WSL2-Linux-Kernel/drivers/iio/imu/adis_buffer.c

160 строки
4.0 KiB
C

/*
* Common library for ADIS16XXX devices
*
* Copyright 2012 Analog Devices Inc.
* Author: Lars-Peter Clausen <lars@metafoo.de>
*
* Licensed under the GPL-2 or later.
*/
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/kernel.h>
#include <linux/spi/spi.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 <linux/iio/imu/adis.h>
int adis_update_scan_mode(struct iio_dev *indio_dev,
const unsigned long *scan_mask)
{
struct adis *adis = iio_device_get_drvdata(indio_dev);
const struct iio_chan_spec *chan;
unsigned int scan_count;
unsigned int i, j;
__be16 *tx, *rx;
kfree(adis->xfer);
kfree(adis->buffer);
scan_count = indio_dev->scan_bytes / 2;
adis->xfer = kcalloc(scan_count + 1, sizeof(*adis->xfer), GFP_KERNEL);
if (!adis->xfer)
return -ENOMEM;
adis->buffer = kzalloc(indio_dev->scan_bytes * 2, GFP_KERNEL);
if (!adis->buffer)
return -ENOMEM;
rx = adis->buffer;
tx = rx + indio_dev->scan_bytes;
spi_message_init(&adis->msg);
for (j = 0; j <= scan_count; j++) {
adis->xfer[j].bits_per_word = 8;
if (j != scan_count)
adis->xfer[j].cs_change = 1;
adis->xfer[j].len = 2;
adis->xfer[j].delay_usecs = adis->data->read_delay;
if (j < scan_count)
adis->xfer[j].tx_buf = &tx[j];
if (j >= 1)
adis->xfer[j].rx_buf = &rx[j - 1];
spi_message_add_tail(&adis->xfer[j], &adis->msg);
}
chan = indio_dev->channels;
for (i = 0; i < indio_dev->num_channels; i++, chan++) {
if (!test_bit(chan->scan_index, scan_mask))
continue;
*tx++ = cpu_to_be16(chan->address << 8);
}
return 0;
}
EXPORT_SYMBOL_GPL(adis_update_scan_mode);
static irqreturn_t adis_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct adis *adis = iio_device_get_drvdata(indio_dev);
int ret;
if (!adis->buffer)
return -ENOMEM;
ret = spi_sync(adis->spi, &adis->msg);
if (ret)
dev_err(&adis->spi->dev, "Failed to read data: %d", ret);
/* Guaranteed to be aligned with 8 byte boundary */
if (indio_dev->scan_timestamp) {
void *b = adis->buffer + indio_dev->scan_bytes - sizeof(s64);
*(s64 *)b = pf->timestamp;
}
iio_push_to_buffers(indio_dev, adis->buffer);
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
/**
* adis_setup_buffer_and_trigger() - Sets up buffer and trigger for the adis device
* @adis: The adis device.
* @indio_dev: The IIO device.
* @trigger_handler: Optional trigger handler, may be NULL.
*
* Returns 0 on success, a negative error code otherwise.
*
* This function sets up the buffer and trigger for a adis devices. If
* 'trigger_handler' is NULL the default trigger handler will be used. The
* default trigger handler will simply read the registers assigned to the
* currently active channels.
*
* adis_cleanup_buffer_and_trigger() should be called to free the resources
* allocated by this function.
*/
int adis_setup_buffer_and_trigger(struct adis *adis, struct iio_dev *indio_dev,
irqreturn_t (*trigger_handler)(int, void *))
{
int ret;
if (!trigger_handler)
trigger_handler = adis_trigger_handler;
ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
trigger_handler, NULL);
if (ret)
return ret;
if (adis->spi->irq) {
ret = adis_probe_trigger(adis, indio_dev);
if (ret)
goto error_buffer_cleanup;
}
return 0;
error_buffer_cleanup:
iio_triggered_buffer_cleanup(indio_dev);
return ret;
}
EXPORT_SYMBOL_GPL(adis_setup_buffer_and_trigger);
/**
* adis_cleanup_buffer_and_trigger() - Free buffer and trigger resources
* @adis: The adis device.
* @indio_dev: The IIO device.
*
* Frees resources allocated by adis_setup_buffer_and_trigger()
*/
void adis_cleanup_buffer_and_trigger(struct adis *adis,
struct iio_dev *indio_dev)
{
if (adis->spi->irq)
adis_remove_trigger(adis);
kfree(adis->buffer);
kfree(adis->xfer);
iio_triggered_buffer_cleanup(indio_dev);
}
EXPORT_SYMBOL_GPL(adis_cleanup_buffer_and_trigger);