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__);
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 int iio_device_register_debugfs(struct iio_dev *indio_dev)
373 if (indio_dev->info->debugfs_reg_access == NULL)
376 if (!iio_debugfs_dentry)
379 indio_dev->debugfs_dentry =
380 debugfs_create_dir(dev_name(&indio_dev->dev),
382 if (indio_dev->debugfs_dentry == NULL) {
383 dev_warn(indio_dev->dev.parent,
384 "Failed to create debugfs directory\n");
388 d = debugfs_create_file("direct_reg_access", 0644,
389 indio_dev->debugfs_dentry,
390 indio_dev, &iio_debugfs_reg_fops);
392 iio_device_unregister_debugfs(indio_dev);
399 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
404 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
407 #endif /* CONFIG_DEBUG_FS */
409 static ssize_t iio_read_channel_ext_info(struct device *dev,
410 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->read(indio_dev, ext_info->private, this_attr->c, buf);
422 static ssize_t iio_write_channel_ext_info(struct device *dev,
423 struct device_attribute *attr,
427 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
428 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
429 const struct iio_chan_spec_ext_info *ext_info;
431 ext_info = &this_attr->c->ext_info[this_attr->address];
433 return ext_info->write(indio_dev, ext_info->private,
434 this_attr->c, buf, len);
437 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
438 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
440 const struct iio_enum *e = (const struct iio_enum *)priv;
447 for (i = 0; i < e->num_items; ++i)
448 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
450 /* replace last space with a newline */
455 EXPORT_SYMBOL_GPL(iio_enum_available_read);
457 ssize_t iio_enum_read(struct iio_dev *indio_dev,
458 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
460 const struct iio_enum *e = (const struct iio_enum *)priv;
466 i = e->get(indio_dev, chan);
469 else if (i >= e->num_items)
472 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
474 EXPORT_SYMBOL_GPL(iio_enum_read);
476 ssize_t iio_enum_write(struct iio_dev *indio_dev,
477 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
480 const struct iio_enum *e = (const struct iio_enum *)priv;
486 ret = __sysfs_match_string(e->items, e->num_items, buf);
490 ret = e->set(indio_dev, chan, ret);
491 return ret ? ret : len;
493 EXPORT_SYMBOL_GPL(iio_enum_write);
495 static const struct iio_mount_matrix iio_mount_idmatrix = {
503 static int iio_setup_mount_idmatrix(const struct device *dev,
504 struct iio_mount_matrix *matrix)
506 *matrix = iio_mount_idmatrix;
507 dev_info(dev, "mounting matrix not found: using identity...\n");
511 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
512 const struct iio_chan_spec *chan, char *buf)
514 const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
515 priv)(indio_dev, chan);
521 mtx = &iio_mount_idmatrix;
523 return snprintf(buf, PAGE_SIZE, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
524 mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
525 mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
526 mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
528 EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
531 * of_iio_read_mount_matrix() - retrieve iio device mounting matrix from
532 * device-tree "mount-matrix" property
533 * @dev: device the mounting matrix property is assigned to
534 * @propname: device specific mounting matrix property name
535 * @matrix: where to store retrieved matrix
537 * If device is assigned no mounting matrix property, a default 3x3 identity
538 * matrix will be filled in.
540 * Return: 0 if success, or a negative error code on failure.
