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/iio/iio.h>
30 #include "iio_core_trigger.h"
31 #include <linux/iio/sysfs.h>
32 #include <linux/iio/events.h>
33 #include <linux/iio/buffer.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",
80 static const char * const iio_modifier_names[] = {
84 [IIO_MOD_X_AND_Y] = "x&y",
85 [IIO_MOD_X_AND_Z] = "x&z",
86 [IIO_MOD_Y_AND_Z] = "y&z",
87 [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
88 [IIO_MOD_X_OR_Y] = "x|y",
89 [IIO_MOD_X_OR_Z] = "x|z",
90 [IIO_MOD_Y_OR_Z] = "y|z",
91 [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
92 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
93 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
94 [IIO_MOD_LIGHT_BOTH] = "both",
95 [IIO_MOD_LIGHT_IR] = "ir",
96 [IIO_MOD_LIGHT_CLEAR] = "clear",
97 [IIO_MOD_LIGHT_RED] = "red",
98 [IIO_MOD_LIGHT_GREEN] = "green",
99 [IIO_MOD_LIGHT_BLUE] = "blue",
100 [IIO_MOD_QUATERNION] = "quaternion",
101 [IIO_MOD_TEMP_AMBIENT] = "ambient",
102 [IIO_MOD_TEMP_OBJECT] = "object",
103 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
104 [IIO_MOD_NORTH_TRUE] = "from_north_true",
105 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
106 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
107 [IIO_MOD_RUNNING] = "running",
108 [IIO_MOD_JOGGING] = "jogging",
109 [IIO_MOD_WALKING] = "walking",
110 [IIO_MOD_STILL] = "still",
111 [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
116 /* relies on pairs of these shared then separate */
117 static const char * const iio_chan_info_postfix[] = {
118 [IIO_CHAN_INFO_RAW] = "raw",
119 [IIO_CHAN_INFO_PROCESSED] = "input",
120 [IIO_CHAN_INFO_SCALE] = "scale",
121 [IIO_CHAN_INFO_OFFSET] = "offset",
122 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
123 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
124 [IIO_CHAN_INFO_PEAK] = "peak_raw",
125 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
126 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
127 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
128 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
129 = "filter_low_pass_3db_frequency",
130 [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
131 = "filter_high_pass_3db_frequency",
132 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
133 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
134 [IIO_CHAN_INFO_PHASE] = "phase",
135 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
136 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
137 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
138 [IIO_CHAN_INFO_ENABLE] = "en",
139 [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
140 [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
141 [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
142 [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
143 [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
144 [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
148 * iio_find_channel_from_si() - get channel from its scan index
150 * @si: scan index to match
152 const struct iio_chan_spec
153 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
157 for (i = 0; i < indio_dev->num_channels; i++)
158 if (indio_dev->channels[i].scan_index == si)
159 return &indio_dev->channels[i];
163 /* This turns up an awful lot */
164 ssize_t iio_read_const_attr(struct device *dev,
165 struct device_attribute *attr,
168 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
170 EXPORT_SYMBOL(iio_read_const_attr);
172 static int __init iio_init(void)
176 /* Register sysfs bus */
177 ret = bus_register(&iio_bus_type);
179 pr_err("could not register bus type\n");
183 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
185 pr_err("failed to allocate char dev region\n");
186 goto error_unregister_bus_type;
189 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
193 error_unregister_bus_type:
194 bus_unregister(&iio_bus_type);
199 static void __exit iio_exit(void)
202 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
203 bus_unregister(&iio_bus_type);
204 debugfs_remove(iio_debugfs_dentry);
207 #if defined(CONFIG_DEBUG_FS)
208 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
