Add a simple program that allows to read GPIO line names from the character device. This will be used in gpio-sim selftests.
Signed-off-by: Bartosz Golaszewski brgl@bgdev.pl --- tools/testing/selftests/gpio/.gitignore | 1 + tools/testing/selftests/gpio/Makefile | 2 +- tools/testing/selftests/gpio/gpio-line-name.c | 55 +++++++++++++++++++ 3 files changed, 57 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/gpio/gpio-line-name.c
diff --git a/tools/testing/selftests/gpio/.gitignore b/tools/testing/selftests/gpio/.gitignore index 4ea4f58dab1a..ededb077a3a6 100644 --- a/tools/testing/selftests/gpio/.gitignore +++ b/tools/testing/selftests/gpio/.gitignore @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only gpio-mockup-cdev gpio-chip-info +gpio-line-name diff --git a/tools/testing/selftests/gpio/Makefile b/tools/testing/selftests/gpio/Makefile index 84b48547f94c..d7d8f1985d99 100644 --- a/tools/testing/selftests/gpio/Makefile +++ b/tools/testing/selftests/gpio/Makefile @@ -2,6 +2,6 @@
TEST_PROGS := gpio-mockup.sh TEST_FILES := gpio-mockup-sysfs.sh -TEST_GEN_PROGS_EXTENDED := gpio-mockup-cdev gpio-chip-info +TEST_GEN_PROGS_EXTENDED := gpio-mockup-cdev gpio-chip-info gpio-line-name
include ../lib.mk diff --git a/tools/testing/selftests/gpio/gpio-line-name.c b/tools/testing/selftests/gpio/gpio-line-name.c new file mode 100644 index 000000000000..e635cfadbded --- /dev/null +++ b/tools/testing/selftests/gpio/gpio-line-name.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * GPIO character device helper for reading line names. + * + * Copyright (C) 2021 Bartosz Golaszewski brgl@bgdev.pl + */ + +#include <fcntl.h> +#include <linux/gpio.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/types.h> + +static void print_usage(void) +{ + printf("usage:\n"); + printf(" gpio-line-name <chip path> <line offset>\n"); +} + +int main(int argc, char **argv) +{ + struct gpio_v2_line_info info; + int fd, ret; + char *endp; + + if (argc != 3) { + print_usage(); + return EXIT_FAILURE; + } + + fd = open(argv[1], O_RDWR); + if (fd < 0) { + perror("unable to open the GPIO chip"); + return EXIT_FAILURE; + } + + memset(&info, 0, sizeof(info)); + info.offset = strtoul(argv[2], &endp, 10); + if (*endp != '\0') { + print_usage(); + return EXIT_FAILURE; + } + + ret = ioctl(fd, GPIO_V2_GET_LINEINFO_IOCTL, &info); + if (ret) { + perror("line info ioctl failed"); + return EXIT_FAILURE; + } + + printf("%s\n", info.name); + + return EXIT_SUCCESS; +}