/* The industrial I/O core * * Copyright (c) 2008 Jonathan Cameron * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published by * the Free Software Foundation. * * Based on elements of hwmon and input subsystems. */ #define pr_fmt(fmt) "iio-core: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "iio_core.h" #include "iio_core_trigger.h" #include #include #include /* IDA to assign each registered device a unique id */ static DEFINE_IDA(iio_ida); static dev_t iio_devt; #define IIO_DEV_MAX 256 struct bus_type iio_bus_type = { .name = "iio", }; EXPORT_SYMBOL(iio_bus_type); static struct dentry *iio_debugfs_dentry; static const char * const iio_direction[] = { [0] = "in", [1] = "out", }; static const char * const iio_chan_type_name_spec[] = { [IIO_VOLTAGE] = "voltage", [IIO_CURRENT] = "current", [IIO_POWER] = "power", [IIO_ACCEL] = "accel", [IIO_ANGL_VEL] = "anglvel", [IIO_MAGN] = "magn", [IIO_LIGHT] = "illuminance", [IIO_INTENSITY] = "intensity", [IIO_PROXIMITY] = "proximity", [IIO_TEMP] = "temp", [IIO_INCLI] = "incli", [IIO_ROT] = "rot", [IIO_ANGL] = "angl", [IIO_TIMESTAMP] = "timestamp", [IIO_CAPACITANCE] = "capacitance", [IIO_ALTVOLTAGE] = "altvoltage", [IIO_CCT] = "cct", [IIO_PRESSURE] = "pressure", [IIO_HUMIDITYRELATIVE] = "humidityrelative", [IIO_ACTIVITY] = "activity", [IIO_STEPS] = "steps", [IIO_ENERGY] = "energy", [IIO_DISTANCE] = "distance", [IIO_VELOCITY] = "velocity", }; static const char * const iio_modifier_names[] = { [IIO_MOD_X] = "x", [IIO_MOD_Y] = "y", [IIO_MOD_Z] = "z", [IIO_MOD_X_AND_Y] = "x&y", [IIO_MOD_X_AND_Z] = "x&z", [IIO_MOD_Y_AND_Z] = "y&z", [IIO_MOD_X_AND_Y_AND_Z] = "x&y&z", [IIO_MOD_X_OR_Y] = "x|y", [IIO_MOD_X_OR_Z] = "x|z", [IIO_MOD_Y_OR_Z] = "y|z", [IIO_MOD_X_OR_Y_OR_Z] = "x|y|z", [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)", [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2", [IIO_MOD_LIGHT_BOTH] = "both", [IIO_MOD_LIGHT_IR] = "ir", [IIO_MOD_LIGHT_CLEAR] = "clear", [IIO_MOD_LIGHT_RED] = "red", [IIO_MOD_LIGHT_GREEN] = "green", [IIO_MOD_LIGHT_BLUE] = "blue", [IIO_MOD_QUATERNION] = "quaternion", [IIO_MOD_TEMP_AMBIENT] = "ambient", [IIO_MOD_TEMP_OBJECT] = "object", [IIO_MOD_NORTH_MAGN] = "from_north_magnetic", [IIO_MOD_NORTH_TRUE] = "from_north_true", [IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp", [IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp", [IIO_MOD_RUNNING] = "running", [IIO_MOD_JOGGING] = "jogging", [IIO_MOD_WALKING] = "walking", [IIO_MOD_STILL] = "still", [IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)", [IIO_MOD_I] = "i", [IIO_MOD_Q] = "q", }; /* relies on pairs of these shared then separate */ static const char * const iio_chan_info_postfix[] = { [IIO_CHAN_INFO_RAW] = "raw", [IIO_CHAN_INFO_PROCESSED] = "input", [IIO_CHAN_INFO_SCALE] = "scale", [IIO_CHAN_INFO_OFFSET] = "offset", [IIO_CHAN_INFO_CALIBSCALE] = "calibscale", [IIO_CHAN_INFO_CALIBBIAS] = "calibbias", [IIO_CHAN_INFO_PEAK] = "peak_raw", [IIO_CHAN_INFO_PEAK_SCALE] = "peak_scale", [IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW] = "quadrature_correction_raw", [IIO_CHAN_INFO_AVERAGE_RAW] = "mean_raw", [IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY] = "filter_low_pass_3db_frequency", [IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY] = "filter_high_pass_3db_frequency", [IIO_CHAN_INFO_SAMP_FREQ] = "sampling_frequency", [IIO_CHAN_INFO_FREQUENCY] = "frequency", [IIO_CHAN_INFO_PHASE] = "phase", [IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain", [IIO_CHAN_INFO_HYSTERESIS] = "hysteresis", [IIO_CHAN_INFO_INT_TIME] = "integration_time", [IIO_CHAN_INFO_ENABLE] = "en", [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight", [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight", [IIO_CHAN_INFO_DEBOUNCE_COUNT] = "debounce_count", [IIO_CHAN_INFO_DEBOUNCE_TIME] = "debounce_time", [IIO_CHAN_INFO_CALIBEMISSIVITY] = "calibemissivity", [IIO_CHAN_INFO_OVERSAMPLING_RATIO] = "oversampling_ratio", }; /** * iio_find_channel_from_si() - get