1 // SPDX-License-Identifier: GPL-2.0-only
2 /* The industrial I/O core
4 * Copyright (c) 2008 Jonathan Cameron
6 * Based on elements of hwmon and input subsystems.
9 #define pr_fmt(fmt) "iio-core: " fmt
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/idr.h>
14 #include <linux/kdev_t.h>
15 #include <linux/err.h>
16 #include <linux/device.h>
18 #include <linux/poll.h>
19 #include <linux/property.h>
20 #include <linux/sched.h>
21 #include <linux/wait.h>
22 #include <linux/cdev.h>
23 #include <linux/slab.h>
24 #include <linux/anon_inodes.h>
25 #include <linux/debugfs.h>
26 #include <linux/mutex.h>
27 #include <linux/iio/iio.h>
29 #include "iio_core_trigger.h"
30 #include <linux/iio/sysfs.h>
31 #include <linux/iio/events.h>
32 #include <linux/iio/buffer.h>
33 #include <linux/iio/buffer_impl.h>
35 /* IDA to assign each registered device a unique id */
36 static DEFINE_IDA(iio_ida);
38 static dev_t iio_devt;
40 #define IIO_DEV_MAX 256
41 struct bus_type iio_bus_type = {
44 EXPORT_SYMBOL(iio_bus_type);
46 static struct dentry *iio_debugfs_dentry;
48 static const char * const iio_direction[] = {
53 static const char * const iio_chan_type_name_spec[] = {
54 [IIO_VOLTAGE] = "voltage",
55 [IIO_CURRENT] = "current",
56 [IIO_POWER] = "power",
57 [IIO_ACCEL] = "accel",
58 [IIO_ANGL_VEL] = "anglvel",
60 [IIO_LIGHT] = "illuminance",
61 [IIO_INTENSITY] = "intensity",
62 [IIO_PROXIMITY] = "proximity",
64 [IIO_INCLI] = "incli",
67 [IIO_TIMESTAMP] = "timestamp",
68 [IIO_CAPACITANCE] = "capacitance",
69 [IIO_ALTVOLTAGE] = "altvoltage",
71 [IIO_PRESSURE] = "pressure",
72 [IIO_HUMIDITYRELATIVE] = "humidityrelative",
73 [IIO_ACTIVITY] = "activity",
74 [IIO_STEPS] = "steps",
75 [IIO_ENERGY] = "energy",
76 [IIO_DISTANCE] = "distance",
77 [IIO_VELOCITY] = "velocity",
78 [IIO_CONCENTRATION] = "concentration",
79 [IIO_RESISTANCE] = "resistance",
81 [IIO_UVINDEX] = "uvindex",
82 [IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",
83 [IIO_COUNT] = "count",
84 [IIO_INDEX] = "index",
85 [IIO_GRAVITY] = "gravity",
86 [IIO_POSITIONRELATIVE] = "positionrelative",
87 [IIO_PHASE] = "phase",
88 [IIO_MASSCONCENTRATION] = "massconcentration",
91 static const char * const iio_modifier_names[] = {
95 [IIO_MOD_X_AND_Y] = "x&y",
96 [IIO_MOD_X_AND_Z] = "x&z",
97 [IIO_MOD_Y_AND_Z] = "y&z",
98 [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
99 [IIO_MOD_X_OR_Y] = "x|y",
100 [IIO_MOD_X_OR_Z] = "x|z",
101 [IIO_MOD_Y_OR_Z] = "y|z",
102 [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
103 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
104 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
105 [IIO_MOD_LIGHT_BOTH] = "both",
106 [IIO_MOD_LIGHT_IR] = "ir",
107 [IIO_MOD_LIGHT_CLEAR] = "clear",
108 [IIO_MOD_LIGHT_RED] = "red",
109 [IIO_MOD_LIGHT_GREEN] = "green",
110 [IIO_MOD_LIGHT_BLUE] = "blue",
111 [IIO_MOD_LIGHT_UV] = "uv",
112 [IIO_MOD_LIGHT_DUV] = "duv",
113 [IIO_MOD_QUATERNION] = "quaternion",
114 [IIO_MOD_TEMP_AMBIENT] = "ambient",
115 [IIO_MOD_TEMP_OBJECT] = "object",
116 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
117 [IIO_MOD_NORTH_TRUE] = "from_north_true",
118 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
119 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
120 [IIO_MOD_RUNNING] = "running",
121 [IIO_MOD_JOGGING] = "jogging",
122 [IIO_MOD_WALKING] = "walking",
123 [IIO_MOD_STILL] = "still",
124 [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
127 [IIO_MOD_CO2] = "co2",
128 [IIO_MOD_VOC] = "voc",
129 [IIO_MOD_PM1] = "pm1",
130 [IIO_MOD_PM2P5] = "pm2p5",
131 [IIO_MOD_PM4] = "pm4",
132 [IIO_MOD_PM10] = "pm10",
135 /* relies on pairs of these shared then separate */
136 static const char * const iio_chan_info_postfix[] = {
137 [IIO_CHAN_INFO_RAW] = "raw",
138 [IIO_CHAN_INFO_PROCESSED] = "input",
139 [IIO_CHAN_INFO_SCALE] = "scale",
140 [IIO_CHAN_INFO_OFFSET] = "offset",
141 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
142 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
143 [IIO_CHAN_INFO_PEAK] = "peak_raw",
144 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
145 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
146 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
147 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
148 = "filter_low_pass_3db_frequency",
149 [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
150 = "filter_high_pass_3db_frequency",
151 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
152 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
153 [IIO_CHAN_INFO_PHASE] = "phase",
154 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
155 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
156 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
157 [IIO_CHAN_INFO_ENABLE] = "en",
158 [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
159 [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
160 [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
