These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / iio / buffer / industrialio-triggered-buffer.c

diff --git a/kernel/drivers/iio/buffer/industrialio-triggered-buffer.c b/kernel/drivers/iio/buffer/industrialio-triggered-buffer.c
new file mode 100644 (file)
index 0000000..4b2858b
--- /dev/null
+++ b/kernel/drivers/iio/buffer/industrialio-triggered-buffer.c
@@ -0,0 +1,103 @@
+ /*
+ * 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);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
+MODULE_LICENSE("GPL");