drivers/staging/iio/accel/adis16209_ring.c

   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 "adis16209.h"
  19
  20 static IIO_SCAN_EL_C(in_supply, ADIS16209_SCAN_SUPPLY,
  21                      ADIS16209_SUPPLY_OUT, NULL);
  22 static IIO_CONST_ATTR_SCAN_EL_TYPE(in_supply, u, 14, 16)
  23 static IIO_SCAN_EL_C(accel_x, ADIS16209_SCAN_ACC_X, ADIS16209_XACCL_OUT, NULL);
  24 static IIO_SCAN_EL_C(accel_y, ADIS16209_SCAN_ACC_Y, ADIS16209_YACCL_OUT, NULL);
  25 static IIO_CONST_ATTR_SCAN_EL_TYPE(accel, s, 14, 16);
  26 static IIO_SCAN_EL_C(in0, ADIS16209_SCAN_AUX_ADC, ADIS16209_AUX_ADC, NULL);
  27 static IIO_CONST_ATTR_SCAN_EL_TYPE(in0, u, 12, 16);
  28 static IIO_SCAN_EL_C(temp, ADIS16209_SCAN_TEMP, ADIS16209_TEMP_OUT, NULL);
  29 static IIO_CONST_ATTR_SCAN_EL_TYPE(temp, u, 12, 16);
  30 static IIO_SCAN_EL_C(incli_x, ADIS16209_SCAN_INCLI_X,
  31                      ADIS16209_XINCL_OUT, NULL);
  32 static IIO_SCAN_EL_C(incli_y, ADIS16209_SCAN_INCLI_Y,
  33                      ADIS16209_YINCL_OUT, NULL);
  34 static IIO_CONST_ATTR_SCAN_EL_TYPE(incli, s, 14, 16);
  35 static IIO_SCAN_EL_C(rot, ADIS16209_SCAN_ROT, ADIS16209_ROT_OUT, NULL);
  36 static IIO_CONST_ATTR_SCAN_EL_TYPE(rot, s, 14, 16);
  37 static IIO_SCAN_EL_TIMESTAMP(8);
  38 static IIO_CONST_ATTR_SCAN_EL_TYPE(timestamp, s, 64, 64);
  39
  40 static struct attribute *adis16209_scan_el_attrs[] = {
  41         &iio_scan_el_in_supply.dev_attr.attr,
  42         &iio_const_attr_in_supply_type.dev_attr.attr,
  43         &iio_scan_el_accel_x.dev_attr.attr,
  44         &iio_scan_el_accel_y.dev_attr.attr,
  45         &iio_const_attr_accel_type.dev_attr.attr,
  46         &iio_scan_el_in0.dev_attr.attr,
  47         &iio_const_attr_in0_type.dev_attr.attr,
  48         &iio_scan_el_temp.dev_attr.attr,
  49         &iio_const_attr_temp_type.dev_attr.attr,
  50         &iio_scan_el_incli_x.dev_attr.attr,
  51         &iio_scan_el_incli_y.dev_attr.attr,
  52         &iio_const_attr_incli_type.dev_attr.attr,
  53         &iio_scan_el_rot.dev_attr.attr,
  54         &iio_const_attr_rot_type.dev_attr.attr,
  55         &iio_scan_el_timestamp.dev_attr.attr,
  56         &iio_const_attr_timestamp_type.dev_attr.attr,
  57         NULL,
  58 };
  59
  60 static struct attribute_group adis16209_scan_el_group = {
  61         .attrs = adis16209_scan_el_attrs,
  62         .name = "scan_elements",
  63 };
  64
  65 /**
  66  * adis16209_poll_func_th() top half interrupt handler called by trigger
  67  * @private_data:       iio_dev
  68  **/
  69 static void adis16209_poll_func_th(struct iio_dev *indio_dev, s64 time)
  70 {
  71         struct adis16209_state *st = iio_dev_get_devdata(indio_dev);
  72         st->last_timestamp = time;
  73         schedule_work(&st->work_trigger_to_ring);
  74 }
  75
  76 /**
  77  * adis16209_read_ring_data() read data registers which will be placed into ring
  78  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  79  * @rx: somewhere to pass back the value read
  80  **/
  81 static int adis16209_read_ring_data(struct device *dev, u8 *rx)
  82 {
  83         struct spi_message msg;
  84         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  85         struct adis16209_state *st = iio_dev_get_devdata(indio_dev);
  86         struct spi_transfer xfers[ADIS16209_OUTPUTS + 1];
  87         int ret;
  88         int i;
  89
  90         mutex_lock(&st->buf_lock);
  91
  92         spi_message_init(&msg);
  93
  94         memset(xfers, 0, sizeof(xfers));
  95         for (i = 0; i <= ADIS16209_OUTPUTS; i++) {
  96                 xfers[i].bits_per_word = 8;
  97                 xfers[i].cs_change = 1;
  98                 xfers[i].len = 2;
  99                 xfers[i].delay_usecs = 20;
 100                 xfers[i].tx_buf = st->tx + 2 * i;
 101                 st->tx[2 * i]
 102                         = ADIS16209_READ_REG(ADIS16209_SUPPLY_OUT + 2 * i);
 103                 st->tx[2 * i + 1] = 0;
 104                 if (i >= 1)
 105                         xfers[i].rx_buf = rx + 2 * (i - 1);
 106                 spi_message_add_tail(&xfers[i], &msg);
 107         }
 108
 109         ret = spi_sync(st->us, &msg);
 110         if (ret)
 111                 dev_err(&st->us->dev, "problem when burst reading");
 112
 113         mutex_unlock(&st->buf_lock);
 114
 115         return ret;
 116 }
 117
 118 /* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
 119  * specific to be rolled into the core.
