drivers/staging/iio/imu/adis16400_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 "adis16400.h"
  19
  20 static IIO_SCAN_EL_C(in0_supply, ADIS16400_SCAN_SUPPLY,
  21                      ADIS16400_SUPPLY_OUT, NULL);
  22 static IIO_CONST_ATTR_SCAN_EL_TYPE(in0_supply, u, 14, 16);
  23
  24 static IIO_SCAN_EL_C(gyro_x, ADIS16400_SCAN_GYRO_X, ADIS16400_XGYRO_OUT, NULL);
  25 static IIO_SCAN_EL_C(gyro_y, ADIS16400_SCAN_GYRO_Y, ADIS16400_YGYRO_OUT, NULL);
  26 static IIO_SCAN_EL_C(gyro_z, ADIS16400_SCAN_GYRO_Z, ADIS16400_ZGYRO_OUT, NULL);
  27 static IIO_CONST_ATTR_SCAN_EL_TYPE(gyro, s, 14, 16);
  28
  29 static IIO_SCAN_EL_C(accel_x, ADIS16400_SCAN_ACC_X, ADIS16400_XACCL_OUT, NULL);
  30 static IIO_SCAN_EL_C(accel_y, ADIS16400_SCAN_ACC_Y, ADIS16400_YACCL_OUT, NULL);
  31 static IIO_SCAN_EL_C(accel_z, ADIS16400_SCAN_ACC_Z, ADIS16400_ZACCL_OUT, NULL);
  32 static IIO_CONST_ATTR_SCAN_EL_TYPE(accel, s, 14, 16);
  33
  34 static IIO_SCAN_EL_C(magn_x, ADIS16400_SCAN_MAGN_X, ADIS16400_XMAGN_OUT, NULL);
  35 static IIO_SCAN_EL_C(magn_y, ADIS16400_SCAN_MAGN_Y, ADIS16400_YMAGN_OUT, NULL);
  36 static IIO_SCAN_EL_C(magn_z, ADIS16400_SCAN_MAGN_Z, ADIS16400_ZMAGN_OUT, NULL);
  37 static IIO_CONST_ATTR_SCAN_EL_TYPE(magn, s, 14, 16);
  38
  39 static IIO_SCAN_EL_C(temp, ADIS16400_SCAN_TEMP, ADIS16400_TEMP_OUT, NULL);
  40 static IIO_CONST_ATTR_SCAN_EL_TYPE(temp, s, 12, 16);
  41
  42 static IIO_SCAN_EL_C(in1, ADIS16400_SCAN_ADC_0, ADIS16400_AUX_ADC, NULL);
  43 static IIO_CONST_ATTR_SCAN_EL_TYPE(in1, u, 12, 16);
  44
  45 static IIO_SCAN_EL_TIMESTAMP(12);
  46 static IIO_CONST_ATTR_SCAN_EL_TYPE(timestamp, s, 64, 64);
  47
  48 static struct attribute *adis16400_scan_el_attrs[] = {
  49         &iio_scan_el_in0_supply.dev_attr.attr,
  50         &iio_const_attr_in0_supply_index.dev_attr.attr,
  51         &iio_const_attr_in0_supply_type.dev_attr.attr,
  52         &iio_scan_el_gyro_x.dev_attr.attr,
  53         &iio_const_attr_gyro_x_index.dev_attr.attr,
  54         &iio_scan_el_gyro_y.dev_attr.attr,
  55         &iio_const_attr_gyro_y_index.dev_attr.attr,
  56         &iio_scan_el_gyro_z.dev_attr.attr,
  57         &iio_const_attr_gyro_z_index.dev_attr.attr,
  58         &iio_const_attr_gyro_type.dev_attr.attr,
  59         &iio_scan_el_accel_x.dev_attr.attr,
  60         &iio_const_attr_accel_x_index.dev_attr.attr,
  61         &iio_scan_el_accel_y.dev_attr.attr,
  62         &iio_const_attr_accel_y_index.dev_attr.attr,
  63         &iio_scan_el_accel_z.dev_attr.attr,
  64         &iio_const_attr_accel_z_index.dev_attr.attr,
  65         &iio_const_attr_accel_type.dev_attr.attr,
  66         &iio_scan_el_magn_x.dev_attr.attr,
  67         &iio_const_attr_magn_x_index.dev_attr.attr,
  68         &iio_scan_el_magn_y.dev_attr.attr,
  69         &iio_const_attr_magn_y_index.dev_attr.attr,
  70         &iio_scan_el_magn_z.dev_attr.attr,
  71         &iio_const_attr_magn_z_index.dev_attr.attr,
  72         &iio_const_attr_magn_type.dev_attr.attr,
  73         &iio_scan_el_temp.dev_attr.attr,
  74         &iio_const_attr_temp_index.dev_attr.attr,
