[PATCH 01/14] IIO: core support for device registration and management

From: Jonathan Cameron
Date: Thu Jul 02 2009 - 09:50:59 EST


Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxx>

---
Changes since V2.

* New structure, much closer to that on input subsystem.
An IIO device now has an associated struct device
which has the underlying hardware device (i2c, spi
etc) as its parent. This in turn has struct devices
as children for event interfaces.

* Chrdevs now handled via cdev structures with
dynamically allocated major number.

* Ring buffer and trigger functionality made more modular
(and hence hardly show up in the core at all). This
results in device drivers having to call a couple more
functions but results in a much cleaner core.
Also trigger consumer head separated from main trigger
header.

* Scan mode selection etc changed to being via access
functions to allow for simple change of implementation as
apprpriate as device requirements become apparent.

* Numerous clean ups and comment fixes.
---
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/iio/Kconfig | 11 +
drivers/iio/Makefile | 6 +
drivers/iio/industrialio-core.c | 847 ++++++++++++++++++++++++++++++++++
include/linux/iio/chrdev.h | 118 +++++
include/linux/iio/iio.h | 411 ++++++++++++++++
include/linux/iio/sysfs.h | 293 ++++++++++++
include/linux/iio/trigger_consumer.h | 26 +
9 files changed, 1715 insertions(+), 0 deletions(-)
create mode 100644 drivers/iio/Kconfig
create mode 100644 drivers/iio/Makefile
create mode 100644 drivers/iio/industrialio-core.c
create mode 100644 include/linux/iio/chrdev.h
create mode 100644 include/linux/iio/iio.h
create mode 100644 include/linux/iio/sysfs.h
create mode 100644 include/linux/iio/trigger_consumer.h

diff --git a/drivers/Kconfig b/drivers/Kconfig
index 48bbdbe..cbd7978 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -110,6 +110,8 @@ source "drivers/vlynq/Kconfig"

source "drivers/xen/Kconfig"

+source "drivers/iio/Kconfig"
+
source "drivers/staging/Kconfig"

source "drivers/platform/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index bc4205d..89d0722 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -107,6 +107,7 @@ obj-$(CONFIG_OF) += of/
obj-$(CONFIG_SSB) += ssb/
obj-$(CONFIG_VIRTIO) += virtio/
obj-$(CONFIG_VLYNQ) += vlynq/
+obj-$(CONFIG_IIO) += iio/
obj-$(CONFIG_STAGING) += staging/
obj-y += platform/
obj-y += ieee802154/
diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
new file mode 100644
index 0000000..09e4101
--- /dev/null
+++ b/drivers/iio/Kconfig
@@ -0,0 +1,11 @@
+#
+# Industrial I/O subsytem configuration
+#
+
+menuconfig IIO
+ tristate "Industrial I/O support"
+ ---help---
+ The industrial I/O subsystem provides a unified framework for
+ drivers for many different types of embedded sensors using a
+ number of different physical interfaces (i2c, spi etc). See
+ Documentation/industrialio for more information.
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
new file mode 100644
index 0000000..92b462a
--- /dev/null
+++ b/drivers/iio/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for the industrial I/O core.
+#
+
+obj-$(CONFIG_IIO) += industrialio.o
+industrialio-y := industrialio-core.o
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
new file mode 100644
index 0000000..e80800d
--- /dev/null
+++ b/drivers/iio/industrialio-core.c
@@ -0,0 +1,847 @@
+/* The industrial I/O core
+ *
+ * Copyright (c) 2008 Jonathan Cameron
+ *
+ * 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.
+ *
+ * Based on elements of hwmon and input subsystems.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/idr.h>
+#include <linux/kdev_t.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/interrupt.h>
+#include <linux/poll.h>
+#include <linux/cdev.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger_consumer.h>
+
+#define IIO_ID_PREFIX "device"
+#define IIO_ID_FORMAT IIO_ID_PREFIX "%d"
+
+/* IDR to assign each registered device a unique id*/
+static DEFINE_IDR(iio_idr);
+
+/* IDR for general event identifiers */
+static DEFINE_IDR(iio_event_idr);
+/* IDR to allocate character device minor numbers */
+static DEFINE_IDR(iio_chrdev_idr);
+/* Lock used to protect both of the above */
+static DEFINE_SPINLOCK(iio_idr_lock);
+
+dev_t iio_devt;
+EXPORT_SYMBOL(iio_devt);
+
+#define IIO_DEV_MAX 256
+static char *iio_nodename(struct device *dev)
+{
+ return kasprintf(GFP_KERNEL, "iio/%s", dev_name(dev));
+}
+
+struct class iio_class = {
+ .name = "iio",
+ .nodename = iio_nodename,
+};
+EXPORT_SYMBOL(iio_class);
+
+void __iio_change_event(struct iio_detected_event_list *ev,
+ int ev_code,
+ s64 timestamp)
+{
+ ev->ev.id = ev_code;
+ ev->ev.timestamp = timestamp;
+}
+EXPORT_SYMBOL(__iio_change_event);
+
+/* Used both in the interrupt line put events and the ring buffer ones */
+
+/* Note that in it's current form someone has to be listening before events
+ * are queued. Hence a client MUST open the chrdev before the ring buffer is
+ * switched on.
+ */
+ int __iio_push_event(struct iio_event_interface *ev_int,
+ int ev_code,
+ s64 timestamp,
+ struct iio_shared_ev_pointer *
+ shared_pointer_p)
+{
+ struct iio_detected_event_list *ev;
+ int ret = 0;
+
+ /* Does anyone care? */
+ mutex_lock(&ev_int->event_list_lock);
+ if (test_bit(IIO_BUSY_BIT_POS, &ev_int->handler.flags)) {
+ if (ev_int->current_events == ev_int->max_events)
+ return 0;
+ ev = kmalloc(sizeof(*ev), GFP_KERNEL);
+ if (ev == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ ev->ev.id = ev_code;
+ ev->ev.timestamp = timestamp;
+ ev->shared_pointer = shared_pointer_p;
+ if (ev->shared_pointer)
+ shared_pointer_p->ev_p = ev;
+
+ list_add_tail(&ev->list, &ev_int->det_events.list);
+ ev_int->current_events++;
+ mutex_unlock(&ev_int->event_list_lock);
+ wake_up_interruptible(&ev_int->wait);
+ } else
+ mutex_unlock(&ev_int->event_list_lock);
+
+error_ret:
+ return ret;
+}
+EXPORT_SYMBOL(__iio_push_event);
+
+int iio_push_event(struct iio_dev *dev_info,
+ int ev_line,
+ int ev_code,
+ s64 timestamp)
+{
+ return __iio_push_event(&dev_info->event_interfaces[ev_line],
+ ev_code, timestamp, NULL);
+}
+EXPORT_SYMBOL(iio_push_event);
+
+/* Generic interrupt line interrupt handler */
+irqreturn_t iio_interrupt_handler(int irq, void *_int_info)
+{
+ struct iio_interrupt *int_info = _int_info;
+ struct iio_dev *dev_info = int_info->dev_info;
+ struct iio_event_handler_list *p;
+ s64 time_ns;
+ unsigned long flags;
+
+ spin_lock_irqsave(&int_info->ev_list_lock, flags);
+ if (list_empty(&int_info->ev_list)) {
+ spin_unlock_irqrestore(&int_info->ev_list_lock, flags);
+ return IRQ_NONE;
+ }
+
+ time_ns = iio_get_time_ns();
+ /* detect single element list*/
+ if (list_is_singular(&int_info->ev_list)) {
+ disable_irq_nosync(irq);
+ p = list_first_entry(&int_info->ev_list,
+ struct iio_event_handler_list,
+ list);
+ /* single event handler - maybe shared */
+ p->handler(dev_info, 1, time_ns, !(p->refcount > 1));
+ } else
+ list_for_each_entry(p, &int_info->ev_list, list) {
+ disable_irq_nosync(irq);
+ p->handler(dev_info, 1, time_ns, 0);
+ }
+ spin_unlock_irqrestore(&int_info->ev_list_lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static struct iio_interrupt *iio_allocate_interrupt(void)
+{
+ struct iio_interrupt *i = kmalloc(sizeof *i, GFP_KERNEL);
+ if (i) {
+ spin_lock_init(&i->ev_list_lock);
+ INIT_LIST_HEAD(&i->ev_list);
+ }
+ return i;
+}
+
+/* Confirming the validity of supplied irq is left to drivers.*/
+int iio_register_interrupt_line(unsigned int irq,
+ struct iio_dev *dev_info,
+ int line_number,
+ unsigned long type,
+ const char *name)
+{
+ int ret;
+
+ dev_info->interrupts[line_number] = iio_allocate_interrupt();
+ if (dev_info->interrupts[line_number] == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ dev_info->interrupts[line_number]->line_number = line_number;
+ dev_info->interrupts[line_number]->irq = irq;
+ dev_info->interrupts[line_number]->dev_info = dev_info;
+
+ /* Possibly only request on demand?
