drivers/staging/iio/imu/adis16350_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 "adis16350.h"
  19
  20 static IIO_SCAN_EL_C(in_supply, ADIS16350_SCAN_SUPPLY, IIO_UNSIGNED(12),
  21                 ADIS16350_SUPPLY_OUT, NULL);
  22 static IIO_CONST_ATTR_SCAN_EL_TYPE(in_supply, u, 12, 16);
  23
  24 static IIO_SCAN_EL_C(gyro_x, ADIS16350_SCAN_GYRO_X, IIO_SIGNED(14),
  25                 ADIS16350_XGYRO_OUT, NULL);
  26 static IIO_SCAN_EL_C(gyro_y, ADIS16350_SCAN_GYRO_Y, IIO_SIGNED(14),
  27                 ADIS16350_YGYRO_OUT, NULL);
  28 static IIO_SCAN_EL_C(gyro_z, ADIS16350_SCAN_GYRO_Z, IIO_SIGNED(14),
  29                 ADIS16350_ZGYRO_OUT, NULL);
  30 static IIO_CONST_ATTR_SCAN_EL_TYPE(gyro, s, 14, 16);
  31
  32 static IIO_SCAN_EL_C(accel_x, ADIS16350_SCAN_ACC_X, IIO_SIGNED(14),
  33                 ADIS16350_XACCL_OUT, NULL);
  34 static IIO_SCAN_EL_C(accel_y, ADIS16350_SCAN_ACC_Y, IIO_SIGNED(14),
  35                 ADIS16350_YACCL_OUT, NULL);
  36 static IIO_SCAN_EL_C(accel_z, ADIS16350_SCAN_ACC_Z, IIO_SIGNED(14),
  37                 ADIS16350_ZACCL_OUT, NULL);
  38 static IIO_CONST_ATTR_SCAN_EL_TYPE(accel, s, 14, 16);
  39
  40 static IIO_SCAN_EL_C(temp_x, ADIS16350_SCAN_TEMP_X, IIO_SIGNED(12),
  41                 ADIS16350_XTEMP_OUT, NULL);
  42 static IIO_SCAN_EL_C(temp_y, ADIS16350_SCAN_TEMP_Y, IIO_SIGNED(12),
  43                 ADIS16350_YTEMP_OUT, NULL);
  44 static IIO_SCAN_EL_C(temp_z, ADIS16350_SCAN_TEMP_Z, IIO_SIGNED(12),
  45                 ADIS16350_ZTEMP_OUT, NULL);
  46 static IIO_CONST_ATTR_SCAN_EL_TYPE(temp, s, 12, 16);
  47
  48 static IIO_SCAN_EL_C(in0, ADIS16350_SCAN_ADC_0, IIO_UNSIGNED(12),
  49                 ADIS16350_AUX_ADC, NULL);
  50 static IIO_CONST_ATTR_SCAN_EL_TYPE(in0, u, 12, 16);
  51
  52 static IIO_SCAN_EL_TIMESTAMP(11);
  53 static IIO_CONST_ATTR_SCAN_EL_TYPE(timestamp, s, 64, 64);
  54
  55 static struct attribute *adis16350_scan_el_attrs[] = {
  56         &iio_scan_el_in_supply.dev_attr.attr,
  57         &iio_const_attr_in_supply_type.dev_attr.attr,
  58         &iio_scan_el_gyro_x.dev_attr.attr,
  59         &iio_scan_el_gyro_y.dev_attr.attr,
  60         &iio_scan_el_gyro_z.dev_attr.attr,
  61         &iio_const_attr_gyro_type.dev_attr.attr,
  62         &iio_scan_el_accel_x.dev_attr.attr,
  63         &iio_scan_el_accel_y.dev_attr.attr,
  64         &iio_scan_el_accel_z.dev_attr.attr,
  65         &iio_const_attr_accel_type.dev_attr.attr,
  66         &iio_scan_el_temp_x.dev_attr.attr,
  67         &iio_scan_el_temp_y.dev_attr.attr,
  68         &iio_scan_el_temp_z.dev_attr.attr,
  69         &iio_const_attr_temp_type.dev_attr.attr,
  70         &iio_scan_el_in0.dev_attr.attr,
  71         &iio_const_attr_in0_type.dev_attr.attr,
  72         &iio_scan_el_timestamp.dev_attr.attr,
  73         &iio_const_attr_timestamp_type.dev_attr.attr,
  74         NULL,
  75 };
  76
  77 static struct attribute_group adis16350_scan_el_group = {
  78         .attrs = adis16350_scan_el_attrs,
  79         .name = "scan_elements",
  80 };
  81
  82 /**
  83  * adis16350_poll_func_th() top half interrupt handler called by trigger
  84  * @private_data:       iio_dev
  85  **/
  86 static void adis16350_poll_func_th(struct iio_dev *indio_dev, s64 time)
  87 {
  88         struct adis16350_state *st = iio_dev_get_devdata(indio_dev);
  89         st->last_timestamp = time;
  90         schedule_work(&st->work_trigger_to_ring);
  91 }
  92
  93 /**
  94  * adis16350_spi_read_burst() - read all data registers
  95  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  96  * @rx: somewhere to pass back the value read (min size is 24 bytes)
  97  **/
  98 static int adis16350_spi_read_burst(struct device *dev, u8 *rx)
  99 {
 100         struct spi_message msg;
 101         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 102         struct adis16350_state *st = iio_dev_get_devdata(indio_dev);
 103         u32 old_speed_hz = st->us->max_speed_hz;
 104         int ret;
 105
 106         struct spi_transfer xfers[] = {
 107                 {
 108                         .tx_buf = st->tx,
 109                         .bits_per_word = 8,
 110                         .len = 2,
 111                         .cs_change = 0,
 112                 }, {
 113                         .rx_buf = rx,
 114                         .bits_per_word = 8,
 115                         .len = 22,
 116                         .cs_change = 0,
 117                 },
 118         };
 119
 120         mutex_lock(&st->buf_lock);
 121         st->tx[0] = ADIS16350_READ_REG(ADIS16350_GLOB_CMD);
 122         st->tx[1] = 0;
 123
 124         spi_message_init(&msg);
 125         spi_message_add_tail(&xfers[0], &msg);
 126         spi_message_add_tail(&xfers[1], &msg);
 127
 128         st->us->max_speed_hz = ADIS16350_SPI_BURST;
 129         spi_setup(st->us);
 130
 131         ret = spi_sync(st->us, &msg);
 132         if (ret)
 133                 dev_err(&st->us->dev, "problem when burst reading");
 134
 135         st->us->max_speed_hz = old_speed_hz;
 136         spi_setup(st->us);
 137         mutex_unlock(&st->buf_lock);
 138         return ret;
 139 }
 140
 141 /* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
 142  * specific to be rolled into the core.
