drivers/staging/iio/gyro/adis16260_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 "adis16260.h"
  19
  20 static IIO_SCAN_EL_C(supply, ADIS16260_SCAN_SUPPLY, IIO_UNSIGNED(12),
  21                 ADIS16260_SUPPLY_OUT, NULL);
  22 static IIO_SCAN_EL_C(gyro, ADIS16260_SCAN_GYRO, IIO_SIGNED(14),
  23                 ADIS16260_GYRO_OUT, NULL);
  24 static IIO_SCAN_EL_C(aux_adc, ADIS16260_SCAN_AUX_ADC, IIO_SIGNED(14),
  25                 ADIS16260_AUX_ADC, NULL);
  26 static IIO_SCAN_EL_C(temp, ADIS16260_SCAN_TEMP, IIO_UNSIGNED(12),
  27                 ADIS16260_TEMP_OUT, NULL);
  28 static IIO_SCAN_EL_C(angl, ADIS16260_SCAN_ANGL, IIO_UNSIGNED(12),
  29                 ADIS16260_ANGL_OUT, NULL);
  30
  31 static IIO_SCAN_EL_TIMESTAMP(5);
  32
  33 static struct attribute *adis16260_scan_el_attrs[] = {
  34         &iio_scan_el_supply.dev_attr.attr,
  35         &iio_scan_el_gyro.dev_attr.attr,
  36         &iio_scan_el_aux_adc.dev_attr.attr,
  37         &iio_scan_el_temp.dev_attr.attr,
  38         &iio_scan_el_angl.dev_attr.attr,
  39         &iio_scan_el_timestamp.dev_attr.attr,
  40         NULL,
  41 };
  42
  43 static struct attribute_group adis16260_scan_el_group = {
  44         .attrs = adis16260_scan_el_attrs,
  45         .name = "scan_elements",
  46 };
  47
  48 /**
  49  * adis16260_poll_func_th() top half interrupt handler called by trigger
  50  * @private_data:       iio_dev
  51  **/
  52 static void adis16260_poll_func_th(struct iio_dev *indio_dev, s64 time)
  53 {
  54         struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
  55         st->last_timestamp = time;
  56         schedule_work(&st->work_trigger_to_ring);
  57 }
  58
  59 /**
  60  * adis16260_read_ring_data() read data registers which will be placed into ring
  61  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  62  * @rx: somewhere to pass back the value read
  63  **/
  64 static int adis16260_read_ring_data(struct device *dev, u8 *rx)
  65 {
  66         struct spi_message msg;
  67         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  68         struct adis16260_state *st = iio_dev_get_devdata(indio_dev);
  69         struct spi_transfer xfers[ADIS16260_OUTPUTS + 1];
  70         int ret;
  71         int i;
  72
  73         mutex_lock(&st->buf_lock);
  74
  75         spi_message_init(&msg);
  76
  77         memset(xfers, 0, sizeof(xfers));
  78         for (i = 0; i <= ADIS16260_OUTPUTS; i++) {
  79                 xfers[i].bits_per_word = 8;
  80                 xfers[i].cs_change = 1;
  81                 xfers[i].len = 2;
  82                 xfers[i].delay_usecs = 30;
  83                 xfers[i].tx_buf = st->tx + 2 * i;
  84                 if (i < 2) /* SUPPLY_OUT:0x02 GYRO_OUT:0x04 */
  85                         st->tx[2 * i]
  86                                 = ADIS16260_READ_REG(ADIS16260_SUPPLY_OUT
  87                                                 + 2 * i);
  88                 else /* 0x06 to 0x09 is reserved */
  89                         st->tx[2 * i]
  90                                 = ADIS16260_READ_REG(ADIS16260_SUPPLY_OUT
  91                                                 + 2 * i + 4);
  92                 st->tx[2 * i + 1] = 0;
  93                 if (i >= 1)
  94                         xfers[i].rx_buf = rx + 2 * (i - 1);
  95                 spi_message_add_tail(&xfers[i], &msg);
  96         }
  97
  98         ret = spi_sync(st->us, &msg);
  99         if (ret)