543 int of_iio_read_mount_matrix(const struct device *dev,
544 const char *propname,
545 struct iio_mount_matrix *matrix)
548 int err = of_property_read_string_array(dev->of_node,
549 propname, matrix->rotation,
550 ARRAY_SIZE(iio_mount_idmatrix.rotation));
552 if (err == ARRAY_SIZE(iio_mount_idmatrix.rotation))
556 /* Invalid number of matrix entries. */
560 /* Invalid matrix declaration format. */
564 /* Matrix was not declared at all: fallback to identity. */
565 return iio_setup_mount_idmatrix(dev, matrix);
568 int of_iio_read_mount_matrix(const struct device *dev,
569 const char *propname,
570 struct iio_mount_matrix *matrix)
572 return iio_setup_mount_idmatrix(dev, matrix);
575 EXPORT_SYMBOL(of_iio_read_mount_matrix);
577 static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
578 int size, const int *vals)
580 unsigned long long tmp;
582 bool scale_db = false;
586 return snprintf(buf, len, "%d", vals[0]);
587 case IIO_VAL_INT_PLUS_MICRO_DB:
589 case IIO_VAL_INT_PLUS_MICRO:
591 return snprintf(buf, len, "-%d.%06u%s", abs(vals[0]),
592 -vals[1], scale_db ? " dB" : "");
594 return snprintf(buf, len, "%d.%06u%s", vals[0], vals[1],
595 scale_db ? " dB" : "");
596 case IIO_VAL_INT_PLUS_NANO:
598 return snprintf(buf, len, "-%d.%09u", abs(vals[0]),
601 return snprintf(buf, len, "%d.%09u", vals[0], vals[1]);
602 case IIO_VAL_FRACTIONAL:
603 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
605 tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
606 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
607 case IIO_VAL_FRACTIONAL_LOG2:
608 tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
609 tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
610 return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
611 case IIO_VAL_INT_MULTIPLE:
616 for (i = 0; i < size; ++i) {
617 l += snprintf(&buf[l], len - l, "%d ", vals[i]);
629 * iio_format_value() - Formats a IIO value into its string representation
630 * @buf: The buffer to which the formatted value gets written
631 * which is assumed to be big enough (i.e. PAGE_SIZE).
632 * @type: One of the IIO_VAL_... constants. This decides how the val
633 * and val2 parameters are formatted.
634 * @size: Number of IIO value entries contained in vals
635 * @vals: Pointer to the values, exact meaning depends on the
638 * Return: 0 by default, a negative number on failure or the
639 * total number of characters written for a type that belongs
640 * to the IIO_VAL_... constant.
642 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
646 len = __iio_format_value(buf, PAGE_SIZE, type, size, vals);
647 if (len >= PAGE_SIZE - 1)
650 return len + sprintf(buf + len, "\n");
652 EXPORT_SYMBOL_GPL(iio_format_value);
654 static ssize_t iio_read_channel_info(struct device *dev,
655 struct device_attribute *attr,
658 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
659 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
660 int vals[INDIO_MAX_RAW_ELEMENTS];
664 if (indio_dev->info->read_raw_multi)
665 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
666 INDIO_MAX_RAW_ELEMENTS,
670 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
671 &vals[0], &vals[1], this_attr->address);
676 return iio_format_value(buf, ret, val_len, vals);
679 static ssize_t iio_format_avail_list(char *buf, const int *vals,
680 int type, int length)
687 for (i = 0; i < length; i++) {
688 len += __iio_format_value(buf + len, PAGE_SIZE - len,
690 if (len >= PAGE_SIZE)
693 len += snprintf(buf + len, PAGE_SIZE - len,
696 len += snprintf(buf + len, PAGE_SIZE - len,
698 if (len >= PAGE_SIZE)
703 for (i = 0; i < length / 2; i++) {
704 len += __iio_format_value(buf + len, PAGE_SIZE - len,
705 type, 2, &vals[i * 2]);
706 if (len >= PAGE_SIZE)
708 if (i < length / 2 - 1)
709 len += snprintf(buf + len, PAGE_SIZE - len,
712 len += snprintf(buf + len, PAGE_SIZE - len,
714 if (len >= PAGE_SIZE)
722 static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
727 len = snprintf(buf, PAGE_SIZE, "[");
730 for (i = 0; i < 3; i++) {
731 len += __iio_format_value(buf + len, PAGE_SIZE - len,
733 if (len >= PAGE_SIZE)
736 len += snprintf(buf + len, PAGE_SIZE - len,
739 len += snprintf(buf + len, PAGE_SIZE - len,
741 if (len >= PAGE_SIZE)
746 for (i = 0; i < 3; i++) {