209 size_t count, loff_t *ppos)
211 struct iio_dev *indio_dev = file->private_data;
217 ret = indio_dev->info->debugfs_reg_access(indio_dev,
218 indio_dev->cached_reg_addr,
221 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
223 len = snprintf(buf, sizeof(buf), "0x%X\n", val);
225 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
228 static ssize_t iio_debugfs_write_reg(struct file *file,
229 const char __user *userbuf, size_t count, loff_t *ppos)
231 struct iio_dev *indio_dev = file->private_data;
236 count = min_t(size_t, count, (sizeof(buf)-1));
237 if (copy_from_user(buf, userbuf, count))
242 ret = sscanf(buf, "%i %i", ®, &val);
246 indio_dev->cached_reg_addr = reg;
249 indio_dev->cached_reg_addr = reg;
250 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
253 dev_err(indio_dev->dev.parent, "%s: write failed\n",
265 static const struct file_operations iio_debugfs_reg_fops = {
267 .read = iio_debugfs_read_reg,
268 .write = iio_debugfs_write_reg,
271 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
273 debugfs_remove_recursive(indio_dev->debugfs_dentry);
276 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
280 if (indio_dev->info->debugfs_reg_access == NULL)
283 if (!iio_debugfs_dentry)
286 indio_dev->debugfs_dentry =
287 debugfs_create_dir(dev_name(&indio_dev->dev),
289 if (indio_dev->debugfs_dentry == NULL) {
290 dev_warn(indio_dev->dev.parent,
291 "Failed to create debugfs directory\n");
295 d = debugfs_create_file("direct_reg_access", 0644,
296 indio_dev->debugfs_dentry,
297 indio_dev, &iio_debugfs_reg_fops);
299 iio_device_unregister_debugfs(indio_dev);
306 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
311 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
314 #endif /* CONFIG_DEBUG_FS */
316 static ssize_t iio_read_channel_ext_info(struct device *dev,
317 struct device_attribute *attr,
320 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
321 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
322 const struct iio_chan_spec_ext_info *ext_info;
324 ext_info = &this_attr->c->ext_info[this_attr->address];
326 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
329 static ssize_t iio_write_channel_ext_info(struct device *dev,
330 struct device_attribute *attr,
334 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
335 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
336 const struct iio_chan_spec_ext_info *ext_info;
338 ext_info = &this_attr->c->ext_info[this_attr->address];
340 return ext_info->write(indio_dev, ext_info->private,
341 this_attr->c, buf, len);
344 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
345 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
347 const struct iio_enum *e = (const struct iio_enum *)priv;
354 for (i = 0; i < e->num_items; ++i)
355 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
357 /* replace last space with a newline */
362 EXPORT_SYMBOL_GPL(iio_enum_available_read);
364 ssize_t iio_enum_read(struct iio_dev *indio_dev,
365 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
367 const struct iio_enum *e = (const struct iio_enum *)priv;
373 i = e->get(indio_dev, chan);
376 else if (i >= e->num_items)
379 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
381 EXPORT_SYMBOL_GPL(iio_enum_read);
383 ssize_t iio_enum_write(struct iio_dev *indio_dev,
384 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
387 const struct iio_enum *e = (const struct iio_enum *)priv;
394 for (i = 0; i < e->num_items; i++) {
395 if (sysfs_streq(buf, e->items[i]))
399 if (i == e->num_items)
402 ret = e->set(indio_dev, chan, i);
403 return ret ? ret : len;
405 EXPORT_SYMBOL_GPL(iio_enum_write);
408 * iio_format_value() - Formats a IIO value into its string representation
409 * @buf: The buffer to which the formatted value gets written
410 * @type: One of the IIO_VAL_... constants. This decides how the val
411 * and val2 parameters are formatted.
412 * @size: Number of IIO value entries contained in vals
413 * @vals: Pointer to the values, exact meaning depends on the
416 * Return: 0 by default, a negative number on failure or the
417 * total number of characters written for a type that belongs
418 * to the IIO_VAL_... constant.
