1 /* The industrial I/O core
3 * Copyright (c) 2008 Jonathan Cameron
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
9 * Based on elements of hwmon and input subsystems.
12 #define pr_fmt(fmt) "iio-core: " fmt
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/idr.h>
17 #include <linux/kdev_t.h>
18 #include <linux/err.h>
19 #include <linux/device.h>
21 #include <linux/poll.h>
22 #include <linux/sched.h>
23 #include <linux/wait.h>
24 #include <linux/cdev.h>
25 #include <linux/slab.h>
26 #include <linux/anon_inodes.h>
27 #include <linux/debugfs.h>
28 #include <linux/mutex.h>
29 #include <linux/iio/iio.h>
31 #include "iio_core_trigger.h"
32 #include <linux/iio/sysfs.h>
33 #include <linux/iio/events.h>
34 #include <linux/iio/buffer.h>
35 #include <linux/iio/buffer_impl.h>
37 /* IDA to assign each registered device a unique id */
38 static DEFINE_IDA(iio_ida);
40 static dev_t iio_devt;
42 #define IIO_DEV_MAX 256
43 struct bus_type iio_bus_type = {
46 EXPORT_SYMBOL(iio_bus_type);
48 static struct dentry *iio_debugfs_dentry;
50 static const char * const iio_direction[] = {
55 static const char * const iio_chan_type_name_spec[] = {
56 [IIO_VOLTAGE] = "voltage",
57 [IIO_CURRENT] = "current",
58 [IIO_POWER] = "power",
59 [IIO_ACCEL] = "accel",
60 [IIO_ANGL_VEL] = "anglvel",
62 [IIO_LIGHT] = "illuminance",
63 [IIO_INTENSITY] = "intensity",
64 [IIO_PROXIMITY] = "proximity",
66 [IIO_INCLI] = "incli",
69 [IIO_TIMESTAMP] = "timestamp",
70 [IIO_CAPACITANCE] = "capacitance",
71 [IIO_ALTVOLTAGE] = "altvoltage",
73 [IIO_PRESSURE] = "pressure",
74 [IIO_HUMIDITYRELATIVE] = "humidityrelative",
75 [IIO_ACTIVITY] = "activity",
76 [IIO_STEPS] = "steps",
77 [IIO_ENERGY] = "energy",
78 [IIO_DISTANCE] = "distance",
79 [IIO_VELOCITY] = "velocity",
80 [IIO_CONCENTRATION] = "concentration",
81 [IIO_RESISTANCE] = "resistance",
83 [IIO_UVINDEX] = "uvindex",
84 [IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",
85 [IIO_COUNT] = "count",
86 [IIO_INDEX] = "index",
87 [IIO_GRAVITY] = "gravity",
90 static const char * const iio_modifier_names[] = {
94 [IIO_MOD_X_AND_Y] = "x&y",
95 [IIO_MOD_X_AND_Z] = "x&z",
96 [IIO_MOD_Y_AND_Z] = "y&z",
97 [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
98 [IIO_MOD_X_OR_Y] = "x|y",
99 [IIO_MOD_X_OR_Z] = "x|z",
100 [IIO_MOD_Y_OR_Z] = "y|z",
101 [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
102 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
103 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
104 [IIO_MOD_LIGHT_BOTH] = "both",
105 [IIO_MOD_LIGHT_IR] = "ir",
106 [IIO_MOD_LIGHT_CLEAR] = "clear",
107 [IIO_MOD_LIGHT_RED] = "red",
108 [IIO_MOD_LIGHT_GREEN] = "green",
109 [IIO_MOD_LIGHT_BLUE] = "blue",
110 [IIO_MOD_LIGHT_UV] = "uv",
111 [IIO_MOD_QUATERNION] = "quaternion",
112 [IIO_MOD_TEMP_AMBIENT] = "ambient",
113 [IIO_MOD_TEMP_OBJECT] = "object",
114 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
115 [IIO_MOD_NORTH_TRUE] = "from_north_true",
116 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
117 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
118 [IIO_MOD_RUNNING] = "running",
119 [IIO_MOD_JOGGING] = "jogging",
120 [IIO_MOD_WALKING] = "walking",
121 [IIO_MOD_STILL] = "still",
122 [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
125 [IIO_MOD_CO2] = "co2",
126 [IIO_MOD_VOC] = "voc",
129 /* relies on pairs of these shared then separate */
130 static const char * const iio_chan_info_postfix[] = {
131 [IIO_CHAN_INFO_RAW] = "raw",
132 [IIO_CHAN_INFO_PROCESSED] = "input",
133 [IIO_CHAN_INFO_SCALE] = "scale",
134 [IIO_CHAN_INFO_OFFSET] = "offset",
135 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
136 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
137 [IIO_CHAN_INFO_PEAK] = "peak_raw",
138 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
139 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
140 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
141 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
142 = "filter_low_pass_3db_frequency",
143 [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
144 = "filter_high_pass_3db_frequency",
145 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
146 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
147 [IIO_CHAN_INFO_PHASE] = "phase",
148 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
149 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
150 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
151 [IIO_CHAN_INFO_ENABLE] = "en",
152 [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
153 [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
154 [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
155 [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
156 [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
157 [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
161 * iio_find_channel_from_si() - get channel from its scan index
163 * @si: scan index to match