161 [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
162 [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
163 [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
167 * iio_find_channel_from_si() - get channel from its scan index
169 * @si: scan index to match
171 const struct iio_chan_spec
172 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
176 for (i = 0; i < indio_dev->num_channels; i++)
177 if (indio_dev->channels[i].scan_index == si)
178 return &indio_dev->channels[i];
182 /* This turns up an awful lot */
183 ssize_t iio_read_const_attr(struct device *dev,
184 struct device_attribute *attr,
187 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
189 EXPORT_SYMBOL(iio_read_const_attr);
191 static int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id)
194 const struct iio_event_interface *ev_int = indio_dev->event_interface;
196 ret = mutex_lock_interruptible(&indio_dev->mlock);
199 if ((ev_int && iio_event_enabled(ev_int)) ||
200 iio_buffer_enabled(indio_dev)) {
201 mutex_unlock(&indio_dev->mlock);
204 indio_dev->clock_id = clock_id;
205 mutex_unlock(&indio_dev->mlock);
211 * iio_get_time_ns() - utility function to get a time stamp for events etc
214 s64 iio_get_time_ns(const struct iio_dev *indio_dev)
216 struct timespec64 tp;
218 switch (iio_device_get_clock(indio_dev)) {
220 return ktime_get_real_ns();
221 case CLOCK_MONOTONIC:
222 return ktime_get_ns();
223 case CLOCK_MONOTONIC_RAW:
224 return ktime_get_raw_ns();
225 case CLOCK_REALTIME_COARSE:
226 return ktime_to_ns(ktime_get_coarse_real());
227 case CLOCK_MONOTONIC_COARSE:
228 ktime_get_coarse_ts64(&tp);
229 return timespec64_to_ns(&tp);
231 return ktime_get_boottime_ns();
233 return ktime_get_clocktai_ns();
238 EXPORT_SYMBOL(iio_get_time_ns);
241 * iio_get_time_res() - utility function to get time stamp clock resolution in
245 unsigned int iio_get_time_res(const struct iio_dev *indio_dev)
247 switch (iio_device_get_clock(indio_dev)) {
249 case CLOCK_MONOTONIC:
250 case CLOCK_MONOTONIC_RAW:
253 return hrtimer_resolution;
254 case CLOCK_REALTIME_COARSE:
255 case CLOCK_MONOTONIC_COARSE:
261 EXPORT_SYMBOL(iio_get_time_res);
263 static int __init iio_init(void)
267 /* Register sysfs bus */
268 ret = bus_register(&iio_bus_type);
270 pr_err("could not register bus type\n");
274 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
276 pr_err("failed to allocate char dev region\n");
277 goto error_unregister_bus_type;
280 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
284 error_unregister_bus_type:
285 bus_unregister(&iio_bus_type);
290 static void __exit iio_exit(void)
293 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
294 bus_unregister(&iio_bus_type);
295 debugfs_remove(iio_debugfs_dentry);
298 #if defined(CONFIG_DEBUG_FS)
299 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
300 size_t count, loff_t *ppos)
302 struct iio_dev *indio_dev = file->private_data;
308 ret = indio_dev->info->debugfs_reg_access(indio_dev,
309 indio_dev->cached_reg_addr,
312 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
316 len = snprintf(buf, sizeof(buf), "0x%X\n", val);
318 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
321 static ssize_t iio_debugfs_write_reg(struct file *file,
322 const char __user *userbuf, size_t count, loff_t *ppos)
324 struct iio_dev *indio_dev = file->private_data;
329 count = min_t(size_t, count, (sizeof(buf)-1));
330 if (copy_from_user(buf, userbuf, count))
335 ret = sscanf(buf, "%i %i", ®, &val);
339 indio_dev->cached_reg_addr = reg;
342 indio_dev->cached_reg_addr = reg;
343 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
346 dev_err(indio_dev->dev.parent, "%s: write failed\n",
358 static const struct file_operations iio_debugfs_reg_fops = {
360 .read = iio_debugfs_read_reg,
361 .write = iio_debugfs_write_reg,
364 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
366 debugfs_remove_recursive(indio_dev->debugfs_dentry);
369 static void iio_device_register_debugfs(struct iio_dev *indio_dev)
371 if (indio_dev->info->debugfs_reg_access == NULL)
374 if (!iio_debugfs_dentry)
377 indio_dev->debugfs_dentry =
378 debugfs_create_dir(dev_name(&indio_dev->dev),
381 debugfs_create_file("direct_reg_access", 0644,
382 indio_dev->debugfs_dentry, indio_dev,
383 &iio_debugfs_reg_fops);
386 static void iio_device_register_debugfs(struct iio_dev *indio_dev)
390 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
393 #endif /* CONFIG_DEBUG_FS */
395 static ssize_t iio_read_channel_ext_info(struct device *dev,
396 struct device_attribute *attr,
399 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
400 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
401 const struct iio_chan_spec_ext_info *ext_info;
403 ext_info = &this_attr->c->ext_info[this_attr->address];
405 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
408 static ssize_t iio_write_channel_ext_info(struct device *dev,
