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
26static int st_magn_buffer_preenable(struct iio_dev *indio_dev)
27{
28	return st_sensors_set_enable(indio_dev, true);
29}
30
31static int st_magn_buffer_postenable(struct iio_dev *indio_dev)
32{
33	int err;
34	struct st_sensor_data *mdata = iio_priv(indio_dev);
35
36	mdata->buffer_data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
37	if (mdata->buffer_data == NULL) {
38		err = -ENOMEM;
39		goto allocate_memory_error;
40	}
41
42	err = iio_triggered_buffer_postenable(indio_dev);
43	if (err < 0)
44		goto st_magn_buffer_postenable_error;
45
46	return err;
47
48st_magn_buffer_postenable_error:
49	kfree(mdata->buffer_data);
50allocate_memory_error:
51	return err;
52}
53
54static int st_magn_buffer_predisable(struct iio_dev *indio_dev)
55{
56	int err;
57	struct st_sensor_data *mdata = iio_priv(indio_dev);
58
59	err = iio_triggered_buffer_predisable(indio_dev);
60	if (err < 0)
61		goto st_magn_buffer_predisable_error;
62
63	err = st_sensors_set_enable(indio_dev, false);
64
65st_magn_buffer_predisable_error:
66	kfree(mdata->buffer_data);
67	return err;
68}
69
70static const struct iio_buffer_setup_ops st_magn_buffer_setup_ops = {
71	.preenable = &st_magn_buffer_preenable,
72	.postenable = &st_magn_buffer_postenable,
73	.predisable = &st_magn_buffer_predisable,
74};
75
76int st_magn_allocate_ring(struct iio_dev *indio_dev)
77{
78	return iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
79		&st_sensors_trigger_handler, &st_magn_buffer_setup_ops);
80}
81
82void st_magn_deallocate_ring(struct iio_dev *indio_dev)
83{
84	iio_triggered_buffer_cleanup(indio_dev);
85}
86
87MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
88MODULE_DESCRIPTION("STMicroelectronics magnetometers buffer");
89MODULE_LICENSE("GPL v2");
90