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-rw-r--r--tools/gpio/gpio-event-mon.c241
1 files changed, 241 insertions, 0 deletions
diff --git a/tools/gpio/gpio-event-mon.c b/tools/gpio/gpio-event-mon.c
new file mode 100644
index 0000000000..5dee2b98ab
--- /dev/null
+++ b/tools/gpio/gpio-event-mon.c
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * gpio-event-mon - monitor GPIO line events from userspace
+ *
+ * Copyright (C) 2016 Linus Walleij
+ *
+ * Usage:
+ * gpio-event-mon -n <device-name> -o <offset>
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <dirent.h>
+#include <errno.h>
+#include <string.h>
+#include <poll.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <inttypes.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <linux/gpio.h>
+#include "gpio-utils.h"
+
+int monitor_device(const char *device_name,
+ unsigned int *lines,
+ unsigned int num_lines,
+ struct gpio_v2_line_config *config,
+ unsigned int loops)
+{
+ struct gpio_v2_line_values values;
+ char *chrdev_name;
+ int cfd, lfd;
+ int ret;
+ int i = 0;
+
+ ret = asprintf(&chrdev_name, "/dev/%s", device_name);
+ if (ret < 0)
+ return -ENOMEM;
+
+ cfd = open(chrdev_name, 0);
+ if (cfd == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to open %s\n", chrdev_name);
+ goto exit_free_name;
+ }
+
+ ret = gpiotools_request_line(device_name, lines, num_lines, config,
+ "gpio-event-mon");
+ if (ret < 0)
+ goto exit_device_close;
+ else
+ lfd = ret;
+
+ /* Read initial states */
+ values.mask = 0;
+ values.bits = 0;
+ for (i = 0; i < num_lines; i++)
+ gpiotools_set_bit(&values.mask, i);
+ ret = gpiotools_get_values(lfd, &values);
+ if (ret < 0) {
+ fprintf(stderr,
+ "Failed to issue GPIO LINE GET VALUES IOCTL (%d)\n",
+ ret);
+ goto exit_line_close;
+ }
+
+ if (num_lines == 1) {
+ fprintf(stdout, "Monitoring line %d on %s\n", lines[0], device_name);
+ fprintf(stdout, "Initial line value: %d\n",
+ gpiotools_test_bit(values.bits, 0));
+ } else {
+ fprintf(stdout, "Monitoring lines %d", lines[0]);
+ for (i = 1; i < num_lines - 1; i++)
+ fprintf(stdout, ", %d", lines[i]);
+ fprintf(stdout, " and %d on %s\n", lines[i], device_name);
+ fprintf(stdout, "Initial line values: %d",
+ gpiotools_test_bit(values.bits, 0));
+ for (i = 1; i < num_lines - 1; i++)
+ fprintf(stdout, ", %d",
+ gpiotools_test_bit(values.bits, i));
+ fprintf(stdout, " and %d\n",
+ gpiotools_test_bit(values.bits, i));
+ }
+
+ i = 0;
+ while (1) {
+ struct gpio_v2_line_event event;
+
+ ret = read(lfd, &event, sizeof(event));
+ if (ret == -1) {
+ if (errno == -EAGAIN) {
+ fprintf(stderr, "nothing available\n");
+ continue;
+ } else {
+ ret = -errno;
+ fprintf(stderr, "Failed to read event (%d)\n",
+ ret);
+ break;
+ }
+ }
+
+ if (ret != sizeof(event)) {
+ fprintf(stderr, "Reading event failed\n");
+ ret = -EIO;
+ break;
+ }
+ fprintf(stdout, "GPIO EVENT at %" PRIu64 " on line %d (%d|%d) ",
+ (uint64_t)event.timestamp_ns, event.offset, event.line_seqno,
+ event.seqno);
+ switch (event.id) {
+ case GPIO_V2_LINE_EVENT_RISING_EDGE:
+ fprintf(stdout, "rising edge");
+ break;
+ case GPIO_V2_LINE_EVENT_FALLING_EDGE:
+ fprintf(stdout, "falling edge");