channel from its scan index * @indio_dev: device * @si: scan index to match */ const struct iio_chan_spec *iio_find_channel_from_si(struct iio_dev *indio_dev, int si) { int i; for (i = 0; i < indio_dev->num_channels; i++) if (indio_dev->channels[i].scan_index == si) return &indio_dev->channels[i]; return NULL; } /* This turns up an awful lot */ ssize_t iio_read_const_attr(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%s\n", to_iio_const_attr(attr)->string); } EXPORT_SYMBOL(iio_read_const_attr); static int __init iio_init(void) { int ret; /* Register sysfs bus */ ret = bus_register(&iio_bus_type); if (ret < 0) { pr_err("could not register bus type\n"); goto error_nothing; } ret = alloc_chrdev_region(&iio_devt, 0, IIO_DEV_MAX, "iio"); if (ret < 0) { pr_err("failed to allocate char dev region\n"); goto error_unregister_bus_type; } iio_debugfs_dentry = debugfs_create_dir("iio", NULL); return 0; error_unregister_bus_type: bus_unregister(&iio_bus_type); error_nothing: return ret; } static void __exit iio_exit(void) { if (iio_devt) unregister_chrdev_region(iio_devt, IIO_DEV_MAX); bus_unregister(&iio_bus_type); debugfs_remove(iio_debugfs_dentry); } #if defined(CONFIG_DEBUG_FS) static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf, size_t count, loff_t *ppos) { struct iio_dev *indio_dev = file->private_data; char buf[20]; unsigned val = 0; ssize_t len; int ret; ret = indio_dev->info->debugfs_reg_access(indio_dev, indio_dev->cached_reg_addr, 0, &val); if (ret) dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__); len = snprintf(buf, sizeof(buf), "0x%X\n", val); return simple_read_from_buffer(userbuf, count, ppos, buf, len); } static ssize_t iio_debugfs_write_reg(struct file *file, const char __user *userbuf, size_t count, loff_t *ppos) { struct iio_dev *indio_dev = file->private_data; unsigned reg, val; char buf[80]; int ret; count = min_t(size_t, count, (sizeof(buf)-1)); if (copy_from_user(buf, userbuf, count)) return -EFAULT; buf[count] = 0; ret = sscanf(buf, "%i %i", ®, &val); switch (ret) { case 1: indio_dev->cached_reg_addr = reg; break; case 2: indio_dev->cached_reg_addr = reg; ret = indio_dev->info->debugfs_reg_access(indio_dev, reg, val, NULL); if (ret) { dev_err(indio_dev->dev.parent, "%s: write failed\n", __func__); return ret; } break; default: return -EINVAL; } return count; } static const struct file_operations iio_debugfs_reg_fops = { .open = simple_open, .read = iio_debugfs_read_reg, .write = iio_debugfs_write_reg, }; static void iio_device_unregister_debugfs(struct iio_dev *indio_dev) { debugfs_remove_recursive(indio_dev->debugfs_dentry); } static int iio_device_register_debugfs(struct iio_dev *indio_dev) { struct dentry *d; if (indio_dev->info->debugfs_reg_access == NULL) return 0; if (!iio_debugfs_dentry) return 0; indio_dev->debugfs_dentry = debugfs_create_dir(dev_name(&indio_dev->dev), iio_debugfs_dentry); if (indio_dev->debugfs_dentry == NULL) { dev_warn(indio_dev->dev.parent, "Failed to create debugfs directory\n"); return -EFAULT; } d = debugfs_create_file("direct_reg_access", 0644, indio_dev->debugfs_dentry, indio_dev, &iio_debugfs_reg_fops); if (!d) { iio_device_unregister_debugfs(indio_dev); return -ENOMEM; } return 0; } #else static int iio_device_register_debugfs(struct iio_dev *indio_dev) { return 0; } static void iio_device_unregister_debugfs(struct iio_dev *indio_dev) { } #endif /* CONFIG_DEBUG_FS */ static ssize_t iio_read_channel_ext_info(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); const struct iio_chan_spec_ext_info *ext_info; ext_info = &this_attr->c->ext_info[this_attr->address]; return ext_info->read(indio_dev, ext_info->private, this_attr->c, buf); } static ssize_t iio_write_channel_ext_info(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); const struct iio_chan_spec_ext_info *ext_info; ext_info = &this_attr->c->ext_info[this_attr->address]; return ext_info->write(indio_dev, ext_info->private, this_attr->c, buf, len); } ssize_t