linux/drivers/iio/industrialio-core.c
Jonathan Cameron 5123960007 iio:core: add a callback to allow drivers to provide _available attributes
A large number of attributes can only take a limited range of values.
Currently in IIO this is handled by directly registering additional
*_available attributes thus providing this information to userspace.

It is desirable to provide this information via the core for much the same
reason this was done for the actual channel information attributes in the
first place.  If it isn't there, then it can only really be accessed from
userspace.  Other in kernel IIO consumers have no access to what valid
parameters are.

Two forms are currently supported:
* list of values in one particular IIO_VAL_* format.
	e.g. 1.300000 1.500000 1.730000
* range specification with a step size:
	e.g. [1.000000 0.500000 2.500000]
	equivalent to 1.000000 1.5000000 2.000000 2.500000

An addition set of masks are used to allow different sharing rules for the
*_available attributes generated.

This allows for example:

in_accel_x_offset
in_accel_y_offset
in_accel_offset_available.

We could have gone with having a specification for each and every
info_mask element but that would have meant changing the existing userspace
ABI.  This approach does not.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
[forward ported, added some docs and fixed buffer overflows /peda]
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-11-13 11:40:25 +00:00

1874 lines
46 KiB
C

/* 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/mutex.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",
[IIO_ACTIVITY] = "activity",
[IIO_STEPS] = "steps",
[IIO_ENERGY] = "energy",
[IIO_DISTANCE] = "distance",
[IIO_VELOCITY] = "velocity",
[IIO_CONCENTRATION] = "concentration",
[IIO_RESISTANCE] = "resistance",
[IIO_PH] = "ph",
[IIO_UVINDEX] = "uvindex",
[IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",
[IIO_COUNT] = "count",
[IIO_INDEX] = "index",
};
static const char * const iio_modifier_names[] = {
[IIO_MOD_X] = "x",
[IIO_MOD_Y] = "y",
[IIO_MOD_Z] = "z",
[IIO_MOD_X_AND_Y] = "x&y",
[IIO_MOD_X_AND_Z] = "x&z",
[IIO_MOD_Y_AND_Z] = "y&z",
[IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
[IIO_MOD_X_OR_Y] = "x|y",
[IIO_MOD_X_OR_Z] = "x|z",
[IIO_MOD_Y_OR_Z] = "y|z",
[IIO_MOD_X_OR_Y_OR_Z] = "x|y|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_LIGHT_UV] = "uv",
[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",
[IIO_MOD_RUNNING] = "running",
[IIO_MOD_JOGGING] = "jogging",
[IIO_MOD_WALKING] = "walking",
[IIO_MOD_STILL] = "still",
[IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
[IIO_MOD_I] = "i",
[IIO_MOD_Q] = "q",
[IIO_MOD_CO2] = "co2",
[IIO_MOD_VOC] = "voc",
};
/* 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_HIGH_PASS_FILTER_3DB_FREQUENCY]
= "filter_high_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_CHAN_INFO_ENABLE] = "en",
[IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
[IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
[IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
[IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
[IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
[IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
};
/**
* 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 iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id)
{
int ret;
const struct iio_event_interface *ev_int = indio_dev->event_interface;
ret = mutex_lock_interruptible(&indio_dev->mlock);
if (ret)
return ret;
if ((ev_int && iio_event_enabled(ev_int)) ||
iio_buffer_enabled(indio_dev)) {
mutex_unlock(&indio_dev->mlock);
return -EBUSY;
}
indio_dev->clock_id = clock_id;
mutex_unlock(&indio_dev->mlock);
return 0;
}
/**
* iio_get_time_ns() - utility function to get a time stamp for events etc
* @indio_dev: device
*/
s64 iio_get_time_ns(const struct iio_dev *indio_dev)
{
struct timespec tp;
switch (iio_device_get_clock(indio_dev)) {
case CLOCK_REALTIME:
ktime_get_real_ts(&tp);
break;
case CLOCK_MONOTONIC:
ktime_get_ts(&tp);
break;
case CLOCK_MONOTONIC_RAW:
getrawmonotonic(&tp);
break;
case CLOCK_REALTIME_COARSE:
tp = current_kernel_time();
break;
case CLOCK_MONOTONIC_COARSE:
tp = get_monotonic_coarse();
break;
case CLOCK_BOOTTIME:
get_monotonic_boottime(&tp);
break;
case CLOCK_TAI:
timekeeping_clocktai(&tp);
break;
default:
BUG();
}
return timespec_to_ns(&tp);
}
EXPORT_SYMBOL(iio_get_time_ns);
/**
* iio_get_time_res() - utility function to get time stamp clock resolution in
* nano seconds.
