/* 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.
*/
#define pr_fmt(fmt) "iio-core: " fmt
#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>
#include <linux/iio/buffer.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",
[IIO_ALTVOLTAGE] = "altvoltage",
[IIO_CCT] = "cct",
[IIO_PRESSURE] = "pressure",
[IIO_HUMIDITYRELATIVE] = "humidityrelative",
};
static const char * const iio_modifier_names[] = {
[IIO_MOD_X] = "x",
[IIO_MOD_Y] = "y",
[IIO_MOD_Z] = "z",
[IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
[IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
[IIO_MOD_LIGHT_BOTH] = "both",
[IIO_MOD_LIGHT_IR] = "ir",
[IIO_MOD_LIGHT_CLEAR] = "clear",
[IIO_MOD_LIGHT_RED] = "red",
[IIO_MOD_LIGHT_GREEN] = "green",
[IIO_MOD_LIGHT_BLUE] = "blue",
[IIO_MOD_QUATERNION] = "quaternion",
[IIO_MOD_TEMP_AMBIENT] = "ambient",
[IIO_MOD_TEMP_OBJECT] = "object",
[IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
[IIO_MOD_NORTH_TRUE] = "from_north_true",
[IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
[IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
};
/* 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",
[IIO_CHAN_INFO_FREQUENCY] = "frequency",
[IIO_CHAN_INFO_PHASE] = "phase",
[IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
[IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
[IIO_CHAN_INFO_INT_TIME] = "integration_time",
};
/**
* iio_find_channel_from_si() - get channel from its scan index
* @indio_dev: device
* @si: scan index to match
*/
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) {
pr_err("could not register bus type\n");
goto error_nothing;
}
ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
if (ret < 0) {
pr_err("failed to allocate char dev region\n");
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 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", ®, &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 = simple_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 (!iio_debugfs_dentry)
return 0;
indio_dev->debugfs_dentry =
debugfs_create_dir(dev_name(&indio_dev->dev),
iio_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_to_iio_dev(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, ext_info->private, 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_to_iio_dev(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, ext_info->private,
this_attr->c, buf, len);
}
ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
{
const struct iio_enum *e = (const struct iio_enum *)priv;
unsigned int i;
size_t len = 0;
if (!e->num_items)
return 0;
for (i = 0; i < e->num_items; ++i)
len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
/* replace last space with a newline */
buf[len - 1] = '\n';
return len;
}
EXPORT_SYMBOL_GPL(iio_enum_available_read);
ssize_t iio_enum_read(struct iio_dev *indio_dev,
uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
{
const struct iio_enum *e = (const struct iio_enum *)priv;
int i;
if (!e->get)
return -EINVAL;
i = e->get(indio_dev, chan);
if (i < 0)
return i;
else if (i >= e->num_items)
return -EINVAL;
return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
}
EXPORT_SYMBOL_GPL(iio_enum_read);
ssize_t iio_enum_write(struct iio_dev *indio_dev,
uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
size_t len)
{
const struct iio_enum *e = (const struct iio_enum *)priv;
unsigned int i;
int ret;
if (!e->set)
return -EINVAL;
for (i = 0; i < e->num_items; i++) {
if (sysfs_streq(buf, e->items[i]))
break;
}
if (i == e->num_items)
return -EINVAL;
ret = e->set(indio_dev, chan, i);
return ret ? ret : len;
}
EXPORT_SYMBOL_GPL(iio_enum_write);
/**
* iio_format_value() - Formats a IIO value into its string representation
* @buf: The buffer to which the formated value gets written
* @type: One of the IIO_VAL_... constants. This decides how the val and val2
* parameters are formatted.
* @vals: pointer to the values, exact meaning depends on the type parameter.