747 len += __iio_format_value(buf + len, PAGE_SIZE - len,
748 type, 2, &vals[i * 2]);
749 if (len >= PAGE_SIZE)
752 len += snprintf(buf + len, PAGE_SIZE - len,
755 len += snprintf(buf + len, PAGE_SIZE - len,
757 if (len >= PAGE_SIZE)
765 static ssize_t iio_read_channel_info_avail(struct device *dev,
766 struct device_attribute *attr,
769 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
770 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
776 ret = indio_dev->info->read_avail(indio_dev, this_attr->c,
777 &vals, &type, &length,
784 return iio_format_avail_list(buf, vals, type, length);
785 case IIO_AVAIL_RANGE:
786 return iio_format_avail_range(buf, vals, type);
793 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
794 * @str: The string to parse
795 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
796 * @integer: The integer part of the number
797 * @fract: The fractional part of the number
799 * Returns 0 on success, or a negative error code if the string could not be
802 int iio_str_to_fixpoint(const char *str, int fract_mult,
803 int *integer, int *fract)
806 bool integer_part = true, negative = false;
808 if (fract_mult == 0) {
811 return kstrtoint(str, 0, integer);
817 } else if (str[0] == '+') {
822 if ('0' <= *str && *str <= '9') {
824 i = i * 10 + *str - '0';
826 f += fract_mult * (*str - '0');
829 } else if (*str == '\n') {
830 if (*(str + 1) == '\0')
834 } else if (*str == '.' && integer_part) {
835 integer_part = false;
854 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
856 static ssize_t iio_write_channel_info(struct device *dev,
857 struct device_attribute *attr,
861 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
862 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
863 int ret, fract_mult = 100000;
866 /* Assumes decimal - precision based on number of digits */
867 if (!indio_dev->info->write_raw)
870 if (indio_dev->info->write_raw_get_fmt)
871 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
872 this_attr->c, this_attr->address)) {
876 case IIO_VAL_INT_PLUS_MICRO:
879 case IIO_VAL_INT_PLUS_NANO:
880 fract_mult = 100000000;
886 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
890 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
891 integer, fract, this_attr->address);
899 int __iio_device_attr_init(struct device_attribute *dev_attr,
901 struct iio_chan_spec const *chan,
902 ssize_t (*readfunc)(struct device *dev,
903 struct device_attribute *attr,
905 ssize_t (*writefunc)(struct device *dev,
906 struct device_attribute *attr,
909 enum iio_shared_by shared_by)
914 sysfs_attr_init(&dev_attr->attr);
916 /* Build up postfix of <extend_name>_<modifier>_postfix */
917 if (chan->modified && (shared_by == IIO_SEPARATE)) {
918 if (chan->extend_name)
919 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
920 iio_modifier_names[chan
925 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
926 iio_modifier_names[chan
930 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
931 full_postfix = kstrdup(postfix, GFP_KERNEL);
933 full_postfix = kasprintf(GFP_KERNEL,
938 if (full_postfix == NULL)
941 if (chan->differential) { /* Differential can not have modifier */
943 case IIO_SHARED_BY_ALL:
944 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
946 case IIO_SHARED_BY_DIR:
947 name = kasprintf(GFP_KERNEL, "%s_%s",
948 iio_direction[chan->output],
951 case IIO_SHARED_BY_TYPE:
952 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
953 iio_direction[chan->output],
954 iio_chan_type_name_spec[chan->type],
955 iio_chan_type_name_spec[chan->type],
959 if (!chan->indexed) {
960 WARN(1, "Differential channels must be indexed\n");
962 goto error_free_full_postfix;
964 name = kasprintf(GFP_KERNEL,
966 iio_direction[chan->output],
967 iio_chan_type_name_spec[chan->type],
969 iio_chan_type_name_spec[chan->type],
974 } else { /* Single ended */
976 case IIO_SHARED_BY_ALL:
977 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
979 case IIO_SHARED_BY_DIR:
980 name = kasprintf(GFP_KERNEL, "%s_%s",
981 iio_direction[chan->output],
984 case IIO_SHARED_BY_TYPE:
985 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
986 iio_direction[chan->output],
987 iio_chan_type_name_spec[chan->type],