+ * Can see this may complicate the handling of interrupts.
+ * However, with this approach we might end up handling lots of
+ * events no-one cares about.*/
+ ret = request_irq(irq,
+ &iio_interrupt_handler,
+ type,
+ name,
+ dev_info->interrupts[line_number]);
+
+error_ret:
+ return ret;
+}
+EXPORT_SYMBOL(iio_register_interrupt_line);
+
+/* This turns up an awful lot */
+ssize_t iio_read_const_attr(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
+}
+EXPORT_SYMBOL(iio_read_const_attr);
+
+/* Before this runs the interrupt generator must have been disabled */
+void iio_unregister_interrupt_line(struct iio_dev *dev_info, int line_number)
+{
+ /* make sure the interrupt handlers are all done */
+ flush_scheduled_work();
+ free_irq(dev_info->interrupts[line_number]->irq,
+ dev_info->interrupts[line_number]);
+ kfree(dev_info->interrupts[line_number]);
+}
+EXPORT_SYMBOL(iio_unregister_interrupt_line);
+
+/* Reference counted add and remove */
+void iio_add_event_to_list(struct iio_event_handler_list *el,
+ struct list_head *head)
+{
+ unsigned long flags;
+ struct iio_interrupt *inter = to_iio_interrupt(head);
+
+ /* take mutex to protect this element */
+ mutex_lock(&el->exist_lock);
+ if (el->refcount == 0) {
+ /* Take the event list spin lock */
+ spin_lock_irqsave(&inter->ev_list_lock, flags);
+ list_add(&el->list, head);
+ spin_unlock_irqrestore(&inter->ev_list_lock, flags);
+ }
+ el->refcount++;
+ mutex_unlock(&el->exist_lock);
+}
+EXPORT_SYMBOL(iio_add_event_to_list);
+
+void iio_remove_event_from_list(struct iio_event_handler_list *el,
+ struct list_head *head)
+{
+ unsigned long flags;
+ struct iio_interrupt *inter = to_iio_interrupt(head);
+
+ mutex_lock(&el->exist_lock);
+ el->refcount--;
+ if (el->refcount == 0) {
+ /* Take the event list spin lock */
+ spin_lock_irqsave(&inter->ev_list_lock, flags);
+ list_del_init(&el->list);
+ spin_unlock_irqrestore(&inter->ev_list_lock, flags);
+ }
+ mutex_unlock(&el->exist_lock);
+}
+EXPORT_SYMBOL(iio_remove_event_from_list);
+
+ssize_t iio_event_chrdev_read(struct file *filep,
+ char *buf,
+ size_t count,
+ loff_t *f_ps)
+{
+ struct iio_event_interface *ev_int = filep->private_data;
+ struct iio_detected_event_list *el;
+ int ret;
+ size_t len;
+
+ mutex_lock(&ev_int->event_list_lock);
+ if (list_empty(&ev_int->det_events.list)) {
+ if (filep->f_flags & O_NONBLOCK) {
+ ret = -EAGAIN;
+ goto error_mutex_unlock;
+ }
+ mutex_unlock(&ev_int->event_list_lock);
+ /* Blocking on device; waiting for something to be there */
+ ret = wait_event_interruptible(ev_int->wait,
+ !list_empty(&ev_int
+ ->det_events.list));
+ if (ret)
+ goto error_ret;
+ /* Single access device so noone else can get the data */
+ mutex_lock(&ev_int->event_list_lock);
+ }
+
+ el = list_first_entry(&ev_int->det_events.list,
+ struct iio_detected_event_list,
+ list);
+ len = sizeof el->ev;
+ if (copy_to_user(buf, &(el->ev), len)) {
+ ret = -EFAULT;
+ goto error_mutex_unlock;
+ }
+ list_del(&el->list);
+ ev_int->current_events--;
+ mutex_unlock(&ev_int->event_list_lock);
+ /*
+ * Possible concurency issue if an update of this event is on its way
+ * through. May lead to new even being removed whilst the reported event
+ * was the unescalated event. In typical use case this is not a problem
+ * as userspace will say read half the buffer due to a 50% full event
+ * which would make the correct 100% full incorrect anyway.
+ */
+ spin_lock(&el->shared_pointer->lock);
+ if (el->shared_pointer)
+ (el->shared_pointer->ev_p) = NULL;
+ spin_unlock(&el->shared_pointer->lock);
+
+ kfree(el);
+
+ return len;
+
+error_mutex_unlock:
+ mutex_unlock(&ev_int->event_list_lock);
+error_ret:
+
+ return ret;
+}
+
+int iio_event_chrdev_release(struct inode *inode, struct file *filep)
+{
+ struct iio_handler *hand = iio_cdev_to_handler(inode->i_cdev);
+ struct iio_event_interface *ev_int = hand->private;
+ struct iio_detected_event_list *el;
+
+ mutex_lock(&ev_int->event_list_lock);
+ clear_bit(IIO_BUSY_BIT_POS, &ev_int->handler.flags);
+ /*
+ * In order to maintain a clean state for reopening,
+ * clear out any awaiting events. The mask will prevent
+ * any new __iio_push_event calls running.
