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-rw-r--r--drivers/iio/Kconfig8
-rw-r--r--drivers/iio/Makefile1
-rw-r--r--drivers/iio/industrialio-sw-trigger.c183
-rw-r--r--include/linux/iio/sw_trigger.h71
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 */