xref: /linux/drivers/iio/magnetometer/st_magn_buffer.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * STMicroelectronics magnetometers driver
4  *
5  * Copyright 2012-2013 STMicroelectronics Inc.
6  *
7  * Denis Ciocca <denis.ciocca@st.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/stat.h>
14 #include <linux/interrupt.h>
15 #include <linux/i2c.h>
16 #include <linux/delay.h>
17 #include <linux/iio/iio.h>
18 #include <linux/iio/buffer.h>
19 #include <linux/iio/trigger_consumer.h>
20 #include <linux/iio/triggered_buffer.h>
21 
22 #include <linux/iio/common/st_sensors.h>
23 #include "st_magn.h"
24 
25 int st_magn_trig_set_state(struct iio_trigger *trig, bool state)
26 {
27 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
28 
29 	return st_sensors_set_dataready_irq(indio_dev, state);
30 }
31 
32 static int st_magn_buffer_postenable(struct iio_dev *indio_dev)
33 {
34 	int err;
35 
36 	err = iio_triggered_buffer_postenable(indio_dev);
37 	if (err < 0)
38 		return err;
39 
40 	err = st_sensors_set_enable(indio_dev, true);
41 	if (err < 0)
42 		goto st_magn_buffer_predisable;
43 
44 	return 0;
45 
46 st_magn_buffer_predisable:
47 	iio_triggered_buffer_predisable(indio_dev);
48 	return err;
49 }
50 
51 static int st_magn_buffer_predisable(struct iio_dev *indio_dev)
52 {
53 	int err, err2;
54 
55 	err = st_sensors_set_enable(indio_dev, false);
56 
57 	err2 = iio_triggered_buffer_predisable(indio_dev);
58 	if (!err)
59 		err = err2;
60 
61 	return err;
62 }
63 
64 static const struct iio_buffer_setup_ops st_magn_buffer_setup_ops = {
65 	.postenable = &st_magn_buffer_postenable,
66 	.predisable = &st_magn_buffer_predisable,
67 };
68 
69 int st_magn_allocate_ring(struct iio_dev *indio_dev)
70 {
71 	return iio_triggered_buffer_setup(indio_dev, NULL,
72 		&st_sensors_trigger_handler, &st_magn_buffer_setup_ops);
73 }
74 
75 void st_magn_deallocate_ring(struct iio_dev *indio_dev)
76 {
77 	iio_triggered_buffer_cleanup(indio_dev);
78 }
79 
80 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
81 MODULE_DESCRIPTION("STMicroelectronics magnetometers buffer");
82 MODULE_LICENSE("GPL v2");
83