You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
96 lines
2.1 KiB
96 lines
2.1 KiB
#include "selfdrive/common/touch.h"
|
|
|
|
#include <assert.h>
|
|
#include <dirent.h>
|
|
#include <fcntl.h>
|
|
#include <linux/input.h>
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <sys/poll.h>
|
|
#include <unistd.h>
|
|
|
|
/* this macro is used to tell if "bit" is set in "array"
|
|
* it selects a byte from the array, and does a boolean AND
|
|
* operation with a byte that only has the relevant bit set.
|
|
* eg. to check for the 12th bit, we do (array[1] & 1<<4)
|
|
*/
|
|
#define test_bit(bit, array) (array[bit/8] & (1<<(bit%8)))
|
|
|
|
static int find_dev() {
|
|
int err;
|
|
|
|
int ret = -1;
|
|
|
|
DIR *dir = opendir("/dev/input");
|
|
assert(dir);
|
|
struct dirent* de = NULL;
|
|
while ((de = readdir(dir))) {
|
|
if (strncmp(de->d_name, "event", 5)) continue;
|
|
|
|
int fd = openat(dirfd(dir), de->d_name, O_RDONLY);
|
|
assert(fd >= 0);
|
|
|
|
unsigned char ev_bits[KEY_MAX / 8 + 1];
|
|
err = ioctl(fd, EVIOCGBIT(EV_ABS, sizeof(ev_bits)), ev_bits);
|
|
assert(err >= 0);
|
|
|
|
if (test_bit(ABS_MT_POSITION_X, ev_bits) && test_bit(ABS_MT_POSITION_Y, ev_bits)) {
|
|
ret = fd;
|
|
break;
|
|
}
|
|
close(fd);
|
|
}
|
|
closedir(dir);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void touch_init(TouchState *s) {
|
|
s->fd = find_dev();
|
|
assert(s->fd >= 0);
|
|
}
|
|
|
|
int touch_poll(TouchState *s, int* out_x, int* out_y, int timeout) {
|
|
assert(out_x && out_y);
|
|
bool up = false;
|
|
while (true) {
|
|
struct pollfd polls[] = {{
|
|
.fd = s->fd,
|
|
.events = POLLIN,
|
|
}};
|
|
int err = poll(polls, 1, timeout);
|
|
if (err < 0) {
|
|
return -1;
|
|
}
|
|
if (!(polls[0].revents & POLLIN)) {
|
|
break;
|
|
}
|
|
|
|
struct input_event event;
|
|
err = read(polls[0].fd, &event, sizeof(event));
|
|
if (err < sizeof(event)) {
|
|
return -1;
|
|
}
|
|
|
|
switch (event.type) {
|
|
case EV_ABS:
|
|
if (event.code == ABS_MT_POSITION_X) {
|
|
s->last_x = event.value;
|
|
} else if (event.code == ABS_MT_POSITION_Y) {
|
|
s->last_y = event.value;
|
|
} else if (event.code == ABS_MT_TRACKING_ID && event.value != -1) {
|
|
up = true;
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
if (up) {
|
|
// adjust for flippening
|
|
*out_x = s->last_y;
|
|
*out_y = 1080 - s->last_x;
|
|
}
|
|
return up;
|
|
}
|
|
|