v4.19.13 snapshot.
diff --git a/tools/gpio/.gitignore b/tools/gpio/.gitignore
new file mode 100644
index 0000000..9e9dd4b
--- /dev/null
+++ b/tools/gpio/.gitignore
@@ -0,0 +1,4 @@
+gpio-event-mon
+gpio-hammer
+lsgpio
+
diff --git a/tools/gpio/Build b/tools/gpio/Build
new file mode 100644
index 0000000..620c193
--- /dev/null
+++ b/tools/gpio/Build
@@ -0,0 +1,3 @@
+lsgpio-y += lsgpio.o gpio-utils.o
+gpio-hammer-y += gpio-hammer.o gpio-utils.o
+gpio-event-mon-y += gpio-event-mon.o gpio-utils.o
diff --git a/tools/gpio/Makefile b/tools/gpio/Makefile
new file mode 100644
index 0000000..240eda0
--- /dev/null
+++ b/tools/gpio/Makefile
@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: GPL-2.0
+include ../scripts/Makefile.include
+
+bindir ?= /usr/bin
+
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(CURDIR)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+endif
+
+# Do not use make's built-in rules
+# (this improves performance and avoids hard-to-debug behaviour);
+MAKEFLAGS += -r
+
+CFLAGS += -O2 -Wall -g -D_GNU_SOURCE -I$(OUTPUT)include
+
+ALL_TARGETS := lsgpio gpio-hammer gpio-event-mon
+ALL_PROGRAMS := $(patsubst %,$(OUTPUT)%,$(ALL_TARGETS))
+
+all: $(ALL_PROGRAMS)
+
+export srctree OUTPUT CC LD CFLAGS
+include $(srctree)/tools/build/Makefile.include
+
+#
+# We need the following to be outside of kernel tree
+#
+$(OUTPUT)include/linux/gpio.h: ../../include/uapi/linux/gpio.h
+ mkdir -p $(OUTPUT)include/linux 2>&1 || true
+ ln -sf $(CURDIR)/../../include/uapi/linux/gpio.h $@
+
+prepare: $(OUTPUT)include/linux/gpio.h
+
+#
+# lsgpio
+#
+LSGPIO_IN := $(OUTPUT)lsgpio-in.o
+$(LSGPIO_IN): prepare FORCE
+ $(Q)$(MAKE) $(build)=lsgpio
+$(OUTPUT)lsgpio: $(LSGPIO_IN)
+ $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+
+#
+# gpio-hammer
+#
+GPIO_HAMMER_IN := $(OUTPUT)gpio-hammer-in.o
+$(GPIO_HAMMER_IN): prepare FORCE
+ $(Q)$(MAKE) $(build)=gpio-hammer
+$(OUTPUT)gpio-hammer: $(GPIO_HAMMER_IN)
+ $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+
+#
+# gpio-event-mon
+#
+GPIO_EVENT_MON_IN := $(OUTPUT)gpio-event-mon-in.o
+$(GPIO_EVENT_MON_IN): prepare FORCE
+ $(Q)$(MAKE) $(build)=gpio-event-mon
+$(OUTPUT)gpio-event-mon: $(GPIO_EVENT_MON_IN)
+ $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+
+clean:
+ rm -f $(ALL_PROGRAMS)
+ rm -f $(OUTPUT)include/linux/gpio.h
+ find $(if $(OUTPUT),$(OUTPUT),.) -name '*.o' -delete -o -name '\.*.d' -delete
+
+install: $(ALL_PROGRAMS)
+ install -d -m 755 $(DESTDIR)$(bindir); \
+ for program in $(ALL_PROGRAMS); do \
+ install $$program $(DESTDIR)$(bindir); \
+ done
+
+FORCE:
+
+.PHONY: all install clean FORCE prepare
diff --git a/tools/gpio/gpio-event-mon.c b/tools/gpio/gpio-event-mon.c
new file mode 100644
index 0000000..c864544
--- /dev/null
+++ b/tools/gpio/gpio-event-mon.c
@@ -0,0 +1,194 @@
+/*
+ * gpio-event-mon - monitor GPIO line events from userspace
+ *
+ * Copyright (C) 2016 Linus Walleij
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * 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>
+
+int monitor_device(const char *device_name,
+ unsigned int line,
+ uint32_t handleflags,
+ uint32_t eventflags,
+ unsigned int loops)
+{
+ struct gpioevent_request req;