420 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
422 unsigned long long tmp;
423 bool scale_db = false;
427 return sprintf(buf, "%d\n", vals[0]);
428 case IIO_VAL_INT_PLUS_MICRO_DB:
430 case IIO_VAL_INT_PLUS_MICRO:
432 return sprintf(buf, "-%ld.%06u%s\n", abs(vals[0]),
434 scale_db ? " dB" : "");
436 return sprintf(buf, "%d.%06u%s\n", vals[0], vals[1],
437 scale_db ? " dB" : "");
438 case IIO_VAL_INT_PLUS_NANO:
440 return sprintf(buf, "-%ld.%09u\n", abs(vals[0]),
443 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
444 case IIO_VAL_FRACTIONAL:
445 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
446 vals[1] = do_div(tmp, 1000000000LL);
448 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
449 case IIO_VAL_FRACTIONAL_LOG2:
450 tmp = (s64)vals[0] * 1000000000LL >> vals[1];
451 vals[1] = do_div(tmp, 1000000000LL);
453 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
454 case IIO_VAL_INT_MULTIPLE:
459 for (i = 0; i < size; ++i)
460 len += snprintf(&buf[len], PAGE_SIZE - len, "%d ",
462 len += snprintf(&buf[len], PAGE_SIZE - len, "\n");
470 static ssize_t iio_read_channel_info(struct device *dev,
471 struct device_attribute *attr,
474 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
475 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
476 int vals[INDIO_MAX_RAW_ELEMENTS];
480 if (indio_dev->info->read_raw_multi)
481 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
482 INDIO_MAX_RAW_ELEMENTS,
486 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
487 &vals[0], &vals[1], this_attr->address);
492 return iio_format_value(buf, ret, val_len, vals);
496 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
497 * @str: The string to parse
498 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
499 * @integer: The integer part of the number
500 * @fract: The fractional part of the number
502 * Returns 0 on success, or a negative error code if the string could not be
505 int iio_str_to_fixpoint(const char *str, int fract_mult,
506 int *integer, int *fract)
509 bool integer_part = true, negative = false;
514 } else if (str[0] == '+') {
519 if ('0' <= *str && *str <= '9') {
521 i = i * 10 + *str - '0';
523 f += fract_mult * (*str - '0');
526 } else if (*str == '\n') {
527 if (*(str + 1) == '\0')
531 } else if (*str == '.' && integer_part) {
532 integer_part = false;
551 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
553 static ssize_t iio_write_channel_info(struct device *dev,
554 struct device_attribute *attr,
558 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
559 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
560 int ret, fract_mult = 100000;
563 /* Assumes decimal - precision based on number of digits */
564 if (!indio_dev->info->write_raw)
567 if (indio_dev->info->write_raw_get_fmt)
568 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
569 this_attr->c, this_attr->address)) {
570 case IIO_VAL_INT_PLUS_MICRO:
573 case IIO_VAL_INT_PLUS_NANO:
574 fract_mult = 100000000;
580 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
584 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
585 integer, fract, this_attr->address);
593 int __iio_device_attr_init(struct device_attribute *dev_attr,
595 struct iio_chan_spec const *chan,
596 ssize_t (*readfunc)(struct device *dev,
597 struct device_attribute *attr,
599 ssize_t (*writefunc)(struct device *dev,
600 struct device_attribute *attr,
603 enum iio_shared_by shared_by)
608 sysfs_attr_init(&dev_attr->attr);
610 /* Build up postfix of <extend_name>_<modifier>_postfix */
611 if (chan->modified && (shared_by == IIO_SEPARATE)) {
612 if (chan->extend_name)
613 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
614 iio_modifier_names[chan
619 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
620 iio_modifier_names[chan
624 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
625 full_postfix = kstrdup(postfix, GFP_KERNEL);
627 full_postfix = kasprintf(GFP_KERNEL,
632 if (full_postfix == NULL)
635 if (chan->differential) { /* Differential can not have modifier */
637 case IIO_SHARED_BY_ALL:
638 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
