1 /*
2  * STMicroelectronics magnetometers driver
3  *
4  * Copyright 2012-2013 STMicroelectronics Inc.
5  *
6  * Denis Ciocca <denis.ciocca@st.com>
7  *
8  * Licensed under the GPL-2.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/stat.h>
15 #include <linux/interrupt.h>
16 #include <linux/i2c.h>
17 #include <linux/delay.h>
18 #include <linux/iio/iio.h>
19 #include <linux/iio/buffer.h>
20 #include <linux/iio/trigger_consumer.h>
21 #include <linux/iio/triggered_buffer.h>
22 
23 #include <linux/iio/common/st_sensors.h>
24 #include "st_magn.h"
25 
26 int st_magn_trig_set_state(struct iio_trigger *trig, bool state)
27 {
28 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
29 
30 	return st_sensors_set_dataready_irq(indio_dev, state);
31 }
32 
33 static int st_magn_buffer_postenable(struct iio_dev *indio_dev)
34 {
35 	int err;
36 	struct st_sensor_data *mdata = iio_priv(indio_dev);
37 
38 	mdata->buffer_data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
39 	if (mdata->buffer_data == NULL) {
40 		err = -ENOMEM;
41 		goto allocate_memory_error;
42 	}
43 
44 	err = iio_triggered_buffer_postenable(indio_dev);
45 	if (err < 0)
46 		goto st_magn_buffer_postenable_error;
47 
48 	return st_sensors_set_enable(indio_dev, true);
49 
50 st_magn_buffer_postenable_error:
51 	kfree(mdata->buffer_data);
52 allocate_memory_error:
53 	return err;
54 }
55 
56 static int st_magn_buffer_predisable(struct iio_dev *indio_dev)
57 {
58 	int err;
59 	struct st_sensor_data *mdata = iio_priv(indio_dev);
60 
61 	err = st_sensors_set_enable(indio_dev, false);
62 	if (err < 0)
63 		goto st_magn_buffer_predisable_error;
64 
65 	err = iio_triggered_buffer_predisable(indio_dev);
66 
67 st_magn_buffer_predisable_error:
68 	kfree(mdata->buffer_data);
69 	return err;
70 }
71 
72 static const struct iio_buffer_setup_ops st_magn_buffer_setup_ops = {
73 	.postenable = &st_magn_buffer_postenable,
74 	.predisable = &st_magn_buffer_predisable,
75 };
76 
77 int st_magn_allocate_ring(struct iio_dev *indio_dev)
78 {
79 	return iio_triggered_buffer_setup(indio_dev, NULL,
80 		&st_sensors_trigger_handler, &st_magn_buffer_setup_ops);
81 }
82 
83 void st_magn_deallocate_ring(struct iio_dev *indio_dev)
84 {
85 	iio_triggered_buffer_cleanup(indio_dev);
86 }
87 
88 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
89 MODULE_DESCRIPTION("STMicroelectronics magnetometers buffer");
90 MODULE_LICENSE("GPL v2");
91