  75         &iio_const_attr_temp_type.dev_attr.attr,
  76         &iio_scan_el_in1.dev_attr.attr,
  77         &iio_const_attr_in1_index.dev_attr.attr,
  78         &iio_const_attr_in1_type.dev_attr.attr,
  79         &iio_scan_el_timestamp.dev_attr.attr,
  80         &iio_const_attr_timestamp_index.dev_attr.attr,
  81         &iio_const_attr_timestamp_type.dev_attr.attr,
  82         NULL,
  83 };
  84
  85 static struct attribute_group adis16400_scan_el_group = {
  86         .attrs = adis16400_scan_el_attrs,
  87         .name = "scan_elements",
  88 };
  89
  90 /**
  91  * adis16400_poll_func_th() top half interrupt handler called by trigger
  92  * @private_data:       iio_dev
  93  **/
  94 static void adis16400_poll_func_th(struct iio_dev *indio_dev, s64 time)
  95 {
  96         struct adis16400_state *st = iio_dev_get_devdata(indio_dev);
  97         st->last_timestamp = time;
  98         schedule_work(&st->work_trigger_to_ring);
  99         /* Indicate that this interrupt is being handled */
 100
 101         /* Technically this is trigger related, but without this
 102          * handler running there is currently no way for the interrupt
 103          * to clear.
 104          */
 105 }
 106
 107 /**
 108  * adis16400_spi_read_burst() - read all data registers
 109  * @dev: device associated with child of actual device (iio_dev or iio_trig)
 110  * @rx: somewhere to pass back the value read (min size is 24 bytes)
 111  **/
 112 static int adis16400_spi_read_burst(struct device *dev, u8 *rx)
 113 {
 114         struct spi_message msg;
 115         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 116         struct adis16400_state *st = iio_dev_get_devdata(indio_dev);
 117         u32 old_speed_hz = st->us->max_speed_hz;
 118         int ret;
 119
 120         struct spi_transfer xfers[] = {
 121                 {
 122                         .tx_buf = st->tx,
 123                         .bits_per_word = 8,
 124                         .len = 2,
 125                         .cs_change = 0,
 126                 }, {
 127                         .rx_buf = rx,
 128                         .bits_per_word = 8,
 129                         .len = 24,
 130                         .cs_change = 1,
 131                 },
 132         };
 133
 134         mutex_lock(&st->buf_lock);
 135         st->tx[0] = ADIS16400_READ_REG(ADIS16400_GLOB_CMD);
 136         st->tx[1] = 0;
 137
 138         spi_message_init(&msg);
 139         spi_message_add_tail(&xfers[0], &msg);
 140         spi_message_add_tail(&xfers[1], &msg);
 141
 142         st->us->max_speed_hz = min(ADIS16400_SPI_BURST, old_speed_hz);
 143         spi_setup(st->us);
 144
 145         ret = spi_sync(st->us, &msg);
 146         if (ret)
 147                 dev_err(&st->us->dev, "problem when burst reading");
 148
 149         st->us->max_speed_hz = old_speed_hz;
 150         spi_setup(st->us);
 151         mutex_unlock(&st->buf_lock);
 152         return ret;
 153 }
 154
 155 /* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
 156  * specific to be rolled into the core.
