src/superio/winbond/w83627dhg/early_serial.c

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2
   3 #include <arch/io.h>
   4 #include <device/pnp_ops.h>
   5 #include <stdint.h>
   6 #include "w83627dhg.h"
   7
   8 void pnp_enter_ext_func_mode(pnp_devfn_t dev)
   9 {
  10         u16 port = dev >> 8;
  11         outb(0x87, port);
  12         outb(0x87, port);
  13 }
  14
  15 void pnp_exit_ext_func_mode(pnp_devfn_t dev)
  16 {
  17         u16 port = dev >> 8;
  18         outb(0xaa, port);
  19 }
  20
  21 /**
  22  * Select Pin 89, Pin 90 function as I2C interface SDA, SCL.
  23  *  {Pin 89, Pin 90} function can be selected as {GP33, GP32}, or
  24  *  {RSTOUT3#, RSTOUT2#} or {SDA, SCL}
  25  */
  26 void w83627dhg_enable_i2c(pnp_devfn_t dev)
  27 {
  28         u8 val;
  29
  30         pnp_enter_ext_func_mode(dev);
  31         pnp_set_logical_device(dev);
  32
  33         val = pnp_read_config(dev, 0x2A);
  34         val |= 1 << 1;
  35         pnp_write_config(dev, 0x2A, val);
  36
  37         pnp_exit_ext_func_mode(dev);
  38 }
  39
  40 void w83627dhg_set_clksel_48(pnp_devfn_t dev)
  41 {
  42         u8 reg8;
  43
  44         pnp_enter_ext_func_mode(dev);
  45         reg8 = pnp_read_config(dev, 0x24);
  46         reg8 |= (1 << 6); /* Set CLKSEL (clock input on pin 1) to 48MHz. */
  47         pnp_write_config(dev, 0x24, reg8);
  48         pnp_exit_ext_func_mode(dev);
  49 }