iio_enum_available_read(struct iio_dev *indio_dev, uintptr_t priv, const struct iio_chan_spec *chan, char *buf) { const struct iio_enum *e = (const struct iio_enum *)priv; unsigned int i; size_t len = 0; if (!e->num_items) return 0; for (i = 0; i < e->num_items; ++i) len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]); /* replace last space with a newline */ buf[len - 1] = '\n'; return len; } EXPORT_SYMBOL_GPL(iio_enum_available_read); ssize_t iio_enum_read(struct iio_dev *indio_dev, uintptr_t priv, const struct iio_chan_spec *chan, char *buf) { const struct iio_enum *e = (const struct iio_enum *)priv; int i; if (!e->get) return -EINVAL; i = e->get(indio_dev, chan); if (i < 0) return i; else if (i >= e->num_items) return -EINVAL; return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]); } EXPORT_SYMBOL_GPL(iio_enum_read); ssize_t iio_enum_write(struct iio_dev *indio_dev, uintptr_t priv, const struct iio_chan_spec *chan, const char *buf, size_t len) { const struct iio_enum *e = (const struct iio_enum *)priv; unsigned int i; int ret; if (!e->set) return -EINVAL; for (i = 0; i < e->num_items; i++) { if (sysfs_streq(buf, e->items[i])) break; } if (i == e->num_items) return -EINVAL; ret = e->set(indio_dev, chan, i); return ret ? ret : len; } EXPORT_SYMBOL_GPL(iio_enum_write); /** * iio_format_value() - Formats a IIO value into its string representation * @buf: The buffer to which the formatted value gets written * @type: One of the IIO_VAL_... constants. This decides how the val * and val2 parameters are formatted. * @size: Number of IIO value entries contained in vals * @vals: Pointer to the values, exact meaning depends on the * type parameter. * * Return: 0 by default, a negative number on failure or the * total number of characters written for a type that belongs * to the IIO_VAL_... constant. */ ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals) { unsigned long long tmp; bool scale_db = false; switch (type) { case IIO_VAL_INT: return sprintf(buf, "%d\n", vals[0]); case IIO_VAL_INT_PLUS_MICRO_DB: scale_db = true; case IIO_VAL_INT_PLUS_MICRO: if (vals[1] < 0) return sprintf(buf, "-%ld.%06u%s\n", abs(vals[0]), -vals[1], scale_db ? " dB" : ""); else return sprintf(buf, "%d.%06u%s\n", vals[0], vals[1], scale_db ? " dB" : ""); case IIO_VAL_INT_PLUS_NANO: if (vals[1] < 0) return sprintf(buf, "-%ld.%09u\n", abs(vals[0]), -vals[1]); else return sprintf(buf, "%d.%09u\n", vals[0], vals[1]); case IIO_VAL_FRACTIONAL: tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]); vals[1] = do_div(tmp, 1000000000LL); vals[0] = tmp; return sprintf(buf, "%d.%09u\n", vals[0], vals[1]); case IIO_VAL_FRACTIONAL_LOG2: tmp = (s64)vals[0] * 1000000000LL >> vals[1]; vals[1] = do_div(tmp, 1000000000LL); vals[0] = tmp; return sprintf(buf, "%d.%09u\n", vals[0], vals[1]); case IIO_VAL_INT_MULTIPLE: { int i; int len = 0; for (i = 0; i < size; ++i) len += snprintf(&buf[len], PAGE_SIZE - len, "%d ", vals[i]); len += snprintf(&buf[len], PAGE_SIZE - len, "\n"); return len; } default: return 0; } } static ssize_t iio_read_channel_info(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); int vals[INDIO_MAX_RAW_ELEMENTS]; int ret; int val_len = 2; if (indio_dev->info->read_raw_multi) ret = indio_dev->info->read_raw_multi(indio_dev, this_attr->c, INDIO_MAX_RAW_ELEMENTS, vals, &val_len, this_attr->address); else ret = indio_dev->info->read_raw(indio_dev, this_attr->c, &vals[0], &vals[1], this_attr->address); if (ret < 0) return ret; return iio_format_value(buf, ret, val_len, vals); } /** * iio_str_to_fixpoint() - Parse a fixed-point number from a string * @str: The string to parse * @fract_mult: Multiplier for the first decimal place, should be a power of 10 * @integer: The integer part of the number * @fract: The fractional part of the number * * Returns 0 on success, or a negative error code if the string could not be * parsed. */ int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer, int *fract) { int i = 0, f = 0; bool integer_part = true, negative = false; if (str[0] == '-') { negative = true; str++; } else if (str[0] == '+') { str++; } while (*str) { if ('0' <= *str && *str <= '9') { if (integer_part) { i = i * 10 + *str - '0'; } else { f += fract_mult * (*str - '0'); fract_mult /= 10; } } else if (*str == '\n') { if (*(str + 1) == '\0') break; else return -EINVAL; } else if (*str == '.' && integer_part) { integer_part = false; } else { return -EINVAL; } str++; } if (negative) { if (i) i = -i; else f = -f; } *integer = i; *fract = f; return 0; } EXPORT_SYMBOL_GPL(iio_str_to_fixpoint); static ssize_t iio_write_channel_info(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); int ret, fract_mult = 100000; int integer, fract; /* Assumes decimal - precision based on number of digits */ if (!indio_dev->info->write_raw) return -EINVAL; if (indio_dev->info->write_raw_get_fmt) switch (indio_dev->info->write_raw_get_fmt(indio_dev, this_attr->c, this_attr->address)) { case IIO_VAL_INT_PLUS_MICRO: fract_mult = 100000; break; case IIO_VAL_INT_PLUS_NANO: fract_mult = 100000000; break; default: return -EINVAL; } ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract); if (ret) return ret; ret = indio_dev->info->write_raw(indio_dev, this_attr->c, integer, fract, this_attr->address); if (ret) return ret; return len; } static int __iio_device_attr_init(struct device_attribute *dev_attr, const char *postfix, struct iio_chan_spec const *chan, ssize_t (*readfunc)(struct device *dev, struct device_attribute *attr, char *buf), ssize_t (*writefunc)(struct device *dev, struct device_attribute *attr, const char *buf, size_t len), enum iio_shared_by shared_by) { int ret = 0; char *name = NULL; char *full_postfix; sysfs_attr_init(&dev_attr->attr); /* Build up postfix of __postfix */ if (chan->modified && (shared_by == IIO_SEPARATE)) { if (chan->extend_name) full_postfix = kasprintf(GFP_KERNEL, "%s_%s_%s", iio_modifier_names[chan ->channel2], chan->extend_name, postfix); else full_postfix = kasprintf(GFP_KERNEL, "%s_%s", iio_modifier_names[chan ->channel2], postfix); } else { if (chan->extend_name == NULL || shared_by != IIO_SEPARATE) full_postfix = kstrdup(postfix, GFP_KERNEL); else full_postfix = kasprintf(GFP_KERNEL, "%s_%s", chan->extend_name, postfix); } if (full_postfix == NULL) return -ENOMEM; if (chan->differential) { /* Differential can not have modifier */ switch (shared_by) { case IIO_SHARED_BY_ALL: name = kasprintf(GFP_KERNEL, "%s", full_postfix); break; case IIO_SHARED_BY_DIR: name = kasprintf(GFP_KERNEL, "%s_%s", iio_direction[chan->output], full_postfix); break; case IIO_SHARED_BY_TYPE: name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s", iio_direction[chan->output], iio_chan_type_name_spec[chan->type], iio_chan_type_name_spec[chan->type], full_postfix); break; case IIO_SEPARATE: if (!chan->indexed) { WARN_ON("Differential channels must be indexed\n"); ret = -EINVAL; goto error_free_full_postfix; } name = kasprintf(GFP_KERNEL, "%s_%s%d-%s%d_%s", iio_direction[chan->output], iio_chan_type_name_spec[chan->type], chan->channel, iio_chan_type_name_spec[chan->type], chan->channel2, full_postfix); break; } } else { /* Single ended */ switch (shared_by) { case IIO_SHARED_BY_ALL: name = kasprintf(GFP_KERNEL, "%s", full_postfix); break; case IIO_SHARED_BY_DIR: name = kasprintf(GFP_KERNEL, "%s_%s", iio_direction[chan->output], full_postfix); break; case IIO_SHARED_BY_TYPE: name = kasprintf(GFP_KERNEL, "%s_%s_%s", iio_direction[chan->output], iio_chan_type_name_spec[chan->type], full_postfix); break; case IIO_SEPARATE: if (chan->indexed) name = kasprintf(GFP_KERNEL, "%s_%s%d_%s", iio_direction[chan->output], iio_chan_type_name_spec[chan->type], chan->channel, full_postfix); else name = kasprintf(GFP_KERNEL, "%s_%s_%s", iio_direction[chan->output], iio_chan_type_name_spec[chan->type], full_postfix); break; } } if (name == NULL) { ret = -ENOMEM; goto