+ struct gpiohandle_data data;
+ char *chrdev_name;
+ int fd;
+ int ret;
+ int i = 0;
+
+ ret = asprintf(&chrdev_name, "/dev/%s", device_name);
+ if (ret < 0)
+ return -ENOMEM;
+
+ fd = open(chrdev_name, 0);
+ if (fd == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to open %s\n", chrdev_name);
+ goto exit_close_error;
+ }
+
+ req.lineoffset = line;
+ req.handleflags = handleflags;
+ req.eventflags = eventflags;
+ strcpy(req.consumer_label, "gpio-event-mon");
+
+ ret = ioctl(fd, GPIO_GET_LINEEVENT_IOCTL, &req);
+ if (ret == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to issue GET EVENT "
+ "IOCTL (%d)\n",
+ ret);
+ goto exit_close_error;
+ }
+
+ /* Read initial states */
+ ret = ioctl(req.fd, GPIOHANDLE_GET_LINE_VALUES_IOCTL, &data);
+ if (ret == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to issue GPIOHANDLE GET LINE "
+ "VALUES IOCTL (%d)\n",
+ ret);
+ goto exit_close_error;
+ }
+
+ fprintf(stdout, "Monitoring line %d on %s\n", line, device_name);
+ fprintf(stdout, "Initial line value: %d\n", data.values[0]);
+
+ while (1) {
+ struct gpioevent_data event;
+
+ ret = read(req.fd, &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 %llu: ", event.timestamp);
+ switch (event.id) {
+ case GPIOEVENT_EVENT_RISING_EDGE:
+ fprintf(stdout, "rising edge");
+ break;
+ case GPIOEVENT_EVENT_FALLING_EDGE:
+ fprintf(stdout, "falling edge");
+ break;
+ default:
+ fprintf(stdout, "unknown event");
+ }
+ fprintf(stdout, "\n");
+
+ i++;
+ if (i == loops)
+ break;
+ }
+
+exit_close_error:
+ if (close(fd) == -1)
+ perror("Failed to close GPIO character device file");
+ 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 to monitor\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"
+ " [-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\n"
+ );
+}
+
+int main(int argc, char **argv)
+{
+ const char *device_name = NULL;
+ unsigned int line = -1;
+ unsigned int loops = 0;
+ uint32_t handleflags = GPIOHANDLE_REQUEST_INPUT;
+ uint32_t eventflags = 0;
+ int c;
+
+ while ((c = getopt(argc, argv, "c:n:o:dsrf?")) != -1) {
+ switch (c) {
+ case 'c':
+ loops = strtoul(optarg, NULL, 10);
+ break;
+ case 'n':
+ device_name = optarg;
+ break;
+ case 'o':
+ line = strtoul(optarg, NULL, 10);
+ break;
+ case 'd':
+ handleflags |= GPIOHANDLE_REQUEST_OPEN_DRAIN;
+ break;
+ case 's':
+ handleflags |= GPIOHANDLE_REQUEST_OPEN_SOURCE;
+ break;
+ case 'r':
+ eventflags |= GPIOEVENT_REQUEST_RISING_EDGE;
+ break;
+ case 'f':
+ eventflags |= GPIOEVENT_REQUEST_FALLING_EDGE;
+ break;
+ case '?':
+ print_usage();
+ return -1;
+ }
+ }
+
+ if (!device_name || line == -1) {
+ print_usage();
+ return -1;
+ }
+ if (!eventflags) {
+ printf("No flags specified, listening on both rising and "
+ "falling edges\n");
+ eventflags = GPIOEVENT_REQUEST_BOTH_EDGES;
+ }
+ return monitor_device(device_name, line, handleflags,
+ eventflags, loops);
+}
diff --git a/tools/gpio/gpio-hammer.c b/tools/gpio/gpio-hammer.c
new file mode 100644
index 0000000..4bcb234
--- /dev/null
+++ b/tools/gpio/gpio-hammer.c
@@ -0,0 +1,156 @@
+/*
+ * gpio-hammer - example swiss army knife to shake GPIO lines on a system
+ *
+ * Copyright (C) 2016 Linus Walleij
