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authorJonathan Cameron <jic23@kernel.org>2012-04-25 15:54:59 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-04-25 11:11:38 -0700
commita980e046098b0a40eaff5e4e7fcde6cf035b7c06 (patch)
tree23375fc2bba39f088974cf621f7abf006d43d087 /drivers/iio/industrialio-core.c
parent06458e277eac2b8761b0a04d3c808d57be281a2e (diff)
IIO: Move the core files to drivers/iio
Take the core support + the kfifo buffer implentation out of staging. Whilst we are far from done in improving this subsystem it is now at a stage where the userspae interfaces (provided by the core) can be considered stable. Drivers will follow over a longer time scale. Signed-off-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iio/industrialio-core.c')
-rw-r--r--drivers/iio/industrialio-core.c912
1 files changed, 912 insertions, 0 deletions
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
new file mode 100644
index 000000000000..dd1a6a2e81c0
--- /dev/null
+++ b/drivers/iio/industrialio-core.c
@@ -0,0 +1,912 @@
+/* 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/poll.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/cdev.h>
+#include <linux/slab.h>
+#include <linux/anon_inodes.h>
+#include <linux/debugfs.h>
+#include <linux/iio/iio.h>
+#include "iio_core.h"
+#include "iio_core_trigger.h"
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+
+/* IDA to assign each registered device a unique id*/
+static DEFINE_IDA(iio_ida);
+
+static dev_t iio_devt;
+
+#define IIO_DEV_MAX 256
+struct bus_type iio_bus_type = {
+ .name = "iio",
+};
+EXPORT_SYMBOL(iio_bus_type);
+
+static struct dentry *iio_debugfs_dentry;
+
+static const char * const iio_direction[] = {
+ [0] = "in",
+ [1] = "out",
+};
+
+static const char * const iio_chan_type_name_spec[] = {
+ [IIO_VOLTAGE] = "voltage",
+ [IIO_CURRENT] = "current",
+ [IIO_POWER] = "power",
+ [IIO_ACCEL] = "accel",
+ [IIO_ANGL_VEL] = "anglvel",
+ [IIO_MAGN] = "magn",
+ [IIO_LIGHT] = "illuminance",
+ [IIO_INTENSITY] = "intensity",
+ [IIO_PROXIMITY] = "proximity",
+ [IIO_TEMP] = "temp",
+ [IIO_INCLI] = "incli",
+ [IIO_ROT] = "rot",
+ [IIO_ANGL] = "angl",
+ [IIO_TIMESTAMP] = "timestamp",
+ [IIO_CAPACITANCE] = "capacitance",
+};
+
+static const char * const iio_modifier_names[] = {
+ [IIO_MOD_X] = "x",
+ [IIO_MOD_Y] = "y",
+ [IIO_MOD_Z] = "z",
+ [IIO_MOD_LIGHT_BOTH] = "both",
+ [IIO_MOD_LIGHT_IR] = "ir",
+};
+
+/* relies on pairs of these shared then separate */
+static const char * const iio_chan_info_postfix[] = {
+ [IIO_CHAN_INFO_RAW] = "raw",
+ [IIO_CHAN_INFO_PROCESSED] = "input",
+ [IIO_CHAN_INFO_SCALE] = "scale",
+ [IIO_CHAN_INFO_OFFSET] = "offset",
+ [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
+ [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
+ [IIO_CHAN_INFO_PEAK] = "peak_raw",
+ [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
+ [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
+ [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
+ [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
+ = "filter_low_pass_3db_frequency",
+ [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
+};
+
+const struct iio_chan_spec
+*iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
+{
+ int i;
+
+ for (i = 0; i < indio_dev->num_channels; i++)
+ if (indio_dev->channels[i].scan_index == si)
+ return &indio_dev->channels[i];
+ return NULL;
+}
+
+/* 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);
+
+static int __init iio_init(void)
+{
+ int ret;
+
+ /* Register sysfs bus */
+ ret = bus_register(&iio_bus_type);
+ if (ret < 0) {
+ printk(KERN_ERR
+ "%s could not register bus type\n",
+ __FILE__);
+ goto error_nothing;
+ }
+
+ ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
+ if (ret < 0) {
+ printk(KERN_ERR "%s: failed to allocate char dev region\n",
+ __FILE__);