165 const struct iio_chan_spec
166 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
170 for (i = 0; i < indio_dev->num_channels; i++)
171 if (indio_dev->channels[i].scan_index == si)
172 return &indio_dev->channels[i];
176 /* This turns up an awful lot */
177 ssize_t iio_read_const_attr(struct device *dev,
178 struct device_attribute *attr,
181 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
183 EXPORT_SYMBOL(iio_read_const_attr);
185 static int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id)
188 const struct iio_event_interface *ev_int = indio_dev->event_interface;
190 ret = mutex_lock_interruptible(&indio_dev->mlock);
193 if ((ev_int && iio_event_enabled(ev_int)) ||
194 iio_buffer_enabled(indio_dev)) {
195 mutex_unlock(&indio_dev->mlock);
198 indio_dev->clock_id = clock_id;
199 mutex_unlock(&indio_dev->mlock);
205 * iio_get_time_ns() - utility function to get a time stamp for events etc
208 s64 iio_get_time_ns(const struct iio_dev *indio_dev)
212 switch (iio_device_get_clock(indio_dev)) {
214 ktime_get_real_ts(&tp);
216 case CLOCK_MONOTONIC:
219 case CLOCK_MONOTONIC_RAW:
220 getrawmonotonic(&tp);
222 case CLOCK_REALTIME_COARSE:
223 tp = current_kernel_time();
225 case CLOCK_MONOTONIC_COARSE:
226 tp = get_monotonic_coarse();
229 get_monotonic_boottime(&tp);
232 timekeeping_clocktai(&tp);
238 return timespec_to_ns(&tp);
240 EXPORT_SYMBOL(iio_get_time_ns);
243 * iio_get_time_res() - utility function to get time stamp clock resolution in
247 unsigned int iio_get_time_res(const struct iio_dev *indio_dev)
249 switch (iio_device_get_clock(indio_dev)) {
251 case CLOCK_MONOTONIC:
252 case CLOCK_MONOTONIC_RAW:
255 return hrtimer_resolution;
256 case CLOCK_REALTIME_COARSE:
257 case CLOCK_MONOTONIC_COARSE:
263 EXPORT_SYMBOL(iio_get_time_res);
265 static int __init iio_init(void)
269 /* Register sysfs bus */
270 ret = bus_register(&iio_bus_type);
272 pr_err("could not register bus type\n");
276 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
278 pr_err("failed to allocate char dev region\n");
279 goto error_unregister_bus_type;
282 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
286 error_unregister_bus_type:
287 bus_unregister(&iio_bus_type);
292 static void __exit iio_exit(void)
295 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
296 bus_unregister(&iio_bus_type);
297 debugfs_remove(iio_debugfs_dentry);
300 #if defined(CONFIG_DEBUG_FS)
301 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
302 size_t count, loff_t *ppos)
304 struct iio_dev *indio_dev = file->private_data;
310 ret = indio_dev->info->debugfs_reg_access(indio_dev,
311 indio_dev->cached_reg_addr,
314 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
318 len = snprintf(buf, sizeof(buf), "0x%X\n", val);
320 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
323 static ssize_t iio_debugfs_write_reg(struct file *file,
324 const char __user *userbuf, size_t count, loff_t *ppos)
326 struct iio_dev *indio_dev = file->private_data;
331 count = min_t(size_t, count, (sizeof(buf)-1));
332 if (copy_from_user(buf, userbuf, count))
337 ret = sscanf(buf, "%i %i", ®, &val);
341 indio_dev->cached_reg_addr = reg;
344 indio_dev->cached_reg_addr = reg;
345 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
348 dev_err(indio_dev->dev.parent, "%s: write failed\n",
360 static const struct file_operations iio_debugfs_reg_fops = {
362 .read = iio_debugfs_read_reg,
363 .write = iio_debugfs_write_reg,
366 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
368 debugfs_remove_recursive(indio_dev->debugfs_dentry);
371 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
375 if (indio_dev->info->debugfs_reg_access == NULL)
378 if (!iio_debugfs_dentry)
381 indio_dev->debugfs_dentry =
382 debugfs_create_dir(dev_name(&indio_dev->dev),
384 if (indio_dev->debugfs_dentry == NULL) {
385 dev_warn(indio_dev->dev.parent,
386 "Failed to create debugfs directory\n");
390 d = debugfs_create_file("direct_reg_access", 0644,
391 indio_dev->debugfs_dentry,
392 indio_dev, &iio_debugfs_reg_fops);
394 iio_device_unregister_debugfs(indio_dev);
401 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
406 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
409 #endif /* CONFIG_DEBUG_FS */
411 static ssize_t iio_read_channel_ext_info(struct device *dev,
412 struct device_attribute *attr,
415 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
416 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
417 const struct iio_chan_spec_ext_info *ext_info;
419 ext_info = &this_attr->c->ext_info[this_attr->address];
421 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
424 static ssize_t iio_write_channel_ext_info(struct device *dev,
425 struct device_attribute *attr,
429 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
430 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
431 const struct iio_chan_spec_ext_info *ext_info;
433 ext_info = &this_attr->c->ext_info[this_attr->address];
