1 // SPDX-License-Identifier: GPL-2.0-only
3  * gpio-event-mon - monitor GPIO line events from userspace
8  *	gpio-event-mon -n <device-name> -o <offset>
26 #include "gpio-utils.h"
38 	int i = 0;  in monitor_device()
41 	if (ret < 0)  in monitor_device()
42 		return -ENOMEM;  in monitor_device()
44 	cfd = open(chrdev_name, 0);  in monitor_device()
45 	if (cfd == -1) {  in monitor_device()
46 		ret = -errno;  in monitor_device()
52 				     "gpio-event-mon");  in monitor_device()
53 	if (ret < 0)  in monitor_device()
59 	values.mask = 0;  in monitor_device()
60 	values.bits = 0;  in monitor_device()
61 	for (i = 0; i < num_lines; i++)  in monitor_device()
64 	if (ret < 0) {  in monitor_device()
72 		fprintf(stdout, "Monitoring line %d on %s\n", lines[0], device_name);  in monitor_device()
74 			gpiotools_test_bit(values.bits, 0));  in monitor_device()
76 		fprintf(stdout, "Monitoring lines %d", lines[0]);  in monitor_device()
77 		for (i = 1; i < num_lines - 1; i++)  in monitor_device()
81 			gpiotools_test_bit(values.bits, 0));  in monitor_device()
82 		for (i = 1; i < num_lines - 1; i++)  in monitor_device()
93 		if (ret == -1) {  in monitor_device()
94 			if (errno == -EAGAIN) {  in monitor_device()
98 				ret = -errno;  in monitor_device()
107 			ret = -EIO;  in monitor_device()
131 	if (close(lfd) == -1)  in monitor_device()
134 	if (close(cfd) == -1)  in monitor_device()
143 	fprintf(stderr, "Usage: gpio-event-mon [options]...\n"  in print_usage()
144 		"Listen to events on GPIO lines, 0->1 1->0\n"  in print_usage()
145 		"  -n <name>  Listen on GPIOs on a named device (must be stated)\n"  in print_usage()
146 		"  -o <n>     Offset of line to monitor (may be repeated)\n"  in print_usage()
147 		"  -d         Set line as open drain\n"  in print_usage()
148 		"  -s         Set line as open source\n"  in print_usage()
149 		"  -r         Listen for rising edges\n"  in print_usage()
150 		"  -f         Listen for falling edges\n"  in print_usage()
151 		"  -b <n>     Debounce the line with period n microseconds\n"  in print_usage()
152 		" [-c <n>]    Do <n> loops (optional, infinite loop if not stated)\n"  in print_usage()
153 		"  -?         This helptext\n"  in print_usage()
156 		"gpio-event-mon -n gpiochip0 -o 4 -r -f -b 10000\n"  in print_usage()
168 	unsigned int num_lines = 0;  in main()
169 	unsigned int loops = 0;  in main()
172 	unsigned long debounce_period_us = 0;  in main()
174 	memset(&config, 0, sizeof(config));  in main()
176 	while ((c = getopt(argc, argv, "c:n:o:b:dsrf?")) != -1) {  in main()
187 				return -1;  in main()
209 			return -1;  in main()
216 		for (i = 0; i < num_lines; i++)  in main()
222 	if (!device_name || num_lines == 0) {  in main()
224 		return -1;  in main()