#define _GNU_SOURCE
// SPDX-License-Identifier: GPL-2.0
/*
 * pcmtest.c - guest-side exerciser for sndpci_race.ko.
 *
 * Usage:
 *   pcmtest close [iters]  - open/start/close one playback substream (V4)
 *   pcmtest link  [iters]  - link two playback substreams, close B while
 *                            the A timer callback walks the group (V5)
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <limits.h>
#include <sched.h>
#include <sound/asound.h>

#define DEV "/dev/snd/pcmC0D0c"

static int set_hw_params(int fd)
{
	struct snd_pcm_hw_params p;
	int i, ret;

	memset(&p, 0, sizeof(p));
	for (i = 0; i <= SNDRV_PCM_HW_PARAM_LAST_MASK -
			SNDRV_PCM_HW_PARAM_FIRST_MASK; i++)
		memset(&p.masks[i], 0xff, sizeof(p.masks[i]));
	for (i = 0; i <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL -
			SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; i++) {
		p.intervals[i].min = 0;
		p.intervals[i].max = UINT_MAX;
		p.intervals[i].integer = 0;
	}
	p.rmask = ~0U;
	ret = ioctl(fd, SNDRV_PCM_IOCTL_HW_REFINE, &p);
	printf("HW_REFINE ret=%d errno=%d\n", ret, errno);
	if (ret < 0)
		return -1;
	printf("refined: rate=%u ch=%u fmt=%u ps=%u periods=%u bs=%u\n",
	       p.intervals[SNDRV_PCM_HW_PARAM_RATE - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL].min,
	       p.intervals[SNDRV_PCM_HW_PARAM_CHANNELS - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL].min,
	       __builtin_ctz(p.masks[SNDRV_PCM_HW_PARAM_FORMAT].bits[0]),
	       p.intervals[SNDRV_PCM_HW_PARAM_PERIOD_SIZE - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL].min,
	       p.intervals[SNDRV_PCM_HW_PARAM_PERIODS - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL].min,
	       p.intervals[SNDRV_PCM_HW_PARAM_BUFFER_SIZE - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL].min);
	ret = ioctl(fd, SNDRV_PCM_IOCTL_HW_PARAMS, &p);
	if (ret < 0) {
		fprintf(stderr, "HW_PARAMS: %s\n", strerror(errno));
		return -1;
	}
	return 0;
}

static int open_stream(void)
{
	int fd = open(DEV, O_RDWR | O_NONBLOCK);

	if (fd < 0)
		fprintf(stderr, "open %s: %s\n", DEV, strerror(errno));
	return fd;
}

static int prepare_stream(int fd)
{
	if (set_hw_params(fd) < 0)
		return -1;
	if (ioctl(fd, SNDRV_PCM_IOCTL_PREPARE, 0) < 0) {
		fprintf(stderr, "PREPARE: %s\n", strerror(errno));
		return -1;
	}
	return 0;
}

static int start_stream(int fd)
{
	if (ioctl(fd, SNDRV_PCM_IOCTL_START, 0) < 0) {
		fprintf(stderr, "START: %s\n", strerror(errno));
		return -1;
	}
	return 0;
}

static int one_close(void)
{
	int fd = open_stream();

	if (fd < 0)
		return -1;
	if (prepare_stream(fd) < 0 || start_stream(fd) < 0) {
		close(fd);
		return -1;
	}
	usleep(10000);
	close(fd);
	return 0;
}

static int one_link(void)
{
	int a = open_stream();
	int b = open_stream();

	if (a < 0 || b < 0)
		return -1;
	if (prepare_stream(a) < 0 || prepare_stream(b) < 0)
		goto out;
	if (ioctl(a, SNDRV_PCM_IOCTL_LINK, b) < 0) {
		fprintf(stderr, "LINK: %s\n", strerror(errno));
		goto out;
	}
	if (start_stream(a) < 0)
		goto out;
	/* Let the A timer callback start walking the linked group. */
	usleep(1500);
	/* Close B while A's callback may be in the group loop. */
	close(b);
	b = -1;
	usleep(1500);
out:
	if (b >= 0)
		close(b);
	if (a >= 0)
		close(a);
	return 0;
}

int main(int argc, char **argv)
{
	cpu_set_t set;

	CPU_ZERO(&set);
	CPU_SET(1, &set);
	sched_setaffinity(0, sizeof(set), &set);
	int i, n = 200;

	if (argc < 2) {
		fprintf(stderr, "usage: %s close|link [iters]\n", argv[0]);
		return 2;
	}
	if (argc > 2)
		n = atoi(argv[2]);
	printf("pcmtest: mode=%s iters=%d\n", argv[1], n);
	for (i = 0; i < n; i++) {
		if (!strcmp(argv[1], "link")) {
			if (one_link() < 0)
				break;
		} else {
			if (one_close() < 0)
				break;
		}
	}
	printf("pcmtest: done i=%d\n", i);
	return 0;
}