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>
36 /* IDA to assign each registered device a unique id */
37 static DEFINE_IDA(iio_ida);
39 static dev_t iio_devt;
41 #define IIO_DEV_MAX 256
42 struct bus_type iio_bus_type = {
45 EXPORT_SYMBOL(iio_bus_type);
47 static struct dentry *iio_debugfs_dentry;
49 static const char * const iio_direction[] = {
54 static const char * const iio_chan_type_name_spec[] = {
55 [IIO_VOLTAGE] = "voltage",
56 [IIO_CURRENT] = "current",
57 [IIO_POWER] = "power",
58 [IIO_ACCEL] = "accel",
59 [IIO_ANGL_VEL] = "anglvel",
61 [IIO_LIGHT] = "illuminance",
62 [IIO_INTENSITY] = "intensity",
63 [IIO_PROXIMITY] = "proximity",
65 [IIO_INCLI] = "incli",
68 [IIO_TIMESTAMP] = "timestamp",
69 [IIO_CAPACITANCE] = "capacitance",
70 [IIO_ALTVOLTAGE] = "altvoltage",
72 [IIO_PRESSURE] = "pressure",
73 [IIO_HUMIDITYRELATIVE] = "humidityrelative",
74 [IIO_ACTIVITY] = "activity",
75 [IIO_STEPS] = "steps",
76 [IIO_ENERGY] = "energy",
77 [IIO_DISTANCE] = "distance",
78 [IIO_VELOCITY] = "velocity",
79 [IIO_CONCENTRATION] = "concentration",
80 [IIO_RESISTANCE] = "resistance",
82 [IIO_UVINDEX] = "uvindex",
85 static const char * const iio_modifier_names[] = {
89 [IIO_MOD_X_AND_Y] = "x&y",
90 [IIO_MOD_X_AND_Z] = "x&z",
91 [IIO_MOD_Y_AND_Z] = "y&z",
92 [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
93 [IIO_MOD_X_OR_Y] = "x|y",
94 [IIO_MOD_X_OR_Z] = "x|z",
95 [IIO_MOD_Y_OR_Z] = "y|z",
96 [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
97 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
98 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
99 [IIO_MOD_LIGHT_BOTH] = "both",
100 [IIO_MOD_LIGHT_IR] = "ir",
101 [IIO_MOD_LIGHT_CLEAR] = "clear",
102 [IIO_MOD_LIGHT_RED] = "red",
103 [IIO_MOD_LIGHT_GREEN] = "green",
104 [IIO_MOD_LIGHT_BLUE] = "blue",
105 [IIO_MOD_LIGHT_UV] = "uv",
106 [IIO_MOD_QUATERNION] = "quaternion",
107 [IIO_MOD_TEMP_AMBIENT] = "ambient",
108 [IIO_MOD_TEMP_OBJECT] = "object",
109 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
110 [IIO_MOD_NORTH_TRUE] = "from_north_true",
111 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
112 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
113 [IIO_MOD_RUNNING] = "running",
114 [IIO_MOD_JOGGING] = "jogging",
115 [IIO_MOD_WALKING] = "walking",
116 [IIO_MOD_STILL] = "still",
117 [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
120 [IIO_MOD_CO2] = "co2",
121 [IIO_MOD_VOC] = "voc",
124 /* relies on pairs of these shared then separate */
125 static const char * const iio_chan_info_postfix[] = {
126 [IIO_CHAN_INFO_RAW] = "raw",
127 [IIO_CHAN_INFO_PROCESSED] = "input",
128 [IIO_CHAN_INFO_SCALE] = "scale",
129 [IIO_CHAN_INFO_OFFSET] = "offset",
130 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
131 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
132 [IIO_CHAN_INFO_PEAK] = "peak_raw",
133 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
134 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
135 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
136 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
137 = "filter_low_pass_3db_frequency",
138 [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
139 = "filter_high_pass_3db_frequency",
140 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
141 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
142 [IIO_CHAN_INFO_PHASE] = "phase",
143 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
144 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
145 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
146 [IIO_CHAN_INFO_ENABLE] = "en",
147 [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
148 [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
149 [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
150 [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
