1 // SPDX-License-Identifier: GPL-2.0-only
3  * gpio-hammer - example swiss army knife to shake GPIO lines on a system
8  *	gpio-hammer -n <device-name> -o <offset1> -o <offset2>
23 #include "gpio-utils.h"
25 int hammer_device(const char *device_name, unsigned int *lines, int num_lines,  in hammer_device()  argument
30 	char swirr[] = "-\\|/";  in hammer_device()
39 	ret = gpiotools_request_line(device_name, lines, num_lines,  in hammer_device()
40 				     &config, "gpio-hammer");  in hammer_device()
55 	fprintf(stdout, "Hammer lines [");  in hammer_device()
57 		fprintf(stdout, "%d", lines[i]);  in hammer_device()
58 		if (i != (num_lines - 1))  in hammer_device()
61 	fprintf(stdout, "] on %s, initial states: [", device_name);  in hammer_device()
64 		if (i != (num_lines - 1))  in hammer_device()
72 		/* Invert all lines so we blink */  in hammer_device()
80 		/* Re-read values to get status */  in hammer_device()
87 		if (j == sizeof(swirr) - 1)  in hammer_device()
92 			fprintf(stdout, "%d: %d", lines[i],  in hammer_device()
94 			if (i != (num_lines - 1))  in hammer_device()
115 	fprintf(stderr, "Usage: gpio-hammer [options]...\n"  in print_usage()
116 		"Hammer GPIO lines, 0->1->0->1...\n"  in print_usage()
117 		"  -n <name>  Hammer GPIOs on a named device (must be stated)\n"  in print_usage()
118 		"  -o <n>     Offset[s] to hammer, at least one, several can be stated\n"  in print_usage()
119 		" [-c <n>]    Do <n> loops (optional, infinite loop if not stated)\n"  in print_usage()
120 		"  -?         This helptext\n"  in print_usage()
123 		"gpio-hammer -n gpiochip0 -o 4\n"  in print_usage()
130 	unsigned int lines[GPIOHANDLES_MAX];  in main()  local
137 	while ((c = getopt(argc, argv, "c:n:o:?")) != -1) {  in main()
149 			 * '-o' was given to give an accurate error message  in main()
152 				lines[i] = strtoul(optarg, NULL, 10);  in main()
158 			return -1;  in main()
164 			"Only %d occurrences of '-o' are allowed, %d were found\n",  in main()
166 		return -1;  in main()
173 		return -1;  in main()
175 	return hammer_device(device_name, lines, num_lines, loops);  in main()