* @indio_dev: device
*/
unsigned int iio_get_time_res(const struct iio_dev *indio_dev)
{
switch (iio_device_get_clock(indio_dev)) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_MONOTONIC_RAW:
case CLOCK_BOOTTIME:
case CLOCK_TAI:
return hrtimer_resolution;
case CLOCK_REALTIME_COARSE:
case CLOCK_MONOTONIC_COARSE:
return LOW_RES_NSEC;
default:
BUG();
}
}
EXPORT_SYMBOL(iio_get_time_res);
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", &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 = 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);
static const struct iio_mount_matrix iio_mount_idmatrix = {
.rotation = {
"1", "0", "0",
"0", "1", "0",
"0", "0", "1"
}
};
static int iio_setup_mount_idmatrix(const struct device *dev,
struct iio_mount_matrix *matrix)
{
*matrix = iio_mount_idmatrix;
dev_info(dev, "mounting matrix not found: using identity...\n");
return 0;
}
ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
const struct iio_chan_spec *chan, char *buf)
{
const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
priv)(indio_dev, chan);
if (IS_ERR(mtx))
return PTR_ERR(mtx);
if (!mtx)
mtx = &iio_mount_idmatrix;
return snprintf(buf, PAGE_SIZE, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
}
EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
/**
* of_iio_read_mount_matrix() - retrieve iio device mounting matrix from
* device-tree "mount-matrix" property
* @dev: device the mounting matrix property is assigned to
* @propname: device specific mounting matrix property name
* @matrix: where to store retrieved matrix
*
* If device is assigned no mounting matrix property, a default 3x3 identity
* matrix will be filled in.
*
* Return: 0 if success, or a negative error code on failure.
*/
#ifdef CONFIG_OF
int of_iio_read_mount_matrix(const struct device *dev,
const char *propname,
struct iio_mount_matrix *matrix)
{
if (dev->of_node) {
int err = of_property_read_string_array(dev->of_node,
propname, matrix->rotation,
ARRAY_SIZE(iio_mount_idmatrix.rotation));
if (err == ARRAY_SIZE(iio_mount_idmatrix.rotation))
return 0;
if (err >= 0)
/* Invalid number of matrix entries. */
return -EINVAL;
if (err != -EINVAL)
/* Invalid matrix declaration format. */
return err;
}
/* Matrix was not declared at all: fallback to identity. */
return iio_setup_mount_idmatrix(dev, matrix);
}
#else
int of_iio_read_mount_matrix(const struct device *dev,
const char *propname,
struct iio_mount_matrix *matrix)
{
return iio_setup_mount_idmatrix(dev, matrix);
}
#endif
EXPORT_SYMBOL(of_iio_read_mount_matrix);
static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
int size, const int *vals)
{
unsigned long long tmp;
int tmp0, tmp1;
bool scale_db = false;
switch (type) {
case IIO_VAL_INT:
return snprintf(buf, len, "%d", vals[0]);
case IIO_VAL_INT_PLUS_MICRO_DB:
scale_db = true;
case IIO_VAL_INT_PLUS_MICRO:
if (vals[1] < 0)
return snprintf(buf, len, "-%d.%06u%s", abs(vals[0]),
-vals[1], scale_db ? " dB" : "");
else
return snprintf(buf, len, "%d.%06u%s", vals[0], vals[1],
scale_db ? " dB" : "");
case IIO_VAL_INT_PLUS_NANO:
if (vals[1] < 0)
return snprintf(buf, len, "-%d.%09u", abs(vals[0]),
-vals[1]);
else
return snprintf(buf, len, "%d.%09u", vals[0], vals[1]);
case IIO_VAL_FRACTIONAL:
tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
tmp1 = vals[1];
tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
case IIO_VAL_FRACTIONAL_LOG2:
tmp = (s64)vals[0] * 1000000000LL >> vals[1];
tmp1 = do_div(tmp, 1000000000LL);
tmp0 = tmp;
