diff options
Diffstat (limited to 'tools/testing/selftests/gpio/gpio-mockup-cdev.c')
-rw-r--r-- | tools/testing/selftests/gpio/gpio-mockup-cdev.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/tools/testing/selftests/gpio/gpio-mockup-cdev.c b/tools/testing/selftests/gpio/gpio-mockup-cdev.c new file mode 100644 index 000000000000..3a7fc3ac1349 --- /dev/null +++ b/tools/testing/selftests/gpio/gpio-mockup-cdev.c @@ -0,0 +1,139 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * GPIO mockup cdev test helper + * + * Copyright (C) 2020 Kent Gibson + */ + +#include <errno.h> +#include <fcntl.h> +#include <signal.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/ioctl.h> +#include <linux/gpio.h> + +#define CONSUMER "gpio-mockup-cdev" + +static int request_line_v1(int cfd, unsigned int offset, + uint32_t flags, unsigned int val) +{ + struct gpiohandle_request req; + int ret; + + memset(&req, 0, sizeof(req)); + req.lines = 1; + req.lineoffsets[0] = offset; + req.flags = flags; + strcpy(req.consumer_label, CONSUMER); + if (flags & GPIOHANDLE_REQUEST_OUTPUT) + req.default_values[0] = val; + + ret = ioctl(cfd, GPIO_GET_LINEHANDLE_IOCTL, &req); + if (ret == -1) + return -errno; + return req.fd; +} + +static int get_value_v1(int lfd) +{ + struct gpiohandle_data vals; + int ret; + + memset(&vals, 0, sizeof(vals)); + ret = ioctl(lfd, GPIOHANDLE_GET_LINE_VALUES_IOCTL, &vals); + if (ret == -1) + return -errno; + return vals.values[0]; +} + +static void usage(char *prog) +{ + printf("Usage: %s [-l] [-b <bias>] [-s <value>] [-u <uAPI>] <gpiochip> <offset>\n", prog); + printf(" -b: set line bias to one of pull-down, pull-up, disabled\n"); + printf(" (default is to leave bias unchanged):\n"); + printf(" -l: set line active low (default is active high)\n"); + printf(" -s: set line value (default is to get line value)\n"); + exit(-1); +} + +static int wait_signal(void) +{ + int sig; + sigset_t wset; + + sigemptyset(&wset); + sigaddset(&wset, SIGHUP); + sigaddset(&wset, SIGINT); + sigaddset(&wset, SIGTERM); + sigwait(&wset, &sig); + + return sig; +} + +int main(int argc, char *argv[]) +{ + char *chip; + int opt, ret, cfd, lfd; + unsigned int offset, val; + uint32_t flags_v1; + + ret = 0; + flags_v1 = GPIOHANDLE_REQUEST_INPUT; + + while ((opt = getopt(argc, argv, "lb:s:u:")) != -1) { + switch (opt) { + case 'l': + flags_v1 |= GPIOHANDLE_REQUEST_ACTIVE_LOW; + break; + case 'b': + if (strcmp("pull-up", optarg) == 0) + flags_v1 |= GPIOHANDLE_REQUEST_BIAS_PULL_UP; + else if (strcmp("pull-down", optarg) == 0) + flags_v1 |= GPIOHANDLE_REQUEST_BIAS_PULL_DOWN; + else if (strcmp("disabled", optarg) == 0) + flags_v1 |= GPIOHANDLE_REQUEST_BIAS_DISABLE; + break; + case 's': + val = atoi(optarg); + flags_v1 &= ~GPIOHANDLE_REQUEST_INPUT; + flags_v1 |= GPIOHANDLE_REQUEST_OUTPUT; + break; + default: + usage(argv[0]); + } + } + + if (argc < optind + 2) + usage(argv[0]); + + chip = argv[optind]; + offset = atoi(argv[optind + 1]); + + cfd = open(chip, 0); + if (cfd == -1) { + fprintf(stderr, "Failed to open %s: %s\n", chip, strerror(errno)); + return -errno; + } + + lfd = request_line_v1(cfd, offset, flags_v1, val); + + close(cfd); + + if (lfd < 0) { + fprintf(stderr, "Failed to request %s:%d: %s\n", chip, offset, strerror(-lfd)); + return lfd; + } + + if (flags_v1 & GPIOHANDLE_REQUEST_OUTPUT) + wait_signal(); + else + ret = get_value_v1(lfd); + + close(lfd); + + return ret; +} |