993 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
994 iio_direction[chan->output],
995 iio_chan_type_name_spec[chan->type],
999 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
1000 iio_direction[chan->output],
1001 iio_chan_type_name_spec[chan->type],
1008 goto error_free_full_postfix;
1010 dev_attr->attr.name = name;
1013 dev_attr->attr.mode |= S_IRUGO;
1014 dev_attr->show = readfunc;
1018 dev_attr->attr.mode |= S_IWUSR;
1019 dev_attr->store = writefunc;
1022 error_free_full_postfix:
1023 kfree(full_postfix);
1028 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
1030 kfree(dev_attr->attr.name);
1033 int __iio_add_chan_devattr(const char *postfix,
1034 struct iio_chan_spec const *chan,
1035 ssize_t (*readfunc)(struct device *dev,
1036 struct device_attribute *attr,
1038 ssize_t (*writefunc)(struct device *dev,
1039 struct device_attribute *attr,
1043 enum iio_shared_by shared_by,
1045 struct list_head *attr_list)
1048 struct iio_dev_attr *iio_attr, *t;
1050 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
1051 if (iio_attr == NULL)
1053 ret = __iio_device_attr_init(&iio_attr->dev_attr,
1055 readfunc, writefunc, shared_by);
1057 goto error_iio_dev_attr_free;
1059 iio_attr->address = mask;
1060 list_for_each_entry(t, attr_list, l)
1061 if (strcmp(t->dev_attr.attr.name,
1062 iio_attr->dev_attr.attr.name) == 0) {
1063 if (shared_by == IIO_SEPARATE)
1064 dev_err(dev, "tried to double register : %s\n",
1065 t->dev_attr.attr.name);
1067 goto error_device_attr_deinit;
1069 list_add(&iio_attr->l, attr_list);
1073 error_device_attr_deinit:
1074 __iio_device_attr_deinit(&iio_attr->dev_attr);
1075 error_iio_dev_attr_free:
1080 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
1081 struct iio_chan_spec const *chan,
1082 enum iio_shared_by shared_by,
1083 const long *infomask)
1085 int i, ret, attrcount = 0;
1087 for_each_set_bit(i, infomask, sizeof(*infomask)*8) {
1088 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
1090 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
1092 &iio_read_channel_info,
1093 &iio_write_channel_info,
1097 &indio_dev->channel_attr_list);
1098 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1108 static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,
1109 struct iio_chan_spec const *chan,
1110 enum iio_shared_by shared_by,
1111 const long *infomask)
1113 int i, ret, attrcount = 0;
1114 char *avail_postfix;
1116 for_each_set_bit(i, infomask, sizeof(*infomask) * 8) {
1117 avail_postfix = kasprintf(GFP_KERNEL,
1119 iio_chan_info_postfix[i]);
1123 ret = __iio_add_chan_devattr(avail_postfix,
1125 &iio_read_channel_info_avail,
1130 &indio_dev->channel_attr_list);
1131 kfree(avail_postfix);
1132 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
1142 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
1143 struct iio_chan_spec const *chan)
1145 int ret, attrcount = 0;
1146 const struct iio_chan_spec_ext_info *ext_info;
1148 if (chan->channel < 0)
1150 ret = iio_device_add_info_mask_type(indio_dev, chan,
1152 &chan->info_mask_separate);
1157 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1160 info_mask_separate_available);
1165 ret = iio_device_add_info_mask_type(indio_dev, chan,
1167 &chan->info_mask_shared_by_type);
1172 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1175 info_mask_shared_by_type_available);
1180 ret = iio_device_add_info_mask_type(indio_dev, chan,
1182 &chan->info_mask_shared_by_dir);
1187 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1189 &chan->info_mask_shared_by_dir_available);
1194 ret = iio_device_add_info_mask_type(indio_dev, chan,
1196 &chan->info_mask_shared_by_all);
1201 ret = iio_device_add_info_mask_type_avail(indio_dev, chan,
1203 &chan->info_mask_shared_by_all_available);
1208 if (chan->ext_info) {
1210 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
1211 ret = __iio_add_chan_devattr(ext_info->name,
1214 &iio_read_channel_ext_info : NULL,
1216 &iio_write_channel_ext_info : NULL,
1220 &indio_dev->channel_attr_list);
1222 if (ret == -EBUSY && ext_info->shared)
1236 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
1237 * @attr_list: List of IIO device attributes
1239 * This function frees the memory allocated for each of the IIO device
1240 * attributes in the list.