return snprintf(buf, len, "%d.%09u", tmp0, tmp1);
case IIO_VAL_INT_MULTIPLE:
{
int i;
int l = 0;
for (i = 0; i < size; ++i) {
l += snprintf(&buf[l], len - l, "%d ", vals[i]);
if (l >= len)
break;
}
return l;
}
default:
return 0;
}
}
/**
* iio_format_value() - Formats a IIO value into its string representation
* @buf: The buffer to which the formatted value gets written
* which is assumed to be big enough (i.e. PAGE_SIZE).
* @type: One of the IIO_VAL_... constants. This decides how the val
* and val2 parameters are formatted.
* @size: Number of IIO value entries contained in vals
* @vals: Pointer to the values, exact meaning depends on the
* type parameter.
*
* Return: 0 by default, a negative number on failure or the
* total number of characters written for a type that belongs
* to the IIO_VAL_... constant.
*/
ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
{
ssize_t len;
len = __iio_format_value(buf, PAGE_SIZE, type, size, vals);
if (len >= PAGE_SIZE - 1)
return -EFBIG;
return len + sprintf(buf + len, "\n");
}
EXPORT_SYMBOL_GPL(iio_format_value);
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);
}
static ssize_t iio_format_avail_list(char *buf, const int *vals,
int type, int length)
{
int i;
ssize_t len = 0;
switch (type) {
case IIO_VAL_INT:
for (i = 0; i < length; i++) {
len += __iio_format_value(buf + len, PAGE_SIZE - len,
type, 1, &vals[i]);
if (len >= PAGE_SIZE)
return -EFBIG;
if (i < length - 1)
len += snprintf(buf + len, PAGE_SIZE - len,
" ");
else
len += snprintf(buf + len, PAGE_SIZE - len,
"\n");
if (len >= PAGE_SIZE)
return -EFBIG;
}
break;
default:
for (i = 0; i < length / 2; i++) {
len += __iio_format_value(buf + len, PAGE_SIZE - len,
type, 2, &vals[i * 2]);
if (len >= PAGE_SIZE)
return -EFBIG;
if (i < length / 2 - 1)
len += snprintf(buf + len, PAGE_SIZE - len,
" ");
else
len += snprintf(buf + len, PAGE_SIZE - len,
"\n");
if (len >= PAGE_SIZE)
return -EFBIG;
}
}
return len;
}
static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
{
int i;
ssize_t len;
len = snprintf(buf, PAGE_SIZE, "[");
switch (type) {
case IIO_VAL_INT:
for (i = 0; i < 3; i++) {
len += __iio_format_value(buf + len, PAGE_SIZE - len,
type, 1, &vals[i]);
if (len >= PAGE_SIZE)
return -EFBIG;
if (i < 2)
len += snprintf(buf + len, PAGE_SIZE - len,
" ");
else
len += snprintf(buf + len, PAGE_SIZE - len,
"]\n");
if (len >= PAGE_SIZE)
return -EFBIG;
}
break;
default:
for (i = 0; i < 3; i++) {
len += __iio_format_value(buf + len, PAGE_SIZE - len,
type, 2, &vals[i * 2]);
if (len >= PAGE_SIZE)
return -EFBIG;
if (i < 2)
len += snprintf(buf + len, PAGE_SIZE - len,
" ");
else
len += snprintf(buf + len, PAGE_SIZE - len,
"]\n");
if (len >= PAGE_SIZE)
return -EFBIG;
}
}
return len;
}
static ssize_t iio_read_channel_info_avail(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 int *vals;
int ret;
int length;
int type;
ret = indio_dev->info->read_avail(indio_dev, this_attr->c,
&vals, &type, &length,
this_attr->address);
if (ret < 0)
return ret;
switch (ret) {
case IIO_AVAIL_LIST:
return iio_format_avail_list(buf, vals, type, length);
case IIO_AVAIL_RANGE:
return iio_format_avail_range(buf, vals, type);
default:
return -EINVAL;
}
}
/**
* 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 (fract_mult == 0) {
*fract = 0;
return kstrtoint(str, 0, integer);
}
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:
fract_mult = 0;
break;
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(1, "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_info_mask_type_avail(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;
