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",
75 static const char * const iio_modifier_names[] = {
79 [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
80 [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
81 [IIO_MOD_LIGHT_BOTH] = "both",
82 [IIO_MOD_LIGHT_IR] = "ir",
83 [IIO_MOD_LIGHT_CLEAR] = "clear",
84 [IIO_MOD_LIGHT_RED] = "red",
85 [IIO_MOD_LIGHT_GREEN] = "green",
86 [IIO_MOD_LIGHT_BLUE] = "blue",
87 [IIO_MOD_QUATERNION] = "quaternion",
88 [IIO_MOD_TEMP_AMBIENT] = "ambient",
89 [IIO_MOD_TEMP_OBJECT] = "object",
92 /* relies on pairs of these shared then separate */
93 static const char * const iio_chan_info_postfix[] = {
94 [IIO_CHAN_INFO_RAW] = "raw",
95 [IIO_CHAN_INFO_PROCESSED] = "input",
96 [IIO_CHAN_INFO_SCALE] = "scale",
97 [IIO_CHAN_INFO_OFFSET] = "offset",
98 [IIO_CHAN_INFO_CALIBSCALE] = "calibscale",
99 [IIO_CHAN_INFO_CALIBBIAS] = "calibbias",
100 [IIO_CHAN_INFO_PEAK] = "peak_raw",
101 [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",
102 [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",
103 [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",
104 [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]
105 = "filter_low_pass_3db_frequency",
106 [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",
107 [IIO_CHAN_INFO_FREQUENCY] = "frequency",
108 [IIO_CHAN_INFO_PHASE] = "phase",
109 [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
110 [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
111 [IIO_CHAN_INFO_INT_TIME] = "integration_time",
115 * iio_find_channel_from_si() - get channel from its scan index
117 * @si: scan index to match
119 const struct iio_chan_spec
120 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si)
124 for (i = 0; i < indio_dev->num_channels; i++)
125 if (indio_dev->channels[i].scan_index == si)
126 return &indio_dev->channels[i];
130 /* This turns up an awful lot */
131 ssize_t iio_read_const_attr(struct device *dev,
132 struct device_attribute *attr,
135 return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string);
137 EXPORT_SYMBOL(iio_read_const_attr);
139 static int __init iio_init(void)
143 /* Register sysfs bus */
144 ret = bus_register(&iio_bus_type);
146 pr_err("could not register bus type\n");
150 ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");
152 pr_err("failed to allocate char dev region\n");
153 goto error_unregister_bus_type;
156 iio_debugfs_dentry = debugfs_create_dir("iio", NULL);
160 error_unregister_bus_type:
161 bus_unregister(&iio_bus_type);
166 static void __exit iio_exit(void)
169 unregister_chrdev_region(iio_devt, IIO_DEV_MAX);
170 bus_unregister(&iio_bus_type);
171 debugfs_remove(iio_debugfs_dentry);
174 #if defined(CONFIG_DEBUG_FS)
175 static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
176 size_t count, loff_t *ppos)
178 struct iio_dev *indio_dev = file->private_data;
184 ret = indio_dev->info->debugfs_reg_access(indio_dev,
185 indio_dev->cached_reg_addr,
188 dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
190 len = snprintf(buf, sizeof(buf), "0x%X\n", val);
192 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
195 static ssize_t iio_debugfs_write_reg(struct file *file,
196 const char __user *userbuf, size_t count, loff_t *ppos)
198 struct iio_dev *indio_dev = file->private_data;
203 count = min_t(size_t, count, (sizeof(buf)-1));
204 if (copy_from_user(buf, userbuf, count))