+ */
+ list_for_each_entry(el, &ev_int->det_events.list, list) {
+ list_del(&el->list);
+ kfree(el);
+ }
+ mutex_unlock(&ev_int->event_list_lock);
+
+ return 0;
+}
+
+int iio_event_chrdev_open(struct inode *inode, struct file *filep)
+{
+ struct iio_handler *hand = iio_cdev_to_handler(inode->i_cdev);
+
+ if (test_and_set_bit(IIO_BUSY_BIT_POS, &hand->flags)) {
+ fops_put(filep->f_op);
+ return -EBUSY;
+ }
+ filep->private_data = hand->private;
+
+ return 0;
+}
+
+static const struct file_operations iio_event_chrdev_fileops = {
+ .read = iio_event_chrdev_read,
+ .release = iio_event_chrdev_release,
+ .open = iio_event_chrdev_open,
+ .owner = THIS_MODULE,
+};
+
+static void iio_event_dev_release(struct device *dev)
+{
+ struct iio_event_interface *ev_int
+ = container_of(dev, struct iio_event_interface, dev);
+ cdev_del(&ev_int->handler.chrdev);
+ iio_device_free_chrdev_minor(MINOR(dev->devt));
+};
+
+static struct device_type iio_event_type = {
+ .release = iio_event_dev_release,
+};
+
+int iio_device_get_chrdev_minor(void)
+{
+ int ret, val;
+
+idr_again:
+ if (unlikely(idr_pre_get(&iio_chrdev_idr, GFP_KERNEL) == 0))
+ return -ENOMEM;
+ spin_lock(&iio_idr_lock);
+ ret = idr_get_new(&iio_chrdev_idr, NULL, &val);
+ spin_unlock(&iio_idr_lock);
+ if (unlikely(ret == -EAGAIN))
+ goto idr_again;
+ else if (unlikely(ret))
+ return ret;
+ if (val > IIO_DEV_MAX)
+ return -ENOMEM;
+ return val;
+}
+
+void iio_device_free_chrdev_minor(int val)
+{
+ spin_lock(&iio_idr_lock);
+ idr_remove(&iio_chrdev_idr, val);
+ spin_unlock(&iio_idr_lock);
+}
+
+int iio_setup_ev_int(struct iio_event_interface *ev_int,
+ const char *name,
+ struct module *owner,
+ struct device *dev)
+{
+ int ret, minor;
+
+ ev_int->dev.class = &iio_class;
+ ev_int->dev.parent = dev;
+ ev_int->dev.type = &iio_event_type;
+ device_initialize(&ev_int->dev);
+
+ minor = iio_device_get_chrdev_minor();
+ if (minor < 0) {
+ ret = minor;
+ goto error_device_put;
+ }
+ ev_int->dev.devt = MKDEV(MAJOR(iio_devt), minor);
+ dev_set_name(&ev_int->dev, "%s", name);
+
+ ret = device_add(&ev_int->dev);
+ if (ret)
+ goto error_free_minor;
+
+ cdev_init(&ev_int->handler.chrdev, &iio_event_chrdev_fileops);
+ ev_int->handler.chrdev.owner = owner;
+
+ mutex_init(&ev_int->event_list_lock);
+ /* discussion point - make this variable? */
+ ev_int->max_events = 10;
+ ev_int->current_events = 0;
+ INIT_LIST_HEAD(&ev_int->det_events.list);
+ init_waitqueue_head(&ev_int->wait);
+ ev_int->handler.private = ev_int;
+ ev_int->handler.flags = 0;
+
+ ret = cdev_add(&ev_int->handler.chrdev, ev_int->dev.devt, 1);
+ if (ret)
+ goto error_unreg_device;
+
+ return 0;
+
+error_unreg_device:
+ device_unregister(&ev_int->dev);
+error_free_minor:
+ iio_device_free_chrdev_minor(minor);
+error_device_put:
+ put_device(&ev_int->dev);
+
+ return ret;
+}
+
+void iio_free_ev_int(struct iio_event_interface *ev_int)
+{
+ device_unregister(&ev_int->dev);
+ put_device(&ev_int->dev);
+}
+
+static int __init iio_dev_init(void)
+{
+ int err;
+
+ err = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
+ if (err < 0)
+ printk(KERN_ERR "%s: failed to allocate char dev region\n",
+ __FILE__);
+
+ return err;
+}
+
+static void __exit iio_dev_exit(void)
+{
+ if (iio_devt)
+ unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
+}
+
+static int __init iio_init(void)
+{
+ int ret;
+
+ /* Create sysfs class */
+ ret = class_register(&iio_class);
+ if (ret < 0) {
+ printk(KERN_ERR
+ "%s could not create sysfs class\n",
+ __FILE__);
+ goto error_nothing;
+ }
+
+ ret = iio_dev_init();
+ if (ret < 0)
+ goto error_unregister_class;
+
+ return 0;
+
+error_unregister_class:
+ class_unregister(&iio_class);
+error_nothing:
+ return ret;
+}
+
+static void __exit iio_exit(void)
+{
+ iio_dev_exit();
+ class_unregister(&iio_class);
+}
+
+static int iio_device_register_sysfs(struct iio_dev *dev_info)
+{
+ int ret = 0;
+
+ ret = sysfs_create_group(&dev_info->dev.kobj, dev_info->attrs);
+ if (ret) {
+ dev_err(dev_info->dev.parent,
+ "Failed to register sysfs hooks\n");
+ goto error_ret;
+ }
+
+ if (dev_info->scan_el_attrs) {
+ ret = sysfs_create_group(&dev_info->dev.kobj,
+ dev_info->scan_el_attrs);
+ if (ret)
+ dev_err(&dev_info->dev,
+ "Failed to add sysfs scan els\n");
+ }
+
+error_ret:
+ return ret;
+}
+
+static void iio_device_unregister_sysfs(struct iio_dev *dev_info)
+{
+ if (dev_info->scan_el_attrs)
+ sysfs_remove_group(&dev_info->dev.kobj,
+ dev_info->scan_el_attrs);
+
+ sysfs_remove_group(&dev_info->dev.kobj, dev_info->attrs);
+}
+
+int iio_get_new_idr_val(struct idr *this_idr)
+{
+ int ret;
+ int val;
+
+idr_again:
+ if (unlikely(idr_pre_get(this_idr, GFP_KERNEL) == 0))
+ return -ENOMEM;
+
+ spin_lock(&iio_idr_lock);
+ ret = idr_get_new(this_idr, NULL, &val);
+ spin_unlock(&iio_idr_lock);
+ if (unlikely(ret == -EAGAIN))
+ goto idr_again;
+ else if (unlikely(ret))
+ return ret;
+
+ return val;
+}
+EXPORT_SYMBOL(iio_get_new_idr_val);
+
+void iio_free_idr_val(struct idr *this_idr, int id)
+{
+ spin_lock(&iio_idr_lock);
+ idr_remove(this_idr, id);
+ spin_unlock(&iio_idr_lock);
+}
+EXPORT_SYMBOL(iio_free_idr_val);
+
+static int iio_device_register_id(struct iio_dev *dev_info,
+ struct idr *this_idr)
+{
+
+ dev_info->id = iio_get_new_idr_val(&iio_idr);
+ if (dev_info->id < 0)
+ return dev_info->id;
+ return 0;
+}
+
+static void iio_device_unregister_id(struct iio_dev *dev_info)
+{
+ iio_free_idr_val(&iio_idr, dev_info->id);
+}
+
+static inline int __iio_add_event_config_attrs(struct iio_dev *dev_info, int i)
+{
+ int ret;
+ /*p for adding, q for removing */
+ struct attribute **attrp, **attrq;
+
+ if (dev_info->event_conf_attrs && dev_info->event_conf_attrs[i].attrs) {
+ attrp = dev_info->event_conf_attrs[i].attrs;
+ while (*attrp) {
+ ret = sysfs_add_file_to_group(&dev_info->dev.kobj,
+ *attrp,
+ dev_info
+ ->event_attrs[i].name);
+ if (ret)
+ goto error_ret;
+ attrp++;
+ }
+ }
+ return 0;
+
+error_ret:
+ attrq = dev_info->event_conf_attrs[i].attrs;
+ while (attrq != attrp) {
+ sysfs_remove_file_from_group(&dev_info->dev.kobj,
+ *attrq,
+ dev_info->event_attrs[i].name);
+ attrq++;
+ }
+
+ return ret;
+}
+
+static inline int __iio_remove_event_config_attrs(struct iio_dev *dev_info,
+ int i)
+{
+ struct attribute **attrq;
+
+ if (dev_info->event_conf_attrs