409 struct device_attribute *attr,
413 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
414 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
415 const struct iio_chan_spec_ext_info *ext_info;
417 ext_info = &this_attr->c->ext_info[this_attr->address];
419 return ext_info->write(indio_dev, ext_info->private,
420 this_attr->c, buf, len);
423 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
424 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
426 const struct iio_enum *e = (const struct iio_enum *)priv;
433 for (i = 0; i < e->num_items; ++i)
434 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
436 /* replace last space with a newline */
441 EXPORT_SYMBOL_GPL(iio_enum_available_read);
443 ssize_t iio_enum_read(struct iio_dev *indio_dev,
444 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
446 const struct iio_enum *e = (const struct iio_enum *)priv;
452 i = e->get(indio_dev, chan);
455 else if (i >= e->num_items)
458 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
460 EXPORT_SYMBOL_GPL(iio_enum_read);
462 ssize_t iio_enum_write(struct iio_dev *indio_dev,
463 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
466 const struct iio_enum *e = (const struct iio_enum *)priv;
472 ret = __sysfs_match_string(e->items, e->num_items, buf);
476 ret = e->set(indio_dev, chan, ret);
477 return ret ? ret : len;
479 EXPORT_SYMBOL_GPL(iio_enum_write);
481 static const struct iio_mount_matrix iio_mount_idmatrix = {
489 static int iio_setup_mount_idmatrix(const struct device *dev,
490 struct iio_mount_matrix *matrix)
492 *matrix = iio_mount_idmatrix;
493 dev_info(dev, "mounting matrix not found: using identity...\n");
497 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
498 const struct iio_chan_spec *chan, char *buf)
500 const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
501 priv)(indio_dev, chan);
507 mtx = &iio_mount_idmatrix;
509 return snprintf(buf, PAGE_SIZE, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
510 mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
511 mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
512 mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
514 EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
517 * iio_read_mount_matrix() - retrieve iio device mounting matrix from
518 * device "mount-matrix" property
519 * @dev: device the mounting matrix property is assigned to
520 * @propname: device specific mounting matrix property name
521 * @matrix: where to store retrieved matrix
523 * If device is assigned no mounting matrix property, a default 3x3 identity
524 * matrix will be filled in.
526 * Return: 0 if success, or a negative error code on failure.
528 int iio_read_mount_matrix(struct device *dev, const char *propname,
529 struct iio_mount_matrix *matrix)
531 size_t len = ARRAY_SIZE(iio_mount_idmatrix.rotation);
534 err = device_property_read_string_array(dev, propname,
535 matrix->rotation, len);
540 /* Invalid number of matrix entries. */
544 /* Invalid matrix declaration format. */
547 /* Matrix was not declared at all: fallback to identity. */
548 return iio_setup_mount_idmatrix(dev, matrix);
550 EXPORT_SYMBOL(iio_read_mount_matrix);
552 static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
553 int size, const int *vals)
555 unsigned long long tmp;
557 bool scale_db = false;
561 return snprintf(buf, len, "%d", vals[0]);
562 case IIO_VAL_INT_PLUS_MICRO_DB:
565 case IIO_VAL_INT_PLUS_MICRO:
567 return snprintf(buf, len, "-%d.%06u%s", abs(vals[0]),
568 -vals[1], scale_db ? " dB" : "");
570 return snprintf(buf, len, "%d.%06u%s", vals[0], vals[1],
571 scale_db ? " dB" : "");
572 case IIO_VAL_INT_PLUS_NANO:
574 return snprintf(buf, len, "-%d.%09u", abs(vals[0]),
577 return snprintf(buf, len, "%d.%09u", vals[0], vals[1]);
578 case IIO_VAL_FRACTIONAL:
579 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
581 tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
582 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
583 case IIO_VAL_FRACTIONAL_LOG2:
584 tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
585 tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
586 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
587 case IIO_VAL_INT_MULTIPLE:
592 for (i = 0; i < size; ++i) {
593 l += snprintf(&buf[l], len - l, "%d ", vals[i]);
605 * iio_format_value() - Formats a IIO value into its string representation
606 * @buf: The buffer to which the formatted value gets written
607 * which is assumed to be big enough (i.e. PAGE_SIZE).
608 * @type: One of the IIO_VAL_* constants. This decides how the val
609 * and val2 parameters are formatted.
610 * @size: Number of IIO value entries contained in vals
611 * @vals: Pointer to the values, exact meaning depends on the
614 * Return: 0 by default, a negative number on failure or the
615 * total number of characters written for a type that belongs
616 * to the IIO_VAL_* constant.
