1 /*
2  * STMicroelectronics gyroscopes 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_gyro.h"
25 
26 int st_gyro_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_gyro_buffer_preenable(struct iio_dev *indio_dev)
34 {
35 	return st_sensors_set_enable(indio_dev, true);
36 }
37 
38 static int st_gyro_buffer_postenable(struct iio_dev *indio_dev)
39 {
40 	int err;
41 	struct st_sensor_data *gdata = iio_priv(indio_dev);
42 
43 	gdata->buffer_data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
44 	if (gdata->buffer_data == NULL) {
45 		err = -ENOMEM;
46 		goto allocate_memory_error;
47 	}
48 
49 	err = st_sensors_set_axis_enable(indio_dev,
50 					(u8)indio_dev->active_scan_mask[0]);
51 	if (err < 0)
52 		goto st_gyro_buffer_postenable_error;
53 
54 	err = iio_triggered_buffer_postenable(indio_dev);
55 	if (err < 0)
56 		goto st_gyro_buffer_postenable_error;
57 
58 	return err;
59 
60 st_gyro_buffer_postenable_error:
61 	kfree(gdata->buffer_data);
62 allocate_memory_error:
63 	return err;
64 }
65 
66 static int st_gyro_buffer_predisable(struct iio_dev *indio_dev)
67 {
68 	int err;
69 	struct st_sensor_data *gdata = iio_priv(indio_dev);
70 
71 	err = iio_triggered_buffer_predisable(indio_dev);
72 	if (err < 0)
73 		goto st_gyro_buffer_predisable_error;
74 
75 	err = st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
76 	if (err < 0)
77 		goto st_gyro_buffer_predisable_error;
78 
79 	err = st_sensors_set_enable(indio_dev, false);
80 
81 st_gyro_buffer_predisable_error:
82 	kfree(gdata->buffer_data);
83 	return err;
84 }
85 
86 static const struct iio_buffer_setup_ops st_gyro_buffer_setup_ops = {
87 	.preenable = &st_gyro_buffer_preenable,
88 	.postenable = &st_gyro_buffer_postenable,
89 	.predisable = &st_gyro_buffer_predisable,
90 };
91 
92 int st_gyro_allocate_ring(struct iio_dev *indio_dev)
93 {
94 	return iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
95 		&st_sensors_trigger_handler, &st_gyro_buffer_setup_ops);
96 }
97 
98 void st_gyro_deallocate_ring(struct iio_dev *indio_dev)
99 {
100 	iio_triggered_buffer_cleanup(indio_dev);
101 }
102 
103 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
104 MODULE_DESCRIPTION("STMicroelectronics gyroscopes buffer");
105 MODULE_LICENSE("GPL v2");
106