151 [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
152 [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
156 * iio_find_channel_from_si() - get channel from its scan index
158 * @si: scan index to match
160 const struct iio_chan_spec
161 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
165 for (i = 0; i < indio_dev->num_channels; i++)
166 if (indio_dev->channels[i].scan_index == si)
167 return &indio_dev->channels[i];
171 /* This turns up an awful lot */
172 ssize_t iio_read_const_attr(struct device *dev,
173 struct device_attribute *attr,
176 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
178 EXPORT_SYMBOL(iio_read_const_attr);
180 static int __init iio_init(void)
184 /* Register sysfs bus */
185 ret = bus_register(&iio_bus_type);
187 pr_err("could not register bus type\n");
191 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
193 pr_err("failed to allocate char dev region\n");
194 goto error_unregister_bus_type;
197 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
201 error_unregister_bus_type:
202 bus_unregister(&iio_bus_type);
207 static void __exit iio_exit(void)
210 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
211 bus_unregister(&iio_bus_type);
212 debugfs_remove(iio_debugfs_dentry);
215 #if defined(CONFIG_DEBUG_FS)
216 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
217 size_t count, loff_t *ppos)
219 struct iio_dev *indio_dev = file->private_data;
225 ret = indio_dev->info->debugfs_reg_access(indio_dev,
226 indio_dev->cached_reg_addr,
229 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
231 len = snprintf(buf, sizeof(buf), "0x%X\n", val);
233 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
236 static ssize_t iio_debugfs_write_reg(struct file *file,
237 const char __user *userbuf, size_t count, loff_t *ppos)
239 struct iio_dev *indio_dev = file->private_data;
244 count = min_t(size_t, count, (sizeof(buf)-1));
245 if (copy_from_user(buf, userbuf, count))
250 ret = sscanf(buf, "%i %i", ®, &val);
254 indio_dev->cached_reg_addr = reg;
257 indio_dev->cached_reg_addr = reg;
258 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
261 dev_err(indio_dev->dev.parent, "%s: write failed\n",
273 static const struct file_operations iio_debugfs_reg_fops = {
275 .read = iio_debugfs_read_reg,
276 .write = iio_debugfs_write_reg,
279 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
281 debugfs_remove_recursive(indio_dev->debugfs_dentry);
284 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
288 if (indio_dev->info->debugfs_reg_access == NULL)
291 if (!iio_debugfs_dentry)
294 indio_dev->debugfs_dentry =
295 debugfs_create_dir(dev_name(&indio_dev->dev),
297 if (indio_dev->debugfs_dentry == NULL) {
298 dev_warn(indio_dev->dev.parent,
299 "Failed to create debugfs directory\n");
303 d = debugfs_create_file("direct_reg_access", 0644,
304 indio_dev->debugfs_dentry,
305 indio_dev, &iio_debugfs_reg_fops);
307 iio_device_unregister_debugfs(indio_dev);
314 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
319 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
322 #endif /* CONFIG_DEBUG_FS */
324 static ssize_t iio_read_channel_ext_info(struct device *dev,
325 struct device_attribute *attr,
328 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
329 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
330 const struct iio_chan_spec_ext_info *ext_info;
332 ext_info = &this_attr->c->ext_info[this_attr->address];
334 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
337 static ssize_t iio_write_channel_ext_info(struct device *dev,
338 struct device_attribute *attr,
342 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
343 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
344 const struct iio_chan_spec_ext_info *ext_info;