 143  */
 144 static void adis16350_trigger_bh_to_ring(struct work_struct *work_s)
 145 {
 146         struct adis16350_state *st
 147                 = container_of(work_s, struct adis16350_state,
 148                                work_trigger_to_ring);
 149         struct iio_ring_buffer *ring = st->indio_dev->ring;
 150
 151         int i = 0;
 152         s16 *data;
 153         size_t datasize = ring->access.get_bytes_per_datum(ring);
 154
 155         data = kmalloc(datasize , GFP_KERNEL);
 156         if (data == NULL) {
 157                 dev_err(&st->us->dev, "memory alloc failed in ring bh");
 158                 return;
 159         }
 160
 161         if (ring->scan_count)
 162                 if (adis16350_spi_read_burst(&st->indio_dev->dev, st->rx) >= 0)
 163                         for (; i < ring->scan_count; i++)
 164                                 data[i] = be16_to_cpup(
 165                                         (__be16 *)&(st->rx[i*2]));
 166
 167         /* Guaranteed to be aligned with 8 byte boundary */
 168         if (ring->scan_timestamp)
 169                 *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp;
 170
 171         ring->access.store_to(ring,
 172                         (u8 *)data,
 173                         st->last_timestamp);
 174
 175         iio_trigger_notify_done(st->indio_dev->trig);
 176         kfree(data);
 177
 178         return;
 179 }
 180
 181 void adis16350_unconfigure_ring(struct iio_dev *indio_dev)
 182 {
 183         kfree(indio_dev->pollfunc);
 184         iio_sw_rb_free(indio_dev->ring);
 185 }
 186
 187 int adis16350_configure_ring(struct iio_dev *indio_dev)
 188 {
 189         int ret = 0;
 190         struct adis16350_state *st = indio_dev->dev_data;
 191         struct iio_ring_buffer *ring;
 192         INIT_WORK(&st->work_trigger_to_ring, adis16350_trigger_bh_to_ring);
 193
 194         ring = iio_sw_rb_allocate(indio_dev);
 195         if (!ring) {
 196                 ret = -ENOMEM;
 197                 return ret;
 198         }
 199         indio_dev->ring = ring;
 200         /* Effectively select the ring buffer implementation */
 201         iio_ring_sw_register_funcs(&ring->access);
 202         ring->bpe = 2;
 203         ring->scan_el_attrs = &adis16350_scan_el_group;
 204         ring->scan_timestamp = true;
 205         ring->preenable = &iio_sw_ring_preenable;
 206         ring->postenable = &iio_triggered_ring_postenable;
 207         ring->predisable = &iio_triggered_ring_predisable;
 208         ring->owner = THIS_MODULE;
 209
 210         /* Set default scan mode */
 211         iio_scan_mask_set(ring, iio_scan_el_in_supply.number);
 212         iio_scan_mask_set(ring, iio_scan_el_gyro_x.number);
 213         iio_scan_mask_set(ring, iio_scan_el_gyro_y.number);
 214         iio_scan_mask_set(ring, iio_scan_el_gyro_z.number);
 215         iio_scan_mask_set(ring, iio_scan_el_accel_x.number);
 216         iio_scan_mask_set(ring, iio_scan_el_accel_y.number);
 217         iio_scan_mask_set(ring, iio_scan_el_accel_z.number);
 218         iio_scan_mask_set(ring, iio_scan_el_temp_x.number);
 219         iio_scan_mask_set(ring, iio_scan_el_temp_y.number);
 220         iio_scan_mask_set(ring, iio_scan_el_temp_z.number);
 221         iio_scan_mask_set(ring, iio_scan_el_in0.number);
 222
 223         ret = iio_alloc_pollfunc(indio_dev, NULL, &adis16350_poll_func_th);
 224         if (ret)
 225                 goto error_iio_sw_rb_free;
 226
 227         indio_dev->modes |= INDIO_RING_TRIGGERED;
 228         return 0;
 229
 230 error_iio_sw_rb_free:
 231         iio_sw_rb_free(indio_dev->ring);
 232         return ret;
 233 }
 234