1242 void iio_free_chan_devattr_list(struct list_head *attr_list)
1244 struct iio_dev_attr *p, *n;
1246 list_for_each_entry_safe(p, n, attr_list, l) {
1247 kfree(p->dev_attr.attr.name);
1253 static ssize_t iio_show_dev_name(struct device *dev,
1254 struct device_attribute *attr,
1257 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1258 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
1261 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
1263 static ssize_t iio_show_timestamp_clock(struct device *dev,
1264 struct device_attribute *attr,
1267 const struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1268 const clockid_t clk = iio_device_get_clock(indio_dev);
1273 case CLOCK_REALTIME:
1274 name = "realtime\n";
1275 sz = sizeof("realtime\n");
1277 case CLOCK_MONOTONIC:
1278 name = "monotonic\n";
1279 sz = sizeof("monotonic\n");
1281 case CLOCK_MONOTONIC_RAW:
1282 name = "monotonic_raw\n";
1283 sz = sizeof("monotonic_raw\n");
1285 case CLOCK_REALTIME_COARSE:
1286 name = "realtime_coarse\n";
1287 sz = sizeof("realtime_coarse\n");
1289 case CLOCK_MONOTONIC_COARSE:
1290 name = "monotonic_coarse\n";
1291 sz = sizeof("monotonic_coarse\n");
1293 case CLOCK_BOOTTIME:
1294 name = "boottime\n";
1295 sz = sizeof("boottime\n");
1299 sz = sizeof("tai\n");
1305 memcpy(buf, name, sz);
1309 static ssize_t iio_store_timestamp_clock(struct device *dev,
1310 struct device_attribute *attr,
1311 const char *buf, size_t len)
1316 if (sysfs_streq(buf, "realtime"))
1317 clk = CLOCK_REALTIME;
1318 else if (sysfs_streq(buf, "monotonic"))
1319 clk = CLOCK_MONOTONIC;
1320 else if (sysfs_streq(buf, "monotonic_raw"))
1321 clk = CLOCK_MONOTONIC_RAW;
1322 else if (sysfs_streq(buf, "realtime_coarse"))
1323 clk = CLOCK_REALTIME_COARSE;
1324 else if (sysfs_streq(buf, "monotonic_coarse"))
1325 clk = CLOCK_MONOTONIC_COARSE;
1326 else if (sysfs_streq(buf, "boottime"))
1327 clk = CLOCK_BOOTTIME;
1328 else if (sysfs_streq(buf, "tai"))
1333 ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);
1340 static DEVICE_ATTR(current_timestamp_clock, S_IRUGO | S_IWUSR,
1341 iio_show_timestamp_clock, iio_store_timestamp_clock);
1343 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
1345 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
1346 struct iio_dev_attr *p;
1347 struct attribute **attr, *clk = NULL;
1349 /* First count elements in any existing group */
1350 if (indio_dev->info->attrs) {
1351 attr = indio_dev->info->attrs->attrs;
1352 while (*attr++ != NULL)
1355 attrcount = attrcount_orig;
1357 * New channel registration method - relies on the fact a group does
1358 * not need to be initialized if its name is NULL.
