pin_control: fib lib gitignore

This commit is contained in:
Alejandro Soto 2023-09-13 10:41:43 -06:00
parent 3da3cd544b
commit e841e69b47
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GPG key ID: 570448E3382BDEC5
3 changed files with 382 additions and 1 deletions

1
.gitignore vendored
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@ -87,7 +87,6 @@ dist/
downloads/
eggs/
.eggs/
lib/
lib64/
parts/
sdist/

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@ -0,0 +1,156 @@
#include <stdio.h>
#include <gpiod.h>
#include <pin_control.h>
// https://docs.kernel.org/driver-api/gpio/using-gpio.html
#define GPIO_CHIP "gpiochip0"
struct gpiod_chip *chip;
int init_gpio() {
cleanup_gpio();
// https://libgpiod-dlang.dpldocs.info/gpiod.gpiod_chip_open_by_name.html
chip = gpiod_chip_open_by_name(GPIO_CHIP);
if (!chip) {
perror("[pin_control] gpiod_chip_open_by_name(\"" GPIO_CHIP "\")");
return -1;
}
return 0;
}
void cleanup_gpio() {
// https://libgpiod-dlang.dpldocs.info/gpiod.gpiod_chip_close.html
if (chip) {
gpiod_chip_close(chip);
chip = NULL;
}
}
static int set_pin_state(int pin, int state) {
int ret = -1;
if (!chip) {
perror("[pin_control] attempt to set GPIO line for invalid chip");
goto exit;
}
// https://libgpiod-dlang.dpldocs.info/gpiod.gpiod_chip_get_line.html
struct gpiod_line *line = gpiod_chip_get_line(chip, pin); // this may need an offset
if (!line) {
perror("[pin_control] gpiod_chip_get_line()");
goto exit;
}
// https://libgpiod-dlang.dpldocs.info/gpiod.gpiod_line_request_output.html
if (gpiod_line_request_output(line, "house-leds", state) < 0) {
perror("[pin_control] gpiod_line_request_output()");
goto exit_line;
}
// https://libgpiod-dlang.dpldocs.info/gpiod.gpiod_line_set_value.html
if (gpiod_line_set_value(line, state) < 0) {
perror("[pin_control] gpiod_line_set_value()");
goto exit_line;
}
ret = 0;
exit_line:
// https://libgpiod-dlang.dpldocs.info/gpiod.gpiod_line_release.html
gpiod_line_release(line);
exit:
return ret;
}
int turn_on_pin(int pin) {
return set_pin_state(pin, 1);
}
int turn_off_pin(int pin) {
return set_pin_state(pin, 0);
}
int probe_pin(int pin) {
int ret = -1;
if (!chip) {
perror("[pin_control] attempt to read GPIO line for invalid chip");
goto exit;
}
struct gpiod_line *line = gpiod_chip_get_line(chip, pin);
if (!line) {
perror("[pin_control] gpiod_chip_get_line()");
goto exit;
} else if (gpiod_line_request_input(line, "house-leds") < 0) {
perror("[pin_control] gpiod_line_request_input()");
goto exit_line;
}
ret = gpiod_line_get_value(line);
if (ret < 0) {
perror("[pin_control] gpiod_line_get_value()");
goto exit_line;
}
exit_line:
// https://libgpiod-dlang.dpldocs.info/gpiod.gpiod_line_release.html
gpiod_line_release(line);
exit:
return ret;
}
int turn_on_all_pins() {
for (int pin = 0; pin <= 5; pin++)
if (turn_on_pin(pin) < 0)
return -1;
return 0;
}
int turn_off_all_pins() {
for (int pin = 0; pin <= 5; pin++) {
if (turn_off_pin(pin) < 0)
return -1;
}
return 0;
}
static int button_presssed(int event, unsigned int pin, const struct timespec * timestamp, void *data) {
(void) event;
(void) timestamp;
* (int *) data = (int) pin;
return GPIOD_CTXLESS_EVENT_POLL_RET_STOP;
}
int wait_for_button_press(const unsigned pins[static 5]) {
// https://www.lane-fu.com/linuxmirror/libgpiod/doc/html/group______high__level____.html#ga3ac28eb59bbd31b8b2298f76047d377d
int pressed_pin = -1;
struct timespec ts = {
.tv_sec = 3600,
.tv_nsec = 0,
};
int ret = gpiod_ctxless_event_monitor_multiple(
GPIO_CHIP,
GPIOD_CTXLESS_EVENT_FALLING_EDGE,
pins,
5,
true,
"house-leds",
&ts, // big timout
NULL,
button_presssed,
&pressed_pin);
if (ret < 0) {
perror("[pin_control] gpiod_ctxless_event_monitor_multiple()");
return -1;
}
return pressed_pin;
}

