drivers/misc/nuvoton_nct6102d.c

   1 /*
   2  * Copyright (C) 2016 Stefan Roese <sr@denx.de>
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <nuvoton_nct6102d.h>
   9 #include <asm/io.h>
  10 #include <asm/pnp_def.h>
  11
  12 static void superio_outb(int reg, int val)
  13 {
  14         outb(reg, NCT_EFER);
  15         outb(val, NCT_EFDR);
  16 }
  17
  18 static inline int superio_inb(int reg)
  19 {
  20         outb(reg, NCT_EFER);
  21         return inb(NCT_EFDR);
  22 }
  23
  24 static int superio_enter(void)
  25 {
  26         outb(NCT_ENTRY_KEY, NCT_EFER); /* Enter extended function mode */
  27         outb(NCT_ENTRY_KEY, NCT_EFER); /* Again according to manual */
  28
  29         return 0;
  30 }
  31
  32 static void superio_select(int ld)
  33 {
  34         superio_outb(NCT_LD_SELECT_REG, ld);
  35 }
  36
  37 static void superio_exit(void)
  38 {
  39         outb(NCT_EXIT_KEY, NCT_EFER); /* Leave extended function mode */
  40 }
  41
  42 /*
  43  * The Nuvoton NCT6102D starts per default after reset with both,
  44  * the internal watchdog and the internal legacy UART enabled. This
  45  * code provides a function to disable the watchdog.
  46  */
  47 int nct6102d_wdt_disable(void)
  48 {
  49         superio_enter();
  50         /* Select logical device for WDT */
  51         superio_select(NCT6102D_LD_WDT);
  52         superio_outb(NCT6102D_WDT_TIMEOUT, 0x00);
  53         superio_exit();
  54
  55         return 0;
  56 }