435 return ext_info->write(indio_dev, ext_info->private,
436 this_attr->c, buf, len);
439 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
440 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
442 const struct iio_enum *e = (const struct iio_enum *)priv;
449 for (i = 0; i < e->num_items; ++i)
450 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
452 /* replace last space with a newline */
457 EXPORT_SYMBOL_GPL(iio_enum_available_read);
459 ssize_t iio_enum_read(struct iio_dev *indio_dev,
460 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
462 const struct iio_enum *e = (const struct iio_enum *)priv;
468 i = e->get(indio_dev, chan);
471 else if (i >= e->num_items)
474 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
476 EXPORT_SYMBOL_GPL(iio_enum_read);
478 ssize_t iio_enum_write(struct iio_dev *indio_dev,
479 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
482 const struct iio_enum *e = (const struct iio_enum *)priv;
488 ret = __sysfs_match_string(e->items, e->num_items, buf);
492 ret = e->set(indio_dev, chan, ret);
493 return ret ? ret : len;
495 EXPORT_SYMBOL_GPL(iio_enum_write);
497 static const struct iio_mount_matrix iio_mount_idmatrix = {
505 static int iio_setup_mount_idmatrix(const struct device *dev,
506 struct iio_mount_matrix *matrix)
508 *matrix = iio_mount_idmatrix;
509 dev_info(dev, "mounting matrix not found: using identity...\n");
513 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
514 const struct iio_chan_spec *chan, char *buf)
516 const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
517 priv)(indio_dev, chan);
523 mtx = &iio_mount_idmatrix;
525 return snprintf(buf, PAGE_SIZE, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
526 mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
527 mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
528 mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
530 EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
533 * of_iio_read_mount_matrix() - retrieve iio device mounting matrix from
534 * device-tree "mount-matrix" property
535 * @dev: device the mounting matrix property is assigned to
536 * @propname: device specific mounting matrix property name
537 * @matrix: where to store retrieved matrix
539 * If device is assigned no mounting matrix property, a default 3x3 identity
540 * matrix will be filled in.
542 * Return: 0 if success, or a negative error code on failure.
545 int of_iio_read_mount_matrix(const struct device *dev,
546 const char *propname,
547 struct iio_mount_matrix *matrix)
550 int err = of_property_read_string_array(dev->of_node,
551 propname, matrix->rotation,
552 ARRAY_SIZE(iio_mount_idmatrix.rotation));
554 if (err == ARRAY_SIZE(iio_mount_idmatrix.rotation))
558 /* Invalid number of matrix entries. */
562 /* Invalid matrix declaration format. */
566 /* Matrix was not declared at all: fallback to identity. */
567 return iio_setup_mount_idmatrix(dev, matrix);
570 int of_iio_read_mount_matrix(const struct device *dev,
571 const char *propname,
572 struct iio_mount_matrix *matrix)
574 return iio_setup_mount_idmatrix(dev, matrix);
577 EXPORT_SYMBOL(of_iio_read_mount_matrix);
579 static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
580 int size, const int *vals)
582 unsigned long long tmp;
584 bool scale_db = false;
588 return snprintf(buf, len, "%d", vals[0]);
589 case IIO_VAL_INT_PLUS_MICRO_DB:
591 case IIO_VAL_INT_PLUS_MICRO:
593 return snprintf(buf, len, "-%d.%06u%s", abs(vals[0]),
594 -vals[1], scale_db ? " dB" : "");
596 return snprintf(buf, len, "%d.%06u%s", vals[0], vals[1],
597 scale_db ? " dB" : "");
598 case IIO_VAL_INT_PLUS_NANO:
600 return snprintf(buf, len, "-%d.%09u", abs(vals[0]),
603 return snprintf(buf, len, "%d.%09u", vals[0], vals[1]);
604 case IIO_VAL_FRACTIONAL:
605 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
607 tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
608 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
609 case IIO_VAL_FRACTIONAL_LOG2:
610 tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
611 tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
612 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
613 case IIO_VAL_INT_MULTIPLE:
618 for (i = 0; i < size; ++i) {
619 l += snprintf(&buf[l], len - l, "%d ", vals[i]);
631 * iio_format_value() - Formats a IIO value into its string representation
632 * @buf: The buffer to which the formatted value gets written
633 * which is assumed to be big enough (i.e. PAGE_SIZE).
634 * @type: One of the IIO_VAL_* constants. This decides how the val
635 * and val2 parameters are formatted.
636 * @size: Number of IIO value entries contained in vals
637 * @vals: Pointer to the values, exact meaning depends on the
640 * Return: 0 by default, a negative number on failure or the
641 * total number of characters written for a type that belongs
642 * to the IIO_VAL_* constant.
