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, IIO_UNSIGNED(14),
  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, IIO_SIGNED(14),
  24                      ADIS16209_XACCL_OUT, NULL);
  25 static IIO_SCAN_EL_C(accel_y, ADIS16209_SCAN_ACC_Y, IIO_SIGNED(14),
  26                      ADIS16209_YACCL_OUT, NULL);
  27 static IIO_CONST_ATTR_SCAN_EL_TYPE(accel, s, 14, 16);
  28 static IIO_SCAN_EL_C(in0, ADIS16209_SCAN_AUX_ADC, IIO_UNSIGNED(12),
  29                      ADIS16209_AUX_ADC, NULL);
  30 static IIO_CONST_ATTR_SCAN_EL_TYPE(in0, u, 12, 16);
  31 static IIO_SCAN_EL_C(temp, ADIS16209_SCAN_TEMP, IIO_UNSIGNED(12),
  32                      ADIS16209_TEMP_OUT, NULL);
  33 static IIO_CONST_ATTR_SCAN_EL_TYPE(temp, u, 12, 16);
  34 static IIO_SCAN_EL_C(incli_x, ADIS16209_SCAN_INCLI_X, IIO_SIGNED(14),
  35                      ADIS16209_XINCL_OUT, NULL);
  36 static IIO_SCAN_EL_C(incli_y, ADIS16209_SCAN_INCLI_Y, IIO_SIGNED(14),
  37                      ADIS16209_YINCL_OUT, NULL);
  38 static IIO_CONST_ATTR_SCAN_EL_TYPE(incli, s, 14, 16);
  39 static IIO_SCAN_EL_C(rot, ADIS16209_SCAN_ROT, IIO_SIGNED(14),
  40                      ADIS16209_ROT_OUT, NULL);
  41 static IIO_CONST_ATTR_SCAN_EL_TYPE(rot, s, 14, 16);
  42 static IIO_SCAN_EL_TIMESTAMP(8);
  43 static IIO_CONST_ATTR_SCAN_EL_TYPE(timestamp, s, 64, 64);
  44
  45 static struct attribute *adis16209_scan_el_attrs[] = {
  46         &iio_scan_el_in_supply.dev_attr.attr,
  47         &iio_const_attr_in_supply_type.dev_attr.attr,
  48         &iio_scan_el_accel_x.dev_attr.attr,
  49         &iio_scan_el_accel_y.dev_attr.attr,
  50         &iio_const_attr_accel_type.dev_attr.attr,
  51         &iio_scan_el_in0.dev_attr.attr,
  52         &iio_const_attr_in0_type.dev_attr.attr,
  53         &iio_scan_el_temp.dev_attr.attr,
  54         &iio_const_attr_temp_type.dev_attr.attr,
  55         &iio_scan_el_incli_x.dev_attr.attr,
  56         &iio_scan_el_incli_y.dev_attr.attr,
  57         &iio_const_attr_incli_type.dev_attr.attr,
  58         &iio_scan_el_rot.dev_attr.attr,
  59         &iio_const_attr_rot_type.dev_attr.attr,
  60         &iio_scan_el_timestamp.dev_attr.attr,
  61         &iio_const_attr_timestamp_type.dev_attr.attr,
  62         NULL,
  63 };
  64
  65 static struct attribute_group adis16209_scan_el_group = {
  66         .attrs = adis16209_scan_el_attrs,
  67         .name = "scan_elements",
  68 };
  69
  70 /**
  71  * adis16209_poll_func_th() top half interrupt handler called by trigger
  72  * @private_data:       iio_dev
  73  **/
  74 static void adis16209_poll_func_th(struct iio_dev *indio_dev, s64 time)
  75 {
  76         struct adis16209_state *st = iio_dev_get_devdata(indio_dev);
  77         st->last_timestamp = time;
  78         schedule_work(&st->work_trigger_to_ring);
  79 }
  80
  81 /**
  82  * adis16209_read_ring_data() read data registers which will be placed into ring
  83  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  84  * @rx: somewhere to pass back the value read
  85  **/
  86 static int adis16209_read_ring_data(struct device *dev, u8 *rx)
  87 {
  88         struct spi_message msg;
  89         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  90         struct adis16209_state *st = iio_dev_get_devdata(indio_dev);
  91         struct spi_transfer xfers[ADIS16209_OUTPUTS + 1];
  92         int ret;
  93         int i;
  94
  95         mutex_lock(&st->buf_lock);
  96
  97         spi_message_init(&msg);
  98
  99         memset(xfers, 0, sizeof(xfers));
 100         for (i = 0; i <= ADIS16209_OUTPUTS; i++) {
 101                 xfers[i].bits_per_word = 8;
 102                 xfers[i].cs_change = 1;
 103                 xfers[i].len = 2;
 104                 xfers[i].delay_usecs = 20;
 105                 xfers[i].tx_buf = st->tx + 2 * i;
 106                 st->tx[2 * i]
 107                         = ADIS16209_READ_REG(ADIS16209_SUPPLY_OUT + 2 * i);
 108                 st->tx[2 * i + 1] = 0;
 109                 if (i >= 1)
 110                         xfers[i].rx_buf = rx + 2 * (i - 1);
 111                 spi_message_add_tail(&xfers[i], &msg);
 112         }
 113
 114         ret = spi_sync(st->us, &msg);
 115         if (ret)
 116                 dev_err(&st->us->dev, "problem when burst reading");
 117
 118         mutex_unlock(&st->buf_lock);
 119
 120         return ret;
 121 }
 122
 123 /* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
 124  * specific to be rolled into the core.
