| /* 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. |
| * |
| * Handling of buffer allocation / resizing. |
| * |
| * |
| * Things to look at here. |
| * - Better memory allocation techniques? |
| * - Alternative access techniques? |
| */ |
| #include <linux/kernel.h> |
| #include <linux/export.h> |
| #include <linux/device.h> |
| #include <linux/fs.h> |
| #include <linux/cdev.h> |
| #include <linux/slab.h> |
| #include <linux/poll.h> |
| |
| #include "iio.h" |
| #include "iio_core.h" |
| #include "sysfs.h" |
| #include "buffer.h" |
| |
| static const char * const iio_endian_prefix[] = { |
| [IIO_BE] = "be", |
| [IIO_LE] = "le", |
| }; |
| |
| /** |
| * iio_buffer_read_first_n_outer() - chrdev read for buffer access |
| * |
| * This function relies on all buffer implementations having an |
| * iio_buffer as their first element. |
| **/ |
| ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf, |
| size_t n, loff_t *f_ps) |
| { |
| struct iio_dev *indio_dev = filp->private_data; |
| struct iio_buffer *rb = indio_dev->buffer; |
| |
| if (!rb || !rb->access->read_first_n) |
| return -EINVAL; |
| return rb->access->read_first_n(rb, n, buf); |
| } |
| |
| /** |
| * iio_buffer_poll() - poll the buffer to find out if it has data |
| */ |
| unsigned int iio_buffer_poll(struct file *filp, |
| struct poll_table_struct *wait) |
| { |
| struct iio_dev *indio_dev = filp->private_data; |
| struct iio_buffer *rb = indio_dev->buffer; |
| |
| poll_wait(filp, &rb->pollq, wait); |
| if (rb->stufftoread) |
| return POLLIN | POLLRDNORM; |
| /* need a way of knowing if there may be enough data... */ |
| return 0; |
| } |
| |
| void iio_buffer_init(struct iio_buffer *buffer) |
| { |
| INIT_LIST_HEAD(&buffer->demux_list); |
| init_waitqueue_head(&buffer->pollq); |
| } |
| EXPORT_SYMBOL(iio_buffer_init); |
| |
| static ssize_t iio_show_scan_index(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| return sprintf(buf, "%u\n", to_iio_dev_attr(attr)->c->scan_index); |
| } |
| |
| static ssize_t iio_show_fixed_type(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| u8 type = this_attr->c->scan_type.endianness; |
| |
| if (type == IIO_CPU) { |
| #ifdef __LITTLE_ENDIAN |
| type = IIO_LE; |
| #else |
| type = IIO_BE; |
| #endif |
| } |
| return sprintf(buf, "%s:%c%d/%d>>%u\n", |
| iio_endian_prefix[type], |
| this_attr->c->scan_type.sign, |
| this_attr->c->scan_type.realbits, |
| this_attr->c->scan_type.storagebits, |
| this_attr->c->scan_type.shift); |
| } |
| |
| static ssize_t iio_scan_el_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| int ret; |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| |
| ret = test_bit(to_iio_dev_attr(attr)->address, |
| indio_dev->buffer->scan_mask); |
| |
| return sprintf(buf, "%d\n", ret); |
| } |
| |
| static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit) |
| { |
| clear_bit(bit, buffer->scan_mask); |
| return 0; |
| } |
| |
| static ssize_t iio_scan_el_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t len) |
| { |
| int ret; |
| bool state; |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct iio_buffer *buffer = indio_dev->buffer; |
| struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| |
| ret = strtobool(buf, &state); |
| if (ret < 0) |
| return ret; |
| mutex_lock(&indio_dev->mlock); |