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * Usage:
+ * gpio-hammer -n <device-name> -o <offset1> -o <offset2>
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <dirent.h>
+#include <errno.h>
+#include <string.h>
+#include <poll.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <sys/ioctl.h>
+#include <linux/gpio.h>
+#include "gpio-utils.h"
+
+int hammer_device(const char *device_name, unsigned int *lines, int nlines,
+ unsigned int loops)
+{
+ struct gpiohandle_data data;
+ char swirr[] = "-\\|/";
+ int fd;
+ int ret;
+ int i, j;
+ unsigned int iteration = 0;
+
+ memset(&data.values, 0, sizeof(data.values));
+ ret = gpiotools_request_linehandle(device_name, lines, nlines,
+ GPIOHANDLE_REQUEST_OUTPUT, &data,
+ "gpio-hammer");
+ if (ret < 0)
+ goto exit_error;
+ else
+ fd = ret;
+
+ ret = gpiotools_get_values(fd, &data);
+ if (ret < 0)
+ goto exit_close_error;
+
+ fprintf(stdout, "Hammer lines [");
+ for (i = 0; i < nlines; i++) {
+ fprintf(stdout, "%d", lines[i]);
+ if (i != (nlines - 1))
+ fprintf(stdout, ", ");
+ }
+ fprintf(stdout, "] on %s, initial states: [", device_name);
+ for (i = 0; i < nlines; i++) {
+ fprintf(stdout, "%d", data.values[i]);
+ if (i != (nlines - 1))
+ fprintf(stdout, ", ");
+ }
+ fprintf(stdout, "]\n");
+
+ /* Hammertime! */
+ j = 0;
+ while (1) {
+ /* Invert all lines so we blink */
+ for (i = 0; i < nlines; i++)
+ data.values[i] = !data.values[i];
+
+ ret = gpiotools_set_values(fd, &data);
+ if (ret < 0)
+ goto exit_close_error;
+
+ /* Re-read values to get status */
+ ret = gpiotools_get_values(fd, &data);
+ if (ret < 0)
+ goto exit_close_error;
+
+ fprintf(stdout, "[%c] ", swirr[j]);
+ j++;
+ if (j == sizeof(swirr)-1)
+ j = 0;
+
+ fprintf(stdout, "[");
+ for (i = 0; i < nlines; i++) {
+ fprintf(stdout, "%d: %d", lines[i], data.values[i]);
+ if (i != (nlines - 1))
+ fprintf(stdout, ", ");
+ }
+ fprintf(stdout, "]\r");
+ fflush(stdout);
+ sleep(1);
+ iteration++;
+ if (loops && iteration == loops)
+ break;
+ }
+ fprintf(stdout, "\n");
+ ret = 0;
+
+exit_close_error:
+ gpiotools_release_linehandle(fd);
+exit_error:
+ return ret;
+}
+
+void print_usage(void)
+{
+ fprintf(stderr, "Usage: gpio-hammer [options]...\n"
+ "Hammer GPIO lines, 0->1->0->1...\n"
+ " -n <name> Hammer GPIOs on a named device (must be stated)\n"
+ " -o <n> Offset[s] to hammer, at least one, several can be stated\n"
+ " [-c <n>] Do <n> loops (optional, infinite loop if not stated)\n"
+ " -? This helptext\n"
+ "\n"
+ "Example:\n"
+ "gpio-hammer -n gpiochip0 -o 4\n"
+ );
+}
+
+int main(int argc, char **argv)
+{
+ const char *device_name = NULL;
+ unsigned int lines[GPIOHANDLES_MAX];
+ unsigned int loops = 0;
+ int nlines;
+ int c;
+ int i;
+
+ i = 0;
+ while ((c = getopt(argc, argv, "c:n:o:?")) != -1) {
+ switch (c) {
+ case 'c':
+ loops = strtoul(optarg, NULL, 10);
+ break;
+ case 'n':
+ device_name = optarg;
+ break;
+ case 'o':
+ lines[i] = strtoul(optarg, NULL, 10);
+ i++;
+ break;
+ case '?':
+ print_usage();
+ return -1;
+ }
+ }
+ nlines = i;
+
+ if (!device_name || !nlines) {
+ print_usage();
+ return -1;
+ }
+ return hammer_device(device_name, lines, nlines, loops);
+}
diff --git a/tools/gpio/gpio-utils.c b/tools/gpio/gpio-utils.c