618 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
622 len = __iio_format_value(buf, PAGE_SIZE, type, size, vals);
623 if (len >= PAGE_SIZE - 1)
626 return len + sprintf(buf + len, "\n");
628 EXPORT_SYMBOL_GPL(iio_format_value);
630 static ssize_t iio_read_channel_info(struct device *dev,
631 struct device_attribute *attr,
634 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
635 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
636 int vals[INDIO_MAX_RAW_ELEMENTS];
640 if (indio_dev->info->read_raw_multi)
641 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
642 INDIO_MAX_RAW_ELEMENTS,
646 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
647 &vals[0], &vals[1], this_attr->address);
652 return iio_format_value(buf, ret, val_len, vals);
655 static ssize_t iio_format_avail_list(char *buf, const int *vals,
656 int type, int length)
663 for (i = 0; i < length; i++) {
664 len += __iio_format_value(buf + len, PAGE_SIZE - len,
666 if (len >= PAGE_SIZE)
669 len += snprintf(buf + len, PAGE_SIZE - len,
672 len += snprintf(buf + len, PAGE_SIZE - len,
674 if (len >= PAGE_SIZE)
679 for (i = 0; i < length / 2; i++) {
680 len += __iio_format_value(buf + len, PAGE_SIZE - len,
681 type, 2, &vals[i * 2]);
682 if (len >= PAGE_SIZE)
684 if (i < length / 2 - 1)
685 len += snprintf(buf + len, PAGE_SIZE - len,
688 len += snprintf(buf + len, PAGE_SIZE - len,
690 if (len >= PAGE_SIZE)
698 static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
703 len = snprintf(buf, PAGE_SIZE, "[");
706 for (i = 0; i < 3; i++) {
707 len += __iio_format_value(buf + len, PAGE_SIZE - len,
709 if (len >= PAGE_SIZE)
712 len += snprintf(buf + len, PAGE_SIZE - len,
715 len += snprintf(buf + len, PAGE_SIZE - len,
717 if (len >= PAGE_SIZE)
722 for (i = 0; i < 3; i++) {
723 len += __iio_format_value(buf + len, PAGE_SIZE - len,
724 type, 2, &vals[i * 2]);
725 if (len >= PAGE_SIZE)
728 len += snprintf(buf + len, PAGE_SIZE - len,
731 len += snprintf(buf + len, PAGE_SIZE - len,
733 if (len >= PAGE_SIZE)
741 static ssize_t iio_read_channel_info_avail(struct device *dev,
742 struct device_attribute *attr,
745 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
746 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
752 ret = indio_dev->info->read_avail(indio_dev, this_attr->c,
753 &vals, &type, &length,
760 return iio_format_avail_list(buf, vals, type, length);
761 case IIO_AVAIL_RANGE:
762 return iio_format_avail_range(buf, vals, type);
769 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
770 * @str: The string to parse
771 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
772 * @integer: The integer part of the number
773 * @fract: The fractional part of the number
775 * Returns 0 on success, or a negative error code if the string could not be
778 int iio_str_to_fixpoint(const char *str, int fract_mult,
779 int *integer, int *fract)
782 bool integer_part = true, negative = false;
784 if (fract_mult == 0) {
787 return kstrtoint(str, 0, integer);
793 } else if (str[0] == '+') {
798 if ('0' <= *str && *str <= '9') {
800 i = i * 10 + *str - '0';
802 f += fract_mult * (*str - '0');
805 } else if (*str == '\n') {
806 if (*(str + 1) == '\0')
810 } else if (*str == '.' && integer_part) {
811 integer_part = false;
830 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
832 static ssize_t iio_write_channel_info(struct device *dev,
833 struct device_attribute *attr,
837 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
838 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
839 int ret, fract_mult = 100000;
842 /* Assumes decimal - precision based on number of digits */
843 if (!indio_dev->info->write_raw)
846 if (indio_dev->info->write_raw_get_fmt)
847 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
848 this_attr->c, this_attr->address)) {
852 case IIO_VAL_INT_PLUS_MICRO:
855 case IIO_VAL_INT_PLUS_NANO:
856 fract_mult = 100000000;
862 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
866 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
867 integer, fract, this_attr->address);
875 int __iio_device_attr_init(struct device_attribute *dev_attr,
877 struct iio_chan_spec const *chan,
878 ssize_t (*readfunc)(struct device *dev,
879 struct device_attribute *attr,
881 ssize_t (*writefunc)(struct device *dev,
882 struct device_attribute *attr,
885 enum iio_shared_by shared_by)
890 sysfs_attr_init(&dev_attr->attr);
892 /* Build up postfix of <extend_name>_<modifier>_postfix */
893 if (chan->modified && (shared_by == IIO_SEPARATE)) {
894 if (chan->extend_name)
895 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
896 iio_modifier_names[chan
901 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
902 iio_modifier_names[chan
906 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
907 full_postfix = kstrdup(postfix, GFP_KERNEL);
909 full_postfix = kasprintf(GFP_KERNEL,
914 if (full_postfix == NULL)
917 if (chan->differential) { /* Differential can not have modifier */
919 case IIO_SHARED_BY_ALL:
920 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
922 case IIO_SHARED_BY_DIR:
923 name = kasprintf(GFP_KERNEL, "%s_%s",
924 iio_direction[chan->output],
