linux/drivers/spi/spi-slave-time.c

/*
 * SPI slave handler reporting uptime at reception of previous SPI message
 *
 * This SPI slave handler sends the time of reception of the last SPI message
 * as two 32-bit unsigned integers in binary format and in network byte order,
 * representing the number of seconds and fractional seconds (in microseconds)
 * since boot up.
 *
 * Copyright (C) 2016-2017 Glider bvba
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Usage (assuming /dev/spidev2.0 corresponds to the SPI master on the remote
 * system):
 *
 *   # spidev_test -D /dev/spidev2.0 -p dummy-8B
 *   spi mode: 0x0
 *   bits per word: 8
 *   max speed: 500000 Hz (500 KHz)
 *   RX | 00 00 04 6D 00 09 5B BB ...
 *		^^^^^    ^^^^^^^^
 *		seconds  microseconds
 */

#include <linux/completion.h>
#include <linux/module.h>
#include <linux/sched/clock.h>
#include <linux/spi/spi.h>


struct spi_slave_time_priv { … };

static int spi_slave_time_submit(struct spi_slave_time_priv *priv);

static void spi_slave_time_complete(void *arg)
{ … }

static int spi_slave_time_submit(struct spi_slave_time_priv *priv)
{ … }

static int spi_slave_time_probe(struct spi_device *spi)
{ … }

static void spi_slave_time_remove(struct spi_device *spi)
{ … }

static struct spi_driver spi_slave_time_driver = …;
module_spi_driver(…) …;

MODULE_AUTHOR(…) …;
MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;