209 ret = sscanf(buf, "%i %i", ®, &val);
213 indio_dev->cached_reg_addr = reg;
216 indio_dev->cached_reg_addr = reg;
217 ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,
220 dev_err(indio_dev->dev.parent, "%s: write failed\n",
232 static const struct file_operations iio_debugfs_reg_fops = {
234 .read = iio_debugfs_read_reg,
235 .write = iio_debugfs_write_reg,
238 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
240 debugfs_remove_recursive(indio_dev->debugfs_dentry);
243 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
247 if (indio_dev->info->debugfs_reg_access == NULL)
250 if (!iio_debugfs_dentry)
253 indio_dev->debugfs_dentry =
254 debugfs_create_dir(dev_name(&indio_dev->dev),
256 if (indio_dev->debugfs_dentry == NULL) {
257 dev_warn(indio_dev->dev.parent,
258 "Failed to create debugfs directory\n");
262 d = debugfs_create_file("direct_reg_access", 0644,
263 indio_dev->debugfs_dentry,
264 indio_dev, &iio_debugfs_reg_fops);
266 iio_device_unregister_debugfs(indio_dev);
273 static int iio_device_register_debugfs(struct iio_dev *indio_dev)
278 static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)
281 #endif /* CONFIG_DEBUG_FS */
283 static ssize_t iio_read_channel_ext_info(struct device *dev,
284 struct device_attribute *attr,
287 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
288 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
289 const struct iio_chan_spec_ext_info *ext_info;
291 ext_info = &this_attr->c->ext_info[this_attr->address];
293 return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);
296 static ssize_t iio_write_channel_ext_info(struct device *dev,
297 struct device_attribute *attr,
301 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
302 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
303 const struct iio_chan_spec_ext_info *ext_info;
305 ext_info = &this_attr->c->ext_info[this_attr->address];
307 return ext_info->write(indio_dev, ext_info->private,
308 this_attr->c, buf, len);
311 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
312 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
314 const struct iio_enum *e = (const struct iio_enum *)priv;
321 for (i = 0; i < e->num_items; ++i)
322 len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
324 /* replace last space with a newline */
329 EXPORT_SYMBOL_GPL(iio_enum_available_read);
331 ssize_t iio_enum_read(struct iio_dev *indio_dev,
332 uintptr_t priv, const struct iio_chan_spec *chan, char *buf)
334 const struct iio_enum *e = (const struct iio_enum *)priv;
340 i = e->get(indio_dev, chan);
343 else if (i >= e->num_items)
346 return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
348 EXPORT_SYMBOL_GPL(iio_enum_read);
350 ssize_t iio_enum_write(struct iio_dev *indio_dev,
351 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
354 const struct iio_enum *e = (const struct iio_enum *)priv;
361 for (i = 0; i < e->num_items; i++) {
362 if (sysfs_streq(buf, e->items[i]))
366 if (i == e->num_items)
369 ret = e->set(indio_dev, chan, i);
370 return ret ? ret : len;
372 EXPORT_SYMBOL_GPL(iio_enum_write);
375 * iio_format_value() - Formats a IIO value into its string representation
376 * @buf: The buffer to which the formated value gets written
377 * @type: One of the IIO_VAL_... constants. This decides how the val and val2
378 * parameters are formatted.
379 * @vals: pointer to the values, exact meaning depends on the type parameter.
