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@enh
Created February 22, 2022 01:08
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Initial toybox gpiod implementation.
/* gpiod.c - gpio tools
*
* Copyright 2021 The Android Open Source Project
*
* TODO: gpiomon
USE_GPIODETECT(NEWTOY(gpiodetect, ">0", TOYFLAG_USR|TOYFLAG_BIN))
USE_GPIOFIND(NEWTOY(gpioinfo, "", TOYFLAG_USR|TOYFLAG_BIN))
USE_GPIOGET(NEWTOY(gpioget, "<2l", TOYFLAG_USR|TOYFLAG_BIN))
USE_GPIOINFO(NEWTOY(gpiofind, "<1>1", TOYFLAG_USR|TOYFLAG_BIN))
USE_GPIOSET(NEWTOY(gpioset, "<2l", TOYFLAG_USR|TOYFLAG_BIN))
config GPIODETECT
bool "gpiodetect"
default y
help
usage: gpiodetect
Show all gpio chips' names, labels, and number of lines.
config GPIOFIND
bool "gpiofind"
default y
help
usage: gpiofind NAME
Show the chip and line number for the given line name.
config GPIOINFO
bool "gpioinfo"
default y
help
usage: gpioinfo [CHIP...]
Show gpio chips' lines.
config GPIOGET
bool "gpioget"
default y
help
usage: gpioget [-l] CHIP LINE...
Gets the values of the given lines on CHIP. Use gpiofind to convert line
names to numbers.
-l Active low
config GPIOSET
bool "gpioset"
default y
help
usage: gpioset [-l] CHIP LINE=VALUE...
Set the lines on CHIP to the given values. Use gpiofind to convert line
names to numbers.
-l Active low
*/
#define FOR_gpiodetect
#define TT this.gpiod
#include "toys.h"
GLOBALS(
struct arg_list *chips;
int chip_count;
)
#include <linux/gpio.h>
static int open_chip(char *chip)
{
sprintf(toybuf, isdigit(*chip) ? "/dev/gpiochip%s" : "/dev/%s", chip);
return xopen(toybuf, O_RDWR);
}
static int collect_chips(struct dirtree *node)
{
struct arg_list *new;
int n;
if (!node->parent) return DIRTREE_RECURSE; // Skip the directory itself.
if (sscanf(node->name, "gpiochip%d", &n)!=1) return 0;
new = xmalloc(sizeof(struct arg_list));
new->arg = strdup(node->name);
new->next = TT.chips;
TT.chips = new;
TT.chip_count++;
return 0;
}
static int comparator(const void *a, const void *b)
{
struct arg_list *lhs = *(struct arg_list **)a;
struct arg_list *rhs = *(struct arg_list **)b;
return strcmp(lhs->arg, rhs->arg);
}
static void foreach_chip(void (*cb)(char *name))
{
struct arg_list **sorted, *chip;
int i = 0;
dirtree_flagread("/dev", DIRTREE_SHUTUP, collect_chips);
sorted = xmalloc(TT.chip_count*sizeof(void *));
for (chip = TT.chips; chip; chip=chip->next, i++) sorted[i] = chip;
qsort(sorted, TT.chip_count, sizeof(void *), comparator);
for (i=0; i<TT.chip_count; i++) {
sprintf(toybuf, "/dev/%s", sorted[i]->arg);
cb(toybuf);
}
free(sorted);
llist_free_arg(TT.chips);
}
static void gpiodetect(char *path)
{
struct gpiochip_info chip;
int fd = xopen(path, O_RDWR);
xioctl(fd, GPIO_GET_CHIPINFO_IOCTL, &chip);
close(fd);
// gpiochip0 [pinctrl-bcm2711] (58 line)
printf("%s [%s] (%u line%s)\n", chip.name, chip.label, chip.lines,
chip.lines==1?"":"s");
}
void gpiodetect_main(void)
{
foreach_chip(gpiodetect);
}
#define FOR_gpiofind
#include "generated/flags.h"
static void gpiofind(char *path)
{
struct gpiochip_info chip;
struct gpioline_info line;
int fd = xopen(path, O_RDWR);
xioctl(fd, GPIO_GET_CHIPINFO_IOCTL, &chip);
for (line.line_offset=0; line.line_offset<chip.lines; line.line_offset++) {
xioctl(fd, GPIO_GET_LINEINFO_IOCTL, &line);
if (!strcmp(line.name, *toys.optargs)) {
printf("%s %d\n", chip.name, line.line_offset);
break;
}
}
close(fd);
}
void gpiofind_main(void)
{
foreach_chip(gpiofind);
}
#define FOR_gpioinfo
#include "generated/flags.h"
static void gpioinfo_fd(int fd)
{
struct gpiochip_info chip;
struct gpioline_info line;
xioctl(fd, GPIO_GET_CHIPINFO_IOCTL, &chip);
// gpiochip1 - 8 lines:
printf("%s - %d line%s:\n", chip.name, chip.lines, chip.lines==1?"":"s");
// line 4: "VDD_SD_IO_SEL" "vdd-sd-io" output active-high [used]
// We use slightly wider columns for the name and consumer; just wide enough
// to show all Raspberry Pi 400 pins without wrapping an 80-column terminal.
