drivers/staging/iio/imu/adis16300_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/accel.h"
  17 #include "../trigger.h"
  18 #include "adis16300.h"
  19
  20 static IIO_SCAN_EL_C(in0_supply, ADIS16300_SCAN_SUPPLY,
  21                      ADIS16300_SUPPLY_OUT, NULL);
  22 static IIO_CONST_ATTR_SCAN_EL_TYPE(in0_supply, u, 12, 16);
  23 static IIO_SCAN_EL_C(gyro_x, ADIS16300_SCAN_GYRO_X, ADIS16300_XGYRO_OUT, NULL);
  24 static IIO_CONST_ATTR_SCAN_EL_TYPE(gyro, s, 14, 16);
  25
  26 static IIO_SCAN_EL_C(accel_x, ADIS16300_SCAN_ACC_X, ADIS16300_XACCL_OUT, NULL);
  27 static IIO_SCAN_EL_C(accel_y, ADIS16300_SCAN_ACC_Y, ADIS16300_YACCL_OUT, NULL);
  28 static IIO_SCAN_EL_C(accel_z, ADIS16300_SCAN_ACC_Z, ADIS16300_ZACCL_OUT, NULL);
  29 static IIO_CONST_ATTR_SCAN_EL_TYPE(accel, s, 14, 16);
  30
  31 static IIO_SCAN_EL_C(temp, ADIS16300_SCAN_TEMP, ADIS16300_TEMP_OUT, NULL);
  32 static IIO_CONST_ATTR_SCAN_EL_TYPE(temp, s, 12, 16);
  33
  34 static IIO_SCAN_EL_C(in1, ADIS16300_SCAN_ADC_0, ADIS16300_AUX_ADC, NULL);
  35 static IIO_CONST_ATTR_SCAN_EL_TYPE(in1, u, 12, 16);
  36
  37 static IIO_SCAN_EL_C(incli_x, ADIS16300_SCAN_INCLI_X,
  38                      ADIS16300_XINCLI_OUT, NULL);
  39 static IIO_SCAN_EL_C(incli_y, ADIS16300_SCAN_INCLI_Y,
  40                      ADIS16300_YINCLI_OUT, NULL);
  41 static IIO_CONST_ATTR_SCAN_EL_TYPE(incli, s, 13, 16);
  42
  43 static IIO_SCAN_EL_TIMESTAMP(9);
  44 static IIO_CONST_ATTR_SCAN_EL_TYPE(timestamp, s, 64, 64);
  45
  46 static struct attribute *adis16300_scan_el_attrs[] = {
  47         &iio_scan_el_in0_supply.dev_attr.attr,
  48         &iio_const_attr_in0_supply_index.dev_attr.attr,
  49         &iio_const_attr_in0_supply_type.dev_attr.attr,
  50         &iio_scan_el_gyro_x.dev_attr.attr,
  51         &iio_const_attr_gyro_x_index.dev_attr.attr,
  52         &iio_const_attr_gyro_type.dev_attr.attr,
  53         &iio_scan_el_temp.dev_attr.attr,
  54         &iio_const_attr_temp_index.dev_attr.attr,
  55         &iio_const_attr_temp_type.dev_attr.attr,
  56         &iio_scan_el_accel_x.dev_attr.attr,
  57         &iio_const_attr_accel_x_index.dev_attr.attr,
  58         &iio_scan_el_accel_y.dev_attr.attr,
  59         &iio_const_attr_accel_y_index.dev_attr.attr,
  60         &iio_scan_el_accel_z.dev_attr.attr,
  61         &iio_const_attr_accel_z_index.dev_attr.attr,
  62         &iio_const_attr_accel_type.dev_attr.attr,
  63         &iio_scan_el_incli_x.dev_attr.attr,
  64         &iio_const_attr_incli_x_index.dev_attr.attr,
  65         &iio_scan_el_incli_y.dev_attr.attr,
  66         &iio_const_attr_incli_y_index.dev_attr.attr,
  67         &iio_const_attr_incli_type.dev_attr.attr,
  68         &iio_scan_el_in1.dev_attr.attr,
  69         &iio_const_attr_in1_index.dev_attr.attr,
  70         &iio_const_attr_in1_type.dev_attr.attr,
  71         &iio_scan_el_timestamp.dev_attr.attr,
  72         &iio_const_attr_timestamp_index.dev_attr.attr,
  73         &iio_const_attr_timestamp_type.dev_attr.attr,
  74         NULL,
  75 };
  76
  77 static struct attribute_group adis16300_scan_el_group = {
  78         .attrs = adis16300_scan_el_attrs,
  79         .name = "scan_elements",
  80 };
  81
  82 /**
  83  * adis16300_poll_func_th() top half interrupt handler called by trigger
  84  * @private_data:       iio_dev
  85  **/
  86 static void adis16300_poll_func_th(struct iio_dev *indio_dev, s64 time)
  87 {
  88         struct adis16300_state *st = iio_dev_get_devdata(indio_dev);
  89         st->last_timestamp = time;
  90         schedule_work(&st->work_trigger_to_ring);
  91         /* Indicate that this interrupt is being handled */
  92
  93         /* Technically this is trigger related, but without this
  94          * handler running there is currently no way for the interrupt
  95          * to clear.