 100                 dev_err(&st->us->dev, "problem when burst reading");
 101
 102         mutex_unlock(&st->buf_lock);
 103
 104         return ret;
 105 }
 106
 107
 108 static void adis16260_trigger_bh_to_ring(struct work_struct *work_s)
 109 {
 110         struct adis16260_state *st
 111                 = container_of(work_s, struct adis16260_state,
 112                                 work_trigger_to_ring);
 113
 114         int i = 0;
 115         s16 *data;
 116         size_t datasize = st->indio_dev
 117                 ->ring->access.get_bpd(st->indio_dev->ring);
 118
 119         data = kmalloc(datasize , GFP_KERNEL);
 120         if (data == NULL) {
 121                 dev_err(&st->us->dev, "memory alloc failed in ring bh");
 122                 return;
 123         }
 124
 125         if (st->indio_dev->scan_count)
 126                 if (adis16260_read_ring_data(&st->indio_dev->dev, st->rx) >= 0)
 127                         for (; i < st->indio_dev->scan_count; i++)
 128                                 data[i] = be16_to_cpup(
 129                                         (__be16 *)&(st->rx[i*2]));
 130
 131         /* Guaranteed to be aligned with 8 byte boundary */
 132         if (st->indio_dev->scan_timestamp)
 133                 *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp;
 134
 135         st->indio_dev->ring->access.store_to(st->indio_dev->ring,
 136                         (u8 *)data,
 137                         st->last_timestamp);
 138
 139         iio_trigger_notify_done(st->indio_dev->trig);
 140         kfree(data);
 141
 142         return;
 143 }
 144
 145 void adis16260_unconfigure_ring(struct iio_dev *indio_dev)
 146 {
 147         kfree(indio_dev->pollfunc);
 148         iio_sw_rb_free(indio_dev->ring);
 149 }
 150
 151 int adis16260_configure_ring(struct iio_dev *indio_dev)
 152 {
 153         int ret = 0;
 154         struct adis16260_state *st = indio_dev->dev_data;
 155         struct iio_ring_buffer *ring;
 156         INIT_WORK(&st->work_trigger_to_ring, adis16260_trigger_bh_to_ring);
 157         /* Set default scan mode */
 158
 159         iio_scan_mask_set(indio_dev, iio_scan_el_supply.number);
 160         iio_scan_mask_set(indio_dev, iio_scan_el_gyro.number);
 161         iio_scan_mask_set(indio_dev, iio_scan_el_aux_adc.number);
 162         iio_scan_mask_set(indio_dev, iio_scan_el_temp.number);
 163         iio_scan_mask_set(indio_dev, iio_scan_el_angl.number);
 164         indio_dev->scan_timestamp = true;
 165
 166         indio_dev->scan_el_attrs = &adis16260_scan_el_group;
 167
 168         ring = iio_sw_rb_allocate(indio_dev);
 169         if (!ring) {
 170                 ret = -ENOMEM;
 171                 return ret;
 172         }
 173         indio_dev->ring = ring;
 174         /* Effectively select the ring buffer implementation */
 175         iio_ring_sw_register_funcs(&ring->access);
 176         ring->bpe = 2;
 177         ring->preenable = &iio_sw_ring_preenable;
 178         ring->postenable = &iio_triggered_ring_postenable;
 179         ring->predisable = &iio_triggered_ring_predisable;
 180         ring->owner = THIS_MODULE;
 181
 182         ret = iio_alloc_pollfunc(indio_dev, NULL, &adis16260_poll_func_th);
 183         if (ret)
 184                 goto error_iio_sw_rb_free;
 185
 186         indio_dev->modes |= INDIO_RING_TRIGGERED;
 187         return 0;
 188
 189 error_iio_sw_rb_free:
 190         iio_sw_rb_free(indio_dev->ring);
 191         return ret;
 192 }