![Lars-Peter Clausen](/assets/img/avatar_default.png)
The interrupt handler should only ever return one of the three irqreturn_t constants and not an error code. Also make sure to always call iio_trigger_notify_done before leaving the trigger handler. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
123 lines
3 KiB
C
123 lines
3 KiB
C
/*
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* Copyright 2010-2012 Analog Devices Inc.
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* Copyright (C) 2008 Jonathan Cameron
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*
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* Licensed under the GPL-2.
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*
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* ad7887_ring.c
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*/
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#include <linux/interrupt.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/spi/spi.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/buffer.h>
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#include <linux/iio/trigger_consumer.h>
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#include <linux/iio/triggered_buffer.h>
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#include "ad7887.h"
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/**
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* ad7887_ring_preenable() setup the parameters of the ring before enabling
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*
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* The complex nature of the setting of the nuber of bytes per datum is due
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* to this driver currently ensuring that the timestamp is stored at an 8
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* byte boundary.
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**/
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static int ad7887_ring_preenable(struct iio_dev *indio_dev)
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{
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struct ad7887_state *st = iio_priv(indio_dev);
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int ret;
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ret = iio_sw_buffer_preenable(indio_dev);
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if (ret < 0)
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return ret;
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/* We know this is a single long so can 'cheat' */
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switch (*indio_dev->active_scan_mask) {
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case (1 << 0):
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st->ring_msg = &st->msg[AD7887_CH0];
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break;
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case (1 << 1):
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st->ring_msg = &st->msg[AD7887_CH1];
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/* Dummy read: push CH1 setting down to hardware */
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spi_sync(st->spi, st->ring_msg);
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break;
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case ((1 << 1) | (1 << 0)):
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st->ring_msg = &st->msg[AD7887_CH0_CH1];
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break;
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}
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return 0;
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}
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static int ad7887_ring_postdisable(struct iio_dev *indio_dev)
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{
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struct ad7887_state *st = iio_priv(indio_dev);
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/* dummy read: restore default CH0 settin */
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return spi_sync(st->spi, &st->msg[AD7887_CH0]);
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}
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/**
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* ad7887_trigger_handler() bh of trigger launched polling to ring buffer
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*
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* Currently there is no option in this driver to disable the saving of
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* timestamps within the ring.
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**/
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static irqreturn_t ad7887_trigger_handler(int irq, void *p)
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{
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struct iio_poll_func *pf = p;
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struct iio_dev *indio_dev = pf->indio_dev;
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struct ad7887_state *st = iio_priv(indio_dev);
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s64 time_ns;
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__u8 *buf;
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int b_sent;
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unsigned int bytes = bitmap_weight(indio_dev->active_scan_mask,
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indio_dev->masklength) *
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st->chip_info->channel[0].scan_type.storagebits / 8;
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buf = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
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if (buf == NULL)
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goto done;
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b_sent = spi_sync(st->spi, st->ring_msg);
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if (b_sent)
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goto done;
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time_ns = iio_get_time_ns();
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memcpy(buf, st->data, bytes);
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if (indio_dev->scan_timestamp)
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memcpy(buf + indio_dev->scan_bytes - sizeof(s64),
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&time_ns, sizeof(time_ns));
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indio_dev->buffer->access->store_to(indio_dev->buffer, buf, time_ns);
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done:
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kfree(buf);
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iio_trigger_notify_done(indio_dev->trig);
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return IRQ_HANDLED;
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}
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static const struct iio_buffer_setup_ops ad7887_ring_setup_ops = {
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.preenable = &ad7887_ring_preenable,
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.postenable = &iio_triggered_buffer_postenable,
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.predisable = &iio_triggered_buffer_predisable,
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.postdisable = &ad7887_ring_postdisable,
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};
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int ad7887_register_ring_funcs_and_init(struct iio_dev *indio_dev)
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{
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return iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
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&ad7887_trigger_handler, &ad7887_ring_setup_ops);
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}
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void ad7887_ring_cleanup(struct iio_dev *indio_dev)
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{
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iio_triggered_buffer_cleanup(indio_dev);
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}
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