346 ext_info = &this_attr->c->ext_info[this_attr->address];
348 return ext_info->write(indio_dev, ext_info->private,
349 this_attr->c, buf, len);
352 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
353 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
355 const struct iio_enum *e = (const struct iio_enum *)priv;
362 for (i = 0; i < e->num_items; ++i)
363 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
365 /* replace last space with a newline */
370 EXPORT_SYMBOL_GPL(iio_enum_available_read);
372 ssize_t iio_enum_read(struct iio_dev *indio_dev,
373 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
375 const struct iio_enum *e = (const struct iio_enum *)priv;
381 i = e->get(indio_dev, chan);
384 else if (i >= e->num_items)
387 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
389 EXPORT_SYMBOL_GPL(iio_enum_read);
391 ssize_t iio_enum_write(struct iio_dev *indio_dev,
392 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
395 const struct iio_enum *e = (const struct iio_enum *)priv;
402 for (i = 0; i < e->num_items; i++) {
403 if (sysfs_streq(buf, e->items[i]))
407 if (i == e->num_items)
410 ret = e->set(indio_dev, chan, i);
411 return ret ? ret : len;
413 EXPORT_SYMBOL_GPL(iio_enum_write);
415 static const struct iio_mount_matrix iio_mount_idmatrix = {
423 static int iio_setup_mount_idmatrix(const struct device *dev,
424 struct iio_mount_matrix *matrix)
426 *matrix = iio_mount_idmatrix;
427 dev_info(dev, "mounting matrix not found: using identity...\n");
431 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
432 const struct iio_chan_spec *chan, char *buf)
434 const struct iio_mount_matrix *mtx = ((iio_get_mount_matrix_t *)
435 priv)(indio_dev, chan);
441 mtx = &iio_mount_idmatrix;
443 return snprintf(buf, PAGE_SIZE, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",
444 mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],
445 mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],
446 mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);
448 EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
451 * of_iio_read_mount_matrix() - retrieve iio device mounting matrix from
452 * device-tree "mount-matrix" property
453 * @dev: device the mounting matrix property is assigned to
454 * @propname: device specific mounting matrix property name
455 * @matrix: where to store retrieved matrix
457 * If device is assigned no mounting matrix property, a default 3x3 identity
458 * matrix will be filled in.
460 * Return: 0 if success, or a negative error code on failure.
463 int of_iio_read_mount_matrix(const struct device *dev,
464 const char *propname,
465 struct iio_mount_matrix *matrix)
468 int err = of_property_read_string_array(dev->of_node,
469 propname, matrix->rotation,
470 ARRAY_SIZE(iio_mount_idmatrix.rotation));
472 if (err == ARRAY_SIZE(iio_mount_idmatrix.rotation))
476 /* Invalid number of matrix entries. */
480 /* Invalid matrix declaration format. */
484 /* Matrix was not declared at all: fallback to identity. */
485 return iio_setup_mount_idmatrix(dev, matrix);
488 int of_iio_read_mount_matrix(const struct device *dev,
489 const char *propname,
490 struct iio_mount_matrix *matrix)
492 return iio_setup_mount_idmatrix(dev, matrix);
495 EXPORT_SYMBOL(of_iio_read_mount_matrix);
498 * iio_format_value() - Formats a IIO value into its string representation
499 * @buf: The buffer to which the formatted value gets written
500 * @type: One of the IIO_VAL_... constants. This decides how the val
501 * and val2 parameters are formatted.
502 * @size: Number of IIO value entries contained in vals
503 * @vals: Pointer to the values, exact meaning depends on the
506 * Return: 0 by default, a negative number on failure or the
507 * total number of characters written for a type that belongs
508 * to the IIO_VAL_... constant.