927 case IIO_SHARED_BY_TYPE:
928 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
929 iio_direction[chan->output],
930 iio_chan_type_name_spec[chan->type],
931 iio_chan_type_name_spec[chan->type],
935 if (!chan->indexed) {
936 WARN(1, "Differential channels must be indexed\n");
938 goto error_free_full_postfix;
940 name = kasprintf(GFP_KERNEL,
942 iio_direction[chan->output],
943 iio_chan_type_name_spec[chan->type],
945 iio_chan_type_name_spec[chan->type],
950 } else { /* Single ended */
952 case IIO_SHARED_BY_ALL:
953 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
955 case IIO_SHARED_BY_DIR:
956 name = kasprintf(GFP_KERNEL, "%s_%s",
957 iio_direction[chan->output],
960 case IIO_SHARED_BY_TYPE:
961 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
962 iio_direction[chan->output],
963 iio_chan_type_name_spec[chan->type],
969 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
970 iio_direction[chan->output],
971 iio_chan_type_name_spec[chan->type],
975 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
976 iio_direction[chan->output],
977 iio_chan_type_name_spec[chan->type],
984 goto error_free_full_postfix;
986 dev_attr->attr.name = name;
989 dev_attr->attr.mode |= S_IRUGO;
990 dev_attr->show = readfunc;
994 dev_attr->attr.mode |= S_IWUSR;
995 dev_attr->store = writefunc;
998 error_free_full_postfix:
1004 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
1006 kfree(dev_attr->attr.name);
1009 int __iio_add_chan_devattr(const char *postfix,
1010 struct iio_chan_spec const *chan,
1011 ssize_t (*readfunc)(struct device *dev,
1012 struct device_attribute *attr,
1014 ssize_t (*writefunc)(struct device *dev,
1015 struct device_attribute *attr,
1019 enum iio_shared_by shared_by,
1021 struct list_head *attr_list)
1024 struct iio_dev_attr *iio_attr, *t;
1026 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
1027 if (iio_attr == NULL)
1029 ret = __iio_device_attr_init(&iio_attr->dev_attr,
1031 readfunc, writefunc, shared_by);
1033 goto error_iio_dev_attr_free;
1035 iio_attr->address = mask;
1036 list_for_each_entry(t, attr_list, l)
1037 if (strcmp(t->dev_attr.attr.name,
1038 iio_attr->dev_attr.attr.name) == 0) {
1039 if (shared_by == IIO_SEPARATE)
1040 dev_err(dev, "tried to double register : %s\n",
1041 t->dev_attr.attr.name);
1043 goto error_device_attr_deinit;
1045 list_add(&iio_attr->l, attr_list);
1049 error_device_attr_deinit:
1050 __iio_device_attr_deinit(&iio_attr->dev_attr);
1051 error_iio_dev_attr_free:
1056 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
1057 struct iio_chan_spec const *chan,
1058 enum iio_shared_by shared_by,
1059 const long *infomask)
1061 int i, ret, attrcount = 0;
1063 for_each_set_bit(i, infomask, sizeof(*infomask)*8) {
1064 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1066 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
1068 &iio_read_channel_info,
1069 &iio_write_channel_info,
1073 &indio_dev->channel_attr_list);
1074 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1084 static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
1085 struct iio_chan_spec const *chan,
1086 enum iio_shared_by shared_by,
1087 const long *infomask)
1089 int i, ret, attrcount = 0;
1090 char *avail_postfix;
1092 for_each_set_bit(i, infomask, sizeof(*infomask) * 8) {
1093 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1095 avail_postfix = kasprintf(GFP_KERNEL,
1097 iio_chan_info_postfix[i]);
1101 ret = __iio_add_chan_devattr(avail_postfix,
1103 &iio_read_channel_info_avail,
1108 &indio_dev->channel_attr_list);
1109 kfree(avail_postfix);
1110 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1120 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
1121 struct iio_chan_spec const *chan)
1123 int ret, attrcount = 0;
1124 const struct iio_chan_spec_ext_info *ext_info;
1126 if (chan->channel < 0)
1128 ret = iio_device_add_info_mask_type(indio_dev, chan,
1130 &chan->info_mask_separate);
1135 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1138 info_mask_separate_available);
1143 ret = iio_device_add_info_mask_type(indio_dev, chan,
1145 &chan->info_mask_shared_by_type);
1150 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1153 info_mask_shared_by_type_available);
1158 ret = iio_device_add_info_mask_type(indio_dev, chan,
1160 &chan->info_mask_shared_by_dir);
1165 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1167 &chan->info_mask_shared_by_dir_available);
1172 ret = iio_device_add_info_mask_type(indio_dev, chan,
1174 &chan->info_mask_shared_by_all);
1179 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1181 &chan->info_mask_shared_by_all_available);
1186 if (chan->ext_info) {
1188 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
1189 ret = __iio_add_chan_devattr(ext_info->name,
1192 &iio_read_channel_ext_info : NULL,
1194 &iio_write_channel_ext_info : NULL,
1198 &indio_dev->channel_attr_list);
1200 if (ret == -EBUSY && ext_info->shared)
1214 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
1215 * @attr_list: List of IIO device attributes
1217 * This function frees the memory allocated for each of the IIO device
1218 * attributes in the list.