640 case IIO_SHARED_BY_DIR:
641 name = kasprintf(GFP_KERNEL, "%s_%s",
642 iio_direction[chan->output],
645 case IIO_SHARED_BY_TYPE:
646 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
647 iio_direction[chan->output],
648 iio_chan_type_name_spec[chan->type],
649 iio_chan_type_name_spec[chan->type],
653 if (!chan->indexed) {
654 WARN_ON("Differential channels must be indexed\n");
656 goto error_free_full_postfix;
658 name = kasprintf(GFP_KERNEL,
660 iio_direction[chan->output],
661 iio_chan_type_name_spec[chan->type],
663 iio_chan_type_name_spec[chan->type],
668 } else { /* Single ended */
670 case IIO_SHARED_BY_ALL:
671 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
673 case IIO_SHARED_BY_DIR:
674 name = kasprintf(GFP_KERNEL, "%s_%s",
675 iio_direction[chan->output],
678 case IIO_SHARED_BY_TYPE:
679 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
680 iio_direction[chan->output],
681 iio_chan_type_name_spec[chan->type],
687 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
688 iio_direction[chan->output],
689 iio_chan_type_name_spec[chan->type],
693 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
694 iio_direction[chan->output],
695 iio_chan_type_name_spec[chan->type],
702 goto error_free_full_postfix;
704 dev_attr->attr.name = name;
707 dev_attr->attr.mode |= S_IRUGO;
708 dev_attr->show = readfunc;
712 dev_attr->attr.mode |= S_IWUSR;
713 dev_attr->store = writefunc;
716 error_free_full_postfix:
722 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
724 kfree(dev_attr->attr.name);
727 int __iio_add_chan_devattr(const char *postfix,
728 struct iio_chan_spec const *chan,
729 ssize_t (*readfunc)(struct device *dev,
730 struct device_attribute *attr,
732 ssize_t (*writefunc)(struct device *dev,
733 struct device_attribute *attr,
737 enum iio_shared_by shared_by,
739 struct list_head *attr_list)
742 struct iio_dev_attr *iio_attr, *t;
744 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
745 if (iio_attr == NULL)
747 ret = __iio_device_attr_init(&iio_attr->dev_attr,
749 readfunc, writefunc, shared_by);
751 goto error_iio_dev_attr_free;
753 iio_attr->address = mask;
754 list_for_each_entry(t, attr_list, l)
755 if (strcmp(t->dev_attr.attr.name,
756 iio_attr->dev_attr.attr.name) == 0) {
757 if (shared_by == IIO_SEPARATE)
758 dev_err(dev, "tried to double register : %s\n",
759 t->dev_attr.attr.name);
761 goto error_device_attr_deinit;
763 list_add(&iio_attr->l, attr_list);
767 error_device_attr_deinit:
768 __iio_device_attr_deinit(&iio_attr->dev_attr);
769 error_iio_dev_attr_free:
774 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
775 struct iio_chan_spec const *chan,
776 enum iio_shared_by shared_by,
777 const long *infomask)
779 int i, ret, attrcount = 0;
781 for_each_set_bit(i, infomask, sizeof(infomask)*8) {
782 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
784 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
786 &iio_read_channel_info,
787 &iio_write_channel_info,
791 &indio_dev->channel_attr_list);
792 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
802 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
803 struct iio_chan_spec const *chan)
805 int ret, attrcount = 0;
806 const struct iio_chan_spec_ext_info *ext_info;
808 if (chan->channel < 0)
810 ret = iio_device_add_info_mask_type(indio_dev, chan,
812 &chan->info_mask_separate);
817 ret = iio_device_add_info_mask_type(indio_dev, chan,
819 &chan->info_mask_shared_by_type);
824 ret = iio_device_add_info_mask_type(indio_dev, chan,
826 &chan->info_mask_shared_by_dir);
831 ret = iio_device_add_info_mask_type(indio_dev, chan,
833 &chan->info_mask_shared_by_all);
838 if (chan->ext_info) {
840 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
841 ret = __iio_add_chan_devattr(ext_info->name,
844 &iio_read_channel_ext_info : NULL,
846 &iio_write_channel_ext_info : NULL,
850 &indio_dev->channel_attr_list);
852 if (ret == -EBUSY && ext_info->shared)
866 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
867 * @attr_list: List of IIO device attributes
869 * This function frees the memory allocated for each of the IIO device
870 * attributes in the list.