  96          */
  97 }
  98
  99 /**
 100  * adis16300_spi_read_burst() - read all data registers
 101  * @dev: device associated with child of actual device (iio_dev or iio_trig)
 102  * @rx: somewhere to pass back the value read (min size is 24 bytes)
 103  **/
 104 static int adis16300_spi_read_burst(struct device *dev, u8 *rx)
 105 {
 106         struct spi_message msg;
 107         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 108         struct adis16300_state *st = iio_dev_get_devdata(indio_dev);
 109         u32 old_speed_hz = st->us->max_speed_hz;
 110         int ret;
 111
 112         struct spi_transfer xfers[] = {
 113                 {
 114                         .tx_buf = st->tx,
 115                         .bits_per_word = 8,
 116                         .len = 2,
 117                         .cs_change = 0,
 118                 }, {
 119                         .rx_buf = rx,
 120                         .bits_per_word = 8,
 121                         .len = 18,
 122                         .cs_change = 0,
 123                 },
 124         };
 125
 126         mutex_lock(&st->buf_lock);
 127         st->tx[0] = ADIS16300_READ_REG(ADIS16300_GLOB_CMD);
 128         st->tx[1] = 0;
 129
 130         spi_message_init(&msg);
 131         spi_message_add_tail(&xfers[0], &msg);
 132         spi_message_add_tail(&xfers[1], &msg);
 133
 134         st->us->max_speed_hz = ADIS16300_SPI_BURST;
 135         spi_setup(st->us);
 136
 137         ret = spi_sync(st->us, &msg);
 138         if (ret)
 139                 dev_err(&st->us->dev, "problem when burst reading");
 140
 141         st->us->max_speed_hz = old_speed_hz;
 142         spi_setup(st->us);
 143         mutex_unlock(&st->buf_lock);
 144         return ret;
 145 }
 146
 147 /* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
 148  * specific to be rolled into the core.
 149  */
 150 static void adis16300_trigger_bh_to_ring(struct work_struct *work_s)
 151 {
 152         struct adis16300_state *st
 153                 = container_of(work_s, struct adis16300_state,
 154                                work_trigger_to_ring);
 155         struct iio_ring_buffer *ring = st->indio_dev->ring;
 156
 157         int i = 0;
 158         s16 *data;
 159         size_t datasize = ring->access.get_bytes_per_datum(ring);
 160
 161         data = kmalloc(datasize , GFP_KERNEL);
 162         if (data == NULL) {
 163                 dev_err(&st->us->dev, "memory alloc failed in ring bh");
 164                 return;
 165         }
 166
 167         if (ring->scan_count)
 168                 if (adis16300_spi_read_burst(&st->indio_dev->dev, st->rx) >= 0)
 169                         for (; i < ring->scan_count; i++)
 170                                 data[i] = be16_to_cpup(
 171                                         (__be16 *)&(st->rx[i*2]));
 172
 173         /* Guaranteed to be aligned with 8 byte boundary */
 174         if (ring->scan_timestamp)
 175                 *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp;
 176
 177         ring->access.store_to(ring,
 178                         (u8 *)data,
 179                         st->last_timestamp);
 180
 181         iio_trigger_notify_done(st->indio_dev->trig);
 182         kfree(data);
 183
 184         return;
 185 }
 186
 187 void adis16300_unconfigure_ring(struct iio_dev *indio_dev)
 188 {
 189         kfree(indio_dev->pollfunc);
 190         iio_sw_rb_free(indio_dev->ring);
 191 }
 192
 193 int adis16300_configure_ring(struct iio_dev *indio_dev)
 194 {
 195         int ret = 0;
 196         struct adis16300_state *st = indio_dev->dev_data;
 197         struct iio_ring_buffer *ring;
 198         INIT_WORK(&st->work_trigger_to_ring, adis16300_trigger_bh_to_ring);
 199
 200         ring = iio_sw_rb_allocate(indio_dev);
 201         if (!ring) {
 202                 ret = -ENOMEM;
 203                 return ret;
 204         }
 205         indio_dev->ring = ring;
 206         /* Effectively select the ring buffer implementation */
 207         iio_ring_sw_register_funcs(&ring->access);
 208         ring->bpe = 2;
 209         ring->scan_el_attrs = &adis16300_scan_el_group;
 210         ring->scan_timestamp = true;
 211         ring->preenable = &iio_sw_ring_preenable;
 212         ring->postenable = &iio_triggered_ring_postenable;
 213         ring->predisable = &iio_triggered_ring_predisable;
 214         ring->owner = THIS_MODULE;
 215
 216         /* Set default scan mode */
 217         iio_scan_mask_set(ring, iio_scan_el_in0_supply.number);
 218         iio_scan_mask_set(ring, iio_scan_el_gyro_x.number);
 219         iio_scan_mask_set(ring, iio_scan_el_accel_x.number);
 220         iio_scan_mask_set(ring, iio_scan_el_accel_y.number);
 221         iio_scan_mask_set(ring, iio_scan_el_accel_z.number);
 222         iio_scan_mask_set(ring, iio_scan_el_temp.number);
 223         iio_scan_mask_set(ring, iio_scan_el_in1.number);
 224         iio_scan_mask_set(ring, iio_scan_el_incli_x.number);
 225         iio_scan_mask_set(ring, iio_scan_el_incli_y.number);
 226
 227         ret = iio_alloc_pollfunc(indio_dev, NULL, &adis16300_poll_func_th);
 228         if (ret)
 229                 goto error_iio_sw_rb_free;
 230
 231         indio_dev->modes |= INDIO_RING_TRIGGERED;
 232         return 0;
 233
 234 error_iio_sw_rb_free:
 235         iio_sw_rb_free(indio_dev->ring);
 236         return ret;
 237 }
 238