644 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
648 len = __iio_format_value(buf, PAGE_SIZE, type, size, vals);
649 if (len >= PAGE_SIZE - 1)
652 return len + sprintf(buf + len, "\n");
654 EXPORT_SYMBOL_GPL(iio_format_value);
656 static ssize_t iio_read_channel_info(struct device *dev,
657 struct device_attribute *attr,
660 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
661 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
662 int vals[INDIO_MAX_RAW_ELEMENTS];
666 if (indio_dev->info->read_raw_multi)
667 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
668 INDIO_MAX_RAW_ELEMENTS,
672 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
673 &vals[0], &vals[1], this_attr->address);
678 return iio_format_value(buf, ret, val_len, vals);
681 static ssize_t iio_format_avail_list(char *buf, const int *vals,
682 int type, int length)
689 for (i = 0; i < length; i++) {
690 len += __iio_format_value(buf + len, PAGE_SIZE - len,
692 if (len >= PAGE_SIZE)
695 len += snprintf(buf + len, PAGE_SIZE - len,
698 len += snprintf(buf + len, PAGE_SIZE - len,
700 if (len >= PAGE_SIZE)
705 for (i = 0; i < length / 2; i++) {
706 len += __iio_format_value(buf + len, PAGE_SIZE - len,
707 type, 2, &vals[i * 2]);
708 if (len >= PAGE_SIZE)
710 if (i < length / 2 - 1)
711 len += snprintf(buf + len, PAGE_SIZE - len,
714 len += snprintf(buf + len, PAGE_SIZE - len,
716 if (len >= PAGE_SIZE)
724 static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
729 len = snprintf(buf, PAGE_SIZE, "[");
732 for (i = 0; i < 3; i++) {
733 len += __iio_format_value(buf + len, PAGE_SIZE - len,
735 if (len >= PAGE_SIZE)
738 len += snprintf(buf + len, PAGE_SIZE - len,
741 len += snprintf(buf + len, PAGE_SIZE - len,
743 if (len >= PAGE_SIZE)
748 for (i = 0; i < 3; i++) {
749 len += __iio_format_value(buf + len, PAGE_SIZE - len,
750 type, 2, &vals[i * 2]);
751 if (len >= PAGE_SIZE)
754 len += snprintf(buf + len, PAGE_SIZE - len,
757 len += snprintf(buf + len, PAGE_SIZE - len,
759 if (len >= PAGE_SIZE)
767 static ssize_t iio_read_channel_info_avail(struct device *dev,
768 struct device_attribute *attr,
771 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
772 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
778 ret = indio_dev->info->read_avail(indio_dev, this_attr->c,
779 &vals, &type, &length,
786 return iio_format_avail_list(buf, vals, type, length);
787 case IIO_AVAIL_RANGE:
788 return iio_format_avail_range(buf, vals, type);
795 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
796 * @str: The string to parse
797 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
798 * @integer: The integer part of the number
799 * @fract: The fractional part of the number
801 * Returns 0 on success, or a negative error code if the string could not be
804 int iio_str_to_fixpoint(const char *str, int fract_mult,
805 int *integer, int *fract)
808 bool integer_part = true, negative = false;
810 if (fract_mult == 0) {
813 return kstrtoint(str, 0, integer);
819 } else if (str[0] == '+') {
824 if ('0' <= *str && *str <= '9') {
826 i = i * 10 + *str - '0';
828 f += fract_mult * (*str - '0');
831 } else if (*str == '\n') {
832 if (*(str + 1) == '\0')
836 } else if (*str == '.' && integer_part) {
837 integer_part = false;
856 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
858 static ssize_t iio_write_channel_info(struct device *dev,
859 struct device_attribute *attr,
863 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
864 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
865 int ret, fract_mult = 100000;
868 /* Assumes decimal - precision based on number of digits */
869 if (!indio_dev->info->write_raw)
872 if (indio_dev->info->write_raw_get_fmt)
873 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
874 this_attr->c, this_attr->address)) {
878 case IIO_VAL_INT_PLUS_MICRO:
881 case IIO_VAL_INT_PLUS_NANO:
882 fract_mult = 100000000;
888 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
892 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
893 integer, fract, this_attr->address);
901 int __iio_device_attr_init(struct device_attribute *dev_attr,
903 struct iio_chan_spec const *chan,
904 ssize_t (*readfunc)(struct device *dev,
905 struct device_attribute *attr,
907 ssize_t (*writefunc)(struct device *dev,
908 struct device_attribute *attr,
911 enum iio_shared_by shared_by)
916 sysfs_attr_init(&dev_attr->attr);
918 /* Build up postfix of <extend_name>_<modifier>_postfix */
919 if (chan->modified && (shared_by == IIO_SEPARATE)) {
920 if (chan->extend_name)
921 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
922 iio_modifier_names[chan
927 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
928 iio_modifier_names[chan
932 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
933 full_postfix = kstrdup(postfix, GFP_KERNEL);
935 full_postfix = kasprintf(GFP_KERNEL,
940 if (full_postfix == NULL)
943 if (chan->differential) { /* Differential can not have modifier */
945 case IIO_SHARED_BY_ALL:
946 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
948 case IIO_SHARED_BY_DIR:
949 name = kasprintf(GFP_KERNEL, "%s_%s",
