![Michael Hennerich](/assets/img/avatar_default.png)
drivers/staging/iio/adc/ad7298_ring.c:97:37: warning: 'time_ns' may be used uninitialized in this function [-Wmaybe-uninitialized] Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
115 lines
2.8 KiB
C
115 lines
2.8 KiB
C
/*
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* AD7298 SPI ADC driver
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*
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* Copyright 2011-2012 Analog Devices Inc.
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*
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* Licensed under the GPL-2.
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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 "ad7298.h"
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/**
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* ad7298_update_scan_mode() setup the spi transfer buffer for the new scan mask
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**/
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int ad7298_update_scan_mode(struct iio_dev *indio_dev,
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const unsigned long *active_scan_mask)
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{
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struct ad7298_state *st = iio_priv(indio_dev);
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int i, m;
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unsigned short command;
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int scan_count;
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/* Now compute overall size */
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scan_count = bitmap_weight(active_scan_mask, indio_dev->masklength);
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command = AD7298_WRITE | st->ext_ref;
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for (i = 0, m = AD7298_CH(0); i < AD7298_MAX_CHAN; i++, m >>= 1)
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if (test_bit(i, active_scan_mask))
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command |= m;
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st->tx_buf[0] = cpu_to_be16(command);
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/* build spi ring message */
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st->ring_xfer[0].tx_buf = &st->tx_buf[0];
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st->ring_xfer[0].len = 2;
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st->ring_xfer[0].cs_change = 1;
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st->ring_xfer[1].tx_buf = &st->tx_buf[1];
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st->ring_xfer[1].len = 2;
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st->ring_xfer[1].cs_change = 1;
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spi_message_init(&st->ring_msg);
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spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
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spi_message_add_tail(&st->ring_xfer[1], &st->ring_msg);
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for (i = 0; i < scan_count; i++) {
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st->ring_xfer[i + 2].rx_buf = &st->rx_buf[i];
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st->ring_xfer[i + 2].len = 2;
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st->ring_xfer[i + 2].cs_change = 1;
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spi_message_add_tail(&st->ring_xfer[i + 2], &st->ring_msg);
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}
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/* make sure last transfer cs_change is not set */
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st->ring_xfer[i + 1].cs_change = 0;
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return 0;
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}
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/**
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* ad7298_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 ad7298_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 ad7298_state *st = iio_priv(indio_dev);
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struct iio_buffer *ring = indio_dev->buffer;
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s64 time_ns = 0;
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__u16 buf[16];
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int b_sent, i;
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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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if (indio_dev->scan_timestamp) {
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time_ns = iio_get_time_ns();
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memcpy((u8 *)buf + indio_dev->scan_bytes - sizeof(s64),
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&time_ns, sizeof(time_ns));
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}
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for (i = 0; i < bitmap_weight(indio_dev->active_scan_mask,
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indio_dev->masklength); i++)
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buf[i] = be16_to_cpu(st->rx_buf[i]);
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indio_dev->buffer->access->store_to(ring, (u8 *)buf, time_ns);
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done:
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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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int ad7298_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, NULL,
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&ad7298_trigger_handler, NULL);
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}
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void ad7298_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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