+ && dev_info->event_conf_attrs[i].attrs) {
+ attrq = dev_info->event_conf_attrs[i].attrs;
+ while (*attrq) {
+ sysfs_remove_file_from_group(&dev_info->dev.kobj,
+ *attrq,
+ dev_info
+ ->event_attrs[i].name);
+ attrq++;
+ }
+ }
+
+ return 0;
+}
+
+static int iio_device_register_eventset(struct iio_dev *dev_info)
+{
+ int ret = 0, i, j;
+
+ if (dev_info->num_interrupt_lines == 0)
+ return 0;
+
+ dev_info->event_interfaces =
+ kzalloc(sizeof(struct iio_event_interface)
+ *dev_info->num_interrupt_lines,
+ GFP_KERNEL);
+ if (dev_info->event_interfaces == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+
+ dev_info->interrupts = kzalloc(sizeof(struct iio_interrupt *)
+ *dev_info->num_interrupt_lines,
+ GFP_KERNEL);
+ if (dev_info->interrupts == NULL) {
+ ret = -ENOMEM;
+ goto error_free_event_interfaces;
+ }
+
+ for (i = 0; i < dev_info->num_interrupt_lines; i++) {
+ dev_info->event_interfaces[i].owner = dev_info->driver_module;
+ ret = iio_get_new_idr_val(&iio_event_idr);
+ if (ret)
+ goto error_free_setup_ev_ints;
+ else
+ dev_info->event_interfaces[i].id = ret;
+
+ snprintf(dev_info->event_interfaces[i]._name, 20,
+ "event_line%d",
+ dev_info->event_interfaces[i].id);
+
+ ret = iio_setup_ev_int(&dev_info->event_interfaces[i],
+ (const char *)(dev_info
+ ->event_interfaces[i]
+ ._name),
+ dev_info->driver_module,
+ &dev_info->dev);
+ if (ret) {
+ dev_err(&dev_info->dev,
+ "Could not get chrdev interface\n");
+ iio_free_idr_val(&iio_event_idr,
+ dev_info->event_interfaces[i].id);
+ goto error_free_setup_ev_ints;
+ }
+ }
+
+ for (i = 0; i < dev_info->num_interrupt_lines; i++) {
+ snprintf(dev_info->event_interfaces[i]._attrname, 20,
+ "event_line%d_sources", i);
+ dev_info->event_attrs[i].name
+ = (const char *)
+ (dev_info->event_interfaces[i]._attrname);
+ ret = sysfs_create_group(&dev_info->dev.kobj,
+ &dev_info->event_attrs[i]);
+ if (ret) {
+ dev_err(&dev_info->dev,
+ "Failed to register sysfs for event attrs");
+ goto error_remove_sysfs_interfaces;
+ }
+ }
+
+ for (i = 0; i < dev_info->num_interrupt_lines; i++) {
+ ret = __iio_add_event_config_attrs(dev_info, i);
+ if (ret)
+ goto error_unregister_config_attrs;
+ }
+
+ return 0;
+
+error_unregister_config_attrs:
+ for (j = 0; j < i; j++)
+ __iio_remove_event_config_attrs(dev_info, i);
+ i = dev_info->num_interrupt_lines - 1;
+error_remove_sysfs_interfaces:
+ for (j = 0; j < i; j++)
+ sysfs_remove_group(&dev_info->dev.kobj,
+ &dev_info->event_attrs[j]);
+ i = dev_info->num_interrupt_lines - 1;
+error_free_setup_ev_ints:
+ for (j = 0; j < i; j++) {
+ iio_free_idr_val(&iio_event_idr,
+ dev_info->event_interfaces[i].id);
+ iio_free_ev_int(&dev_info->event_interfaces[j]);
+ }
+ kfree(dev_info->interrupts);
+error_free_event_interfaces:
+ kfree(dev_info->event_interfaces);
+error_ret:
+
+ return ret;
+}
+
+static void iio_device_unregister_eventset(struct iio_dev *dev_info)
+{
+ int i;
+
+ if (dev_info->num_interrupt_lines == 0)
+ return;
+ for (i = 0; i < dev_info->num_interrupt_lines; i++)
+ sysfs_remove_group(&dev_info->dev.kobj,
+ &dev_info->event_attrs[i]);
+
+ for (i = 0; i < dev_info->num_interrupt_lines; i++) {
+ iio_free_idr_val(&iio_event_idr,
+ dev_info->event_interfaces[i].id);
+ iio_free_ev_int(&dev_info->event_interfaces[i]);
+ }
+ kfree(dev_info->interrupts);
+ kfree(dev_info->event_interfaces);
+}
+
+static void iio_dev_release(struct device *device)
+{
+ struct iio_dev *dev = to_iio_dev(device);
+
+ iio_put();
+ kfree(dev);
+}
+
+static struct device_type iio_dev_type = {
+ .name = "iio_device",
+ .release = iio_dev_release,
+};
+
+struct iio_dev *iio_allocate_device(void)
+{
+ struct iio_dev *dev = kzalloc(sizeof *dev, GFP_KERNEL);
+
+ if (dev) {
+ dev->dev.type = &iio_dev_type;
+ dev->dev.class = &iio_class;
+ device_initialize(&dev->dev);
+ dev_set_drvdata(&dev->dev, (void *)dev);
+ mutex_init(&dev->mlock);
+ iio_get();
+ }
+
+ return dev;
+}
+EXPORT_SYMBOL(iio_allocate_device);
+
+void iio_free_device(struct iio_dev *dev)
+{
+ if (dev)
+ iio_put_device(dev);
+}
+EXPORT_SYMBOL(iio_free_device);
+
+int iio_device_register(struct iio_dev *dev_info)
+{
+ int ret;
+
+ ret = iio_device_register_id(dev_info, &iio_idr);
+ if (ret) {
+ dev_err(&dev_info->dev, "Failed to get id\n");
+ goto error_ret;
+ }
+ dev_set_name(&dev_info->dev, "device%d", dev_info->id);
+
+ ret = device_add(&dev_info->dev);
+ if (ret)
+ goto error_free_idr;
+ ret = iio_device_register_sysfs(dev_info);
+ if (ret) {
+ dev_err(dev_info->dev.parent,
+ "Failed to register sysfs interfaces\n");
+ goto error_del_device;
+ }
+ ret = iio_device_register_eventset(dev_info);
+ if (ret) {
+ dev_err(dev_info->dev.parent,
+ "Failed to register event set \n");
+ goto error_free_sysfs;
+ }
+ if (dev_info->modes & INDIO_RING_TRIGGERED)
+ iio_device_register_trigger_consumer(dev_info);
+
+ return 0;
+
+error_free_sysfs:
+ iio_device_unregister_sysfs(dev_info);
+error_del_device:
+ device_del(&dev_info->dev);
+error_free_idr:
+ iio_device_unregister_id(dev_info);
+error_ret:
+ return ret;
+}
+EXPORT_SYMBOL(iio_device_register);
+
+void iio_device_unregister(struct iio_dev *dev_info)
+{
+ if (dev_info->modes & INDIO_RING_TRIGGERED)
+ iio_device_unregister_trigger_consumer(dev_info);
+ iio_device_unregister_eventset(dev_info);
+ iio_device_unregister_sysfs(dev_info);
+ device_unregister(&dev_info->dev);
+ iio_device_unregister_id(dev_info);
+}
+EXPORT_SYMBOL(iio_device_unregister);
+
+void iio_put(void)
+{
+ module_put(THIS_MODULE);
+}
+
+void iio_get(void)
+{
+ __module_get(THIS_MODULE);
+}
+
+subsys_initcall(iio_init);
+module_exit(iio_exit);
+
+MODULE_AUTHOR("Jonathan Cameron <jic23@xxxxxxxxx>");
+MODULE_DESCRIPTION("Industrial I/O core");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/iio/chrdev.h b/include/linux/iio/chrdev.h
new file mode 100644
index 0000000..8bc64bf
--- /dev/null
+++ b/include/linux/iio/chrdev.h
@@ -0,0 +1,118 @@
+/* The industrial I/O core - character device related
+ *
+ * Copyright (c) 2008 Jonathan Cameron
+ *
+ * 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_CHRDEV_H_
+#define _IIO_CHRDEV_H_
+struct iio_dev;
+
+/**
+ * struct iio_handler - Structure used to specify file operations
+ * for a particular chrdev
+ * @chrdev: character device structure
+ * @id: the location in the handler table - used for deallocation.