| if (iio_buffer_enabled(indio_dev)) { |
| ret = -EBUSY; |
| goto error_ret; |
| } |
| ret = iio_scan_mask_query(indio_dev, buffer, this_attr->address); |
| if (ret < 0) |
| goto error_ret; |
| if (!state && ret) { |
| ret = iio_scan_mask_clear(buffer, this_attr->address); |
| if (ret) |
| goto error_ret; |
| } else if (state && !ret) { |
| ret = iio_scan_mask_set(indio_dev, buffer, this_attr->address); |
| if (ret) |
| goto error_ret; |
| } |
| |
| error_ret: |
| mutex_unlock(&indio_dev->mlock); |
| |
| return ret < 0 ? ret : len; |
| |
| } |
| |
| static ssize_t iio_scan_el_ts_show(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| return sprintf(buf, "%d\n", indio_dev->buffer->scan_timestamp); |
| } |
| |
| static ssize_t iio_scan_el_ts_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t len) |
| { |
| int ret; |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| bool state; |
| |
| ret = strtobool(buf, &state); |
| if (ret < 0) |
| return ret; |
| |
| mutex_lock(&indio_dev->mlock); |
| if (iio_buffer_enabled(indio_dev)) { |
| ret = -EBUSY; |
| goto error_ret; |
| } |
| indio_dev->buffer->scan_timestamp = state; |
| error_ret: |
| mutex_unlock(&indio_dev->mlock); |
| |
| return ret ? ret : len; |
| } |
| |
| static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev, |
| const struct iio_chan_spec *chan) |
| { |
| int ret, attrcount = 0; |
| struct iio_buffer *buffer = indio_dev->buffer; |
| |
| ret = __iio_add_chan_devattr("index", |
| chan, |
| &iio_show_scan_index, |
| NULL, |
| 0, |
| 0, |
| &indio_dev->dev, |
| &buffer->scan_el_dev_attr_list); |
| if (ret) |
| goto error_ret; |
| attrcount++; |
| ret = __iio_add_chan_devattr("type", |
| chan, |
| &iio_show_fixed_type, |
| NULL, |
| 0, |
| 0, |
| &indio_dev->dev, |
| &buffer->scan_el_dev_attr_list); |
| if (ret) |
| goto error_ret; |
| attrcount++; |
| if (chan->type != IIO_TIMESTAMP) |
| ret = __iio_add_chan_devattr("en", |
| chan, |
| &iio_scan_el_show, |
| &iio_scan_el_store, |
| chan->scan_index, |
| 0, |
| &indio_dev->dev, |
| &buffer->scan_el_dev_attr_list); |
| else |
| ret = __iio_add_chan_devattr("en", |
| chan, |
| &iio_scan_el_ts_show, |
| &iio_scan_el_ts_store, |
| chan->scan_index, |
| 0, |
| &indio_dev->dev, |
| &buffer->scan_el_dev_attr_list); |
| attrcount++; |
| ret = attrcount; |
| error_ret: |
| return ret; |
| } |
| |
| static void iio_buffer_remove_and_free_scan_dev_attr(struct iio_dev *indio_dev, |
| struct iio_dev_attr *p) |
| { |
| kfree(p->dev_attr.attr.name); |
| kfree(p); |
| } |
| |
| static void __iio_buffer_attr_cleanup(struct iio_dev *indio_dev) |
| { |
| struct iio_dev_attr *p, *n; |
| struct iio_buffer *buffer = indio_dev->buffer; |
| |
| list_for_each_entry_safe(p, n, |
| &buffer->scan_el_dev_attr_list, l) |
| iio_buffer_remove_and_free_scan_dev_attr(indio_dev, p); |
| } |
| |
| static const char * const iio_scan_elements_group_name = "scan_elements"; |
| |
| int iio_buffer_register(struct iio_dev *indio_dev, |
| const struct iio_chan_spec *channels, |
| int num_channels) |
| { |
| struct iio_dev_attr *p; |
| struct attribute **attr; |
| struct iio_buffer *buffer = indio_dev->buffer; |
| int ret, i, attrn, attrcount, attrcount_orig = 0; |
| |
| if (buffer->attrs) |
| indio_dev->groups[indio_dev->groupcounter++] = buffer->attrs; |
| |