*/
ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
{
unsigned long long tmp;
bool scale_db = false;
switch (type) {
case IIO_VAL_INT:
return sprintf(buf, "%d\n", vals[0]);
case IIO_VAL_INT_PLUS_MICRO_DB:
scale_db = true;
case IIO_VAL_INT_PLUS_MICRO:
if (vals[1] < 0)
return sprintf(buf, "-%ld.%06u%s\n", abs(vals[0]),
-vals[1],
scale_db ? " dB" : "");
else
return sprintf(buf, "%d.%06u%s\n", vals[0], vals[1],
scale_db ? " dB" : "");
case IIO_VAL_INT_PLUS_NANO:
if (vals[1] < 0)
return sprintf(buf, "-%ld.%09u\n", abs(vals[0]),
-vals[1]);
else
return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
case IIO_VAL_FRACTIONAL:
tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
vals[1] = do_div(tmp, 1000000000LL);
vals[0] = tmp;
return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
case IIO_VAL_FRACTIONAL_LOG2:
tmp = (s64)vals[0] * 1000000000LL >> vals[1];
vals[1] = do_div(tmp, 1000000000LL);
vals[0] = tmp;
return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
case IIO_VAL_INT_MULTIPLE:
{
int i;
int len = 0;
for (i = 0; i < size; ++i)
len += snprintf(&buf[len], PAGE_SIZE - len, "%d ",
vals[i]);
len += snprintf(&buf[len], PAGE_SIZE - len, "\n");
return len;
}
default:
return 0;
}
}
static ssize_t iio_read_channel_info(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
int vals[INDIO_MAX_RAW_ELEMENTS];
int ret;
int val_len = 2;
if (indio_dev->info->read_raw_multi)
ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
INDIO_MAX_RAW_ELEMENTS,
vals, &val_len,
this_attr->address);
else
ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
&vals[0], &vals[1], this_attr->address);
if (ret < 0)
return ret;
return iio_format_value(buf, ret, val_len, vals);
}
/**
* iio_str_to_fixpoint() - Parse a fixed-point number from a string
* @str: The string to parse
* @fract_mult: Multiplier for the first decimal place, should be a power of 10
* @integer: The integer part of the number
* @fract: The fractional part of the number
*
* Returns 0 on success, or a negative error code if the string could not be
* parsed.
*/
int iio_str_to_fixpoint(const char *str, int fract_mult,
int *integer, int *fract)
{
int i = 0, f = 0;
bool integer_part = true, negative = false;
if (str[0] == '-') {
negative = true;
str++;
} else if (str[0] == '+') {
str++;
}
while (*str) {
if ('0' <= *str && *str <= '9') {
if (integer_part) {
i = i * 10 + *str - '0';
} else {
f += fract_mult * (*str - '0');
fract_mult /= 10;
}
} else if (*str == '\n') {
if (*(str + 1) == '\0')
break;
else
return -EINVAL;
} else if (*str == '.' && integer_part) {
integer_part = false;
} else {
return -EINVAL;
}
str++;
}
if (negative) {
if (i)
i = -i;
else
f = -f;
}
*integer = i;
*fract = f;
return 0;
}
EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
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_to_iio_dev(dev);
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
int ret, fract_mult = 100000;
int integer, fract;
/* 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;
}
ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
if (ret)
return ret;
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),
enum iio_shared_by shared_by)
{
int ret = 0;
char *name = NULL;
char *full_postfix;
sysfs_attr_init(&dev_attr->attr);
/* Build up postfix of <extend_name>_<modifier>_postfix */
if (chan->modified && (shared_by == IIO_SEPARATE)) {
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 || shared_by != IIO_SEPARATE)
full_postfix = kstrdup(postfix, GFP_KERNEL);
else
full_postfix = kasprintf(GFP_KERNEL,
"%s_%s",
chan->extend_name,
postfix);
}
if (full_postfix == NULL)
return -ENOMEM;
if (chan->differential) { /* Differential can not have modifier */
switch (shared_by) {
case IIO_SHARED_BY_ALL:
name = kasprintf(GFP_KERNEL, "%s", full_postfix);
break;
case IIO_SHARED_BY_DIR:
name = kasprintf(GFP_KERNEL, "%s_%s",
iio_direction[chan->output],
full_postfix);
break;
case IIO_SHARED_BY_TYPE:
name = 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);
break;
case IIO_SEPARATE:
if (!chan->indexed) {
WARN_ON("Differential channels must be indexed\n");
ret = -EINVAL;
goto error_free_full_postfix;
}
name = 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);
break;
}
} else { /* Single ended */
switch (shared_by) {
case IIO_SHARED_BY_ALL:
name = kasprintf(GFP_KERNEL, "%s", full_postfix);
break;
case IIO_SHARED_BY_DIR:
name = kasprintf(GFP_KERNEL, "%s_%s",
iio_direction[chan->output],
full_postfix);
break;
case IIO_SHARED_BY_TYPE:
name = kasprintf(GFP_KERNEL, "%s_%s_%s",
iio_direction[chan->output],
iio_chan_type_name_spec[chan->type],
full_postfix);
break;
case IIO_SEPARATE:
if (chan->indexed)
name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
iio_direction[chan->output],
iio_chan_type_name_spec[chan->type],
chan->channel,
full_postfix);
else