1360 if (indio_dev->channels)
1361 for (i = 0; i < indio_dev->num_channels; i++) {
1362 const struct iio_chan_spec *chan =
1363 &indio_dev->channels[i];
1365 if (chan->type == IIO_TIMESTAMP)
1366 clk = &dev_attr_current_timestamp_clock.attr;
1368 ret = iio_device_add_channel_sysfs(indio_dev, chan);
1370 goto error_clear_attrs;
1374 if (indio_dev->event_interface)
1375 clk = &dev_attr_current_timestamp_clock.attr;
1377 if (indio_dev->name)
1382 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
1383 sizeof(indio_dev->chan_attr_group.attrs[0]),
1385 if (indio_dev->chan_attr_group.attrs == NULL) {
1387 goto error_clear_attrs;
1389 /* Copy across original attributes */
1390 if (indio_dev->info->attrs)
1391 memcpy(indio_dev->chan_attr_group.attrs,
1392 indio_dev->info->attrs->attrs,
1393 sizeof(indio_dev->chan_attr_group.attrs[0])
1395 attrn = attrcount_orig;
1396 /* Add all elements from the list. */
1397 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
1398 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
1399 if (indio_dev->name)
1400 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
1402 indio_dev->chan_attr_group.attrs[attrn++] = clk;
1404 indio_dev->groups[indio_dev->groupcounter++] =
1405 &indio_dev->chan_attr_group;
1410 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1415 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
1418 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1419 kfree(indio_dev->chan_attr_group.attrs);
1420 indio_dev->chan_attr_group.attrs = NULL;
1423 static void iio_dev_release(struct device *device)
1425 struct iio_dev *indio_dev = dev_to_iio_dev(device);
1426 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1427 iio_device_unregister_trigger_consumer(indio_dev);
1428 iio_device_unregister_eventset(indio_dev);
1429 iio_device_unregister_sysfs(indio_dev);
1431 iio_buffer_put(indio_dev->buffer);
1433 ida_simple_remove(&iio_ida, indio_dev->id);
1437 struct device_type iio_device_type = {
1438 .name = "iio_device",
1439 .release = iio_dev_release,
1443 * iio_device_alloc() - allocate an iio_dev from a driver
1444 * @sizeof_priv: Space to allocate for private structure.
1446 struct iio_dev *iio_device_alloc(int sizeof_priv)
1448 struct iio_dev *dev;
1451 alloc_size = sizeof(struct iio_dev);
1453 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1454 alloc_size += sizeof_priv;
1456 /* ensure 32-byte alignment of whole construct ? */
1457 alloc_size += IIO_ALIGN - 1;
1459 dev = kzalloc(alloc_size, GFP_KERNEL);
1462 dev->dev.groups = dev->groups;
1463 dev->dev.type = &iio_device_type;
1464 dev->dev.bus = &iio_bus_type;
1465 device_initialize(&dev->dev);
1466 dev_set_drvdata(&dev->dev, (void *)dev);
1467 mutex_init(&dev->mlock);
1468 mutex_init(&dev->info_exist_lock);
1469 INIT_LIST_HEAD(&dev->channel_attr_list);
1471 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1473 /* cannot use a dev_err as the name isn't available */
1474 pr_err("failed to get device id\n");
1478 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1479 INIT_LIST_HEAD(&dev->buffer_list);
1484 EXPORT_SYMBOL(iio_device_alloc);
1487 * iio_device_free() - free an iio_dev from a driver
1488 * @dev: the iio_dev associated with the device
1490 void iio_device_free(struct iio_dev *dev)
1493 put_device(&dev->dev);
1495 EXPORT_SYMBOL(iio_device_free);
1497 static void devm_iio_device_release(struct device *dev, void *res)
1499 iio_device_free(*(struct iio_dev **)res);
1502 int devm_iio_device_match(struct device *dev, void *res, void *data)
1504 struct iio_dev **r = res;
1511 EXPORT_SYMBOL_GPL(devm_iio_device_match);
1514 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1515 * @dev: Device to allocate iio_dev for
1516 * @sizeof_priv: Space to allocate for private structure.