new file mode 100644
index 0000000..cf7e2f3
--- /dev/null
+++ b/tools/gpio/gpio-utils.c
@@ -0,0 +1,270 @@
+/*
+ * GPIO tools - helpers library for the GPIO tools
+ *
+ * Copyright (C) 2015 Linus Walleij
+ * Copyright (C) 2016 Bamvor Jian Zhang
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <sys/ioctl.h>
+#include <linux/gpio.h>
+#include "gpio-utils.h"
+
+#define COMSUMER "gpio-utils"
+
+/**
+ * doc: Operation of gpio
+ *
+ * Provide the api of gpiochip for chardev interface. There are two
+ * types of api. The first one provide as same function as each
+ * ioctl, including request and release for lines of gpio, read/write
+ * the value of gpio. If the user want to do lots of read and write of
+ * lines of gpio, user should use this type of api.
+ *
+ * The second one provide the easy to use api for user. Each of the
+ * following api will request gpio lines, do the operation and then
+ * release these lines.
+ */
+/**
+ * gpiotools_request_linehandle() - request gpio lines in a gpiochip
+ * @device_name: The name of gpiochip without prefix "/dev/",
+ * such as "gpiochip0"
+ * @lines: An array desired lines, specified by offset
+ * index for the associated GPIO device.
+ * @nline: The number of lines to request.
+ * @flag: The new flag for requsted gpio. Reference
+ * "linux/gpio.h" for the meaning of flag.
+ * @data: Default value will be set to gpio when flag is
+ * GPIOHANDLE_REQUEST_OUTPUT.
+ * @consumer_label: The name of consumer, such as "sysfs",
+ * "powerkey". This is useful for other users to
+ * know who is using.
+ *
+ * Request gpio lines through the ioctl provided by chardev. User
+ * could call gpiotools_set_values() and gpiotools_get_values() to
+ * read and write respectively through the returned fd. Call
+ * gpiotools_release_linehandle() to release these lines after that.
+ *
+ * Return: On success return the fd;
+ * On failure return the errno.
+ */
+int gpiotools_request_linehandle(const char *device_name, unsigned int *lines,
+ unsigned int nlines, unsigned int flag,
+ struct gpiohandle_data *data,
+ const char *consumer_label)
+{
+ struct gpiohandle_request req;
+ char *chrdev_name;
+ int fd;
+ int i;
+ int ret;
+
+ ret = asprintf(&chrdev_name, "/dev/%s", device_name);
+ if (ret < 0)
+ return -ENOMEM;
+
+ fd = open(chrdev_name, 0);
+ if (fd == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to open %s, %s\n",
+ chrdev_name, strerror(errno));
+ goto exit_close_error;
+ }
+
+ for (i = 0; i < nlines; i++)
+ req.lineoffsets[i] = lines[i];
+
+ req.flags = flag;
+ strcpy(req.consumer_label, consumer_label);
+ req.lines = nlines;
+ if (flag & GPIOHANDLE_REQUEST_OUTPUT)
+ memcpy(req.default_values, data, sizeof(req.default_values));
+
+ ret = ioctl(fd, GPIO_GET_LINEHANDLE_IOCTL, &req);
+ if (ret == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to issue %s (%d), %s\n",
+ "GPIO_GET_LINEHANDLE_IOCTL", ret, strerror(errno));
+ }
+
+exit_close_error:
+ if (close(fd) == -1)
+ perror("Failed to close GPIO character device file");
+ free(chrdev_name);
+ return ret < 0 ? ret : req.fd;
+}
+/**
+ * gpiotools_set_values(): Set the value of gpio(s)
+ * @fd: The fd returned by
+ * gpiotools_request_linehandle().