950 iio_direction[chan->output],
953 case IIO_SHARED_BY_TYPE:
954 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
955 iio_direction[chan->output],
956 iio_chan_type_name_spec[chan->type],
957 iio_chan_type_name_spec[chan->type],
961 if (!chan->indexed) {
962 WARN(1, "Differential channels must be indexed\n");
964 goto error_free_full_postfix;
966 name = kasprintf(GFP_KERNEL,
968 iio_direction[chan->output],
969 iio_chan_type_name_spec[chan->type],
971 iio_chan_type_name_spec[chan->type],
976 } else { /* Single ended */
978 case IIO_SHARED_BY_ALL:
979 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
981 case IIO_SHARED_BY_DIR:
982 name = kasprintf(GFP_KERNEL, "%s_%s",
983 iio_direction[chan->output],
986 case IIO_SHARED_BY_TYPE:
987 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
988 iio_direction[chan->output],
989 iio_chan_type_name_spec[chan->type],
995 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
996 iio_direction[chan->output],
997 iio_chan_type_name_spec[chan->type],
1001 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
1002 iio_direction[chan->output],
1003 iio_chan_type_name_spec[chan->type],
1010 goto error_free_full_postfix;
1012 dev_attr->attr.name = name;
1015 dev_attr->attr.mode |= S_IRUGO;
1016 dev_attr->show = readfunc;
1020 dev_attr->attr.mode |= S_IWUSR;
1021 dev_attr->store = writefunc;
1024 error_free_full_postfix:
1025 kfree(full_postfix);
1030 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
1032 kfree(dev_attr->attr.name);
1035 int __iio_add_chan_devattr(const char *postfix,
1036 struct iio_chan_spec const *chan,
1037 ssize_t (*readfunc)(struct device *dev,
1038 struct device_attribute *attr,
1040 ssize_t (*writefunc)(struct device *dev,
1041 struct device_attribute *attr,
1045 enum iio_shared_by shared_by,
1047 struct list_head *attr_list)
1050 struct iio_dev_attr *iio_attr, *t;
1052 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
1053 if (iio_attr == NULL)
1055 ret = __iio_device_attr_init(&iio_attr->dev_attr,
1057 readfunc, writefunc, shared_by);
1059 goto error_iio_dev_attr_free;
1061 iio_attr->address = mask;
1062 list_for_each_entry(t, attr_list, l)
1063 if (strcmp(t->dev_attr.attr.name,
1064 iio_attr->dev_attr.attr.name) == 0) {
1065 if (shared_by == IIO_SEPARATE)
1066 dev_err(dev, "tried to double register : %s\n",
1067 t->dev_attr.attr.name);
1069 goto error_device_attr_deinit;
1071 list_add(&iio_attr->l, attr_list);
1075 error_device_attr_deinit:
1076 __iio_device_attr_deinit(&iio_attr->dev_attr);
1077 error_iio_dev_attr_free:
1082 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
1083 struct iio_chan_spec const *chan,
1084 enum iio_shared_by shared_by,
1085 const long *infomask)
1087 int i, ret, attrcount = 0;
1089 for_each_set_bit(i, infomask, sizeof(*infomask)*8) {
1090 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1092 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
1094 &iio_read_channel_info,
1095 &iio_write_channel_info,
1099 &indio_dev->channel_attr_list);
1100 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1110 static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
1111 struct iio_chan_spec const *chan,
1112 enum iio_shared_by shared_by,
1113 const long *infomask)
1115 int i, ret, attrcount = 0;
1116 char *avail_postfix;
1118 for_each_set_bit(i, infomask, sizeof(*infomask) * 8) {
1119 avail_postfix = kasprintf(GFP_KERNEL,
1121 iio_chan_info_postfix[i]);
1125 ret = __iio_add_chan_devattr(avail_postfix,
1127 &iio_read_channel_info_avail,
1132 &indio_dev->channel_attr_list);
1133 kfree(avail_postfix);
1134 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1144 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
1145 struct iio_chan_spec const *chan)
1147 int ret, attrcount = 0;
1148 const struct iio_chan_spec_ext_info *ext_info;
1150 if (chan->channel < 0)
1152 ret = iio_device_add_info_mask_type(indio_dev, chan,
1154 &chan->info_mask_separate);
1159 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1162 info_mask_separate_available);
1167 ret = iio_device_add_info_mask_type(indio_dev, chan,
1169 &chan->info_mask_shared_by_type);
1174 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1177 info_mask_shared_by_type_available);
1182 ret = iio_device_add_info_mask_type(indio_dev, chan,
1184 &chan->info_mask_shared_by_dir);
1189 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1191 &chan->info_mask_shared_by_dir_available);
1196 ret = iio_device_add_info_mask_type(indio_dev, chan,
1198 &chan->info_mask_shared_by_all);
1203 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1205 &chan->info_mask_shared_by_all_available);
1210 if (chan->ext_info) {
1212 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
1213 ret = __iio_add_chan_devattr(ext_info->name,
1216 &iio_read_channel_ext_info : NULL,
1218 &iio_write_channel_ext_info : NULL,
1222 &indio_dev->channel_attr_list);
1224 if (ret == -EBUSY && ext_info->shared)
1238 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
1239 * @attr_list: List of IIO device attributes
1241 * This function frees the memory allocated for each of the IIO device
1242 * attributes in the list.