error_free_full_postfix; } dev_attr->attr.name = name; if (readfunc) { dev_attr->attr.mode |= S_IRUGO; dev_attr->show = readfunc; } if (writefunc) { dev_attr->attr.mode |= S_IWUSR; dev_attr->store = writefunc; } error_free_full_postfix: kfree(full_postfix); return ret; } static void __iio_device_attr_deinit(struct device_attribute *dev_attr) { kfree(dev_attr->attr.name); } int __iio_add_chan_devattr(const char *postfix, struct iio_chan_spec const *chan, ssize_t (*readfunc)(struct device *dev, struct device_attribute *attr, char *buf), ssize_t (*writefunc)(struct device *dev, struct device_attribute *attr, const char *buf, size_t len), u64 mask, enum iio_shared_by shared_by, struct device *dev, struct list_head *attr_list) { int ret; struct iio_dev_attr *iio_attr, *t; iio_attr = kzalloc(sizeof(*iio_attr), GFP_KERNEL); if (iio_attr == NULL) return -ENOMEM; ret = __iio_device_attr_init(&iio_attr->dev_attr, postfix, chan, readfunc, writefunc, shared_by); if (ret) goto error_iio_dev_attr_free; iio_attr->c = chan; iio_attr->address = mask; list_for_each_entry(t, attr_list, l) if (strcmp(t->dev_attr.attr.name, iio_attr->dev_attr.attr.name) == 0) { if (shared_by == IIO_SEPARATE) dev_err(dev, "tried to double register : %s\n", t->dev_attr.attr.name); ret = -EBUSY; goto error_device_attr_deinit; } list_add(&iio_attr->l, attr_list); return 0; error_device_attr_deinit: __iio_device_attr_deinit(&iio_attr->dev_attr); error_iio_dev_attr_free: kfree(iio_attr); return ret; } static int iio_device_add_info_mask_type(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, enum iio_shared_by shared_by, const long *infomask) { int i, ret, attrcount = 0; for_each_set_bit(i, infomask, sizeof(infomask)*8) { if (i >= ARRAY_SIZE(iio_chan_info_postfix)) return -EINVAL; ret = __iio_add_chan_devattr(iio_chan_info_postfix[i], chan, &iio_read_channel_info, &iio_write_channel_info, i, shared_by, &indio_dev->dev, &indio_dev->channel_attr_list); if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE)) continue; else if (ret < 0) return ret; attrcount++; } return attrcount; } static int iio_device_add_channel_sysfs(struct iio_dev *indio_dev, struct iio_chan_spec const *chan) { int ret, attrcount = 0; const struct iio_chan_spec_ext_info *ext_info; if (chan->channel < 0) return 0; ret = iio_device_add_info_mask_type(indio_dev, chan, IIO_SEPARATE, &chan->info_mask_separate); if (ret < 0) return ret; attrcount += ret; ret = iio_device_add_info_mask_type(indio_dev, chan, IIO_SHARED_BY_TYPE, &chan->info_mask_shared_by_type); if (ret < 0) return ret; attrcount += ret; ret = iio_device_add_info_mask_type(indio_dev, chan, IIO_SHARED_BY_DIR, &chan->info_mask_shared_by_dir); if (ret < 0) return ret; attrcount += ret; ret = iio_device_add_info_mask_type(indio_dev, chan, IIO_SHARED_BY_ALL, &chan->info_mask_shared_by_all); if (ret < 0) return ret; attrcount += ret; if (chan->ext_info) { unsigned int i = 0; for (ext_info = chan->ext_info; ext_info->name; ext_info++) { ret = __iio_add_chan_devattr(ext_info->name, chan, ext_info->read ? &iio_read_channel_ext_info : NULL, ext_info->write ? &iio_write_channel_ext_info : NULL, i, ext_info->shared, &indio_dev->dev, &indio_dev->channel_attr_list); i++; if (ret == -EBUSY && ext_info->shared) continue; if (ret) return ret; attrcount++; } } return attrcount; } /** * iio_free_chan_devattr_list() - Free a list of IIO device attributes * @attr_list: List of IIO device attributes * * This function frees the memory allocated for each of the IIO device * attributes in the list. */ void iio_free_chan_devattr_list(struct list_head *attr_list) { struct iio_dev_attr *p, *n; list_for_each_entry_safe(p, n, attr_list, l) { kfree(p->dev_attr.attr.name); list_del(&p->l); kfree(p); } } static ssize_t iio_show_dev_name(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); return snprintf(buf, PAGE_SIZE, "%s\n", indio_dev->name); } static DEVICE_ATTR(name, S_IRUGO, iio_show_dev_name, NULL); static int