LXR linux/arch/arm/mach-davinci/serial.c

   1/*
   2 * TI DaVinci serial driver
   3 *
   4 * Copyright (C) 2006 Texas Instruments.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 *  You should have received a copy of the GNU General Public License
  17 *  along with this program; if not, write to the Free Software
  18 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 *
  20 */
  21
  22#include <linux/kernel.h>
  23#include <linux/init.h>
  24#include <linux/serial_8250.h>
  25#include <linux/serial_reg.h>
  26#include <linux/platform_device.h>
  27#include <linux/delay.h>
  28#include <linux/clk.h>
  29
  30#include <asm/io.h>
  31#include <asm/irq.h>
  32#include <mach/hardware.h>
  33#include <mach/serial.h>
  34#include <mach/irqs.h>
  35
  36#define UART_DAVINCI_PWREMU 0x0c
  37
  38static inline unsigned int davinci_serial_in(struct plat_serial8250_port *up,
  39                                          int offset)
  40{
  41        offset <<= up->regshift;
  42        return (unsigned int)__raw_readb(up->membase + offset);
  43}
  44
  45static inline void davinci_serial_outp(struct plat_serial8250_port *p,
  46                                       int offset, int value)
  47{
  48        offset <<= p->regshift;
  49        __raw_writeb(value, p->membase + offset);
  50}
  51
  52static struct plat_serial8250_port serial_platform_data[] = {
  53        {
  54                .membase        = (char *)IO_ADDRESS(DAVINCI_UART0_BASE),
  55                .mapbase        = (unsigned long)DAVINCI_UART0_BASE,
  56                .irq            = IRQ_UARTINT0,
  57                .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
  58                .iotype         = UPIO_MEM,
  59                .regshift       = 2,
  60                .uartclk        = 27000000,
  61        },
  62        {
  63                .flags          = 0
  64        },
  65};
  66
  67static struct platform_device serial_device = {
  68        .name                   = "serial8250",
  69        .id                     = PLAT8250_DEV_PLATFORM,
  70        .dev                    = {
  71                .platform_data  = serial_platform_data,
  72        },
  73};
  74
  75static void __init davinci_serial_reset(struct plat_serial8250_port *p)
  76{
  77        /* reset both transmitter and receiver: bits 14,13 = UTRST, URRST */
  78        unsigned int pwremu = 0;
  79
  80        davinci_serial_outp(p, UART_IER, 0);  /* disable all interrupts */
  81
  82        davinci_serial_outp(p, UART_DAVINCI_PWREMU, pwremu);
  83        mdelay(10);
  84
  85        pwremu |= (0x3 << 13);
  86        pwremu |= 0x1;
  87        davinci_serial_outp(p, UART_DAVINCI_PWREMU, pwremu);
  88}
  89
  90static int __init davinci_init(void)
  91{
  92        davinci_serial_reset(&serial_platform_data[0]);
  93        return platform_device_register(&serial_device);
  94}
  95
  96arch_initcall(davinci_init);
  97