| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Jonathan Cameron | 3327 | 53.83% | 34 | 33.01% |
| Lars-Peter Clausen | 2166 | 35.04% | 40 | 38.83% |
| Josselin Costanzi | 232 | 3.75% | 1 | 0.97% |
| Octavian Purdila | 161 | 2.60% | 3 | 2.91% |
| Srinivas Pandruvada | 71 | 1.15% | 1 | 0.97% |
| Matt Fornero | 69 | 1.12% | 1 | 0.97% |
| Brian Norris | 68 | 1.10% | 1 | 0.97% |
| Manuel Stahl | 18 | 0.29% | 1 | 0.97% |
| Hartmut Knaack | 9 | 0.15% | 1 | 0.97% |
| Andy Shevchenko | 8 | 0.13% | 1 | 0.97% |
| Irina Tirdea | 7 | 0.11% | 1 | 0.97% |
| SF Markus Elfring | 6 | 0.10% | 1 | 0.97% |
| Peter Meerwald-Stadler | 5 | 0.08% | 2 | 1.94% |
| Linus Torvalds | 5 | 0.08% | 1 | 0.97% |
| Stefan Windfeldt-Prytz | 4 | 0.06% | 1 | 0.97% |
| Tejun Heo | 3 | 0.05% | 1 | 0.97% |
| Paul Gortmaker | 3 | 0.05% | 1 | 0.97% |
| Dan Carpenter | 3 | 0.05% | 1 | 0.97% |
| Alec Berg | 3 | 0.05% | 1 | 0.97% |
| Thomas Gleixner | 2 | 0.03% | 1 | 0.97% |
| Colin Ian King | 2 | 0.03% | 1 | 0.97% |
| Michał Mirosław | 2 | 0.03% | 1 | 0.97% |
| Cristina Opriceana | 2 | 0.03% | 2 | 1.94% |
| Thomas Meyer | 2 | 0.03% | 1 | 0.97% |
| Al Viro | 1 | 0.02% | 1 | 0.97% |
| Greg Kroah-Hartman | 1 | 0.02% | 1 | 0.97% |
| Ingo Molnar | 1 | 0.02% | 1 | 0.97% |
| Total | 6181 | 103 |
// SPDX-License-Identifier: GPL-2.0-only /* The industrial I/O core * * Copyright (c) 2008 Jonathan Cameron * * 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 <linux/sched/signal.h> #include <linux/iio/iio.h> #include "iio_core.h" #include <linux/iio/sysfs.h> #include <linux/iio/buffer.h> #include <linux/iio/buffer_impl.h> static const char * const iio_endian_prefix[] = { [IIO_BE] = "be", [IIO_LE] = "le", }; static bool iio_buffer_is_active(struct iio_buffer *buf) { return !list_empty(&buf->buffer_list); } static size_t iio_buffer_data_available(struct iio_buffer *buf) { return buf->access->data_available(buf); } static int iio_buffer_flush_hwfifo(struct iio_dev *indio_dev, struct iio_buffer *buf, size_t required) { if (!indio_dev->info->hwfifo_flush_to_buffer) return -ENODEV; return indio_dev->info->hwfifo_flush_to_buffer(indio_dev, required); } static bool iio_buffer_ready(struct iio_dev *indio_dev, struct iio_buffer *buf, size_t to_wait, int to_flush) { size_t avail; int flushed = 0; /* wakeup if the device was unregistered */ if (!indio_dev->info) return true; /* drain the buffer if it was disabled */ if (!iio_buffer_is_active(buf)) { to_wait = min_t(size_t, to_wait, 1); to_flush = 0; } avail = iio_buffer_data_available(buf); if (avail >= to_wait) { /* force a flush for non-blocking reads */ if (!to_wait && avail < to_flush) iio_buffer_flush_hwfifo(indio_dev, buf, to_flush - avail); return true; } if (to_flush) flushed = iio_buffer_flush_hwfifo(indio_dev, buf, to_wait - avail); if (flushed <= 0) return false; if (avail + flushed >= to_wait) return true; return false; } /** * iio_buffer_read_first_n_outer() - chrdev read for buffer access * @filp: File structure pointer for the char device * @buf: Destination buffer for iio buffer read * @n: First n bytes to read * @f_ps: Long offset provided by the user as a seek position * * This function relies on all buffer implementations having an * iio_buffer as their first element. * * Return: negative values corresponding to error codes or ret != 0 * for ending the reading activity **/ 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; DEFINE_WAIT_FUNC(wait, woken_wake_function); size_t datum_size; size_t to_wait; int ret = 0; if (!indio_dev->info) return -ENODEV; if (!rb || !rb->access->read_first_n) return -EINVAL; datum_size = rb->bytes_per_datum; /* * If datum_size is 0 there will never be anything to read from the * buffer, so signal end of file now. */ if (!datum_size) return 0; if (filp->f_flags & O_NONBLOCK) to_wait = 0; else to_wait = min_t(size_t, n / datum_size, rb->watermark); add_wait_queue(&rb->pollq, &wait); do { if (!indio_dev->info) { ret = -ENODEV; break; } if (!iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size)) { if (signal_pending(current)) { ret = -ERESTARTSYS; break; } wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); continue; } ret = rb->access->read_first_n(rb, n, buf); if (ret == 0 && (filp->f_flags & O_NONBLOCK)) ret = -EAGAIN; } while (ret == 0); remove_wait_queue(&rb->pollq, &wait); return ret; } /** * iio_buffer_poll() - poll the buffer to find out if it has data * @filp: File structure pointer for device access * @wait: Poll table structure pointer for which the driver adds * a wait queue * * Return: (EPOLLIN | EPOLLRDNORM) if data is available for reading * or 0 for other cases */ __poll_t 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; if (!indio_dev->info || rb == NULL) return 0; poll_wait(filp, &rb->pollq, wait); if (iio_buffer_ready(indio_dev, rb, rb->watermark, 0)) return EPOLLIN | EPOLLRDNORM; return 0; } /** * iio_buffer_wakeup_poll - Wakes up the buffer waitqueue * @indio_dev: The IIO device * * Wakes up the event waitqueue used for poll(). Should usually * be called when the device is unregistered. */ void iio_buffer_wakeup_poll(struct iio_dev *indio_dev) { if (!indio_dev->buffer) return; wake_up(&indio_dev->buffer->pollq); } void iio_buffer_init(struct iio_buffer *buffer) { INIT_LIST_HEAD(&buffer->demux_list); INIT_LIST_HEAD(&buffer->buffer_list); init_waitqueue_head(&buffer->pollq); kref_init(&buffer->ref); if (!buffer->watermark) buffer->watermark = 1; } EXPORT_SYMBOL(iio_buffer_init); /** * iio_buffer_set_attrs - Set buffer specific attributes * @buffer: The buffer for which we are setting attributes * @attrs: Pointer to a null terminated list of pointers to attributes */ void iio_buffer_set_attrs(struct iio_buffer *buffer, const struct attribute **attrs) { buffer->attrs = attrs; } EXPORT_SYMBOL_GPL(iio_buffer_set_attrs); 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 } if (this_attr->c->scan_type.repeat > 1) return sprintf(buf, "%s:%c%d/%dX%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.repeat, this_attr->c->scan_type.shift); else 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_to_iio_dev(dev); /* Ensure ret is 0 or 1. */ ret = !!test_bit(to_iio_dev_attr(attr)->address, indio_dev->buffer->scan_mask); return sprintf(buf, "%d\n", ret); } /* 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, bool strict) { if (bitmap_empty(mask, masklength)) return NULL; while (*av_masks) { if (strict) { if (bitmap_equal(mask, av_masks, masklength)) return av_masks; } else { if (bitmap_subset(mask, av_masks, masklength)) return av_masks; } av_masks += BITS_TO_LONGS(masklength); } return NULL; } static bool iio_validate_scan_mask(struct iio_dev *indio_dev, const unsigned long *mask) { if (!indio_dev->setup_ops->validate_scan_mask) return true; return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask); } /** * iio_scan_mask_set() - set particular bit in the scan mask * @indio_dev: the iio device * @buffer: the buffer whose scan mask we are interested in * @bit: the bit to be set. * * Note that at this point we have no way of knowing what other * buffers might request, hence this code only verifies that the * individual buffers request is plausible. */ static int iio_scan_mask_set(struct iio_dev *indio_dev, struct iio_buffer *buffer, int bit) { const unsigned long *mask; unsigned long *trialmask; trialmask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), sizeof(*trialmask), GFP_KERNEL); if (trialmask == NULL) return -ENOMEM; if (!indio_dev->masklength) { WARN(1, "Trying to set scanmask prior to registering buffer\n"); goto