+ * @flags: file operations related flags including busy flag.
+ * @private: handler specific data used by the fileops registered with
+ * the chrdev.
+ */
+struct iio_handler {
+ struct cdev chrdev;
+ int id;
+ unsigned long flags;
+ void *private;
+};
+
+#define iio_cdev_to_handler(cd) \
+ container_of(cd, struct iio_handler, chrdev)
+
+/**
+ * struct iio_event_data - The actual event being pushed to userspace
+ * @id: event identifier
+ * @timestamp: best estimate of time of event occurance (often from
+ * the interrupt handler)
+ */
+struct iio_event_data {
+ int id;
+ s64 timestamp;
+};
+
+/**
+ * struct iio_detected_event_list - list element for events that have occured
+ * @list: linked list header
+ * @ev: the event itself
+ * @shared_pointer: used when the event is shared - i.e. can be escallated
+ * on demand (eg ring buffer 50%->100% full)
+ */
+struct iio_detected_event_list {
+ struct list_head list;
+ struct iio_event_data ev;
+ struct iio_shared_ev_pointer *shared_pointer;
+};
+/**
+ * struct iio_shared_ev_pointer - allows shared events to identify if currently
+ * in the detected event list
+ * @ev_p: pointer to detected event list element (null if not in list)
+ * @lock: protect this element to prevent simultaneous edit and remove
+ */
+struct iio_shared_ev_pointer {
+ struct iio_detected_event_list *ev_p;
+ spinlock_t lock;
+};
+
+/**
+ * struct iio_event_interface - chrdev interface for an event line
+ * @dev: device assocated with event interface
+ * @handler: fileoperations and related control for the chrdev
+ * @wait: wait queue to allow blocking reads of events
+ * @event_list_lock: mutex to protect the list of detected events
+ * @det_events: list of detected events
+ * @max_events: maximum number of events before new ones are dropped
+ * @current_events: number of events in detected list
+ * @id: indentifier to allow the event interface to know which
+ * physical line it corresponds to
+ * @owner: ensure the driver module owns the file, not iio
+ * @private: driver specific data
+ * @_name: used internally to store the sysfs name for minor id
+ * attribute
+ */
+struct iio_event_interface {
+ struct device dev;
+ struct iio_handler handler;
+ wait_queue_head_t wait;
+ struct mutex event_list_lock;
+ struct iio_detected_event_list det_events;
+ int max_events;
+ int current_events;
+ int id;
+ struct iio_chrdev_minor_attr attr;
+ struct module *owner;
+ void *private;
+ char _name[20];
+ char _attrname[20];
+};
+
+/**
+ * struct iio_event_handler_list - element in list of handlers for events
+ * @list: list header
+ * @refcount: as the handler may be shared between multiple device
+ * side events, reference counting ensures clean removal
+ * @exist_lock: prevents race conditions related to refcount useage.
+ * @handler: event handler function - called on event if this
+ * event_handler is enabled.
+ *
+ * Each device has one list of these per interrupt line
+ **/
+struct iio_event_handler_list {
+ struct list_head list;
+ int refcount;
+ struct mutex exist_lock;
+ int (*handler)(struct iio_dev *dev_info, int index, s64 timestamp,
+ int no_test);
+};
+
+#endif
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
new file mode 100644
index 0000000..2eaf8f6
--- /dev/null
+++ b/include/linux/iio/iio.h
@@ -0,0 +1,411 @@
+/* The industrial I/O core
+ *
+ * Copyright (c) 2008 Jonathan Cameron
+ *
+ * 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 _INDUSTRIAL_IO_H_
+#define _INDUSTRIAL_IO_H_
+
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/chrdev.h>
+
+/* IIO TODO LIST */
+/* Static device specific elements (conversion factors etc)
+ * should be exported via sysfs
+ *
+ * Provide means of adjusting timer accuracy.
+ * Currently assumes nano seconds.
+ */
+
+/* Event interface flags */
+#define IIO_BUSY_BIT_POS 1
+
+struct iio_dev;
+
+/**
+ * iio_get_time_ns() - utility function to get a time stamp for events etc
+ **/
+static inline s64 iio_get_time_ns(void)
+{
+ struct timespec ts;
+ /*
+ * calls getnstimeofday.
+ * If hrtimers then up to ns accurate, if not microsecond.
+ */
+ ktime_get_real_ts(&ts);
+
+ return timespec_to_ns(&ts);
+}
+
+/**
+ * iio_add_event_to_list() - Wraps adding to event lists
+ * @el: the list element of the event to be handled.
+ * @head: the list associated with the event handler being used.
+ *
+ * Does reference counting to allow shared handlers.
+ **/
+void iio_add_event_to_list(struct iio_event_handler_list *el,
+ struct list_head *head);
+
+/**
+ * iio_remove_event_from_list() - Wraps removing from event list
+ * @el: element to be removed
+ * @head: associate list head for the interrupt handler.
+ *
+ * Does reference counting to allow shared handlers.
+ **/
+void iio_remove_event_from_list(struct iio_event_handler_list *el,
+ struct list_head *head);
+
+/* Device operating modes */
+#define INDIO_DIRECT_MODE 0x01
+#define INDIO_RING_TRIGGERED 0x02
+#define INDIO_RING_HARDWARE_BUFFER 0x08
+
+#define INDIO_ALL_RING_MODES (INDIO_RING_TRIGGERED | INDIO_RING_HARDWARE_BUFFER)
+
+/* Vast majority of this is set by the industrialio subsystem on a
+ * call to iio_device_register. */
+
+/**
+ * struct iio_dev - industrial I/O device
+ * @id: [INTERN] used to identify device internally
+ * @dev_data: [DRIVER] device specific data
+ * @modes: [DRIVER] operating modes supported by device
+ * @currentmode: [DRIVER] current operating mode
+ * @dev: [DRIVER] device structure, should be assigned a parent
+ * and owner
+ * @attrs: [DRIVER] general purpose device attributes
+ * @driver_module: [DRIVER] module structure used to ensure correct
+ * ownership of chrdevs etc
+ * @num_interrupt_lines:[DRIVER] number of physical interrupt lines from device
+ * @interrupts: [INTERN] interrupt line specific event lists etc
+ * @event_attrs: [DRIVER] event control attributes
+ * @event_conf_attrs: [DRIVER] event configuration attributes
+ * @event_interfaces: [INTERN] event chrdevs associated with interrupt lines
+ * @ring: [DRIVER] any ring buffer present
+ * @mlock: [INTERN] lock used to prevent simultaneous device state
+ * changes
+ * @scan_el_attrs: [DRIVER] control of scan elements if that scan mode
+ * control method is used
+ * @scan_count: [INTERN] the number of elements in the current scan mode
+ * @scan_mask: [INTERN] bitmask used in masking scan mode elements
+ * @scan_timestamp: [INTERN] does the scan mode include a timestamp
+ * @trig: [INTERN] current device trigger (ring buffer modes)
+ * @pollfunc: [DRIVER] function run on trigger being recieved
+ **/
+struct iio_dev {
+ int id;
+ void *dev_data;
+ int modes;
+ int currentmode;
+ struct device dev;
+ const struct attribute_group *attrs;
+ struct module *driver_module;
+
+ int num_interrupt_lines;
+ struct iio_interrupt **interrupts;
+ struct attribute_group *event_attrs;
+ struct attribute_group *event_conf_attrs;
+
+ struct iio_event_interface *event_interfaces;
+
+ struct iio_ring_buffer *ring;
+ struct mutex mlock;
+
+ struct attribute_group *scan_el_attrs;
+ int scan_count;
+
+ u16 scan_mask;
+ bool scan_timestamp;
+ struct iio_trigger *trig;
+ struct iio_poll_func *pollfunc;
+};
+
+/*
+ * These are mainly provided to allow for a change of implementation if a device
+ * has a large number of scan elements
+ */
+#define IIO_MAX_SCAN_LENGTH 15
+
+static inline int iio_scan_mask_query(struct iio_dev *dev_info, int bit)
+{
+ if (bit > IIO_MAX_SCAN_LENGTH)
+ return -EINVAL;
+ else
+ return !!(dev_info->scan_mask & (1 << bit));
+};
+
+static inline int iio_scan_mask_set(struct iio_dev *dev_info, int bit)
+{
+ if (bit > IIO_MAX_SCAN_LENGTH)
+ return -EINVAL;
+ dev_info->scan_mask |= (1 << bit);
+ dev_info->scan_count++;
+ return 0;
+};
+
+static inline int iio_scan_mask_clear(struct iio_dev *dev_info, int bit)
+{
+ if (bit > IIO_MAX_SCAN_LENGTH)
+ return -EINVAL;
+ dev_info->scan_mask &= ~(1 << bit);
+ dev_info->scan_count--;
+ return 0;
+};
+
+/**
+ * iio_scan_mask_count_to_right() - how many scan elements occur before here
+ * @dev_info: the iio_device whose scan mode we are querying
+ * @bit: which number scan element is this
+ **/
+static inline int iio_scan_mask_count_to_right(struct iio_dev *dev_info,
+int bit)
+{
+ int count = 0;
+ int mask = (1 << bit);
+ if (bit > IIO_MAX_SCAN_LENGTH)
+ return -EINVAL;
+ while (mask) {
+ mask >>= 1;
+ if (mask & dev_info->scan_mask)
+ count++;
+ }
+
+ return count;
+}
+
+/**
+ * iio_device_register() - register a device with the IIO subsystem
+ * @dev_info: Device structure filled by the device driver
+ **/
+int iio_device_register(struct iio_dev *dev_info);
+
+/**
+ * iio_device_unregister() - unregister a device from the IIO subsystem
+ * @dev_info: Device structure representing the device.