iio_device_register_sysfs(struct iio_dev *indio_dev) { int i, ret = 0, attrcount, attrn, attrcount_orig = 0; struct iio_dev_attr *p; struct attribute **attr; /* First count elements in any existing group */ if (indio_dev->info->attrs) { attr = indio_dev->info->attrs->attrs; while (*attr++ != NULL) attrcount_orig++; } attrcount = attrcount_orig; /* * New channel registration method - relies on the fact a group does * not need to be initialized if its name is NULL. */ if (indio_dev->channels) for (i = 0; i < indio_dev->num_channels; i++) { ret = iio_device_add_channel_sysfs(indio_dev, &indio_dev ->channels[i]); if (ret < 0) goto error_clear_attrs; attrcount += ret; } if (indio_dev->name) attrcount++; indio_dev->chan_attr_group.attrs = kcalloc(attrcount + 1, sizeof(indio_dev->chan_attr_group.attrs[0]), GFP_KERNEL); if (indio_dev->chan_attr_group.attrs == NULL) { ret = -ENOMEM; goto error_clear_attrs; } /* Copy across original attributes */ if (indio_dev->info->attrs) memcpy(indio_dev->chan_attr_group.attrs, indio_dev->info->attrs->attrs, sizeof(indio_dev->chan_attr_group.attrs[0]) *attrcount_orig); attrn = attrcount_orig; /* Add all elements from the list. */ list_for_each_entry(p, &indio_dev->channel_attr_list, l) indio_dev->chan_attr_group.attrs[attrn++] = &p->dev_attr.attr; if (indio_dev->name) indio_dev->chan_attr_group.attrs[attrn++] = &dev_attr_name.attr; indio_dev->groups[indio_dev->groupcounter++] = &indio_dev->chan_attr_group; return 0; error_clear_attrs: iio_free_chan_devattr_list(&indio_dev->channel_attr_list); return ret; } static void iio_device_unregister_sysfs(struct iio_dev *indio_dev) { iio_free_chan_devattr_list(&indio_dev->channel_attr_list); kfree(indio_dev->chan_attr_group.attrs); indio_dev->chan_attr_group.attrs = NULL; } static void iio_dev_release(struct device *device) { struct iio_dev *indio_dev = dev_to_iio_dev(device); if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) iio_device_unregister_trigger_consumer(indio_dev); iio_device_unregister_eventset(indio_dev); iio_device_unregister_sysfs(indio_dev); iio_buffer_put(indio_dev->buffer); ida_simple_remove(&iio_ida, indio_dev->id); kfree(indio_dev); } struct device_type iio_device_type = { .name = "iio_device", .release = iio_dev_release, }; /** * iio_device_alloc() - allocate an iio_dev from a driver * @sizeof_priv: Space to allocate for private structure. **/ struct iio_dev *iio_device_alloc(int sizeof_priv) { struct iio_dev *dev; size_t alloc_size; alloc_size = sizeof(struct iio_dev); if (sizeof_priv) { alloc_size = ALIGN(alloc_size, IIO_ALIGN); alloc_size += sizeof_priv; } /* ensure 32-byte alignment of whole construct ? */ alloc_size += IIO_ALIGN - 1; dev = kzalloc(alloc_size, GFP_KERNEL); if (dev) { dev->dev.groups = dev->groups; dev->dev.type = &iio_device_type; dev->dev.bus = &iio_bus_type; device_initialize(&dev->dev); dev_set_drvdata(&dev->dev, (void *)dev); mutex_init(&dev->mlock); mutex_init(&dev->info_exist_lock); INIT_LIST_HEAD(&dev->channel_attr_list); dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); if (dev->id < 0) { /* cannot use a dev_err as the name isn't available */ pr_err("failed to get device id\n"); kfree(dev); return NULL; } dev_set_name(&dev->dev, "iio:device%d", dev->id); INIT_LIST_HEAD(&dev->buffer_list); } return dev; } EXPORT_SYMBOL(iio_device_alloc); /** * iio_device_free() - free an iio_dev from a driver * @dev: the iio_dev associated with the device **/ void iio_device_free(struct iio_dev *dev) { if (dev) put_device(&dev->dev); } EXPORT_SYMBOL(iio_device_free); static void devm_iio_device_release(struct device *dev, void *res) { iio_device_free(*(struct iio_dev **)res); } static int devm_iio_device_match(struct device *dev, void *res, void *data) { struct iio_dev **r = res; if (!r || !*r) { WARN_ON(!r || !