 157  */
 158 static void adis16400_trigger_bh_to_ring(struct work_struct *work_s)
 159 {
 160         struct adis16400_state *st
 161                 = container_of(work_s, struct adis16400_state,
 162                                work_trigger_to_ring);
 163         struct iio_ring_buffer *ring = st->indio_dev->ring;
 164
 165         int i = 0;
 166         s16 *data;
 167         size_t datasize = ring->access.get_bytes_per_datum(ring);
 168
 169         data = kmalloc(datasize , GFP_KERNEL);
 170         if (data == NULL) {
 171                 dev_err(&st->us->dev, "memory alloc failed in ring bh");
 172                 return;
 173         }
 174
 175         if (ring->scan_count)
 176                 if (adis16400_spi_read_burst(&st->indio_dev->dev, st->rx) >= 0)
 177                         for (; i < ring->scan_count; i++)
 178                                 data[i] = be16_to_cpup(
 179                                         (__be16 *)&(st->rx[i*2]));
 180
 181         /* Guaranteed to be aligned with 8 byte boundary */
 182         if (ring->scan_timestamp)
 183                 *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp;
 184
 185         ring->access.store_to(ring,
 186                         (u8 *) data,
 187                         st->last_timestamp);
 188
 189         iio_trigger_notify_done(st->indio_dev->trig);
 190         kfree(data);
 191
 192         return;
 193 }
 194
 195 void adis16400_unconfigure_ring(struct iio_dev *indio_dev)
 196 {
 197         kfree(indio_dev->pollfunc);
 198         iio_sw_rb_free(indio_dev->ring);
 199 }
 200
 201 int adis16400_configure_ring(struct iio_dev *indio_dev)
 202 {
 203         int ret = 0;
 204         struct adis16400_state *st = indio_dev->dev_data;
 205         struct iio_ring_buffer *ring;
 206         INIT_WORK(&st->work_trigger_to_ring, adis16400_trigger_bh_to_ring);
 207
 208         ring = iio_sw_rb_allocate(indio_dev);
 209         if (!ring) {
 210                 ret = -ENOMEM;
 211                 return ret;
 212         }
 213         indio_dev->ring = ring;
 214         /* Effectively select the ring buffer implementation */
 215         iio_ring_sw_register_funcs(&ring->access);
 216         ring->bpe = 2;
 217         ring->scan_el_attrs = &adis16400_scan_el_group;
 218         ring->scan_timestamp = true;
 219         ring->preenable = &iio_sw_ring_preenable;
 220         ring->postenable = &iio_triggered_ring_postenable;
 221         ring->predisable = &iio_triggered_ring_predisable;
 222         ring->owner = THIS_MODULE;
 223
 224         /* Set default scan mode */
 225         iio_scan_mask_set(ring, iio_scan_el_in0_supply.number);
 226         iio_scan_mask_set(ring, iio_scan_el_gyro_x.number);
 227         iio_scan_mask_set(ring, iio_scan_el_gyro_y.number);
 228         iio_scan_mask_set(ring, iio_scan_el_gyro_z.number);
 229         iio_scan_mask_set(ring, iio_scan_el_accel_x.number);
 230         iio_scan_mask_set(ring, iio_scan_el_accel_y.number);
 231         iio_scan_mask_set(ring, iio_scan_el_accel_z.number);
 232         iio_scan_mask_set(ring, iio_scan_el_magn_x.number);
 233         iio_scan_mask_set(ring, iio_scan_el_magn_y.number);
 234         iio_scan_mask_set(ring, iio_scan_el_magn_z.number);
 235         iio_scan_mask_set(ring, iio_scan_el_temp.number);
 236         iio_scan_mask_set(ring, iio_scan_el_in1.number);
 237
 238         ret = iio_alloc_pollfunc(indio_dev, NULL, &adis16400_poll_func_th);
 239         if (ret)
 240                 goto error_iio_sw_rb_free;
 241
 242         indio_dev->modes |= INDIO_RING_TRIGGERED;
 243         return 0;
 244
 245 error_iio_sw_rb_free:
 246         iio_sw_rb_free(indio_dev->ring);
 247         return ret;
 248 }