drivers/staging/iio/imu/adis16400_trigger.c

   1 #include <linux/interrupt.h>
   2 #include <linux/irq.h>
   3 #include <linux/mutex.h>
   4 #include <linux/device.h>
   5 #include <linux/kernel.h>
   6 #include <linux/sysfs.h>
   7 #include <linux/list.h>
   8 #include <linux/spi/spi.h>
   9
  10 #include "../iio.h"
  11 #include "../sysfs.h"
  12 #include "../trigger.h"
  13 #include "adis16400.h"
  14
  15 /**
  16  * adis16400_data_rdy_trig_poll() the event handler for the data rdy trig
  17  **/
  18 static int adis16400_data_rdy_trig_poll(struct iio_dev *dev_info,
  19                                        int index,
  20                                        s64 timestamp,
  21                                        int no_test)
  22 {
  23         struct adis16400_state *st = iio_dev_get_devdata(dev_info);
  24         struct iio_trigger *trig = st->trig;
  25
  26         trig->timestamp = timestamp;
  27         iio_trigger_poll(trig);
  28
  29         return IRQ_HANDLED;
  30 }
  31
  32 IIO_EVENT_SH(data_rdy_trig, &adis16400_data_rdy_trig_poll);
  33
  34 static DEVICE_ATTR(name, S_IRUGO, iio_trigger_read_name, NULL);
  35
  36 static struct attribute *adis16400_trigger_attrs[] = {
  37         &dev_attr_name.attr,
  38         NULL,
  39 };
  40
  41 static const struct attribute_group adis16400_trigger_attr_group = {
  42         .attrs = adis16400_trigger_attrs,
  43 };
  44
  45 /**
  46  * adis16400_data_rdy_trigger_set_state() set datardy interrupt state
  47  **/
  48 static int adis16400_data_rdy_trigger_set_state(struct iio_trigger *trig,
  49                                                 bool state)
  50 {
  51         struct adis16400_state *st = trig->private_data;
  52         struct iio_dev *indio_dev = st->indio_dev;
  53         int ret = 0;
  54
  55         dev_dbg(&indio_dev->dev, "%s (%d)\n", __func__, state);
  56         ret = adis16400_set_irq(&st->indio_dev->dev, state);
  57         if (state == false) {
  58                 iio_remove_event_from_list(&iio_event_data_rdy_trig,
  59                                            &indio_dev->interrupts[0]
  60                                            ->ev_list);
  61                 /* possible quirk with handler currently worked around
  62                    by ensuring the work queue is empty */
  63                 flush_scheduled_work();
  64         } else {
  65                 iio_add_event_to_list(&iio_event_data_rdy_trig,
  66                                       &indio_dev->interrupts[0]->ev_list);
  67         }
  68         return ret;
  69 }
  70
  71 /**
  72  * adis16400_trig_try_reen() try renabling irq for data rdy trigger
  73  * @trig:       the datardy trigger
  74  **/
  75 static int adis16400_trig_try_reen(struct iio_trigger *trig)
  76 {
  77         struct adis16400_state *st = trig->private_data;
  78         enable_irq(st->us->irq);
  79         /* irq reenabled so success! */
  80         return 0;
  81 }
  82
  83 int adis16400_probe_trigger(struct iio_dev *indio_dev)
  84 {
  85         int ret;
  86         struct adis16400_state *st = indio_dev->dev_data;
  87
  88         st->trig = iio_allocate_trigger();
  89         st->trig->name = kmalloc(IIO_TRIGGER_NAME_LENGTH, GFP_KERNEL);
  90         if (!st->trig->name) {
  91                 ret = -ENOMEM;
  92                 goto error_free_trig;
  93         }
  94         snprintf((char *)st->trig->name,
  95                  IIO_TRIGGER_NAME_LENGTH,
  96                  "adis16400-dev%d", indio_dev->id);
  97         st->trig->dev.parent = &st->us->dev;
  98         st->trig->owner = THIS_MODULE;
  99         st->trig->private_data = st;
 100         st->trig->set_trigger_state = &adis16400_data_rdy_trigger_set_state;
 101         st->trig->try_reenable = &adis16400_trig_try_reen;
 102         st->trig->control_attrs = &adis16400_trigger_attr_group;
 103         ret = iio_trigger_register(st->trig);
 104
 105         /* select default trigger */
 106         indio_dev->trig = st->trig;
 107         if (ret)
 108                 goto error_free_trig_name;
 109
 110         return 0;
 111
 112 error_free_trig_name:
 113         kfree(st->trig->name);
 114 error_free_trig:
 115         iio_free_trigger(st->trig);
 116
 117         return ret;
 118 }
 119
 120 void adis16400_remove_trigger(struct iio_dev *indio_dev)
 121 {
 122         struct adis16400_state *state = indio_dev->dev_data;
 123
 124         iio_trigger_unregister(state->trig);
 125         kfree(state->trig->name);
 126         iio_free_trigger(state->trig);
 127 }