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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright 2017 Analog Devices Inc.4 * Author: Lars-Peter Clausen <lars@metafoo.de>5 */6 7#include <linux/err.h>8#include <linux/export.h>9#include <linux/slab.h>10#include <linux/module.h>11 12#include <linux/iio/iio.h>13#include <linux/iio/consumer.h>14#include <linux/iio/hw-consumer.h>15#include <linux/iio/buffer_impl.h>16 17/**18 * struct iio_hw_consumer - IIO hw consumer block19 * @buffers: hardware buffers list head.20 * @channels: IIO provider channels.21 */22struct iio_hw_consumer {23 struct list_head buffers;24 struct iio_channel *channels;25};26 27struct hw_consumer_buffer {28 struct list_head head;29 struct iio_dev *indio_dev;30 struct iio_buffer buffer;31 long scan_mask[];32};33 34static struct hw_consumer_buffer *iio_buffer_to_hw_consumer_buffer(35 struct iio_buffer *buffer)36{37 return container_of(buffer, struct hw_consumer_buffer, buffer);38}39 40static void iio_hw_buf_release(struct iio_buffer *buffer)41{42 struct hw_consumer_buffer *hw_buf =43 iio_buffer_to_hw_consumer_buffer(buffer);44 kfree(hw_buf);45}46 47static const struct iio_buffer_access_funcs iio_hw_buf_access = {48 .release = &iio_hw_buf_release,49 .modes = INDIO_BUFFER_HARDWARE,50};51 52static struct hw_consumer_buffer *iio_hw_consumer_get_buffer(53 struct iio_hw_consumer *hwc, struct iio_dev *indio_dev)54{55 unsigned int mask_longs = BITS_TO_LONGS(iio_get_masklength(indio_dev));56 struct hw_consumer_buffer *buf;57 58 list_for_each_entry(buf, &hwc->buffers, head) {59 if (buf->indio_dev == indio_dev)60 return buf;61 }62 63 buf = kzalloc(struct_size(buf, scan_mask, mask_longs), GFP_KERNEL);64 if (!buf)65 return NULL;66 67 buf->buffer.access = &iio_hw_buf_access;68 buf->indio_dev = indio_dev;69 buf->buffer.scan_mask = buf->scan_mask;70 71 iio_buffer_init(&buf->buffer);72 list_add_tail(&buf->head, &hwc->buffers);73 74 return buf;75}76 77/**78 * iio_hw_consumer_alloc() - Allocate IIO hardware consumer79 * @dev: Pointer to consumer device.80 *81 * Returns a valid iio_hw_consumer on success or a ERR_PTR() on failure.82 */83struct iio_hw_consumer *iio_hw_consumer_alloc(struct device *dev)84{85 struct hw_consumer_buffer *buf;86 struct iio_hw_consumer *hwc;87 struct iio_channel *chan;88 int ret;89 90 hwc = kzalloc(sizeof(*hwc), GFP_KERNEL);91 if (!hwc)92 return ERR_PTR(-ENOMEM);93 94 INIT_LIST_HEAD(&hwc->buffers);95 96 hwc->channels = iio_channel_get_all(dev);97 if (IS_ERR(hwc->channels)) {98 ret = PTR_ERR(hwc->channels);99 goto err_free_hwc;100 }101 102 chan = &hwc->channels[0];103 while (chan->indio_dev) {104 buf = iio_hw_consumer_get_buffer(hwc, chan->indio_dev);105 if (!buf) {106 ret = -ENOMEM;107 goto err_put_buffers;108 }109 set_bit(chan->channel->scan_index, buf->buffer.scan_mask);110 chan++;111 }112 113 return hwc;114 115err_put_buffers:116 list_for_each_entry(buf, &hwc->buffers, head)117 iio_buffer_put(&buf->buffer);118 iio_channel_release_all(hwc->channels);119err_free_hwc:120 kfree(hwc);121 return ERR_PTR(ret);122}123EXPORT_SYMBOL_GPL(iio_hw_consumer_alloc);124 125/**126 * iio_hw_consumer_free() - Free IIO hardware consumer127 * @hwc: hw consumer to free.128 */129void iio_hw_consumer_free(struct iio_hw_consumer *hwc)130{131 struct hw_consumer_buffer *buf, *n;132 133 iio_channel_release_all(hwc->channels);134 list_for_each_entry_safe(buf, n, &hwc->buffers, head)135 iio_buffer_put(&buf->buffer);136 kfree(hwc);137}138EXPORT_SYMBOL_GPL(iio_hw_consumer_free);139 140static void devm_iio_hw_consumer_release(void *iio_hwc)141{142 iio_hw_consumer_free(iio_hwc);143}144 145/**146 * devm_iio_hw_consumer_alloc - Resource-managed iio_hw_consumer_alloc()147 * @dev: Pointer to consumer device.148 *149 * Managed iio_hw_consumer_alloc. iio_hw_consumer allocated with this function150 * is automatically freed on driver detach.151 *152 * returns pointer to allocated iio_hw_consumer on success, NULL on failure.153 */154struct iio_hw_consumer *devm_iio_hw_consumer_alloc(struct device *dev)155{156 struct iio_hw_consumer *iio_hwc;157 int ret;158 159 iio_hwc = iio_hw_consumer_alloc(dev);160 if (IS_ERR(iio_hwc))161 return iio_hwc;162 163 ret = devm_add_action_or_reset(dev, devm_iio_hw_consumer_release,164 iio_hwc);165 if (ret)166 return ERR_PTR(ret);167 168 return iio_hwc;169}170EXPORT_SYMBOL_GPL(devm_iio_hw_consumer_alloc);171 172/**173 * iio_hw_consumer_enable() - Enable IIO hardware consumer174 * @hwc: iio_hw_consumer to enable.175 *176 * Returns 0 on success.177 */178int iio_hw_consumer_enable(struct iio_hw_consumer *hwc)179{180 struct hw_consumer_buffer *buf;181 int ret;182 183 list_for_each_entry(buf, &hwc->buffers, head) {184 ret = iio_update_buffers(buf->indio_dev, &buf->buffer, NULL);185 if (ret)186 goto err_disable_buffers;187 }188 189 return 0;190 191err_disable_buffers:192 list_for_each_entry_continue_reverse(buf, &hwc->buffers, head)193 iio_update_buffers(buf->indio_dev, NULL, &buf->buffer);194 return ret;195}196EXPORT_SYMBOL_GPL(iio_hw_consumer_enable);197 198/**199 * iio_hw_consumer_disable() - Disable IIO hardware consumer200 * @hwc: iio_hw_consumer to disable.201 */202void iio_hw_consumer_disable(struct iio_hw_consumer *hwc)203{204 struct hw_consumer_buffer *buf;205 206 list_for_each_entry(buf, &hwc->buffers, head)207 iio_update_buffers(buf->indio_dev, NULL, &buf->buffer);208}209EXPORT_SYMBOL_GPL(iio_hw_consumer_disable);210 211MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");212MODULE_DESCRIPTION("Hardware consumer buffer the IIO framework");213MODULE_LICENSE("GPL v2");214