+ break;
+ default:
+ fprintf(stdout, "unknown event");
+ }
+ fprintf(stdout, "\n");
+
+ i++;
+ if (i == loops)
+ break;
+ }
+
+exit_line_close:
+ if (close(lfd) == -1)
+ perror("Failed to close line file");
+exit_device_close:
+ if (close(cfd) == -1)
+ perror("Failed to close GPIO character device file");
+exit_free_name:
+ free(chrdev_name);
+ return ret;
+}
+
+void print_usage(void)
+{
+ fprintf(stderr, "Usage: gpio-event-mon [options]...\n"
+ "Listen to events on GPIO lines, 0->1 1->0\n"
+ " -n <name> Listen on GPIOs on a named device (must be stated)\n"
+ " -o <n> Offset of line to monitor (may be repeated)\n"
+ " -d Set line as open drain\n"
+ " -s Set line as open source\n"
+ " -r Listen for rising edges\n"
+ " -f Listen for falling edges\n"
+ " -w Report the wall-clock time for events\n"
+ " -t Report the hardware timestamp for events\n"
+ " -b <n> Debounce the line with period n microseconds\n"
+ " [-c <n>] Do <n> loops (optional, infinite loop if not stated)\n"
+ " -? This helptext\n"
+ "\n"
+ "Example:\n"
+ "gpio-event-mon -n gpiochip0 -o 4 -r -f -b 10000\n"
+ );
+}
+
+#define EDGE_FLAGS \
+ (GPIO_V2_LINE_FLAG_EDGE_RISING | \
+ GPIO_V2_LINE_FLAG_EDGE_FALLING)
+
+int main(int argc, char **argv)
+{
+ const char *device_name = NULL;
+ unsigned int lines[GPIO_V2_LINES_MAX];
+ unsigned int num_lines = 0;
+ unsigned int loops = 0;
+ struct gpio_v2_line_config config;
+ int c, attr, i;
+ unsigned long debounce_period_us = 0;
+
+ memset(&config, 0, sizeof(config));
+ config.flags = GPIO_V2_LINE_FLAG_INPUT;
+ while ((c = getopt(argc, argv, "c:n:o:b:dsrfwt?")) != -1) {
+ switch (c) {
+ case 'c':
+ loops = strtoul(optarg, NULL, 10);
+ break;
+ case 'n':
+ device_name = optarg;
+ break;
+ case 'o':
+ if (num_lines >= GPIO_V2_LINES_MAX) {
+ print_usage();
+ return -1;
+ }
+ lines[num_lines] = strtoul(optarg, NULL, 10);
+ num_lines++;
+ break;
+ case 'b':
+ debounce_period_us = strtoul(optarg, NULL, 10);
+ break;
+ case 'd':
+ config.flags |= GPIO_V2_LINE_FLAG_OPEN_DRAIN;
+ break;
+ case 's':
+ config.flags |= GPIO_V2_LINE_FLAG_OPEN_SOURCE;
+ break;
+ case 'r':
+ config.flags |= GPIO_V2_LINE_FLAG_EDGE_RISING;
+ break;
+ case 'f':
+ config.flags |= GPIO_V2_LINE_FLAG_EDGE_FALLING;
+ break;
+ case 'w':
+ config.flags |= GPIO_V2_LINE_FLAG_EVENT_CLOCK_REALTIME;
+ break;
+ case 't':
+ config.flags |= GPIO_V2_LINE_FLAG_EVENT_CLOCK_HTE;
+ break;
+ case '?':
+ print_usage();
+ return -1;
+ }
+ }
+
+ if (debounce_period_us) {
+ attr = config.num_attrs;
+ config.num_attrs++;
+ for (i = 0; i < num_lines; i++)
+ gpiotools_set_bit(&config.attrs[attr].mask, i);
+ config.attrs[attr].attr.id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE;
+ config.attrs[attr].attr.debounce_period_us = debounce_period_us;
+ }
+
+ if (!device_name || num_lines == 0) {
+ print_usage();
+ return -1;
+ }
+ if (!(config.flags & EDGE_FLAGS)) {
+ printf("No flags specified, listening on both rising and "
+ "falling edges\n");
+ config.flags |= EDGE_FLAGS;
+ }
+ return monitor_device(device_name, lines, num_lines, &config, loops);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 06:40:55 +0000