+ goto error_unregister_bus_type;
+ }
+
+ iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
+
+ return 0;
+
+error_unregister_bus_type:
+ bus_unregister(&iio_bus_type);
+error_nothing:
+ return ret;
+}
+
+static void __exit iio_exit(void)
+{
+ if (iio_devt)
+ unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
+ bus_unregister(&iio_bus_type);
+ debugfs_remove(iio_debugfs_dentry);
+}
+
+#if defined(CONFIG_DEBUG_FS)
+static int iio_debugfs_open(struct inode *inode, struct file *file)
+{
+ if (inode->i_private)
+ file->private_data = inode->i_private;
+
+ return 0;
+}
+
+static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct iio_dev *indio_dev = file->private_data;
+ char buf[20];
+ unsigned val = 0;
+ ssize_t len;
+ int ret;
+
+ ret = indio_dev->info->debugfs_reg_access(indio_dev,
+ indio_dev->cached_reg_addr,
+ 0, &val);
+ if (ret)
+ dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
+
+ len = snprintf(buf, sizeof(buf), "0x%X\n", val);
+
+ return simple_read_from_buffer(userbuf, count, ppos, buf, len);
+}
+
+static ssize_t iio_debugfs_write_reg(struct file *file,
+ const char __user *userbuf, size_t count, loff_t *ppos)
+{
+ struct iio_dev *indio_dev = file->private_data;
+ unsigned reg, val;
+ char buf[80];
+ int ret;
+
+ count = min_t(size_t, count, (sizeof(buf)-1));
+ if (copy_from_user(buf, userbuf, count))
+ return -EFAULT;
+
+ buf[count] = 0;
+
+ ret = sscanf(buf, "%i %i", &reg, &val);
+
+ switch (ret) {
+ case 1:
+ indio_dev->cached_reg_addr = reg;
+ break;
+ case 2:
+ indio_dev->cached_reg_addr = reg;
+ ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
+ val, NULL);
+ if (ret) {
+ dev_err(indio_dev->dev.parent, "%s: write failed\n",
+ __func__);
+ return ret;
+ }
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return count;
+}
+
+static const struct file_operations iio_debugfs_reg_fops = {
+ .open = iio_debugfs_open,
+ .read = iio_debugfs_read_reg,
+ .write = iio_debugfs_write_reg,
+};
+
+static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
+{
+ debugfs_remove_recursive(indio_dev->debugfs_dentry);
+}
+
+static int iio_device_register_debugfs(struct iio_dev *indio_dev)
+{
+ struct dentry *d;
+
+ if (indio_dev->info->debugfs_reg_access == NULL)
+ return 0;
+
+ if (IS_ERR(iio_debugfs_dentry))
+ return 0;
+
+ indio_dev->debugfs_dentry =
+ debugfs_create_dir(dev_name(&indio_dev->dev),
+ iio_debugfs_dentry);
+ if (IS_ERR(indio_dev->debugfs_dentry))
+ return PTR_ERR(indio_dev->debugfs_dentry);
+
+ if (indio_dev->debugfs_dentry == NULL) {
+ dev_warn(indio_dev->dev.parent,
+ "Failed to create debugfs directory\n");
+ return -EFAULT;
+ }
+
+ d = debugfs_create_file("direct_reg_access", 0644,
+ indio_dev->debugfs_dentry,
+ indio_dev, &iio_debugfs_reg_fops);
+ if (!d) {
+ iio_device_unregister_debugfs(indio_dev);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+#else
+static int iio_device_register_debugfs(struct iio_dev *indio_dev)
+{
+ return 0;
+}
+
+static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
+static ssize_t iio_read_channel_ext_info(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ ext_info = &this_attr->c->ext_info[this_attr->address];
+
+ return ext_info->read(indio_dev, this_attr->c, buf);
+}
+
+static ssize_t iio_write_channel_ext_info(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ ext_info = &this_attr->c->ext_info[this_attr->address];
+
+ return ext_info->write(indio_dev, this_attr->c, buf, len);
+}
+
+static ssize_t iio_read_channel_info(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ int val, val2;
+ int ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
+ &val, &val2, this_attr->address);
+
+ if (ret < 0)
+ return ret;
+
+ if (ret == IIO_VAL_INT)
+ return sprintf(buf, "%d\n", val);
+ else if (ret == IIO_VAL_INT_PLUS_MICRO) {
+ if (val2 < 0)
+ return sprintf(buf, "-%d.%06u\n", val, -val2);
