LXR linux/drivers/staging/iio/accel/adis16203

   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 <linux/iio/iio.h>
   9#include "../ring_sw.h"
  10#include <linux/iio/trigger_consumer.h>
  11#include "adis16203.h"
  12
  13/**
  14 * adis16203_read_ring_data() read data registers which will be placed into ring
  15 * @indio_dev: the IIO device
  16 * @rx: somewhere to pass back the value read
  17 **/
  18static int adis16203_read_ring_data(struct iio_dev *indio_dev, u8 *rx)
  19{
  20        struct spi_message msg;
  21        struct adis16203_state *st = iio_priv(indio_dev);
  22        struct spi_transfer xfers[ADIS16203_OUTPUTS + 1];
  23        int ret;
  24        int i;
  25
  26        mutex_lock(&st->buf_lock);
  27
  28        spi_message_init(&msg);
  29
  30        memset(xfers, 0, sizeof(xfers));
  31        for (i = 0; i <= ADIS16203_OUTPUTS; i++) {
  32                xfers[i].bits_per_word = 8;
  33                xfers[i].cs_change = 1;
  34                xfers[i].len = 2;
  35                xfers[i].delay_usecs = 20;
  36                xfers[i].tx_buf = st->tx + 2 * i;
  37                if (i < 1) /* SUPPLY_OUT: 0x02, AUX_ADC: 0x08 */
  38                        st->tx[2 * i] = ADIS16203_READ_REG(ADIS16203_SUPPLY_OUT + 2 * i);
  39                else
  40                        st->tx[2 * i] = ADIS16203_READ_REG(ADIS16203_SUPPLY_OUT + 2 * i + 6);
  41                st->tx[2 * i + 1] = 0;
  42                if (i >= 1)
  43                        xfers[i].rx_buf = rx + 2 * (i - 1);
  44                spi_message_add_tail(&xfers[i], &msg);
  45        }
  46
  47        ret = spi_sync(st->us, &msg);
  48        if (ret)
  49                dev_err(&st->us->dev, "problem when burst reading");
  50
  51        mutex_unlock(&st->buf_lock);
  52
  53        return ret;
  54}
  55
  56/* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
  57 * specific to be rolled into the core.
  58 */
  59static irqreturn_t adis16203_trigger_handler(int irq, void *p)
  60{
  61        struct iio_poll_func *pf = p;
  62        struct iio_dev *indio_dev = pf->indio_dev;
  63        struct adis16203_state *st = iio_priv(indio_dev);
  64        struct iio_buffer *ring = indio_dev->buffer;
  65
  66        int i = 0;
  67        s16 *data;
  68
  69        data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
  70        if (data == NULL) {
  71                dev_err(&st->us->dev, "memory alloc failed in ring bh");
  72                goto done;
  73        }
  74
  75        if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength) &&
  76            adis16203_read_ring_data(indio_dev, st->rx) >= 0)
  77                for (; i < bitmap_weight(indio_dev->active_scan_mask,
  78                                         indio_dev->masklength); i++)
  79                        data[i] = be16_to_cpup((__be16 *)&(st->rx[i*2]));
  80
  81        /* Guaranteed to be aligned with 8 byte boundary */
  82        if (indio_dev->scan_timestamp)
  83                *((s64 *)(data + ((i + 3)/4)*4)) = pf->timestamp;
  84
  85        ring->access->store_to(ring,
  86                              (u8 *)data,
  87                              pf->timestamp);
  88
  89        kfree(data);
  90done:
  91        iio_trigger_notify_done(indio_dev->trig);
  92
  93        return IRQ_HANDLED;
  94}
  95
  96void adis16203_unconfigure_ring(struct iio_dev *indio_dev)
  97{
  98        iio_dealloc_pollfunc(indio_dev->pollfunc);
  99        iio_sw_rb_free(indio_dev->buffer);
 100}
 101
 102static const struct iio_buffer_setup_ops adis16203_ring_setup_ops = {
 103        .preenable = &iio_sw_buffer_preenable,
 104        .postenable = &iio_triggered_buffer_postenable,
 105        .predisable = &iio_triggered_buffer_predisable,
 106};
 107
 108int adis16203_configure_ring(struct iio_dev *indio_dev)
 109{
 110        int ret = 0;
 111        struct iio_buffer *ring;
 112
 113        ring = iio_sw_rb_allocate(indio_dev);
 114        if (!ring) {
 115                ret = -ENOMEM;
 116                return ret;
 117        }
 118        indio_dev->buffer = ring;
 119        ring->scan_timestamp = true;
 120        indio_dev->setup_ops = &adis16203_ring_setup_ops;
 121
 122        indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
 123                                                 &adis16203_trigger_handler,
 124                                                 IRQF_ONESHOT,
 125                                                 indio_dev,
 126                                                 "adis16203_consumer%d",
 127                                                 indio_dev->id);
 128        if (indio_dev->pollfunc == NULL) {
 129                ret = -ENOMEM;
 130                goto error_iio_sw_rb_free;
 131        }
 132
 133        indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
 134        return 0;
 135
 136error_iio_sw_rb_free:
 137        iio_sw_rb_free(indio_dev->buffer);
 138        return ret;
 139}
 140