381 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)
383 unsigned long long tmp;
384 bool scale_db = false;
388 return sprintf(buf, "%d\n", vals[0]);
389 case IIO_VAL_INT_PLUS_MICRO_DB:
391 case IIO_VAL_INT_PLUS_MICRO:
393 return sprintf(buf, "-%ld.%06u%s\n", abs(vals[0]),
395 scale_db ? " dB" : "");
397 return sprintf(buf, "%d.%06u%s\n", vals[0], vals[1],
398 scale_db ? " dB" : "");
399 case IIO_VAL_INT_PLUS_NANO:
401 return sprintf(buf, "-%ld.%09u\n", abs(vals[0]),
404 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
405 case IIO_VAL_FRACTIONAL:
406 tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
407 vals[1] = do_div(tmp, 1000000000LL);
409 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
410 case IIO_VAL_FRACTIONAL_LOG2:
411 tmp = (s64)vals[0] * 1000000000LL >> vals[1];
412 vals[1] = do_div(tmp, 1000000000LL);
414 return sprintf(buf, "%d.%09u\n", vals[0], vals[1]);
415 case IIO_VAL_INT_MULTIPLE:
420 for (i = 0; i < size; ++i)
421 len += snprintf(&buf[len], PAGE_SIZE - len, "%d ",
423 len += snprintf(&buf[len], PAGE_SIZE - len, "\n");
431 static ssize_t iio_read_channel_info(struct device *dev,
432 struct device_attribute *attr,
435 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
436 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
437 int vals[INDIO_MAX_RAW_ELEMENTS];
441 if (indio_dev->info->read_raw_multi)
442 ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,
443 INDIO_MAX_RAW_ELEMENTS,
447 ret = indio_dev->info->read_raw(indio_dev, this_attr->c,
448 &vals[0], &vals[1], this_attr->address);
453 return iio_format_value(buf, ret, val_len, vals);
457 * iio_str_to_fixpoint() - Parse a fixed-point number from a string
458 * @str: The string to parse
459 * @fract_mult: Multiplier for the first decimal place, should be a power of 10
460 * @integer: The integer part of the number
461 * @fract: The fractional part of the number
463 * Returns 0 on success, or a negative error code if the string could not be
466 int iio_str_to_fixpoint(const char *str, int fract_mult,
467 int *integer, int *fract)
470 bool integer_part = true, negative = false;
475 } else if (str[0] == '+') {
480 if ('0' <= *str && *str <= '9') {
482 i = i * 10 + *str - '0';
484 f += fract_mult * (*str - '0');
487 } else if (*str == '\n') {
488 if (*(str + 1) == '\0')
492 } else if (*str == '.' && integer_part) {
493 integer_part = false;
512 EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
514 static ssize_t iio_write_channel_info(struct device *dev,
515 struct device_attribute *attr,
519 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
520 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
521 int ret, fract_mult = 100000;
524 /* Assumes decimal - precision based on number of digits */
525 if (!indio_dev->info->write_raw)
528 if (indio_dev->info->write_raw_get_fmt)
529 switch (indio_dev->info->write_raw_get_fmt(indio_dev,
530 this_attr->c, this_attr->address)) {
531 case IIO_VAL_INT_PLUS_MICRO:
534 case IIO_VAL_INT_PLUS_NANO:
535 fract_mult = 100000000;
541 ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
545 ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
546 integer, fract, this_attr->address);
554 int __iio_device_attr_init(struct device_attribute *dev_attr,
556 struct iio_chan_spec const *chan,
557 ssize_t (*readfunc)(struct device *dev,
558 struct device_attribute *attr,
560 ssize_t (*writefunc)(struct device *dev,
561 struct device_attribute *attr,
564 enum iio_shared_by shared_by)
569 sysfs_attr_init(&dev_attr->attr);
571 /* Build up postfix of <extend_name>_<modifier>_postfix */
572 if (chan->modified && (shared_by == IIO_SEPARATE)) {
573 if (chan->extend_name)
574 full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
575 iio_modifier_names[chan
580 full_postfix = kasprintf(GFP_KERNEL, "%s_%s",
581 iio_modifier_names[chan
585 if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)
586 full_postfix = kstrdup(postfix, GFP_KERNEL);
588 full_postfix = kasprintf(GFP_KERNEL,
593 if (full_postfix == NULL)
596 if (chan->differential) { /* Differential can not have modifier */
598 case IIO_SHARED_BY_ALL:
599 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
601 case IIO_SHARED_BY_DIR:
602 name = kasprintf(GFP_KERNEL, "%s_%s",