err_invalid_mask; } bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength); set_bit(bit, trialmask); if (!iio_validate_scan_mask(indio_dev, trialmask)) goto err_invalid_mask; if (indio_dev->available_scan_masks) { mask = iio_scan_mask_match(indio_dev->available_scan_masks, indio_dev->masklength, trialmask, false); if (!mask) goto err_invalid_mask; } bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength); bitmap_free(trialmask); return 0; err_invalid_mask: bitmap_free(trialmask); return -EINVAL; } static int iio_scan_mask_clear(struct iio_buffer *buffer, int bit) { clear_bit(bit, buffer->scan_mask); return 0; } static 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; /* Ensure return value is 0 or 1. */ return !!test_bit(bit, buffer->scan_mask); }; 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_to_iio_dev(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_is_active(indio_dev->buffer)) { 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_to_iio_dev(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_to_iio_dev(dev); bool state; ret = strtobool(buf, &state); if (ret < 0) return ret; mutex_lock(&indio_dev->mlock); if (iio_buffer_is_active(indio_dev->buffer)) { 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, IIO_SEPARATE, &indio_dev->dev, &buffer->scan_el_dev_attr_list); if (ret) return 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) return 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); if (ret) return ret; attrcount++; ret = attrcount; return ret; } static ssize_t iio_buffer_read_length(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct iio_buffer *buffer = indio_dev->buffer; return sprintf(buf, "%d\n", buffer->length); } static ssize_t iio_buffer_write_length(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_buffer *buffer = indio_dev->buffer; unsigned int val; int ret; ret = kstrtouint(buf, 10, &val); if (ret) return ret; if (val == buffer->length) return len; mutex_lock(&indio_dev->mlock); if (iio_buffer_is_active(indio_dev->buffer)) { ret = -EBUSY; } else { buffer->access->set_length(buffer, val); ret = 0; } if (ret) goto out; if (buffer->length && buffer->length < buffer->watermark) buffer->watermark = buffer->length; out: mutex_unlock(&indio_dev->mlock); return ret ? ret : len; } static ssize_t iio_buffer_show_enable(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); return sprintf(buf, "%d\n", iio_buffer_is_active(indio_dev->buffer)); } static unsigned int iio_storage_bytes_for_si(struct iio_dev *indio_dev, unsigned int scan_index) { const struct iio_chan_spec *ch; unsigned int bytes; ch = iio_find_channel_from_si(indio_dev, scan_index); bytes = ch->scan_type.storagebits / 8; if (ch->scan_type.repeat > 1) bytes *= ch->scan_type.repeat; return bytes; } static unsigned int iio_storage_bytes_for_timestamp(struct iio_dev *indio_dev) { return iio_storage_bytes_for_si(indio_dev, indio_dev->scan_index_timestamp); } static int iio_compute_scan_bytes(struct iio_dev *indio_dev, const unsigned long *mask, bool timestamp) { unsigned bytes = 0; int length, i; /* How much space will the demuxed element take? */ for_each_set_bit(i, mask, indio_dev->masklength) { length = iio_storage_bytes_for_si(indio_dev, i); bytes = ALIGN(bytes, length); bytes += length; } if (timestamp) { length = iio_storage_bytes_for_timestamp(indio_dev); bytes = ALIGN(bytes, length); bytes += length; } return bytes; } static void iio_buffer_activate(struct iio_dev *indio_dev, struct iio_buffer *buffer) { iio_buffer_get(buffer); list_add(&buffer->buffer_list, &indio_dev->buffer_list); } static void iio_buffer_deactivate(struct iio_buffer *buffer) { list_del_init(&buffer->buffer_list); wake_up_interruptible(&buffer->pollq); iio_buffer_put(buffer); } static void iio_buffer_deactivate_all(struct