1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2012 Analog Devices, Inc.
4 * Author: Lars-Peter Clausen <lars@metafoo.de>
5 */
6
7 #include <linux/kernel.h>
8 #include <linux/export.h>
9 #include <linux/module.h>
10 #include <linux/iio/iio.h>
11 #include <linux/iio/buffer.h>
12 #include <linux/iio/buffer_impl.h>
13 #include <linux/iio/kfifo_buf.h>
14 #include <linux/iio/triggered_buffer.h>
15 #include <linux/iio/trigger_consumer.h>
16
17 /**
18 * iio_triggered_buffer_setup_ext() - Setup triggered buffer and pollfunc
19 * @indio_dev: IIO device structure
20 * @h: Function which will be used as pollfunc top half
21 * @thread: Function which will be used as pollfunc bottom half
22 * @direction: Direction of the data stream (in/out).
23 * @setup_ops: Buffer setup functions to use for this device.
24 * If NULL the default setup functions for triggered
25 * buffers will be used.
26 * @buffer_attrs: Extra sysfs buffer attributes for this IIO buffer
27 *
28 * This function combines some common tasks which will normally be performed
29 * when setting up a triggered buffer. It will allocate the buffer and the
30 * pollfunc.
31 *
32 * Before calling this function the indio_dev structure should already be
33 * completely initialized, but not yet registered. In practice this means that
34 * this function should be called right before iio_device_register().
35 *
36 * To free the resources allocated by this function call
37 * iio_triggered_buffer_cleanup().
38 */
iio_triggered_buffer_setup_ext(struct iio_dev * indio_dev,irqreturn_t (* h)(int irq,void * p),irqreturn_t (* thread)(int irq,void * p),enum iio_buffer_direction direction,const struct iio_buffer_setup_ops * setup_ops,const struct attribute ** buffer_attrs)39 int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev,
40 irqreturn_t (*h)(int irq, void *p),
41 irqreturn_t (*thread)(int irq, void *p),
42 enum iio_buffer_direction direction,
43 const struct iio_buffer_setup_ops *setup_ops,
44 const struct attribute **buffer_attrs)
45 {
46 struct iio_buffer *buffer;
47 int ret;
48
49 buffer = iio_kfifo_allocate();
50 if (!buffer) {
51 ret = -ENOMEM;
52 goto error_ret;
53 }
54
55 indio_dev->pollfunc = iio_alloc_pollfunc(h,
56 thread,
57 IRQF_ONESHOT,
58 indio_dev,
59 "%s_consumer%d",
60 indio_dev->name,
61 iio_device_id(indio_dev));
62 if (indio_dev->pollfunc == NULL) {
63 ret = -ENOMEM;
64 goto error_kfifo_free;
65 }
66
67 /* Ring buffer functions - here trigger setup related */
68 indio_dev->setup_ops = setup_ops;
69
70 /* Flag that polled ring buffering is possible */
71 indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
72
73 buffer->direction = direction;
74 buffer->attrs = buffer_attrs;
75
76 ret = iio_device_attach_buffer(indio_dev, buffer);
77 if (ret < 0)
78 goto error_dealloc_pollfunc;
79
80 return 0;
81
82 error_dealloc_pollfunc:
83 iio_dealloc_pollfunc(indio_dev->pollfunc);
84 error_kfifo_free:
85 iio_kfifo_free(buffer);
86 error_ret:
87 return ret;
88 }
89 EXPORT_SYMBOL(iio_triggered_buffer_setup_ext);
90
91 /**
92 * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup_ext()
93 * @indio_dev: IIO device structure
94 */
iio_triggered_buffer_cleanup(struct iio_dev * indio_dev)95 void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
96 {
97 iio_dealloc_pollfunc(indio_dev->pollfunc);
98 iio_kfifo_free(indio_dev->buffer);
99 }
100 EXPORT_SYMBOL(iio_triggered_buffer_cleanup);
101
devm_iio_triggered_buffer_clean(void * indio_dev)102 static void devm_iio_triggered_buffer_clean(void *indio_dev)
103 {
104 iio_triggered_buffer_cleanup(indio_dev);
105 }
106
devm_iio_triggered_buffer_setup_ext(struct device * dev,struct iio_dev * indio_dev,irqreturn_t (* h)(int irq,void * p),irqreturn_t (* thread)(int irq,void * p),enum iio_buffer_direction direction,const struct iio_buffer_setup_ops * ops,const struct attribute ** buffer_attrs)107 int devm_iio_triggered_buffer_setup_ext(struct device *dev,
108 struct iio_dev *indio_dev,
109 irqreturn_t (*h)(int irq, void *p),
110 irqreturn_t (*thread)(int irq, void *p),
111 enum iio_buffer_direction direction,
112 const struct iio_buffer_setup_ops *ops,
113 const struct attribute **buffer_attrs)
114 {
115 int ret;
116
117 ret = iio_triggered_buffer_setup_ext(indio_dev, h, thread, direction,
118 ops, buffer_attrs);
119 if (ret)
120 return ret;
121
122 return devm_add_action_or_reset(dev, devm_iio_triggered_buffer_clean,
123 indio_dev);
124 }
125 EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup_ext);
126
127 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
128 MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
129 MODULE_LICENSE("GPL");
130