1220 void iio_free_chan_devattr_list(struct list_head *attr_list)
1222 struct iio_dev_attr *p, *n;
1224 list_for_each_entry_safe(p, n, attr_list, l) {
1225 kfree(p->dev_attr.attr.name);
1231 static ssize_t iio_show_dev_name(struct device *dev,
1232 struct device_attribute *attr,
1235 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1236 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
1239 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
1241 static ssize_t iio_show_dev_label(struct device *dev,
1242 struct device_attribute *attr,
1245 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1246 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->label);
1249 static DEVICE_ATTR(label, S_IRUGO, iio_show_dev_label, NULL);
1251 static ssize_t iio_show_timestamp_clock(struct device *dev,
1252 struct device_attribute *attr,
1255 const struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1256 const clockid_t clk = iio_device_get_clock(indio_dev);
1261 case CLOCK_REALTIME:
1262 name = "realtime\n";
1263 sz = sizeof("realtime\n");
1265 case CLOCK_MONOTONIC:
1266 name = "monotonic\n";
1267 sz = sizeof("monotonic\n");
1269 case CLOCK_MONOTONIC_RAW:
1270 name = "monotonic_raw\n";
1271 sz = sizeof("monotonic_raw\n");
1273 case CLOCK_REALTIME_COARSE:
1274 name = "realtime_coarse\n";
1275 sz = sizeof("realtime_coarse\n");
1277 case CLOCK_MONOTONIC_COARSE:
1278 name = "monotonic_coarse\n";
1279 sz = sizeof("monotonic_coarse\n");
1281 case CLOCK_BOOTTIME:
1282 name = "boottime\n";
1283 sz = sizeof("boottime\n");
1287 sz = sizeof("tai\n");
1293 memcpy(buf, name, sz);
1297 static ssize_t iio_store_timestamp_clock(struct device *dev,
1298 struct device_attribute *attr,
1299 const char *buf, size_t len)
1304 if (sysfs_streq(buf, "realtime"))
1305 clk = CLOCK_REALTIME;
1306 else if (sysfs_streq(buf, "monotonic"))
1307 clk = CLOCK_MONOTONIC;
1308 else if (sysfs_streq(buf, "monotonic_raw"))
1309 clk = CLOCK_MONOTONIC_RAW;
1310 else if (sysfs_streq(buf, "realtime_coarse"))
1311 clk = CLOCK_REALTIME_COARSE;
1312 else if (sysfs_streq(buf, "monotonic_coarse"))
1313 clk = CLOCK_MONOTONIC_COARSE;
1314 else if (sysfs_streq(buf, "boottime"))
1315 clk = CLOCK_BOOTTIME;
1316 else if (sysfs_streq(buf, "tai"))
1321 ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);
1328 static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
1329 iio_show_timestamp_clock, iio_store_timestamp_clock);
1331 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
1333 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
1334 struct iio_dev_attr *p;
1335 struct attribute **attr, *clk = NULL;
1337 /* First count elements in any existing group */
1338 if (indio_dev->info->attrs) {
1339 attr = indio_dev->info->attrs->attrs;
1340 while (*attr++ != NULL)
1343 attrcount = attrcount_orig;
1345 * New channel registration method - relies on the fact a group does
1346 * not need to be initialized if its name is NULL.
1348 if (indio_dev->channels)
1349 for (i = 0; i < indio_dev->num_channels; i++) {
1350 const struct iio_chan_spec *chan =
1351 &indio_dev->channels[i];
1353 if (chan->type == IIO_TIMESTAMP)
1354 clk = &dev_attr_current_timestamp_clock.attr;
1356 ret = iio_device_add_channel_sysfs(indio_dev, chan);
1358 goto error_clear_attrs;
1362 if (indio_dev->event_interface)
1363 clk = &dev_attr_current_timestamp_clock.attr;
1365 if (indio_dev->name)
1367 if (indio_dev->label)
1372 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
1373 sizeof(indio_dev->chan_attr_group.attrs[0]),
1375 if (indio_dev->chan_attr_group.attrs == NULL) {
1377 goto error_clear_attrs;
1379 /* Copy across original attributes */
1380 if (indio_dev->info->attrs)
1381 memcpy(indio_dev->chan_attr_group.attrs,
1382 indio_dev->info->attrs->attrs,
1383 sizeof(indio_dev->chan_attr_group.attrs[0])
1385 attrn = attrcount_orig;
1386 /* Add all elements from the list. */
1387 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
1388 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
1389 if (indio_dev->name)
1390 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
1391 if (indio_dev->label)
1392 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_label.attr;
1394 indio_dev->chan_attr_group.attrs[attrn++] = clk;
1396 indio_dev->groups[indio_dev->groupcounter++] =
1397 &indio_dev->chan_attr_group;
1402 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1407 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
1410 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1411 kfree(indio_dev->chan_attr_group.attrs);
1412 indio_dev->chan_attr_group.attrs = NULL;
1415 static void iio_dev_release(struct device *device)
1417 struct iio_dev *indio_dev = dev_to_iio_dev(device);
1418 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1419 iio_device_unregister_trigger_consumer(indio_dev);
1420 iio_device_unregister_eventset(indio_dev);
1421 iio_device_unregister_sysfs(indio_dev);
1423 iio_buffer_put(indio_dev->buffer);
1425 ida_simple_remove(&iio_ida, indio_dev->id);
1429 struct device_type iio_device_type = {
1430 .name = "iio_device",
1431 .release = iio_dev_release,
1435 * iio_device_alloc() - allocate an iio_dev from a driver
1436 * @sizeof_priv: Space to allocate for private structure.