510 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
512 unsigned long long tmp;
513 bool scale_db = false;
517 return sprintf(buf, "%d\n", vals[0]);
518 case IIO_VAL_INT_PLUS_MICRO_DB:
520 case IIO_VAL_INT_PLUS_MICRO:
522 return sprintf(buf, "-%d.%06u%s\n", abs(vals[0]),
523 -vals[1], scale_db ? " dB" : "");
525 return sprintf(buf, "%d.%06u%s\n", vals[0], vals[1],
526 scale_db ? " dB" : "");
527 case IIO_VAL_INT_PLUS_NANO:
529 return sprintf(buf, "-%d.%09u\n", abs(vals[0]),
532 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
533 case IIO_VAL_FRACTIONAL:
534 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
535 vals[1] = do_div(tmp, 1000000000LL);
537 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
538 case IIO_VAL_FRACTIONAL_LOG2:
539 tmp = (s64)vals[0] * 1000000000LL >> vals[1];
540 vals[1] = do_div(tmp, 1000000000LL);
542 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
543 case IIO_VAL_INT_MULTIPLE:
548 for (i = 0; i < size; ++i)
549 len += snprintf(&buf[len], PAGE_SIZE - len, "%d ",
551 len += snprintf(&buf[len], PAGE_SIZE - len, "\n");
558 EXPORT_SYMBOL_GPL(iio_format_value);
560 static ssize_t iio_read_channel_info(struct device *dev,
561 struct device_attribute *attr,
564 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
565 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
566 int vals[INDIO_MAX_RAW_ELEMENTS];
570 if (indio_dev->info->read_raw_multi)
571 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
572 INDIO_MAX_RAW_ELEMENTS,
576 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
577 &vals[0], &vals[1], this_attr->address);
582 return iio_format_value(buf, ret, val_len, vals);
586 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
587 * @str: The string to parse
588 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
589 * @integer: The integer part of the number
590 * @fract: The fractional part of the number
592 * Returns 0 on success, or a negative error code if the string could not be
595 int iio_str_to_fixpoint(const char *str, int fract_mult,
596 int *integer, int *fract)
599 bool integer_part = true, negative = false;
601 if (fract_mult == 0) {
604 return kstrtoint(str, 0, integer);
610 } else if (str[0] == '+') {
615 if ('0' <= *str && *str <= '9') {
617 i = i * 10 + *str - '0';
619 f += fract_mult * (*str - '0');
622 } else if (*str == '\n') {
623 if (*(str + 1) == '\0')
627 } else if (*str == '.' && integer_part) {
628 integer_part = false;
647 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
649 static ssize_t iio_write_channel_info(struct device *dev,
650 struct device_attribute *attr,
654 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
655 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
656 int ret, fract_mult = 100000;
659 /* Assumes decimal - precision based on number of digits */
660 if (!indio_dev->info->write_raw)
663 if (indio_dev->info->write_raw_get_fmt)
664 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
665 this_attr->c, this_attr->address)) {
669 case IIO_VAL_INT_PLUS_MICRO:
672 case IIO_VAL_INT_PLUS_NANO:
673 fract_mult = 100000000;
679 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
683 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
684 integer, fract, this_attr->address);
692 int __iio_device_attr_init(struct device_attribute *dev_attr,
694 struct iio_chan_spec const *chan,
695 ssize_t (*readfunc)(struct device *dev,
696 struct device_attribute *attr,
698 ssize_t (*writefunc)(struct device *dev,
699 struct device_attribute *attr,
702 enum iio_shared_by shared_by)
707 sysfs_attr_init(&dev_attr->attr);
709 /* Build up postfix of <extend_name>_<modifier>_postfix */
710 if (chan->modified && (shared_by == IIO_SEPARATE)) {
711 if (chan->extend_name)
712 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
713 iio_modifier_names[chan
718 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
719 iio_modifier_names[chan
723 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
724 full_postfix = kstrdup(postfix, GFP_KERNEL);
726 full_postfix = kasprintf(GFP_KERNEL,
731 if (full_postfix == NULL)
734 if (chan->differential) { /* Differential can not have modifier */
736 case IIO_SHARED_BY_ALL:
737 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
739 case IIO_SHARED_BY_DIR:
740 name = kasprintf(GFP_KERNEL, "%s_%s",
741 iio_direction[chan->output],
744 case IIO_SHARED_BY_TYPE:
745 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
746 iio_direction[chan->output],
747 iio_chan_type_name_spec[chan->type],
748 iio_chan_type_name_spec[chan->type],
752 if (!chan->indexed) {
753 WARN(1, "Differential channels must be indexed\n");
755 goto error_free_full_postfix;