603 iio_direction[chan->output],
606 case IIO_SHARED_BY_TYPE:
607 name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
608 iio_direction[chan->output],
609 iio_chan_type_name_spec[chan->type],
610 iio_chan_type_name_spec[chan->type],
614 if (!chan->indexed) {
615 WARN_ON("Differential channels must be indexed\n");
617 goto error_free_full_postfix;
619 name = kasprintf(GFP_KERNEL,
621 iio_direction[chan->output],
622 iio_chan_type_name_spec[chan->type],
624 iio_chan_type_name_spec[chan->type],
629 } else { /* Single ended */
631 case IIO_SHARED_BY_ALL:
632 name = kasprintf(GFP_KERNEL, "%s", full_postfix);
634 case IIO_SHARED_BY_DIR:
635 name = kasprintf(GFP_KERNEL, "%s_%s",
636 iio_direction[chan->output],
639 case IIO_SHARED_BY_TYPE:
640 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
641 iio_direction[chan->output],
642 iio_chan_type_name_spec[chan->type],
648 name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
649 iio_direction[chan->output],
650 iio_chan_type_name_spec[chan->type],
654 name = kasprintf(GFP_KERNEL, "%s_%s_%s",
655 iio_direction[chan->output],
656 iio_chan_type_name_spec[chan->type],
663 goto error_free_full_postfix;
665 dev_attr->attr.name = name;
668 dev_attr->attr.mode |= S_IRUGO;
669 dev_attr->show = readfunc;
673 dev_attr->attr.mode |= S_IWUSR;
674 dev_attr->store = writefunc;
677 error_free_full_postfix:
683 static void __iio_device_attr_deinit(struct device_attribute *dev_attr)
685 kfree(dev_attr->attr.name);
688 int __iio_add_chan_devattr(const char *postfix,
689 struct iio_chan_spec const *chan,
690 ssize_t (*readfunc)(struct device *dev,
691 struct device_attribute *attr,
693 ssize_t (*writefunc)(struct device *dev,
694 struct device_attribute *attr,
698 enum iio_shared_by shared_by,
700 struct list_head *attr_list)
703 struct iio_dev_attr *iio_attr, *t;
705 iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);
706 if (iio_attr == NULL)
708 ret = __iio_device_attr_init(&iio_attr->dev_attr,
710 readfunc, writefunc, shared_by);
712 goto error_iio_dev_attr_free;
714 iio_attr->address = mask;
715 list_for_each_entry(t, attr_list, l)
716 if (strcmp(t->dev_attr.attr.name,
717 iio_attr->dev_attr.attr.name) == 0) {
718 if (shared_by == IIO_SEPARATE)
719 dev_err(dev, "tried to double register : %s\n",
720 t->dev_attr.attr.name);
722 goto error_device_attr_deinit;
724 list_add(&iio_attr->l, attr_list);
728 error_device_attr_deinit:
729 __iio_device_attr_deinit(&iio_attr->dev_attr);
730 error_iio_dev_attr_free:
735 static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
736 struct iio_chan_spec const *chan,
737 enum iio_shared_by shared_by,
738 const long *infomask)
740 int i, ret, attrcount = 0;
742 for_each_set_bit(i, infomask, sizeof(infomask)*8) {
743 if (i >= ARRAY_SIZE(iio_chan_info_postfix))
745 ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
747 &iio_read_channel_info,
748 &iio_write_channel_info,
752 &indio_dev->channel_attr_list);
753 if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
763 static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,
764 struct iio_chan_spec const *chan)
766 int ret, attrcount = 0;
767 const struct iio_chan_spec_ext_info *ext_info;
769 if (chan->channel < 0)
771 ret = iio_device_add_info_mask_type(indio_dev, chan,
773 &chan->info_mask_separate);
778 ret = iio_device_add_info_mask_type(indio_dev, chan,
780 &chan->info_mask_shared_by_type);
785 ret = iio_device_add_info_mask_type(indio_dev, chan,
787 &chan->info_mask_shared_by_dir);
792 ret = iio_device_add_info_mask_type(indio_dev, chan,
794 &chan->info_mask_shared_by_all);
799 if (chan->ext_info) {
801 for (ext_info = chan->ext_info; ext_info->name; ext_info++) {
802 ret = __iio_add_chan_devattr(ext_info->name,
805 &iio_read_channel_ext_info : NULL,
807 &iio_write_channel_ext_info : NULL,
811 &indio_dev->channel_attr_list);
813 if (ret == -EBUSY && ext_info->shared)
827 * iio_free_chan_devattr_list() - Free a list of IIO device attributes
828 * @attr_list: List of IIO device attributes
830 * This function frees the memory allocated for each of the IIO device
831 * attributes in the list. Note: if you want to reuse the list after calling
832 * this function you have to reinitialize it using INIT_LIST_HEAD().
