| /* The industrial I/O core in kernel channel mapping |
| * |
| * Copyright (c) 2011 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. |
| */ |
| #include <linux/err.h> |
| #include <linux/export.h> |
| #include <linux/slab.h> |
| #include <linux/mutex.h> |
| #include <linux/of.h> |
| |
| #include <linux/iio/iio.h> |
| #include "iio_core.h" |
| #include <linux/iio/machine.h> |
| #include <linux/iio/driver.h> |
| #include <linux/iio/consumer.h> |
| |
| struct iio_map_internal { |
| struct iio_dev *indio_dev; |
| struct iio_map *map; |
| struct list_head l; |
| }; |
| |
| static LIST_HEAD(iio_map_list); |
| static DEFINE_MUTEX(iio_map_list_lock); |
| |
| int iio_map_array_register(struct iio_dev *indio_dev, struct iio_map *maps) |
| { |
| int i = 0, ret = 0; |
| struct iio_map_internal *mapi; |
| |
| if (maps == NULL) |
| return 0; |
| |
| mutex_lock(&iio_map_list_lock); |
| while (maps[i].consumer_dev_name != NULL) { |
| mapi = kzalloc(sizeof(*mapi), GFP_KERNEL); |
| if (mapi == NULL) { |
| ret = -ENOMEM; |
| goto error_ret; |
| } |
| mapi->map = &maps[i]; |
| mapi->indio_dev = indio_dev; |
| list_add(&mapi->l, &iio_map_list); |
| i++; |
| } |
| error_ret: |
| mutex_unlock(&iio_map_list_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_map_array_register); |
| |
| |
| /* |
| * Remove all map entries associated with the given iio device |
| */ |
| int iio_map_array_unregister(struct iio_dev *indio_dev) |
| { |
| int ret = -ENODEV; |
| struct iio_map_internal *mapi; |
| struct list_head *pos, *tmp; |
| |
| mutex_lock(&iio_map_list_lock); |
| list_for_each_safe(pos, tmp, &iio_map_list) { |
| mapi = list_entry(pos, struct iio_map_internal, l); |
| if (indio_dev == mapi->indio_dev) { |
| list_del(&mapi->l); |
| kfree(mapi); |
| ret = 0; |
| } |
| } |
| mutex_unlock(&iio_map_list_lock); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_map_array_unregister); |
| |
| static const struct iio_chan_spec |
| *iio_chan_spec_from_name(const struct iio_dev *indio_dev, const char *name) |
| { |
| int i; |
| const struct iio_chan_spec *chan = NULL; |
| |
| for (i = 0; i < indio_dev->num_channels; i++) |
| if (indio_dev->channels[i].datasheet_name && |
| strcmp(name, indio_dev->channels[i].datasheet_name) == 0) { |
| chan = &indio_dev->channels[i]; |
| break; |
| } |
| return chan; |
| } |
| |
| #ifdef CONFIG_OF |
| |
| static int iio_dev_node_match(struct device *dev, void *data) |
| { |
| return dev->of_node == data && dev->type == &iio_device_type; |
| } |
| |
| static int __of_iio_channel_get(struct iio_channel *channel, |
| struct device_node *np, int index) |
| { |
| struct device *idev; |
| struct iio_dev *indio_dev; |
| int err; |
| struct of_phandle_args iiospec; |
| |
| err = of_parse_phandle_with_args(np, "io-channels", |
| "#io-channel-cells", |
| index, &iiospec); |
| if (err) |
| return err; |
| |
| idev = bus_find_device(&iio_bus_type, NULL, iiospec.np, |
| iio_dev_node_match); |
| of_node_put(iiospec.np); |
| if (idev == NULL) |
| return -EPROBE_DEFER; |
| |
| indio_dev = dev_to_iio_dev(idev); |
| channel->indio_dev = indio_dev; |
| index = iiospec.args_count ? iiospec.args[0] : 0; |
