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",
78 [IIO_CONCENTRATION] = "concentration",
79 [IIO_RESISTANCE] = "resistance",
83 static const char * const iio_modifier_names[] = {
87 [IIO_MOD_X_AND_Y] = "x&y",
88 [IIO_MOD_X_AND_Z] = "x&z",
89 [IIO_MOD_Y_AND_Z] = "y&z",
90 [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",
91 [IIO_MOD_X_OR_Y] = "x|y",
92 [IIO_MOD_X_OR_Z] = "x|z",
93 [IIO_MOD_Y_OR_Z] = "y|z",
94 [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",
95 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
96 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
97 [IIO_MOD_LIGHT_BOTH] = "both",
98 [IIO_MOD_LIGHT_IR] = "ir",
99 [IIO_MOD_LIGHT_CLEAR] = "clear",
100 [IIO_MOD_LIGHT_RED] = "red",
101 [IIO_MOD_LIGHT_GREEN] = "green",
102 [IIO_MOD_LIGHT_BLUE] = "blue",
103 [IIO_MOD_QUATERNION] = "quaternion",
104 [IIO_MOD_TEMP_AMBIENT] = "ambient",
105 [IIO_MOD_TEMP_OBJECT] = "object",
106 [IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
107 [IIO_MOD_NORTH_TRUE] = "from_north_true",
108 [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
109 [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
110 [IIO_MOD_RUNNING] = "running",
111 [IIO_MOD_JOGGING] = "jogging",
112 [IIO_MOD_WALKING] = "walking",
113 [IIO_MOD_STILL] = "still",
114 [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
117 [IIO_MOD_CO2] = "co2",
118 [IIO_MOD_VOC] = "voc",
121 /* relies on pairs of these shared then separate */
122 static const char * const iio_chan_info_postfix[] = {
123 [IIO_CHAN_INFO_RAW] = "raw",
124 [IIO_CHAN_INFO_PROCESSED] = "input",
125 [IIO_CHAN_INFO_SCALE] = "scale",
126 [IIO_CHAN_INFO_OFFSET] = "offset",
127 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
128 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
129 [IIO_CHAN_INFO_PEAK] = "peak_raw",
130 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
131 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
132 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
133 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
134 = "filter_low_pass_3db_frequency",
135 [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]
136 = "filter_high_pass_3db_frequency",
137 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
138 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
139 [IIO_CHAN_INFO_PHASE] = "phase",
140 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
141 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
142 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
143 [IIO_CHAN_INFO_ENABLE] = "en",
144 [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
145 [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
146 [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",
147 [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",
148 [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",
149 [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",
153 * iio_find_channel_from_si() - get channel from its scan index
155 * @si: scan index to match
157 const struct iio_chan_spec
158 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
162 for (i = 0; i < indio_dev->num_channels; i++)
163 if (indio_dev->channels[i].scan_index == si)
164 return &indio_dev->channels[i];
168 /* This turns up an awful lot */
169 ssize_t iio_read_const_attr(struct device *dev,
170 struct device_attribute *attr,
173 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
175 EXPORT_SYMBOL(iio_read_const_attr);
177 static int __init iio_init(void)
181 /* Register sysfs bus */
182 ret = bus_register(&iio_bus_type);
184 pr_err("could not register bus type\n");
188 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
190 pr_err("failed to allocate char dev region\n");
191 goto error_unregister_bus_type;
194 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
198 error_unregister_bus_type:
199 bus_unregister(&iio_bus_type);
204 static void __exit iio_exit(void)
207 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
208 bus_unregister(&iio_bus_type);
209 debugfs_remove(iio_debugfs_dentry);
212 #if defined(CONFIG_DEBUG_FS)
213 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
214 size_t count, loff_t *ppos)