757 name = kasprintf(GFP_KERNEL,
759 iio_direction[chan->output],
760 iio_chan_type_name_spec[chan->type],
762 iio_chan_type_name_spec[chan->type],
767 } else { /* Single ended */
769 case IIO_SHARED_BY_ALL:
770 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
772 case IIO_SHARED_BY_DIR:
773 name = kasprintf(GFP_KERNEL, "%s_%s",
774 iio_direction[chan->output],
777 case IIO_SHARED_BY_TYPE:
778 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
779 iio_direction[chan->output],
780 iio_chan_type_name_spec[chan->type],
786 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
787 iio_direction[chan->output],
788 iio_chan_type_name_spec[chan->type],
792 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
793 iio_direction[chan->output],
794 iio_chan_type_name_spec[chan->type],
801 goto error_free_full_postfix;
803 dev_attr->attr.name = name;
806 dev_attr->attr.mode |= S_IRUGO;
807 dev_attr->show = readfunc;
811 dev_attr->attr.mode |= S_IWUSR;
812 dev_attr->store = writefunc;
815 error_free_full_postfix:
821 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
823 kfree(dev_attr->attr.name);
826 int __iio_add_chan_devattr(const char *postfix,
827 struct iio_chan_spec const *chan,
828 ssize_t (*readfunc)(struct device *dev,
829 struct device_attribute *attr,
831 ssize_t (*writefunc)(struct device *dev,
832 struct device_attribute *attr,
836 enum iio_shared_by shared_by,
838 struct list_head *attr_list)
841 struct iio_dev_attr *iio_attr, *t;
843 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
844 if (iio_attr == NULL)
846 ret = __iio_device_attr_init(&iio_attr->dev_attr,
848 readfunc, writefunc, shared_by);
850 goto error_iio_dev_attr_free;
852 iio_attr->address = mask;
853 list_for_each_entry(t, attr_list, l)
854 if (strcmp(t->dev_attr.attr.name,
855 iio_attr->dev_attr.attr.name) == 0) {
856 if (shared_by == IIO_SEPARATE)
857 dev_err(dev, "tried to double register : %s\n",
858 t->dev_attr.attr.name);
860 goto error_device_attr_deinit;
862 list_add(&iio_attr->l, attr_list);
866 error_device_attr_deinit:
867 __iio_device_attr_deinit(&iio_attr->dev_attr);
868 error_iio_dev_attr_free:
873 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
874 struct iio_chan_spec const *chan,
875 enum iio_shared_by shared_by,
876 const long *infomask)
878 int i, ret, attrcount = 0;
880 for_each_set_bit(i, infomask, sizeof(infomask)*8) {
881 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
883 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
885 &iio_read_channel_info,
886 &iio_write_channel_info,
890 &indio_dev->channel_attr_list);
891 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
901 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
902 struct iio_chan_spec const *chan)
904 int ret, attrcount = 0;
905 const struct iio_chan_spec_ext_info *ext_info;
907 if (chan->channel < 0)
909 ret = iio_device_add_info_mask_type(indio_dev, chan,
911 &chan->info_mask_separate);
916 ret = iio_device_add_info_mask_type(indio_dev, chan,
918 &chan->info_mask_shared_by_type);
923 ret = iio_device_add_info_mask_type(indio_dev, chan,
925 &chan->info_mask_shared_by_dir);
930 ret = iio_device_add_info_mask_type(indio_dev, chan,
932 &chan->info_mask_shared_by_all);
937 if (chan->ext_info) {
939 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
940 ret = __iio_add_chan_devattr(ext_info->name,
943 &iio_read_channel_ext_info : NULL,
945 &iio_write_channel_ext_info : NULL,
949 &indio_dev->channel_attr_list);
951 if (ret == -EBUSY && ext_info->shared)
965 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
966 * @attr_list: List of IIO device attributes
968 * This function frees the memory allocated for each of the IIO device
969 * attributes in the list.
971 void iio_free_chan_devattr_list(struct list_head *attr_list)
973 struct iio_dev_attr *p, *n;
975 list_for_each_entry_safe(p, n, attr_list, l) {
976 kfree(p->dev_attr.attr.name);
982 static ssize_t iio_show_dev_name(struct device *dev,
983 struct device_attribute *attr,
986 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
987 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
990 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
992 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
994 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
995 struct iio_dev_attr *p;
996 struct attribute **attr;
998 /* First count elements in any existing group */
999 if (indio_dev->info->attrs) {
1000 attr = indio_dev->info->attrs->attrs;
1001 while (*attr++ != NULL)
1004 attrcount = attrcount_orig;
1006 * New channel registration method - relies on the fact a group does
1007 * not need to be initialized if its name is NULL.