| if (index >= indio_dev->num_channels) { |
| err = -EINVAL; |
| goto err_put; |
| } |
| channel->channel = &indio_dev->channels[index]; |
| |
| return 0; |
| |
| err_put: |
| iio_device_put(indio_dev); |
| return err; |
| } |
| |
| static struct iio_channel *of_iio_channel_get(struct device_node *np, int index) |
| { |
| struct iio_channel *channel; |
| int err; |
| |
| if (index < 0) |
| return ERR_PTR(-EINVAL); |
| |
| channel = kzalloc(sizeof(*channel), GFP_KERNEL); |
| if (channel == NULL) |
| return ERR_PTR(-ENOMEM); |
| |
| err = __of_iio_channel_get(channel, np, index); |
| if (err) |
| goto err_free_channel; |
| |
| return channel; |
| |
| err_free_channel: |
| kfree(channel); |
| return ERR_PTR(err); |
| } |
| |
| static struct iio_channel *of_iio_channel_get_by_name(struct device_node *np, |
| const char *name) |
| { |
| struct iio_channel *chan = NULL; |
| |
| /* Walk up the tree of devices looking for a matching iio channel */ |
| while (np) { |
| int index = 0; |
| |
| /* |
| * For named iio channels, first look up the name in the |
| * "io-channel-names" property. If it cannot be found, the |
| * index will be an error code, and of_iio_channel_get() |
| * will fail. |
| */ |
| if (name) |
| index = of_property_match_string(np, "io-channel-names", |
| name); |
| chan = of_iio_channel_get(np, index); |
| if (!IS_ERR(chan)) |
| break; |
| else if (name && index >= 0) { |
| pr_err("ERROR: could not get IIO channel %s:%s(%i)\n", |
| np->full_name, name ? name : "", index); |
| return chan; |
| } |
| |
| /* |
| * No matching IIO channel found on this node. |
| * If the parent node has a "io-channel-ranges" property, |
| * then we can try one of its channels. |
| */ |
| np = np->parent; |
| if (np && !of_get_property(np, "io-channel-ranges", NULL)) |
| break; |
| } |
| return chan; |
| } |
| |
| static struct iio_channel *of_iio_channel_get_all(struct device *dev) |
| { |
| struct iio_channel *chans; |
| int i, mapind, nummaps = 0; |
| int ret; |
| |
| do { |
| ret = of_parse_phandle_with_args(dev->of_node, |
| "io-channels", |
| "#io-channel-cells", |
| nummaps, NULL); |
| if (ret < 0) |
| break; |
| } while (++nummaps); |
| |
| if (nummaps == 0) /* no error, return NULL to search map table */ |
| return NULL; |
| |
| /* NULL terminated array to save passing size */ |
| chans = kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL); |
| if (chans == NULL) |
| return ERR_PTR(-ENOMEM); |
| |
| /* Search for OF matches */ |
| for (mapind = 0; mapind < nummaps; mapind++) { |
| ret = __of_iio_channel_get(&chans[mapind], dev->of_node, |
| mapind); |
| if (ret) |
| goto error_free_chans; |
| } |
| return chans; |
| |
| error_free_chans: |
| for (i = 0; i < mapind; i++) |
| iio_device_put(chans[i].indio_dev); |
| kfree(chans); |
| return ERR_PTR(ret); |
| } |
| |
| #else /* CONFIG_OF */ |
| |
| static inline struct iio_channel * |
| of_iio_channel_get_by_name(struct device_node *np, const char *name) |
| { |
| return NULL; |
| } |
| |
| static inline struct iio_channel *of_iio_channel_get_all(struct device *dev) |
| { |
| return NULL; |
| } |
| |
| #endif /* CONFIG_OF */ |
| |
| static struct iio_channel *iio_channel_get_sys(const char *name, |
