xref: /linux/drivers/iio/imu/adis_trigger.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Common library for ADIS16XXX devices
4  *
5  * Copyright 2012 Analog Devices Inc.
6  *   Author: Lars-Peter Clausen <lars@metafoo.de>
7  */
8 
9 #include <linux/interrupt.h>
10 #include <linux/kernel.h>
11 #include <linux/spi/spi.h>
12 #include <linux/export.h>
13 
14 #include <linux/iio/iio.h>
15 #include <linux/iio/trigger.h>
16 #include <linux/iio/imu/adis.h>
17 
18 static int adis_data_rdy_trigger_set_state(struct iio_trigger *trig, bool state)
19 {
20 	struct adis *adis = iio_trigger_get_drvdata(trig);
21 
22 	return adis_enable_irq(adis, state);
23 }
24 
25 static const struct iio_trigger_ops adis_trigger_ops = {
26 	.set_trigger_state = &adis_data_rdy_trigger_set_state,
27 };
28 
29 static int adis_validate_irq_flag(struct adis *adis)
30 {
31 	unsigned long direction = adis->irq_flag & IRQF_TRIGGER_MASK;
32 
33 	/* We cannot mask the interrupt so ensure it's not enabled at request */
34 	if (adis->data->unmasked_drdy)
35 		adis->irq_flag |= IRQF_NO_AUTOEN;
36 	/*
37 	 * Typically adis devices without FIFO have data ready either on the
38 	 * rising edge or on the falling edge of the data ready pin.
39 	 * IMU devices with FIFO support have the watermark pin level driven
40 	 * either high or low when the FIFO is filled with the desired number
41 	 * of samples.
42 	 * It defaults to IRQF_TRIGGER_RISING for backward compatibility with
43 	 * devices that don't support changing the pin polarity.
44 	 */
45 	if (direction == IRQF_TRIGGER_NONE) {
46 		adis->irq_flag |= IRQF_TRIGGER_RISING;
47 		return 0;
48 	} else if (direction != IRQF_TRIGGER_RISING &&
49 		   direction != IRQF_TRIGGER_FALLING && !adis->data->has_fifo) {
50 		dev_err(&adis->spi->dev, "Invalid IRQ mask: %08lx\n",
51 			adis->irq_flag);
52 		return -EINVAL;
53 	} else if (direction != IRQF_TRIGGER_HIGH &&
54 		   direction != IRQF_TRIGGER_LOW && adis->data->has_fifo) {
55 		dev_err(&adis->spi->dev, "Invalid IRQ mask: %08lx\n",
56 			adis->irq_flag);
57 		return -EINVAL;
58 	}
59 
60 	return 0;
61 }
62 
63 /**
64  * devm_adis_probe_trigger() - Sets up trigger for a managed adis device
65  * @adis: The adis device
66  * @indio_dev: The IIO device
67  *
68  * Returns 0 on success or a negative error code
69  */
70 int devm_adis_probe_trigger(struct adis *adis, struct iio_dev *indio_dev)
71 {
72 	int ret;
73 
74 	adis->trig = devm_iio_trigger_alloc(&adis->spi->dev, "%s-dev%d",
75 					    indio_dev->name,
76 					    iio_device_id(indio_dev));
77 	if (!adis->trig)
78 		return -ENOMEM;
79 
80 	adis->trig->ops = &adis_trigger_ops;
81 	iio_trigger_set_drvdata(adis->trig, adis);
82 
83 	ret = adis_validate_irq_flag(adis);
84 	if (ret)
85 		return ret;
86 
87 	if (adis->data->has_fifo)
88 		ret = devm_request_threaded_irq(&adis->spi->dev, adis->spi->irq,
89 						NULL,
90 						&iio_trigger_generic_data_rdy_poll,
91 						adis->irq_flag | IRQF_ONESHOT,
92 						indio_dev->name,
93 						adis->trig);
94 	else
95 		ret = devm_request_irq(&adis->spi->dev, adis->spi->irq,
96 				       &iio_trigger_generic_data_rdy_poll,
97 				       adis->irq_flag,
98 				       indio_dev->name,
99 				       adis->trig);
100 	if (ret)
101 		return ret;
102 
103 	return devm_iio_trigger_register(&adis->spi->dev, adis->trig);
104 }
105 EXPORT_SYMBOL_NS_GPL(devm_adis_probe_trigger, IIO_ADISLIB);
106 
107