name = kasprintf(GFP_KERNEL, "%s_%s_%s",
iio_direction[chan->output],
iio_chan_type_name_spec[chan->type],
full_postfix);
break;
}
}
if (name == NULL) {
ret = -ENOMEM;
goto error_free_full_postfix;
}
dev_attr->attr.name = name;
if (readfunc) {
dev_attr->attr.mode |= S_IRUGO;
dev_attr->show = readfunc;
}
if (writefunc) {
dev_attr->attr.mode |= S_IWUSR;
dev_attr->store = writefunc;
}
error_free_full_postfix:
kfree(full_postfix);
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,
enum iio_shared_by shared_by,
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)
return -ENOMEM;
ret = __iio_device_attr_init(&iio_attr->dev_attr,
postfix, chan,
readfunc, writefunc, shared_by);
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 (shared_by == IIO_SEPARATE)
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);
return ret;
}
static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
enum iio_shared_by shared_by,
const long *infomask)
{
int i, ret, attrcount = 0;
for_each_set_bit(i, infomask, sizeof(infomask)*8) {
if (i >= ARRAY_SIZE(iio_chan_info_postfix))
return -EINVAL;
ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
chan,
&iio_read_channel_info,
&iio_write_channel_info,
i,
shared_by,
&indio_dev->dev,
&indio_dev->channel_attr_list);
if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
continue;
else if (ret < 0)
return ret;
attrcount++;
}
return attrcount;
}
static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan)
{
int ret, attrcount = 0;
const struct iio_chan_spec_ext_info *ext_info;
if (chan->channel < 0)
return 0;
ret = iio_device_add_info_mask_type(indio_dev, chan,
IIO_SEPARATE,
&chan->info_mask_separate);
if (ret < 0)
return ret;
attrcount += ret;
ret = iio_device_add_info_mask_type(indio_dev, chan,
IIO_SHARED_BY_TYPE,
&chan->info_mask_shared_by_type);
if (ret < 0)
return ret;
attrcount += ret;
ret = iio_device_add_info_mask_type(indio_dev, chan,
IIO_SHARED_BY_DIR,
&chan->info_mask_shared_by_dir);
if (ret < 0)
return ret;
attrcount += ret;
ret = iio_device_add_info_mask_type(indio_dev, chan,
IIO_SHARED_BY_ALL,
&chan->info_mask_shared_by_all);
if (ret < 0)
return ret;
attrcount += ret;
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)
return ret;
attrcount++;
}
}
return attrcount;
}
/**
* iio_free_chan_devattr_list() - Free a list of IIO device attributes
* @attr_list: List of IIO device attributes
*
* This function frees the memory allocated for each of the IIO device
* attributes in the list. Note: if you want to reuse the list after calling
* this function you have to reinitialize it using INIT_LIST_HEAD().
*/
void iio_free_chan_devattr_list(struct list_head *attr_list)
{
struct iio_dev_attr *p, *n;
list_for_each_entry_safe(p, n, attr_list, l) {
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_to_iio_dev(dev);
return snprintf(buf, PAGE_SIZE, "%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;
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 its name is NULL.
*/
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:
iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
return ret;
}
static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
{
iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
kfree(indio_dev->chan_attr_group.attrs);
}
static void iio_dev_release(struct device *device)
{
struct iio_dev *indio_dev = dev_to_iio_dev(device);
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_buffer_put(indio_dev->buffer);
ida_simple_remove(&iio_ida, indio_dev->id);
kfree(indio_dev);
}
struct device_type iio_device_type = {
.name = "iio_device",
.release = iio_dev_release,
};
/**
* iio_device_alloc() - allocate an iio_dev from a driver
* @sizeof_priv: Space to allocate for private structure.
**/
struct iio_dev *iio_device_alloc(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_device_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);
INIT_LIST_HEAD(&dev->channel_attr_list);
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 */
pr_err("failed to get device id\n");
kfree(dev);
return NULL;
}
dev_set_name(&dev->dev, "iio:device%d", dev->id);
INIT_LIST_HEAD(&dev->buffer_list);
}
return dev;
}
EXPORT_SYMBOL(iio_device_alloc);
/**
* iio_device_free() - free an iio_dev from a driver
* @dev: the iio_dev associated with the device
**/
void iio_device_free(struct iio_dev *dev)
{
if (dev)
put_device(&dev->dev);
}
EXPORT_SYMBOL(iio_device_free);
static void devm_iio_device_release(struct device *dev, void *res)
{
iio_device_free(*(struct iio_dev **)res);
}
static int devm_iio_device_match(struct device *dev, void *res, void *data)
{
struct iio_dev **r = res;
if (!r || !*r) {
WARN_ON(!r || !*r);
return 0;
}
return *r == data;
}
/**
* devm_iio_device_alloc - Resource-managed iio_device_alloc()
* @dev: Device to allocate iio_dev for
* @sizeof_priv: Space to allocate for private structure.