+ **/
+void iio_device_unregister(struct iio_dev *dev_info);
+
+/**
+ * struct iio_interrupt - wrapper used to allow easy handling of multiple
+ * physical interrupt lines
+ * @dev_info: the iio device for which the is an interrupt line
+ * @line_number: associated line number
+ * @id: idr allocated unique id number
+ * @irq: associate interrupt number
+ * @ev_list: event handler list for associated events
+ * @ev_list_lock: ensure only one access to list at a time
+ **/
+struct iio_interrupt {
+ struct iio_dev *dev_info;
+ int line_number;
+ int id;
+ int irq;
+ struct list_head ev_list;
+ spinlock_t ev_list_lock;
+};
+
+#define to_iio_interrupt(i) container_of(i, struct iio_interrupt, ev_list)
+
+/**
+ * iio_register_interrupt_line() - Tell IIO about interrupt lines
+ *
+ * @irq: Typically provided via platform data
+ * @dev_info: IIO device info structure for device
+ * @line_number: Which interrupt line of the device is this?
+ * @type: Interrupt type (e.g. edge triggered etc)
+ * @name: Identifying name.
+ **/
+int iio_register_interrupt_line(unsigned int irq,
+ struct iio_dev *dev_info,
+ int line_number,
+ unsigned long type,
+ const char *name);
+
+void iio_unregister_interrupt_line(struct iio_dev *dev_info,
+ int line_number);
+
+
+
+/**
+ * iio_push_event() - try to add event to the list for userspace reading
+ * @dev_info: IIO device structure
+ * @ev_line: Which event line (hardware interrupt)
+ * @ev_code: What event
+ * @timestamp: When the event occured
+ **/
+int iio_push_event(struct iio_dev *dev_info,
+ int ev_line,
+ int ev_code,
+ s64 timestamp);
+
+/**
+ * struct iio_work_cont - container for when singleton handler case matters
+ * @ws: [DEVICE]work_struct when not only possible event
+ * @ws_nocheck: [DEVICE]work_struct when only possible event
+ * @address: [DEVICE]associated register address
+ * @mask: [DEVICE]associated mask for identifying event source
+ * @st: [DEVICE]device specific state information
+ **/
+struct iio_work_cont {
+ struct work_struct ws;
+ struct work_struct ws_nocheck;
+ int address;
+ int mask;
+ void *st;
+};
+
+#define to_iio_work_cont_check(_ws) \
+ container_of(_ws, struct iio_work_cont, ws)
+
+#define to_iio_work_cont_no_check(_ws) \
+ container_of(_ws, struct iio_work_cont, ws_nocheck)
+
+/**
+ * iio_init_work_cont() - intiialize the elements of a work container
+ * @cont: the work container
+ * @_checkfunc: function called when there are multiple possible int sources
+ * @_nocheckfunc: function for when there is only one int source
+ * @_add: driver dependant, typically a register address
+ * @_mask: driver dependant, typically a bit mask for a register
+ * @_st: driver dependant, typically pointer to a device state structure
+ **/
+static inline void
+iio_init_work_cont(struct iio_work_cont *cont,
+ void (*_checkfunc)(struct work_struct *),
+ void (*_nocheckfunc)(struct work_struct *),
+ int _add, int _mask, void *_st)
+{
+ INIT_WORK(&(cont)->ws, _checkfunc);
+ INIT_WORK(&(cont)->ws_nocheck, _nocheckfunc);
+ cont->address = _add;
+ cont->mask = _mask;
+ cont->st = _st;
+}
+/**
+ * __iio_push_event() tries to add an event to the list associated with a chrdev
+ * @ev_int: the event interface to which we are pushing the event
+ * @ev_code: the outgoing event code
+ * @timestamp: timestamp of the event
+ * @shared_pointer_p: the shared event pointer
+ **/
+int __iio_push_event(struct iio_event_interface *ev_int,
+ int ev_code,
+ s64 timestamp,
+ struct iio_shared_ev_pointer*
+ shared_pointer_p);
+/**
+ * __iio_change_event() change an event code in case of event escallation
+ * @ev: the evnet to be changed
+ * @ev_code: new event code
+ * @timestamp: new timestamp
+ **/
+void __iio_change_event(struct iio_detected_event_list *ev,
+ int ev_code,
+ s64 timestamp);
+
+/**
+ * iio_setup_ev_int() Configure an event interface (chrdev)
+ * @name: name used for resulting sysfs directory etc.
+ * @ev_int: interface we are configuring
+ * @owner: module that is responsible for registering this ev_int
+ * @dev: device whose ev_int this is
+ **/
+int iio_setup_ev_int(struct iio_event_interface *ev_int,
+ const char *name,
+ struct module *owner,
+ struct device *dev);
+
+void iio_free_ev_int(struct iio_event_interface *ev_int);
+
+/**
+ * iio_allocate_chrdev() - Allocate a chrdev
+ * @handler: struct that contains relevant file handling for chrdev
+ * @dev_info: iio_dev for which chrdev is being created
+ **/
+int iio_allocate_chrdev(struct iio_handler *handler, struct iio_dev *dev_info);
+void iio_deallocate_chrdev(struct iio_handler *handler);
+
+/* Used to distinguish between bipolar and unipolar scan elemenents.