1244 void iio_free_chan_devattr_list(struct list_head *attr_list)
1246 struct iio_dev_attr *p, *n;
1248 list_for_each_entry_safe(p, n, attr_list, l) {
1249 kfree(p->dev_attr.attr.name);
1255 static ssize_t iio_show_dev_name(struct device *dev,
1256 struct device_attribute *attr,
1259 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1260 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
1263 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
1265 static ssize_t iio_show_timestamp_clock(struct device *dev,
1266 struct device_attribute *attr,
1269 const struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1270 const clockid_t clk = iio_device_get_clock(indio_dev);
1275 case CLOCK_REALTIME:
1276 name = "realtime\n";
1277 sz = sizeof("realtime\n");
1279 case CLOCK_MONOTONIC:
1280 name = "monotonic\n";
1281 sz = sizeof("monotonic\n");
1283 case CLOCK_MONOTONIC_RAW:
1284 name = "monotonic_raw\n";
1285 sz = sizeof("monotonic_raw\n");
1287 case CLOCK_REALTIME_COARSE:
1288 name = "realtime_coarse\n";
1289 sz = sizeof("realtime_coarse\n");
1291 case CLOCK_MONOTONIC_COARSE:
1292 name = "monotonic_coarse\n";
1293 sz = sizeof("monotonic_coarse\n");
1295 case CLOCK_BOOTTIME:
1296 name = "boottime\n";
1297 sz = sizeof("boottime\n");
1301 sz = sizeof("tai\n");
1307 memcpy(buf, name, sz);
1311 static ssize_t iio_store_timestamp_clock(struct device *dev,
1312 struct device_attribute *attr,
1313 const char *buf, size_t len)
1318 if (sysfs_streq(buf, "realtime"))
1319 clk = CLOCK_REALTIME;
1320 else if (sysfs_streq(buf, "monotonic"))
1321 clk = CLOCK_MONOTONIC;
1322 else if (sysfs_streq(buf, "monotonic_raw"))
1323 clk = CLOCK_MONOTONIC_RAW;
1324 else if (sysfs_streq(buf, "realtime_coarse"))
1325 clk = CLOCK_REALTIME_COARSE;
1326 else if (sysfs_streq(buf, "monotonic_coarse"))
1327 clk = CLOCK_MONOTONIC_COARSE;
1328 else if (sysfs_streq(buf, "boottime"))
1329 clk = CLOCK_BOOTTIME;
1330 else if (sysfs_streq(buf, "tai"))
1335 ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);
1342 static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
1343 iio_show_timestamp_clock, iio_store_timestamp_clock);
1345 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
1347 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
1348 struct iio_dev_attr *p;
1349 struct attribute **attr, *clk = NULL;
1351 /* First count elements in any existing group */
1352 if (indio_dev->info->attrs) {
1353 attr = indio_dev->info->attrs->attrs;
1354 while (*attr++ != NULL)
1357 attrcount = attrcount_orig;
1359 * New channel registration method - relies on the fact a group does
1360 * not need to be initialized if its name is NULL.
1362 if (indio_dev->channels)
1363 for (i = 0; i < indio_dev->num_channels; i++) {
1364 const struct iio_chan_spec *chan =
1365 &indio_dev->channels[i];
1367 if (chan->type == IIO_TIMESTAMP)
1368 clk = &dev_attr_current_timestamp_clock.attr;
1370 ret = iio_device_add_channel_sysfs(indio_dev, chan);
1372 goto error_clear_attrs;
1376 if (indio_dev->event_interface)
1377 clk = &dev_attr_current_timestamp_clock.attr;
1379 if (indio_dev->name)
1384 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
1385 sizeof(indio_dev->chan_attr_group.attrs[0]),
1387 if (indio_dev->chan_attr_group.attrs == NULL) {
1389 goto error_clear_attrs;
1391 /* Copy across original attributes */
1392 if (indio_dev->info->attrs)
1393 memcpy(indio_dev->chan_attr_group.attrs,
1394 indio_dev->info->attrs->attrs,
1395 sizeof(indio_dev->chan_attr_group.attrs[0])
1397 attrn = attrcount_orig;
1398 /* Add all elements from the list. */
1399 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
1400 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
1401 if (indio_dev->name)
1402 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
1404 indio_dev->chan_attr_group.attrs[attrn++] = clk;
1406 indio_dev->groups[indio_dev->groupcounter++] =
1407 &indio_dev->chan_attr_group;
1412 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1417 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
1420 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1421 kfree(indio_dev->chan_attr_group.attrs);
1422 indio_dev->chan_attr_group.attrs = NULL;
1425 static void iio_dev_release(struct device *device)
1427 struct iio_dev *indio_dev = dev_to_iio_dev(device);
1428 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1429 iio_device_unregister_trigger_consumer(indio_dev);
1430 iio_device_unregister_eventset(indio_dev);
1431 iio_device_unregister_sysfs(indio_dev);
1433 iio_buffer_put(indio_dev->buffer);
1435 ida_simple_remove(&iio_ida, indio_dev->id);
1439 struct device_type iio_device_type = {
1440 .name = "iio_device",
1441 .release = iio_dev_release,
1445 * iio_device_alloc() - allocate an iio_dev from a driver
1446 * @sizeof_priv: Space to allocate for private structure.
