2 * Copyright 2011-2012 Analog Devices Inc.
4 * Licensed under the GPL-2.
8 #include <linux/interrupt.h>
9 #include <linux/gpio.h>
10 #include <linux/device.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
14 #include <linux/iio/iio.h>
15 #include <linux/iio/buffer.h>
16 #include <linux/iio/trigger_consumer.h>
17 #include <linux/iio/triggered_buffer.h>
22 * ad7606_trigger_handler_th() th/bh of trigger launched polling to ring buffer
25 static irqreturn_t ad7606_trigger_handler_th_bh(int irq, void *p)
27 struct iio_poll_func *pf = p;
28 struct ad7606_state *st = iio_priv(pf->indio_dev);
30 gpio_set_value(st->pdata->gpio_convst, 1);
36 * ad7606_poll_bh_to_ring() bh of trigger launched polling to ring buffer
37 * @work_s: the work struct through which this was scheduled
39 * Currently there is no option in this driver to disable the saving of
40 * timestamps within the ring.
41 * I think the one copy of this at a time was to avoid problems if the
42 * trigger was set far too high and the reads then locked up the computer.
44 static void ad7606_poll_bh_to_ring(struct work_struct *work_s)
46 struct ad7606_state *st = container_of(work_s, struct ad7606_state,
48 struct iio_dev *indio_dev = iio_priv_to_dev(st);
52 buf = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
56 if (gpio_is_valid(st->pdata->gpio_frstdata)) {
57 ret = st->bops->read_block(st->dev, 1, buf);
60 if (!gpio_get_value(st->pdata->gpio_frstdata)) {
61 /* This should never happen. However
62 * some signal glitch caused by bad PCB desgin or
63 * electrostatic discharge, could cause an extra read
64 * or clock. This allows recovery.
69 ret = st->bops->read_block(st->dev,
70 st->chip_info->num_channels - 1, buf + 2);
74 ret = st->bops->read_block(st->dev,
75 st->chip_info->num_channels, buf);
80 iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
82 gpio_set_value(st->pdata->gpio_convst, 0);
83 iio_trigger_notify_done(indio_dev->trig);
87 int ad7606_register_ring_funcs_and_init(struct iio_dev *indio_dev)
89 struct ad7606_state *st = iio_priv(indio_dev);
91 INIT_WORK(&st->poll_work, &ad7606_poll_bh_to_ring);
93 return iio_triggered_buffer_setup(indio_dev,
94 &ad7606_trigger_handler_th_bh, &ad7606_trigger_handler_th_bh,
98 void ad7606_ring_cleanup(struct iio_dev *indio_dev)
100 iio_triggered_buffer_cleanup(indio_dev);