| if (buffer->scan_el_attrs != NULL) { |
| attr = buffer->scan_el_attrs->attrs; |
| while (*attr++ != NULL) |
| attrcount_orig++; |
| } |
| attrcount = attrcount_orig; |
| INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); |
| if (channels) { |
| /* new magic */ |
| for (i = 0; i < num_channels; i++) { |
| /* Establish necessary mask length */ |
| if (channels[i].scan_index > |
| (int)indio_dev->masklength - 1) |
| indio_dev->masklength |
| = indio_dev->channels[i].scan_index + 1; |
| |
| ret = iio_buffer_add_channel_sysfs(indio_dev, |
| &channels[i]); |
| if (ret < 0) |
| goto error_cleanup_dynamic; |
| attrcount += ret; |
| if (channels[i].type == IIO_TIMESTAMP) |
| indio_dev->scan_index_timestamp = |
| channels[i].scan_index; |
| } |
| if (indio_dev->masklength && buffer->scan_mask == NULL) { |
| buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), |
| sizeof(*buffer->scan_mask), |
| GFP_KERNEL); |
| if (buffer->scan_mask == NULL) { |
| ret = -ENOMEM; |
| goto error_cleanup_dynamic; |
| } |
| } |
| } |
| |
| buffer->scan_el_group.name = iio_scan_elements_group_name; |
| |
| buffer->scan_el_group.attrs = kcalloc(attrcount + 1, |
| sizeof(buffer->scan_el_group.attrs[0]), |
| GFP_KERNEL); |
| if (buffer->scan_el_group.attrs == NULL) { |
| ret = -ENOMEM; |
| goto error_free_scan_mask; |
| } |
| if (buffer->scan_el_attrs) |
| memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs, |
| sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig); |
| attrn = attrcount_orig; |
| |
| list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l) |
| buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr; |
| indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group; |
| |
| return 0; |
| |
| error_free_scan_mask: |
| kfree(buffer->scan_mask); |
| error_cleanup_dynamic: |
| __iio_buffer_attr_cleanup(indio_dev); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL(iio_buffer_register); |
| |
| void iio_buffer_unregister(struct iio_dev *indio_dev) |
| { |
| kfree(indio_dev->buffer->scan_mask); |
| kfree(indio_dev->buffer->scan_el_group.attrs); |
| __iio_buffer_attr_cleanup(indio_dev); |
| } |
| EXPORT_SYMBOL(iio_buffer_unregister); |
| |
| ssize_t iio_buffer_read_length(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct iio_buffer *buffer = indio_dev->buffer; |
| |
| if (buffer->access->get_length) |
| return sprintf(buf, "%d\n", |
| buffer->access->get_length(buffer)); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(iio_buffer_read_length); |
| |
| ssize_t iio_buffer_write_length(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t len) |
| { |
| int ret; |
| ulong val; |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct iio_buffer *buffer = indio_dev->buffer; |
| |
| ret = strict_strtoul(buf, 10, &val); |
| if (ret) |
| return ret; |
| |
| if (buffer->access->get_length) |
| if (val == buffer->access->get_length(buffer)) |
| return len; |
| |
| mutex_lock(&indio_dev->mlock); |
| if (iio_buffer_enabled(indio_dev)) { |
| ret = -EBUSY; |
| } else { |
| if (buffer->access->set_length) |
| buffer->access->set_length(buffer, val); |
| ret = 0; |
| } |
| mutex_unlock(&indio_dev->mlock); |
| |
| return ret ? ret : len; |
| } |
| EXPORT_SYMBOL(iio_buffer_write_length); |
| |
| ssize_t iio_buffer_store_enable(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, |
