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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * The industrial I/O core4 *5 * Copyright (c) 2008 Jonathan Cameron6 *7 * Based on elements of hwmon and input subsystems.8 */9 10#define pr_fmt(fmt) "iio-core: " fmt11 12#include <linux/anon_inodes.h>13#include <linux/cdev.h>14#include <linux/cleanup.h>15#include <linux/debugfs.h>16#include <linux/device.h>17#include <linux/err.h>18#include <linux/fs.h>19#include <linux/idr.h>20#include <linux/kdev_t.h>21#include <linux/kernel.h>22#include <linux/module.h>23#include <linux/mutex.h>24#include <linux/poll.h>25#include <linux/property.h>26#include <linux/sched.h>27#include <linux/slab.h>28#include <linux/wait.h>29 30#include <linux/iio/buffer.h>31#include <linux/iio/buffer_impl.h>32#include <linux/iio/events.h>33#include <linux/iio/iio-opaque.h>34#include <linux/iio/iio.h>35#include <linux/iio/sysfs.h>36 37#include "iio_core.h"38#include "iio_core_trigger.h"39 40/* IDA to assign each registered device a unique id */41static DEFINE_IDA(iio_ida);42 43static dev_t iio_devt;44 45#define IIO_DEV_MAX 25646const struct bus_type iio_bus_type = {47	.name = "iio",48};49EXPORT_SYMBOL(iio_bus_type);50 51static struct dentry *iio_debugfs_dentry;52 53static const char * const iio_direction[] = {54	[0] = "in",55	[1] = "out",56};57 58static const char * const iio_chan_type_name_spec[] = {59	[IIO_VOLTAGE] = "voltage",60	[IIO_CURRENT] = "current",61	[IIO_POWER] = "power",62	[IIO_ACCEL] = "accel",63	[IIO_ANGL_VEL] = "anglvel",64	[IIO_MAGN] = "magn",65	[IIO_LIGHT] = "illuminance",66	[IIO_INTENSITY] = "intensity",67	[IIO_PROXIMITY] = "proximity",68	[IIO_TEMP] = "temp",69	[IIO_INCLI] = "incli",70	[IIO_ROT] = "rot",71	[IIO_ANGL] = "angl",72	[IIO_TIMESTAMP] = "timestamp",73	[IIO_CAPACITANCE] = "capacitance",74	[IIO_ALTVOLTAGE] = "altvoltage",75	[IIO_CCT] = "cct",76	[IIO_PRESSURE] = "pressure",77	[IIO_HUMIDITYRELATIVE] = "humidityrelative",78	[IIO_ACTIVITY] = "activity",79	[IIO_STEPS] = "steps",80	[IIO_ENERGY] = "energy",81	[IIO_DISTANCE] = "distance",82	[IIO_VELOCITY] = "velocity",83	[IIO_CONCENTRATION] = "concentration",84	[IIO_RESISTANCE] = "resistance",85	[IIO_PH] = "ph",86	[IIO_UVINDEX] = "uvindex",87	[IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",88	[IIO_COUNT] = "count",89	[IIO_INDEX] = "index",90	[IIO_GRAVITY]  = "gravity",91	[IIO_POSITIONRELATIVE]  = "positionrelative",92	[IIO_PHASE] = "phase",93	[IIO_MASSCONCENTRATION] = "massconcentration",94	[IIO_DELTA_ANGL] = "deltaangl",95	[IIO_DELTA_VELOCITY] = "deltavelocity",96	[IIO_COLORTEMP] = "colortemp",97	[IIO_CHROMATICITY] = "chromaticity",98};99 100static const char * const iio_modifier_names[] = {101	[IIO_MOD_X] = "x",102	[IIO_MOD_Y] = "y",103	[IIO_MOD_Z] = "z",104	[IIO_MOD_X_AND_Y] = "x&y",105	[IIO_MOD_X_AND_Z] = "x&z",106	[IIO_MOD_Y_AND_Z] = "y&z",107	[IIO_MOD_X_AND_Y_AND_Z] = "x&y&z",108	[IIO_MOD_X_OR_Y] = "x|y",109	[IIO_MOD_X_OR_Z] = "x|z",110	[IIO_MOD_Y_OR_Z] = "y|z",111	[IIO_MOD_X_OR_Y_OR_Z] = "x|y|z",112	[IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",113	[IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",114	[IIO_MOD_LIGHT_BOTH] = "both",115	[IIO_MOD_LIGHT_IR] = "ir",116	[IIO_MOD_LIGHT_CLEAR] = "clear",117	[IIO_MOD_LIGHT_RED] = "red",118	[IIO_MOD_LIGHT_GREEN] = "green",119	[IIO_MOD_LIGHT_BLUE] = "blue",120	[IIO_MOD_LIGHT_UV] = "uv",121	[IIO_MOD_LIGHT_UVA] = "uva",122	[IIO_MOD_LIGHT_UVB] = "uvb",123	[IIO_MOD_LIGHT_DUV] = "duv",124	[IIO_MOD_QUATERNION] = "quaternion",125	[IIO_MOD_TEMP_AMBIENT] = "ambient",126	[IIO_MOD_TEMP_OBJECT] = "object",127	[IIO_MOD_NORTH_MAGN] = "from_north_magnetic",128	[IIO_MOD_NORTH_TRUE] = "from_north_true",129	[IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",130	[IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",131	[IIO_MOD_RUNNING] = "running",132	[IIO_MOD_JOGGING] = "jogging",133	[IIO_MOD_WALKING] = "walking",134	[IIO_MOD_STILL] = "still",135	[IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",136	[IIO_MOD_I] = "i",137	[IIO_MOD_Q] = "q",138	[IIO_MOD_CO2] = "co2",139	[IIO_MOD_VOC] = "voc",140	[IIO_MOD_PM1] = "pm1",141	[IIO_MOD_PM2P5] = "pm2p5",142	[IIO_MOD_PM4] = "pm4",143	[IIO_MOD_PM10] = "pm10",144	[IIO_MOD_ETHANOL] = "ethanol",145	[IIO_MOD_H2] = "h2",146	[IIO_MOD_O2] = "o2",147	[IIO_MOD_LINEAR_X] = "linear_x",148	[IIO_MOD_LINEAR_Y] = "linear_y",149	[IIO_MOD_LINEAR_Z] = "linear_z",150	[IIO_MOD_PITCH] = "pitch",151	[IIO_MOD_YAW] = "yaw",152	[IIO_MOD_ROLL] = "roll",153};154 155/* relies on pairs of these shared then separate */156static const char * const iio_chan_info_postfix[] = {157	[IIO_CHAN_INFO_RAW] = "raw",158	[IIO_CHAN_INFO_PROCESSED] = "input",159	[IIO_CHAN_INFO_SCALE] = "scale",160	[IIO_CHAN_INFO_OFFSET] = "offset",161	[IIO_CHAN_INFO_CALIBSCALE] = "calibscale",162	[IIO_CHAN_INFO_CALIBBIAS] = "calibbias",163	[IIO_CHAN_INFO_PEAK] = "peak_raw",164	[IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale",165	[IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw",166	[IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw",167	[IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY]168	= "filter_low_pass_3db_frequency",169	[IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY]170	= "filter_high_pass_3db_frequency",171	[IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency",172	[IIO_CHAN_INFO_FREQUENCY] = "frequency",173	[IIO_CHAN_INFO_PHASE] = "phase",174	[IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",175	[IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",176	[IIO_CHAN_INFO_HYSTERESIS_RELATIVE] = "hysteresis_relative",177	[IIO_CHAN_INFO_INT_TIME] = "integration_time",178	[IIO_CHAN_INFO_ENABLE] = "en",179	[IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",180	[IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",181	[IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count",182	[IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time",183	[IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity",184	[IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio",185	[IIO_CHAN_INFO_THERMOCOUPLE_TYPE] = "thermocouple_type",186	[IIO_CHAN_INFO_CALIBAMBIENT] = "calibambient",187	[IIO_CHAN_INFO_ZEROPOINT] = "zeropoint",188	[IIO_CHAN_INFO_TROUGH] = "trough_raw",189};190/**191 * iio_device_id() - query the unique ID for the device192 * @indio_dev:		Device structure whose ID is being queried193 *194 * The IIO device ID is a unique index used for example for the naming195 * of the character device /dev/iio\:device[ID].196 *197 * Returns: Unique ID for the device.198 */199int iio_device_id(struct iio_dev *indio_dev)200{201	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);202 203	return iio_dev_opaque->id;204}205EXPORT_SYMBOL_GPL(iio_device_id);206 207/**208 * iio_buffer_enabled() - helper function to test if the buffer is enabled209 * @indio_dev:		IIO device structure for device210 *211 * Returns: True, if the buffer is enabled.212 */213bool iio_buffer_enabled(struct iio_dev *indio_dev)214{215	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);216 217	return iio_dev_opaque->currentmode & INDIO_ALL_BUFFER_MODES;218}219EXPORT_SYMBOL_GPL(iio_buffer_enabled);220 221#if defined(CONFIG_DEBUG_FS)222/*223 * There's also a CONFIG_DEBUG_FS guard in include/linux/iio/iio.h for224 * iio_get_debugfs_dentry() to make it inline if CONFIG_DEBUG_FS is undefined225 */226struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)227{228	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);229 230	return iio_dev_opaque->debugfs_dentry;231}232EXPORT_SYMBOL_GPL(iio_get_debugfs_dentry);233#endif234 235/**236 * iio_find_channel_from_si() - get channel from its scan index237 * @indio_dev:		device238 * @si:			scan index to match239 *240 * Returns:241 * Constant pointer to iio_chan_spec, if scan index matches, NULL on failure.242 */243const struct iio_chan_spec244*iio_find_channel_from_si(struct iio_dev *indio_dev, int si)245{246	int i;247 248	for (i = 0; i < indio_dev->num_channels; i++)249		if (indio_dev->channels[i].scan_index == si)250			return &indio_dev->channels[i];251	return NULL;252}253 254/* This turns up an awful lot */255ssize_t iio_read_const_attr(struct device *dev,256			    struct