src/superio/smsc/lpc47m15x/early_serial.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 /* Pre-RAM driver for the SMSC LPC47M15X Super I/O chip */
   4
   5 #include <arch/io.h>
   6 #include <device/pnp_ops.h>
   7 #include <device/pnp.h>
   8 #include <stdint.h>
   9
  10 #include "lpc47m15x.h"
  11
  12 static void pnp_enter_conf_state(pnp_devfn_t dev)
  13 {
  14         u16 port = dev >> 8;
  15         outb(0x55, port);
  16 }
  17
  18 static void pnp_exit_conf_state(pnp_devfn_t dev)
  19 {
  20         u16 port = dev >> 8;
  21         outb(0xaa, port);
  22 }
  23
  24 void lpc47m15x_enable_serial(pnp_devfn_t dev, u16 iobase)
  25 {
  26         pnp_enter_conf_state(dev);
  27         pnp_set_logical_device(dev);
  28         pnp_set_enable(dev, 0);
  29         pnp_set_iobase(dev, PNP_IDX_IO0, iobase);
  30         pnp_set_enable(dev, 1);
  31         pnp_exit_conf_state(dev);
  32 }