| size_t len) |
| { |
| int ret; |
| bool requested_state, current_state; |
| int previous_mode; |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct iio_buffer *buffer = indio_dev->buffer; |
| |
| mutex_lock(&indio_dev->mlock); |
| previous_mode = indio_dev->currentmode; |
| requested_state = !(buf[0] == '0'); |
| current_state = iio_buffer_enabled(indio_dev); |
| if (current_state == requested_state) { |
| printk(KERN_INFO "iio-buffer, current state requested again\n"); |
| goto done; |
| } |
| if (requested_state) { |
| if (indio_dev->setup_ops->preenable) { |
| ret = indio_dev->setup_ops->preenable(indio_dev); |
| if (ret) { |
| printk(KERN_ERR |
| "Buffer not started:" |
| "buffer preenable failed\n"); |
| goto error_ret; |
| } |
| } |
| if (buffer->access->request_update) { |
| ret = buffer->access->request_update(buffer); |
| if (ret) { |
| printk(KERN_INFO |
| "Buffer not started:" |
| "buffer parameter update failed\n"); |
| goto error_ret; |
| } |
| } |
| /* Definitely possible for devices to support both of these.*/ |
| if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) { |
| if (!indio_dev->trig) { |
| printk(KERN_INFO |
| "Buffer not started: no trigger\n"); |
| ret = -EINVAL; |
| goto error_ret; |
| } |
| indio_dev->currentmode = INDIO_BUFFER_TRIGGERED; |
| } else if (indio_dev->modes & INDIO_BUFFER_HARDWARE) |
| indio_dev->currentmode = INDIO_BUFFER_HARDWARE; |
| else { /* should never be reached */ |
| ret = -EINVAL; |
| goto error_ret; |
| } |
| |
| if (indio_dev->setup_ops->postenable) { |
| ret = indio_dev->setup_ops->postenable(indio_dev); |
| if (ret) { |
| printk(KERN_INFO |
| "Buffer not started:" |
| "postenable failed\n"); |
| indio_dev->currentmode = previous_mode; |
| if (indio_dev->setup_ops->postdisable) |
| indio_dev->setup_ops-> |
| postdisable(indio_dev); |
| goto error_ret; |
| } |
| } |
| } else { |
| if (indio_dev->setup_ops->predisable) { |
| ret = indio_dev->setup_ops->predisable(indio_dev); |
| if (ret) |
| goto error_ret; |
| } |
| indio_dev->currentmode = INDIO_DIRECT_MODE; |
| if (indio_dev->setup_ops->postdisable) { |
| ret = indio_dev->setup_ops->postdisable(indio_dev); |
| if (ret) |
| goto error_ret; |
| } |
| } |
| done: |
| mutex_unlock(&indio_dev->mlock); |
| return len; |
| |
| error_ret: |
| mutex_unlock(&indio_dev->mlock); |
| return ret; |
| } |
| EXPORT_SYMBOL(iio_buffer_store_enable); |
| |
| ssize_t iio_buffer_show_enable(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| return sprintf(buf, "%d\n", iio_buffer_enabled(indio_dev)); |
| } |
| EXPORT_SYMBOL(iio_buffer_show_enable); |
| |
| /* note NULL used as error indicator as it doesn't make sense. */ |
| static const unsigned long *iio_scan_mask_match(const unsigned long *av_masks, |
| unsigned int masklength, |
| const unsigned long *mask) |
| { |
| if (bitmap_empty(mask, masklength)) |
| return NULL; |
| while (*av_masks) { |
| if (bitmap_subset(mask, av_masks, masklength)) |
| return av_masks; |
| av_masks += BITS_TO_LONGS(masklength); |
| } |
| return NULL; |
| } |
| |
| static int iio_compute_scan_bytes(struct iio_dev *indio_dev, const long *mask, |
| bool timestamp) |
| { |
| const struct iio_chan_spec *ch; |
| unsigned bytes = 0; |
| int length, i; |
| |
| /* How much space will the demuxed element take? */ |
