc)); + if (!rstc->rcdev->ops->reset) return -ENOTSUPP; @@ -202,6 +277,9 @@ int reset_control_assert(struct reset_control *rstc) if (WARN_ON(IS_ERR(rstc))) return -EINVAL; + if (reset_control_is_array(rstc)) + return reset_control_array_assert(rstc_to_array(rstc)); + if (!rstc->rcdev->ops->assert) return -ENOTSUPP; @@ -240,6 +318,9 @@ int reset_control_deassert(struct reset_control *rstc) if (WARN_ON(IS_ERR(rstc))) return -EINVAL; + if (reset_control_is_array(rstc)) + return reset_control_array_deassert(rstc_to_array(rstc)); + if (!rstc->rcdev->ops->deassert) return -ENOTSUPP; @@ -266,7 +347,7 @@ int reset_control_status(struct reset_control *rstc) if (!rstc) return 0; - if (WARN_ON(IS_ERR(rstc))) + if (WARN_ON(IS_ERR(rstc)) || reset_control_is_array(rstc)) return -EINVAL; if (rstc->rcdev->ops->status) @@ -404,6 +485,16 @@ struct reset_control *__reset_control_get(struct device *dev, const char *id, } EXPORT_SYMBOL_GPL(__reset_control_get); +static void reset_control_array_put(struct reset_control_array *resets) +{ + int i; + + mutex_lock(&reset_list_mutex); + for (i = 0; i < resets->num_rstcs; i++) + __reset_control_put_internal(resets->rstc[i]); + mutex_unlock(&reset_list_mutex); +} + /** * reset_control_put - free the reset controller * @rstc: reset controller @@ -413,6 +504,11 @@ void reset_control_put(struct reset_control *rstc) if (IS_ERR_OR_NULL(rstc)) return; + if (reset_control_is_array(rstc)) { + reset_control_array_put(rstc_to_array(rstc)); + return; + } + mutex_lock(&reset_list_mutex); __reset_control_put_internal(rstc); mutex_unlock(&reset_list_mutex); @@ -472,3 +568,116 @@ int device_reset(struct device *dev) return ret; } EXPORT_SYMBOL_GPL(device_reset); + +/** + * APIs to manage an array of reset controls. + */ +/** + * of_reset_control_get_count - Count number of resets available with a device + * + * @node: device node that contains 'resets'. + * + * Returns positive reset count on success, or error number on failure and + * on count being zero. + */ +static int of_reset_control_get_count(struct device_node *node) +{ + int count; + + if (!node) + return -EINVAL; + + count = of_count_phandle_with_args(node, "resets", "#reset-cells"); + if (count == 0) + count = -ENOENT; + + return count; +} + +/** + * of_reset_control_array_get - Get a list of reset controls using + * device node. + * + * @np: device node for the device that requests the reset controls array + * @shared: whether reset controls are shared or not + * @optional: whether it is optional to get the reset controls + * + * Returns pointer to allocated reset_control_array on success or + * error on failure + */ +struct reset_control * +of_reset_control_array_get(struct device_node *np, bool shared, bool optional) +{ + struct reset_control_array *resets; + struct reset_control *rstc; + int num, i; + + num = of_reset_control_get_count(np); + if (num < 0) + return optional ? NULL : ERR_PTR(num); + + resets = kzalloc(sizeof(*resets) + sizeof(resets->rstc[0]) * num, + GFP_KERNEL); + if (!resets) + return ERR_PTR(-ENOMEM); + + for (i = 0; i < num; i++) { + rstc = __of_reset_control_get(np, NULL, i, shared, optional); + if (IS_ERR(rstc)) + goto err_rst; + resets->rstc[i] = rstc; + } + resets->num_rstcs = num; + resets->base.array = true; + + return &resets->base; + +err_rst: + mutex_lock(&reset_list_mutex); + while (--i >= 0) + __reset_control_put_internal(resets->rstc[i]); + mutex_unlock(&reset_list_mutex); + + kfree(resets); + + return rstc; +} +EXPORT_SYMBOL_GPL(of_reset_control_array_get); + +/** + * devm_reset_control_array_get - Resource managed reset control array get + * + * @dev: device