1009 if (indio_dev->channels)
1010 for (i = 0; i < indio_dev->num_channels; i++) {
1011 ret = iio_device_add_channel_sysfs(indio_dev,
1015 goto error_clear_attrs;
1019 if (indio_dev->name)
1022 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
1023 sizeof(indio_dev->chan_attr_group.attrs[0]),
1025 if (indio_dev->chan_attr_group.attrs == NULL) {
1027 goto error_clear_attrs;
1029 /* Copy across original attributes */
1030 if (indio_dev->info->attrs)
1031 memcpy(indio_dev->chan_attr_group.attrs,
1032 indio_dev->info->attrs->attrs,
1033 sizeof(indio_dev->chan_attr_group.attrs[0])
1035 attrn = attrcount_orig;
1036 /* Add all elements from the list. */
1037 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
1038 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
1039 if (indio_dev->name)
1040 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
1042 indio_dev->groups[indio_dev->groupcounter++] =
1043 &indio_dev->chan_attr_group;
1048 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1053 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
1056 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
1057 kfree(indio_dev->chan_attr_group.attrs);
1058 indio_dev->chan_attr_group.attrs = NULL;
1061 static void iio_dev_release(struct device *device)
1063 struct iio_dev *indio_dev = dev_to_iio_dev(device);
1064 if (indio_dev->modes & (INDIO_BUFFER_TRIGGERED | INDIO_EVENT_TRIGGERED))
1065 iio_device_unregister_trigger_consumer(indio_dev);
1066 iio_device_unregister_eventset(indio_dev);
1067 iio_device_unregister_sysfs(indio_dev);
1069 iio_buffer_put(indio_dev->buffer);
1071 ida_simple_remove(&iio_ida, indio_dev->id);
1075 struct device_type iio_device_type = {
1076 .name = "iio_device",
1077 .release = iio_dev_release,
1081 * iio_device_alloc() - allocate an iio_dev from a driver
1082 * @sizeof_priv: Space to allocate for private structure.
1084 struct iio_dev *iio_device_alloc(int sizeof_priv)
1086 struct iio_dev *dev;
1089 alloc_size = sizeof(struct iio_dev);
1091 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1092 alloc_size += sizeof_priv;
1094 /* ensure 32-byte alignment of whole construct ? */
1095 alloc_size += IIO_ALIGN - 1;
1097 dev = kzalloc(alloc_size, GFP_KERNEL);
1100 dev->dev.groups = dev->groups;
1101 dev->dev.type = &iio_device_type;
1102 dev->dev.bus = &iio_bus_type;
1103 device_initialize(&dev->dev);
1104 dev_set_drvdata(&dev->dev, (void *)dev);
1105 mutex_init(&dev->mlock);
1106 mutex_init(&dev->info_exist_lock);
1107 INIT_LIST_HEAD(&dev->channel_attr_list);
1109 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1111 /* cannot use a dev_err as the name isn't available */
1112 pr_err("failed to get device id\n");
1116 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1117 INIT_LIST_HEAD(&dev->buffer_list);
1122 EXPORT_SYMBOL(iio_device_alloc);
1125 * iio_device_free() - free an iio_dev from a driver
1126 * @dev: the iio_dev associated with the device
1128 void iio_device_free(struct iio_dev *dev)
1131 put_device(&dev->dev);
1133 EXPORT_SYMBOL(iio_device_free);
1135 static void devm_iio_device_release(struct device *dev, void *res)
1137 iio_device_free(*(struct iio_dev **)res);
1140 static int devm_iio_device_match(struct device *dev, void *res, void *data)
1142 struct iio_dev **r = res;
1151 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1152 * @dev: Device to allocate iio_dev for
1153 * @sizeof_priv: Space to allocate for private structure.
1155 * Managed iio_device_alloc. iio_dev allocated with this function is
1156 * automatically freed on driver detach.
