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 "adis16204.h"
12
13 /**
14 * adis16204_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 **/
adis16204_read_ring_data(struct device * dev,u8 * rx)18 static int adis16204_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 adis16204_state *st = iio_priv(indio_dev);
23 struct spi_transfer xfers[ADIS16204_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 <= ADIS16204_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 = 20;
37 xfers[i].tx_buf = st->tx + 2 * i;
38 st->tx[2 * i]
39 = ADIS16204_READ_REG(ADIS16204_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
55 /* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
56 * specific to be rolled into the core.
57 */
adis16204_trigger_handler(int irq,void * p)58 static irqreturn_t adis16204_trigger_handler(int irq, void *p)
59 {
60 struct iio_poll_func *pf = p;
61 struct iio_dev *indio_dev = pf->indio_dev;
62 struct adis16204_state *st = iio_priv(indio_dev);
63 struct iio_buffer *ring = indio_dev->buffer;
64 int i = 0;
65 s16 *data;
66 size_t datasize = ring->access->get_bytes_per_datum(ring);
67
68 data = kmalloc(datasize, GFP_KERNEL);
69 if (data == NULL) {
70 dev_err(&st->us->dev, "memory alloc failed in ring bh");
71 return -ENOMEM;
72 }
73
74 if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength) &&
75 adis16204_read_ring_data(&indio_dev->dev, st->rx) >= 0)
76 for (; i < bitmap_weight(indio_dev->active_scan_mask,
77 indio_dev->masklength); i++)
78 data[i] = be16_to_cpup((__be16 *)&(st->rx[i*2]));
79
80 /* Guaranteed to be aligned with 8 byte boundary */
81 if (ring->scan_timestamp)
82 *((s64 *)(data + ((i + 3)/4)*4)) = pf->timestamp;
83
84 ring->access->store_to(ring, (u8 *)data, pf->timestamp);
85
86 iio_trigger_notify_done(indio_dev->trig);
87 kfree(data);
88
89 return IRQ_HANDLED;
90 }
91
adis16204_unconfigure_ring(struct iio_dev * indio_dev)92 void adis16204_unconfigure_ring(struct iio_dev *indio_dev)
93 {
94 iio_dealloc_pollfunc(indio_dev->pollfunc);
95 iio_sw_rb_free(indio_dev->buffer);
96 }
97
98 static const struct iio_buffer_setup_ops adis16204_ring_setup_ops = {
99 .preenable = &iio_sw_buffer_preenable,
100 .postenable = &iio_triggered_buffer_postenable,
101 .predisable = &iio_triggered_buffer_predisable,
102 };
103
adis16204_configure_ring(struct iio_dev * indio_dev)104 int adis16204_configure_ring(struct iio_dev *indio_dev)
105 {
106 int ret = 0;
107 struct iio_buffer *ring;
108
109 ring = iio_sw_rb_allocate(indio_dev);
110 if (!ring) {
111 ret = -ENOMEM;
112 return ret;
113 }
114 indio_dev->buffer = ring;
115 /* Effectively select the ring buffer implementation */
116 ring->access = &ring_sw_access_funcs;
117 ring->scan_timestamp = true;
118 indio_dev->setup_ops = &adis16204_ring_setup_ops;
119
120 indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
121 &adis16204_trigger_handler,
122 IRQF_ONESHOT,
123 indio_dev,
124 "%s_consumer%d",
125 indio_dev->name,
126 indio_dev->id);
127 if (indio_dev->pollfunc == NULL) {
128 ret = -ENOMEM;
129 goto error_iio_sw_rb_free;
130 }
131
132 indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
133 return 0;
134
135 error_iio_sw_rb_free:
136 iio_sw_rb_free(indio_dev->buffer);
137 return ret;
138 }
139