I have a functioning U-Boot on my IMX6SX-based board. I am using the imx6sxsabresd u-boot and Linux configurations. I am able to toggle GPIO during U-Boot boot up. I am attempting to toggle the exact same GPIO during Linux boot up so I can use the GPIO toggling as a debug marker (I do not have serial on Linux yet).
I am using source from imx-yocto-L4.9.88_2.0.0.
Below is my code in U-Ｂｏｏt that successfully toggles the GPIO (pin 6, pad 1).
static iomux_v3_cfg_t const test_gpio_pads[] = {
MX6_PAD_GPIO1_IO06__GPIO1_IO_6 | MUX_PAD_CTRL(NO_PAD_CTRL),
MX6_PAD_GPIO1_IO07__GPIO1_IO_7 | MUX_PAD_CTRL(NO_PAD_CTRL),
};
static void test_gpio(void)
{
int i;
imx_iomux_v3_setup_multiple_pads(test_gpio_pads, ARRAY_SIZE(test_gpio_pads));
gpio_request(IMX_GPIO_NR(1, 6), "GPIO Pad 1 Pin 6");
for(i=0; i<3; i++) {
printf("%d: GPIO on\r\n", i);
gpio_direction_output(IMX_GPIO_NR(1, 6), 1);
gpio_set_value(IMX_GPIO_NR(1, 6), 1);
mdelay(1000);
printf("%d: GPIO off\r\n", i);
gpio_direction_output(IMX_GPIO_NR(1, 6), 0);
gpio_set_value(IMX_GPIO_NR(1, 6), 0);
mdelay(1000);
}
printf("Ending GPIO test\r\n");
}
How would I do the equivalent in Linux?
Thanks in advance.