216 struct iio_dev *indio_dev = file->private_data;
222 ret = indio_dev->info->debugfs_reg_access(indio_dev,
223 indio_dev->cached_reg_addr,
226 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
228 len = snprintf(buf, sizeof(buf), "0x%X\n", val);
230 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
233 static ssize_t iio_debugfs_write_reg(struct file *file,
234 const char __user *userbuf, size_t count, loff_t *ppos)
236 struct iio_dev *indio_dev = file->private_data;
241 count = min_t(size_t, count, (sizeof(buf)-1));
242 if (copy_from_user(buf, userbuf, count))
247 ret = sscanf(buf, "%i %i", ®, &val);
251 indio_dev->cached_reg_addr = reg;
254 indio_dev->cached_reg_addr = reg;
255 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
258 dev_err(indio_dev->dev.parent, "%s: write failed\n",
270 static const struct file_operations iio_debugfs_reg_fops = {
272 .read = iio_debugfs_read_reg,
273 .write = iio_debugfs_write_reg,
276 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
278 debugfs_remove_recursive(indio_dev->debugfs_dentry);
281 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
285 if (indio_dev->info->debugfs_reg_access == NULL)
288 if (!iio_debugfs_dentry)
291 indio_dev->debugfs_dentry =
292 debugfs_create_dir(dev_name(&indio_dev->dev),
294 if (indio_dev->debugfs_dentry == NULL) {
295 dev_warn(indio_dev->dev.parent,
296 "Failed to create debugfs directory\n");
300 d = debugfs_create_file("direct_reg_access", 0644,
301 indio_dev->debugfs_dentry,
302 indio_dev, &iio_debugfs_reg_fops);
304 iio_device_unregister_debugfs(indio_dev);
311 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
316 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
319 #endif /* CONFIG_DEBUG_FS */
321 static ssize_t iio_read_channel_ext_info(struct device *dev,
322 struct device_attribute *attr,
325 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
326 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
327 const struct iio_chan_spec_ext_info *ext_info;
329 ext_info = &this_attr->c->ext_info[this_attr->address];
331 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
334 static ssize_t iio_write_channel_ext_info(struct device *dev,
335 struct device_attribute *attr,
339 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
340 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
341 const struct iio_chan_spec_ext_info *ext_info;
343 ext_info = &this_attr->c->ext_info[this_attr->address];
345 return ext_info->write(indio_dev, ext_info->private,
346 this_attr->c, buf, len);
349 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
350 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
352 const struct iio_enum *e = (const struct iio_enum *)priv;
359 for (i = 0; i < e->num_items; ++i)
360 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
362 /* replace last space with a newline */
367 EXPORT_SYMBOL_GPL(iio_enum_available_read);
369 ssize_t iio_enum_read(struct iio_dev *indio_dev,
370 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
372 const struct iio_enum *e = (const struct iio_enum *)priv;
378 i = e->get(indio_dev, chan);
381 else if (i >= e->num_items)
384 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
386 EXPORT_SYMBOL_GPL(iio_enum_read);
388 ssize_t iio_enum_write(struct iio_dev *indio_dev,
389 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
392 const struct iio_enum *e = (const struct iio_enum *)priv;
399 for (i = 0; i < e->num_items; i++) {
400 if (sysfs_streq(buf, e->items[i]))
404 if (i == e->num_items)
407 ret = e->set(indio_dev, chan, i);
408 return ret ? ret : len;
410 EXPORT_SYMBOL_GPL(iio_enum_write);
413 * iio_format_value() - Formats a IIO value into its string representation
414 * @buf: The buffer to which the formatted value gets written
415 * @type: One of the IIO_VAL_... constants. This decides how the val
416 * and val2 parameters are formatted.
417 * @size: Number of IIO value entries contained in vals
418 * @vals: Pointer to the values, exact meaning depends on the
421 * Return: 0 by default, a negative number on failure or the
422 * total number of characters written for a type that belongs
423 * to the IIO_VAL_... constant.