device_attribute *attr,257			    char *buf)258{259	return sysfs_emit(buf, "%s\n", to_iio_const_attr(attr)->string);260}261EXPORT_SYMBOL(iio_read_const_attr);262 263/**264 * iio_device_set_clock() - Set current timestamping clock for the device265 * @indio_dev: IIO device structure containing the device266 * @clock_id: timestamping clock POSIX identifier to set.267 *268 * Returns: 0 on success, or a negative error code.269 */270int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id)271{272	int ret;273	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);274	const struct iio_event_interface *ev_int = iio_dev_opaque->event_interface;275 276	ret = mutex_lock_interruptible(&iio_dev_opaque->mlock);277	if (ret)278		return ret;279	if ((ev_int && iio_event_enabled(ev_int)) ||280	    iio_buffer_enabled(indio_dev)) {281		mutex_unlock(&iio_dev_opaque->mlock);282		return -EBUSY;283	}284	iio_dev_opaque->clock_id = clock_id;285	mutex_unlock(&iio_dev_opaque->mlock);286 287	return 0;288}289EXPORT_SYMBOL(iio_device_set_clock);290 291/**292 * iio_device_get_clock() - Retrieve current timestamping clock for the device293 * @indio_dev: IIO device structure containing the device294 *295 * Returns: Clock ID of the current timestamping clock for the device.296 */297clockid_t iio_device_get_clock(const struct iio_dev *indio_dev)298{299	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);300 301	return iio_dev_opaque->clock_id;302}303EXPORT_SYMBOL(iio_device_get_clock);304 305/**306 * iio_get_time_ns() - utility function to get a time stamp for events etc307 * @indio_dev: device308 *309 * Returns: Timestamp of the event in nanoseconds.310 */311s64 iio_get_time_ns(const struct iio_dev *indio_dev)312{313	struct timespec64 tp;314 315	switch (iio_device_get_clock(indio_dev)) {316	case CLOCK_REALTIME:317		return ktime_get_real_ns();318	case CLOCK_MONOTONIC:319		return ktime_get_ns();320	case CLOCK_MONOTONIC_RAW:321		return ktime_get_raw_ns();322	case CLOCK_REALTIME_COARSE:323		return ktime_to_ns(ktime_get_coarse_real());324	case CLOCK_MONOTONIC_COARSE:325		ktime_get_coarse_ts64(&tp);326		return timespec64_to_ns(&tp);327	case CLOCK_BOOTTIME:328		return ktime_get_boottime_ns();329	case CLOCK_TAI:330		return ktime_get_clocktai_ns();331	default:332		BUG();333	}334}335EXPORT_SYMBOL(iio_get_time_ns);336 337static int __init iio_init(void)338{339	int ret;340 341	/* Register sysfs bus */342	ret  = bus_register(&iio_bus_type);343	if (ret < 0) {344		pr_err("could not register bus type\n");345		goto error_nothing;346	}347 348	ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio");349	if (ret < 0) {350		pr_err("failed to allocate char dev region\n");351		goto error_unregister_bus_type;352	}353 354	iio_debugfs_dentry = debugfs_create_dir("iio", NULL);355 356	return 0;357 358error_unregister_bus_type:359	bus_unregister(&iio_bus_type);360error_nothing:361	return ret;362}363 364static void __exit iio_exit(void)365{366	if (iio_devt)367		unregister_chrdev_region(iio_devt, IIO_DEV_MAX);368	bus_unregister(&iio_bus_type);369	debugfs_remove(iio_debugfs_dentry);370}371 372#if defined(CONFIG_DEBUG_FS)373static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,374			      size_t count, loff_t *ppos)375{376	struct iio_dev *indio_dev = file->private_data;377	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);378	unsigned int val = 0;379	int ret;380 381	if (*ppos > 0)382		return simple_read_from_buffer(userbuf, count, ppos,383					       iio_dev_opaque->read_buf,384					       iio_dev_opaque->read_buf_len);385 386	ret = indio_dev->info->debugfs_reg_access(indio_dev,387						  iio_dev_opaque->cached_reg_addr,388						  0, &val);389	if (ret) {390		dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);391		return ret;392	}393 394	iio_dev_opaque->read_buf_len = snprintf(iio_dev_opaque->read_buf,395						sizeof(iio_dev_opaque->read_buf),396						"0x%X\n", val);397 398	return simple_read_from_buffer(userbuf, count, ppos,399				       iio_dev_opaque->read_buf,400				       iio_dev_opaque->read_buf_len);401}402 403static ssize_t iio_debugfs_write_reg(struct file *file,404		     const char __user *userbuf, size_t count, loff_t *ppos)405{406	struct iio_dev *indio_dev = file->private_data;407	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);408	unsigned int reg, val;409	char buf[80];410	int ret;411 412	count = min(count, sizeof(buf) - 1);413	if (copy_from_user(buf, userbuf, count))414		return -EFAULT;415 416	buf[count] = 0;417 418	ret = sscanf(buf, "%i %i", &reg, &val);419 420	switch (ret) {421	case 1:422		iio_dev_opaque->cached_reg_addr = reg;423		break;424	case 2:425		iio_dev_opaque->cached_reg_addr = reg;426		ret = indio_dev->info->debugfs_reg_access(indio_dev, reg,427							  val, NULL);428		if (ret) {429			dev_err(indio_dev->dev.parent, "%s: write failed\n",430				__func__);431			return ret;432		}433		break;434	default:435		return -EINVAL;436	}437 438	return count;439}440 441static const struct file_operations iio_debugfs_reg_fops = {442	.open = simple_open,443	.read = iio_debugfs_read_reg,444	.write = iio_debugfs_write_reg,445};446 447static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)448{449	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);450 451	debugfs_remove_recursive(iio_dev_opaque->debugfs_dentry);452}453 454static void iio_device_register_debugfs(struct iio_dev *indio_dev)455{456	struct iio_dev_opaque *iio_dev_opaque;457 458	if (indio_dev->info->debugfs_reg_access == NULL)459		return;460 461	if (!iio_debugfs_dentry)462		return;463 464	iio_dev_opaque = to_iio_dev_opaque(indio_dev);465 466	iio_dev_opaque->debugfs_dentry =467		debugfs_create_dir(dev_name(&indio_dev->dev),468				   iio_debugfs_dentry);469 470	debugfs_create_file("direct_reg_access", 0644,471			    iio_dev_opaque->debugfs_dentry, indio_dev,472			    &iio_debugfs_reg_fops);473}474#else475static void iio_device_register_debugfs(struct iio_dev *indio_dev)476{477}478 479static void iio_device_unregister_debugfs(struct iio_dev *indio_dev)480{481}482#endif /* CONFIG_DEBUG_FS */483 484static ssize_t iio_read_channel_ext_info(struct device *dev,485				     struct device_attribute *attr,486				     char *buf)487{488	struct iio_dev *indio_dev = dev_to_iio_dev(dev);489	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);490	const struct iio_chan_spec_ext_info *ext_info;491 492	ext_info = &this_attr->c->ext_info[this_attr->address];493 494	return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf);495}496 497static ssize_t iio_write_channel_ext_info(struct device *dev,498				     struct device_attribute *attr,499				     const char *buf, size_t len)500{501	struct iio_dev *indio_dev = dev_to_iio_dev(dev);502	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);503	const struct iio_chan_spec_ext_info *ext_info;504 505	ext_info = &this_attr->c->ext_info[this_attr->address];506 507	return ext_info->write(indio_dev, ext_info->private,508			       this_attr->c, buf, len);509}510 511ssize_t iio_enum_available_read(struct iio_dev *indio_dev,512	uintptr_t priv, const struct iio_chan_spec *chan, char *buf)513{514	const struct iio_enum *e = (const struct iio_enum *)priv;515	unsigned int i;516	size_t len = 0;517 518	if (!e->num_items)519		return 0;520 521	for (i = 0; i < e->num_items; ++i) {522		if (!e->items[i])523			continue;524		len += sysfs_emit_at(buf, len, "%s ", e->items[i]);525	}526 527	/* replace last space with a newline */528	buf[len - 1] = '\n';529 530	return len;531}532EXPORT_SYMBOL_GPL(iio_enum_available_read);533 534ssize_t iio_enum_read(struct iio_dev *indio_dev,535	uintptr_t priv, const struct iio_chan_spec *chan, char *buf)536{537	const struct iio_enum *e = (const struct iio_enum *)priv;538	int i;539 540	if (!e->get)541		return -EINVAL;542 543	i = e->get(indio_dev, chan);544	if (i < 0)545		return i;546	if (i >= e->num_items || !e->items[i])547		return -EINVAL;548 549	return sysfs_emit(buf, "%s\n", e->items[i]);550}551EXPORT_SYMBOL_GPL(iio_enum_read);552 553ssize_t iio_enum_write(struct iio_dev *indio_dev,554	uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,555	size_t len)556{557	const struct iio_enum *e = (const struct iio_enum *)priv;558	int ret;559 560	if (!e->set)561		return -EINVAL;562 563	ret = __sysfs_match_string(e->items, e->num_items, buf);564	if (ret < 0)565		return ret;566 567	ret = e->set(indio_dev, chan, ret);568	return ret ? ret : len;569}570EXPORT_SYMBOL_GPL(iio_enum_write);571 572static const struct iio_mount_matrix iio_mount_idmatrix = {573	.rotation = {574		"1", "0", "0",575		"0", "1", "0",576		"0", "0", "1"577	}578};579 580static int iio_setup_mount_idmatrix(const struct device *dev,581				    struct iio_mount_matrix *matrix)582{583	*matrix = iio_mount_idmatrix;584	dev_info(dev, "mounting matrix not found: using identity...