226
pin_control/lib/v4l2.c Normal file
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@ -0,0 +1,226 @@
// Derivado de https://gist.github.com/jayrambhia/5866483
#include <errno.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <unistd.h>
#include <linux/videodev2.h>
#include <pin_control.h>
static int xioctl(int fd, int request, void *arg)
{
int r;
do r = ioctl (fd, request, arg);
while (-1 == r && EINTR == errno);
return r;
}
static int print_caps(int fd)
{
struct v4l2_capability caps = {};
if (-1 == xioctl(fd, VIDIOC_QUERYCAP, &caps))
{
perror("Querying Capabilities");
return 1;
}
printf( "Driver Caps:\n"
" Driver: \"%s\"\n"
" Card: \"%s\"\n"
" Bus: \"%s\"\n"
" Version: %d.%d\n"
" Capabilities: %08x\n",
caps.driver,
caps.card,
caps.bus_info,
(caps.version>>16)&&0xff,
(caps.version>>24)&&0xff,
caps.capabilities);
struct v4l2_cropcap cropcap = {0};
cropcap.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (-1 == xioctl (fd, VIDIOC_CROPCAP, &cropcap))
{
perror("Querying Cropping Capabilities");
return 1;
}
printf( "Camera Cropping:\n"
" Bounds: %dx%d+%d+%d\n"
" Default: %dx%d+%d+%d\n"
" Aspect: %d/%d\n",
cropcap.bounds.width, cropcap.bounds.height, cropcap.bounds.left, cropcap.bounds.top,
cropcap.defrect.width, cropcap.defrect.height, cropcap.defrect.left, cropcap.defrect.top,
cropcap.pixelaspect.numerator, cropcap.pixelaspect.denominator);
struct v4l2_fmtdesc fmtdesc = {0};
fmtdesc.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
char fourcc[5] = {0};
char c, e;
printf(" FMT : CE Desc\n--------------------\n");
while (0 == xioctl(fd, VIDIOC_ENUM_FMT, &fmtdesc))
{
strncpy(fourcc, (char *)&fmtdesc.pixelformat, 4);
c = fmtdesc.flags & 1? 'C' : ' ';
e = fmtdesc.flags & 2? 'E' : ' ';
printf(" %s: %c%c %s\n", fourcc, c, e, fmtdesc.description);
fmtdesc.index++;
}
struct v4l2_format fmt = {0};
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
fmt.fmt.pix.width = 640;
fmt.fmt.pix.height = 480;
//fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_BGR24;
//fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_GREY;
fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_MJPEG;
fmt.fmt.pix.field = V4L2_FIELD_NONE;
if (-1 == xioctl(fd, VIDIOC_S_FMT, &fmt))
{
perror("Setting Pixel Format");
return 1;
}
strncpy(fourcc, (char *)&fmt.fmt.pix.pixelformat, 4);
printf( "Selected Camera Mode:\n"
" Width: %d\n"
" Height: %d\n"
" PixFmt: %s\n"
" Field: %d\n",
fmt.fmt.pix.width,
fmt.fmt.pix.height,
fourcc,
fmt.fmt.pix.field);
return 0;
}
static int init_mmap(int fd, uint8_t **buffer, size_t *buffer_len)
{
struct v4l2_requestbuffers req = {0};
req.count = 1;
req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
req.memory = V4L2_MEMORY_MMAP;
if (-1 == xioctl(fd, VIDIOC_REQBUFS, &req))
{
perror("Requesting Buffer");
return 1;
}
struct v4l2_buffer buf = {0};
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = 0;
if(-1 == xioctl(fd, VIDIOC_QUERYBUF, &buf))
{
perror("Querying Buffer");
return 1;
}
*buffer = mmap (NULL, buf.length, PROT_READ | PROT_WRITE, MAP_SHARED, fd, buf.m.offset);
*buffer_len = buf.length;
printf("Length: %d\nAddress: %p\n", buf.length, *buffer);
printf("Image Length: %d\n", buf.bytesused);
return 0;
}
static int capture_frame(int fd)
{
struct v4l2_buffer buf = {0};
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = 0;
if(-1 == xioctl(fd, VIDIOC_QBUF, &buf))
{
perror("Query Buffer");
return 1;
}
if(-1 == xioctl(fd, VIDIOC_STREAMON, &buf.type))
{
perror("Start Capture");
return 1;
}
fd_set fds;
FD_ZERO(&fds);
FD_SET(fd, &fds);
struct timeval tv = {0};
tv.tv_sec = 2;
int r = select(fd+1, &fds, NULL, NULL, &tv);
if(-1 == r)
{
perror("Waiting for Frame");
return 1;
}
if(-1 == xioctl(fd, VIDIOC_DQBUF, &buf))
{
perror("Retrieving Frame");
return 1;
}
return 0;
}
int save_image(const char *out, uint8_t *buffer, size_t buffer_len)
{
printf ("saving image\n");
int fd = open(out, O_WRONLY | O_CREAT | O_TRUNC, 0600);
if (fd < 0) {
fprintf(stderr, "open(\"%s\"): %m\n", out);
return -1;
}
int ret = 0;
while (buffer_len) {
ssize_t written = write(fd, buffer, buffer_len);
if (written < 0) {
perror("write()");
ret = -1;
break;
}
buffer += written;
buffer_len -= written;
}
close(fd);
return ret;
}
int capture_image(const char *out)
{
int fd = open("/dev/video0", O_RDWR);
if (fd < 0) {
perror("Opening video device");
return -1;
}
uint8_t *buffer = NULL;
size_t buffer_len;
int ret = print_caps(fd)
|| init_mmap(fd, &buffer, &buffer_len)
|| capture_frame(fd)
|| save_image(out, buffer, buffer_len);
close(fd);
if (buffer)
munmap(buffer, buffer_len);
return ret ? -1 : 0;
}