| const char *channel_name) |
| { |
| struct iio_map_internal *c_i = NULL, *c = NULL; |
| struct iio_channel *channel; |
| int err; |
| |
| if (name == NULL && channel_name == NULL) |
| return ERR_PTR(-ENODEV); |
| |
| /* first find matching entry the channel map */ |
| mutex_lock(&iio_map_list_lock); |
| list_for_each_entry(c_i, &iio_map_list, l) { |
| if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) || |
| (channel_name && |
| strcmp(channel_name, c_i->map->consumer_channel) != 0)) |
| continue; |
| c = c_i; |
| iio_device_get(c->indio_dev); |
| break; |
| } |
| mutex_unlock(&iio_map_list_lock); |
| if (c == NULL) |
| return ERR_PTR(-ENODEV); |
| |
| channel = kzalloc(sizeof(*channel), GFP_KERNEL); |
| if (channel == NULL) { |
| err = -ENOMEM; |
| goto error_no_mem; |
| } |
| |
| channel->indio_dev = c->indio_dev; |
| |
| if (c->map->adc_channel_label) { |
| channel->channel = |
| iio_chan_spec_from_name(channel->indio_dev, |
| c->map->adc_channel_label); |
| |
| if (channel->channel == NULL) { |
| err = -EINVAL; |
| goto error_no_chan; |
| } |
| } |
| |
| return channel; |
| |
| error_no_chan: |
| kfree(channel); |
| error_no_mem: |
| iio_device_put(c->indio_dev); |
| return ERR_PTR(err); |
| } |
| |
| struct iio_channel *iio_channel_get(struct device *dev, |
| const char *channel_name) |
| { |
| const char *name = dev ? dev_name(dev) : NULL; |
| struct iio_channel *channel; |
| |
| if (dev) { |
| channel = of_iio_channel_get_by_name(dev->of_node, |
| channel_name); |
| if ((channel != NULL) && (!IS_ERR(channel))) |
| return channel; |
| } |
| return iio_channel_get_sys(name, channel_name); |
| } |
| EXPORT_SYMBOL_GPL(iio_channel_get); |
| |
| void iio_channel_release(struct iio_channel *channel) |
| { |
| iio_device_put(channel->indio_dev); |
| kfree(channel); |
| } |
| EXPORT_SYMBOL_GPL(iio_channel_release); |
| |
| struct iio_channel *iio_channel_get_all(struct device *dev) |
| { |
| const char *name; |
| struct iio_channel *chans; |
| struct iio_map_internal *c = NULL; |
| int nummaps = 0; |
| int mapind = 0; |
| int i, ret; |
| |
| if (dev == NULL) |
| return ERR_PTR(-EINVAL); |
| |
| chans = of_iio_channel_get_all(dev); |
| if (chans) |
| return chans; |
| |
| name = dev_name(dev); |
| |
| mutex_lock(&iio_map_list_lock); |
| /* first count the matching maps */ |
| list_for_each_entry(c, &iio_map_list, l) |
| if (name && strcmp(name, c->map->consumer_dev_name) != 0) |
| continue; |
| else |
| nummaps++; |
| |
| if (nummaps == 0) { |
| ret = -ENODEV; |
| goto error_ret; |
| } |
| |
| /* NULL terminated array to save passing size */ |
| chans = kzalloc(sizeof(*chans)*(nummaps + 1), GFP_KERNEL); |
| if (chans == NULL) { |
| ret = -ENOMEM; |
| goto error_ret; |
| } |
| |
| /* for each map fill in the chans element */ |
| list_for_each_entry(c, &iio_map_list, l) { |
| if (name && strcmp(name, c->map->consumer_dev_name) != 0) |
| continue; |
| chans[mapind].indio_dev = c->indio_dev; |
| chans[mapind].data = c->map->consumer_data; |
| chans[mapind].channel = |
| iio_chan_spec_from_name(chans[mapind].indio_dev, |
| c->map->adc_channel_label); |
| if (chans[mapind].channel == NULL) { |