\n");585	return 0;586}587 588ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,589			      const struct iio_chan_spec *chan, char *buf)590{591	const struct iio_mount_matrix *mtx;592 593	mtx = ((iio_get_mount_matrix_t *)priv)(indio_dev, chan);594	if (IS_ERR(mtx))595		return PTR_ERR(mtx);596 597	if (!mtx)598		mtx = &iio_mount_idmatrix;599 600	return sysfs_emit(buf, "%s, %s, %s; %s, %s, %s; %s, %s, %s\n",601			  mtx->rotation[0], mtx->rotation[1], mtx->rotation[2],602			  mtx->rotation[3], mtx->rotation[4], mtx->rotation[5],603			  mtx->rotation[6], mtx->rotation[7], mtx->rotation[8]);604}605EXPORT_SYMBOL_GPL(iio_show_mount_matrix);606 607/**608 * iio_read_mount_matrix() - retrieve iio device mounting matrix from609 *                           device "mount-matrix" property610 * @dev:	device the mounting matrix property is assigned to611 * @matrix:	where to store retrieved matrix612 *613 * If device is assigned no mounting matrix property, a default 3x3 identity614 * matrix will be filled in.615 *616 * Returns: 0 if success, or a negative error code on failure.617 */618int iio_read_mount_matrix(struct device *dev, struct iio_mount_matrix *matrix)619{620	size_t len = ARRAY_SIZE(iio_mount_idmatrix.rotation);621	int err;622 623	err = device_property_read_string_array(dev, "mount-matrix", matrix->rotation, len);624	if (err == len)625		return 0;626 627	if (err >= 0)628		/* Invalid number of matrix entries. */629		return -EINVAL;630 631	if (err != -EINVAL)632		/* Invalid matrix declaration format. */633		return err;634 635	/* Matrix was not declared at all: fallback to identity. */636	return iio_setup_mount_idmatrix(dev, matrix);637}638EXPORT_SYMBOL(iio_read_mount_matrix);639 640static ssize_t __iio_format_value(char *buf, size_t offset, unsigned int type,641				  int size, const int *vals)642{643	int tmp0, tmp1;644	s64 tmp2;645	bool scale_db = false;646 647	switch (type) {648	case IIO_VAL_INT:649		return sysfs_emit_at(buf, offset, "%d", vals[0]);650	case IIO_VAL_INT_PLUS_MICRO_DB:651		scale_db = true;652		fallthrough;653	case IIO_VAL_INT_PLUS_MICRO:654		if (vals[1] < 0)655			return sysfs_emit_at(buf, offset, "-%d.%06u%s",656					     abs(vals[0]), -vals[1],657					     scale_db ? " dB" : "");658		else659			return sysfs_emit_at(buf, offset, "%d.%06u%s", vals[0],660					     vals[1], scale_db ? " dB" : "");661	case IIO_VAL_INT_PLUS_NANO:662		if (vals[1] < 0)663			return sysfs_emit_at(buf, offset, "-%d.%09u",664					     abs(vals[0]), -vals[1]);665		else666			return sysfs_emit_at(buf, offset, "%d.%09u", vals[0],667					     vals[1]);668	case IIO_VAL_FRACTIONAL:669		tmp2 = div_s64((s64)vals[0] * 1000000000LL, vals[1]);670		tmp0 = (int)div_s64_rem(tmp2, 1000000000, &tmp1);671		if ((tmp2 < 0) && (tmp0 == 0))672			return sysfs_emit_at(buf, offset, "-0.%09u", abs(tmp1));673		else674			return sysfs_emit_at(buf, offset, "%d.%09u", tmp0,675					     abs(tmp1));676	case IIO_VAL_FRACTIONAL_LOG2:677		tmp2 = shift_right((s64)vals[0] * 1000000000LL, vals[1]);678		tmp0 = (int)div_s64_rem(tmp2, 1000000000LL, &tmp1);679		if (tmp0 == 0 && tmp2 < 0)680			return sysfs_emit_at(buf, offset, "-0.%09u", abs(tmp1));681		else682			return sysfs_emit_at(buf, offset, "%d.%09u", tmp0,683					     abs(tmp1));684	case IIO_VAL_INT_MULTIPLE:685	{686		int i;687		int l = 0;688 689		for (i = 0; i < size; ++i)690			l += sysfs_emit_at(buf, offset + l, "%d ", vals[i]);691		return l;692	}693	case IIO_VAL_CHAR:694		return sysfs_emit_at(buf, offset, "%c", (char)vals[0]);695	case IIO_VAL_INT_64:696		tmp2 = (s64)((((u64)vals[1]) << 32) | (u32)vals[0]);697		return sysfs_emit_at(buf, offset, "%lld", tmp2);698	default:699		return 0;700	}701}702 703/**704 * iio_format_value() - Formats a IIO value into its string representation705 * @buf:	The buffer to which the formatted value gets written706 *		which is assumed to be big enough (i.e. PAGE_SIZE).707 * @type:	One of the IIO_VAL_* constants. This decides how the val708 *		and val2 parameters are formatted.709 * @size:	Number of IIO value entries contained in vals710 * @vals:	Pointer to the values, exact meaning depends on the711 *		type parameter.712 *713 * Returns:714 * 0 by default, a negative number on failure or the total number of characters715 * written for a type that belongs to the IIO_VAL_* constant.716 */717ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals)718{719	ssize_t len;720 721	len = __iio_format_value(buf, 0, type, size, vals);722	if (len >= PAGE_SIZE - 1)723		return -EFBIG;724 725	return len + sysfs_emit_at(buf, len, "\n");726}727EXPORT_SYMBOL_GPL(iio_format_value);728 729ssize_t do_iio_read_channel_label(struct iio_dev *indio_dev,730				  const struct iio_chan_spec *c,731				  char *buf)732{733	if (indio_dev->info->read_label)734		return indio_dev->info->read_label(indio_dev, c, buf);735 736	if (c->extend_name)737		return sysfs_emit(buf, "%s\n", c->extend_name);738 739	return -EINVAL;740}741 742static ssize_t iio_read_channel_label(struct device *dev,743				      struct device_attribute *attr,744				      char *buf)745{746	return do_iio_read_channel_label(dev_to_iio_dev(dev),747					 to_iio_dev_attr(attr)->c, buf);748}749 750static ssize_t iio_read_channel_info(struct device *dev,751				     struct device_attribute *attr,752				     char *buf)753{754	struct iio_dev *indio_dev = dev_to_iio_dev(dev);755	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);756	int vals[INDIO_MAX_RAW_ELEMENTS];757	int ret;758	int val_len = 2;759 760	if (indio_dev->info->read_raw_multi)761		ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c,762							INDIO_MAX_RAW_ELEMENTS,763							vals, &val_len,764							this_attr->address);765	else if (indio_dev->info->read_raw)766		ret = indio_dev->info->read_raw(indio_dev, this_attr->c,767				    &vals[0], &vals[1], this_attr->address);768	else769		return -EINVAL;770 771	if (ret < 0)772		return ret;773 774	return iio_format_value(buf, ret, val_len, vals);775}776 777static ssize_t iio_format_list(char *buf, const int *vals, int type, int length,778			       const char *prefix, const char *suffix)779{780	ssize_t len;781	int stride;782	int i;783 784	switch (type) {785	case IIO_VAL_INT:786		stride = 1;787		break;788	default:789		stride = 2;790		break;791	}792 793	len = sysfs_emit(buf, prefix);794 795	for (i = 0; i <= length - stride; i += stride) {796		if (i != 0) {797			len += sysfs_emit_at(buf, len, " ");798			if (len >= PAGE_SIZE)799				return -EFBIG;800		}801 802		len += __iio_format_value(buf, len, type, stride, &vals[i]);803		if (len >= PAGE_SIZE)804			return -EFBIG;805	}806 807	len += sysfs_emit_at(buf, len, "%s\n", suffix);808 809	return len;810}811 812static ssize_t iio_format_avail_list(char *buf, const int *vals,813				     int type, int length)814{815 816	return iio_format_list(buf, vals, type, length, "", "");817}818 819static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)820{821	int length;822 823	/*824	 * length refers to the array size , not the number of elements.825	 * The purpose is to print the range [min , step ,max] so length should826	 * be 3 in case of int, and 6 for other types.827	 */828	switch (type) {829	case IIO_VAL_INT:830		length = 3;831		break;832	default:833		length = 6;834		break;835	}836 837	return iio_format_list(buf, vals, type, length, "[", "]");838}839 840static ssize_t iio_read_channel_info_avail(struct device *dev,841					   struct device_attribute *attr,842					   char *buf)843{844	struct iio_dev *indio_dev = dev_to_iio_dev(dev);845	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);846	const int *vals;847	int ret;848	int length;849	int type;850 851	if (!indio_dev->info->read_avail)852		