425 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
427 unsigned long long tmp;
428 bool scale_db = false;
432 return sprintf(buf, "%d\n", vals[0]);
433 case IIO_VAL_INT_PLUS_MICRO_DB:
435 case IIO_VAL_INT_PLUS_MICRO:
437 return sprintf(buf, "-%d.%06u%s\n", abs(vals[0]),
438 -vals[1], scale_db ? " dB" : "");
440 return sprintf(buf, "%d.%06u%s\n", vals[0], vals[1],
441 scale_db ? " dB" : "");
442 case IIO_VAL_INT_PLUS_NANO:
444 return sprintf(buf, "-%d.%09u\n", abs(vals[0]),
447 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
448 case IIO_VAL_FRACTIONAL:
449 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
450 vals[1] = do_div(tmp, 1000000000LL);
452 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
453 case IIO_VAL_FRACTIONAL_LOG2:
454 tmp = (s64)vals[0] * 1000000000LL >> vals[1];
455 vals[1] = do_div(tmp, 1000000000LL);
457 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
458 case IIO_VAL_INT_MULTIPLE:
463 for (i = 0; i < size; ++i)
464 len += snprintf(&buf[len], PAGE_SIZE - len, "%d ",
466 len += snprintf(&buf[len], PAGE_SIZE - len, "\n");
473 EXPORT_SYMBOL_GPL(iio_format_value);
475 static ssize_t iio_read_channel_info(struct device *dev,
476 struct device_attribute *attr,
479 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
480 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
481 int vals[INDIO_MAX_RAW_ELEMENTS];
485 if (indio_dev->info->read_raw_multi)
486 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
487 INDIO_MAX_RAW_ELEMENTS,
491 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
492 &vals[0], &vals[1], this_attr->address);
497 return iio_format_value(buf, ret, val_len, vals);
501 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
502 * @str: The string to parse
503 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
504 * @integer: The integer part of the number
505 * @fract: The fractional part of the number
507 * Returns 0 on success, or a negative error code if the string could not be
510 int iio_str_to_fixpoint(const char *str, int fract_mult,
511 int *integer, int *fract)
514 bool integer_part = true, negative = false;
516 if (fract_mult == 0) {
519 return kstrtoint(str, 0, integer);
525 } else if (str[0] == '+') {
530 if ('0' <= *str && *str <= '9') {
532 i = i * 10 + *str - '0';
534 f += fract_mult * (*str - '0');
537 } else if (*str == '\n') {
538 if (*(str + 1) == '\0')
542 } else if (*str == '.' && integer_part) {
543 integer_part = false;
562 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
564 static ssize_t iio_write_channel_info(struct device *dev,
565 struct device_attribute *attr,
569 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
570 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
571 int ret, fract_mult = 100000;
574 /* Assumes decimal - precision based on number of digits */
575 if (!indio_dev->info->write_raw)
578 if (indio_dev->info->write_raw_get_fmt)
579 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
580 this_attr->c, this_attr->address)) {
584 case IIO_VAL_INT_PLUS_MICRO:
587 case IIO_VAL_INT_PLUS_NANO:
588 fract_mult = 100000000;
594 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
598 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
599 integer, fract, this_attr->address);
607 int __iio_device_attr_init(struct device_attribute *dev_attr,
609 struct iio_chan_spec const *chan,
610 ssize_t (*readfunc)(struct device *dev,
611 struct device_attribute *attr,
613 ssize_t (*writefunc)(struct device *dev,
614 struct device_attribute *attr,
617 enum iio_shared_by shared_by)
622 sysfs_attr_init(&dev_attr->attr);
624 /* Build up postfix of <extend_name>_<modifier>_postfix */
625 if (chan->modified && (shared_by == IIO_SEPARATE)) {
626 if (chan->extend_name)
627 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
628 iio_modifier_names[chan
633 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
634 iio_modifier_names[chan
638 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
639 full_postfix = kstrdup(postfix, GFP_KERNEL);
641 full_postfix = kasprintf(GFP_KERNEL,
646 if (full_postfix == NULL)
649 if (chan->differential) { /* Differential can not have modifier */
651 case IIO_SHARED_BY_ALL:
652 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
654 case IIO_SHARED_BY_DIR:
655 name = kasprintf(GFP_KERNEL, "%s_%s",
656 iio_direction[chan->output],
659 case IIO_SHARED_BY_TYPE:
660 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
661 iio_direction[chan->output],
662 iio_chan_type_name_spec[chan->type],
663 iio_chan_type_name_spec[chan->type],
667 if (!chan->indexed) {
668 WARN(1, "Differential channels must be indexed\n");
670 goto error_free_full_postfix;
672 name = kasprintf(GFP_KERNEL,
674 iio_direction[chan->output],
675 iio_chan_type_name_spec[chan->type],
677 iio_chan_type_name_spec[chan->type],
682 } else { /* Single ended */
684 case IIO_SHARED_BY_ALL:
685 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
687 case IIO_SHARED_BY_DIR:
688 name = kasprintf(GFP_KERNEL, "%s_%s",
689 iio_direction[chan->output],
692 case IIO_SHARED_BY_TYPE:
693 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
694 iio_direction[chan->output],
695 iio_chan_type_name_spec[chan->type],
701 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
702 iio_direction[chan->output],
703 iio_chan_type_name_spec[chan->type],
707 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
708 iio_direction[chan->output],
709 iio_chan_type_name_spec[chan->type],
716 goto error_free_full_postfix;
718 dev_attr->attr.name = name;
721 dev_attr->attr.mode |= S_IRUGO;
722 dev_attr->show = readfunc;
726 dev_attr->attr.mode |= S_IWUSR;
727 dev_attr->store = writefunc;
730 error_free_full_postfix:
736 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
738 kfree(dev_attr->attr.name);
741 int __iio_add_chan_devattr(const char *postfix,
742 struct iio_chan_spec const *chan,
743 ssize_t (*readfunc)(struct device *dev,
744 struct device_attribute *attr,
746 ssize_t (*writefunc)(struct device *dev,
747 struct device_attribute *attr,
751 enum iio_shared_by shared_by,
753 struct list_head *attr_list)
756 struct iio_dev_attr *iio_attr, *t;
758 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
759 if (iio_attr == NULL)
761 ret = __iio_device_attr_init(&iio_attr->dev_attr,
763 readfunc, writefunc, shared_by);
765 goto error_iio_dev_attr_free;
767 iio_attr->address = mask;
768 list_for_each_entry(t, attr_list, l)
769 if (strcmp(t->dev_attr.attr.name,
770 iio_attr->dev_attr.attr.name) == 0) {
771 if (shared_by == IIO_SEPARATE)
772 dev_err(dev, "tried to double register : %s\n",
773 t->dev_attr.attr.name);
775 goto error_device_attr_deinit;
777 list_add(&iio_attr->l, attr_list);
781 error_device_attr_deinit:
782 __iio_device_attr_deinit(&iio_attr->dev_attr);
783 error_iio_dev_attr_free:
788 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
789 struct iio_chan_spec const *chan,
790 enum iio_shared_by shared_by,
791 const long *infomask)
793 int i, ret, attrcount = 0;
795 for_each_set_bit(i, infomask, sizeof(infomask)*8) {
796 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
798 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
800 &iio_read_channel_info,
801 &iio_write_channel_info,
805 &indio_dev->channel_attr_list);
806 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
816 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
817 struct iio_chan_spec const *chan)
819 int ret, attrcount = 0;
820 const struct iio_chan_spec_ext_info *ext_info;
822 if (chan->channel < 0)
824 ret = iio_device_add_info_mask_type(indio_dev, chan,
826 &chan->info_mask_separate);
831 ret = iio_device_add_info_mask_type(indio_dev, chan,
833 &chan->info_mask_shared_by_type);
838 ret = iio_device_add_info_mask_type(indio_dev, chan,
840 &chan->info_mask_shared_by_dir);
845 ret = iio_device_add_info_mask_type(indio_dev, chan,
847 &chan->info_mask_shared_by_all);
852 if (chan->ext_info) {
854 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
855 ret = __iio_add_chan_devattr(ext_info->name,
858 &iio_read_channel_ext_info : NULL,
860 &iio_write_channel_ext_info : NULL,
864 &indio_dev->channel_attr_list);
866 if (ret == -EBUSY && ext_info->shared)
880 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
881 * @attr_list: List of IIO device attributes
883 * This function frees the memory allocated for each of the IIO device
884 * attributes in the list.