iio_dev *indio_dev) { struct iio_buffer *buffer, *_buffer; list_for_each_entry_safe(buffer, _buffer, &indio_dev->buffer_list, buffer_list) iio_buffer_deactivate(buffer); } static int iio_buffer_enable(struct iio_buffer *buffer, struct iio_dev *indio_dev) { if (!buffer->access->enable) return 0; return buffer->access->enable(buffer, indio_dev); } static int iio_buffer_disable(struct iio_buffer *buffer, struct iio_dev *indio_dev) { if (!buffer->access->disable) return 0; return buffer->access->disable(buffer, indio_dev); } static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev, struct iio_buffer *buffer) { unsigned int bytes; if (!buffer->access->set_bytes_per_datum) return; bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask, buffer->scan_timestamp); buffer->access->set_bytes_per_datum(buffer, bytes); } static int iio_buffer_request_update(struct iio_dev *indio_dev, struct iio_buffer *buffer) { int ret; iio_buffer_update_bytes_per_datum(indio_dev, buffer); if (buffer->access->request_update) { ret = buffer->access->request_update(buffer); if (ret) { dev_dbg(&indio_dev->dev, "Buffer not started: buffer parameter update failed (%d)\n", ret); return ret; } } return 0; } static void iio_free_scan_mask(struct iio_dev *indio_dev, const unsigned long *mask) { /* If the mask is dynamically allocated free it, otherwise do nothing */ if (!indio_dev->available_scan_masks) bitmap_free(mask); } struct iio_device_config { unsigned int mode; unsigned int watermark; const unsigned long *scan_mask; unsigned int scan_bytes; bool scan_timestamp; }; static int iio_verify_update(struct iio_dev *indio_dev, struct iio_buffer *insert_buffer, struct iio_buffer *remove_buffer, struct iio_device_config *config) { unsigned long *compound_mask; const unsigned long *scan_mask; bool strict_scanmask = false; struct iio_buffer *buffer; bool scan_timestamp; unsigned int modes; memset(config, 0, sizeof(*config)); config->watermark = ~0; /* * If there is just one buffer and we are removing it there is nothing * to verify. */ if (remove_buffer && !insert_buffer && list_is_singular(&indio_dev->buffer_list)) return 0; modes = indio_dev->modes; list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { if (buffer == remove_buffer) continue; modes &= buffer->access->modes; config->watermark = min(config->watermark, buffer->watermark); } if (insert_buffer) { modes &= insert_buffer->access->modes; config->watermark = min(config->watermark, insert_buffer->watermark); } /* Definitely possible for devices to support both of these. */ if ((modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) { config->mode = INDIO_BUFFER_TRIGGERED; } else if (modes & INDIO_BUFFER_HARDWARE) { /* * Keep things simple for now and only allow a single buffer to * be connected in hardware mode. */ if (insert_buffer && !list_empty(&indio_dev->buffer_list)) return -EINVAL; config->mode = INDIO_BUFFER_HARDWARE; strict_scanmask = true; } else if (modes & INDIO_BUFFER_SOFTWARE) { config->mode = INDIO_BUFFER_SOFTWARE; } else { /* Can only occur on first buffer */ if (indio_dev->modes & INDIO_BUFFER_TRIGGERED) dev_dbg(&indio_dev->dev, "Buffer not started: no trigger\n"); return -EINVAL; } /* What scan mask do we actually have? */ compound_mask = bitmap_zalloc(indio_dev->masklength, GFP_KERNEL); if (compound_mask == NULL) return -ENOMEM; scan_timestamp = false; list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { if (buffer == remove_buffer) continue; bitmap_or(compound_mask, compound_mask, buffer->scan_mask, indio_dev->masklength); scan_timestamp |= buffer->scan_timestamp; } if (insert_buffer) { bitmap_or(compound_mask, compound_mask, insert_buffer->scan_mask, indio_dev->masklength); scan_timestamp |= insert_buffer->scan_timestamp; } if (indio_dev->available_scan_masks) { scan_mask = iio_scan_mask_match(indio_dev->available_scan_masks, indio_dev->masklength, compound_mask, strict_scanmask); bitmap_free(compound_mask); if (scan_mask == NULL) return -EINVAL; } else { scan_mask = compound_mask; } config->scan_bytes = iio_compute_scan_bytes(indio_dev, scan_mask, scan_timestamp); config->scan_mask = scan_mask; config->scan_timestamp = scan_timestamp; return 0; } /** * 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 void iio_buffer_demux_free(struct iio_buffer *buffer) { struct iio_demux_table *p, *q; list_for_each_entry_safe(p, q, &buffer->demux_list, l) { list_del(&p->l); kfree(p); } } static int iio_buffer_add_demux(struct iio_buffer *buffer, struct iio_demux_table **p, unsigned int in_loc, unsigned int out_loc, unsigned int length) { if (*p && (*p)->from + (*p)->length == in_loc && (*p)->to + (*p)->length == out_loc) { (*p)->length += length; } else { *p = kmalloc(sizeof(**p), GFP_KERNEL); if (*p == NULL) return -ENOMEM; (*p)->from = in_loc; (*p)->to = out_loc; (*p)->length = length; list_add_tail(&(*p)->l, &buffer->demux_list); } return 0; } static int iio_buffer_update_demux(struct iio_dev *indio_dev, struct iio_buffer *buffer) { int ret, in_ind = -1, out_ind, length; unsigned in_loc = 0, out_loc = 0; struct iio_demux_table *p = NULL; /* Clear out any old demux */ iio_buffer_demux_free(buffer); 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, buffer->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); length = iio_storage_bytes_for_si(indio_dev, in_ind); /* Make sure we are aligned */ in_loc = roundup(in_loc, length) + length; } length = iio_storage_bytes_for_si(indio_dev, in_ind); out_loc = roundup(out_loc, length); in_loc = roundup(in_loc, length); ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); if (ret) goto error_clear_mux_table; out_loc += length; in_loc += length; } /* Relies on scan_timestamp being last */ if (buffer->scan_timestamp) { length = iio_storage_bytes_for_timestamp(indio_dev); out_loc = roundup(out_loc, length); in_loc = roundup(in_loc, length); ret = iio_buffer_add_demux(buffer, &p, in_loc, out_loc, length); if (ret) goto error_clear_mux_table; 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: iio_buffer_demux_free(buffer); return ret; } static int iio_update_demux(struct iio_dev *indio_dev) { struct iio_buffer *buffer; int ret; list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { ret = iio_buffer_update_demux(indio_dev, buffer); if (ret < 0) goto error_clear_mux_table; } return 0; error_clear_mux_table: list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) iio_buffer_demux_free(buffer); return ret; } static int iio_enable_buffers(struct iio_dev *indio_dev, struct iio_device_config *config) { struct iio_buffer *buffer; int ret; indio_dev->active_scan_mask = config->scan_mask; indio_dev->scan_timestamp = config->scan_timestamp; indio_dev->scan_bytes = config->scan_bytes; iio_update_demux(indio_dev); /* Wind up again */ if (indio_dev->setup_ops->preenable) { ret = indio_dev->setup_ops->preenable(indio_dev); if (ret) { dev_dbg(&indio_dev->dev, "Buffer not started: buffer preenable failed (%d)\n", ret); goto err_undo_config; } } if (indio_dev->info->update_scan_mode) { ret = indio_dev->info ->update_scan_mode(indio_dev, indio_dev->active_scan_mask); if (ret < 0) { dev_dbg(&indio_dev->dev, "Buffer not started: update scan mode failed (%d)\n", ret); goto err_run_postdisable; } } if (indio_dev->info->hwfifo_set_watermark) indio_dev->info->hwfifo_set_watermark(indio_dev, config->watermark); list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { ret = iio_buffer_enable(buffer, indio_dev); if (ret) goto err_disable_buffers; } indio_dev->currentmode = config->mode; if (indio_dev->setup_ops->postenable) { ret = indio_dev->setup_ops->postenable(indio_dev); if (ret) { dev_dbg(&indio_dev->dev, "Buffer not started: postenable failed (%d)\n", ret); goto err_disable_buffers; } } return 0; err_disable_buffers: list_for_each_entry_continue_reverse(buffer, &indio_dev->buffer_list, buffer_list) iio_buffer_disable(buffer, indio_dev); err_run_postdisable: indio_dev->currentmode = INDIO_DIRECT_MODE; if (indio_dev->setup_ops->postdisable) indio_dev->setup_ops->postdisable(indio_dev); err_undo_config: indio_dev->active_scan_mask = NULL; return ret; } static int iio_disable_buffers(struct iio_dev *indio_dev) { struct iio_buffer *buffer; int ret = 0; int ret2; /* Wind down existing buffers - iff there are any */ if (list_empty(&indio_dev->buffer_list)) return 0; /* * If things go wrong at some step in disable we still need to continue * to perform the other steps, otherwise we leave the device in a * inconsistent state. We return the error code for the first error we * encountered. */ if (indio_dev->setup_ops->predisable) { ret2 = indio_dev->setup_ops->predisable(indio_dev); if (ret2 && !ret) ret = ret2; } list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) { ret2 = iio_buffer_disable(buffer, indio_dev); if (ret2 && !ret) ret = ret2; } indio_dev->currentmode = INDIO_DIRECT_MODE; if (indio_dev->setup_ops->postdisable) { ret2 = indio_dev->setup_ops->postdisable(indio_dev); if (ret2 && !ret) ret = ret2; } iio_free_scan_mask(indio_dev, indio_dev->active_scan_mask); indio_dev->active_scan_mask = NULL; return ret; } static int __iio_update_buffers(struct iio_dev *indio_dev, struct iio_buffer *insert_buffer, struct iio_buffer *remove_buffer) { struct iio_device_config new_config; int ret; ret = iio_verify_update(indio_dev, insert_buffer, remove_buffer, &new_config); if (ret) return ret; if (insert_buffer) { ret = iio_buffer_request_update(indio_dev, insert_buffer); if (ret) goto err_free_config; } ret = iio_disable_buffers(indio_dev); if (ret) goto err_deactivate_all; if (remove_buffer) iio_buffer_deactivate(remove_buffer); if (insert_buffer) iio_buffer_activate(indio_dev, insert_buffer); /* If no buffers in list, we are done */ if (list_empty(&indio_dev->buffer_list)) return 0; ret = iio_enable_buffers(indio_dev, &new_config); if (ret) goto err_deactivate_all; return 0; err_deactivate_all: /* * We've already verified that the config is valid earlier. If things go * wrong in either enable or disable the most likely reason is an IO * error from the device. In this case there is no good recovery * strategy. Just make sure to disable everything and leave the device * in a sane state. With a bit of luck the device might come back to * life again later and userspace can try again. */ iio_buffer_deactivate_all(indio_dev); err_free_config: iio_free_scan_mask(indio_dev, new_config.scan_mask); return ret; } int iio_update_buffers(struct iio_dev *indio_dev, struct iio_buffer *insert_buffer, struct iio_buffer *remove_buffer) { int ret; if (insert_buffer == remove_buffer) return 0; mutex_lock(&indio_dev->info_exist_lock); mutex_lock(&indio_dev->mlock); if (insert_buffer && iio_buffer_is_active(insert_buffer)) insert_buffer = NULL; if (remove_buffer && !iio_buffer_is_active(remove_buffer)) remove_buffer = NULL; if (!insert_buffer && !remove_buffer) { ret = 0; goto out_unlock; } if (indio_dev->info == NULL) { ret = -ENODEV; goto out_unlock; } ret = __iio_update_buffers(indio_dev, insert_buffer, remove_buffer); out_unlock: mutex_unlock(&indio_dev->mlock); mutex_unlock(&indio_dev->info_exist_lock); return ret; } EXPORT_SYMBOL_GPL(iio_update_buffers); void iio_disable_all_buffers(struct iio_dev *indio_dev) { iio_disable_buffers(indio_dev); iio_buffer_deactivate_all(indio_dev); } static ssize_t iio_buffer_store_enable(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { int ret; bool requested_state; struct iio_dev *indio_dev = dev_to_iio_dev(dev); bool inlist; ret = strtobool(buf, &requested_state); if (ret < 0) return ret; mutex_lock(&indio_dev->mlock); /* Find out if it is in the list */ inlist = iio_buffer_is_active(indio_dev->buffer); /* Already in desired state */ if (inlist == requested_state) goto done; if (requested_state) ret = __iio_update_buffers(indio_dev, indio_dev->buffer, NULL); else ret = __iio_update_buffers(indio_dev, NULL, indio_dev->buffer); done: mutex_unlock(&indio_dev->mlock); return (ret < 0) ? ret : len; } static const char * const iio_scan_elements_group_name = "scan_elements"; static ssize_t iio_buffer_show_watermark(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); struct iio_buffer *buffer = indio_dev->buffer; return sprintf(buf, "%u\n", buffer->watermark); } static ssize_t iio_buffer_store_watermark(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_buffer *buffer = indio_dev->buffer; unsigned int val; int ret; ret = kstrtouint(buf, 10, &val); if (ret) return ret; if (!val) return -EINVAL; mutex_lock(&indio_dev->mlock); if (val > buffer->length) { ret = -EINVAL; goto out; } if (iio_buffer_is_active(indio_dev->buffer)) { ret = -EBUSY; goto out; } buffer->watermark = val; out: mutex_unlock(&indio_dev->mlock); return ret ? ret : len; } static ssize_t iio_dma_show_data_available(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_to_iio_dev(dev); size_t bytes; bytes = iio_buffer_data_available(indio_dev->buffer); return sprintf(buf, "%zu\n", bytes); } static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length, iio_buffer_write_length); static struct device_attribute dev_attr_length_ro = __ATTR(length, S_IRUGO, iio_buffer_read_length, NULL); static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, iio_buffer_show_enable, iio_buffer_store_enable); static DEVICE_ATTR(watermark, S_IRUGO | S_IWUSR, iio_buffer_show_watermark, iio_buffer_store_watermark); static struct device_attribute dev_attr_watermark_ro = __ATTR(watermark, S_IRUGO, iio_buffer_show_watermark, NULL); static DEVICE_ATTR(data_available, S_IRUGO, iio_dma_show_data_available, NULL); static struct attribute *iio_buffer_attrs[] = { &dev_attr_length.attr, &dev_attr_enable.attr, &dev_attr_watermark.attr, &dev_attr_data_available.attr, }; int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev) { struct iio_dev_attr *p; struct attribute **attr; struct iio_buffer *buffer = indio_dev->buffer; int ret, i, attrn, attrcount, attrcount_orig = 0; const struct iio_chan_spec *channels; channels = indio_dev->channels; if (channels) { int ml = indio_dev->masklength; for (i = 0; i < indio_dev->num_channels; i++) ml = max(ml, channels[i].scan_index + 1); indio_dev->masklength = ml; } if (!buffer) return 0; attrcount = 0; if (buffer->attrs) { while (buffer->attrs[attrcount] != NULL) attrcount++; } attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, sizeof(struct attribute *), GFP_KERNEL); if (!attr) return -ENOMEM; memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); if (!buffer->access->set_length) attr[0] = &dev_attr_length_ro.attr; if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) attr[2] = &dev_attr_watermark_ro.attr; if (buffer->attrs) memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, sizeof(struct attribute *) * attrcount); attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; buffer->buffer_group.name = "buffer"; buffer->buffer_group.attrs = attr; indio_dev->groups[indio_dev->groupcounter++] = &buffer->buffer_group; 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); channels = indio_dev->channels; if (channels) { /* new magic */ for (i = 0; i < indio_dev->num_channels; i++) { if (channels[i].scan_index < 0) continue; 