+ * @data: The array of values want to set.
+ *
+ * Return: On success return 0;
+ * On failure return the errno.
+ */
+int gpiotools_set_values(const int fd, struct gpiohandle_data *data)
+{
+ int ret;
+
+ ret = ioctl(fd, GPIOHANDLE_SET_LINE_VALUES_IOCTL, data);
+ if (ret == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to issue %s (%d), %s\n",
+ "GPIOHANDLE_SET_LINE_VALUES_IOCTL", ret,
+ strerror(errno));
+ }
+
+ return ret;
+}
+
+/**
+ * gpiotools_get_values(): Get the value of gpio(s)
+ * @fd: The fd returned by
+ * gpiotools_request_linehandle().
+ * @data: The array of values get from hardware.
+ *
+ * Return: On success return 0;
+ * On failure return the errno.
+ */
+int gpiotools_get_values(const int fd, struct gpiohandle_data *data)
+{
+ int ret;
+
+ ret = ioctl(fd, GPIOHANDLE_GET_LINE_VALUES_IOCTL, data);
+ if (ret == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to issue %s (%d), %s\n",
+ "GPIOHANDLE_GET_LINE_VALUES_IOCTL", ret,
+ strerror(errno));
+ }
+
+ return ret;
+}
+
+/**
+ * gpiotools_release_linehandle(): Release the line(s) of gpiochip
+ * @fd: The fd returned by
+ * gpiotools_request_linehandle().
+ *
+ * Return: On success return 0;
+ * On failure return the errno.
+ */
+int gpiotools_release_linehandle(const int fd)
+{
+ int ret;
+
+ ret = close(fd);
+ if (ret == -1) {
+ perror("Failed to close GPIO LINEHANDLE device file");
+ ret = -errno;
+ }
+
+ return ret;
+}
+
+/**
+ * gpiotools_get(): Get value from specific line
+ * @device_name: The name of gpiochip without prefix "/dev/",
+ * such as "gpiochip0"
+ * @line: number of line, such as 2.
+ *
+ * Return: On success return 0;
+ * On failure return the errno.
+ */
+int gpiotools_get(const char *device_name, unsigned int line)
+{
+ struct gpiohandle_data data;
+ unsigned int lines[] = {line};
+
+ gpiotools_gets(device_name, lines, 1, &data);
+ return data.values[0];
+}
+
+
+/**
+ * gpiotools_gets(): Get values from specific lines.
+ * @device_name: The name of gpiochip without prefix "/dev/",
+ * such as "gpiochip0".
+ * @lines: An array desired lines, specified by offset
+ * index for the associated GPIO device.
+ * @nline: The number of lines to request.
+ * @data: The array of values get from gpiochip.
+ *
+ * Return: On success return 0;
+ * On failure return the errno.
+ */
+int gpiotools_gets(const char *device_name, unsigned int *lines,
+ unsigned int nlines, struct gpiohandle_data *data)
+{
+ int fd;
+ int ret;
+ int ret_close;
+
+ ret = gpiotools_request_linehandle(device_name, lines, nlines,
+ GPIOHANDLE_REQUEST_INPUT, data,
+ COMSUMER);
+ if (ret < 0)
+ return ret;
+
+ fd = ret;
+ ret = gpiotools_get_values(fd, data);
+ ret_close = gpiotools_release_linehandle(fd);
+ return ret < 0 ? ret : ret_close;
+}
+
+/**
+ * gpiotools_set(): Set value to specific line
+ * @device_name: The name of gpiochip without prefix "/dev/",
+ * such as "gpiochip0"
+ * @line: number of line, such as 2.
+ * @value: The value of gpio, must be 0(low) or 1(high).
+ *
+ * Return: On success return 0;
+ * On failure return the errno.
+ */
+int gpiotools_set(const char *device_name, unsigned int line,
+ unsigned int value)
+{
+ struct gpiohandle_data data;
+ unsigned int lines[] = {line};
+
+ data.values[0] = value;
+ return gpiotools_sets(device_name, lines, 1, &data);
+}
+
+/**
+ * gpiotools_sets(): Set values to specific lines.