return -EINVAL;853 854	ret = indio_dev->info->read_avail(indio_dev, this_attr->c,855					  &vals, &type, &length,856					  this_attr->address);857 858	if (ret < 0)859		return ret;860	switch (ret) {861	case IIO_AVAIL_LIST:862		return iio_format_avail_list(buf, vals, type, length);863	case IIO_AVAIL_RANGE:864		return iio_format_avail_range(buf, vals, type);865	default:866		return -EINVAL;867	}868}869 870/**871 * __iio_str_to_fixpoint() - Parse a fixed-point number from a string872 * @str: The string to parse873 * @fract_mult: Multiplier for the first decimal place, should be a power of 10874 * @integer: The integer part of the number875 * @fract: The fractional part of the number876 * @scale_db: True if this should parse as dB877 *878 * Returns:879 * 0 on success, or a negative error code if the string could not be parsed.880 */881static int __iio_str_to_fixpoint(const char *str, int fract_mult,882				 int *integer, int *fract, bool scale_db)883{884	int i = 0, f = 0;885	bool integer_part = true, negative = false;886 887	if (fract_mult == 0) {888		*fract = 0;889 890		return kstrtoint(str, 0, integer);891	}892 893	if (str[0] == '-') {894		negative = true;895		str++;896	} else if (str[0] == '+') {897		str++;898	}899 900	while (*str) {901		if ('0' <= *str && *str <= '9') {902			if (integer_part) {903				i = i * 10 + *str - '0';904			} else {905				f += fract_mult * (*str - '0');906				fract_mult /= 10;907			}908		} else if (*str == '\n') {909			if (*(str + 1) == '\0')910				break;911			return -EINVAL;912		} else if (!strncmp(str, " dB", sizeof(" dB") - 1) && scale_db) {913			/* Ignore the dB suffix */914			str += sizeof(" dB") - 1;915			continue;916		} else if (!strncmp(str, "dB", sizeof("dB") - 1) && scale_db) {917			/* Ignore the dB suffix */918			str += sizeof("dB") - 1;919			continue;920		} else if (*str == '.' && integer_part) {921			integer_part = false;922		} else {923			return -EINVAL;924		}925		str++;926	}927 928	if (negative) {929		if (i)930			i = -i;931		else932			f = -f;933	}934 935	*integer = i;936	*fract = f;937 938	return 0;939}940 941/**942 * iio_str_to_fixpoint() - Parse a fixed-point number from a string943 * @str: The string to parse944 * @fract_mult: Multiplier for the first decimal place, should be a power of 10945 * @integer: The integer part of the number946 * @fract: The fractional part of the number947 *948 * Returns:949 * 0 on success, or a negative error code if the string could not be parsed.950 */951int iio_str_to_fixpoint(const char *str, int fract_mult,952			int *integer, int *fract)953{954	return __iio_str_to_fixpoint(str, fract_mult, integer, fract, false);955}956EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);957 958static ssize_t iio_write_channel_info(struct device *dev,959				      struct device_attribute *attr,960				      const char *buf,961				      size_t len)962{963	struct iio_dev *indio_dev = dev_to_iio_dev(dev);964	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);965	int ret, fract_mult = 100000;966	int integer, fract = 0;967	bool is_char = false;968	bool scale_db = false;969 970	/* Assumes decimal - precision based on number of digits */971	if (!indio_dev->info->write_raw)972		return -EINVAL;973 974	if (indio_dev->info->write_raw_get_fmt)975		switch (indio_dev->info->write_raw_get_fmt(indio_dev,976			this_attr->c, this_attr->address)) {977		case IIO_VAL_INT:978			fract_mult = 0;979			break;980		case IIO_VAL_INT_PLUS_MICRO_DB:981			scale_db = true;982			fallthrough;983		case IIO_VAL_INT_PLUS_MICRO:984			fract_mult = 100000;985			break;986		case IIO_VAL_INT_PLUS_NANO:987			fract_mult = 100000000;988			break;989		case IIO_VAL_CHAR:990			is_char = true;991			break;992		default:993			return -EINVAL;994		}995 996	if (is_char) {997		char ch;998 999		if (sscanf(buf, "%c", &ch) != 1)1000			return -EINVAL;1001		integer = ch;1002	} else {1003		ret = __iio_str_to_fixpoint(buf, fract_mult, &integer, &fract,1004					    scale_db);1005		if (ret)1006			return ret;1007	}1008 1009	ret = indio_dev->info->write_raw(indio_dev, this_attr->c,1010					 integer, fract, this_attr->address);1011	if (ret)1012		return ret;1013 1014	return len;1015}1016 1017static1018int __iio_device_attr_init(struct device_attribute *dev_attr,1019			   const char *postfix,1020			   struct iio_chan_spec const *chan,1021			   ssize_t (*readfunc)(struct device *dev,1022					       struct device_attribute *attr,1023					       char *buf),1024			   ssize_t (*writefunc)(struct device *dev,1025						struct device_attribute *attr,1026						const char *buf,1027						size_t len),1028			   enum iio_shared_by shared_by)1029{1030	int ret = 0;1031	char *name = NULL;1032	char *full_postfix;1033 1034	sysfs_attr_init(&dev_attr->attr);1035 1036	/* Build up postfix of <extend_name>_<modifier>_postfix */1037	if (chan->modified && (shared_by == IIO_SEPARATE)) {1038		if (chan->extend_name)1039			full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",1040						 iio_modifier_names[chan->channel2],1041						 chan->extend_name,1042						 postfix);1043		else1044			full_postfix = kasprintf(GFP_KERNEL, "%s_%s",1045						 iio_modifier_names[chan->channel2],1046						 postfix);1047	} else {1048		if (chan->extend_name == NULL || shared_by != IIO_SEPARATE)1049			full_postfix = kstrdup(postfix, GFP_KERNEL);1050		else1051			full_postfix = kasprintf(GFP_KERNEL,1052						 "%s_%s",1053						 chan->extend_name,1054						 postfix);1055	}1056	if (full_postfix == NULL)1057		return -ENOMEM;1058 1059	if (chan->differential) { /* Differential can not have modifier */1060		switch (shared_by) {1061		case IIO_SHARED_BY_ALL:1062			name = kasprintf(GFP_KERNEL, "%s", full_postfix);1063			break;1064		case IIO_SHARED_BY_DIR:1065			name = kasprintf(GFP_KERNEL, "%s_%s",1066						iio_direction[chan->output],1067						full_postfix);1068			break;1069		case IIO_SHARED_BY_TYPE:1070			name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",1071					    iio_direction[chan->output],1072					    iio_chan_type_name_spec[chan->type],1073					    iio_chan_type_name_spec[chan->type],1074					    full_postfix);1075			break;1076		case IIO_SEPARATE:1077			if (!chan->indexed) {1078				WARN(1, "Differential channels must be indexed\n");1079				ret = -EINVAL;1080				goto error_free_full_postfix;1081			}1082			name = kasprintf(GFP_KERNEL,1083					    "%s_%s%d-%s%d_%s",1084					    iio_direction[chan->output],1085					    iio_chan_type_name_spec[chan->type],1086					    chan->channel,1087					    iio_chan_type_name_spec[chan->type],1088					    chan->channel2,1089					    full_postfix);1090			break;1091		}1092	} else { /* Single ended */1093		switch (shared_by) {1094		case IIO_SHARED_BY_ALL:1095			name = kasprintf(GFP_KERNEL, "%s", full_postfix);1096			break;1097		case IIO_SHARED_BY_DIR:1098			name = kasprintf(GFP_KERNEL, "%s_%s",1099						iio_direction[chan->output],1100						full_postfix);1101			break;1102		case IIO_SHARED_BY_TYPE:1103			name = kasprintf(GFP_KERNEL, "%s_%s_%s",1104					    iio_direction[chan->output],1105					    iio_chan_type_name_spec[chan->type],1106					    full_postfix);1107			break;1108 1109		case IIO_SEPARATE:1110			if (chan->indexed)1111				name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",1112						    iio_direction[chan->output],1113						    iio_chan_type_name_spec[chan->type],1114						    chan->channel,1115						    full_postfix);1116			else1117				name = kasprintf(GFP_KERNEL, "%s_%s_%s",1118						    iio_direction[chan->output],1119						    iio_chan_type_name_spec[chan->type],1120						    full_postfix);1121			break;1122		}1123	}1124	if (name == NULL) {1125		ret = -ENOMEM;1126		goto error_free_full_postfix;1127	}1128	dev_attr->attr.name = name;1129 1130	if (readfunc) {1131		dev_attr->attr.mode |= 0444;1132		dev_attr->show = readfunc;1133	}1134 1135	if (writefunc) {1136		dev_attr->attr.mode |= 0200;1137		dev_attr->store = writefunc;1138	}1139 1140error_free_full_postfix:1141	kfree(full_postfix);1142 1143	return ret;1144}1145 1146static void __iio_device_attr_deinit(struct device_attribute *dev_attr)1147{1148	kfree(dev_attr->attr.name);1149}1150 1151int __iio_add_chan_devattr(const char *postfix,1152			   struct iio_chan_spec const *chan,1153			   