1#include <linux/export.h>
2#include <linux/interrupt.h>
3#include <linux/mutex.h>
4#include <linux/kernel.h>
5#include <linux/spi/spi.h>
6#include <linux/slab.h>
7
8#include "../iio.h"
9#include "../ring_sw.h"
10#include "../trigger_consumer.h"
11#include "adis16240.h"
12
13/**
14 * adis16240_read_ring_data() read data registers which will be placed into ring
15 * @dev: device associated with child of actual device (iio_dev or iio_trig)
16 * @rx: somewhere to pass back the value read
17 **/
18static int adis16240_read_ring_data(struct device *dev, u8 *rx)
19{
20	struct spi_message msg;
21	struct iio_dev *indio_dev = dev_get_drvdata(dev);
22	struct adis16240_state *st = iio_priv(indio_dev);
23	struct spi_transfer xfers[ADIS16240_OUTPUTS + 1];
24	int ret;
25	int i;
26
27	mutex_lock(&st->buf_lock);
28
29	spi_message_init(&msg);
30
31	memset(xfers, 0, sizeof(xfers));
32	for (i = 0; i <= ADIS16240_OUTPUTS; i++) {
33		xfers[i].bits_per_word = 8;
34		xfers[i].cs_change = 1;
35		xfers[i].len = 2;
36		xfers[i].delay_usecs = 30;
37		xfers[i].tx_buf = st->tx + 2 * i;
38		st->tx[2 * i]
39			= ADIS16240_READ_REG(ADIS16240_SUPPLY_OUT + 2 * i);
40		st->tx[2 * i + 1] = 0;
41		if (i >= 1)
42			xfers[i].rx_buf = rx + 2 * (i - 1);
43		spi_message_add_tail(&xfers[i], &msg);
44	}
45
46	ret = spi_sync(st->us, &msg);
47	if (ret)
48		dev_err(&st->us->dev, "problem when burst reading");
49
50	mutex_unlock(&st->buf_lock);
51
52	return ret;
53}
54
55static irqreturn_t adis16240_trigger_handler(int irq, void *p)
56{
57	struct iio_poll_func *pf = p;
58	struct iio_dev *indio_dev = pf->indio_dev;
59	struct adis16240_state *st = iio_priv(indio_dev);
60	struct iio_buffer *ring = indio_dev->buffer;
61
62	int i = 0;
63	s16 *data;
64	size_t datasize = ring->access->get_bytes_per_datum(ring);
65
66	data = kmalloc(datasize, GFP_KERNEL);
67	if (data == NULL) {
68		dev_err(&st->us->dev, "memory alloc failed in ring bh");
69		return -ENOMEM;
70	}
71
72	if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength) &&
73	    adis16240_read_ring_data(&indio_dev->dev, st->rx) >= 0)
74		for (; i < bitmap_weight(indio_dev->active_scan_mask,
75					 indio_dev->masklength); i++)
76			data[i] = be16_to_cpup((__be16 *)&(st->rx[i*2]));
77
78	/* Guaranteed to be aligned with 8 byte boundary */
79	if (ring->scan_timestamp)
80		*((s64 *)(data + ((i + 3)/4)*4)) = pf->timestamp;
81
82	ring->access->store_to(ring, (u8 *)data, pf->timestamp);
83
84	iio_trigger_notify_done(indio_dev->trig);
85	kfree(data);
86
87	return IRQ_HANDLED;
88}
89
90void adis16240_unconfigure_ring(struct iio_dev *indio_dev)
91{
92	iio_dealloc_pollfunc(indio_dev->pollfunc);
93	iio_sw_rb_free(indio_dev->buffer);
94}
95
96static const struct iio_buffer_setup_ops adis16240_ring_setup_ops = {
97	.preenable = &iio_sw_buffer_preenable,
98	.postenable = &iio_triggered_buffer_postenable,
99	.predisable = &iio_triggered_buffer_predisable,
100};
101
102int adis16240_configure_ring(struct iio_dev *indio_dev)
103{
104	int ret = 0;
105	struct iio_buffer *ring;
106
107	ring = iio_sw_rb_allocate(indio_dev);
108	if (!ring) {
109		ret = -ENOMEM;
110		return ret;
111	}
112	indio_dev->buffer = ring;
113	ring->scan_timestamp = true;
114	indio_dev->setup_ops = &adis16240_ring_setup_ops;
115
116	indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
117						 &adis16240_trigger_handler,
118						 IRQF_ONESHOT,
119						 indio_dev,
120						 "%s_consumer%d",
121						 indio_dev->name,
122						 indio_dev->id);
123	if (indio_dev->pollfunc == NULL) {
124		ret = -ENOMEM;
125		goto error_iio_sw_rb_free;
126	}
127
128	indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
129	return 0;
130
131error_iio_sw_rb_free:
132	iio_sw_rb_free(indio_dev->buffer);
133	return ret;
134}
135