+ * Whilst this may seem obvious, we may well want to change the representation
+ * in the future!*/
+#define IIO_SIGNED(a) -(a)
+#define IIO_UNSIGNED(a) (a)
+
+extern dev_t iio_devt;
+extern struct class iio_class;
+
+/**
+ * iio_put_device() - reference counted deallocated of struct device
+ * @dev: the iio_device containing the device
+ **/
+static inline void iio_put_device(struct iio_dev *dev)
+{
+ if (dev)
+ put_device(&dev->dev);
+};
+
+/**
+ * to_iio_dev() - get iio_dev for which we have have the struct device
+ * @d: the struct device
+ **/
+static inline struct iio_dev *to_iio_dev(struct device *d)
+{
+ return container_of(d, struct iio_dev, dev);
+};
+
+/**
+ * iio_dev_get_devdata() - helper function gets device specific data
+ * @d: the iio_dev associated with the device
+ **/
+static inline void *iio_dev_get_devdata(struct iio_dev *d)
+{
+ return d->dev_data;
+}
+
+/**
+ * iio_allocate_device() - allocate an iio_dev from a driver
+ **/
+struct iio_dev *iio_allocate_device(void);
+
+/**
+ * iio_free_device() - free an iio_dev from a driver
+ **/
+void iio_free_device(struct iio_dev *dev);
+
+/**
+ * iio_put() - internal module reference count reduce
+ **/
+void iio_put(void);
+
+/**
+ * iio_get() - internal module reference count increase
+ **/
+void iio_get(void);
+
+/* Ring buffer related */
+int iio_device_get_chrdev_minor(void);
+void iio_device_free_chrdev_minor(int val);
+
+/**
+ * iio_ring_enabled() helper function to test if any form of ring enabled
+ **/
+static inline bool iio_ring_enabled(struct iio_dev *dev_info)
+{
+ return dev_info->currentmode
+ & (INDIO_RING_TRIGGERED
+ | INDIO_RING_HARDWARE_BUFFER);
+};
+
+struct idr;
+
+int iio_get_new_idr_val(struct idr *this_idr);
+void iio_free_idr_val(struct idr *this_idr, int id);
+#endif /* _INDUSTRIAL_IO_H_ */
diff --git a/include/linux/iio/sysfs.h b/include/linux/iio/sysfs.h
new file mode 100644
index 0000000..d003d36
--- /dev/null
+++ b/include/linux/iio/sysfs.h
@@ -0,0 +1,293 @@
+/* The industrial I/O core
+ *
+ *Copyright (c) 2008 Jonathan Cameron
+ *
+ * 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.
+ *
+ * General attributes
+ */
+
+#ifndef _INDUSTRIAL_IO_SYSFS_H_
+#define _INDUSTRIAL_IO_SYSFS_H_
+
+#include <linux/iio/iio.h>
+
+/**
+ * struct iio_event_attribute - event control attribute
+ * @dev_attr: underlying device attribute
+ * @mask: mask for the event when detecting
+ * @listel: list header to allow addition to list of event handlers
+*/
+struct iio_event_attr {
+ struct device_attribute dev_attr;
+ int mask;
+ struct iio_event_handler_list *listel;
+};
+
+#define to_iio_event_attr(_dev_attr) \
+ container_of(_dev_attr, struct iio_event_attr, dev_attr)
+
+/**
+ * struct iio_chrdev_minor_attr - simple attribute to allow reading of chrdev
+ * minor number
+ * @dev_attr: underlying device attribute
+ * @minor: the minor number
+ */
+struct iio_chrdev_minor_attr {
+ struct device_attribute dev_attr;
+ int minor;
+};
+
+void
+__init_iio_chrdev_minor_attr(struct iio_chrdev_minor_attr *minor_attr,
+ const char *name,
+ struct module *owner,
+ int id);
+
+
+#define to_iio_chrdev_minor_attr(_dev_attr) \
+ container_of(_dev_attr, struct iio_chrdev_minor_attr, dev_attr);
+
+/**
+ * struct iio_dev_attr - iio specific device attribute
+ * @dev_attr: underlying device attribute
+ * @address: associated register address
+ */
+struct iio_dev_attr {
+ struct device_attribute dev_attr;
+ int address;
+ int val2;
+};
+
+#define to_iio_dev_attr(_dev_attr) \
+ container_of(_dev_attr, struct iio_dev_attr, dev_attr)
+
+ssize_t iio_read_const_attr(struct device *dev,
+ struct device_attribute *attr,
+ char *len);
+
+/**
+ * struct iio_const_attr - constant device specific attribute
+ * often used for things like available modes
+ */
+struct iio_const_attr {
+ const char *string;
+ struct device_attribute dev_attr;
+};
+
+#define to_iio_const_attr(_dev_attr) \
+ container_of(_dev_attr, struct iio_const_attr, dev_attr)
+
+/* Some attributes will be hard coded (device dependant) and not require an
+ address, in these cases pass a negative */
+#define IIO_ATTR(_name, _mode, _show, _store, _addr) \
+ { .dev_attr = __ATTR(_name, _mode, _show, _store), \
+ .address = _addr }
+
+#define IIO_ATTR_2(_name, _mode, _show, _store, _addr, _val2) \
+ { .dev_attr = __ATTR(_name, _mode, _show, _store), \
+ .address = _addr, \
+ .val2 = _val2 }
+
+#define IIO_DEVICE_ATTR(_name, _mode, _show, _store, _addr) \
+ struct iio_dev_attr iio_dev_attr_##_name \
+ = IIO_ATTR(_name, _mode, _show, _store, _addr)
+
+
+#define IIO_DEVICE_ATTR_2(_name, _mode, _show, _store, _addr, _val2) \
+ struct iio_dev_attr iio_dev_attr_##_name \
+ = IIO_ATTR_2(_name, _mode, _show, _store, _addr, _val2)
+
+#define IIO_CONST_ATTR(_name, _string) \
+ struct iio_const_attr iio_const_attr_##_name \
+ = { .string = _string, \
+ .dev_attr = __ATTR(_name, S_IRUGO, iio_read_const_attr, NULL)}
+
+/* Generic attributes of onetype or another */
+
+/**
+ * IIO_DEV_ATTR_REG: revision number for the device
+ *
+ * Very much device dependent.
+ **/
+#define IIO_DEV_ATTR_REV(_show) \
+ IIO_DEVICE_ATTR(revision, S_IRUGO, _show, NULL, 0)
+/**
+ * IIO_DEV_ATTR_NAME: chip type dependant identifier
+ **/
+#define IIO_DEV_ATTR_NAME(_show) \
+ IIO_DEVICE_ATTR(name, S_IRUGO, _show, NULL, 0)
+
+/**
+ * IIO_DEV_ATTR_SAMP_FREQ: sets any internal clock frequency
+ **/
+#define IIO_DEV_ATTR_SAMP_FREQ(_mode, _show, _store) \
+ IIO_DEVICE_ATTR(sampling_frequency, _mode, _show, _store, 0)
+
+/**
+ * IIO_DEV_ATTR_AVAIL_SAMP_FREQ: list available sampling frequencies.
+ *
+ * May be mode dependant on some devices
+ **/
+#define IIO_DEV_ATTR_AVAIL_SAMP_FREQ(_show) \
+ IIO_DEVICE_ATTR(available_sampling_frequency, S_IRUGO, _show, NULL, 0)
+
+/**
+ * IIO_DEV_ATTR_CONST_AVAIL_SAMP_FREQ: list available sampling frequencies.
+ *
+ * Constant version
+ **/
+#define IIO_CONST_ATTR_AVAIL_SAMP_FREQ(_string) \
+ IIO_CONST_ATTR(available_sampling_frequency, _string)
+/**
+ * IIO_DEV_ATTR_SCAN_MODE: select a scan mode
+ *
+ * This is used when only certain combinations of inputs may be read in one
+ * scan.