ssize_t (*readfunc)(struct device *dev,1154					       struct device_attribute *attr,1155					       char *buf),1156			   ssize_t (*writefunc)(struct device *dev,1157						struct device_attribute *attr,1158						const char *buf,1159						size_t len),1160			   u64 mask,1161			   enum iio_shared_by shared_by,1162			   struct device *dev,1163			   struct iio_buffer *buffer,1164			   struct list_head *attr_list)1165{1166	int ret;1167	struct iio_dev_attr *iio_attr, *t;1168 1169	iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL);1170	if (iio_attr == NULL)1171		return -ENOMEM;1172	ret = __iio_device_attr_init(&iio_attr->dev_attr,1173				     postfix, chan,1174				     readfunc, writefunc, shared_by);1175	if (ret)1176		goto error_iio_dev_attr_free;1177	iio_attr->c = chan;1178	iio_attr->address = mask;1179	iio_attr->buffer = buffer;1180	list_for_each_entry(t, attr_list, l)1181		if (strcmp(t->dev_attr.attr.name,1182			   iio_attr->dev_attr.attr.name) == 0) {1183			if (shared_by == IIO_SEPARATE)1184				dev_err(dev, "tried to double register : %s\n",1185					t->dev_attr.attr.name);1186			ret = -EBUSY;1187			goto error_device_attr_deinit;1188		}1189	list_add(&iio_attr->l, attr_list);1190 1191	return 0;1192 1193error_device_attr_deinit:1194	__iio_device_attr_deinit(&iio_attr->dev_attr);1195error_iio_dev_attr_free:1196	kfree(iio_attr);1197	return ret;1198}1199 1200static int iio_device_add_channel_label(struct iio_dev *indio_dev,1201					 struct iio_chan_spec const *chan)1202{1203	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1204	int ret;1205 1206	if (!indio_dev->info->read_label && !chan->extend_name)1207		return 0;1208 1209	ret = __iio_add_chan_devattr("label",1210				     chan,1211				     &iio_read_channel_label,1212				     NULL,1213				     0,1214				     IIO_SEPARATE,1215				     &indio_dev->dev,1216				     NULL,1217				     &iio_dev_opaque->channel_attr_list);1218	if (ret < 0)1219		return ret;1220 1221	return 1;1222}1223 1224static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,1225					 struct iio_chan_spec const *chan,1226					 enum iio_shared_by shared_by,1227					 const long *infomask)1228{1229	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1230	int i, ret, attrcount = 0;1231 1232	for_each_set_bit(i, infomask, sizeof(*infomask)*8) {1233		if (i >= ARRAY_SIZE(iio_chan_info_postfix))1234			return -EINVAL;1235		ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],1236					     chan,1237					     &iio_read_channel_info,1238					     &iio_write_channel_info,1239					     i,1240					     shared_by,1241					     &indio_dev->dev,1242					     NULL,1243					     &iio_dev_opaque->channel_attr_list);1244		if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))1245			continue;1246		if (ret < 0)1247			return ret;1248		attrcount++;1249	}1250 1251	return attrcount;1252}1253 1254static int iio_device_add_info_mask_type_avail(struct iio_dev *indio_dev,1255					       struct iio_chan_spec const *chan,1256					       enum iio_shared_by shared_by,1257					       const long *infomask)1258{1259	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1260	int i, ret, attrcount = 0;1261	char *avail_postfix;1262 1263	for_each_set_bit(i, infomask, sizeof(*infomask) * 8) {1264		if (i >= ARRAY_SIZE(iio_chan_info_postfix))1265			return -EINVAL;1266		avail_postfix = kasprintf(GFP_KERNEL,1267					  "%s_available",1268					  iio_chan_info_postfix[i]);1269		if (!avail_postfix)1270			return -ENOMEM;1271 1272		ret = __iio_add_chan_devattr(avail_postfix,1273					     chan,1274					     &iio_read_channel_info_avail,1275					     NULL,1276					     i,1277					     shared_by,1278					     &indio_dev->dev,1279					     NULL,1280					     &iio_dev_opaque->channel_attr_list);1281		kfree(avail_postfix);1282		if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))1283			continue;1284		if (ret < 0)1285			return ret;1286		attrcount++;1287	}1288 1289	return attrcount;1290}1291 1292static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev,1293					struct iio_chan_spec const *chan)1294{1295	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1296	int ret, attrcount = 0;1297	const struct iio_chan_spec_ext_info *ext_info;1298 1299	if (chan->channel < 0)1300		return 0;1301	ret = iio_device_add_info_mask_type(indio_dev, chan,1302					    IIO_SEPARATE,1303					    &chan->info_mask_separate);1304	if (ret < 0)1305		return ret;1306	attrcount += ret;1307 1308	ret = iio_device_add_info_mask_type_avail(indio_dev, chan,1309						  IIO_SEPARATE,1310						  &chan->info_mask_separate_available);1311	if (ret < 0)1312		return ret;1313	attrcount += ret;1314 1315	ret = iio_device_add_info_mask_type(indio_dev, chan,1316					    IIO_SHARED_BY_TYPE,1317					    &chan->info_mask_shared_by_type);1318	if (ret < 0)1319		return ret;1320	attrcount += ret;1321 1322	ret = iio_device_add_info_mask_type_avail(indio_dev, chan,1323						  IIO_SHARED_BY_TYPE,1324						  &chan->info_mask_shared_by_type_available);1325	if (ret < 0)1326		return ret;1327	attrcount += ret;1328 1329	ret = iio_device_add_info_mask_type(indio_dev, chan,1330					    IIO_SHARED_BY_DIR,1331					    &chan->info_mask_shared_by_dir);1332	if (ret < 0)1333		return ret;1334	attrcount += ret;1335 1336	ret = iio_device_add_info_mask_type_avail(indio_dev, chan,1337						  IIO_SHARED_BY_DIR,1338						  &chan->info_mask_shared_by_dir_available);1339	if (ret < 0)1340		return ret;1341	attrcount += ret;1342 1343	ret = iio_device_add_info_mask_type(indio_dev, chan,1344					    IIO_SHARED_BY_ALL,1345					    &chan->info_mask_shared_by_all);1346	if (ret < 0)1347		return ret;1348	attrcount += ret;1349 1350	ret = iio_device_add_info_mask_type_avail(indio_dev, chan,1351						  IIO_SHARED_BY_ALL,1352						  &chan->info_mask_shared_by_all_available);1353	if (ret < 0)1354		return ret;1355	attrcount += ret;1356 1357	ret = iio_device_add_channel_label(indio_dev, chan);1358	if (ret < 0)1359		return ret;1360	attrcount += ret;1361 1362	if (chan->ext_info) {1363		unsigned int i = 0;1364 1365		for (ext_info = chan->ext_info; ext_info->name; ext_info++) {1366			ret = __iio_add_chan_devattr(ext_info->name,1367					chan,1368					ext_info->read ?1369					    &iio_read_channel_ext_info : NULL,1370					ext_info->write ?1371					    &iio_write_channel_ext_info : NULL,1372					i,1373					ext_info->shared,1374					&indio_dev->dev,1375					NULL,1376					&iio_dev_opaque->channel_attr_list);1377			i++;1378			if (ret == -EBUSY && ext_info->shared)1379				continue;1380 1381			if (ret)1382				return ret;1383 1384			attrcount++;1385		}1386	}1387 1388	return attrcount;1389}1390 1391/**1392 * iio_free_chan_devattr_list() - Free a list of IIO device attributes1393 * @attr_list: List of IIO device attributes1394 *1395 * This function frees the memory allocated for each of the IIO device1396 * attributes in the list.1397 */1398void iio_free_chan_devattr_list(struct list_head *attr_list)1399{1400	struct iio_dev_attr *p, *n;1401 1402	list_for_each_entry_safe(p, n, attr_list, l) {1403		kfree_const(p->dev_attr.attr.name);1404		list_del(&p->l);1405		kfree(p);1406	}1407}1408 1409static ssize_t name_show(struct device *dev, struct device_attribute *attr,1410			 char *buf)1411{1412	struct iio_dev *indio_dev = dev_to_iio_dev(dev);1413 1414	return sysfs_emit(buf, "%s\n", indio_dev->name);1415}1416 1417static DEVICE_ATTR_RO(name);1418 1419static ssize_t label_show(struct device *dev, struct device_attribute *attr,1420			  char *buf)1421{1422	struct iio_dev *indio_dev = dev_to_iio_dev(dev);1423 1424	return sysfs_emit(buf, "%s\n", indio_dev->label);1425}1426 1427static DEVICE_ATTR_RO(label);1428 1429static const char * const clock_names[] = {1430	[CLOCK_REALTIME]	 	= "realtime",1431	[CLOCK_MONOTONIC]	 	= "monotonic",1432	[CLOCK_PROCESS_CPUTIME_ID]	= "process_cputime_id",1433	[CLOCK_THREAD_CPUTIME_ID]	= "thread_cputime_id",1434	[CLOCK_MONOTONIC_RAW]	 	= "monotonic_raw",1435	[CLOCK_REALTIME_COARSE]	 	= "realtime_coarse",1436	[CLOCK_MONOTONIC_COARSE] 	= "monotonic_coarse",1437	[CLOCK_BOOTTIME]	 	= "boottime",1438	[CLOCK_REALTIME_ALARM]		= "realtime_alarm",1439	[CLOCK_BOOTTIME_ALARM]		= "boottime_alarm",1440	[CLOCK_SGI_CYCLE]		= "sgi_cycle",1441	[CLOCK_TAI]		 	= "tai",1442};1443 