1158 * If an iio_dev allocated with this function needs to be freed separately,
1159 * devm_iio_device_free() must be used.
1162 * Pointer to allocated iio_dev on success, NULL on failure.
1164 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1166 struct iio_dev **ptr, *iio_dev;
1168 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1173 iio_dev = iio_device_alloc(sizeof_priv);
1176 devres_add(dev, ptr);
1183 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1186 * devm_iio_device_free - Resource-managed iio_device_free()
1187 * @dev: Device this iio_dev belongs to
1188 * @iio_dev: the iio_dev associated with the device
1190 * Free iio_dev allocated with devm_iio_device_alloc().
1192 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1196 rc = devres_release(dev, devm_iio_device_release,
1197 devm_iio_device_match, iio_dev);
1200 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1203 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1204 * @inode: Inode structure for identifying the device in the file system
1205 * @filp: File structure for iio device used to keep and later access
1208 * Return: 0 on success or -EBUSY if the device is already opened
1210 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1212 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1213 struct iio_dev, chrdev);
1215 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1218 iio_device_get(indio_dev);
1220 filp->private_data = indio_dev;
1226 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1227 * @inode: Inode structure pointer for the char device
1228 * @filp: File structure pointer for the char device
1230 * Return: 0 for successful release
1232 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1234 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1235 struct iio_dev, chrdev);
1236 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1237 iio_device_put(indio_dev);
1242 /* Somewhat of a cross file organization violation - ioctls here are actually
1244 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1246 struct iio_dev *indio_dev = filp->private_data;
1247 int __user *ip = (int __user *)arg;
1250 if (!indio_dev->info)
1253 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1254 fd = iio_event_getfd(indio_dev);
1257 if (copy_to_user(ip, &fd, sizeof(fd)))
1264 static const struct file_operations iio_buffer_fileops = {
1265 .read = iio_buffer_read_first_n_outer_addr,
1266 .release = iio_chrdev_release,
1267 .open = iio_chrdev_open,
1268 .poll = iio_buffer_poll_addr,
1269 .owner = THIS_MODULE,
1270 .llseek = noop_llseek,
1271 .unlocked_ioctl = iio_ioctl,
1272 .compat_ioctl = iio_ioctl,
1275 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1278 const struct iio_chan_spec *channels = indio_dev->channels;
1280 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1283 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1284 if (channels[i].scan_index < 0)
1286 for (j = i + 1; j < indio_dev->num_channels; j++)
1287 if (channels[i].scan_index == channels[j].scan_index) {
1288 dev_err(&indio_dev->dev,
1289 "Duplicate scan index %d\n",
1290 channels[i].scan_index);
1298 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1301 * iio_device_register() - register a device with the IIO subsystem
1302 * @indio_dev: Device structure filled by the device driver
1304 int iio_device_register(struct iio_dev *indio_dev)
1308 /* If the calling driver did not initialize of_node, do it here */
1309 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1310 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1312 ret = iio_check_unique_scan_index(indio_dev);
1316 /* configure elements for the chrdev */
1317 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1319 ret = iio_device_register_debugfs(indio_dev);
1321 dev_err(indio_dev->dev.parent,
1322 "Failed to register debugfs interfaces\n");
1326 ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1328 dev_err(indio_dev->dev.parent,
1329 "Failed to create buffer sysfs interfaces\n");
1330 goto error_unreg_debugfs;
1333 ret = iio_device_register_sysfs(indio_dev);
1335 dev_err(indio_dev->dev.parent,
1336 "Failed to register sysfs interfaces\n");
1337 goto error_buffer_free_sysfs;
1339 ret = iio_device_register_eventset(indio_dev);
1341 dev_err(indio_dev->dev.parent,
1342 "Failed to register event set\n");
1343 goto error_free_sysfs;
1345 if (indio_dev->modes & (INDIO_BUFFER_TRIGGERED | INDIO_EVENT_TRIGGERED))
1346 iio_device_register_trigger_consumer(indio_dev);
1348 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1349 indio_dev->setup_ops == NULL)
1350 indio_dev->setup_ops = &noop_ring_setup_ops;
1352 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1353 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1354 indio_dev->chrdev.kobj.parent = &indio_dev->dev.kobj;
1355 ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
1357 goto error_unreg_eventset;
1359 ret = device_add(&indio_dev->dev);
1361 goto error_cdev_del;
1365 cdev_del(&indio_dev->chrdev);
1366 error_unreg_eventset:
1367 iio_device_unregister_eventset(indio_dev);
1369 iio_device_unregister_sysfs(indio_dev);
1370 error_buffer_free_sysfs:
1371 iio_buffer_free_sysfs_and_mask(indio_dev);
1372 error_unreg_debugfs:
1373 iio_device_unregister_debugfs(indio_dev);
1376 EXPORT_SYMBOL(iio_device_register);
1379 * iio_device_unregister() - unregister a device from the IIO subsystem
1380 * @indio_dev: Device structure representing the device.