1518 * Managed iio_device_alloc. iio_dev allocated with this function is
1519 * automatically freed on driver detach.
1521 * If an iio_dev allocated with this function needs to be freed separately,
1522 * devm_iio_device_free() must be used.
1525 * Pointer to allocated iio_dev on success, NULL on failure.
1527 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1529 struct iio_dev **ptr, *iio_dev;
1531 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1536 iio_dev = iio_device_alloc(sizeof_priv);
1539 devres_add(dev, ptr);
1546 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1549 * devm_iio_device_free - Resource-managed iio_device_free()
1550 * @dev: Device this iio_dev belongs to
1551 * @iio_dev: the iio_dev associated with the device
1553 * Free iio_dev allocated with devm_iio_device_alloc().
1555 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1559 rc = devres_release(dev, devm_iio_device_release,
1560 devm_iio_device_match, iio_dev);
1563 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1566 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1567 * @inode: Inode structure for identifying the device in the file system
1568 * @filp: File structure for iio device used to keep and later access
1571 * Return: 0 on success or -EBUSY if the device is already opened
1573 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1575 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1576 struct iio_dev, chrdev);
1578 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1581 iio_device_get(indio_dev);
1583 filp->private_data = indio_dev;
1589 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1590 * @inode: Inode structure pointer for the char device
1591 * @filp: File structure pointer for the char device
1593 * Return: 0 for successful release
1595 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1597 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1598 struct iio_dev, chrdev);
1599 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1600 iio_device_put(indio_dev);
1605 /* Somewhat of a cross file organization violation - ioctls here are actually
1607 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1609 struct iio_dev *indio_dev = filp->private_data;
1610 int __user *ip = (int __user *)arg;
1613 if (!indio_dev->info)
1616 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1617 fd = iio_event_getfd(indio_dev);
1620 if (copy_to_user(ip, &fd, sizeof(fd)))
1627 static const struct file_operations iio_buffer_fileops = {
1628 .read = iio_buffer_read_first_n_outer_addr,
1629 .release = iio_chrdev_release,
1630 .open = iio_chrdev_open,
1631 .poll = iio_buffer_poll_addr,
1632 .owner = THIS_MODULE,
1633 .llseek = noop_llseek,
1634 .unlocked_ioctl = iio_ioctl,
1635 .compat_ioctl = iio_ioctl,
1638 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1641 const struct iio_chan_spec *channels = indio_dev->channels;
1643 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1646 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1647 if (channels[i].scan_index < 0)
1649 for (j = i + 1; j < indio_dev->num_channels; j++)
1650 if (channels[i].scan_index == channels[j].scan_index) {
1651 dev_err(&indio_dev->dev,
1652 "Duplicate scan index %d\n",
1653 channels[i].scan_index);
1661 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1664 * iio_device_register() - register a device with the IIO subsystem
1665 * @indio_dev: Device structure filled by the device driver
1667 int iio_device_register(struct iio_dev *indio_dev)
1671 /* If the calling driver did not initialize of_node, do it here */
1672 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1673 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1675 ret = iio_check_unique_scan_index(indio_dev);
1679 /* configure elements for the chrdev */
1680 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1682 ret = iio_device_register_debugfs(indio_dev);
1684 dev_err(indio_dev->dev.parent,
1685 "Failed to register debugfs interfaces\n");
1689 ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1691 dev_err(indio_dev->dev.parent,
1692 "Failed to create buffer sysfs interfaces\n");
1693 goto error_unreg_debugfs;
1696 ret = iio_device_register_sysfs(indio_dev);
1698 dev_err(indio_dev->dev.parent,
1699 "Failed to register sysfs interfaces\n");
1700 goto error_buffer_free_sysfs;
1702 ret = iio_device_register_eventset(indio_dev);
1704 dev_err(indio_dev->dev.parent,
1705 "Failed to register event set\n");
1706 goto error_free_sysfs;
1708 if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)
1709 iio_device_register_trigger_consumer(indio_dev);
1711 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1712 indio_dev->setup_ops == NULL)
1713 indio_dev->setup_ops = &noop_ring_setup_ops;
1715 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1716 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1718 ret = cdev_device_add(&indio_dev->chrdev, &indio_dev->dev);
1720 goto error_unreg_eventset;
1724 error_unreg_eventset:
1725 iio_device_unregister_eventset(indio_dev);
1727 iio_device_unregister_sysfs(indio_dev);
1728 error_buffer_free_sysfs:
1729 iio_buffer_free_sysfs_and_mask(indio_dev);
1730 error_unreg_debugfs:
1731 iio_device_unregister_debugfs(indio_dev);
1734 EXPORT_SYMBOL(iio_device_register);
1737 * iio_device_unregister() - unregister a device from the IIO subsystem
1738 * @indio_dev: Device structure representing the device.
