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path: root/drivers/iio/buffer/industrialio-hw-consumer.c
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-rw-r--r--drivers/iio/buffer/industrialio-hw-consumer.c213
1 files changed, 213 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..fb58f599a
--- /dev/null
+++ b/drivers/iio/buffer/industrialio-hw-consumer.c
@@ -0,0 +1,213 @@
+// 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)
+{
+ struct hw_consumer_buffer *buf;
+
+ list_for_each_entry(buf, &hwc->buffers, head) {
+ if (buf->indio_dev == indio_dev)
+ return buf;
+ }
+
+ buf = kzalloc(struct_size(buf, scan_mask, BITS_TO_LONGS(indio_dev->masklength)),
+ 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(void *iio_hwc)
+{
+ iio_hw_consumer_free(iio_hwc);
+}
+
+/**
+ * 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.
+ *
+ * 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 *iio_hwc;
+ int ret;
+
+ iio_hwc = iio_hw_consumer_alloc(dev);
+ if (IS_ERR(iio_hwc))
+ return iio_hwc;
+
+ ret = devm_add_action_or_reset(dev, devm_iio_hw_consumer_release,
+ iio_hwc);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return iio_hwc;
+}
+EXPORT_SYMBOL_GPL(devm_iio_hw_consumer_alloc);
+
+/**
+ * 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");