diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/iio/buffer/industrialio-hw-consumer.c | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/drivers/iio/buffer/industrialio-hw-consumer.c b/drivers/iio/buffer/industrialio-hw-consumer.c new file mode 100644 index 000000000..95165697d --- /dev/null +++ b/drivers/iio/buffer/industrialio-hw-consumer.c @@ -0,0 +1,247 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2017 Analog Devices Inc. + * Author: Lars-Peter Clausen <lars@metafoo.de> + */ + +#include <linux/err.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/module.h> + +#include <linux/iio/iio.h> +#include <linux/iio/consumer.h> +#include <linux/iio/hw-consumer.h> +#include <linux/iio/buffer_impl.h> + +/** + * struct iio_hw_consumer - IIO hw consumer block + * @buffers: hardware buffers list head. + * @channels: IIO provider channels. + */ +struct iio_hw_consumer { + struct list_head buffers; + struct iio_channel *channels; +}; + +struct hw_consumer_buffer { + struct list_head head; + struct iio_dev *indio_dev; + struct iio_buffer buffer; + long scan_mask[]; +}; + +static struct hw_consumer_buffer *iio_buffer_to_hw_consumer_buffer( + struct iio_buffer *buffer) +{ + return container_of(buffer, struct hw_consumer_buffer, buffer); +} + +static void iio_hw_buf_release(struct iio_buffer *buffer) +{ + struct hw_consumer_buffer *hw_buf = + iio_buffer_to_hw_consumer_buffer(buffer); + kfree(hw_buf); +} + +static const struct iio_buffer_access_funcs iio_hw_buf_access = { + .release = &iio_hw_buf_release, + .modes = INDIO_BUFFER_HARDWARE, +}; + +static struct hw_consumer_buffer *iio_hw_consumer_get_buffer( + struct iio_hw_consumer *hwc, struct iio_dev *indio_dev) +{ + size_t mask_size = BITS_TO_LONGS(indio_dev->masklength) * sizeof(long); + struct hw_consumer_buffer *buf; + + list_for_each_entry(buf, &hwc->buffers, head) { + if (buf->indio_dev == indio_dev) + return buf; + } + + buf = kzalloc(sizeof(*buf) + mask_size, GFP_KERNEL); + if (!buf) + return NULL; + + buf->buffer.access = &iio_hw_buf_access; + buf->indio_dev = indio_dev; + buf->buffer.scan_mask = buf->scan_mask; + + iio_buffer_init(&buf->buffer); + list_add_tail(&buf->head, &hwc->buffers); + + return buf; +} + +/** + * iio_hw_consumer_alloc() - Allocate IIO hardware consumer + * @dev: Pointer to consumer device. + * + * Returns a valid iio_hw_consumer on success or a ERR_PTR() on failure. + */ +struct iio_hw_consumer *iio_hw_consumer_alloc(struct device *dev) +{ + struct hw_consumer_buffer *buf; + struct iio_hw_consumer *hwc; + struct iio_channel *chan; + int ret; + + hwc = kzalloc(sizeof(*hwc), GFP_KERNEL); + if (!hwc) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&hwc->buffers); + + hwc->channels = iio_channel_get_all(dev); + if (IS_ERR(hwc->channels)) { + ret = PTR_ERR(hwc->channels); + goto err_free_hwc; + } + + chan = &hwc->channels[0]; + while (chan->indio_dev) { + buf = iio_hw_consumer_get_buffer(hwc, chan->indio_dev); + if (!buf) { + ret = -ENOMEM; + goto err_put_buffers; + } + set_bit(chan->channel->scan_index, buf->buffer.scan_mask); + chan++; + } + + return hwc; + +err_put_buffers: + list_for_each_entry(buf, &hwc->buffers, head) + iio_buffer_put(&buf->buffer); + iio_channel_release_all(hwc->channels); +err_free_hwc: + kfree(hwc); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(iio_hw_consumer_alloc); + +/** + * iio_hw_consumer_free() - Free IIO hardware consumer + * @hwc: hw consumer to free. + */ +void iio_hw_consumer_free(struct iio_hw_consumer *hwc) +{ + struct hw_consumer_buffer *buf, *n; + + iio_channel_release_all(hwc->channels); + list_for_each_entry_safe(buf, n, &hwc->buffers, head) + iio_buffer_put(&buf->buffer); + kfree(hwc); +} +EXPORT_SYMBOL_GPL(iio_hw_consumer_free); + +static void devm_iio_hw_consumer_release(struct device *dev, void *res) +{ + iio_hw_consumer_free(*(struct iio_hw_consumer **)res); +} + +static int devm_iio_hw_consumer_match(struct device *dev, void *res, void *data) +{ + struct iio_hw_consumer **r = res; + + if (!r || !*r) { + WARN_ON(!r || !*r); + return 0; + } + return *r == data; +} + +/** + * devm_iio_hw_consumer_alloc - Resource-managed iio_hw_consumer_alloc() + * @dev: Pointer to consumer device. + * + * Managed iio_hw_consumer_alloc. iio_hw_consumer allocated with this function + * is automatically freed on driver detach. + * + * If an iio_hw_consumer allocated with this function needs to be freed + * separately, devm_iio_hw_consumer_free() must be used. + * + * returns pointer to allocated iio_hw_consumer on success, NULL on failure. + */ +struct iio_hw_consumer *devm_iio_hw_consumer_alloc(struct device *dev) +{ + struct iio_hw_consumer **ptr, *iio_hwc; + + ptr = devres_alloc(devm_iio_hw_consumer_release, sizeof(*ptr), + GFP_KERNEL); + if (!ptr) + return NULL; + + iio_hwc = iio_hw_consumer_alloc(dev); + if (IS_ERR(iio_hwc)) { + devres_free(ptr); + } else { + *ptr = iio_hwc; + devres_add(dev, ptr); + } + + return iio_hwc; +} +EXPORT_SYMBOL_GPL(devm_iio_hw_consumer_alloc); + +/** + * devm_iio_hw_consumer_free - Resource-managed iio_hw_consumer_free() + * @dev: Pointer to consumer device. + * @hwc: iio_hw_consumer to free. + * + * Free iio_hw_consumer allocated with devm_iio_hw_consumer_alloc(). + */ +void devm_iio_hw_consumer_free(struct device *dev, struct iio_hw_consumer *hwc) +{ + int rc; + + rc = devres_release(dev, devm_iio_hw_consumer_release, + devm_iio_hw_consumer_match, hwc); + WARN_ON(rc); +} +EXPORT_SYMBOL_GPL(devm_iio_hw_consumer_free); + +/** + * iio_hw_consumer_enable() - Enable IIO hardware consumer + * @hwc: iio_hw_consumer to enable. + * + * Returns 0 on success. + */ +int iio_hw_consumer_enable(struct iio_hw_consumer *hwc) +{ + struct hw_consumer_buffer *buf; + int ret; + + list_for_each_entry(buf, &hwc->buffers, head) { + ret = iio_update_buffers(buf->indio_dev, &buf->buffer, NULL); + if (ret) + goto err_disable_buffers; + } + + return 0; + +err_disable_buffers: + list_for_each_entry_continue_reverse(buf, &hwc->buffers, head) + iio_update_buffers(buf->indio_dev, NULL, &buf->buffer); + return ret; +} +EXPORT_SYMBOL_GPL(iio_hw_consumer_enable); + +/** + * iio_hw_consumer_disable() - Disable IIO hardware consumer + * @hwc: iio_hw_consumer to disable. + */ +void iio_hw_consumer_disable(struct iio_hw_consumer *hwc) +{ + struct hw_consumer_buffer *buf; + + list_for_each_entry(buf, &hwc->buffers, head) + iio_update_buffers(buf->indio_dev, NULL, &buf->buffer); +} +EXPORT_SYMBOL_GPL(iio_hw_consumer_disable); + +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); +MODULE_DESCRIPTION("Hardware consumer buffer the IIO framework"); +MODULE_LICENSE("GPL v2"); |