drivers/misc/ibmasm/uart.c

/*
 * IBM ASM Service Processor Device Driver
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Copyright (C) IBM Corporation, 2004
 *
 * Author: Max Asböck <amax@us.ibm.com> 
 *
 */

#include <linux/termios.h>
#include <linux/tty.h>
#include <linux/serial_core.h>
#include <linux/serial_reg.h>
#include <linux/serial_8250.h>
#include "ibmasm.h"
#include "lowlevel.h"


void ibmasm_register_uart(struct service_processor *sp)
{
	struct uart_port uport;
	void __iomem *iomem_base;

	iomem_base = sp->base_address + SCOUT_COM_B_BASE;

	/* read the uart scratch register to determine if the UART
	 * is dedicated to the service processor or if the OS can use it
	 */
	if (0 == readl(iomem_base + UART_SCR)) {
		dev_info(sp->dev, "IBM SP UART not registered, owned by service processor\n");
		sp->serial_line = -1;
		return;
	}

	memset(&uport, 0, sizeof(struct uart_port));
	uport.irq	= sp->irq;
	uport.uartclk	= 3686400;
	uport.flags	= UPF_AUTOPROBE | UPF_SHARE_IRQ;
	uport.iotype	= UPIO_MEM;
	uport.membase	= iomem_base;

	sp->serial_line = serial8250_register_port(&uport);
	if (sp->serial_line < 0) {
		dev_err(sp->dev, "Failed to register serial port\n");
		return;
	}
	enable_uart_interrupts(sp->base_address);
}

void ibmasm_unregister_uart(struct service_processor *sp)
{
	if (sp->serial_line < 0)
		return;

	disable_uart_interrupts(sp->base_address);
	serial8250_unregister_port(sp->serial_line);
}