diff options
-rw-r--r-- | drivers/iio/Kconfig | 8 | ||||
-rw-r--r-- | drivers/iio/Makefile | 1 | ||||
-rw-r--r-- | drivers/iio/industrialio-sw-trigger.c | 183 | ||||
-rw-r--r-- | include/linux/iio/sw_trigger.h | 71 |
4 files changed, 263 insertions, 0 deletions
diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig index 9509b8a4c551..ac8715e56ba1 100644 --- a/drivers/iio/Kconfig +++ b/drivers/iio/Kconfig @@ -46,6 +46,14 @@ config IIO_CONSUMERS_PER_TRIGGER This value controls the maximum number of consumers that a given trigger may handle. Default is 2. +config IIO_SW_TRIGGER + tristate "Enable software triggers support" + select IIO_CONFIGFS + help + Provides IIO core support for software triggers. A software + trigger can be created via configfs or directly by a driver + using the API provided. + config IIO_TRIGGERED_EVENT tristate select IIO_TRIGGER diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile index 39d119f18f2e..f670b82298aa 100644 --- a/drivers/iio/Makefile +++ b/drivers/iio/Makefile @@ -8,6 +8,7 @@ industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o obj-$(CONFIG_IIO_CONFIGFS) += industrialio-configfs.o +obj-$(CONFIG_IIO_SW_TRIGGER) += industrialio-sw-trigger.o obj-$(CONFIG_IIO_TRIGGERED_EVENT) += industrialio-triggered-event.o obj-y += accel/ diff --git a/drivers/iio/industrialio-sw-trigger.c b/drivers/iio/industrialio-sw-trigger.c new file mode 100644 index 000000000000..4825cfd9c4ea --- /dev/null +++ b/drivers/iio/industrialio-sw-trigger.c @@ -0,0 +1,183 @@ +/* + * The Industrial I/O core, software trigger functions + * + * Copyright (c) 2015 Intel Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/kmod.h> +#include <linux/list.h> +#include <linux/slab.h> + +#include <linux/iio/sw_trigger.h> +#include <linux/configfs.h> + +static struct config_group *iio_triggers_group; +static struct config_item_type iio_trigger_type_group_type; + +static struct config_item_type iio_triggers_group_type = { + .ct_owner = THIS_MODULE, +}; + +static LIST_HEAD(iio_trigger_types_list); +static DEFINE_MUTEX(iio_trigger_types_lock); + +static +struct iio_sw_trigger_type *__iio_find_sw_trigger_type(const char *name, + unsigned len) +{ + struct iio_sw_trigger_type *t = NULL, *iter; + + list_for_each_entry(iter, &iio_trigger_types_list, list) + if (!strcmp(iter->name, name)) { + t = iter; + break; + } + + return t; +} + +int iio_register_sw_trigger_type(struct iio_sw_trigger_type *t) +{ + struct iio_sw_trigger_type *iter; + int ret = 0; + + mutex_lock(&iio_trigger_types_lock); + iter = __iio_find_sw_trigger_type(t->name, strlen(t->name)); + if (iter) + ret = -EBUSY; + else + list_add_tail(&t->list, &iio_trigger_types_list); + mutex_unlock(&iio_trigger_types_lock); + + if (ret) + return ret; + + t->group = configfs_register_default_group(iio_triggers_group, t->name, + &iio_trigger_type_group_type); + if (IS_ERR(t->group)) + ret = PTR_ERR(t->group); + + return ret; +} +EXPORT_SYMBOL(iio_register_sw_trigger_type); + +void iio_unregister_sw_trigger_type(struct iio_sw_trigger_type *t) +{ + struct iio_sw_trigger_type *iter; + + mutex_lock(&iio_trigger_types_lock); + iter = __iio_find_sw_trigger_type(t->name, strlen(t->name)); + if (iter) + list_del(&t->list); + mutex_unlock(&iio_trigger_types_lock); + + configfs_unregister_default_group(t->group); +} +EXPORT_SYMBOL(iio_unregister_sw_trigger_type); + +static +struct iio_sw_trigger_type *iio_get_sw_trigger_type(const char *name) +{ + struct iio_sw_trigger_type *t; + + mutex_lock(&iio_trigger_types_lock); + t = __iio_find_sw_trigger_type(name, strlen(name)); + if (t && !try_module_get(t->owner)) + t = NULL; + mutex_unlock(&iio_trigger_types_lock); + + return t; +} + +struct iio_sw_trigger *iio_sw_trigger_create(const char *type, const char *name) +{ + struct iio_sw_trigger *t; + struct iio_sw_trigger_type *tt; + + tt = iio_get_sw_trigger_type(type); + if (!tt) { + pr_err("Invalid