1438 struct iio_dev *iio_device_alloc(int sizeof_priv)
1440 struct iio_dev *dev;
1443 alloc_size = sizeof(struct iio_dev);
1445 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1446 alloc_size += sizeof_priv;
1448 /* ensure 32-byte alignment of whole construct ? */
1449 alloc_size += IIO_ALIGN - 1;
1451 dev = kzalloc(alloc_size, GFP_KERNEL);
1454 dev->dev.groups = dev->groups;
1455 dev->dev.type = &iio_device_type;
1456 dev->dev.bus = &iio_bus_type;
1457 device_initialize(&dev->dev);
1458 dev_set_drvdata(&dev->dev, (void *)dev);
1459 mutex_init(&dev->mlock);
1460 mutex_init(&dev->info_exist_lock);
1461 INIT_LIST_HEAD(&dev->channel_attr_list);
1463 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1465 /* cannot use a dev_err as the name isn't available */
1466 pr_err("failed to get device id\n");
1470 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1471 INIT_LIST_HEAD(&dev->buffer_list);
1476 EXPORT_SYMBOL(iio_device_alloc);
1479 * iio_device_free() - free an iio_dev from a driver
1480 * @dev: the iio_dev associated with the device
1482 void iio_device_free(struct iio_dev *dev)
1485 put_device(&dev->dev);
1487 EXPORT_SYMBOL(iio_device_free);
1489 static void devm_iio_device_release(struct device *dev, void *res)
1491 iio_device_free(*(struct iio_dev **)res);
1494 int devm_iio_device_match(struct device *dev, void *res, void *data)
1496 struct iio_dev **r = res;
1503 EXPORT_SYMBOL_GPL(devm_iio_device_match);
1506 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1507 * @dev: Device to allocate iio_dev for
1508 * @sizeof_priv: Space to allocate for private structure.
1510 * Managed iio_device_alloc. iio_dev allocated with this function is
1511 * automatically freed on driver detach.
1513 * If an iio_dev allocated with this function needs to be freed separately,
1514 * devm_iio_device_free() must be used.
1517 * Pointer to allocated iio_dev on success, NULL on failure.
1519 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1521 struct iio_dev **ptr, *iio_dev;
1523 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1528 iio_dev = iio_device_alloc(sizeof_priv);
1531 devres_add(dev, ptr);
1538 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1541 * devm_iio_device_free - Resource-managed iio_device_free()
1542 * @dev: Device this iio_dev belongs to
1543 * @iio_dev: the iio_dev associated with the device
1545 * Free iio_dev allocated with devm_iio_device_alloc().