872 void iio_free_chan_devattr_list(struct list_head *attr_list)
874 struct iio_dev_attr *p, *n;
876 list_for_each_entry_safe(p, n, attr_list, l) {
877 kfree(p->dev_attr.attr.name);
883 static ssize_t iio_show_dev_name(struct device *dev,
884 struct device_attribute *attr,
887 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
888 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
891 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
893 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
895 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
896 struct iio_dev_attr *p;
897 struct attribute **attr;
899 /* First count elements in any existing group */
900 if (indio_dev->info->attrs) {
901 attr = indio_dev->info->attrs->attrs;
902 while (*attr++ != NULL)
905 attrcount = attrcount_orig;
907 * New channel registration method - relies on the fact a group does
908 * not need to be initialized if its name is NULL.
910 if (indio_dev->channels)
911 for (i = 0; i < indio_dev->num_channels; i++) {
912 ret = iio_device_add_channel_sysfs(indio_dev,
916 goto error_clear_attrs;
923 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
924 sizeof(indio_dev->chan_attr_group.attrs[0]),
926 if (indio_dev->chan_attr_group.attrs == NULL) {
928 goto error_clear_attrs;
930 /* Copy across original attributes */
931 if (indio_dev->info->attrs)
932 memcpy(indio_dev->chan_attr_group.attrs,
933 indio_dev->info->attrs->attrs,
934 sizeof(indio_dev->chan_attr_group.attrs[0])
936 attrn = attrcount_orig;
937 /* Add all elements from the list. */
938 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
939 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
941 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
943 indio_dev->groups[indio_dev->groupcounter++] =
944 &indio_dev->chan_attr_group;
949 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
954 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
957 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
958 kfree(indio_dev->chan_attr_group.attrs);
959 indio_dev->chan_attr_group.attrs = NULL;
962 static void iio_dev_release(struct device *device)
964 struct iio_dev *indio_dev = dev_to_iio_dev(device);
965 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
966 iio_device_unregister_trigger_consumer(indio_dev);
967 iio_device_unregister_eventset(indio_dev);
968 iio_device_unregister_sysfs(indio_dev);
970 iio_buffer_put(indio_dev->buffer);
972 ida_simple_remove(&iio_ida, indio_dev->id);
976 struct device_type iio_device_type = {
977 .name = "iio_device",
978 .release = iio_dev_release,
982 * iio_device_alloc() - allocate an iio_dev from a driver
983 * @sizeof_priv: Space to allocate for private structure.
985 struct iio_dev *iio_device_alloc(int sizeof_priv)
990 alloc_size = sizeof(struct iio_dev);
992 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
993 alloc_size += sizeof_priv;
995 /* ensure 32-byte alignment of whole construct ? */
996 alloc_size += IIO_ALIGN - 1;
998 dev = kzalloc(alloc_size, GFP_KERNEL);
1001 dev->dev.groups = dev->groups;
1002 dev->dev.type = &iio_device_type;
1003 dev->dev.bus = &iio_bus_type;
1004 device_initialize(&dev->dev);
1005 dev_set_drvdata(&dev->dev, (void *)dev);
1006 mutex_init(&dev->mlock);
1007 mutex_init(&dev->info_exist_lock);
1008 INIT_LIST_HEAD(&dev->channel_attr_list);
1010 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1012 /* cannot use a dev_err as the name isn't available */
1013 pr_err("failed to get device id\n");
1017 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1018 INIT_LIST_HEAD(&dev->buffer_list);
1023 EXPORT_SYMBOL(iio_device_alloc);
1026 * iio_device_free() - free an iio_dev from a driver
1027 * @dev: the iio_dev associated with the device
1029 void iio_device_free(struct iio_dev *dev)
1032 put_device(&dev->dev);
1034 EXPORT_SYMBOL(iio_device_free);
1036 static void devm_iio_device_release(struct device *dev, void *res)
1038 iio_device_free(*(struct iio_dev **)res);
1041 static int devm_iio_device_match(struct device *dev, void *res, void *data)
1043 struct iio_dev **r = res;
1052 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1053 * @dev: Device to allocate iio_dev for
1054 * @sizeof_priv: Space to allocate for private structure.