| for_each_set_bit(i, mask, |
| indio_dev->masklength) { |
| ch = iio_find_channel_from_si(indio_dev, i); |
| length = ch->scan_type.storagebits / 8; |
| bytes = ALIGN(bytes, length); |
| bytes += length; |
| } |
| if (timestamp) { |
| ch = iio_find_channel_from_si(indio_dev, |
| indio_dev->scan_index_timestamp); |
| length = ch->scan_type.storagebits / 8; |
| bytes = ALIGN(bytes, length); |
| bytes += length; |
| } |
| return bytes; |
| } |
| |
| int iio_sw_buffer_preenable(struct iio_dev *indio_dev) |
| { |
| struct iio_buffer *buffer = indio_dev->buffer; |
| unsigned bytes; |
| dev_dbg(&indio_dev->dev, "%s\n", __func__); |
| |
| /* How much space will the demuxed element take? */ |
| bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask, |
| buffer->scan_timestamp); |
| buffer->access->set_bytes_per_datum(buffer, bytes); |
| |
| /* What scan mask do we actually have ?*/ |
| if (indio_dev->available_scan_masks) |
| indio_dev->active_scan_mask = |
| iio_scan_mask_match(indio_dev->available_scan_masks, |
| indio_dev->masklength, |
| buffer->scan_mask); |
| else |
| indio_dev->active_scan_mask = buffer->scan_mask; |
| iio_update_demux(indio_dev); |
| |
| if (indio_dev->info->update_scan_mode) |
| return indio_dev->info |
| ->update_scan_mode(indio_dev, |
| indio_dev->active_scan_mask); |
| return 0; |
| } |
| EXPORT_SYMBOL(iio_sw_buffer_preenable); |
| |
| /** |
| * iio_scan_mask_set() - set particular bit in the scan mask |
| * @buffer: the buffer whose scan mask we are interested in |
| * @bit: the bit to be set. |
| **/ |
| int iio_scan_mask_set(struct iio_dev *indio_dev, |
| struct iio_buffer *buffer, int bit) |
| { |
| const unsigned long *mask; |
| unsigned long *trialmask; |
| |
| trialmask = kmalloc(sizeof(*trialmask)* |
| BITS_TO_LONGS(indio_dev->masklength), |
| GFP_KERNEL); |
| |
| if (trialmask == NULL) |
| return -ENOMEM; |
| if (!indio_dev->masklength) { |
| WARN_ON("trying to set scanmask prior to registering buffer\n"); |
| kfree(trialmask); |
| return -EINVAL; |
| } |
| bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength); |
| set_bit(bit, trialmask); |
| |
| if (indio_dev->available_scan_masks) { |
| mask = iio_scan_mask_match(indio_dev->available_scan_masks, |
| indio_dev->masklength, |
| trialmask); |
| if (!mask) { |
| kfree(trialmask); |
| return -EINVAL; |
| } |
| } |
| bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength); |
| |
| kfree(trialmask); |
| |
| return 0; |
| }; |
| EXPORT_SYMBOL_GPL(iio_scan_mask_set); |
| |
| int iio_scan_mask_query(struct iio_dev *indio_dev, |
| struct iio_buffer *buffer, int bit) |
| { |
| if (bit > indio_dev->masklength) |
| return -EINVAL; |
| |
| if (!buffer->scan_mask) |
| return 0; |
| |
| return test_bit(bit, buffer->scan_mask); |
| }; |
| EXPORT_SYMBOL_GPL(iio_scan_mask_query); |
| |
| /** |
| * struct iio_demux_table() - table describing demux memcpy ops |
| * @from: index to copy from |
| * @to: index to copy to |
| * @length: how many bytes to copy |
| * @l: list head used for management |
| */ |
| struct iio_demux_table { |
| unsigned from; |
| unsigned to; |
| unsigned length; |
| struct list_head l; |
| }; |
| |
| static unsigned char *iio_demux(struct iio_buffer *buffer, |
| unsigned char *datain) |
| { |
| struct iio_demux_table *t; |