+ else
+ return sprintf(buf, "%d.%06u\n", val, val2);
+ } else if (ret == IIO_VAL_INT_PLUS_NANO) {
+ if (val2 < 0)
+ return sprintf(buf, "-%d.%09u\n", val, -val2);
+ else
+ return sprintf(buf, "%d.%09u\n", val, val2);
+ } else
+ return 0;
+}
+
+static ssize_t iio_write_channel_info(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ int ret, integer = 0, fract = 0, fract_mult = 100000;
+ bool integer_part = true, negative = false;
+
+ /* Assumes decimal - precision based on number of digits */
+ if (!indio_dev->info->write_raw)
+ return -EINVAL;
+
+ if (indio_dev->info->write_raw_get_fmt)
+ switch (indio_dev->info->write_raw_get_fmt(indio_dev,
+ this_attr->c, this_attr->address)) {
+ case IIO_VAL_INT_PLUS_MICRO:
+ fract_mult = 100000;
+ break;
+ case IIO_VAL_INT_PLUS_NANO:
+ fract_mult = 100000000;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (buf[0] == '-') {
+ negative = true;
+ buf++;
+ }
+
+ while (*buf) {
+ if ('0' <= *buf && *buf <= '9') {
+ if (integer_part)
+ integer = integer*10 + *buf - '0';
+ else {
+ fract += fract_mult*(*buf - '0');
+ if (fract_mult == 1)
+ break;
+ fract_mult /= 10;
+ }
+ } else if (*buf == '\n') {
+ if (*(buf + 1) == '\0')
+ break;
+ else
+ return -EINVAL;
+ } else if (*buf == '.') {
+ integer_part = false;
+ } else {
+ return -EINVAL;
+ }
+ buf++;
+ }
+ if (negative) {
+ if (integer)
+ integer = -integer;
+ else
+ fract = -fract;
+ }
+
+ ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
+ integer, fract, this_attr->address);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static
+int __iio_device_attr_init(struct device_attribute *dev_attr,
+ const char *postfix,
+ struct iio_chan_spec const *chan,
+ ssize_t (*readfunc)(struct device *dev,
+ struct device_attribute *attr,
+ char *buf),
+ ssize_t (*writefunc)(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len),
+ bool generic)
+{
+ int ret;
+ char *name_format, *full_postfix;
+ sysfs_attr_init(&dev_attr->attr);
+
+ /* Build up postfix of <extend_name>_<modifier>_postfix */
+ if (chan->modified && !generic) {
+ if (chan->extend_name)
+ full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
+ iio_modifier_names[chan
+ ->channel2],
+ chan->extend_name,
+ postfix);
+ else
+ full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
+ iio_modifier_names[chan
+ ->channel2],
+ postfix);
+ } else {
+ if (chan->extend_name == NULL)
+ full_postfix = kstrdup(postfix, GFP_KERNEL);
+ else
+ full_postfix = kasprintf(GFP_KERNEL,
+ "%s_%s",
+ chan->extend_name,
+ postfix);
+ }
+ if (full_postfix == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+
+ if (chan->differential) { /* Differential can not have modifier */
+ if (generic)
+ name_format
+ = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
+ iio_direction[chan->output],
+ iio_chan_type_name_spec[chan->type],
+ iio_chan_type_name_spec[chan->type],
+ full_postfix);
+ else if (chan->indexed)
+ name_format
+ = kasprintf(GFP_KERNEL, "%s_%s%d-%s%d_%s",
+ iio_direction[chan->output],
+ iio_chan_type_name_spec[chan->type],
+ chan->channel,
+ iio_chan_type_name_spec[chan->type],
+ chan->channel2,
+ full_postfix);
+ else {
+ WARN_ON("Differential channels must be indexed\n");
+ ret = -EINVAL;
+ goto error_free_full_postfix;
+ }
+ } else { /* Single ended */
+ if (generic)
+ name_format
+ = kasprintf(GFP_KERNEL, "%s_%s_%s",
+ iio_direction[chan->output],
+ iio_chan_type_name_spec[chan->type],
+ full_postfix);
+ else if (chan->indexed)
+ name_format
+ = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
+ iio_direction[chan->output],
+ iio_chan_type_name_spec[chan->type],
+ chan->channel,
+ full_postfix);
+ else
+ name_format
+ = kasprintf(GFP_KERNEL, "%s_%s_%s",
+ iio_direction[chan->output],
+ iio_chan_type_name_spec[chan->type],
+ full_postfix);
+ }
+ if (name_format == NULL) {
