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- /*
- * Copyright 2011-2012 Analog Devices Inc.
- *
- * Licensed under the GPL-2.
- *
- */
- #include <linux/interrupt.h>
- #include <linux/gpio.h>
- #include <linux/device.h>
- #include <linux/kernel.h>
- #include <linux/slab.h>
- #include <linux/iio/iio.h>
- #include <linux/iio/buffer.h>
- #include <linux/iio/trigger_consumer.h>
- #include <linux/iio/triggered_buffer.h>
- #include "ad7606.h"
- /**
- * ad7606_trigger_handler_th() th/bh of trigger launched polling to ring buffer
- *
- **/
- static irqreturn_t ad7606_trigger_handler_th_bh(int irq, void *p)
- {
- struct iio_poll_func *pf = p;
- struct ad7606_state *st = iio_priv(pf->indio_dev);
- gpio_set_value(st->pdata->gpio_convst, 1);
- return IRQ_HANDLED;
- }
- /**
- * ad7606_poll_bh_to_ring() bh of trigger launched polling to ring buffer
- * @work_s: the work struct through which this was scheduled
- *
- * Currently there is no option in this driver to disable the saving of
- * timestamps within the ring.
- * I think the one copy of this at a time was to avoid problems if the
- * trigger was set far too high and the reads then locked up the computer.
- **/
- static void ad7606_poll_bh_to_ring(struct work_struct *work_s)
- {
- struct ad7606_state *st = container_of(work_s, struct ad7606_state,
- poll_work);
- struct iio_dev *indio_dev = iio_priv_to_dev(st);
- __u8 *buf;
- int ret;
- buf = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
- if (!buf)
- return;
- if (gpio_is_valid(st->pdata->gpio_frstdata)) {
- ret = st->bops->read_block(st->dev, 1, buf);
- if (ret)
- goto done;
- if (!gpio_get_value(st->pdata->gpio_frstdata)) {
- /* This should never happen. However
- * some signal glitch caused by bad PCB desgin or
- * electrostatic discharge, could cause an extra read
- * or clock. This allows recovery.
- */
- ad7606_reset(st);
- goto done;
- }
- ret = st->bops->read_block(st->dev,
- st->chip_info->num_channels - 1, buf + 2);
- if (ret)
- goto done;
- } else {
- ret = st->bops->read_block(st->dev,
- st->chip_info->num_channels, buf);
- if (ret)
- goto done;
- }
- iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
- done:
- gpio_set_value(st->pdata->gpio_convst, 0);
- iio_trigger_notify_done(indio_dev->trig);
- kfree(buf);
- }
- int ad7606_register_ring_funcs_and_init(struct iio_dev *indio_dev)
- {
- struct ad7606_state *st = iio_priv(indio_dev);
- INIT_WORK(&st->poll_work, &ad7606_poll_bh_to_ring);
- return iio_triggered_buffer_setup(indio_dev,
- &ad7606_trigger_handler_th_bh, &ad7606_trigger_handler_th_bh,
- NULL);
- }
- void ad7606_ring_cleanup(struct iio_dev *indio_dev)
- {
- iio_triggered_buffer_cleanup(indio_dev);
- }
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