834 void iio_free_chan_devattr_list(struct list_head *attr_list)
836 struct iio_dev_attr *p, *n;
838 list_for_each_entry_safe(p, n, attr_list, l) {
839 kfree(p->dev_attr.attr.name);
844 static ssize_t iio_show_dev_name(struct device *dev,
845 struct device_attribute *attr,
848 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
849 return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name);
852 static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL);
854 static int iio_device_register_sysfs(struct iio_dev *indio_dev)
856 int i, ret = 0, attrcount, attrn, attrcount_orig = 0;
857 struct iio_dev_attr *p;
858 struct attribute **attr;
860 /* First count elements in any existing group */
861 if (indio_dev->info->attrs) {
862 attr = indio_dev->info->attrs->attrs;
863 while (*attr++ != NULL)
866 attrcount = attrcount_orig;
868 * New channel registration method - relies on the fact a group does
869 * not need to be initialized if its name is NULL.
871 if (indio_dev->channels)
872 for (i = 0; i < indio_dev->num_channels; i++) {
873 ret = iio_device_add_channel_sysfs(indio_dev,
877 goto error_clear_attrs;
884 indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1,
885 sizeof(indio_dev->chan_attr_group.attrs[0]),
887 if (indio_dev->chan_attr_group.attrs == NULL) {
889 goto error_clear_attrs;
891 /* Copy across original attributes */
892 if (indio_dev->info->attrs)
893 memcpy(indio_dev->chan_attr_group.attrs,
894 indio_dev->info->attrs->attrs,
895 sizeof(indio_dev->chan_attr_group.attrs[0])
897 attrn = attrcount_orig;
898 /* Add all elements from the list. */
899 list_for_each_entry(p, &indio_dev->channel_attr_list, l)
900 indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;
902 indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;
904 indio_dev->groups[indio_dev->groupcounter++] =
905 &indio_dev->chan_attr_group;
910 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
915 static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)
918 iio_free_chan_devattr_list(&indio_dev->channel_attr_list);
919 kfree(indio_dev->chan_attr_group.attrs);
922 static void iio_dev_release(struct device *device)
924 struct iio_dev *indio_dev = dev_to_iio_dev(device);
925 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
926 iio_device_unregister_trigger_consumer(indio_dev);
927 iio_device_unregister_eventset(indio_dev);
928 iio_device_unregister_sysfs(indio_dev);
930 iio_buffer_put(indio_dev->buffer);
932 ida_simple_remove(&iio_ida, indio_dev->id);
936 struct device_type iio_device_type = {
937 .name = "iio_device",
938 .release = iio_dev_release,
942 * iio_device_alloc() - allocate an iio_dev from a driver
943 * @sizeof_priv: Space to allocate for private structure.
945 struct iio_dev *iio_device_alloc(int sizeof_priv)
950 alloc_size = sizeof(struct iio_dev);
952 alloc_size = ALIGN(alloc_size, IIO_ALIGN);
953 alloc_size += sizeof_priv;
955 /* ensure 32-byte alignment of whole construct ? */
956 alloc_size += IIO_ALIGN - 1;
958 dev = kzalloc(alloc_size, GFP_KERNEL);
961 dev->dev.groups = dev->groups;
962 dev->dev.type = &iio_device_type;
963 dev->dev.bus = &iio_bus_type;
964 device_initialize(&dev->dev);
965 dev_set_drvdata(&dev->dev, (void *)dev);
966 mutex_init(&dev->mlock);
967 mutex_init(&dev->info_exist_lock);
968 INIT_LIST_HEAD(&dev->channel_attr_list);
970 dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
972 /* cannot use a dev_err as the name isn't available */
973 pr_err("failed to get device id\n");
977 dev_set_name(&dev->dev, "iio:device%d", dev->id);
978 INIT_LIST_HEAD(&dev->buffer_list);
983 EXPORT_SYMBOL(iio_device_alloc);
986 * iio_device_free() - free an iio_dev from a driver
987 * @dev: the iio_dev associated with the device
989 void iio_device_free(struct iio_dev *dev)
992 put_device(&dev->dev);
994 EXPORT_SYMBOL(iio_device_free);
996 static void devm_iio_device_release(struct device *dev, void *res)
998 iio_device_free(*(struct iio_dev **)res);
1001 static int devm_iio_device_match(struct device *dev, void *res, void *data)
1003 struct iio_dev **r = res;
1012 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
1013 * @dev: Device to allocate iio_dev for
1014 * @sizeof_priv: Space to allocate for private structure.