1382 void iio_device_unregister(struct iio_dev *indio_dev)
1384 mutex_lock(&indio_dev->info_exist_lock);
1386 device_del(&indio_dev->dev);
1388 if (indio_dev->chrdev.dev)
1389 cdev_del(&indio_dev->chrdev);
1390 iio_device_unregister_debugfs(indio_dev);
1392 iio_disable_all_buffers(indio_dev);
1394 indio_dev->info = NULL;
1396 iio_device_wakeup_eventset(indio_dev);
1397 iio_buffer_wakeup_poll(indio_dev);
1399 mutex_unlock(&indio_dev->info_exist_lock);
1401 iio_buffer_free_sysfs_and_mask(indio_dev);
1403 EXPORT_SYMBOL(iio_device_unregister);
1405 static void devm_iio_device_unreg(struct device *dev, void *res)
1407 iio_device_unregister(*(struct iio_dev **)res);
1411 * devm_iio_device_register - Resource-managed iio_device_register()
1412 * @dev: Device to allocate iio_dev for
1413 * @indio_dev: Device structure filled by the device driver
1415 * Managed iio_device_register. The IIO device registered with this
1416 * function is automatically unregistered on driver detach. This function
1417 * calls iio_device_register() internally. Refer to that function for more
1420 * If an iio_dev registered with this function needs to be unregistered
1421 * separately, devm_iio_device_unregister() must be used.
1424 * 0 on success, negative error number on failure.
1426 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev)
1428 struct iio_dev **ptr;
1431 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1436 ret = iio_device_register(indio_dev);
1438 devres_add(dev, ptr);
1444 EXPORT_SYMBOL_GPL(devm_iio_device_register);
1447 * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1448 * @dev: Device this iio_dev belongs to
1449 * @indio_dev: the iio_dev associated with the device
1451 * Unregister iio_dev registered with devm_iio_device_register().
1453 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1457 rc = devres_release(dev, devm_iio_device_unreg,
1458 devm_iio_device_match, indio_dev);
1461 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1464 * iio_device_claim_direct_mode - Keep device in direct mode
1465 * @indio_dev: the iio_dev associated with the device
1467 * If the device is in direct mode it is guaranteed to stay
1468 * that way until iio_device_release_direct_mode() is called.
1470 * Use with iio_device_release_direct_mode()
1472 * Returns: 0 on success, -EBUSY on failure
1474 int iio_device_claim_direct_mode(struct iio_dev *indio_dev)
1476 mutex_lock(&indio_dev->mlock);
1478 if (iio_buffer_enabled(indio_dev)) {
1479 mutex_unlock(&indio_dev->mlock);
1484 EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);
1487 * iio_device_release_direct_mode - releases claim on direct mode
1488 * @indio_dev: the iio_dev associated with the device
1490 * Release the claim. Device is no longer guaranteed to stay
1493 * Use with iio_device_claim_direct_mode()
1495 void iio_device_release_direct_mode(struct iio_dev *indio_dev)
1497 mutex_unlock(&indio_dev->mlock);
1499 EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
1501 subsys_initcall(iio_init);
1502 module_exit(iio_exit);
1504 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1505 MODULE_DESCRIPTION("Industrial I/O core");
1506 MODULE_LICENSE("GPL");