adis_buffer.c
4.24 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
/*
* Common library for ADIS16XXX devices
*
* Copyright 2012 Analog Devices Inc.
* Author: Lars-Peter Clausen <lars@metafoo.de>
*
* Licensed under the GPL-2 or later.
*/
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/imu/adis.h>
int adis_update_scan_mode(struct iio_dev *indio_dev,
const unsigned long *scan_mask)
{
struct adis *adis = iio_device_get_drvdata(indio_dev);
const struct iio_chan_spec *chan;
unsigned int scan_count;
unsigned int i, j;
__be16 *tx, *rx;
kfree(adis->xfer);
kfree(adis->buffer);
scan_count = indio_dev->scan_bytes / 2;
adis->xfer = kcalloc(scan_count + 1, sizeof(*adis->xfer), GFP_KERNEL);
if (!adis->xfer)
return -ENOMEM;
adis->buffer = kzalloc(indio_dev->scan_bytes * 2, GFP_KERNEL);
if (!adis->buffer)
return -ENOMEM;
rx = adis->buffer;
tx = rx + scan_count;
spi_message_init(&adis->msg);
for (j = 0; j <= scan_count; j++) {
adis->xfer[j].bits_per_word = 8;
if (j != scan_count)
adis->xfer[j].cs_change = 1;
adis->xfer[j].len = 2;
adis->xfer[j].delay_usecs = adis->data->read_delay;
if (j < scan_count)
adis->xfer[j].tx_buf = &tx[j];
if (j >= 1)
adis->xfer[j].rx_buf = &rx[j - 1];
spi_message_add_tail(&adis->xfer[j], &adis->msg);
}
chan = indio_dev->channels;
for (i = 0; i < indio_dev->num_channels; i++, chan++) {
if (!test_bit(chan->scan_index, scan_mask))
continue;
if (chan->scan_type.storagebits == 32)
*tx++ = cpu_to_be16((chan->address + 2) << 8);
*tx++ = cpu_to_be16(chan->address << 8);
}
return 0;
}
EXPORT_SYMBOL_GPL(adis_update_scan_mode);
static irqreturn_t adis_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct adis *adis = iio_device_get_drvdata(indio_dev);
int ret;
if (!adis->buffer)
return -ENOMEM;
if (adis->data->has_paging) {
mutex_lock(&adis->txrx_lock);
if (adis->current_page != 0) {
adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID);
adis->tx[1] = 0;
spi_write(adis->spi, adis->tx, 2);
}
}
ret = spi_sync(adis->spi, &adis->msg);
if (ret)
dev_err(&adis->spi->dev, "Failed to read data: %d", ret);
if (adis->data->has_paging) {
adis->current_page = 0;
mutex_unlock(&adis->txrx_lock);
}
iio_push_to_buffers_with_timestamp(indio_dev, adis->buffer,
pf->timestamp);
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
/**
* adis_setup_buffer_and_trigger() - Sets up buffer and trigger for the adis device
* @adis: The adis device.
* @indio_dev: The IIO device.
* @trigger_handler: Optional trigger handler, may be NULL.
*
* Returns 0 on success, a negative error code otherwise.
*
* This function sets up the buffer and trigger for a adis devices. If
* 'trigger_handler' is NULL the default trigger handler will be used. The
* default trigger handler will simply read the registers assigned to the
* currently active channels.
*
* adis_cleanup_buffer_and_trigger() should be called to free the resources
* allocated by this function.
*/
int adis_setup_buffer_and_trigger(struct adis *adis, struct iio_dev *indio_dev,
irqreturn_t (*trigger_handler)(int, void *))
{
int ret;
if (!trigger_handler)
trigger_handler = adis_trigger_handler;
ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
trigger_handler, NULL);
if (ret)
return ret;
if (adis->spi->irq) {
ret = adis_probe_trigger(adis, indio_dev);
if (ret)
goto error_buffer_cleanup;
}
return 0;
error_buffer_cleanup:
iio_triggered_buffer_cleanup(indio_dev);
return ret;
}
EXPORT_SYMBOL_GPL(adis_setup_buffer_and_trigger);
/**
* adis_cleanup_buffer_and_trigger() - Free buffer and trigger resources
* @adis: The adis device.
* @indio_dev: The IIO device.
*
* Frees resources allocated by adis_setup_buffer_and_trigger()
*/
void adis_cleanup_buffer_and_trigger(struct adis *adis,
struct iio_dev *indio_dev)
{
if (adis->spi->irq)
adis_remove_trigger(adis);
kfree(adis->buffer);
kfree(adis->xfer);
iio_triggered_buffer_cleanup(indio_dev);
}
EXPORT_SYMBOL_GPL(adis_cleanup_buffer_and_trigger);