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 "adis16260.h"
12 
13 /**
14  * adis16260_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  **/
adis16260_read_ring_data(struct device * dev,u8 * rx)18 static int adis16260_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 adis16260_state *st = iio_priv(indio_dev);
23 	struct spi_transfer xfers[ADIS16260_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 <= ADIS16260_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 		if (i < 2) /* SUPPLY_OUT:0x02 GYRO_OUT:0x04 */
39 			st->tx[2 * i]
40 				= ADIS16260_READ_REG(ADIS16260_SUPPLY_OUT
41 						+ 2 * i);
42 		else /* 0x06 to 0x09 is reserved */
43 			st->tx[2 * i]
44 				= ADIS16260_READ_REG(ADIS16260_SUPPLY_OUT
45 						+ 2 * i + 4);
46 		st->tx[2 * i + 1] = 0;
47 		if (i >= 1)
48 			xfers[i].rx_buf = rx + 2 * (i - 1);
49 		spi_message_add_tail(&xfers[i], &msg);
50 	}
51 
52 	ret = spi_sync(st->us, &msg);
53 	if (ret)
54 		dev_err(&st->us->dev, "problem when burst reading");
55 
56 	mutex_unlock(&st->buf_lock);
57 
58 	return ret;
59 }
60 
adis16260_trigger_handler(int irq,void * p)61 static irqreturn_t adis16260_trigger_handler(int irq, void *p)
62 {
63 	struct iio_poll_func *pf = p;
64 	struct iio_dev *indio_dev = pf->indio_dev;
65 	struct adis16260_state *st = iio_priv(indio_dev);
66 	struct iio_buffer *ring = indio_dev->buffer;
67 	int i = 0;
68 	s16 *data;
69 	size_t datasize = ring->access->get_bytes_per_datum(ring);
70 
71 	data = kmalloc(datasize , GFP_KERNEL);
72 	if (data == NULL) {
73 		dev_err(&st->us->dev, "memory alloc failed in ring bh");
74 		return -ENOMEM;
75 	}
76 
77 	if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength) &&
78 	    adis16260_read_ring_data(&indio_dev->dev, st->rx) >= 0)
79 		for (; i < bitmap_weight(indio_dev->active_scan_mask,
80 					 indio_dev->masklength); i++)
81 			data[i] = be16_to_cpup((__be16 *)&(st->rx[i*2]));
82 
83 	/* Guaranteed to be aligned with 8 byte boundary */
84 	if (ring->scan_timestamp)
85 		*((s64 *)(data + ((i + 3)/4)*4)) = pf->timestamp;
86 
87 	ring->access->store_to(ring, (u8 *)data, pf->timestamp);
88 
89 	iio_trigger_notify_done(indio_dev->trig);
90 	kfree(data);
91 
92 	return IRQ_HANDLED;
93 }
94 
adis16260_unconfigure_ring(struct iio_dev * indio_dev)95 void adis16260_unconfigure_ring(struct iio_dev *indio_dev)
96 {
97 	iio_dealloc_pollfunc(indio_dev->pollfunc);
98 	iio_sw_rb_free(indio_dev->buffer);
99 }
100 
101 static const struct iio_buffer_setup_ops adis16260_ring_setup_ops = {
102 	.preenable = &iio_sw_buffer_preenable,
103 	.postenable = &iio_triggered_buffer_postenable,
104 	.predisable = &iio_triggered_buffer_predisable,
105 };
106 
adis16260_configure_ring(struct iio_dev * indio_dev)107 int adis16260_configure_ring(struct iio_dev *indio_dev)
108 {
109 	int ret = 0;
110 	struct iio_buffer *ring;
111 
112 	ring = iio_sw_rb_allocate(indio_dev);
113 	if (!ring) {
114 		ret = -ENOMEM;
115 		return ret;
116 	}
117 	indio_dev->buffer = ring;
118 	/* Effectively select the ring buffer implementation */
119 	ring->access = &ring_sw_access_funcs;
120 	ring->scan_timestamp = true;
121 	indio_dev->setup_ops = &adis16260_ring_setup_ops;
122 
123 	indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
124 						 &adis16260_trigger_handler,
125 						 IRQF_ONESHOT,
126 						 indio_dev,
127 						 "adis16260_consumer%d",
128 						 indio_dev->id);
129 	if (indio_dev->pollfunc == NULL) {
130 		ret = -ENOMEM;
131 		goto error_iio_sw_rb_free;
132 	}
133 
134 	indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
135 	return 0;
136 
137 error_iio_sw_rb_free:
138 	iio_sw_rb_free(indio_dev->buffer);
139 	return ret;
140 }
141