device.c

/*
 * Copyright (c) 2016-2018, Linaro Ltd.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
#include <sys/file.h>
#include <sys/stat.h>

#include <assert.h>
#include <err.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "device.h"
#include "fastboot.h"
#include "list.h"

#define ARRAY_SIZE(x) ((sizeof(x)/sizeof((x)[0])))

static struct list_head devices = LIST_INIT(devices);

void device_add(struct device *device)
{
	list_add(&devices, &device->node);
}

static void device_lock(struct device *device)
{
	char lock[PATH_MAX];
	int fd;
	int n;

	n = snprintf(lock, sizeof(lock), "/tmp/cdba-%s.lock", device->board);
	if (n >= sizeof(lock))
		errx(1, "failed to build lockfile path");

	fd = open(lock, O_RDONLY | O_CREAT | O_CLOEXEC, 0666);
	if (fd < 0)
		err(1, "failed to open lockfile %s", lock);

	n = flock(fd, LOCK_EX | LOCK_NB);
	if (!n)
		return;

	warnx("board is in use, waiting...");

	n = flock(fd, LOCK_EX);
	if (n < 0)
		err(1, "failed to lock lockfile %s", lock);
}

struct device *device_open(const char *board,
			   struct fastboot_ops *fastboot_ops)
{
	struct device *device;

	list_for_each_entry(device, &devices, node) {
		if (!strcmp(device->board, board))
			goto found;
	}

	return NULL;

found:
	assert(device->open);

	device_lock(device);

	device->cdb = device->open(device);
	if (!device->cdb)
		errx(1, "failed to open device controller");

	device->fastboot = fastboot_open(device->serial, fastboot_ops, NULL);

	return device;
}

int device_power_on(struct device *device)
{
	if (!device)
		return 0;

	assert(device->power_on);

	device->power_on(device);

	return 0;
}

int device_power_off(struct device *device)
{
	if (!device)
		return 0;

	assert(device->power_off);

	device->power_off(device);

	return 0;
}

void device_print_status(struct device *device)
{
	if (device->print_status)
		device->print_status(device);
}

void device_vbus(struct device *device, bool enable)
{
	if (device->vbus)
		device->vbus(device, enable);
}

int device_write(struct device *device, const void *buf, size_t len)
{
	if (!device)
		return 0;

	assert(device->write);

	return device->write(device, buf, len);
}

void device_fastboot_boot(struct device *device)
{
	fastboot_boot(device->fastboot);
}

void device_fastboot_flash_reboot(struct device *device)
{
	fastboot_flash(device->fastboot, "boot");
	fastboot_reboot(device->fastboot);
}

void device_boot(struct device *device, const void *data, size_t len)
{
	if (device->set_active)
		fastboot_set_active(device->fastboot, "a");
	fastboot_download(device->fastboot, data, len);
	device->boot(device);
}

void device_fastboot_key(struct device *device, bool on)
{
	if (device->fastboot_key)
		device->fastboot_key(device, on);
}

void device_send_break(struct device *device)
{
	if (device->send_break)
		device->send_break(device);
}