1444static ssize_t current_timestamp_clock_show(struct device *dev,1445					    struct device_attribute *attr,1446					    char *buf)1447{1448	const struct iio_dev *indio_dev = dev_to_iio_dev(dev);1449	const clockid_t clk = iio_device_get_clock(indio_dev);1450 1451	switch (clk) {1452	case CLOCK_REALTIME:1453	case CLOCK_MONOTONIC:1454	case CLOCK_MONOTONIC_RAW:1455	case CLOCK_REALTIME_COARSE:1456	case CLOCK_MONOTONIC_COARSE:1457	case CLOCK_BOOTTIME:1458	case CLOCK_TAI:1459		break;1460	default:1461		BUG();1462	}1463 1464	return sysfs_emit(buf, "%s\n", clock_names[clk]);1465}1466 1467static ssize_t current_timestamp_clock_store(struct device *dev,1468					     struct device_attribute *attr,1469					     const char *buf, size_t len)1470{1471	clockid_t clk;1472	int ret;1473 1474	ret = sysfs_match_string(clock_names, buf);1475	if (ret < 0)1476		return ret;1477	clk = ret;1478 1479	switch (clk) {1480	case CLOCK_REALTIME:1481	case CLOCK_MONOTONIC:1482	case CLOCK_MONOTONIC_RAW:1483	case CLOCK_REALTIME_COARSE:1484	case CLOCK_MONOTONIC_COARSE:1485	case CLOCK_BOOTTIME:1486	case CLOCK_TAI:1487		break;1488	default:1489		return -EINVAL;1490	}1491 1492	ret = iio_device_set_clock(dev_to_iio_dev(dev), clk);1493	if (ret)1494		return ret;1495 1496	return len;1497}1498 1499int iio_device_register_sysfs_group(struct iio_dev *indio_dev,1500				    const struct attribute_group *group)1501{1502	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1503	const struct attribute_group **new, **old = iio_dev_opaque->groups;1504	unsigned int cnt = iio_dev_opaque->groupcounter;1505 1506	new = krealloc_array(old, cnt + 2, sizeof(*new), GFP_KERNEL);1507	if (!new)1508		return -ENOMEM;1509 1510	new[iio_dev_opaque->groupcounter++] = group;1511	new[iio_dev_opaque->groupcounter] = NULL;1512 1513	iio_dev_opaque->groups = new;1514 1515	return 0;1516}1517 1518static DEVICE_ATTR_RW(current_timestamp_clock);1519 1520static int iio_device_register_sysfs(struct iio_dev *indio_dev)1521{1522	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1523	int i, ret = 0, attrcount, attrn, attrcount_orig = 0;1524	struct iio_dev_attr *p;1525	struct attribute **attr, *clk = NULL;1526 1527	/* First count elements in any existing group */1528	if (indio_dev->info->attrs) {1529		attr = indio_dev->info->attrs->attrs;1530		while (*attr++ != NULL)1531			attrcount_orig++;1532	}1533	attrcount = attrcount_orig;1534	/*1535	 * New channel registration method - relies on the fact a group does1536	 * not need to be initialized if its name is NULL.1537	 */1538	if (indio_dev->channels)1539		for (i = 0; i < indio_dev->num_channels; i++) {1540			const struct iio_chan_spec *chan =1541				&indio_dev->channels[i];1542 1543			if (chan->type == IIO_TIMESTAMP)1544				clk = &dev_attr_current_timestamp_clock.attr;1545 1546			ret = iio_device_add_channel_sysfs(indio_dev, chan);1547			if (ret < 0)1548				goto error_clear_attrs;1549			attrcount += ret;1550		}1551 1552	if (iio_dev_opaque->event_interface)1553		clk = &dev_attr_current_timestamp_clock.attr;1554 1555	if (indio_dev->name)1556		attrcount++;1557	if (indio_dev->label)1558		attrcount++;1559	if (clk)1560		attrcount++;1561 1562	iio_dev_opaque->chan_attr_group.attrs =1563		kcalloc(attrcount + 1,1564			sizeof(iio_dev_opaque->chan_attr_group.attrs[0]),1565			GFP_KERNEL);1566	if (iio_dev_opaque->chan_attr_group.attrs == NULL) {1567		ret = -ENOMEM;1568		goto error_clear_attrs;1569	}1570	/* Copy across original attributes, and point to original binary attributes */1571	if (indio_dev->info->attrs) {1572		memcpy(iio_dev_opaque->chan_attr_group.attrs,1573		       indio_dev->info->attrs->attrs,1574		       sizeof(iio_dev_opaque->chan_attr_group.attrs[0])1575		       *attrcount_orig);1576		iio_dev_opaque->chan_attr_group.is_visible =1577			indio_dev->info->attrs->is_visible;1578		iio_dev_opaque->chan_attr_group.bin_attrs =1579			indio_dev->info->attrs->bin_attrs;1580	}1581	attrn = attrcount_orig;1582	/* Add all elements from the list. */1583	list_for_each_entry(p, &iio_dev_opaque->channel_attr_list, l)1584		iio_dev_opaque->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr;1585	if (indio_dev->name)1586		iio_dev_opaque->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr;1587	if (indio_dev->label)1588		iio_dev_opaque->chan_attr_group.attrs[attrn++] = &dev_attr_label.attr;1589	if (clk)1590		iio_dev_opaque->chan_attr_group.attrs[attrn++] = clk;1591 1592	ret = iio_device_register_sysfs_group(indio_dev,1593					      &iio_dev_opaque->chan_attr_group);1594	if (ret)1595		goto error_free_chan_attrs;1596 1597	return 0;1598 1599error_free_chan_attrs:1600	kfree(iio_dev_opaque->chan_attr_group.attrs);1601	iio_dev_opaque->chan_attr_group.attrs = NULL;1602error_clear_attrs:1603	iio_free_chan_devattr_list(&iio_dev_opaque->channel_attr_list);1604 1605	return ret;1606}1607 1608static void iio_device_unregister_sysfs(struct iio_dev *indio_dev)1609{1610	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1611 1612	iio_free_chan_devattr_list(&iio_dev_opaque->channel_attr_list);1613	kfree(iio_dev_opaque->chan_attr_group.attrs);1614	iio_dev_opaque->chan_attr_group.attrs = NULL;1615	kfree(iio_dev_opaque->groups);1616	iio_dev_opaque->groups = NULL;1617}1618 1619static void iio_dev_release(struct device *device)1620{1621	struct iio_dev *indio_dev = dev_to_iio_dev(device);1622	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1623 1624	if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)1625		iio_device_unregister_trigger_consumer(indio_dev);1626	iio_device_unregister_eventset(indio_dev);1627	iio_device_unregister_sysfs(indio_dev);1628 1629	iio_device_detach_buffers(indio_dev);1630 1631	lockdep_unregister_key(&iio_dev_opaque->mlock_key);1632 1633	ida_free(&iio_ida, iio_dev_opaque->id);1634	kfree(iio_dev_opaque);1635}1636 1637const struct device_type iio_device_type = {1638	.name = "iio_device",1639	.release = iio_dev_release,1640};1641 1642/**1643 * iio_device_alloc() - allocate an iio_dev from a driver1644 * @parent:		Parent device.1645 * @sizeof_priv:	Space to allocate for private structure.1646 *1647 * Returns:1648 * Pointer to allocated iio_dev on success, NULL on failure.1649 */1650struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv)1651{1652	struct iio_dev_opaque *iio_dev_opaque;1653	struct iio_dev *indio_dev;1654	size_t alloc_size;1655 1656	if (sizeof_priv)1657		alloc_size = ALIGN(sizeof(*iio_dev_opaque), IIO_DMA_MINALIGN) + sizeof_priv;1658	else1659		alloc_size = sizeof(*iio_dev_opaque);1660 1661	iio_dev_opaque = kzalloc(alloc_size, GFP_KERNEL);1662	if (!iio_dev_opaque)1663		return NULL;1664 1665	indio_dev = &iio_dev_opaque->indio_dev;1666 1667	if (sizeof_priv)1668		indio_dev->priv = (char *)iio_dev_opaque +1669			ALIGN(sizeof(*iio_dev_opaque), IIO_DMA_MINALIGN);1670 1671	indio_dev->dev.parent = parent;1672	indio_dev->dev.type = &iio_device_type;1673	indio_dev->dev.bus = &iio_bus_type;1674	device_initialize(&indio_dev->dev);1675	mutex_init(&iio_dev_opaque->mlock);1676	mutex_init(&iio_dev_opaque->info_exist_lock);1677	INIT_LIST_HEAD(&iio_dev_opaque->channel_attr_list);1678 1679	iio_dev_opaque->id = ida_alloc(&iio_ida, GFP_KERNEL);1680	if (iio_dev_opaque->id < 0) {1681		/* cannot use a dev_err as the name isn't available */1682		pr_err("failed to get device id\n");1683		kfree(iio_dev_opaque);1684		return NULL;1685	}1686 1687	if (dev_set_name(&indio_dev->dev, "iio:device%d", iio_dev_opaque->id)) {1688		ida_free(&iio_ida, iio_dev_opaque->id);1689		kfree(iio_dev_opaque);1690		return NULL;1691	}1692 1693	INIT_LIST_HEAD(&iio_dev_opaque->buffer_list);1694	INIT_LIST_HEAD(&iio_dev_opaque->ioctl_handlers);1695 1696	lockdep_register_key(&iio_dev_opaque->mlock_key);1697	lockdep_set_class(&iio_dev_opaque->mlock, &iio_dev_opaque->mlock_key);1698 1699	return indio_dev;1700}1701EXPORT_SYMBOL(iio_device_alloc);1702 1703/**1704 * iio_device_free() - free an iio_dev from a driver1705 * @dev:		the iio_dev associated with the device1706 */1707void iio_device_free(struct iio_dev *dev)1708{1709	if (dev)1710		put_device(&dev->dev);1711}1712EXPORT_SYMBOL(iio_device_free);1713 1714static void devm_iio_device_release(void *iio_dev)1715{1716	iio_device_free(iio_dev);1717}1718 1719/**1720 * devm_iio_device_alloc - Resource-managed iio_device_alloc()1721 * @parent:		Device to allocate iio_dev for, and parent for this IIO device1722 * @sizeof_priv:	Space to allocate for private structure.1723 *1724 * Managed iio_device_alloc. iio_dev allocated with this function is1725 * automatically freed on driver detach.1726 *1727 * Returns:1728 * Pointer to allocated iio_dev on success, NULL on failure.1729 */1730struct iio_dev *devm_iio_device_alloc(struct device *parent, int sizeof_priv)1731{1732	struct iio_dev *iio_dev;1733	int ret;1734 1735	iio_dev = iio_device_alloc(parent, sizeof_priv);1736	if (!iio_dev)1737		return NULL;1738 1739	ret = devm_add_action_or_reset(parent, devm_iio_device_release,1740				       iio_dev);1741	if (ret)1742		return NULL;1743 1744	return iio_dev;1745}1746EXPORT_SYMBOL_GPL(devm_iio_device_alloc);1747 1748/**1749 * iio_chrdev_open() - chrdev file open for buffer access and ioctls1750 * @inode:	Inode structure for identifying the device in the file system1751 * @filp:	File structure for iio device used to keep and later access1752 *		private data1753 *1754 * Returns: 0 on success or -EBUSY if the device is already opened1755 */1756static int iio_chrdev_open(struct inode *inode, struct file *filp)1757{1758	struct iio_dev_opaque *iio_dev_opaque =1759		container_of(inode->i_cdev, struct iio_dev_opaque, chrdev);1760	struct iio_dev *indio_dev = &iio_dev_opaque->indio_dev;1761	struct iio_dev_buffer_pair *ib;1762 1763	if (test_and_set_bit(IIO_BUSY_BIT_POS, &iio_dev_opaque->flags))1764		return -EBUSY;1765 1766	iio_device_get(indio_dev);1767 1768	ib = kmalloc(sizeof(*ib), GFP_KERNEL);1769	if (!ib) {1770		iio_device_put(indio_dev);1771		clear_bit(IIO_BUSY_BIT_POS, &iio_dev_opaque->flags);1772		return -ENOMEM;1773	}1774 1775	ib->indio_dev = indio_dev;1776	ib->buffer = indio_dev->buffer;1777 1778	filp->private_data = ib;1779 1780	return 0;1781}1782 1783/**1784 * iio_chrdev_release() - chrdev file close buffer access and ioctls1785 * @inode:	Inode structure pointer for the char device1786 * @filp:	File structure pointer for the char device1787 *1788 * Returns: 0 for successful release.1789 */1790static int iio_chrdev_release(struct inode *inode, struct file *filp)1791{1792	struct iio_dev_buffer_pair *ib = filp->private_data;1793	struct iio_dev_opaque *iio_dev_opaque =1794		container_of(inode->i_cdev, struct iio_dev_opaque, chrdev);1795	struct iio_dev *indio_dev = &iio_dev_opaque->indio_dev;1796 1797	kfree(ib);1798	clear_bit(IIO_BUSY_BIT_POS, &iio_dev_opaque->flags);1799	iio_device_put(indio_dev);1800 1801	return 0;1802}1803 1804void iio_device_ioctl_handler_register(struct iio_dev *indio_dev,1805				       struct iio_ioctl_handler *h)1806{1807	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1808 1809	list_add_tail(&h->entry, &iio_dev_opaque->ioctl_handlers);1810}1811 1812void iio_device_ioctl_handler_unregister(struct iio_ioctl_handler *h)1813{1814	list_del(&h->entry);1815}1816 1817static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)1818{1819	struct iio_dev_buffer_pair *ib = filp->private_data;1820	struct iio_dev *indio_dev = ib->indio_dev;1821	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);1822	struct iio_ioctl_handler *h;1823	int ret;1824 1825	guard(mutex)(&iio_dev_opaque->info_exist_lock);1826	/*1827	 * The NULL check here is required to prevent crashing when a device1828	 * is being removed while userspace would still have open file handles1829	 * to try to access this device.1830	 */1831	if (!indio_dev->info)1832		return -ENODEV;1833 1834	list_for_each_entry(h, &iio_dev_opaque->ioctl_handlers, entry) {1835		ret = h->ioctl(indio_dev, filp, cmd, arg);1836		if (ret != IIO_IOCTL_UNHANDLED)1837			return ret;1838	}1839 1840	return -ENODEV;1841}1842 1843static const struct file_operations iio_buffer_fileops = {1844	.owner = THIS_MODULE,1845	.llseek = noop_llseek,1846	.read = iio_buffer_read_outer_addr,1847	.write = iio_buffer_write_outer_addr,1848	.poll = iio_buffer_poll_addr,1849	.unlocked_ioctl = iio_ioctl,1850	.compat_ioctl = compat_ptr_ioctl,1851	.open = iio_chrdev_open,1852	.release = iio_chrdev_release,1853};1854 1855static const struct file_operations iio_event_fileops = {1856	.owner = THIS_MODULE,1857	.llseek = noop_llseek,1858	.unlocked_ioctl = iio_ioctl,1859	.compat_ioctl = compat_ptr_ioctl,1860	.open = iio_chrdev_open,1861	.release = iio_chrdev_release,1862};1863 1864static int iio_check_unique_scan_index(struct iio_dev *indio_dev)1865{1866	int i, j;1867	const struct iio_chan_spec *channels = indio_dev->channels;1868 1869	if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES))1870		return 0;1871 1872	for (i = 0; i < indio_dev->num_channels - 1; i++) {1873		if (channels[i].scan_index < 0)1874			continue;1875		for (j = i + 1; j < indio_dev->num_channels; j++)1876			if (channels[i].scan_index == channels[j].scan_index) {1877				dev_err(&indio_dev->dev,1878					"Duplicate scan index %d\n",1879					channels[i].scan_index);1880				return -EINVAL;1881			}1882	}1883 1884	return 0;1885}1886 1887static int iio_check_extended_name(const struct iio_dev *indio_dev)1888{1889	unsigned int i;1890 1891	if (!indio_dev->info->read_label)1892		return 0;1893 1894	for (i = 0; i < indio_dev->num_channels; i++) {1895		if (indio_dev->channels[i].extend_name) {1896			dev_err(&indio_dev->dev,1897				"Cannot use labels and extend_name at the same time\n");1898			return -EINVAL;1899		}1900	}1901 1902	return 0;1903}1904 1905static const struct iio_buffer_setup_ops noop_ring_setup_ops;1906 1907static void iio_sanity_check_avail_scan_masks(struct iio_dev *indio_dev)1908{1909	unsigned int num_masks, masklength, longs_per_mask;1910	const unsigned long *av_masks;1911	int i;1912 1913	av_masks = indio_dev->available_scan_masks;1914	masklength = iio_get_masklength(indio_dev);1915	longs_per_mask = BITS_TO_LONGS(masklength);1916 1917	/*1918	 * The code determining how many available_scan_masks is in the array1919	 * will be assuming the end of masks when first long with all bits1920	 * zeroed is encountered. This is incorrect for masks where mask1921	 * consists of more than one long, and where some of the available masks1922	 * has long worth of bits zeroed (but has subsequent bit(s) set). This1923	 * is a safety measure against bug where array of masks is terminated by1924	 * a single zero while mask width is greater than width of a long.1925	 */1926	if (longs_per_mask > 1)1927		dev_warn(indio_dev->dev.parent,1928			 "multi long available scan masks not fully supported\n");1929 1930	if (bitmap_empty(av_masks, masklength))1931		dev_warn(indio_dev->dev.parent, "empty scan mask\n");1932 1933	for (num_masks = 0; *av_masks; num_masks++)1934		av_masks += longs_per_mask;1935 1936	if (num_masks < 2)1937		return;1938 1939	av_masks = indio_dev->available_scan_masks;1940 1941	/*1942	 * Go through all the masks from first to one before the last, and see1943	 * that no mask found later from the available_scan_masks array is a1944	 * subset of mask found earlier. If this happens, then the mask found1945	 * later will never get used because scanning the array is stopped when1946	 * the first suitable mask is found. Drivers should order the array of1947	 * available masks in the order of preference (presumably the least1948	 * costy to access masks first).1949	 */1950	for (i = 0; i < num_masks - 1; i++) {1951		const unsigned long *mask1;1952		int j;1953 1954		mask1 = av_masks + i * longs_per_mask;1955		for (j = i + 1; j < num_masks; j++) {1956			const unsigned long *mask2;1957 1958			mask2 = av_masks + j * longs_per_mask;1959			if (bitmap_subset(mask2, mask1, masklength))1960				dev_warn(indio_dev->dev.parent,1961					 "available_scan_mask %d subset of %d. Never used\n",1962					 j, i);1963		}1964	}1965}1966 1967/**1968 * iio_active_scan_mask_index - Get index of the active scan mask inside the1969 * available scan masks array1970 * @indio_dev: the IIO device containing the active and available scan masks1971 *1972 * Returns: the index or -EINVAL if  active_scan_mask is not set1973 */1974int iio_active_scan_mask_index(struct iio_dev *indio_dev)1975 1976{1977	const unsigned long *av_masks;1978	unsigned int masklength = iio_get_masklength(indio_dev);1979	