*r); return 0; } return *r == data; } /** * devm_iio_device_alloc - Resource-managed iio_device_alloc() * @dev: Device to allocate iio_dev for * @sizeof_priv: Space to allocate for private structure. * * Managed iio_device_alloc. iio_dev allocated with this function is * automatically freed on driver detach. * * If an iio_dev allocated with this function needs to be freed separately, * devm_iio_device_free() must be used. * * RETURNS: * Pointer to allocated iio_dev on success, NULL on failure. */ struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv) { struct iio_dev **ptr, *iio_dev; ptr = devres_alloc(devm_iio_device_release, sizeof(*ptr), GFP_KERNEL); if (!ptr) return NULL; iio_dev = iio_device_alloc(sizeof_priv); if (iio_dev) { *ptr = iio_dev; devres_add(dev, ptr); } else { devres_free(ptr); } return iio_dev; } EXPORT_SYMBOL_GPL(devm_iio_device_alloc); /** * devm_iio_device_free - Resource-managed iio_device_free() * @dev: Device this iio_dev belongs to * @iio_dev: the iio_dev associated with the device * * Free iio_dev allocated with devm_iio_device_alloc(). */ void devm_iio_device_free(struct device *dev, struct iio_dev *iio_dev) { int rc; rc = devres_release(dev, devm_iio_device_release, devm_iio_device_match, iio_dev); WARN_ON(rc); } EXPORT_SYMBOL_GPL(devm_iio_device_free); /** * iio_chrdev_open() - chrdev file open for buffer access and ioctls * @inode: Inode structure for identifying the device in the file system * @filp: File structure for iio device used to keep and later access * private data * * Return: 0 on success or -EBUSY if the device is already opened **/ static int iio_chrdev_open(struct inode *inode, struct file *filp) { struct iio_dev *indio_dev = container_of(inode->i_cdev, struct iio_dev, chrdev); if (test_and_set_bit(IIO_BUSY_BIT_POS, &indio_dev->flags)) return -EBUSY; iio_device_get(indio_dev); filp->private_data = indio_dev; return 0; } /** * iio_chrdev_release() - chrdev file close buffer access and ioctls * @inode: Inode structure pointer for the char device * @filp: File structure pointer for the char device * * Return: 0 for successful release */ static int iio_chrdev_release(struct inode *inode, struct file *filp) { struct iio_dev *indio_dev = container_of(inode->i_cdev, struct iio_dev, chrdev); clear_bit(IIO_BUSY_BIT_POS, &indio_dev->flags); iio_device_put(indio_dev); return 0; } /* Somewhat of a cross file organization violation - ioctls here are actually * event related */ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { struct iio_dev *indio_dev = filp->private_data; int __user *ip = (int __user *)arg; int fd; if (!indio_dev->info) return -ENODEV; if (cmd == IIO_GET_EVENT_FD_IOCTL) { fd = iio_event_getfd(indio_dev); if (fd < 0) return fd; if (copy_to_user(ip, &fd, sizeof(fd))) return -EFAULT; return 0; } return -EINVAL; } static const struct file_operations iio_buffer_fileops = { .read = iio_buffer_read_first_n_outer_addr, .release = iio_chrdev_release, .open = iio_chrdev_open, .poll = iio_buffer_poll_addr, .owner = THIS_MODULE, .llseek = noop_llseek, .unlocked_ioctl = iio_ioctl, .compat_ioctl = iio_ioctl, }; static int iio_check_unique_scan_index(struct iio_dev *indio_dev) { int i, j; const struct iio_chan_spec *channels = indio_dev->channels; if (!(indio_dev->modes & INDIO_ALL_BUFFER_MODES)) return 0; for (i = 0; i < indio_dev->num_channels - 1; i++) { if (channels[i].scan_index < 0) continue; for (j = i + 1; j < indio_dev->num_channels; j++) if (channels[i].scan_index == channels[j].scan_index) { dev_err(&indio_dev->dev, "Duplicate scan index %d\n", channels[i].scan_index); return -EINVAL; } } return 0; } static const struct iio_buffer_setup_ops noop_ring_setup_ops; /** * iio_device_register() - register a device with the IIO subsystem * @indio_dev: Device structure filled by the device driver **/ int iio_device_register(struct iio_dev *indio_dev) { int ret; /* If the calling driver did not initialize of_node, do it here */ if (!indio_dev->dev.of_node && indio_dev->dev.parent) indio_dev->dev.of_node = indio_dev->dev.parent->of_node; ret = iio_check_unique_scan_index(indio_dev); if (ret < 