886 void iio_free_chan_devattr_list(struct list_head *attr_list)
888 struct iio_dev_attr *p, *n;
890 list_for_each_entry_safe(p, n, attr_list, l) {
891 kfree(p->dev_attr.attr.name);
897 static ssize_t iio_show_dev_name(struct device *dev,
898 struct device_attribute *attr,
901 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
902 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
905 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
907 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
909 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
910 struct iio_dev_attr *p;
911 struct attribute **attr;
913 /* First count elements in any existing group */
914 if (indio_dev->info->attrs) {
915 attr = indio_dev->info->attrs->attrs;
916 while (*attr++ != NULL)
919 attrcount = attrcount_orig;
921 * New channel registration method - relies on the fact a group does
922 * not need to be initialized if its name is NULL.
924 if (indio_dev->channels)
925 for (i = 0; i < indio_dev->num_channels; i++) {
926 ret = iio_device_add_channel_sysfs(indio_dev,
930 goto error_clear_attrs;
937 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
938 sizeof(indio_dev->chan_attr_group.attrs[0]),
940 if (indio_dev->chan_attr_group.attrs == NULL) {
942 goto error_clear_attrs;
944 /* Copy across original attributes */
945 if (indio_dev->info->attrs)
946 memcpy(indio_dev->chan_attr_group.attrs,
947 indio_dev->info->attrs->attrs,
948 sizeof(indio_dev->chan_attr_group.attrs[0])
950 attrn = attrcount_orig;
951 /* Add all elements from the list. */
952 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
953 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
955 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
957 indio_dev->groups[indio_dev->groupcounter++] =
958 &indio_dev->chan_attr_group;
963 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
968 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
971 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
972 kfree(indio_dev->chan_attr_group.attrs);
973 indio_dev->chan_attr_group.attrs = NULL;
976 static void iio_dev_release(struct device *device)
978 struct iio_dev *indio_dev = dev_to_iio_dev(device);
979 if (indio_dev->modes & (INDIO_BUFFER_TRIGGERED | INDIO_EVENT_TRIGGERED))
980 iio_device_unregister_trigger_consumer(indio_dev);
981 iio_device_unregister_eventset(indio_dev);
982 iio_device_unregister_sysfs(indio_dev);
984 iio_buffer_put(indio_dev->buffer);
986 ida_simple_remove(&iio_ida, indio_dev->id);
990 struct device_type iio_device_type = {
991 .name = "iio_device",
992 .release = iio_dev_release,
996 * iio_device_alloc() - allocate an iio_dev from a driver
997 * @sizeof_priv: Space to allocate for private structure.
999 struct iio_dev *iio_device_alloc(int sizeof_priv)
1001 struct iio_dev *dev;
1004 alloc_size = sizeof(struct iio_dev);
1006 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
1007 alloc_size += sizeof_priv;
1009 /* ensure 32-byte alignment of whole construct ? */
1010 alloc_size += IIO_ALIGN - 1;
1012 dev = kzalloc(alloc_size, GFP_KERNEL);
1015 dev->dev.groups = dev->groups;
1016 dev->dev.type = &iio_device_type;
1017 dev->dev.bus = &iio_bus_type;
1018 device_initialize(&dev->dev);
1019 dev_set_drvdata(&dev->dev, (void *)dev);
1020 mutex_init(&dev->mlock);
1021 mutex_init(&dev->info_exist_lock);
1022 INIT_LIST_HEAD(&dev->channel_attr_list);
1024 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
1026 /* cannot use a dev_err as the name isn't available */
1027 pr_err("failed to get device id\n");
1031 dev_set_name(&dev->dev, "iio:device%d", dev->id);
1032 INIT_LIST_HEAD(&dev->buffer_list);
1037 EXPORT_SYMBOL(iio_device_alloc);
1040 * iio_device_free() - free an iio_dev from a driver
1041 * @dev: the iio_dev associated with the device
1043 void iio_device_free(struct iio_dev *dev)
1046 put_device(&dev->dev);
1048 EXPORT_SYMBOL(iio_device_free);
1050 static void devm_iio_device_release(struct device *dev, void *res)
1052 iio_device_free(*(struct iio_dev **)res);
1055 static int devm_iio_device_match(struct device *dev, void *res, void *data)
1057 struct iio_dev **r = res;
1066 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1067 * @dev: Device to allocate iio_dev for
1068 * @sizeof_priv: Space to allocate for private structure.