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 = bitmap_zalloc(indio_dev->masklength, 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: bitmap_free(buffer->scan_mask); error_cleanup_dynamic: iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); kfree(indio_dev->buffer->buffer_group.attrs); return ret; } void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev) { if (!indio_dev->buffer) return; bitmap_free(indio_dev->buffer->scan_mask); kfree(indio_dev->buffer->buffer_group.attrs); kfree(indio_dev->buffer->scan_el_group.attrs); iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list); } /** * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected * @indio_dev: the iio device * @mask: scan mask to be checked * * Return true if exactly one bit is set in the scan mask, false otherwise. It * can be used for devices where only one channel can be active for sampling at * a time. */ bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, const unsigned long *mask) { return bitmap_weight(mask, indio_dev->masklength) == 1; } EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot); static const void *iio_demux(struct iio_buffer *buffer, const void *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; } static int iio_push_to_buffer(struct iio_buffer *buffer, const void *data) { const void *dataout = iio_demux(buffer, data); int ret; ret = buffer->access->store_to(buffer, dataout); if (ret) return ret; /* * We can't just test for watermark to decide if we wake the poll queue * because read may request less samples than the watermark. */ wake_up_interruptible_poll(&buffer->pollq, EPOLLIN | EPOLLRDNORM); return 0; } /** * iio_push_to_buffers() - push to a registered buffer. * @indio_dev: iio_dev structure for device. * @data: Full scan. */ int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data) { int ret; struct iio_buffer *buf; list_for_each_entry(buf, &indio_dev->buffer_list, buffer_list) { ret = iio_push_to_buffer(buf, data); if (ret < 0) return ret; } return 0; } EXPORT_SYMBOL_GPL(iio_push_to_buffers); /** * iio_buffer_release() - Free a buffer's resources * @ref: Pointer to the kref embedded in the iio_buffer struct * * This function is called when the last reference to the buffer has been * dropped. It will typically free all resources allocated by the buffer. Do not * call this function manually, always use iio_buffer_put() when done using a * buffer. */ static void iio_buffer_release(struct kref *ref) { struct iio_buffer *buffer = container_of(ref, struct iio_buffer, ref); buffer->access->release(buffer); } /** * iio_buffer_get() - Grab a reference to the buffer * @buffer: The buffer to grab a reference for, may be NULL * * Returns the pointer to the buffer that was passed into the function. */ struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer) { if (buffer) kref_get(&buffer->ref); return buffer; } EXPORT_SYMBOL_GPL(iio_buffer_get); /** * iio_buffer_put() - Release the reference to the buffer * @buffer: The buffer to release the reference for, may be NULL */ void iio_buffer_put(struct iio_buffer *buffer) { if (buffer) kref_put(&buffer->ref, iio_buffer_release); } EXPORT_SYMBOL_GPL(iio_buffer_put); /** * iio_device_attach_buffer - Attach a buffer to a IIO device * @indio_dev: The device the buffer should be attached to * @buffer: The buffer to attach to the device * * This function attaches a buffer to a IIO device. The buffer stays attached to * the device until the device is freed. The function should only be called at * most once per device. */ void iio_device_attach_buffer(struct iio_dev *indio_dev, struct iio_buffer *buffer) { indio_dev->buffer = iio_buffer_get(buffer); } EXPORT_SYMBOL_GPL(iio_device_attach_buffer);
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