1740 void iio_device_unregister(struct iio_dev *indio_dev)
1742 mutex_lock(&indio_dev->info_exist_lock);
1744 cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
1746 iio_device_unregister_debugfs(indio_dev);
1748 iio_disable_all_buffers(indio_dev);
1750 indio_dev->info = NULL;
1752 iio_device_wakeup_eventset(indio_dev);
1753 iio_buffer_wakeup_poll(indio_dev);
1755 mutex_unlock(&indio_dev->info_exist_lock);
1757 iio_buffer_free_sysfs_and_mask(indio_dev);
1759 EXPORT_SYMBOL(iio_device_unregister);
1761 static void devm_iio_device_unreg(struct device *dev, void *res)
1763 iio_device_unregister(*(struct iio_dev **)res);
1767 * devm_iio_device_register - Resource-managed iio_device_register()
1768 * @dev: Device to allocate iio_dev for
1769 * @indio_dev: Device structure filled by the device driver
1771 * Managed iio_device_register. The IIO device registered with this
1772 * function is automatically unregistered on driver detach. This function
1773 * calls iio_device_register() internally. Refer to that function for more
1776 * If an iio_dev registered with this function needs to be unregistered
1777 * separately, devm_iio_device_unregister() must be used.
1780 * 0 on success, negative error number on failure.
1782 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev)
1784 struct iio_dev **ptr;
1787 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1792 ret = iio_device_register(indio_dev);
1794 devres_add(dev, ptr);
1800 EXPORT_SYMBOL_GPL(devm_iio_device_register);
1803 * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1804 * @dev: Device this iio_dev belongs to
1805 * @indio_dev: the iio_dev associated with the device
1807 * Unregister iio_dev registered with devm_iio_device_register().
1809 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1813 rc = devres_release(dev, devm_iio_device_unreg,
1814 devm_iio_device_match, indio_dev);
1817 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1820 * iio_device_claim_direct_mode - Keep device in direct mode
1821 * @indio_dev: the iio_dev associated with the device
1823 * If the device is in direct mode it is guaranteed to stay
1824 * that way until iio_device_release_direct_mode() is called.
1826 * Use with iio_device_release_direct_mode()
1828 * Returns: 0 on success, -EBUSY on failure
1830 int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
1832 mutex_lock(&indio_dev->mlock);
1834 if (iio_buffer_enabled(indio_dev)) {
1835 mutex_unlock(&indio_dev->mlock);
1840 EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
1843 * iio_device_release_direct_mode - releases claim on direct mode
1844 * @indio_dev: the iio_dev associated with the device
1846 * Release the claim. Device is no longer guaranteed to stay
1849 * Use with iio_device_claim_direct_mode()
1851 void iio_device_release_direct_mode(struct iio_dev *indio_dev)
1853 mutex_unlock(&indio_dev->mlock);
1855 EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
1857 subsys_initcall(iio_init);
1858 module_exit(iio_exit);
1860 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1861 MODULE_DESCRIPTION("Industrial I/O core");
1862 MODULE_LICENSE("GPL");