| ret = -EINVAL; |
| goto error_free_chans; |
| } |
| iio_device_get(chans[mapind].indio_dev); |
| mapind++; |
| } |
| if (mapind == 0) { |
| ret = -ENODEV; |
| goto error_free_chans; |
| } |
| mutex_unlock(&iio_map_list_lock); |
| |
| return chans; |
| |
| error_free_chans: |
| for (i = 0; i < nummaps; i++) |
| iio_device_put(chans[i].indio_dev); |
| kfree(chans); |
| error_ret: |
| mutex_unlock(&iio_map_list_lock); |
| |
| return ERR_PTR(ret); |
| } |
| EXPORT_SYMBOL_GPL(iio_channel_get_all); |
| |
| void iio_channel_release_all(struct iio_channel *channels) |
| { |
| struct iio_channel *chan = &channels[0]; |
| |
| while (chan->indio_dev) { |
| iio_device_put(chan->indio_dev); |
| chan++; |
| } |
| kfree(channels); |
| } |
| EXPORT_SYMBOL_GPL(iio_channel_release_all); |
| |
| static int iio_channel_read(struct iio_channel *chan, int *val, int *val2, |
| enum iio_chan_info_enum info) |
| { |
| int unused; |
| |
| if (val2 == NULL) |
| val2 = &unused; |
| |
| return chan->indio_dev->info->read_raw(chan->indio_dev, chan->channel, |
| val, val2, info); |
| } |
| |
| int iio_read_channel_raw(struct iio_channel *chan, int *val) |
| { |
| int ret; |
| |
| mutex_lock(&chan->indio_dev->info_exist_lock); |
| if (chan->indio_dev->info == NULL) { |
| ret = -ENODEV; |
| goto err_unlock; |
| } |
| |
| ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW); |
| err_unlock: |
| mutex_unlock(&chan->indio_dev->info_exist_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_read_channel_raw); |
| |
| static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan, |
| int raw, int *processed, unsigned int scale) |
| { |
| int scale_type, scale_val, scale_val2, offset; |
| s64 raw64 = raw; |
| int ret; |
| |
| ret = iio_channel_read(chan, &offset, NULL, IIO_CHAN_INFO_OFFSET); |
| if (ret >= 0) |
| raw64 += offset; |
| |
| scale_type = iio_channel_read(chan, &scale_val, &scale_val2, |
| IIO_CHAN_INFO_SCALE); |
| if (scale_type < 0) |
| return scale_type; |
| |
| switch (scale_type) { |
| case IIO_VAL_INT: |
| *processed = raw64 * scale_val; |
| break; |
| case IIO_VAL_INT_PLUS_MICRO: |
| if (scale_val2 < 0) |
| *processed = -raw64 * scale_val; |
| else |
| *processed = raw64 * scale_val; |
| *processed += div_s64(raw64 * (s64)scale_val2 * scale, |
| 1000000LL); |
| break; |
| case IIO_VAL_INT_PLUS_NANO: |
| if (scale_val2 < 0) |
| *processed = -raw64 * scale_val; |
| else |
| *processed = raw64 * scale_val; |
| *processed += div_s64(raw64 * (s64)scale_val2 * scale, |
| 1000000000LL); |
| break; |
| case IIO_VAL_FRACTIONAL: |
| *processed = div_s64(raw64 * (s64)scale_val * scale, |
| scale_val2); |
| break; |
| case IIO_VAL_FRACTIONAL_LOG2: |
| *processed = (raw64 * (s64)scale_val * scale) >> scale_val2; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| int iio_convert_raw_to_processed(struct iio_channel *chan, int raw, |
| int *processed, unsigned int scale) |
| { |
| int ret; |
| |
| mutex_lock(&chan->indio_dev->info_exist_lock); |
| if (chan->indio_dev->info == NULL) { |
| ret = -ENODEV; |
| goto err_unlock; |
| } |
| |
| ret = iio_convert_raw_to_processed_unlocked(chan, raw, processed, |
| scale); |
| err_unlock: |