for (line.line_offset=0; line.line_offset<chip.lines; line.line_offset++) {
xioctl(fd, GPIO_GET_LINEINFO_IOCTL, &line);
if (*line.name) sprintf(toybuf, "\"%s\"", line.name);
else strcpy(toybuf, "unnamed");
if (*line.consumer) sprintf(toybuf+64, "\"%s\"", line.consumer);
else strcpy(toybuf+64, "unused");
printf("\tline %3d:%18s %18s", line.line_offset, toybuf, toybuf+64);
printf(" %sput", line.flags&GPIOLINE_FLAG_IS_OUT?"out":" in");
printf(" active-%s", line.flags&GPIOLINE_FLAG_ACTIVE_LOW?"low ":"high");
if (line.flags&GPIOLINE_FLAG_KERNEL) printf(" [used]");
printf("\n");
}
close(fd);
}
static void gpioinfo(char *path)
{
gpioinfo_fd(xopen(path, O_RDWR));
}
void gpioinfo_main(void)
{
int i;
if (!toys.optc) foreach_chip(gpioinfo);
else for (i = 0; toys.optargs[i]; i++) {
gpioinfo_fd(open_chip(toys.optargs[i]));
}
}
#define FOR_gpioget
#include "generated/flags.h"
void gpioget_main(void)
{
struct gpiohandle_request req = { .flags = GPIOHANDLE_REQUEST_INPUT };
struct gpiohandle_data data;
struct gpiochip_info chip;
char **args = toys.optargs;
int fd, line;
fd = open_chip(*args);
xioctl(fd, GPIO_GET_CHIPINFO_IOCTL, &chip);
if (FLAG(l)) req.flags |= GPIOHANDLE_REQUEST_ACTIVE_LOW;
for (args++; *args; args++, req.lines++) {
if (req.lines >= GPIOHANDLES_MAX) error_exit("too many requests!");
line = atolx_range(*args, 0, chip.lines);
req.lineoffsets[req.lines] = line;
}
xioctl(fd, GPIO_GET_LINEHANDLE_IOCTL, &req);
xioctl(req.fd, GPIOHANDLE_GET_LINE_VALUES_IOCTL, &data);
for (line=0; line<req.lines; line++) {
printf("%s%d", line>0 ? " " : "", data.values[line]);
}
xputc('\n');
}
#define FOR_gpioset
#include "generated/flags.h"
void gpioset_main(void)
{
struct gpiohandle_request req = { .flags = GPIOHANDLE_REQUEST_OUTPUT };
char **args = toys.optargs;
int fd, line, value;
fd = open_chip(*args);
if (FLAG(l)) req.flags |= GPIOHANDLE_REQUEST_ACTIVE_LOW;
for (args++; *args; args++, req.lines++) {
if (req.lines >= GPIOHANDLES_MAX) error_exit("too many requests!");
if (sscanf(*args, "%d=%d", &line, &value) != 2)
perror_exit("not LINE=VALUE: %s", *args);
req.lineoffsets[req.lines] = line;
req.default_values[req.lines] = value;
}
xioctl(fd, GPIO_GET_LINEHANDLE_IOCTL, &req);
}
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