int i = 0;1980 1981	if (!indio_dev->active_scan_mask)1982		return -EINVAL;1983 1984	/*1985	 * As in iio_scan_mask_match and iio_sanity_check_avail_scan_masks,1986	 * the condition here do not handle multi-long masks correctly.1987	 * It only checks the first long to be zero, and will use such mask1988	 * as a terminator even if there was bits set after the first long.1989	 *1990	 * This should be fine since the available_scan_mask has already been1991	 * sanity tested using iio_sanity_check_avail_scan_masks.1992	 *1993	 * See iio_scan_mask_match and iio_sanity_check_avail_scan_masks for1994	 * more details1995	 */1996	av_masks = indio_dev->available_scan_masks;1997	while (*av_masks) {1998		if (indio_dev->active_scan_mask == av_masks)1999			return i;2000		av_masks += BITS_TO_LONGS(masklength);2001		i++;2002	}2003 2004	dev_warn(indio_dev->dev.parent,2005		 "active scan mask is not part of the available scan masks\n");2006	return -EINVAL;2007}2008EXPORT_SYMBOL_GPL(iio_active_scan_mask_index);2009 2010int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)2011{2012	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);2013	struct fwnode_handle *fwnode = NULL;2014	int ret;2015 2016	if (!indio_dev->info)2017		return -EINVAL;2018 2019	iio_dev_opaque->driver_module = this_mod;2020 2021	/* If the calling driver did not initialize firmware node, do it here */2022	if (dev_fwnode(&indio_dev->dev))2023		fwnode = dev_fwnode(&indio_dev->dev);2024	/* The default dummy IIO device has no parent */2025	else if (indio_dev->dev.parent)2026		fwnode = dev_fwnode(indio_dev->dev.parent);2027	device_set_node(&indio_dev->dev, fwnode);2028 2029	fwnode_property_read_string(fwnode, "label", &indio_dev->label);2030 2031	ret = iio_check_unique_scan_index(indio_dev);2032	if (ret < 0)2033		return ret;2034 2035	ret = iio_check_extended_name(indio_dev);2036	if (ret < 0)2037		return ret;2038 2039	iio_device_register_debugfs(indio_dev);2040 2041	ret = iio_buffers_alloc_sysfs_and_mask(indio_dev);2042	if (ret) {2043		dev_err(indio_dev->dev.parent,2044			"Failed to create buffer sysfs interfaces\n");2045		goto error_unreg_debugfs;2046	}2047 2048	if (indio_dev->available_scan_masks)2049		iio_sanity_check_avail_scan_masks(indio_dev);2050 2051	ret = iio_device_register_sysfs(indio_dev);2052	if (ret) {2053		dev_err(indio_dev->dev.parent,2054			"Failed to register sysfs interfaces\n");2055		goto error_buffer_free_sysfs;2056	}2057	ret = iio_device_register_eventset(indio_dev);2058	if (ret) {2059		dev_err(indio_dev->dev.parent,2060			"Failed to register event set\n");2061		goto error_free_sysfs;2062	}2063	if (indio_dev->modes & INDIO_ALL_TRIGGERED_MODES)2064		iio_device_register_trigger_consumer(indio_dev);2065 2066	if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) &&2067		indio_dev->setup_ops == NULL)2068		indio_dev->setup_ops = &noop_ring_setup_ops;2069 2070	if (iio_dev_opaque->attached_buffers_cnt)2071		cdev_init(&iio_dev_opaque->chrdev, &iio_buffer_fileops);2072	else if (iio_dev_opaque->event_interface)2073		cdev_init(&iio_dev_opaque->chrdev, &iio_event_fileops);2074 2075	if (iio_dev_opaque->attached_buffers_cnt || iio_dev_opaque->event_interface) {2076		indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), iio_dev_opaque->id);2077		iio_dev_opaque->chrdev.owner = this_mod;2078	}2079 2080	/* assign device groups now; they should be all registered now */2081	indio_dev->dev.groups = iio_dev_opaque->groups;2082 2083	ret = cdev_device_add(&iio_dev_opaque->chrdev, &indio_dev->dev);2084	if (ret < 0)2085		goto error_unreg_eventset;2086 2087	return 0;2088 2089error_unreg_eventset:2090	iio_device_unregister_eventset(indio_dev);2091error_free_sysfs:2092	iio_device_unregister_sysfs(indio_dev);2093error_buffer_free_sysfs:2094	iio_buffers_free_sysfs_and_mask(indio_dev);2095error_unreg_debugfs:2096	iio_device_unregister_debugfs(indio_dev);2097	return ret;2098}2099EXPORT_SYMBOL(__iio_device_register);2100 2101/**2102 * iio_device_unregister() - unregister a device from the IIO subsystem2103 * @indio_dev:		Device structure representing the device.2104 */2105void iio_device_unregister(struct iio_dev *indio_dev)2106{2107	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);2108 2109	cdev_device_del(&iio_dev_opaque->chrdev, &indio_dev->dev);2110 2111	scoped_guard(mutex, &iio_dev_opaque->info_exist_lock) {2112		iio_device_unregister_debugfs(indio_dev);2113 2114		iio_disable_all_buffers(indio_dev);2115 2116		indio_dev->info = NULL;2117 2118		iio_device_wakeup_eventset(indio_dev);2119		iio_buffer_wakeup_poll(indio_dev);2120	}2121 2122	iio_buffers_free_sysfs_and_mask(indio_dev);2123}2124EXPORT_SYMBOL(iio_device_unregister);2125 2126static void devm_iio_device_unreg(void *indio_dev)2127{2128	iio_device_unregister(indio_dev);2129}2130 2131int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,2132			       struct module *this_mod)2133{2134	int ret;2135 2136	ret = __iio_device_register(indio_dev, this_mod);2137	if (ret)2138		return ret;2139 2140	return devm_add_action_or_reset(dev, devm_iio_device_unreg, indio_dev);2141}2142EXPORT_SYMBOL_GPL(__devm_iio_device_register);2143 2144/**2145 * iio_device_claim_direct_mode - Keep device in direct mode2146 * @indio_dev:	the iio_dev associated with the device2147 *2148 * If the device is in direct mode it is guaranteed to stay2149 * that way until iio_device_release_direct_mode() is called.2150 *2151 * Use with iio_device_release_direct_mode()2152 *2153 * Returns: 0 on success, -EBUSY on failure.2154 */2155int iio_device_claim_direct_mode(struct iio_dev *indio_dev)2156{2157	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);2158 2159	mutex_lock(&iio_dev_opaque->mlock);2160 2161	if (iio_buffer_enabled(indio_dev)) {2162		mutex_unlock(&iio_dev_opaque->mlock);2163		return -EBUSY;2164	}2165	return 0;2166}2167EXPORT_SYMBOL_GPL(iio_device_claim_direct_mode);2168 2169/**2170 * iio_device_release_direct_mode - releases claim on direct mode2171 * @indio_dev:	the iio_dev associated with the device2172 *2173 * Release the claim. Device is no longer guaranteed to stay2174 * in direct mode.2175 *2176 * Use with iio_device_claim_direct_mode()2177 */2178void iio_device_release_direct_mode(struct iio_dev *indio_dev)2179{2180	mutex_unlock(&to_iio_dev_opaque(indio_dev)->mlock);2181}2182EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);2183 2184/**2185 * iio_device_claim_buffer_mode - Keep device in buffer mode2186 * @indio_dev:	the iio_dev associated with the device2187 *2188 * If the device is in buffer mode it is guaranteed to stay2189 * that way until iio_device_release_buffer_mode() is called.2190 *2191 * Use with iio_device_release_buffer_mode().2192 *2193 * Returns: 0 on success, -EBUSY on failure.2194 */2195int iio_device_claim_buffer_mode(struct iio_dev *indio_dev)2196{2197	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);2198 2199	mutex_lock(&iio_dev_opaque->mlock);2200 2201	if (iio_buffer_enabled(indio_dev))2202		return 0;2203 2204	mutex_unlock(&iio_dev_opaque->mlock);2205	return -EBUSY;2206}2207EXPORT_SYMBOL_GPL(iio_device_claim_buffer_mode);2208 2209/**2210 * iio_device_release_buffer_mode - releases claim on buffer mode2211 * @indio_dev:	the iio_dev associated with the device2212 *2213 * Release the claim. Device is no longer guaranteed to stay2214 * in buffer mode.2215 *2216 * Use with iio_device_claim_buffer_mode().2217 */2218void iio_device_release_buffer_mode(struct iio_dev *indio_dev)2219{2220	mutex_unlock(&to_iio_dev_opaque(indio_dev)->mlock);2221}2222EXPORT_SYMBOL_GPL(iio_device_release_buffer_mode);2223 2224/**2225 * iio_device_get_current_mode() - helper function providing read-only access to2226 *				   the opaque @currentmode variable2227 * @indio_dev:			   IIO device structure for device2228 */2229int iio_device_get_current_mode(struct iio_dev *indio_dev)2230{2231	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);2232 2233	return iio_dev_opaque->currentmode;2234}2235EXPORT_SYMBOL_GPL(iio_device_get_current_mode);2236 2237subsys_initcall(iio_init);2238module_exit(iio_exit);2239 2240MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");2241MODULE_DESCRIPTION("Industrial I/O core");2242MODULE_LICENSE("GPL");2243