drivers/staging/iio/meter/ade7758_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 "ade7758.h"
  14
  15 /**
  16  * ade7758_data_rdy_trig_poll() the event handler for the data rdy trig
  17  **/
  18 static irqreturn_t ade7758_data_rdy_trig_poll(int irq, void *private)
  19 {
  20         disable_irq_nosync(irq);
  21         iio_trigger_poll(private, iio_get_time_ns());
  22         return IRQ_HANDLED;
  23 }
  24
  25 static DEVICE_ATTR(name, S_IRUGO, iio_trigger_read_name, NULL);
  26
  27 static struct attribute *ade7758_trigger_attrs[] = {
  28         &dev_attr_name.attr,
  29         NULL,
  30 };
  31
  32 static const struct attribute_group ade7758_trigger_attr_group = {
  33         .attrs = ade7758_trigger_attrs,
  34 };
  35
  36 /**
  37  * ade7758_data_rdy_trigger_set_state() set datardy interrupt state
  38  **/
  39 static int ade7758_data_rdy_trigger_set_state(struct iio_trigger *trig,
  40                                                 bool state)
  41 {
  42         struct ade7758_state *st = trig->private_data;
  43         struct iio_dev *indio_dev = st->indio_dev;
  44
  45         dev_dbg(&indio_dev->dev, "%s (%d)\n", __func__, state);
  46         return ade7758_set_irq(&indio_dev->dev, state);
  47 }
  48
  49 /**
  50  * ade7758_trig_try_reen() try renabling irq for data rdy trigger
  51  * @trig:       the datardy trigger
  52  **/
  53 static int ade7758_trig_try_reen(struct iio_trigger *trig)
  54 {
  55         struct ade7758_state *st = trig->private_data;
  56         enable_irq(st->us->irq);
  57         /* irq reenabled so success! */
  58         return 0;
  59 }
  60
  61 int ade7758_probe_trigger(struct iio_dev *indio_dev)
  62 {
  63         int ret;
  64         struct ade7758_state *st = indio_dev->dev_data;
  65
  66
  67         st->trig = iio_allocate_trigger();
  68         if (st->trig == NULL) {
  69                 ret = -ENOMEM;
  70                 goto error_ret;
  71         }
  72         ret = request_irq(st->us->irq,
  73                           ade7758_data_rdy_trig_poll,
  74                           IRQF_TRIGGER_FALLING, "ade7758",
  75                           st->trig);
  76         if (ret)
  77                 goto error_free_trig;
  78
  79         st->trig->name = kasprintf(GFP_KERNEL,
  80                                 "ade7758-dev%d",
  81                                 indio_dev->id);
  82         if (!st->trig->name) {
  83                 ret = -ENOMEM;
  84                 goto error_free_irq;
  85         }
  86         st->trig->dev.parent = &st->us->dev;
  87         st->trig->owner = THIS_MODULE;
  88         st->trig->private_data = st;
  89         st->trig->set_trigger_state = &ade7758_data_rdy_trigger_set_state;
  90         st->trig->try_reenable = &ade7758_trig_try_reen;
  91         st->trig->control_attrs = &ade7758_trigger_attr_group;
  92         ret = iio_trigger_register(st->trig);
  93
  94         /* select default trigger */
  95         indio_dev->trig = st->trig;
  96         if (ret)
  97                 goto error_free_trig_name;
  98
  99         return 0;
 100
 101 error_free_trig_name:
 102         kfree(st->trig->name);
 103 error_free_irq:
 104         free_irq(st->us->irq, st->trig);
 105 error_free_trig:
 106         iio_free_trigger(st->trig);
 107 error_ret:
 108         return ret;
 109 }
 110
 111 void ade7758_remove_trigger(struct iio_dev *indio_dev)
 112 {
 113         struct ade7758_state *state = indio_dev->dev_data;
 114
 115         iio_trigger_unregister(state->trig);
 116         kfree(state->trig->name);
 117         free_irq(state->us->irq, state->trig);
 118         iio_free_trigger(state->trig);
 119 }