LXR linux/drivers/misc/ibmasm/uart.c

   1
   2/*
   3 * IBM ASM Service Processor Device Driver
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License as published by
   7 * the Free Software Foundation; either version 2 of the License, or
   8 * (at your option) any later version.
   9 *
  10 * This program is distributed in the hope that it will be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program; if not, write to the Free Software
  17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18 *
  19 * Copyright (C) IBM Corporation, 2004
  20 *
  21 * Author: Max Asböck <amax@us.ibm.com>
  22 *
  23 */
  24
  25#include <linux/termios.h>
  26#include <linux/tty.h>
  27#include <linux/serial_core.h>
  28#include <linux/serial_reg.h>
  29#include <linux/serial_8250.h>
  30#include "ibmasm.h"
  31#include "lowlevel.h"
  32
  33
  34void ibmasm_register_uart(struct service_processor *sp)
  35{
  36        struct uart_port uport;
  37        void __iomem *iomem_base;
  38
  39        iomem_base = sp->base_address + SCOUT_COM_B_BASE;
  40
  41        /* read the uart scratch register to determine if the UART
  42         * is dedicated to the service processor or if the OS can use it
  43         */
  44        if (0 == readl(iomem_base + UART_SCR)) {
  45                dev_info(sp->dev, "IBM SP UART not registered, owned by service processor\n");
  46                sp->serial_line = -1;
  47                return;
  48        }
  49
  50        memset(&uport, 0, sizeof(struct uart_port));
  51        uport.irq       = sp->irq;
  52        uport.uartclk   = 3686400;
  53        uport.flags     = UPF_SHARE_IRQ;
  54        uport.iotype    = UPIO_MEM;
  55        uport.membase   = iomem_base;
  56
  57        sp->serial_line = serial8250_register_port(&uport);
  58        if (sp->serial_line < 0) {
  59                dev_err(sp->dev, "Failed to register serial port\n");
  60                return;
  61        }
  62        enable_uart_interrupts(sp->base_address);
  63}
  64
  65void ibmasm_unregister_uart(struct service_processor *sp)
  66{
  67        if (sp->serial_line < 0)
  68                return;
  69
  70        disable_uart_interrupts(sp->base_address);
  71        serial8250_unregister_port(sp->serial_line);
  72}
  73