2 * STMicroelectronics sensors trigger library driver
4 * Copyright 2012-2013 STMicroelectronics Inc.
6 * Denis Ciocca <denis.ciocca@st.com>
8 * Licensed under the GPL-2.
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 #include <linux/iio/common/st_sensors.h>
18 #include "st_sensors_core.h"
20 int st_sensors_allocate_trigger(struct iio_dev *indio_dev,
21 const struct iio_trigger_ops *trigger_ops)
24 struct st_sensor_data *sdata = iio_priv(indio_dev);
25 unsigned long irq_trig;
27 sdata->trig = iio_trigger_alloc("%s-trigger", indio_dev->name);
28 if (sdata->trig == NULL) {
29 dev_err(&indio_dev->dev, "failed to allocate iio trigger.\n");
33 irq = sdata->get_irq_data_ready(indio_dev);
34 irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
36 * If the IRQ is triggered on falling edge, we need to mark the
37 * interrupt as active low, if the hardware supports this.
39 if (irq_trig == IRQF_TRIGGER_FALLING) {
40 if (!sdata->sensor_settings->drdy_irq.addr_ihl) {
41 dev_err(&indio_dev->dev,
42 "falling edge specified for IRQ but hardware "
43 "only support rising edge, will request "
45 irq_trig = IRQF_TRIGGER_RISING;
47 /* Set up INT active low i.e. falling edge */
48 err = st_sensors_write_data_with_mask(indio_dev,
49 sdata->sensor_settings->drdy_irq.addr_ihl,
50 sdata->sensor_settings->drdy_irq.mask_ihl, 1);
52 goto iio_trigger_free;
53 dev_info(&indio_dev->dev,
54 "interrupts on the falling edge\n");
56 } else if (irq_trig == IRQF_TRIGGER_RISING) {
57 dev_info(&indio_dev->dev,
58 "interrupts on the rising edge\n");
61 dev_err(&indio_dev->dev,
62 "unsupported IRQ trigger specified (%lx), only "
63 "rising and falling edges supported, enforce "
64 "rising edge\n", irq_trig);
65 irq_trig = IRQF_TRIGGER_RISING;
67 err = request_threaded_irq(irq,
68 iio_trigger_generic_data_rdy_poll,
74 dev_err(&indio_dev->dev, "failed to request trigger IRQ.\n");
75 goto iio_trigger_free;
78 iio_trigger_set_drvdata(sdata->trig, indio_dev);
79 sdata->trig->ops = trigger_ops;
80 sdata->trig->dev.parent = sdata->dev;
82 err = iio_trigger_register(sdata->trig);
84 dev_err(&indio_dev->dev, "failed to register iio trigger.\n");
85 goto iio_trigger_register_error;
87 indio_dev->trig = iio_trigger_get(sdata->trig);
91 iio_trigger_register_error:
92 free_irq(sdata->get_irq_data_ready(indio_dev), sdata->trig);
94 iio_trigger_free(sdata->trig);
97 EXPORT_SYMBOL(st_sensors_allocate_trigger);
99 void st_sensors_deallocate_trigger(struct iio_dev *indio_dev)
101 struct st_sensor_data *sdata = iio_priv(indio_dev);
103 iio_trigger_unregister(sdata->trig);
104 free_irq(sdata->get_irq_data_ready(indio_dev), sdata->trig);
105 iio_trigger_free(sdata->trig);
107 EXPORT_SYMBOL(st_sensors_deallocate_trigger);
109 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
110 MODULE_DESCRIPTION("STMicroelectronics ST-sensors trigger");
111 MODULE_LICENSE("GPL v2");