+ ret = -ENOMEM;
+ goto error_free_full_postfix;
+ }
+ dev_attr->attr.name = kasprintf(GFP_KERNEL,
+ name_format,
+ chan->channel,
+ chan->channel2);
+ if (dev_attr->attr.name == NULL) {
+ ret = -ENOMEM;
+ goto error_free_name_format;
+ }
+
+ if (readfunc) {
+ dev_attr->attr.mode |= S_IRUGO;
+ dev_attr->show = readfunc;
+ }
+
+ if (writefunc) {
+ dev_attr->attr.mode |= S_IWUSR;
+ dev_attr->store = writefunc;
+ }
+ kfree(name_format);
+ kfree(full_postfix);
+
+ return 0;
+
+error_free_name_format:
+ kfree(name_format);
+error_free_full_postfix:
+ kfree(full_postfix);
+error_ret:
+ return ret;
+}
+
+static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
+{
+ kfree(dev_attr->attr.name);
+}
+
+int __iio_add_chan_devattr(const char *postfix,
+ struct iio_chan_spec const *chan,
+ ssize_t (*readfunc)(struct device *dev,
+ struct device_attribute *attr,
+ char *buf),
+ ssize_t (*writefunc)(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len),
+ u64 mask,
+ bool generic,
+ struct device *dev,
+ struct list_head *attr_list)
+{
+ int ret;
+ struct iio_dev_attr *iio_attr, *t;
+
+ iio_attr = kzalloc(sizeof *iio_attr, GFP_KERNEL);
+ if (iio_attr == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ ret = __iio_device_attr_init(&iio_attr->dev_attr,
+ postfix, chan,
+ readfunc, writefunc, generic);
+ if (ret)
+ goto error_iio_dev_attr_free;
+ iio_attr->c = chan;
+ iio_attr->address = mask;
+ list_for_each_entry(t, attr_list, l)
+ if (strcmp(t->dev_attr.attr.name,
+ iio_attr->dev_attr.attr.name) == 0) {
+ if (!generic)
+ dev_err(dev, "tried to double register : %s\n",
+ t->dev_attr.attr.name);
+ ret = -EBUSY;
+ goto error_device_attr_deinit;
+ }
+ list_add(&iio_attr->l, attr_list);
+
+ return 0;
+
+error_device_attr_deinit:
+ __iio_device_attr_deinit(&iio_attr->dev_attr);
+error_iio_dev_attr_free:
+ kfree(iio_attr);
+error_ret:
+ return ret;
+}
+
+static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan)
+{
+ int ret, attrcount = 0;
+ int i;
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ if (chan->channel < 0)
+ return 0;
+ for_each_set_bit(i, &chan->info_mask, sizeof(long)*8) {
+ ret = __iio_add_chan_devattr(iio_chan_info_postfix[i/2],
+ chan,
+ &iio_read_channel_info,
+ &iio_write_channel_info,
+ i/2,
+ !(i%2),
+ &indio_dev->dev,
+ &indio_dev->channel_attr_list);
+ if (ret == -EBUSY && (i%2 == 0)) {
+ ret = 0;
+ continue;
+ }
+ if (ret < 0)
+ goto error_ret;
+ attrcount++;
+ }
+
+ if (chan->ext_info) {
+ unsigned int i = 0;
+ for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
+ ret = __iio_add_chan_devattr(ext_info->name,
+ chan,
+ ext_info->read ?
+ &iio_read_channel_ext_info : NULL,
+ ext_info->write ?
+ &iio_write_channel_ext_info : NULL,
+ i,
+ ext_info->shared,
+ &indio_dev->dev,
+ &indio_dev->channel_attr_list);
+ i++;
+ if (ret == -EBUSY && ext_info->shared)
+ continue;
+
+ if (ret)
+ goto error_ret;
+
+ attrcount++;
+ }
+ }
+
+ ret = attrcount;
+error_ret:
+ return ret;
+}
+
+static void iio_device_remove_and_free_read_attr(struct iio_dev *indio_dev,
+ struct iio_dev_attr *p)
+{
+ kfree(p->dev_attr.attr.name);
+ kfree(p);
+}
+
+static ssize_t iio_show_dev_name(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ return sprintf(buf, "%s\n", indio_dev->name);
+}
+
+static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
+
+static int iio_device_register_sysfs(struct iio_dev *indio_dev)
+{
+ int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
+ struct iio_dev_attr *p, *n;
+ struct attribute **attr;
+
+ /* First count elements in any existing group */
+ if (indio_dev->info->attrs) {
+ attr = indio_dev->info->attrs->attrs;
+ while (*attr++ != NULL)
+ attrcount_orig++;
+ }
+ attrcount = attrcount_orig;
+ /*
+ * New channel registration method - relies on the fact a group does
+ * not need to be initialized if it is name is NULL.