| |
| if (list_empty(&buffer->demux_list)) |
| return datain; |
| list_for_each_entry(t, &buffer->demux_list, l) |
| memcpy(buffer->demux_bounce + t->to, |
| datain + t->from, t->length); |
| |
| return buffer->demux_bounce; |
| } |
| |
| int iio_push_to_buffer(struct iio_buffer *buffer, unsigned char *data, |
| s64 timestamp) |
| { |
| unsigned char *dataout = iio_demux(buffer, data); |
| |
| return buffer->access->store_to(buffer, dataout, timestamp); |
| } |
| EXPORT_SYMBOL_GPL(iio_push_to_buffer); |
| |
| int iio_update_demux(struct iio_dev *indio_dev) |
| { |
| const struct iio_chan_spec *ch; |
| struct iio_buffer *buffer = indio_dev->buffer; |
| int ret, in_ind = -1, out_ind, length; |
| unsigned in_loc = 0, out_loc = 0; |
| struct iio_demux_table *p, *q; |
| |
| /* Clear out any old demux */ |
| list_for_each_entry_safe(p, q, &buffer->demux_list, l) { |
| list_del(&p->l); |
| kfree(p); |
| } |
| kfree(buffer->demux_bounce); |
| buffer->demux_bounce = NULL; |
| |
| /* First work out which scan mode we will actually have */ |
| if (bitmap_equal(indio_dev->active_scan_mask, |
| buffer->scan_mask, |
| indio_dev->masklength)) |
| return 0; |
| |
| /* Now we have the two masks, work from least sig and build up sizes */ |
| for_each_set_bit(out_ind, |
| indio_dev->active_scan_mask, |
| indio_dev->masklength) { |
| in_ind = find_next_bit(indio_dev->active_scan_mask, |
| indio_dev->masklength, |
| in_ind + 1); |
| while (in_ind != out_ind) { |
| in_ind = find_next_bit(indio_dev->active_scan_mask, |
| indio_dev->masklength, |
| in_ind + 1); |
| ch = iio_find_channel_from_si(indio_dev, in_ind); |
| length = ch->scan_type.storagebits/8; |
| /* Make sure we are aligned */ |
| in_loc += length; |
| if (in_loc % length) |
| in_loc += length - in_loc % length; |
| } |
| p = kmalloc(sizeof(*p), GFP_KERNEL); |
| if (p == NULL) { |
| ret = -ENOMEM; |
| goto error_clear_mux_table; |
| } |
| ch = iio_find_channel_from_si(indio_dev, in_ind); |
| length = ch->scan_type.storagebits/8; |
| if (out_loc % length) |
| out_loc += length - out_loc % length; |
| if (in_loc % length) |
| in_loc += length - in_loc % length; |
| p->from = in_loc; |
| p->to = out_loc; |
| p->length = length; |
| list_add_tail(&p->l, &buffer->demux_list); |
| out_loc += length; |
| in_loc += length; |
| } |
| /* Relies on scan_timestamp being last */ |
| if (buffer->scan_timestamp) { |
| p = kmalloc(sizeof(*p), GFP_KERNEL); |
| if (p == NULL) { |
| ret = -ENOMEM; |
| goto error_clear_mux_table; |
| } |
| ch = iio_find_channel_from_si(indio_dev, |
| indio_dev->scan_index_timestamp); |
| length = ch->scan_type.storagebits/8; |
| if (out_loc % length) |
| out_loc += length - out_loc % length; |
| if (in_loc % length) |
| in_loc += length - in_loc % length; |
| p->from = in_loc; |
| p->to = out_loc; |
| p->length = length; |
| list_add_tail(&p->l, &buffer->demux_list); |
| out_loc += length; |
| in_loc += length; |
| } |
| buffer->demux_bounce = kzalloc(out_loc, GFP_KERNEL); |
| if (buffer->demux_bounce == NULL) { |
| ret = -ENOMEM; |
| goto error_clear_mux_table; |
| } |
| return 0; |
| |
| error_clear_mux_table: |
| list_for_each_entry_safe(p, q, &buffer->demux_list, l) { |
| list_del(&p->l); |
| kfree(p); |
| } |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(iio_update_demux); |