drivers/staging/iio/meter/ade7758_trigger.c

   1 /*
   2  * ADE7758 Poly Phase Multifunction Energy Metering IC driver
   3  *
   4  * Copyright 2010-2011 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2.
   7  */
   8
   9 #include <linux/interrupt.h>
  10 #include <linux/irq.h>
  11 #include <linux/mutex.h>
  12 #include <linux/device.h>
  13 #include <linux/kernel.h>
  14 #include <linux/sysfs.h>
  15 #include <linux/list.h>
  16 #include <linux/spi/spi.h>
  17
  18 #include "../iio.h"
  19 #include "../sysfs.h"
  20 #include "../trigger.h"
  21 #include "ade7758.h"
  22
  23 /**
  24  * ade7758_data_rdy_trig_poll() the event handler for the data rdy trig
  25  **/
  26 static irqreturn_t ade7758_data_rdy_trig_poll(int irq, void *private)
  27 {
  28         disable_irq_nosync(irq);
  29         iio_trigger_poll(private, iio_get_time_ns());
  30
  31         return IRQ_HANDLED;
  32 }
  33
  34 /**
  35  * ade7758_data_rdy_trigger_set_state() set datardy interrupt state
  36  **/
  37 static int ade7758_data_rdy_trigger_set_state(struct iio_trigger *trig,
  38                                                 bool state)
  39 {
  40         struct ade7758_state *st = trig->private_data;
  41         struct iio_dev *indio_dev = st->indio_dev;
  42
  43         dev_dbg(&indio_dev->dev, "%s (%d)\n", __func__, state);
  44         return ade7758_set_irq(&indio_dev->dev, state);
  45 }
  46
  47 /**
  48  * ade7758_trig_try_reen() try renabling irq for data rdy trigger
  49  * @trig:       the datardy trigger
  50  **/
  51 static int ade7758_trig_try_reen(struct iio_trigger *trig)
  52 {
  53         struct ade7758_state *st = trig->private_data;
  54
  55         enable_irq(st->us->irq);
  56         /* irq reenabled so success! */
  57         return 0;
  58 }
  59
  60 int ade7758_probe_trigger(struct iio_dev *indio_dev)
  61 {
  62         int ret;
  63         struct ade7758_state *st = indio_dev->dev_data;
  64
  65         st->trig = iio_allocate_trigger("%s-dev%d",
  66                                         spi_get_device_id(st->us)->name,
  67                                         indio_dev->id);
  68         if (st->trig == NULL) {
  69                 ret = -ENOMEM;
  70                 goto error_ret;
  71         }
  72
  73         ret = request_irq(st->us->irq,
  74                           ade7758_data_rdy_trig_poll,
  75                           IRQF_TRIGGER_LOW,
  76                           spi_get_device_id(st->us)->name,
  77                           st->trig);
  78         if (ret)
  79                 goto error_free_trig;
  80
  81         st->trig->dev.parent = &st->us->dev;
  82         st->trig->owner = THIS_MODULE;
  83         st->trig->private_data = st;
  84         st->trig->set_trigger_state = &ade7758_data_rdy_trigger_set_state;
  85         st->trig->try_reenable = &ade7758_trig_try_reen;
  86         ret = iio_trigger_register(st->trig);
  87
  88         /* select default trigger */
  89         indio_dev->trig = st->trig;
  90         if (ret)
  91                 goto error_free_irq;
  92
  93         return 0;
  94
  95 error_free_irq:
  96         free_irq(st->us->irq, st->trig);
  97 error_free_trig:
  98         iio_free_trigger(st->trig);
  99 error_ret:
 100         return ret;
 101 }
 102
 103 void ade7758_remove_trigger(struct iio_dev *indio_dev)
 104 {
 105         struct ade7758_state *state = indio_dev->dev_data;
 106
 107         iio_trigger_unregister(state->trig);
 108         free_irq(state->us->irq, state->trig);
 109         iio_free_trigger(state->trig);
 110 }