+ */
+ INIT_LIST_HEAD(&indio_dev->channel_attr_list);
+ if (indio_dev->channels)
+ for (i = 0; i < indio_dev->num_channels; i++) {
+ ret = iio_device_add_channel_sysfs(indio_dev,
+ &indio_dev
+ ->channels[i]);
+ if (ret < 0)
+ goto error_clear_attrs;
+ attrcount += ret;
+ }
+
+ if (indio_dev->name)
+ attrcount++;
+
+ indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
+ sizeof(indio_dev->chan_attr_group.attrs[0]),
+ GFP_KERNEL);
+ if (indio_dev->chan_attr_group.attrs == NULL) {
+ ret = -ENOMEM;
+ goto error_clear_attrs;
+ }
+ /* Copy across original attributes */
+ if (indio_dev->info->attrs)
+ memcpy(indio_dev->chan_attr_group.attrs,
+ indio_dev->info->attrs->attrs,
+ sizeof(indio_dev->chan_attr_group.attrs[0])
+ *attrcount_orig);
+ attrn = attrcount_orig;
+ /* Add all elements from the list. */
+ list_for_each_entry(p, &indio_dev->channel_attr_list, l)
+ indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
+ if (indio_dev->name)
+ indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
+
+ indio_dev->groups[indio_dev->groupcounter++] =
+ &indio_dev->chan_attr_group;
+
+ return 0;
+
+error_clear_attrs:
+ list_for_each_entry_safe(p, n,
+ &indio_dev->channel_attr_list, l) {
+ list_del(&p->l);
+ iio_device_remove_and_free_read_attr(indio_dev, p);
+ }
+
+ return ret;
+}
+
+static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
+{
+
+ struct iio_dev_attr *p, *n;
+
+ list_for_each_entry_safe(p, n, &indio_dev->channel_attr_list, l) {
+ list_del(&p->l);
+ iio_device_remove_and_free_read_attr(indio_dev, p);
+ }
+ kfree(indio_dev->chan_attr_group.attrs);
+}
+
+static void iio_dev_release(struct device *device)
+{
+ struct iio_dev *indio_dev = container_of(device, struct iio_dev, dev);
+ cdev_del(&indio_dev->chrdev);
+ if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
+ iio_device_unregister_trigger_consumer(indio_dev);
+ iio_device_unregister_eventset(indio_dev);
+ iio_device_unregister_sysfs(indio_dev);
+ iio_device_unregister_debugfs(indio_dev);
+}
+
+static struct device_type iio_dev_type = {
+ .name = "iio_device",
+ .release = iio_dev_release,
+};
+
+struct iio_dev *iio_allocate_device(int sizeof_priv)
+{
+ struct iio_dev *dev;
+ size_t alloc_size;
+
+ alloc_size = sizeof(struct iio_dev);
+ if (sizeof_priv) {
+ alloc_size = ALIGN(alloc_size, IIO_ALIGN);
+ alloc_size += sizeof_priv;
+ }
+ /* ensure 32-byte alignment of whole construct ? */
+ alloc_size += IIO_ALIGN - 1;
+
+ dev = kzalloc(alloc_size, GFP_KERNEL);
+
+ if (dev) {
+ dev->dev.groups = dev->groups;
+ dev->dev.type = &iio_dev_type;
+ dev->dev.bus = &iio_bus_type;
+ device_initialize(&dev->dev);
+ dev_set_drvdata(&dev->dev, (void *)dev);
+ mutex_init(&dev->mlock);
+ mutex_init(&dev->info_exist_lock);
+
+ dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
+ if (dev->id < 0) {
+ /* cannot use a dev_err as the name isn't available */
+ printk(KERN_ERR "Failed to get id\n");
+ kfree(dev);
+ return NULL;
+ }
+ dev_set_name(&dev->dev, "iio:device%d", dev->id);
+ }
+
+ return dev;
+}
+EXPORT_SYMBOL(iio_allocate_device);
+
+void iio_free_device(struct iio_dev *dev)
+{
+ if (dev) {
+ ida_simple_remove(&iio_ida, dev->id);
+ kfree(dev);
+ }
+}
+EXPORT_SYMBOL(iio_free_device);
+
+/**
+ * iio_chrdev_open() - chrdev file open for buffer access and ioctls
+ **/
+static int iio_chrdev_open(struct inode *inode, struct file *filp)