 125  */
 126 static void adis16209_trigger_bh_to_ring(struct work_struct *work_s)
 127 {
 128         struct adis16209_state *st
 129                 = container_of(work_s, struct adis16209_state,
 130                                work_trigger_to_ring);
 131         struct iio_ring_buffer *ring = st->indio_dev->ring;
 132
 133         int i = 0;
 134         s16 *data;
 135         size_t datasize = ring->access.get_bytes_per_datum(ring);
 136
 137         data = kmalloc(datasize , GFP_KERNEL);
 138         if (data == NULL) {
 139                 dev_err(&st->us->dev, "memory alloc failed in ring bh");
 140                 return;
 141         }
 142
 143         if (ring->scan_count)
 144                 if (adis16209_read_ring_data(&st->indio_dev->dev, st->rx) >= 0)
 145                         for (; i < ring->scan_count; i++)
 146                                 data[i] = be16_to_cpup(
 147                                         (__be16 *)&(st->rx[i*2]));
 148
 149         /* Guaranteed to be aligned with 8 byte boundary */
 150         if (ring->scan_timestamp)
 151                 *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp;
 152
 153         ring->access.store_to(ring,
 154                               (u8 *)data,
 155                               st->last_timestamp);
 156
 157         iio_trigger_notify_done(st->indio_dev->trig);
 158         kfree(data);
 159
 160         return;
 161 }
 162
 163 void adis16209_unconfigure_ring(struct iio_dev *indio_dev)
 164 {
 165         kfree(indio_dev->pollfunc);
 166         iio_sw_rb_free(indio_dev->ring);
 167 }
 168
 169 int adis16209_configure_ring(struct iio_dev *indio_dev)
 170 {
 171         int ret = 0;
 172         struct adis16209_state *st = indio_dev->dev_data;
 173         struct iio_ring_buffer *ring;
 174         INIT_WORK(&st->work_trigger_to_ring, adis16209_trigger_bh_to_ring);
 175
 176         ring = iio_sw_rb_allocate(indio_dev);
 177         if (!ring) {
 178                 ret = -ENOMEM;
 179                 return ret;
 180         }
 181         indio_dev->ring = ring;
 182         /* Effectively select the ring buffer implementation */
 183         iio_ring_sw_register_funcs(&ring->access);
 184         ring->bpe = 2;
 185         ring->scan_el_attrs = &adis16209_scan_el_group;
 186         ring->scan_timestamp = true;
 187         ring->preenable = &iio_sw_ring_preenable;
 188         ring->postenable = &iio_triggered_ring_postenable;
 189         ring->predisable = &iio_triggered_ring_predisable;
 190         ring->owner = THIS_MODULE;
 191
 192         /* Set default scan mode */
 193         iio_scan_mask_set(ring, iio_scan_el_in_supply.number);
 194         iio_scan_mask_set(ring, iio_scan_el_rot.number);
 195         iio_scan_mask_set(ring, iio_scan_el_accel_x.number);
 196         iio_scan_mask_set(ring, iio_scan_el_accel_y.number);
 197         iio_scan_mask_set(ring, iio_scan_el_temp.number);
 198         iio_scan_mask_set(ring, iio_scan_el_in0.number);
 199         iio_scan_mask_set(ring, iio_scan_el_incli_x.number);
 200         iio_scan_mask_set(ring, iio_scan_el_incli_y.number);
 201
 202         ret = iio_alloc_pollfunc(indio_dev, NULL, &adis16209_poll_func_th);
 203         if (ret)
 204                 goto error_iio_sw_rb_free;
 205
 206         indio_dev->modes |= INDIO_RING_TRIGGERED;
 207         return 0;
 208
 209 error_iio_sw_rb_free:
 210         iio_sw_rb_free(indio_dev->ring);
 211         return ret;
 212 }