char *avail_postfix;
for_each_set_bit(i, infomask, sizeof(infomask) * 8) {
avail_postfix = kasprintf(GFP_KERNEL,
"%s_available",
iio_chan_info_postfix[i]);
if (!avail_postfix)
return -ENOMEM;
ret = __iio_add_chan_devattr(avail_postfix,
chan,
&iio_read_channel_info_avail,
NULL,
i,
shared_by,
&indio_dev->dev,
&indio_dev->channel_attr_list);
kfree(avail_postfix);
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_avail(indio_dev, chan,
IIO_SEPARATE,
&chan->
info_mask_separate_available);
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_avail(indio_dev, chan,
IIO_SHARED_BY_TYPE,
&chan->
info_mask_shared_by_type_available);
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_avail(indio_dev, chan,
IIO_SHARED_BY_DIR,
&chan->info_mask_shared_by_dir_available);
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;
ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
IIO_SHARED_BY_ALL,
&chan->info_mask_shared_by_all_available);
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.
*/
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);
list_del(&p->l);
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 ssize_t iio_show_timestamp_clock(struct device *dev,
struct device_attribute *attr,
char *buf)
{
const struct iio_dev *indio_dev = dev_to_iio_dev(dev);
const clockid_t clk = iio_device_get_clock(indio_dev);
const char *name;
ssize_t sz;
switch (clk) {
case CLOCK_REALTIME:
name = "realtime\n";
sz = sizeof("realtime\n");
break;
case CLOCK_MONOTONIC:
name = "monotonic\n";
sz = sizeof("monotonic\n");
break;
case CLOCK_MONOTONIC_RAW:
name = "monotonic_raw\n";
sz = sizeof("monotonic_raw\n");
break;
case CLOCK_REALTIME_COARSE:
name = "realtime_coarse\n";
sz = sizeof("realtime_coarse\n");
break;
case CLOCK_MONOTONIC_COARSE:
name = "monotonic_coarse\n";
sz = sizeof("monotonic_coarse\n");
break;
case CLOCK_BOOTTIME:
name = "boottime\n";
sz = sizeof("boottime\n");
break;
case CLOCK_TAI:
name = "tai\n";
sz = sizeof("tai\n");
break;
default:
BUG();
}
memcpy(buf, name, sz);
return sz;
}
static ssize_t iio_store_timestamp_clock(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
clockid_t clk;
int ret;
if (sysfs_streq(buf, "realtime"))
clk = CLOCK_REALTIME;
else if (sysfs_streq(buf, "monotonic"))
clk = CLOCK_MONOTONIC;
else if (sysfs_streq(buf, "monotonic_raw"))
clk = CLOCK_MONOTONIC_RAW;
else if (sysfs_streq(buf, "realtime_coarse"))
clk = CLOCK_REALTIME_COARSE;
else if (sysfs_streq(buf, "monotonic_coarse"))
clk = CLOCK_MONOTONIC_COARSE;
else if (sysfs_streq(buf, "boottime"))
clk = CLOCK_BOOTTIME;
else if (sysfs_streq(buf, "tai"))
clk = CLOCK_TAI;
else
return -EINVAL;
ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);
if (ret)
return ret;
return len;
}
static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
iio_show_timestamp_clock, iio_store_timestamp_clock);
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, *clk = NULL;
/* 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++) {
const struct iio_chan_spec *chan =
&indio_dev->channels[i];
if (chan->type == IIO_TIMESTAMP)
clk = &dev_attr_current_timestamp_clock.attr;
ret = iio_device_add_channel_sysfs(indio_dev, chan);
if (ret < 0)
goto error_clear_attrs;
attrcount += ret;
}
if (indio_dev->event_interface)
clk = &dev_attr_current_timestamp_clock.attr;
if (indio_dev->name)
attrcount++;
if (clk)
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;
if (clk)
indio_dev->chan_attr_group.attrs[attrn++] = clk;