 120  */
 121 static void adis16209_trigger_bh_to_ring(struct work_struct *work_s)
 122 {
 123         struct adis16209_state *st
 124                 = container_of(work_s, struct adis16209_state,
 125                                work_trigger_to_ring);
 126         struct iio_ring_buffer *ring = st->indio_dev->ring;
 127
 128         int i = 0;
 129         s16 *data;
 130         size_t datasize = ring->access.get_bytes_per_datum(ring);
 131
 132         data = kmalloc(datasize , GFP_KERNEL);
 133         if (data == NULL) {
 134                 dev_err(&st->us->dev, "memory alloc failed in ring bh");
 135                 return;
 136         }
 137
 138         if (ring->scan_count)
 139                 if (adis16209_read_ring_data(&st->indio_dev->dev, st->rx) >= 0)
 140                         for (; i < ring->scan_count; i++)
 141                                 data[i] = be16_to_cpup(
 142                                         (__be16 *)&(st->rx[i*2]));
 143
 144         /* Guaranteed to be aligned with 8 byte boundary */
 145         if (ring->scan_timestamp)
 146                 *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp;
 147
 148         ring->access.store_to(ring,
 149                               (u8 *)data,
 150                               st->last_timestamp);
 151
 152         iio_trigger_notify_done(st->indio_dev->trig);
 153         kfree(data);
 154
 155         return;
 156 }
 157
 158 void adis16209_unconfigure_ring(struct iio_dev *indio_dev)
 159 {
 160         kfree(indio_dev->pollfunc);
 161         iio_sw_rb_free(indio_dev->ring);
 162 }
 163
 164 int adis16209_configure_ring(struct iio_dev *indio_dev)
 165 {
 166         int ret = 0;
 167         struct adis16209_state *st = indio_dev->dev_data;
 168         struct iio_ring_buffer *ring;
 169         INIT_WORK(&st->work_trigger_to_ring, adis16209_trigger_bh_to_ring);
 170
 171         ring = iio_sw_rb_allocate(indio_dev);
 172         if (!ring) {
 173                 ret = -ENOMEM;
 174                 return ret;
 175         }
 176         indio_dev->ring = ring;
 177         /* Effectively select the ring buffer implementation */
 178         iio_ring_sw_register_funcs(&ring->access);
 179         ring->bpe = 2;
 180         ring->scan_el_attrs = &adis16209_scan_el_group;
 181         ring->scan_timestamp = true;
 182         ring->preenable = &iio_sw_ring_preenable;
 183         ring->postenable = &iio_triggered_ring_postenable;
 184         ring->predisable = &iio_triggered_ring_predisable;
 185         ring->owner = THIS_MODULE;
 186
 187         /* Set default scan mode */
 188         iio_scan_mask_set(ring, iio_scan_el_in_supply.number);
 189         iio_scan_mask_set(ring, iio_scan_el_rot.number);
 190         iio_scan_mask_set(ring, iio_scan_el_accel_x.number);
 191         iio_scan_mask_set(ring, iio_scan_el_accel_y.number);
 192         iio_scan_mask_set(ring, iio_scan_el_temp.number);
 193         iio_scan_mask_set(ring, iio_scan_el_in0.number);
 194         iio_scan_mask_set(ring, iio_scan_el_incli_x.number);
 195         iio_scan_mask_set(ring, iio_scan_el_incli_y.number);
 196
 197         ret = iio_alloc_pollfunc(indio_dev, NULL, &adis16209_poll_func_th);
 198         if (ret)
 199                 goto error_iio_sw_rb_free;
 200
 201         indio_dev->modes |= INDIO_RING_TRIGGERED;
 202         return 0;
 203
 204 error_iio_sw_rb_free:
 205         iio_sw_rb_free(indio_dev->ring);
 206         return ret;
 207 }