1056 * Managed iio_device_alloc. iio_dev allocated with this function is
1057 * automatically freed on driver detach.
1059 * If an iio_dev allocated with this function needs to be freed separately,
1060 * devm_iio_device_free() must be used.
1063 * Pointer to allocated iio_dev on success, NULL on failure.
1065 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1067 struct iio_dev **ptr, *iio_dev;
1069 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1074 iio_dev = iio_device_alloc(sizeof_priv);
1077 devres_add(dev, ptr);
1084 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1087 * devm_iio_device_free - Resource-managed iio_device_free()
1088 * @dev: Device this iio_dev belongs to
1089 * @iio_dev: the iio_dev associated with the device
1091 * Free iio_dev allocated with devm_iio_device_alloc().
1093 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1097 rc = devres_release(dev, devm_iio_device_release,
1098 devm_iio_device_match, iio_dev);
1101 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1104 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1105 * @inode: Inode structure for identifying the device in the file system
1106 * @filp: File structure for iio device used to keep and later access
1109 * Return: 0 on success or -EBUSY if the device is already opened
1111 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1113 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1114 struct iio_dev, chrdev);
1116 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1119 iio_device_get(indio_dev);
1121 filp->private_data = indio_dev;
1127 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1128 * @inode: Inode structure pointer for the char device
1129 * @filp: File structure pointer for the char device
1131 * Return: 0 for successful release
1133 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1135 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1136 struct iio_dev, chrdev);
1137 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1138 iio_device_put(indio_dev);
1143 /* Somewhat of a cross file organization violation - ioctls here are actually
1145 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1147 struct iio_dev *indio_dev = filp->private_data;
1148 int __user *ip = (int __user *)arg;
1151 if (!indio_dev->info)
1154 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1155 fd = iio_event_getfd(indio_dev);
1156 if (copy_to_user(ip, &fd, sizeof(fd)))
1163 static const struct file_operations iio_buffer_fileops = {
1164 .read = iio_buffer_read_first_n_outer_addr,
1165 .release = iio_chrdev_release,
1166 .open = iio_chrdev_open,
1167 .poll = iio_buffer_poll_addr,
1168 .owner = THIS_MODULE,
1169 .llseek = noop_llseek,
1170 .unlocked_ioctl = iio_ioctl,
1171 .compat_ioctl = iio_ioctl,
1174 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1177 const struct iio_chan_spec *channels = indio_dev->channels;
1179 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1182 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1183 if (channels[i].scan_index < 0)
1185 for (j = i + 1; j < indio_dev->num_channels; j++)
1186 if (channels[i].scan_index == channels[j].scan_index) {
1187 dev_err(&indio_dev->dev,
1188 "Duplicate scan index %d\n",
1189 channels[i].scan_index);
1197 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1200 * iio_device_register() - register a device with the IIO subsystem
1201 * @indio_dev: Device structure filled by the device driver
1203 int iio_device_register(struct iio_dev *indio_dev)
1207 /* If the calling driver did not initialize of_node, do it here */
1208 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1209 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1211 ret = iio_check_unique_scan_index(indio_dev);
1215 /* configure elements for the chrdev */
1216 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1218 ret = iio_device_register_debugfs(indio_dev);
