Hello,
I posted this message to linix-gpio group about a week ago, but it didn't get
any reply so far; thus trying here.
I am developing a driver for PCIe-based device that needs to receive external
signals through on-board GPIOs. The target platform is Intel-based board
running Fedora 34 kernel 5.11.12-300.fc34.x86_64 and has GPIO controller driven
by gpio-it87.
# gpiodetect
gpiochip0 [INT34BB:00] (312 lines)
gpiochip1 [gpio_it87] (64 lines)
8 of available 64 lines are connected to a header on the board:
# gpioinfo 1
...
line 49: "it87_gp71" unused input active-high
line 50: "it87_gp72" unused input active-high
line 51: "it87_gp73" unused input active-high
line 52: "it87_gp74" unused input active-high
line 53: "it87_gp75" unused input active-high
line 54: "it87_gp76" unused input active-high
line 55: "it87_gp77" unused input active-high
...
These lines were verified with logic analyzer and `gpioset 1 nn=0|1`
The PCIe device driver defines these lines as:
static struct gpiod_lookup_table gpio_it87_gpios = {
.dev_id = "gpio_it87",
.table = {
GPIO_LOOKUP("gpio-it87", 48, "it87_gp70", GPIO_ACTIVE_HIGH),
GPIO_LOOKUP("gpio-it87", 49, "it87_gp71", GPIO_ACTIVE_HIGH),
GPIO_LOOKUP("gpio-it87", 50, "it87_gp72", GPIO_ACTIVE_HIGH),
GPIO_LOOKUP("gpio-it87", 51, "it87_gp73", GPIO_ACTIVE_HIGH),
GPIO_LOOKUP("gpio-it87", 52, "it87_gp74", GPIO_ACTIVE_HIGH),
GPIO_LOOKUP("gpio-it87", 53, "it87_gp75", GPIO_ACTIVE_HIGH),
GPIO_LOOKUP("gpio-it87", 54, "it87_gp76", GPIO_ACTIVE_HIGH),
GPIO_LOOKUP("gpio-it87", 55, "it87_gp77", GPIO_ACTIVE_HIGH),
{},
},
};
and then adds them to lookup table, eg.:
gpiod_add_lookup_table(&gpio_it87_gpios);
However, none of those lines seem available
struct desc *gpio = gpiod_get(dev, "it87_gp70", GPIOD_IN);
Above returns -ENOENT for any of those lines. I believe it is due to incorrct
lookup definions in gpio_it87_gpios above, however, I cannot figure out what
is wrong there. What am I missing?
Thanks,
--Alex
_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@xxxxxxxxxxxxxxxxx
https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
