Tool/software: Linux
Hi all
as title, our custom board have HW watch dog, the watch dog timer is connect to GPIO2_22, so I need to clean watchdog timer every sec.
I follow the step:
1. defined the GPIO pin mux: in am335x/mux.c
static struct module_pin_mux __maybe_unused gpio2_22_pin_mux[] = {
{OFFSET(lcd_vsync), (MODE(7) | PULLUDEN)}, /* advantech watch dog timer */
{-1},
};
...
...
void enable_board_pin_mux(void)
{
configure_module_pin_mux(gpio2_22_pin_mux);
#ifdef CONFIG_NAND
configure_module_pin_mux(nand_pin_mux);
#endif
configure_module_pin_mux(i2c1_pin_mux);
configure_module_pin_mux(gpio0_7_pin_mux);
configure_module_pin_mux(rmii1_pin_mux);
configure_module_pin_mux(rmii2_pin_mux);
configure_module_pin_mux(mmc0_pin_mux_sk_evm);
}
2. in arch/arm/cpu/armv7/am33xx/board.c will enable the pin:
int board_early_init_f(void)
{
prcm_init();
set_mux_conf_regs(); //enable watchdog
/* Add here to clean watch dog */
ADV_CLEAN_WDI();
#if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_RTC_ONLY_SUPPORT)
update_rtc_magic();
#endif
return 0;
}
3. I want to pull high/low after `set_mux_conf_regs()`, can I use __raw_write(value, reg). to control the gpio?
if so , what is the GPIO2_22 address?