+ * @device_name: The name of gpiochip without prefix "/dev/",
+ * such as "gpiochip0".
+ * @lines: An array desired lines, specified by offset
+ * index for the associated GPIO device.
+ * @nline: The number of lines to request.
+ * @data: The array of values set to gpiochip, must be
+ * 0(low) or 1(high).
+ *
+ * Return: On success return 0;
+ * On failure return the errno.
+ */
+int gpiotools_sets(const char *device_name, unsigned int *lines,
+ unsigned int nlines, struct gpiohandle_data *data)
+{
+ int ret;
+
+ ret = gpiotools_request_linehandle(device_name, lines, nlines,
+ GPIOHANDLE_REQUEST_OUTPUT, data,
+ COMSUMER);
+ if (ret < 0)
+ return ret;
+
+ return gpiotools_release_linehandle(ret);
+}
diff --git a/tools/gpio/gpio-utils.h b/tools/gpio/gpio-utils.h
new file mode 100644
index 0000000..344ea04
--- /dev/null
+++ b/tools/gpio/gpio-utils.h
@@ -0,0 +1,43 @@
+/*
+ * GPIO tools - utility helpers library for the GPIO tools
+ *
+ * Copyright (C) 2015 Linus Walleij
+ *
+ * Portions copied from iio_utils and lssio:
+ * Copyright (c) 2010 Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
+ * Copyright (c) 2008 Jonathan Cameron
+ * *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+#ifndef _GPIO_UTILS_H_
+#define _GPIO_UTILS_H_
+
+#include <string.h>
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+static inline int check_prefix(const char *str, const char *prefix)
+{
+ return strlen(str) > strlen(prefix) &&
+ strncmp(str, prefix, strlen(prefix)) == 0;
+}
+
+int gpiotools_request_linehandle(const char *device_name, unsigned int *lines,
+ unsigned int nlines, unsigned int flag,
+ struct gpiohandle_data *data,
+ const char *consumer_label);
+int gpiotools_set_values(const int fd, struct gpiohandle_data *data);
+int gpiotools_get_values(const int fd, struct gpiohandle_data *data);
+int gpiotools_release_linehandle(const int fd);
+
+int gpiotools_get(const char *device_name, unsigned int line);
+int gpiotools_gets(const char *device_name, unsigned int *lines,
+ unsigned int nlines, struct gpiohandle_data *data);
+int gpiotools_set(const char *device_name, unsigned int line,
+ unsigned int value);
+int gpiotools_sets(const char *device_name, unsigned int *lines,
+ unsigned int nlines, struct gpiohandle_data *data);
+
+#endif /* _GPIO_UTILS_H_ */
diff --git a/tools/gpio/lsgpio.c b/tools/gpio/lsgpio.c
new file mode 100644
index 0000000..eb3f56e
--- /dev/null
+++ b/tools/gpio/lsgpio.c
@@ -0,0 +1,195 @@
+/*
+ * lsgpio - example on how to list the GPIO lines on a system
+ *
+ * Copyright (C) 2015 Linus Walleij
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * Usage:
+ * lsgpio <-n device-name>
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <dirent.h>
+#include <errno.h>
+#include <string.h>
+#include <poll.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <sys/ioctl.h>
+#include <linux/gpio.h>
+
+#include "gpio-utils.h"
+
+struct gpio_flag {
+ char *name;
+ unsigned long mask;
+};
+
+struct gpio_flag flagnames[] = {
+ {
+ .name = "kernel",
+ .mask = GPIOLINE_FLAG_KERNEL,
+ },
+ {