trigger type: %s\n", type); + return ERR_PTR(-EINVAL); + } + t = tt->ops->probe(name); + if (IS_ERR(t)) + goto out_module_put; + + t->trigger_type = tt; + + return t; +out_module_put: + module_put(tt->owner); + return t; +} +EXPORT_SYMBOL(iio_sw_trigger_create); + +void iio_sw_trigger_destroy(struct iio_sw_trigger *t) +{ + struct iio_sw_trigger_type *tt = t->trigger_type; + + tt->ops->remove(t); + module_put(tt->owner); +} +EXPORT_SYMBOL(iio_sw_trigger_destroy); + +static struct config_group *trigger_make_group(struct config_group *group, + const char *name) +{ + struct iio_sw_trigger *t; + + t = iio_sw_trigger_create(group->cg_item.ci_name, name); + if (IS_ERR(t)) + return ERR_CAST(t); + + config_item_set_name(&t->group.cg_item, "%s", name); + + return &t->group; +} + +static void trigger_drop_group(struct config_group *group, + struct config_item *item) +{ + struct iio_sw_trigger *t = to_iio_sw_trigger(item); + + iio_sw_trigger_destroy(t); + config_item_put(item); +} + +static struct configfs_group_operations trigger_ops = { + .make_group = &trigger_make_group, + .drop_item = &trigger_drop_group, +}; + +static struct config_item_type iio_trigger_type_group_type = { + .ct_group_ops = &trigger_ops, + .ct_owner = THIS_MODULE, +}; + +static int __init iio_sw_trigger_init(void) +{ + iio_triggers_group = + configfs_register_default_group(&iio_configfs_subsys.su_group, + "triggers", + &iio_triggers_group_type); + if (IS_ERR(iio_triggers_group)) + return PTR_ERR(iio_triggers_group); + return 0; +} +module_init(iio_sw_trigger_init); + +static void __exit iio_sw_trigger_exit(void) +{ + configfs_unregister_default_group(iio_triggers_group); +} +module_exit(iio_sw_trigger_exit); + +MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>"); +MODULE_DESCRIPTION("Industrial I/O software triggers support"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/iio/sw_trigger.h b/include/linux/iio/sw_trigger.h new file mode 100644 index 000000000000..c2f33b2b35a5 --- /dev/null +++ b/include/linux/iio/sw_trigger.h @@ -0,0 +1,71 @@ +/* + * Industrial I/O software trigger interface + * + * Copyright (c) 2015 Intel Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + */ + +#ifndef __IIO_SW_TRIGGER +#define __IIO_SW_TRIGGER + +#include <linux/module.h> +#include <linux/device.h> +#include <linux/iio/iio.h> +#include <linux/configfs.h> + +#define module_iio_sw_trigger_driver(__iio_sw_trigger_type) \ + module_driver(__iio_sw_trigger_type, iio_register_sw_trigger_type, \ + iio_unregister_sw_trigger_type) + +extern struct configfs_subsystem iio_configfs_subsys; +struct iio_sw_trigger_ops; + +struct iio_sw_trigger_type { + const char *name; + struct module *owner; + const struct iio_sw_trigger_ops *ops; + struct list_head list; + struct config_group *group; +}; + +struct iio_sw_trigger { + struct iio_trigger *trigger; + struct iio_sw_trigger_type *trigger_type; + struct config_group group; +}; + +struct iio_sw_trigger_ops { + struct iio_sw_trigger* (*probe)(const char *); + int (*remove)(struct iio_sw_trigger *); +}; + +static inline +struct iio_sw_trigger *to_iio_sw_trigger(struct config_item *item) +{ + return container_of(to_config_group(item), struct iio_sw_trigger, + group); +} + +int iio_register_sw_trigger_type(struct iio_sw_trigger_type *tt); +void iio_unregister_sw_trigger_type(struct iio_sw_trigger_type *tt); + +struct iio_sw_trigger *iio_sw_trigger_create(const char *, const char *); +void iio_sw_trigger_destroy(struct iio_sw_trigger *); + +int iio_sw_trigger_type_configfs_register(struct iio_sw_trigger_type *tt); +void iio_sw_trigger_type_configfs_unregister(struct iio_sw_trigger_type *tt); + +static inline +void iio_swt_group_init_type_name(struct iio_sw_trigger *t, + const char *name, + struct config_item_type *type) +{ +#ifdef CONFIG_CONFIGFS_FS + config_group_init_type_name(&t->group, name, type); +#endif +} + +#endif /* __IIO_SW_TRIGGER */ |