Loading...
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 | /*
* Copyright (C) 2010 Michael Hennerich, Analog Devices Inc.
* Copyright (C) 2008-2010 Jonathan Cameron
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* ad799x_ring.c
*/
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/sysfs.h>
#include <linux/list.h>
#include <linux/i2c.h>
#include <linux/bitops.h>
#include "../iio.h"
#include "../ring_generic.h"
#include "../ring_sw.h"
#include "../trigger.h"
#include "../sysfs.h"
#include "ad799x.h"
int ad799x_single_channel_from_ring(struct ad799x_state *st, long mask)
{
struct iio_ring_buffer *ring = iio_priv_to_dev(st)->ring;
int count = 0, ret;
u16 *ring_data;
if (!(ring->scan_mask & mask)) {
ret = -EBUSY;
goto error_ret;
}
ring_data = kmalloc(ring->access->get_bytes_per_datum(ring),
GFP_KERNEL);
if (ring_data == NULL) {
ret = -ENOMEM;
goto error_ret;
}
ret = ring->access->read_last(ring, (u8 *) ring_data);
if (ret)
goto error_free_ring_data;
/* Need a count of channels prior to this one */
mask >>= 1;
while (mask) {
if (mask & ring->scan_mask)
count++;
mask >>= 1;
}
ret = be16_to_cpu(ring_data[count]);
error_free_ring_data:
kfree(ring_data);
error_ret:
return ret;
}
/**
* ad799x_ring_preenable() setup the parameters of the ring before enabling
*
* The complex nature of the setting of the nuber of bytes per datum is due
* to this driver currently ensuring that the timestamp is stored at an 8
* byte boundary.
**/
static int ad799x_ring_preenable(struct iio_dev *indio_dev)
{
struct iio_ring_buffer *ring = indio_dev->ring;
struct ad799x_state *st = iio_dev_get_devdata(indio_dev);
/*
* Need to figure out the current mode based upon the requested
* scan mask in iio_dev
*/
if (st->id == ad7997 || st->id == ad7998)
ad7997_8_set_scan_mode(st, ring->scan_mask);
st->d_size = ring->scan_count * 2;
if (ring->scan_timestamp) {
st->d_size += sizeof(s64);
if (st->d_size % sizeof(s64))
st->d_size += sizeof(s64) - (st->d_size % sizeof(s64));
}
if (indio_dev->ring->access->set_bytes_per_datum)
indio_dev->ring->access->set_bytes_per_datum(indio_dev->ring,
st->d_size);
return 0;
}
/**
* ad799x_trigger_handler() bh of trigger launched polling to ring buffer
*
* Currently there is no option in this driver to disable the saving of
* timestamps within the ring.
**/
static irqreturn_t ad799x_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->private_data;
struct ad799x_state *st = iio_dev_get_devdata(indio_dev);
struct iio_ring_buffer *ring = indio_dev->ring;
s64 time_ns;
__u8 *rxbuf;
int b_sent;
u8 cmd;
rxbuf = kmalloc(st->d_size, GFP_KERNEL);
if (rxbuf == NULL)
goto out;
switch (st->id) {
case ad7991:
case ad7995:
case ad7999:
cmd = st->config | (ring->scan_mask << AD799X_CHANNEL_SHIFT);
break;
case ad7992:
case ad7993:
case ad7994:
cmd = (ring->scan_mask << AD799X_CHANNEL_SHIFT) |
AD7998_CONV_RES_REG;
break;
case ad7997:
case ad7998:
cmd = AD7997_8_READ_SEQUENCE | AD7998_CONV_RES_REG;
break;
default:
cmd = 0;
}
b_sent = i2c_smbus_read_i2c_block_data(st->client,
cmd, ring->scan_count * 2, rxbuf);
if (b_sent < 0)
goto done;
time_ns = iio_get_time_ns();
if (ring->scan_timestamp)
memcpy(rxbuf + st->d_size - sizeof(s64),
&time_ns, sizeof(time_ns));
ring->access->store_to(indio_dev->ring, rxbuf, time_ns);
done:
kfree(rxbuf);
if (b_sent < 0)
return b_sent;
out:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static const struct iio_ring_setup_ops ad799x_buf_setup_ops = {
.preenable = &ad799x_ring_preenable,
.postenable = &iio_triggered_ring_postenable,
.predisable = &iio_triggered_ring_predisable,
};
int ad799x_register_ring_funcs_and_init(struct iio_dev *indio_dev)
{
int ret = 0;
indio_dev->ring = iio_sw_rb_allocate(indio_dev);
if (!indio_dev->ring) {
ret = -ENOMEM;
goto error_ret;
}
/* Effectively select the ring buffer implementation */
indio_dev->ring->access = &ring_sw_access_funcs;
indio_dev->pollfunc = iio_alloc_pollfunc(NULL,
&ad799x_trigger_handler,
IRQF_ONESHOT,
indio_dev,
"%s_consumer%d",
indio_dev->name,
indio_dev->id);
if (indio_dev->pollfunc == NULL) {
ret = -ENOMEM;
goto error_deallocate_sw_rb;
}
/* Ring buffer functions - here trigger setup related */
indio_dev->ring->setup_ops = &ad799x_buf_setup_ops;
indio_dev->ring->scan_timestamp = true;
/* Flag that polled ring buffering is possible */
indio_dev->modes |= INDIO_RING_TRIGGERED;
return 0;
error_deallocate_sw_rb:
iio_sw_rb_free(indio_dev->ring);
error_ret:
return ret;
}
void ad799x_ring_cleanup(struct iio_dev *indio_dev)
{
/* ensure that the trigger has been detached */
if (indio_dev->trig) {
iio_put_trigger(indio_dev->trig);
iio_trigger_dettach_poll_func(indio_dev->trig,
indio_dev->pollfunc);
}
iio_dealloc_pollfunc(indio_dev->pollfunc);
iio_sw_rb_free(indio_dev->ring);
}
|