summaryrefslogtreecommitdiff
path: root/drivers/iio/imu/adis_buffer.c
blob: fdfc0538734c5e781be9fd5b7183f3dfb51830b9 (plain)
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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Common library for ADIS16XXX devices
 *
 * Copyright 2012 Analog Devices Inc.
 *   Author: Lars-Peter Clausen <lars@metafoo.de>
 */

#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>

static int adis_update_scan_mode_burst(struct iio_dev *indio_dev,
				       const unsigned long *scan_mask)
{
	struct adis *adis = iio_device_get_drvdata(indio_dev);
	unsigned int burst_length, burst_max_length;
	u8 *tx;

	burst_length = adis->data->burst_len + adis->burst_extra_len;

	if (adis->data->burst_max_len)
		burst_max_length = adis->data->burst_max_len;
	else
		burst_max_length = burst_length;

	adis->xfer = kcalloc(2, sizeof(*adis->xfer), GFP_KERNEL);
	if (!adis->xfer)
		return -ENOMEM;

	adis->buffer = kzalloc(burst_max_length + sizeof(u16), GFP_KERNEL);
	if (!adis->buffer) {
		kfree(adis->xfer);
		adis->xfer = NULL;
		return -ENOMEM;
	}

	tx = adis->buffer + burst_max_length;
	tx[0] = ADIS_READ_REG(adis->data->burst_reg_cmd);
	tx[1] = 0;

	adis->xfer[0].tx_buf = tx;
	adis->xfer[0].bits_per_word = 8;
	adis->xfer[0].len = 2;
	if (adis->data->burst_max_speed_hz)
		adis->xfer[0].speed_hz = adis->data->burst_max_speed_hz;
	adis->xfer[1].rx_buf = adis->buffer;
	adis->xfer[1].bits_per_word = 8;
	adis->xfer[1].len = burst_length;
	if (adis->data->burst_max_speed_hz)
		adis->xfer[1].speed_hz = adis->data->burst_max_speed_hz;

	spi_message_init(&adis->msg);
	spi_message_add_tail(&adis->xfer[0], &adis->msg);
	spi_message_add_tail(&adis->xfer[1], &adis->msg);

	return 0;
}

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);

	if (adis->data->burst_len)
		return adis_update_scan_mode_burst(indio_dev, scan_mask);

	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 = kcalloc(indio_dev->scan_bytes, 2, GFP_KERNEL);
	if (!adis->buffer) {
		kfree(adis->xfer);
		adis->xfer = NULL;
		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.value = adis->data->read_delay;
		adis->xfer[j].delay.unit = SPI_DELAY_UNIT_USECS;
		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_NS_GPL(adis_update_scan_mode, "IIO_ADISLIB");

static int adis_paging_trigger_handler(struct adis *adis)
{
	int ret;

	guard(mutex)(&adis->state_lock);
	if (adis->current_page != 0) {
		adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID);
		adis->tx[1] = 0;
		ret = spi_write(adis->spi, adis->tx, 2);
		if (ret) {
			dev_err(&adis->spi->dev, "Failed to change device page: %d\n", ret);
			return ret;
		}

		adis->current_page = 0;
	}

	return spi_sync(adis->spi, &adis->msg);
}

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->data->has_paging)
		ret = adis_paging_trigger_handler(adis);
	else
		ret = spi_sync(adis->spi, &adis->msg);
	if (ret) {
		dev_err(&adis->spi->dev, "Failed to read data: %d", ret);
		goto irq_done;
	}

	iio_push_to_buffers_with_timestamp(indio_dev, adis->buffer,
					   pf->timestamp);

irq_done:
	iio_trigger_notify_done(indio_dev->trig);

	return IRQ_HANDLED;
}

static void adis_buffer_cleanup(void *arg)
{
	struct adis *adis = arg;

	kfree(adis->buffer);
	kfree(adis->xfer);
}

/**
 * devm_adis_setup_buffer_and_trigger_with_attrs() - Sets up buffer and trigger
 * for the managed adis device with buffer attributes.
 * @adis: The adis device
 * @indio_dev: The IIO device
 * @trigger_handler: Trigger handler: should handle the buffer readings.
 * @ops: Optional buffer setup functions, may be NULL.
 * @buffer_attrs: Extra buffer attributes.
 *
 * Returns 0 on success, a negative error code otherwise.
 *
 * This function sets up the buffer (with buffer setup functions and extra
 * buffer attributes) and trigger for a adis devices with buffer attributes.
 */
int
devm_adis_setup_buffer_and_trigger_with_attrs(struct adis *adis, struct iio_dev *indio_dev,
					      irq_handler_t trigger_handler,
					      const struct iio_buffer_setup_ops *ops,
					      const struct iio_dev_attr **buffer_attrs)
{
	int ret;

	if (!trigger_handler)
		trigger_handler = adis_trigger_handler;

	ret = devm_iio_triggered_buffer_setup_ext(&adis->spi->dev, indio_dev,
						  &iio_pollfunc_store_time,
						  trigger_handler,
						  IIO_BUFFER_DIRECTION_IN,
						  ops,
						  buffer_attrs);
	if (ret)
		return ret;

	if (adis->spi->irq) {
		ret = devm_adis_probe_trigger(adis, indio_dev);
		if (ret)
			return ret;
	}

	return devm_add_action_or_reset(&adis->spi->dev, adis_buffer_cleanup,
					adis);
}
EXPORT_SYMBOL_NS_GPL(devm_adis_setup_buffer_and_trigger_with_attrs, "IIO_ADISLIB");