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);
indio_dev->chan_attr_group.attrs = NULL;
}
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 | INDIO_EVENT_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);
}
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;
}
EXPORT_SYMBOL_GPL(devm_iio_device_match);
/**
* 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;
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
* @inode: Inode structure for identifying the device in the file system
* @filp: File structure for iio device used to keep and later access
* private data
*
* Return: 0 on success or -EBUSY if the device is already opened
**/
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
* @inode: Inode structure pointer for the char device
* @filp: File structure pointer for the char device
*
* Return: 0 for successful release
*/
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 (fd < 0)
return fd;
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 int iio_check_unique_scan_index(struct iio_dev *indio_dev)
{
int i, j;
const struct iio_chan_spec *channels = indio_dev->channels;
if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
return 0;
for (i = 0; i < indio_dev->num_channels - 1; i++) {
if (channels[i].scan_index < 0)
continue;
for (j = i + 1; j < indio_dev->num_channels; j++)
if (channels[i].scan_index == channels[j].scan_index) {
dev_err(&indio_dev->dev,
"Duplicate scan index %d\n",
channels[i].scan_index);
return -EINVAL;
}
}
return 0;
}
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;
ret = iio_check_unique_scan_index(indio_dev);
if (ret < 0)
return 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");
return ret;
}
ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
if (ret) {
dev_err(indio_dev->dev.parent,
"Failed to create buffer sysfs interfaces\n");
goto error_unreg_debugfs;
}
ret = iio_device_register_sysfs(indio_dev);
if (ret) {
dev_err(indio_dev->dev.parent,
"Failed to register sysfs interfaces\n");
goto error_buffer_free_sysfs;
}
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 | INDIO_EVENT_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_buffer_free_sysfs:
iio_buffer_free_sysfs_and_mask(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);
iio_buffer_free_sysfs_and_mask(indio_dev);
}
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);
/**
* iio_device_claim_direct_mode - Keep device in direct mode
* @indio_dev: the iio_dev associated with the device
*
* If the device is in direct mode it is guaranteed to stay
* that way until iio_device_release_direct_mode() is called.
*
* Use with iio_device_release_direct_mode()
*
* Returns: 0 on success, -EBUSY on failure
*/
int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
{
mutex_lock(&indio_dev->mlock);
if (iio_buffer_enabled(indio_dev)) {
mutex_unlock(&indio_dev->mlock);
return -EBUSY;
}
return 0;
}
EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
/**
* iio_device_release_direct_mode - releases claim on direct mode
* @indio_dev: the iio_dev associated with the device
*
* Release the claim. Device is no longer guaranteed to stay
* in direct mode.
*
* Use with iio_device_claim_direct_mode()
*/
void iio_device_release_direct_mode(struct iio_dev *indio_dev)
{
mutex_unlock(&indio_dev->mlock);
}
EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
subsys_initcall(iio_init);
module_exit(iio_exit);
MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
MODULE_DESCRIPTION("Industrial I/O core");
MODULE_LICENSE("GPL");