1016 * Managed iio_device_alloc. iio_dev allocated with this function is
1017 * automatically freed on driver detach.
1019 * If an iio_dev allocated with this function needs to be freed separately,
1020 * devm_iio_device_free() must be used.
1023 * Pointer to allocated iio_dev on success, NULL on failure.
1025 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv)
1027 struct iio_dev **ptr, *iio_dev;
1029 ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr),
1034 /* use raw alloc_dr for kmalloc caller tracing */
1035 iio_dev = iio_device_alloc(sizeof_priv);
1038 devres_add(dev, ptr);
1045 EXPORT_SYMBOL_GPL(devm_iio_device_alloc);
1048 * devm_iio_device_free - Resource-managed iio_device_free()
1049 * @dev: Device this iio_dev belongs to
1050 * @iio_dev: the iio_dev associated with the device
1052 * Free iio_dev allocated with devm_iio_device_alloc().
1054 void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev)
1058 rc = devres_release(dev, devm_iio_device_release,
1059 devm_iio_device_match, iio_dev);
1062 EXPORT_SYMBOL_GPL(devm_iio_device_free);
1065 * iio_chrdev_open() - chrdev file open for buffer access and ioctls
1067 static int iio_chrdev_open(struct inode *inode, struct file *filp)
1069 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1070 struct iio_dev, chrdev);
1072 if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags))
1075 iio_device_get(indio_dev);
1077 filp->private_data = indio_dev;
1083 * iio_chrdev_release() - chrdev file close buffer access and ioctls
1085 static int iio_chrdev_release(struct inode *inode, struct file *filp)
1087 struct iio_dev *indio_dev = container_of(inode->i_cdev,
1088 struct iio_dev, chrdev);
1089 clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags);
1090 iio_device_put(indio_dev);
1095 /* Somewhat of a cross file organization violation - ioctls here are actually
1097 static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1099 struct iio_dev *indio_dev = filp->private_data;
1100 int __user *ip = (int __user *)arg;
1103 if (!indio_dev->info)
1106 if (cmd == IIO_GET_EVENT_FD_IOCTL) {
1107 fd = iio_event_getfd(indio_dev);
1108 if (copy_to_user(ip, &fd, sizeof(fd)))
1115 static const struct file_operations iio_buffer_fileops = {
1116 .read = iio_buffer_read_first_n_outer_addr,
1117 .release = iio_chrdev_release,
1118 .open = iio_chrdev_open,
1119 .poll = iio_buffer_poll_addr,
1120 .owner = THIS_MODULE,
1121 .llseek = noop_llseek,
1122 .unlocked_ioctl = iio_ioctl,
1123 .compat_ioctl = iio_ioctl,
1126 static const struct iio_buffer_setup_ops noop_ring_setup_ops;
1129 * iio_device_register() - register a device with the IIO subsystem
1130 * @indio_dev: Device structure filled by the device driver
1132 int iio_device_register(struct iio_dev *indio_dev)
1136 /* If the calling driver did not initialize of_node, do it here */
1137 if (!indio_dev->dev.of_node && indio_dev->dev.parent)
1138 indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
1140 /* configure elements for the chrdev */
1141 indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id);
1143 ret = iio_device_register_debugfs(indio_dev);
1145 dev_err(indio_dev->dev.parent,
1146 "Failed to register debugfs interfaces\n");
1149 ret = iio_device_register_sysfs(indio_dev);
1151 dev_err(indio_dev->dev.parent,
1152 "Failed to register sysfs interfaces\n");