*
* Managed iio_device_alloc. iio_dev allocated with this function is
* automatically freed on driver detach.
*
* If an iio_dev allocated with this function needs to be freed separately,
* devm_iio_device_free() must be used.
*
* RETURNS:
* Pointer to allocated iio_dev on success, NULL on failure.
*/
struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
{
struct iio_dev **ptr, *iio_dev;
ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return NULL;
/* use raw alloc_dr for kmalloc caller tracing */
iio_dev = iio_device_alloc(sizeof_priv);
if (iio_dev) {
*ptr = iio_dev;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return iio_dev;
}
EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
/**
* devm_iio_device_free - Resource-managed iio_device_free()
* @dev: Device this iio_dev belongs to
* @iio_dev: the iio_dev associated with the device
*
* Free iio_dev allocated with devm_iio_device_alloc().
*/
void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
{
int rc;
rc = devres_release(dev, devm_iio_device_release,
devm_iio_device_match, iio_dev);
WARN_ON(rc);
}
EXPORT_SYMBOL_GPL(devm_iio_device_free);
/**
* 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;
iio_device_get(indio_dev);
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);
iio_device_put(indio_dev);
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 (!indio_dev->info)
return -ENODEV;
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;
/**
* iio_device_register() - register a device with the IIO subsystem
* @indio_dev: Device structure filled by the device driver
**/
int iio_device_register(struct iio_dev *indio_dev)
{
int ret;
/* If the calling driver did not initialize of_node, do it here */
if (!indio_dev->dev.of_node && indio_dev->dev.parent)
indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
/* 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");
return 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;
cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
indio_dev->chrdev.owner = indio_dev->info->driver_module;
indio_dev->chrdev.kobj.parent = &indio_dev->dev.kobj;
ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
if (ret < 0)
goto error_unreg_eventset;
ret = device_add(&indio_dev->dev);
if (ret < 0)
goto error_cdev_del;
return 0;
error_cdev_del:
cdev_del(&indio_dev->chrdev);
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);
return ret;
}
EXPORT_SYMBOL(iio_device_register);
/**
* iio_device_unregister() - unregister a device from the IIO subsystem
* @indio_dev: Device structure representing the device.
**/
void iio_device_unregister(struct iio_dev *indio_dev)
{
mutex_lock(&indio_dev->info_exist_lock);
device_del(&indio_dev->dev);
if (indio_dev->chrdev.dev)
cdev_del(&indio_dev->chrdev);
iio_device_unregister_debugfs(indio_dev);
iio_disable_all_buffers(indio_dev);
indio_dev->info = NULL;
iio_device_wakeup_eventset(indio_dev);
iio_buffer_wakeup_poll(indio_dev);
mutex_unlock(&indio_dev->info_exist_lock);
}
EXPORT_SYMBOL(iio_device_unregister);
static void devm_iio_device_unreg(struct device *dev, void *res)
{
iio_device_unregister(*(struct iio_dev **)res);
}
/**
* devm_iio_device_register - Resource-managed iio_device_register()
* @dev: Device to allocate iio_dev for
* @indio_dev: Device structure filled by the device driver
*
* Managed iio_device_register. The IIO device registered with this
* function is automatically unregistered on driver detach. This function
* calls iio_device_register() internally. Refer to that function for more
* information.
*
* If an iio_dev registered with this function needs to be unregistered
* separately, devm_iio_device_unregister() must be used.
*
* RETURNS:
* 0 on success, negative error number on failure.
*/
int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev)
{
struct iio_dev **ptr;
int ret;
ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return -ENOMEM;
*ptr = indio_dev;
ret = iio_device_register(indio_dev);
if (!ret)
devres_add(dev, ptr);
else
devres_free(ptr);
return ret;
}
EXPORT_SYMBOL_GPL(devm_iio_device_register);
/**
* devm_iio_device_unregister - Resource-managed iio_device_unregister()
* @dev: Device this iio_dev belongs to
* @indio_dev: the iio_dev associated with the device
*
* Unregister iio_dev registered with devm_iio_device_register().
*/
void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
{
int rc;
rc = devres_release(dev, devm_iio_device_unreg,
devm_iio_device_match, indio_dev);
WARN_ON(rc);
}
EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
subsys_initcall(iio_init);
module_exit(iio_exit);
MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
MODULE_DESCRIPTION("Industrial I/O core");
MODULE_LICENSE("GPL");