+{
+ struct iio_dev *indio_dev = container_of(inode->i_cdev,
+ struct iio_dev, chrdev);
+
+ if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
+ return -EBUSY;
+
+ filp->private_data = indio_dev;
+
+ return 0;
+}
+
+/**
+ * iio_chrdev_release() - chrdev file close buffer access and ioctls
+ **/
+static int iio_chrdev_release(struct inode *inode, struct file *filp)
+{
+ struct iio_dev *indio_dev = container_of(inode->i_cdev,
+ struct iio_dev, chrdev);
+ clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
+ return 0;
+}
+
+/* Somewhat of a cross file organization violation - ioctls here are actually
+ * event related */
+static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+ struct iio_dev *indio_dev = filp->private_data;
+ int __user *ip = (int __user *)arg;
+ int fd;
+
+ if (cmd == IIO_GET_EVENT_FD_IOCTL) {
+ fd = iio_event_getfd(indio_dev);
+ if (copy_to_user(ip, &fd, sizeof(fd)))
+ return -EFAULT;
+ return 0;
+ }
+ return -EINVAL;
+}
+
+static const struct file_operations iio_buffer_fileops = {
+ .read = iio_buffer_read_first_n_outer_addr,
+ .release = iio_chrdev_release,
+ .open = iio_chrdev_open,
+ .poll = iio_buffer_poll_addr,
+ .owner = THIS_MODULE,
+ .llseek = noop_llseek,
+ .unlocked_ioctl = iio_ioctl,
+ .compat_ioctl = iio_ioctl,
+};
+
+static const struct iio_buffer_setup_ops noop_ring_setup_ops;
+
+int iio_device_register(struct iio_dev *indio_dev)
+{
+ int ret;
+
+ /* configure elements for the chrdev */
+ indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
+
+ ret = iio_device_register_debugfs(indio_dev);
+ if (ret) {
+ dev_err(indio_dev->dev.parent,
+ "Failed to register debugfs interfaces\n");
+ goto error_ret;
+ }
+ ret = iio_device_register_sysfs(indio_dev);
+ if (ret) {
+ dev_err(indio_dev->dev.parent,
+ "Failed to register sysfs interfaces\n");
+ goto error_unreg_debugfs;
+ }
+ ret = iio_device_register_eventset(indio_dev);
+ if (ret) {
+ dev_err(indio_dev->dev.parent,
+ "Failed to register event set\n");
+ goto error_free_sysfs;
+ }
+ if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
+ iio_device_register_trigger_consumer(indio_dev);
+
+ if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
+ indio_dev->setup_ops == NULL)
+ indio_dev->setup_ops = &noop_ring_setup_ops;
+
+ ret = device_add(&indio_dev->dev);
+ if (ret < 0)
+ goto error_unreg_eventset;
+ cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
+ indio_dev->chrdev.owner = indio_dev->info->driver_module;
+ ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
+ if (ret < 0)
+ goto error_del_device;
+ return 0;
+
+error_del_device:
+ device_del(&indio_dev->dev);
+error_unreg_eventset:
+ iio_device_unregister_eventset(indio_dev);
+error_free_sysfs:
+ iio_device_unregister_sysfs(indio_dev);
+error_unreg_debugfs:
+ iio_device_unregister_debugfs(indio_dev);
+error_ret:
+ return ret;
+}
+EXPORT_SYMBOL(iio_device_register);
+
+void iio_device_unregister(struct iio_dev *indio_dev)
+{
+ mutex_lock(&indio_dev->info_exist_lock);
+ indio_dev->info = NULL;
+ mutex_unlock(&indio_dev->info_exist_lock);
+ device_unregister(&indio_dev->dev);
+}
+EXPORT_SYMBOL(iio_device_unregister);
+subsys_initcall(iio_init);
+module_exit(iio_exit);
+
+MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
+MODULE_DESCRIPTION("Industrial I/O core");
+MODULE_LICENSE("GPL");