1070 * Managed iio_device_alloc. iio_dev allocated with this function is
1071 * automatically freed on driver detach.
1073 * If an iio_dev allocated with this function needs to be freed separately,
1074 * devm_iio_device_free() must be used.
1077 * Pointer to allocated iio_dev on success, NULL on failure.
1079 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1081 struct iio_dev **ptr, *iio_dev;
1083 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1088 iio_dev = iio_device_alloc(sizeof_priv);
1091 devres_add(dev, ptr);
1098 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1101 * devm_iio_device_free - Resource-managed iio_device_free()
1102 * @dev: Device this iio_dev belongs to
1103 * @iio_dev: the iio_dev associated with the device
1105 * Free iio_dev allocated with devm_iio_device_alloc().
1107 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1111 rc = devres_release(dev, devm_iio_device_release,
1112 devm_iio_device_match, iio_dev);
1115 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1118 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1119 * @inode: Inode structure for identifying the device in the file system
1120 * @filp: File structure for iio device used to keep and later access
1123 * Return: 0 on success or -EBUSY if the device is already opened
1125 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1127 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1128 struct iio_dev, chrdev);
1130 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1133 iio_device_get(indio_dev);
1135 filp->private_data = indio_dev;
1141 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1142 * @inode: Inode structure pointer for the char device
1143 * @filp: File structure pointer for the char device
1145 * Return: 0 for successful release
1147 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1149 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1150 struct iio_dev, chrdev);
1151 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1152 iio_device_put(indio_dev);
1157 /* Somewhat of a cross file organization violation - ioctls here are actually
1159 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1161 struct iio_dev *indio_dev = filp->private_data;
1162 int __user *ip = (int __user *)arg;
1165 if (!indio_dev->info)
1168 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1169 fd = iio_event_getfd(indio_dev);
1172 if (copy_to_user(ip, &fd, sizeof(fd)))
1179 static const struct file_operations iio_buffer_fileops = {
1180 .read = iio_buffer_read_first_n_outer_addr,
1181 .release = iio_chrdev_release,
1182 .open = iio_chrdev_open,
1183 .poll = iio_buffer_poll_addr,
1184 .owner = THIS_MODULE,
1185 .llseek = noop_llseek,
1186 .unlocked_ioctl = iio_ioctl,
1187 .compat_ioctl = iio_ioctl,
1190 static int iio_check_unique_scan_index(struct iio_dev *indio_dev)
1193 const struct iio_chan_spec *channels = indio_dev->channels;
1195 if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))
1198 for (i = 0; i < indio_dev->num_channels - 1; i++) {
1199 if (channels[i].scan_index < 0)
1201 for (j = i + 1; j < indio_dev->num_channels; j++)
1202 if (channels[i].scan_index == channels[j].scan_index) {
1203 dev_err(&indio_dev->dev,
1204 "Duplicate scan index %d\n",
1205 channels[i].scan_index);
1213 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1216 * iio_device_register() - register a device with the IIO subsystem
1217 * @indio_dev: Device structure filled by the device driver
1219 int iio_device_register(struct iio_dev *indio_dev)
1223 /* If the calling driver did not initialize of_node, do it here */
1224 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1225 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1227 ret = iio_check_unique_scan_index(indio_dev);
1231 /* configure elements for the chrdev */
1232 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1234 ret = iio_device_register_debugfs(indio_dev);