1448 struct iio_dev *iio_device_alloc(int sizeof_priv)
1450 struct iio_dev *dev;
1453 alloc_size = sizeof(struct iio_dev);
1455 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1456 alloc_size += sizeof_priv;
1458 /* ensure 32-byte alignment of whole construct ? */
1459 alloc_size += IIO_ALIGN - 1;
1461 dev = kzalloc(alloc_size, GFP_KERNEL);
1464 dev->dev.groups = dev->groups;
1465 dev->dev.type = &iio_device_type;
1466 dev->dev.bus = &iio_bus_type;
1467 device_initialize(&dev->dev);
1468 dev_set_drvdata(&dev->dev, (void *)dev);
1469 mutex_init(&dev->mlock);
1470 mutex_init(&dev->info_exist_lock);
1471 INIT_LIST_HEAD(&dev->channel_attr_list);
1473 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1475 /* cannot use a dev_err as the name isn't available */
1476 pr_err("failed to get device id\n");
1480 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1481 INIT_LIST_HEAD(&dev->buffer_list);
1486 EXPORT_SYMBOL(iio_device_alloc);
1489 * iio_device_free() - free an iio_dev from a driver
1490 * @dev: the iio_dev associated with the device
1492 void iio_device_free(struct iio_dev *dev)
1495 put_device(&dev->dev);
1497 EXPORT_SYMBOL(iio_device_free);
1499 static void devm_iio_device_release(struct device *dev, void *res)
1501 iio_device_free(*(struct iio_dev **)res);
1504 int devm_iio_device_match(struct device *dev, void *res, void *data)
1506 struct iio_dev **r = res;
1513 EXPORT_SYMBOL_GPL(devm_iio_device_match);
1516 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1517 * @dev: Device to allocate iio_dev for
1518 * @sizeof_priv: Space to allocate for private structure.
1520 * Managed iio_device_alloc. iio_dev allocated with this function is
1521 * automatically freed on driver detach.
1523 * If an iio_dev allocated with this function needs to be freed separately,
1524 * devm_iio_device_free() must be used.
1527 * Pointer to allocated iio_dev on success, NULL on failure.
1529 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1531 struct iio_dev **ptr, *iio_dev;
1533 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1538 iio_dev = iio_device_alloc(sizeof_priv);
1541 devres_add(dev, ptr);
1548 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1551 * devm_iio_device_free - Resource-managed iio_device_free()
1552 * @dev: Device this iio_dev belongs to
1553 * @iio_dev: the iio_dev associated with the device
1555 * Free iio_dev allocated with devm_iio_device_alloc().
1557 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1561 rc = devres_release(dev, devm_iio_device_release,
1562 devm_iio_device_match, iio_dev);
1565 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1568 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1569 * @inode: Inode structure for identifying the device in the file system
1570 * @filp: File structure for iio device used to keep and later access
1573 * Return: 0 on success or -EBUSY if the device is already opened
1575 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1577 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1578 struct iio_dev, chrdev);
1580 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1583 iio_device_get(indio_dev);
1585 filp->private_data = indio_dev;
1591 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1592 * @inode: Inode structure pointer for the char device
1593 * @filp: File structure pointer for the char device
1595 * Return: 0 for successful release
1597 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1599 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1600 struct iio_dev, chrdev);
1601 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1602 iio_device_put(indio_dev);
1607 /* Somewhat of a cross file organization violation - ioctls here are actually
1609 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1611 struct iio_dev *indio_dev = filp->private_data;
1612 int __user *ip = (int __user *)arg;
1615 if (!indio_dev->info)
1618 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1619 fd = iio_event_getfd(indio_dev);
1622 if (copy_to_user(ip, &fd, sizeof(fd)))
1629 static const struct file_operations iio_buffer_fileops = {
1630 .read = iio_buffer_read_first_n_outer_addr,
1631 .release = iio_chrdev_release,
1632 .open = iio_chrdev_open,
1633 .poll = iio_buffer_poll_addr,
1634 .owner = THIS_MODULE,
1635 .llseek = noop_llseek,
1636 .unlocked_ioctl = iio_ioctl,
1637 .compat_ioctl = iio_ioctl,
1640 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1643 const struct iio_chan_spec *channels = indio_dev->channels;
1645 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1648 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1649 if (channels[i].scan_index < 0)
1651 for (j = i + 1; j < indio_dev->num_channels; j++)
1652 if (channels[i].scan_index == channels[j].scan_index) {
1653 dev_err(&indio_dev->dev,
1654 "Duplicate scan index %d\n",
1655 channels[i].scan_index);
1663 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1666 * iio_device_register() - register a device with the IIO subsystem
1667 * @indio_dev: Device structure filled by the device driver
