v4.19.13 snapshot.
diff --git a/drivers/iio/buffer/industrialio-triggered-buffer.c b/drivers/iio/buffer/industrialio-triggered-buffer.c
new file mode 100644
index 0000000..d3db1fc
--- /dev/null
+++ b/drivers/iio/buffer/industrialio-triggered-buffer.c
@@ -0,0 +1,145 @@
+ /*
+ * Copyright (c) 2012 Analog Devices, Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = {
+ .postenable = &iio_triggered_buffer_postenable,
+ .predisable = &iio_triggered_buffer_predisable,
+};
+
+/**
+ * iio_triggered_buffer_setup() - Setup triggered buffer and pollfunc
+ * @indio_dev: IIO device structure
+ * @h: Function which will be used as pollfunc top half
+ * @thread: Function which will be used as pollfunc bottom half
+ * @setup_ops: Buffer setup functions to use for this device.
+ * If NULL the default setup functions for triggered
+ * buffers will be used.
+ *
+ * This function combines some common tasks which will normally be performed
+ * when setting up a triggered buffer. It will allocate the buffer and the
+ * pollfunc.
+ *
+ * Before calling this function the indio_dev structure should already be
+ * completely initialized, but not yet registered. In practice this means that
+ * this function should be called right before iio_device_register().
+ *
+ * To free the resources allocated by this function call
+ * iio_triggered_buffer_cleanup().
+ */
+int iio_triggered_buffer_setup(struct iio_dev *indio_dev,
+ irqreturn_t (*h)(int irq, void *p),
+ irqreturn_t (*thread)(int irq, void *p),
+ const struct iio_buffer_setup_ops *setup_ops)
+{
+ struct iio_buffer *buffer;
+ int ret;
+
+ buffer = iio_kfifo_allocate();
+ if (!buffer) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+
+ iio_device_attach_buffer(indio_dev, buffer);
+
+ indio_dev->pollfunc = iio_alloc_pollfunc(h,
+ thread,
+ IRQF_ONESHOT,
+ indio_dev,
+ "%s_consumer%d",
+ indio_dev->name,
+ indio_dev->id);
+ if (indio_dev->pollfunc == NULL) {
+ ret = -ENOMEM;
+ goto error_kfifo_free;
+ }
+
+ /* Ring buffer functions - here trigger setup related */
+ if (setup_ops)
+ indio_dev->setup_ops = setup_ops;
+ else
+ indio_dev->setup_ops = &iio_triggered_buffer_setup_ops;
+
+ /* Flag that polled ring buffering is possible */
+ indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
+
+ return 0;
+
+error_kfifo_free:
+ iio_kfifo_free(indio_dev->buffer);
+error_ret:
+ return ret;
+}
+EXPORT_SYMBOL(iio_triggered_buffer_setup);
+
+/**
+ * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup()
+ * @indio_dev: IIO device structure
+ */
+void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
+{
+ iio_dealloc_pollfunc(indio_dev->pollfunc);
+ iio_kfifo_free(indio_dev->buffer);
+}
+EXPORT_SYMBOL(iio_triggered_buffer_cleanup);
+
+static void devm_iio_triggered_buffer_clean(struct device *dev, void *res)
+{
+ iio_triggered_buffer_cleanup(*(struct iio_dev **)res);
+}
+
+int devm_iio_triggered_buffer_setup(struct device *dev,
+ struct iio_dev *indio_dev,
+ irqreturn_t (*h)(int irq, void *p),
+ irqreturn_t (*thread)(int irq, void *p),
+ const struct iio_buffer_setup_ops *ops)
+{
+ struct iio_dev **ptr;
+ int ret;
+
+ ptr = devres_alloc(devm_iio_triggered_buffer_clean, sizeof(*ptr),
+ GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ *ptr = indio_dev;
+
+ ret = iio_triggered_buffer_setup(indio_dev, h, thread, ops);
+ if (!ret)
+ devres_add(dev, ptr);
+ else
+ devres_free(ptr);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup);
+
+void devm_iio_triggered_buffer_cleanup(struct device *dev,
+ struct iio_dev *indio_dev)
+{
+ int rc;
+
+ rc = devres_release(dev, devm_iio_triggered_buffer_clean,
+ devm_iio_device_match, indio_dev);
+ WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_cleanup);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
+MODULE_LICENSE("GPL");