Many devices may want to request a bunch of resets and control them. So it's better to manage them as an array. Add APIs to _get(), _assert(), and _deassert() an array of reset_control. Note that, these APIs don't guarantee that the reset lines managed in the array are handled in any particular order. Cc: Felipe Balbi <balbi@xxxxxxxxxx> Cc: Jon Hunter <jonathanh@xxxxxxxxxx> Cc: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx> --- drivers/reset/core.c | 204 ++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/reset.h | 93 +++++++++++++++++++++++ 2 files changed, 297 insertions(+) diff --git a/drivers/reset/core.c b/drivers/reset/core.c index cd739d2fa160..dfb782f862e0 100644 --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -465,3 +465,207 @@ 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; +} + +/** + * reset_control_array_assert: assert a list of resets + * + * @resets: reset control array holding info about the list of resets + * + * This API doesn't guarantee that the reset lines controlled by + * the reset array are asserted in any particular order. + * + * Returns 0 on success or error number on failure. + */ +int reset_control_array_assert(struct reset_control_array *resets) +{ + int ret, i; + + if (!resets) + return 0; + + if (IS_ERR(resets)) + return -EINVAL; + + 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; +} +EXPORT_SYMBOL_GPL(reset_control_array_assert); + +/** + * reset_control_array_deassert: deassert a list of resets + * + * @resets: reset control array holding info about the list of resets + * + * This API doesn't guarantee that the reset lines controlled by + * the reset array are deasserted in any particular order. + * + * Returns 0 on success or error number on failure. + */ +int reset_control_array_deassert(struct reset_control_array *resets) +{ + int ret, i; + + if (!resets) + return 0; + + if (IS_ERR(resets)) + return -EINVAL; + + 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; +} +EXPORT_SYMBOL_GPL(reset_control_array_deassert); + +static void devm_reset_control_array_release(struct device *dev, void *res) +{ + struct reset_control_array *resets = res; + + reset_control_array_put(resets); +} + +/** + * 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_array * +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; + void *err; + + 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)) { + err = ERR_CAST(rstc); + goto err_rst; + } + resets->rstc[i] = rstc; + } + resets->num_rstcs = num; + + return resets; + +err_rst: + while (--i >= 0) + reset_control_put(resets->rstc[i]); + + kfree(resets); + + return err; +} +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_array * +devm_reset_control_array_get(struct device *dev, bool shared, bool optional) +{ + struct reset_control_array **devres; + struct reset_control_array *resets; + + devres = devres_alloc(devm_reset_control_array_release, + sizeof(*devres), GFP_KERNEL); + if (!devres) + return ERR_PTR(-ENOMEM); + + resets = of_reset_control_array_get(dev->of_node, shared, optional); + if (IS_ERR(resets)) { + devres_free(resets); + return resets; + } + + *devres = resets; + devres_add(dev, devres); + + return resets; +} +EXPORT_SYMBOL_GPL(devm_reset_control_array_get); + +void reset_control_array_put(struct reset_control_array *resets) +{ + int i; + + if (IS_ERR_OR_NULL(resets)) + return; + + for (i = 0; i < resets->num_rstcs; i++) + reset_control_put(resets->rstc[i]); + + kfree(resets); +} +EXPORT_SYMBOL_GPL(reset_control_array_put); diff --git a/include/linux/reset.h b/include/linux/reset.h index 13d8681210d5..df75fe50f765 100644 --- a/include/linux/reset.h +++ b/include/linux/reset.h @@ -5,6 +5,11 @@ struct reset_control; +struct reset_control_array { + unsigned int num_rstcs; + struct reset_control *rstc[]; +}; + #ifdef CONFIG_RESET_CONTROLLER int reset_control_reset(struct reset_control *rstc); @@ -25,6 +30,14 @@ struct reset_control *__devm_reset_control_get(struct device *dev, int __must_check device_reset(struct device *dev); +int reset_control_array_assert(struct reset_control_array *resets); +int reset_control_array_deassert(struct reset_control_array *resets); +struct reset_control_array *devm_reset_control_array_get(struct device *dev, + bool shared, bool optional); +struct reset_control_array *of_reset_control_array_get(struct device_node *np, + bool shared, bool optional); +void reset_control_array_put(struct reset_control_array *resets); + static inline int device_reset_optional(struct device *dev) { return device_reset(dev); @@ -89,6 +102,35 @@ static inline struct reset_control *__devm_reset_control_get( return optional ? NULL : ERR_PTR(-ENOTSUPP); } +static inline +int reset_control_array_assert(struct reset_control_array *resets) +{ + return 0; +} + +static inline +int reset_control_array_deassert(struct reset_control_array *resets) +{ + return 0; +} + +static inline struct reset_control_array * +devm_reset_control_array_get(struct device *dev, bool shared, bool optional) +{ + return optional ? NULL : ERR_PTR(-ENOTSUPP); +} + +static inline struct reset_control_array * +of_reset_control_array_get(struct device_node *np, bool shared, bool optional) +{ + return optional ? NULL : ERR_PTR(-ENOTSUPP); +} + +static inline +void reset_control_array_put(struct reset_control_array *resets) +{ +} + #endif /* CONFIG_RESET_CONTROLLER */ /** @@ -374,4 +416,55 @@ 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_array * +devm_reset_control_array_get_exclusive(struct device *dev) +{ + return devm_reset_control_array_get(dev, false, false); +} + +static inline struct reset_control_array * +devm_reset_control_array_get_shared(struct device *dev) +{ + return devm_reset_control_array_get(dev, true, false); +} + +static inline struct reset_control_array * +devm_reset_control_array_get_optional_exclusive(struct device *dev) +{ + return devm_reset_control_array_get(dev, false, true); +} + +static inline struct reset_control_array * +devm_reset_control_array_get_optional_shared(struct device *dev) +{ + return devm_reset_control_array_get(dev, true, true); +} + +static inline struct reset_control_array * +of_reset_control_array_get_exclusive(struct device_node *node) +{ + return of_reset_control_array_get(node, false, false); +} + +static inline struct reset_control_array * +of_reset_control_array_get_shared(struct device_node *node) +{ + return of_reset_control_array_get(node, true, false); +} + +static inline struct reset_control_array * +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_array * +of_reset_control_array_get_optional_shared(struct device_node *node) +{ + return of_reset_control_array_get(node, true, true); +} #endif -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html