0) return ret; /* configure elements for the chrdev */ indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id); ret = iio_device_register_debugfs(indio_dev); if (ret) { dev_err(indio_dev->dev.parent, "Failed to register debugfs interfaces\n"); return ret; } ret = iio_buffer_alloc_sysfs_and_mask(indio_dev); if (ret) { dev_err(indio_dev->dev.parent, "Failed to create buffer sysfs interfaces\n"); goto error_unreg_debugfs; } ret = iio_device_register_sysfs(indio_dev); if (ret) { dev_err(indio_dev->dev.parent, "Failed to register sysfs interfaces\n"); goto error_buffer_free_sysfs; } ret = iio_device_register_eventset(indio_dev); if (ret) { dev_err(indio_dev->dev.parent, "Failed to register event set\n"); goto error_free_sysfs; } if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) iio_device_register_trigger_consumer(indio_dev); if ((indio_dev->modes & INDIO_ALL_BUFFER_MODES) && indio_dev->setup_ops == NULL) indio_dev->setup_ops = &noop_ring_setup_ops; cdev_init(&indio_dev->chrdev, &iio_buffer_fileops); indio_dev->chrdev.owner = indio_dev->info->driver_module; indio_dev->chrdev.kobj.parent = &indio_dev->dev.kobj; ret = cdev_add(&indio_dev->chrdev, indio_dev->dev.devt, 1); if (ret < 0) goto error_unreg_eventset; ret = device_add(&indio_dev->dev); if (ret < 0) goto error_cdev_del; return 0; error_cdev_del: cdev_del(&indio_dev->chrdev); error_unreg_eventset: iio_device_unregister_eventset(indio_dev); error_free_sysfs: iio_device_unregister_sysfs(indio_dev); error_buffer_free_sysfs: iio_buffer_free_sysfs_and_mask(indio_dev); error_unreg_debugfs: iio_device_unregister_debugfs(indio_dev); return ret; } EXPORT_SYMBOL(iio_device_register); /** * iio_device_unregister() - unregister a device from the IIO subsystem * @indio_dev: Device structure representing the device. **/ void iio_device_unregister(struct iio_dev *indio_dev) { mutex_lock(&indio_dev->info_exist_lock); device_del(&indio_dev->dev); if (indio_dev->chrdev.dev) cdev_del(&indio_dev->chrdev); iio_device_unregister_debugfs(indio_dev); iio_disable_all_buffers(indio_dev); indio_dev->info = NULL; iio_device_wakeup_eventset(indio_dev); iio_buffer_wakeup_poll(indio_dev); mutex_unlock(&indio_dev->info_exist_lock); iio_buffer_free_sysfs_and_mask(indio_dev); } EXPORT_SYMBOL(iio_device_unregister); static void devm_iio_device_unreg(struct device *dev, void *res) { iio_device_unregister(*(struct iio_dev **)res); } /** * devm_iio_device_register - Resource-managed iio_device_register() * @dev: Device to allocate iio_dev for * @indio_dev: Device structure filled by the device driver * * Managed iio_device_register. The IIO device registered with this * function is automatically unregistered on driver detach. This function * calls iio_device_register() internally. Refer to that function for more * information. * * If an iio_dev registered with this function needs to be unregistered * separately, devm_iio_device_unregister() must be used. * * RETURNS: * 0 on success, negative error number on failure. */ int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev) { struct iio_dev **ptr; int ret; ptr = devres_alloc(devm_iio_device_unreg, sizeof(*ptr), GFP_KERNEL); if (!ptr) return -ENOMEM; *ptr = indio_dev; ret = iio_device_register(indio_dev); if (!ret) devres_add(dev, ptr); else devres_free(ptr); return ret; } EXPORT_SYMBOL_GPL(devm_iio_device_register); /** * devm_iio_device_unregister - Resource-managed iio_device_unregister() * @dev: Device this iio_dev belongs to * @indio_dev: the iio_dev associated with the device * * Unregister iio_dev registered with devm_iio_device_register(). */ void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev) { int rc; rc = devres_release(dev, devm_iio_device_unreg, devm_iio_device_match, indio_dev); WARN_ON(rc); } EXPORT_SYMBOL_GPL(devm_iio_device_unregister); subsys_initcall(iio_init); module_exit(iio_exit); MODULE_AUTHOR("Jonathan Cameron "); MODULE_DESCRIPTION("Industrial I/O core"); MODULE_LICENSE("GPL");