drivers/misc/nuvoton_nct6102d.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2016 Stefan Roese <sr@denx.de>
   4  */
   5
   6 #include <common.h>
   7 #include <nuvoton_nct6102d.h>
   8 #include <asm/io.h>
   9 #include <asm/pnp_def.h>
  10
  11 static void superio_outb(int reg, int val)
  12 {
  13         outb(reg, NCT_EFER);
  14         outb(val, NCT_EFDR);
  15 }
  16
  17 static inline int superio_inb(int reg)
  18 {
  19         outb(reg, NCT_EFER);
  20         return inb(NCT_EFDR);
  21 }
  22
  23 static int superio_enter(void)
  24 {
  25         outb(NCT_ENTRY_KEY, NCT_EFER); /* Enter extended function mode */
  26         outb(NCT_ENTRY_KEY, NCT_EFER); /* Again according to manual */
  27
  28         return 0;
  29 }
  30
  31 static void superio_select(int ld)
  32 {
  33         superio_outb(NCT_LD_SELECT_REG, ld);
  34 }
  35
  36 static void superio_exit(void)
  37 {
  38         outb(NCT_EXIT_KEY, NCT_EFER); /* Leave extended function mode */
  39 }
  40
  41 /*
  42  * The Nuvoton NCT6102D starts per default after reset with both,
  43  * the internal watchdog and the internal legacy UART enabled. This
  44  * code provides a function to disable the watchdog.
  45  */
  46 int nct6102d_wdt_disable(void)
  47 {
  48         superio_enter();
  49         /* Select logical device for WDT */
  50         superio_select(NCT6102D_LD_WDT);
  51         superio_outb(NCT6102D_WDT_TIMEOUT, 0x00);
  52         superio_exit();
  53
  54         return 0;
  55 }