kernel/drivers/iio/common/st_sensors/st_sensors_trigger.c

   1 /*
   2  * STMicroelectronics sensors trigger library driver
   3  *
   4  * Copyright 2012-2013 STMicroelectronics Inc.
   5  *
   6  * Denis Ciocca <denis.ciocca@st.com>
   7  *
   8  * Licensed under the GPL-2.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/iio/iio.h>
  15 #include <linux/iio/trigger.h>
  16 #include <linux/interrupt.h>
  17
  18 #include <linux/iio/common/st_sensors.h>
  19
  20
  21 int st_sensors_allocate_trigger(struct iio_dev *indio_dev,
  22                                 const struct iio_trigger_ops *trigger_ops)
  23 {
  24         int err;
  25         struct st_sensor_data *sdata = iio_priv(indio_dev);
  26
  27         sdata->trig = iio_trigger_alloc("%s-trigger", indio_dev->name);
  28         if (sdata->trig == NULL) {
  29                 err = -ENOMEM;
  30                 dev_err(&indio_dev->dev, "failed to allocate iio trigger.\n");
  31                 goto iio_trigger_alloc_error;
  32         }
  33
  34         err = request_threaded_irq(sdata->get_irq_data_ready(indio_dev),
  35                         iio_trigger_generic_data_rdy_poll,
  36                         NULL,
  37                         IRQF_TRIGGER_RISING,
  38                         sdata->trig->name,
  39                         sdata->trig);
  40         if (err) {
  41                 dev_err(&indio_dev->dev, "failed to request trigger IRQ.\n");
  42                 goto request_irq_error;
  43         }
  44
  45         iio_trigger_set_drvdata(sdata->trig, indio_dev);
  46         sdata->trig->ops = trigger_ops;
  47         sdata->trig->dev.parent = sdata->dev;
  48
  49         err = iio_trigger_register(sdata->trig);
  50         if (err < 0) {
  51                 dev_err(&indio_dev->dev, "failed to register iio trigger.\n");
  52                 goto iio_trigger_register_error;
  53         }
  54         indio_dev->trig = iio_trigger_get(sdata->trig);
  55
  56         return 0;
  57
  58 iio_trigger_register_error:
  59         free_irq(sdata->get_irq_data_ready(indio_dev), sdata->trig);
  60 request_irq_error:
  61         iio_trigger_free(sdata->trig);
  62 iio_trigger_alloc_error:
  63         return err;
  64 }
  65 EXPORT_SYMBOL(st_sensors_allocate_trigger);
  66
  67 void st_sensors_deallocate_trigger(struct iio_dev *indio_dev)
  68 {
  69         struct st_sensor_data *sdata = iio_priv(indio_dev);
  70
  71         iio_trigger_unregister(sdata->trig);
  72         free_irq(sdata->get_irq_data_ready(indio_dev), sdata->trig);
  73         iio_trigger_free(sdata->trig);
  74 }
  75 EXPORT_SYMBOL(st_sensors_deallocate_trigger);
  76
  77 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
  78 MODULE_DESCRIPTION("STMicroelectronics ST-sensors trigger");
  79 MODULE_LICENSE("GPL v2");