+ .name = "output",
+ .mask = GPIOLINE_FLAG_IS_OUT,
+ },
+ {
+ .name = "active-low",
+ .mask = GPIOLINE_FLAG_ACTIVE_LOW,
+ },
+ {
+ .name = "open-drain",
+ .mask = GPIOLINE_FLAG_OPEN_DRAIN,
+ },
+ {
+ .name = "open-source",
+ .mask = GPIOLINE_FLAG_OPEN_SOURCE,
+ },
+};
+
+void print_flags(unsigned long flags)
+{
+ int i;
+ int printed = 0;
+
+ for (i = 0; i < ARRAY_SIZE(flagnames); i++) {
+ if (flags & flagnames[i].mask) {
+ if (printed)
+ fprintf(stdout, " ");
+ fprintf(stdout, "%s", flagnames[i].name);
+ printed++;
+ }
+ }
+}
+
+int list_device(const char *device_name)
+{
+ struct gpiochip_info cinfo;
+ char *chrdev_name;
+ int fd;
+ int ret;
+ int i;
+
+ ret = asprintf(&chrdev_name, "/dev/%s", device_name);
+ if (ret < 0)
+ return -ENOMEM;
+
+ fd = open(chrdev_name, 0);
+ if (fd == -1) {
+ ret = -errno;
+ fprintf(stderr, "Failed to open %s\n", chrdev_name);
+ goto exit_close_error;
+ }
+
+ /* Inspect this GPIO chip */
+ ret = ioctl(fd, GPIO_GET_CHIPINFO_IOCTL, &cinfo);
+ if (ret == -1) {
+ ret = -errno;
+ perror("Failed to issue CHIPINFO IOCTL\n");
+ goto exit_close_error;
+ }
+ fprintf(stdout, "GPIO chip: %s, \"%s\", %u GPIO lines\n",
+ cinfo.name, cinfo.label, cinfo.lines);
+
+ /* Loop over the lines and print info */
+ for (i = 0; i < cinfo.lines; i++) {
+ struct gpioline_info linfo;
+
+ memset(&linfo, 0, sizeof(linfo));
+ linfo.line_offset = i;
+
+ ret = ioctl(fd, GPIO_GET_LINEINFO_IOCTL, &linfo);
+ if (ret == -1) {
+ ret = -errno;
+ perror("Failed to issue LINEINFO IOCTL\n");
+ goto exit_close_error;
+ }
+ fprintf(stdout, "\tline %2d:", linfo.line_offset);
+ if (linfo.name[0])
+ fprintf(stdout, " \"%s\"", linfo.name);
+ else
+ fprintf(stdout, " unnamed");
+ if (linfo.consumer[0])
+ fprintf(stdout, " \"%s\"", linfo.consumer);
+ else
+ fprintf(stdout, " unused");
+ if (linfo.flags) {
+ fprintf(stdout, " [");
+ print_flags(linfo.flags);
+ fprintf(stdout, "]");
+ }
+ fprintf(stdout, "\n");
+
+ }
+
+exit_close_error:
+ if (close(fd) == -1)
+ perror("Failed to close GPIO character device file");
+ free(chrdev_name);
+ return ret;
+}
+
+void print_usage(void)
+{
+ fprintf(stderr, "Usage: lsgpio [options]...\n"
+ "List GPIO chips, lines and states\n"
+ " -n <name> List GPIOs on a named device\n"
+ " -? This helptext\n"
+ );
+}
+
+int main(int argc, char **argv)
+{
+ const char *device_name = NULL;
+ int ret;
+ int c;
+
+ while ((c = getopt(argc, argv, "n:")) != -1) {
+ switch (c) {
+ case 'n':
+ device_name = optarg;
+ break;
+ case '?':
+ print_usage();
+ return -1;
+ }
+ }
+
+ if (device_name)
+ ret = list_device(device_name);
+ else {
+ const struct dirent *ent;
+ DIR *dp;
+
+ /* List all GPIO devices one at a time */
+ dp = opendir("/dev");
+ if (!dp) {
+ ret = -errno;
+ goto error_out;
+ }
+
+ ret = -ENOENT;
+ while (ent = readdir(dp), ent) {
+ if (check_prefix(ent->d_name, "gpiochip")) {
+ ret = list_device(ent->d_name);
+ if (ret)
+ break;
+ }
+ }
+
+ ret = 0;
+ if (closedir(dp) == -1) {
+ perror("scanning devices: Failed to close directory");
+ ret = -errno;
+ }
+ }
+error_out:
+ return ret;
+}