1153 goto error_unreg_debugfs;
1155 ret = iio_device_register_eventset(indio_dev);
1157 dev_err(indio_dev->dev.parent,
1158 "Failed to register event set\n");
1159 goto error_free_sysfs;
1161 if (indio_dev->modes & INDIO_BUFFER_TRIGGERED)
1162 iio_device_register_trigger_consumer(indio_dev);
1164 if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&
1165 indio_dev->setup_ops == NULL)
1166 indio_dev->setup_ops = &noop_ring_setup_ops;
1168 cdev_init(&indio_dev->chrdev, &iio_buffer_fileops);
1169 indio_dev->chrdev.owner = indio_dev->info->driver_module;
1170 indio_dev->chrdev.kobj.parent = &indio_dev->dev.kobj;
1171 ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1);
1173 goto error_unreg_eventset;
1175 ret = device_add(&indio_dev->dev);
1177 goto error_cdev_del;
1181 cdev_del(&indio_dev->chrdev);
1182 error_unreg_eventset:
1183 iio_device_unregister_eventset(indio_dev);
1185 iio_device_unregister_sysfs(indio_dev);
1186 error_unreg_debugfs:
1187 iio_device_unregister_debugfs(indio_dev);
1190 EXPORT_SYMBOL(iio_device_register);
1193 * iio_device_unregister() - unregister a device from the IIO subsystem
1194 * @indio_dev: Device structure representing the device.
1196 void iio_device_unregister(struct iio_dev *indio_dev)
1198 mutex_lock(&indio_dev->info_exist_lock);
1200 device_del(&indio_dev->dev);
1202 if (indio_dev->chrdev.dev)
1203 cdev_del(&indio_dev->chrdev);
1204 iio_device_unregister_debugfs(indio_dev);
1206 iio_disable_all_buffers(indio_dev);
1208 indio_dev->info = NULL;
1210 iio_device_wakeup_eventset(indio_dev);
1211 iio_buffer_wakeup_poll(indio_dev);
1213 mutex_unlock(&indio_dev->info_exist_lock);
1215 EXPORT_SYMBOL(iio_device_unregister);
1217 static void devm_iio_device_unreg(struct device *dev, void *res)
1219 iio_device_unregister(*(struct iio_dev **)res);
1223 * devm_iio_device_register - Resource-managed iio_device_register()
1224 * @dev: Device to allocate iio_dev for
1225 * @indio_dev: Device structure filled by the device driver
1227 * Managed iio_device_register. The IIO device registered with this
1228 * function is automatically unregistered on driver detach. This function
1229 * calls iio_device_register() internally. Refer to that function for more
1232 * If an iio_dev registered with this function needs to be unregistered
1233 * separately, devm_iio_device_unregister() must be used.
1236 * 0 on success, negative error number on failure.
1238 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev)
1240 struct iio_dev **ptr;
1243 ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL);
1248 ret = iio_device_register(indio_dev);
1250 devres_add(dev, ptr);
1256 EXPORT_SYMBOL_GPL(devm_iio_device_register);
1259 * devm_iio_device_unregister - Resource-managed iio_device_unregister()
1260 * @dev: Device this iio_dev belongs to
1261 * @indio_dev: the iio_dev associated with the device
1263 * Unregister iio_dev registered with devm_iio_device_register().
1265 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev)
1269 rc = devres_release(dev, devm_iio_device_unreg,
1270 devm_iio_device_match, indio_dev);
1273 EXPORT_SYMBOL_GPL(devm_iio_device_unregister);
1275 subsys_initcall(iio_init);
1276 module_exit(iio_exit);
1278 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
1279 MODULE_DESCRIPTION("Industrial I/O core");
1280 MODULE_LICENSE("GPL");