1236 dev_err(indio_dev->dev.parent,
1237 "Failed to register debugfs interfaces\n");
1241 ret = iio_buffer_alloc_sysfs_and_mask(indio_dev);
1243 dev_err(indio_dev->dev.parent,
1244 "Failed to create buffer sysfs interfaces\n");
1245 goto error_unreg_debugfs;
1248 ret = iio_device_register_sysfs(indio_dev);
1250 dev_err(indio_dev->dev.parent,
1251 "Failed to register sysfs interfaces\n");
1252 goto error_buffer_free_sysfs;
1254 ret = iio_device_register_eventset(indio_dev);
1256 dev_err(indio_dev->dev.parent,
1257 "Failed to register event set\n");
1258 goto error_free_sysfs;
1260 if (indio_dev->modes & (INDIO_BUFFER_TRIGGERED | INDIO_EVENT_TRIGGERED))
1261 iio_device_register_trigger_consumer(indio_dev);
1263 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1264 indio_dev->setup_ops == NULL)
1265 indio_dev->setup_ops = &noop_ring_setup_ops;
1267 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1268 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1269 indio_dev->chrdev.kobj.parent = &indio_dev->dev.kobj;
1270 ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
1272 goto error_unreg_eventset;
1274 ret = device_add(&indio_dev->dev);
1276 goto error_cdev_del;
1280 cdev_del(&indio_dev->chrdev);
1281 error_unreg_eventset:
1282 iio_device_unregister_eventset(indio_dev);
1284 iio_device_unregister_sysfs(indio_dev);
1285 error_buffer_free_sysfs:
1286 iio_buffer_free_sysfs_and_mask(indio_dev);
1287 error_unreg_debugfs:
1288 iio_device_unregister_debugfs(indio_dev);
1291 EXPORT_SYMBOL(iio_device_register);
1294 * iio_device_unregister() - unregister a device from the IIO subsystem
1295 * @indio_dev: Device structure representing the device.
1297 void iio_device_unregister(struct iio_dev *indio_dev)
1299 mutex_lock(&indio_dev->info_exist_lock);
1301 device_del(&indio_dev->dev);
1303 if (indio_dev->chrdev.dev)
1304 cdev_del(&indio_dev->chrdev);
1305 iio_device_unregister_debugfs(indio_dev);
1307 iio_disable_all_buffers(indio_dev);
1309 indio_dev->info = NULL;
1311 iio_device_wakeup_eventset(indio_dev);
1312 iio_buffer_wakeup_poll(indio_dev);
1314 mutex_unlock(&indio_dev->info_exist_lock);
1316 iio_buffer_free_sysfs_and_mask(indio_dev);
1318 EXPORT_SYMBOL(iio_device_unregister);
1320 static void devm_iio_device_unreg(struct device *dev, void *res)
1322 iio_device_unregister(*(struct iio_dev **)res);
1326 * devm_iio_device_register - Resource-managed iio_device_register()
1327 * @dev: Device to allocate iio_dev for
1328 * @indio_dev: Device structure filled by the device driver
1330 * Managed iio_device_register. The IIO device registered with this
1331 * function is automatically unregistered on driver detach. This function
1332 * calls iio_device_register() internally. Refer to that function for more
1335 * If an iio_dev registered with this function needs to be unregistered
1336 * separately, devm_iio_device_unregister() must be used.
1339 * 0 on success, negative error number on failure.
1341 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev)
1343 struct iio_dev **ptr;
1346 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1351 ret = iio_device_register(indio_dev);
1353 devres_add(dev, ptr);
1359 EXPORT_SYMBOL_GPL(devm_iio_device_register);
1362 * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1363 * @dev: Device this iio_dev belongs to
1364 * @indio_dev: the iio_dev associated with the device
1366 * Unregister iio_dev registered with devm_iio_device_register().
1368 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1372 rc = devres_release(dev, devm_iio_device_unreg,
1373 devm_iio_device_match, indio_dev);
1376 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1378 subsys_initcall(iio_init);
1379 module_exit(iio_exit);
1381 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1382 MODULE_DESCRIPTION("Industrial I/O core");
1383 MODULE_LICENSE("GPL");