/drivers/staging/iio/accel/adis16240_ring.c
C | 152 lines | 120 code | 24 blank | 8 comment | 11 complexity | 8f87dddbcda45d2e3144c17f9860129f MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.0, AGPL-1.0
1#include <linux/interrupt.h>
2#include <linux/irq.h>
3#include <linux/gpio.h>
4#include <linux/workqueue.h>
5#include <linux/mutex.h>
6#include <linux/device.h>
7#include <linux/kernel.h>
8#include <linux/spi/spi.h>
9#include <linux/slab.h>
10#include <linux/sysfs.h>
11#include <linux/list.h>
12
13#include "../iio.h"
14#include "../sysfs.h"
15#include "../ring_sw.h"
16#include "accel.h"
17#include "../trigger.h"
18#include "adis16240.h"
19
20/**
21 * adis16240_read_ring_data() read data registers which will be placed into ring
22 * @dev: device associated with child of actual device (iio_dev or iio_trig)
23 * @rx: somewhere to pass back the value read
24 **/
25static int adis16240_read_ring_data(struct device *dev, u8 *rx)
26{
27 struct spi_message msg;
28 struct iio_dev *indio_dev = dev_get_drvdata(dev);
29 struct adis16240_state *st = iio_dev_get_devdata(indio_dev);
30 struct spi_transfer xfers[ADIS16240_OUTPUTS + 1];
31 int ret;
32 int i;
33
34 mutex_lock(&st->buf_lock);
35
36 spi_message_init(&msg);
37
38 memset(xfers, 0, sizeof(xfers));
39 for (i = 0; i <= ADIS16240_OUTPUTS; i++) {
40 xfers[i].bits_per_word = 8;
41 xfers[i].cs_change = 1;
42 xfers[i].len = 2;
43 xfers[i].delay_usecs = 30;
44 xfers[i].tx_buf = st->tx + 2 * i;
45 st->tx[2 * i]
46 = ADIS16240_READ_REG(ADIS16240_SUPPLY_OUT + 2 * i);
47 st->tx[2 * i + 1] = 0;
48 if (i >= 1)
49 xfers[i].rx_buf = rx + 2 * (i - 1);
50 spi_message_add_tail(&xfers[i], &msg);
51 }
52
53 ret = spi_sync(st->us, &msg);
54 if (ret)
55 dev_err(&st->us->dev, "problem when burst reading");
56
57 mutex_unlock(&st->buf_lock);
58
59 return ret;
60}
61
62static irqreturn_t adis16240_trigger_handler(int irq, void *p)
63{
64 struct iio_poll_func *pf = p;
65 struct iio_dev *indio_dev = pf->private_data;
66 struct adis16240_state *st = iio_dev_get_devdata(indio_dev);
67 struct iio_ring_buffer *ring = indio_dev->ring;
68
69 int i = 0;
70 s16 *data;
71 size_t datasize = ring->access->get_bytes_per_datum(ring);
72
73 data = kmalloc(datasize, GFP_KERNEL);
74 if (data == NULL) {
75 dev_err(&st->us->dev, "memory alloc failed in ring bh");
76 return -ENOMEM;
77 }
78
79 if (ring->scan_count &&
80 adis16240_read_ring_data(&st->indio_dev->dev, st->rx) >= 0)
81 for (; i < ring->scan_count; i++)
82 data[i] = be16_to_cpup((__be16 *)&(st->rx[i*2]));
83
84 /* Guaranteed to be aligned with 8 byte boundary */
85 if (ring->scan_timestamp)
86 *((s64 *)(data + ((i + 3)/4)*4)) = pf->timestamp;
87
88 ring->access->store_to(ring, (u8 *)data, pf->timestamp);
89
90 iio_trigger_notify_done(st->indio_dev->trig);
91 kfree(data);
92
93 return IRQ_HANDLED;
94}
95
96void adis16240_unconfigure_ring(struct iio_dev *indio_dev)
97{
98 iio_dealloc_pollfunc(indio_dev->pollfunc);
99 iio_sw_rb_free(indio_dev->ring);
100}
101
102static const struct iio_ring_setup_ops adis16240_ring_setup_ops = {
103 .preenable = &iio_sw_ring_preenable,
104 .postenable = &iio_triggered_ring_postenable,
105 .predisable = &iio_triggered_ring_predisable,
106};
107
108int adis16240_configure_ring(struct iio_dev *indio_dev)
109{
110 int ret = 0;
111 struct iio_ring_buffer *ring;
112
113 ring = iio_sw_rb_allocate(indio_dev);
114 if (!ring) {
115 ret = -ENOMEM;
116 return ret;
117 }
118 indio_dev->ring = ring;
119 /* Effectively select the ring buffer implementation */
120 ring->access = &ring_sw_access_funcs;
121 ring->bpe = 2;
122 ring->scan_timestamp = true;
123 ring->setup_ops = &adis16240_ring_setup_ops;
124 ring->owner = THIS_MODULE;
125
126 /* Set default scan mode */
127 iio_scan_mask_set(ring, ADIS16240_SCAN_SUPPLY);
128 iio_scan_mask_set(ring, ADIS16240_SCAN_ACC_X);
129 iio_scan_mask_set(ring, ADIS16240_SCAN_ACC_Y);
130 iio_scan_mask_set(ring, ADIS16240_SCAN_ACC_Z);
131 iio_scan_mask_set(ring, ADIS16240_SCAN_AUX_ADC);
132 iio_scan_mask_set(ring, ADIS16240_SCAN_TEMP);
133
134 indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
135 &adis16240_trigger_handler,
136 IRQF_ONESHOT,
137 indio_dev,
138 "%s_consumer%d",
139 indio_dev->name,
140 indio_dev->id);
141 if (indio_dev->pollfunc == NULL) {
142 ret = -ENOMEM;
143 goto error_iio_sw_rb_free;
144 }
145
146 indio_dev->modes |= INDIO_RING_TRIGGERED;
147 return 0;
148
149error_iio_sw_rb_free:
150 iio_sw_rb_free(indio_dev->ring);
151 return ret;
152}