+ **/
+#define IIO_DEV_ATTR_SCAN_MODE(_mode, _show, _store) \
+ IIO_DEVICE_ATTR(scan_mode, _mode, _show, _store, 0)
+/**
+ * IIO_DEV_ATTR_AVAIL_SCAN_MODES: list available scan modes
+ **/
+#define IIO_DEV_ATTR_AVAIL_SCAN_MODES(_show) \
+ IIO_DEVICE_ATTR(available_scan_modes, S_IRUGO, _show, NULL, 0)
+
+/**
+ * IIO_DEV_ATTR_SCAN: result of scan of multiple channels
+ **/
+#define IIO_DEV_ATTR_SCAN(_show) \
+ IIO_DEVICE_ATTR(scan, S_IRUGO, _show, NULL, 0);
+
+/**
+ * IIO_DEV_ATTR_INPUT: direct read of a single input channel
+ **/
+#define IIO_DEV_ATTR_INPUT(_number, _show) \
+ IIO_DEVICE_ATTR(in##_number, S_IRUGO, _show, NULL, _number)
+
+
+/**
+ * IIO_DEV_ATTR_SW_RING_ENABLE: enable software ring buffer
+ *
+ * Success may be dependant on attachment of trigger previously
+ **/
+#define IIO_DEV_ATTR_SW_RING_ENABLE(_show, _store) \
+ IIO_DEVICE_ATTR(sw_ring_enable, S_IRUGO | S_IWUSR, _show, _store, 0)
+
+/**
+ * IIO_DEV_ATTR_HW_RING_ENABLE: enable hardware ring buffer
+ *
+ * This is a different attribute from the software one as one can invision
+ * schemes where a combination of the two may be used.
+ **/
+#define IIO_DEV_ATTR_HW_RING_ENABLE(_show, _store) \
+ IIO_DEVICE_ATTR(hw_ring_enable, S_IRUGO | S_IWUSR, _show, _store, 0)
+
+/**
+ * IIO_DEV_ATTR_BPSE: set number of bits per scan element
+ **/
+#define IIO_DEV_ATTR_BPSE(_mode, _show, _store) \
+ IIO_DEVICE_ATTR(bpse, _mode, _show, _store, 0)
+
+/**
+ * IIO_DEV_ATTR_BPSE_AVAILABLE: no of bits per scan element supported
+ **/
+#define IIO_DEV_ATTR_BPSE_AVAILABLE(_show) \
+ IIO_DEVICE_ATTR(bpse_available, S_IRUGO, _show, NULL, 0)
+
+/**
+ * IIO_DEV_ATTR_TEMP: many sensors have auxiliary temperature sensors
+ **/
+#define IIO_DEV_ATTR_TEMP(_show) \
+ IIO_DEVICE_ATTR(temp, S_IRUGO, _show, NULL, 0)
+/**
+ * IIO_EVENT_SH: generic shared event handler
+ *
+ * This is used in cases where more than one event may result from a single
+ * handler. Often the case that some alarm register must be read and multiple
+ * alarms may have been triggered.
+ **/
+#define IIO_EVENT_SH(_name, _handler) \
+ static struct iio_event_handler_list \
+ iio_event_##_name = { \
+ .handler = _handler, \
+ .refcount = 0, \
+ .exist_lock = __MUTEX_INITIALIZER(iio_event_##_name \
+ .exist_lock), \
+ .list = { \
+ .next = &iio_event_##_name.list, \
+ .prev = &iio_event_##_name.list, \
+ }, \
+ };
+/**
+ * IIO_EVENT_ATTR_SH: generic shared event attribute
+ *
+ * An attribute with an associated IIO_EVENT_SH
+ **/
+#define IIO_EVENT_ATTR_SH(_name, _ev_list, _show, _store, _mask) \
+ static struct iio_event_attr \
+ iio_event_attr_##_name \
+ = { .dev_attr = __ATTR(_name, S_IRUGO | S_IWUSR, \
+ _show, _store), \
+ .mask = _mask, \
+ .listel = &_ev_list };
+
+/**
+ * IIO_EVENT_ATTR: non shared event attribute
+ **/
+#define IIO_EVENT_ATTR(_name, _show, _store, _mask, _handler) \
+ static struct iio_event_handler_list \
+ iio_event_##_name = { \
+ .handler = _handler, \
+ }; \
+ static struct \
+ iio_event_attr \
+ iio_event_attr_##_name \
+ = { .dev_attr = __ATTR(_name, S_IRUGO | S_IWUSR, \
+ _show, _store), \
+ .mask = _mask, \
+ .listel = &iio_event_##_name }; \
+
+/**
+ * IIO_EVENT_ATTR_DATA_RDY: event driven by data ready signal
+ *
+ * Not typically implemented in devices where full triggering support
+ * has been implemented
+ **/
+#define IIO_EVENT_ATTR_DATA_RDY(_show, _store, _mask, _handler) \
+ IIO_EVENT_ATTR(data_rdy, _show, _store, _mask, _handler)
+
+#define IIO_EVENT_CODE_DATA_RDY 100
+#define IIO_EVENT_CODE_RING_BASE 200
+#define IIO_EVENT_CODE_ACCEL_BASE 300
+#define IIO_EVENT_CODE_GYRO_BASE 400
+#define IIO_EVENT_CODE_ADC_BASE 500
+#define IIO_EVENT_CODE_MISC_BASE 600
+
+#define IIO_EVENT_CODE_DEVICE_SPECIFIC 1000
+
+/**
+ * IIO_EVENT_ATTR_RING_50_FULL: ring buffer event to indicate 50% full
+ **/
+#define IIO_EVENT_ATTR_RING_50_FULL(_show, _store, _mask, _handler) \
+ IIO_EVENT_ATTR(ring_50_full, _show, _store, _mask, _handler)
+
+/**
+ * IIO_EVENT_ATTR_RING_50_FULL_SH: shared ring event to indicate 50% full
+ **/
+#define IIO_EVENT_ATTR_RING_50_FULL_SH(_evlist, _show, _store, _mask) \
+ IIO_EVENT_ATTR_SH(ring_50_full, _evlist, _show, _store, _mask)
+
+/**
+ * IIO_EVENT_ATTR_RING_75_FULL_SH: shared ring event to indicate 75% full
+ **/
+#define IIO_EVENT_ATTR_RING_75_FULL_SH(_evlist, _show, _store, _mask) \
+ IIO_EVENT_ATTR_SH(ring_75_full, _evlist, _show, _store, _mask)
+
+#define IIO_EVENT_CODE_RING_50_FULL IIO_EVENT_CODE_RING_BASE
+#define IIO_EVENT_CODE_RING_75_FULL (IIO_EVENT_CODE_RING_BASE + 1)
+#define IIO_EVENT_CODE_RING_100_FULL (IIO_EVENT_CODE_RING_BASE + 2)
+
+#endif /* _INDUSTRIAL_IO_SYSFS_H_ */
diff --git a/include/linux/iio/trigger_consumer.h b/include/linux/iio/trigger_consumer.h
new file mode 100644
index 0000000..a605389
--- /dev/null
+++ b/include/linux/iio/trigger_consumer.h
@@ -0,0 +1,26 @@
+
+/* The industrial I/O core, trigger consumer handling functions
+ *
+ * Copyright (c) 2008 Jonathan Cameron
+ *
+ * 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.
+ */
+
+/**
+ * iio_device_register_trigger_consumer() - set up an iio_dev to use triggers.
+ * @dev_info: iio_dev associated with the device that will consume the trigger
+ **/
+int iio_device_register_trigger_consumer(struct iio_dev *dev_info)
+{
+ return 0;
+};
+/**
+ * iio_device_unregister_trigger_consumer() - reverse the registration process
+. * @dev_info: iio_dev associated with the device that consumed the trigger
+ **/
+int iio_device_unregister_trigger_consumer(struct iio_dev *dev_info)
+{
+ return 0;
+};
--
1.6.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/