| mutex_unlock(&chan->indio_dev->info_exist_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed); |
| |
| int iio_read_channel_processed(struct iio_channel *chan, int *val) |
| { |
| int ret; |
| |
| mutex_lock(&chan->indio_dev->info_exist_lock); |
| if (chan->indio_dev->info == NULL) { |
| ret = -ENODEV; |
| goto err_unlock; |
| } |
| |
| if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_PROCESSED)) { |
| ret = iio_channel_read(chan, val, NULL, |
| IIO_CHAN_INFO_PROCESSED); |
| } else { |
| ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW); |
| if (ret < 0) |
| goto err_unlock; |
| ret = iio_convert_raw_to_processed_unlocked(chan, *val, val, 1); |
| } |
| |
| err_unlock: |
| mutex_unlock(&chan->indio_dev->info_exist_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_read_channel_processed); |
| |
| int iio_read_channel_raw_dual(struct iio_channel *chan, int *val, int *val2) |
| { |
| int ret; |
| |
| mutex_lock(&chan->indio_dev->info_exist_lock); |
| if (chan->indio_dev->info == NULL) { |
| ret = -ENODEV; |
| goto err_unlock; |
| } |
| |
| if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_RAW_DUAL)) |
| ret = iio_channel_read(chan, val, val2, IIO_CHAN_INFO_RAW_DUAL); |
| else |
| ret = -ENXIO; |
| |
| err_unlock: |
| mutex_unlock(&chan->indio_dev->info_exist_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_read_channel_raw_dual); |
| |
| int iio_read_channel_processed_dual(struct iio_channel *chan, int *val, |
| int *val2) |
| { |
| int ret; |
| |
| mutex_lock(&chan->indio_dev->info_exist_lock); |
| if (chan->indio_dev->info == NULL) { |
| ret = -ENODEV; |
| goto err_unlock; |
| } |
| |
| if (iio_channel_has_info(chan->channel, IIO_CHAN_INFO_PROCESSED_DUAL)) { |
| ret = iio_channel_read(chan, val, val2, |
| IIO_CHAN_INFO_PROCESSED_DUAL); |
| } else { |
| ret = iio_channel_read(chan, val, val2, IIO_CHAN_INFO_RAW_DUAL); |
| if (ret < 0) |
| goto err_unlock; |
| ret = iio_convert_raw_to_processed_unlocked(chan, *val, val, 1); |
| if (ret < 0) |
| goto err_unlock; |
| ret = iio_convert_raw_to_processed_unlocked(chan, *val2, val2, |
| 1); |
| } |
| |
| err_unlock: |
| mutex_unlock(&chan->indio_dev->info_exist_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_read_channel_processed_dual); |
| |
| int iio_read_channel_scale(struct iio_channel *chan, int *val, int *val2) |
| { |
| int ret; |
| |
| mutex_lock(&chan->indio_dev->info_exist_lock); |
| if (chan->indio_dev->info == NULL) { |
| ret = -ENODEV; |
| goto err_unlock; |
| } |
| |
| ret = iio_channel_read(chan, val, val2, IIO_CHAN_INFO_SCALE); |
| err_unlock: |
| mutex_unlock(&chan->indio_dev->info_exist_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_read_channel_scale); |
| |
| int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type) |
| { |
| int ret = 0; |
| /* Need to verify underlying driver has not gone away */ |
| |
| mutex_lock(&chan->indio_dev->info_exist_lock); |
| if (chan->indio_dev->info == NULL) { |
| ret = -ENODEV; |
| goto err_unlock; |
| } |
| |
| *type = chan->channel->type; |
| err_unlock: |
| mutex_unlock(&chan->indio_dev->info_exist_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_get_channel_type); |