1547 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1551 rc = devres_release(dev, devm_iio_device_release,
1552 devm_iio_device_match, iio_dev);
1555 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1558 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1559 * @inode: Inode structure for identifying the device in the file system
1560 * @filp: File structure for iio device used to keep and later access
1563 * Return: 0 on success or -EBUSY if the device is already opened
1565 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1567 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1568 struct iio_dev, chrdev);
1570 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1573 iio_device_get(indio_dev);
1575 filp->private_data = indio_dev;
1581 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1582 * @inode: Inode structure pointer for the char device
1583 * @filp: File structure pointer for the char device
1585 * Return: 0 for successful release
1587 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1589 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1590 struct iio_dev, chrdev);
1591 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1592 iio_device_put(indio_dev);
1597 /* Somewhat of a cross file organization violation - ioctls here are actually
1599 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1601 struct iio_dev *indio_dev = filp->private_data;
1602 int __user *ip = (int __user *)arg;
1605 if (!indio_dev->info)
1608 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1609 fd = iio_event_getfd(indio_dev);
1612 if (copy_to_user(ip, &fd, sizeof(fd)))
1619 static const struct file_operations iio_buffer_fileops = {
1620 .read = iio_buffer_read_first_n_outer_addr,
1621 .release = iio_chrdev_release,
1622 .open = iio_chrdev_open,
1623 .poll = iio_buffer_poll_addr,
1624 .owner = THIS_MODULE,
1625 .llseek = noop_llseek,
1626 .unlocked_ioctl = iio_ioctl,
1627 .compat_ioctl = compat_ptr_ioctl,
1630 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1633 const struct iio_chan_spec *channels = indio_dev->channels;
1635 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1638 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1639 if (channels[i].scan_index < 0)
1641 for (j = i + 1; j < indio_dev->num_channels; j++)
1642 if (channels[i].scan_index == channels[j].scan_index) {
1643 dev_err(&indio_dev->dev,
1644 "Duplicate scan index %d\n",
1645 channels[i].scan_index);
1653 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1655 int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
1659 indio_dev->driver_module = this_mod;
1660 /* If the calling driver did not initialize of_node, do it here */
1661 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1662 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1664 indio_dev->label = of_get_property(indio_dev->dev.of_node, "label",
1667 ret = iio_check_unique_scan_index(indio_dev);
1671 if (!indio_dev->info)
1674 /* configure elements for the chrdev */
1675 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1677 iio_device_register_debugfs(indio_dev);
1679 ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1681 dev_err(indio_dev->dev.parent,
1682 "Failed to create buffer sysfs interfaces\n");
1683 goto error_unreg_debugfs;
1686 ret = iio_device_register_sysfs(indio_dev);
1688 dev_err(indio_dev->dev.parent,
1689 "Failed to register sysfs interfaces\n");
1690 goto error_buffer_free_sysfs;
1692 ret = iio_device_register_eventset(indio_dev);
1694 dev_err(indio_dev->dev.parent,
1695 "Failed to register event set\n");
1696 goto error_free_sysfs;
1698 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1699 iio_device_register_trigger_consumer(indio_dev);
1701 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1702 indio_dev->setup_ops == NULL)
1703 indio_dev->setup_ops = &noop_ring_setup_ops;
1705 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1707 indio_dev->chrdev.owner = this_mod;
1709 ret = cdev_device_add(&indio_dev->chrdev, &indio_dev->dev);
1711 goto error_unreg_eventset;
1715 error_unreg_eventset:
1716 iio_device_unregister_eventset(indio_dev);
1718 iio_device_unregister_sysfs(indio_dev);
1719 error_buffer_free_sysfs:
1720 iio_buffer_free_sysfs_and_mask(indio_dev);
1721 error_unreg_debugfs:
1722 iio_device_unregister_debugfs(indio_dev);
1725 EXPORT_SYMBOL(__iio_device_register);
1728 * iio_device_unregister() - unregister a device from the IIO subsystem
1729 * @indio_dev: Device structure representing the device.
1731 void iio_device_unregister(struct iio_dev *indio_dev)
1733 cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
1735 mutex_lock(&indio_dev->info_exist_lock);
1737 iio_device_unregister_debugfs(indio_dev);
1739 iio_disable_all_buffers(indio_dev);
1741 indio_dev->info = NULL;
1743 iio_device_wakeup_eventset(indio_dev);
1744 iio_buffer_wakeup_poll(indio_dev);
1746 mutex_unlock(&indio_dev->info_exist_lock);
1748 iio_buffer_free_sysfs_and_mask(indio_dev);
1750 EXPORT_SYMBOL(iio_device_unregister);
1752 static void devm_iio_device_unreg(struct device *dev, void *res)
1754 iio_device_unregister(*(struct iio_dev **)res);
1757 int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,
1758 struct module *this_mod)
1760 struct iio_dev **ptr;
1763 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1768 ret = __iio_device_register(indio_dev, this_mod);
1770 devres_add(dev, ptr);
1776 EXPORT_SYMBOL_GPL(__devm_iio_device_register);
1779 * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1780 * @dev: Device this iio_dev belongs to
1781 * @indio_dev: the iio_dev associated with the device
1783 * Unregister iio_dev registered with devm_iio_device_register().
1785 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1789 rc = devres_release(dev, devm_iio_device_unreg,
1790 devm_iio_device_match, indio_dev);
1793 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1796 * iio_device_claim_direct_mode - Keep device in direct mode
1797 * @indio_dev: the iio_dev associated with the device
1799 * If the device is in direct mode it is guaranteed to stay
1800 * that way until iio_device_release_direct_mode() is called.
1802 * Use with iio_device_release_direct_mode()
1804 * Returns: 0 on success, -EBUSY on failure
1806 int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
1808 mutex_lock(&indio_dev->mlock);
1810 if (iio_buffer_enabled(indio_dev)) {
1811 mutex_unlock(&indio_dev->mlock);
1816 EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
1819 * iio_device_release_direct_mode - releases claim on direct mode
1820 * @indio_dev: the iio_dev associated with the device
1822 * Release the claim. Device is no longer guaranteed to stay
1825 * Use with iio_device_claim_direct_mode()
1827 void iio_device_release_direct_mode(struct iio_dev *indio_dev)
1829 mutex_unlock(&indio_dev->mlock);
1831 EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
1833 subsys_initcall(iio_init);
1834 module_exit(iio_exit);
1836 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1837 MODULE_DESCRIPTION("Industrial I/O core");
1838 MODULE_LICENSE("GPL");