that requests the list of reset controls + * @shared: whether reset controls are shared or not + * @optional: whether it is optional to get the reset controls + * + * The reset control array APIs are intended for a list of resets + * that just have to be asserted or deasserted, without any + * requirements on the order. + * + * Returns pointer to allocated reset_control_array on success or + * error on failure + */ +struct reset_control * +devm_reset_control_array_get(struct device *dev, bool shared, bool optional) +{ + struct reset_control **devres; + struct reset_control *rstc; + + devres = devres_alloc(devm_reset_control_release, sizeof(*devres), + GFP_KERNEL); + if (!devres) + return ERR_PTR(-ENOMEM); + + rstc = of_reset_control_array_get(dev->of_node, shared, optional); + if (IS_ERR(rstc)) { + devres_free(devres); + return rstc; + } + + *devres = rstc; + devres_add(dev, devres); + + return rstc; +} +EXPORT_SYMBOL_GPL(devm_reset_control_array_get); diff --git a/include/linux/reset.h b/include/linux/reset.h index 13d8681210d5..56463f37f3e6 100644 --- a/include/linux/reset.h +++ b/include/linux/reset.h @@ -25,6 +25,11 @@ struct reset_control *__devm_reset_control_get(struct device *dev, int __must_check device_reset(struct device *dev); +struct reset_control *devm_reset_control_array_get(struct device *dev, + bool shared, bool optional); +struct reset_control *of_reset_control_array_get(struct device_node *np, + bool shared, bool optional); + static inline int device_reset_optional(struct device *dev) { return device_reset(dev); @@ -89,6 +94,18 @@ static inline struct reset_control *__devm_reset_control_get( return optional ? NULL : ERR_PTR(-ENOTSUPP); } +static inline struct reset_control * +devm_reset_control_array_get(struct device *dev, bool shared, bool optional) +{ + return optional ? NULL : ERR_PTR(-ENOTSUPP); +} + +static inline struct reset_control * +of_reset_control_array_get(struct device_node *np, bool shared, bool optional) +{ + return optional ? NULL : ERR_PTR(-ENOTSUPP); +} + #endif /* CONFIG_RESET_CONTROLLER */ /** @@ -374,4 +391,55 @@ static inline struct reset_control *devm_reset_control_get_by_index( { return devm_reset_control_get_exclusive_by_index(dev, index); } + +/* + * APIs to manage a list of reset controllers + */ +static inline struct reset_control * +devm_reset_control_array_get_exclusive(struct device *dev) +{ + return devm_reset_control_array_get(dev, false, false); +} + +static inline struct reset_control * +devm_reset_control_array_get_shared(struct device *dev) +{ + return devm_reset_control_array_get(dev, true, false); +} + +static inline struct reset_control * +devm_reset_control_array_get_optional_exclusive(struct device *dev) +{ + return devm_reset_control_array_get(dev, false, true); +} + +static inline struct reset_control * +devm_reset_control_array_get_optional_shared(struct device *dev) +{ + return devm_reset_control_array_get(dev, true, true); +} + +static inline struct reset_control * +of_reset_control_array_get_exclusive(struct device_node *node) +{ + return of_reset_control_array_get(node, false, false); +} + +static inline struct reset_control * +of_reset_control_array_get_shared(struct device_node *node) +{ + return of_reset_control_array_get(node, true, false); +} + +static inline struct reset_control * +of_reset_control_array_get_optional_exclusive(struct device_node *node) +{ + return of_reset_control_array_get(node, false, true); +} + +static inline struct reset_control * +of_reset_control_array_get_optional_shared(struct device_node *node) +{ + return of_reset_control_array_get(node, true, true); +} #endif