Hi all ~
I'm trying to control GPIO input in own application.
and I refered to below wiki.
https://wiki.st.com/stm32mpu/wiki/How_to_control_a_GPIO_in_userspace
this is my code.
gint gpiochip_fd, ret;
gchar gpiochip_path[20];
struct gpioevent_request in_req;
struct gpiohandle_request out_req;
// IN1 PB12 gpiochip1
// IN2 PB5 gpiochip1
// IN3 PH6 gpiochip7
// IN4 PD15 gpiochip3
// IN5 PD14 gpiochip3
// IN6 PD11 gpiochip3
// IN7 PE7 gpiochip4
// IN8 PE9 gpiochip4
// IN9 PE8 gpiochip4
// IN10 PG9 gpiochip6
// IN11 PE10 gpiochip4
// IN12 PD12 gpiochip3
gint idx;
gint in_gpio_chipno[NO_INPUT] = {1, 1, 7, 3, 3, 3, 4, 4, 4, 6, 4, 3};
gint in_gpio_lineoffset[NO_INPUT] = {12, 5, 6, 15, 14, 11, 7, 9, 8, 9, 10, 12};
for (idx=0; idx<NO_INPUT; idx++) {
g_sprintf(gpiochip_path, "/dev/gpiochip%d", in_gpio_chipno[idx]);
gpiochip_fd = open (gpiochip_path, O_RDWR);
if (gpiochip_fd == -1)
fprintf(stderr, "Failed to open %s\n", gpiochip_path);
else {
in_req.lineoffset = in_gpio_lineoffset[idx];
in_req.eventflags = GPIOEVENT_REQUEST_BOTH_EDGES;
in_req.handleflags = GPIOHANDLE_REQUEST_INPUT;
ret = ioctl(gpiochip_fd, GPIO_GET_LINEEVENT_IOCTL, &in_req);
if (ret == -1) {
in_fd[idx] = -1;
fprintf(stderr, "Failed to issue GPIO_GET_LINEEVENT_IOCTL (%d)\n", -errno);
} else {
in_fd[idx] = in_req.fd;
in_gio[idx] = g_io_channel_unix_new (in_req.fd);
in_gsrc[idx] = g_io_create_watch (in_gio[idx], G_IO_IN);
g_source_set_callback (in_gsrc[idx], (GSourceFunc)gpio_event_cb, GINT_TO_POINTER(idx), NULL);
g_source_attach (in_gsrc[idx], g_main_loop_get_context (Threads_GetMainLoop(MLID_Gpio)));
g_source_unref (in_gsrc[idx]);
}
if (close(gpiochip_fd) == -1)
perror("Failed to close GPIO character device file");
}
}
When I run application, 3 input pins (PE9, PG9, PD12) return error like below.
Failed to issue GPIO_GET_LINEEVENT_IOCTL (-19)
And the kernel log printed as below.
[ 5366.798479] stm32mp157-pinctrl soc:pinctrl@50002000: irq line 9 already requested.
[ 5366.812031] stm32mp157-pinctrl soc:pinctrl@50002000: irq line 9 already requested.
[ 5366.825262] stm32mp157-pinctrl soc:pinctrl@50002000: irq line 12 already requested.
below is my gpio info of these pins.
line 9: "PE9" unused input active-high
line 9: "PG9" unused input active-high
line 12: "PD12" unused input active-high
Where should I check to solve this problem?
Thanks in advanced.