1220 dev_err(indio_dev->dev.parent,
1221 "Failed to register debugfs interfaces\n");
1225 ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1227 dev_err(indio_dev->dev.parent,
1228 "Failed to create buffer sysfs interfaces\n");
1229 goto error_unreg_debugfs;
1232 ret = iio_device_register_sysfs(indio_dev);
1234 dev_err(indio_dev->dev.parent,
1235 "Failed to register sysfs interfaces\n");
1236 goto error_buffer_free_sysfs;
1238 ret = iio_device_register_eventset(indio_dev);
1240 dev_err(indio_dev->dev.parent,
1241 "Failed to register event set\n");
1242 goto error_free_sysfs;
1244 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
1245 iio_device_register_trigger_consumer(indio_dev);
1247 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1248 indio_dev->setup_ops == NULL)
1249 indio_dev->setup_ops = &noop_ring_setup_ops;
1251 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1252 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1253 indio_dev->chrdev.kobj.parent = &indio_dev->dev.kobj;
1254 ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
1256 goto error_unreg_eventset;
1258 ret = device_add(&indio_dev->dev);
1260 goto error_cdev_del;
1264 cdev_del(&indio_dev->chrdev);
1265 error_unreg_eventset:
1266 iio_device_unregister_eventset(indio_dev);
1268 iio_device_unregister_sysfs(indio_dev);
1269 error_buffer_free_sysfs:
1270 iio_buffer_free_sysfs_and_mask(indio_dev);
1271 error_unreg_debugfs:
1272 iio_device_unregister_debugfs(indio_dev);
1275 EXPORT_SYMBOL(iio_device_register);
1278 * iio_device_unregister() - unregister a device from the IIO subsystem
1279 * @indio_dev: Device structure representing the device.
1281 void iio_device_unregister(struct iio_dev *indio_dev)
1283 mutex_lock(&indio_dev->info_exist_lock);
1285 device_del(&indio_dev->dev);
1287 if (indio_dev->chrdev.dev)
1288 cdev_del(&indio_dev->chrdev);
1289 iio_device_unregister_debugfs(indio_dev);
1291 iio_disable_all_buffers(indio_dev);
1293 indio_dev->info = NULL;
1295 iio_device_wakeup_eventset(indio_dev);
1296 iio_buffer_wakeup_poll(indio_dev);
1298 mutex_unlock(&indio_dev->info_exist_lock);
1300 iio_buffer_free_sysfs_and_mask(indio_dev);
1302 EXPORT_SYMBOL(iio_device_unregister);
1304 static void devm_iio_device_unreg(struct device *dev, void *res)
1306 iio_device_unregister(*(struct iio_dev **)res);
1310 * devm_iio_device_register - Resource-managed iio_device_register()
1311 * @dev: Device to allocate iio_dev for
1312 * @indio_dev: Device structure filled by the device driver
1314 * Managed iio_device_register. The IIO device registered with this
1315 * function is automatically unregistered on driver detach. This function
1316 * calls iio_device_register() internally. Refer to that function for more
1319 * If an iio_dev registered with this function needs to be unregistered
1320 * separately, devm_iio_device_unregister() must be used.
1323 * 0 on success, negative error number on failure.
1325 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev)
1327 struct iio_dev **ptr;
1330 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1335 ret = iio_device_register(indio_dev);
1337 devres_add(dev, ptr);
1343 EXPORT_SYMBOL_GPL(devm_iio_device_register);
1346 * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1347 * @dev: Device this iio_dev belongs to
1348 * @indio_dev: the iio_dev associated with the device
1350 * Unregister iio_dev registered with devm_iio_device_register().
1352 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1356 rc = devres_release(dev, devm_iio_device_unreg,
1357 devm_iio_device_match, indio_dev);
1360 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1362 subsys_initcall(iio_init);
1363 module_exit(iio_exit);
1365 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1366 MODULE_DESCRIPTION("Industrial I/O core");
1367 MODULE_LICENSE("GPL");