1669 int iio_device_register(struct iio_dev *indio_dev)
1673 /* If the calling driver did not initialize of_node, do it here */
1674 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1675 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1677 ret = iio_check_unique_scan_index(indio_dev);
1681 /* configure elements for the chrdev */
1682 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1684 ret = iio_device_register_debugfs(indio_dev);
1686 dev_err(indio_dev->dev.parent,
1687 "Failed to register debugfs interfaces\n");
1691 ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1693 dev_err(indio_dev->dev.parent,
1694 "Failed to create buffer sysfs interfaces\n");
1695 goto error_unreg_debugfs;
1698 ret = iio_device_register_sysfs(indio_dev);
1700 dev_err(indio_dev->dev.parent,
1701 "Failed to register sysfs interfaces\n");
1702 goto error_buffer_free_sysfs;
1704 ret = iio_device_register_eventset(indio_dev);
1706 dev_err(indio_dev->dev.parent,
1707 "Failed to register event set\n");
1708 goto error_free_sysfs;
1710 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1711 iio_device_register_trigger_consumer(indio_dev);
1713 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1714 indio_dev->setup_ops == NULL)
1715 indio_dev->setup_ops = &noop_ring_setup_ops;
1717 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1718 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1720 ret = cdev_device_add(&indio_dev->chrdev, &indio_dev->dev);
1722 goto error_unreg_eventset;
1726 error_unreg_eventset:
1727 iio_device_unregister_eventset(indio_dev);
1729 iio_device_unregister_sysfs(indio_dev);
1730 error_buffer_free_sysfs:
1731 iio_buffer_free_sysfs_and_mask(indio_dev);
1732 error_unreg_debugfs:
1733 iio_device_unregister_debugfs(indio_dev);
1736 EXPORT_SYMBOL(iio_device_register);
1739 * iio_device_unregister() - unregister a device from the IIO subsystem
1740 * @indio_dev: Device structure representing the device.
1742 void iio_device_unregister(struct iio_dev *indio_dev)
1744 cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
1746 mutex_lock(&indio_dev->info_exist_lock);
1748 iio_device_unregister_debugfs(indio_dev);
1750 iio_disable_all_buffers(indio_dev);
1752 indio_dev->info = NULL;
1754 iio_device_wakeup_eventset(indio_dev);
1755 iio_buffer_wakeup_poll(indio_dev);
1757 mutex_unlock(&indio_dev->info_exist_lock);
1759 iio_buffer_free_sysfs_and_mask(indio_dev);
1761 EXPORT_SYMBOL(iio_device_unregister);
1763 static void devm_iio_device_unreg(struct device *dev, void *res)
1765 iio_device_unregister(*(struct iio_dev **)res);
1769 * devm_iio_device_register - Resource-managed iio_device_register()
1770 * @dev: Device to allocate iio_dev for
1771 * @indio_dev: Device structure filled by the device driver
1773 * Managed iio_device_register. The IIO device registered with this
1774 * function is automatically unregistered on driver detach. This function
1775 * calls iio_device_register() internally. Refer to that function for more
1778 * If an iio_dev registered with this function needs to be unregistered
1779 * separately, devm_iio_device_unregister() must be used.
1782 * 0 on success, negative error number on failure.
1784 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev)
1786 struct iio_dev **ptr;
1789 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1794 ret = iio_device_register(indio_dev);
1796 devres_add(dev, ptr);
1802 EXPORT_SYMBOL_GPL(devm_iio_device_register);
1805 * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1806 * @dev: Device this iio_dev belongs to
1807 * @indio_dev: the iio_dev associated with the device
1809 * Unregister iio_dev registered with devm_iio_device_register().
1811 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1815 rc = devres_release(dev, devm_iio_device_unreg,
1816 devm_iio_device_match, indio_dev);
1819 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1822 * iio_device_claim_direct_mode - Keep device in direct mode
1823 * @indio_dev: the iio_dev associated with the device
1825 * If the device is in direct mode it is guaranteed to stay
1826 * that way until iio_device_release_direct_mode() is called.
1828 * Use with iio_device_release_direct_mode()
1830 * Returns: 0 on success, -EBUSY on failure
1832 int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
1834 mutex_lock(&indio_dev->mlock);
1836 if (iio_buffer_enabled(indio_dev)) {
1837 mutex_unlock(&indio_dev->mlock);
1842 EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
1845 * iio_device_release_direct_mode - releases claim on direct mode
1846 * @indio_dev: the iio_dev associated with the device
1848 * Release the claim. Device is no longer guaranteed to stay
1851 * Use with iio_device_claim_direct_mode()
1853 void iio_device_release_direct_mode(struct iio_dev *indio_dev)
1855 mutex_unlock(&indio_dev->mlock);
1857 EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
1859 subsys_initcall(iio_init);
1860 module_exit(iio_exit);
1862 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1863 MODULE_DESCRIPTION("Industrial I/O core");
1864 MODULE_LICENSE("GPL");