blob: f9719d167c8d74f3159d995b09899bc52eab8294 [file] [log] [blame]
/*
* Driver for 8250/16550-type serial ports
*
* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
*
* Copyright (C) 2001 Russell King.
*
* 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.
*/
#include <linux/serial_8250.h>
struct uart_8250_port {
struct uart_port port;
struct timer_list timer; /* "no irq" timer */
struct list_head list; /* ports on this IRQ */
unsigned short capabilities; /* port capabilities */
unsigned short bugs; /* port bugs */
unsigned int tx_loadsz; /* transmit fifo load size */
unsigned char acr;
unsigned char ier;
unsigned char lcr;
unsigned char mcr;
unsigned char mcr_mask; /* mask of user bits */
unsigned char mcr_force; /* mask of forced bits */
unsigned char cur_iotype; /* Running I/O type */
/*
* Some bits in registers are cleared on a read, so they must
* be saved whenever the register is read but the bits will not
* be immediately processed.
*/
#define LSR_SAVE_FLAGS UART_LSR_BRK_ERROR_BITS
unsigned char lsr_saved_flags;
#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
unsigned char msr_saved_flags;
/* 8250 specific callbacks */
int (*dl_read)(struct uart_8250_port *);
void (*dl_write)(struct uart_8250_port *, int);
};
struct old_serial_port {
unsigned int uart;
unsigned int baud_base;
unsigned int port;
unsigned int irq;
unsigned int flags;
unsigned char hub6;
unsigned char io_type;
unsigned char *iomem_base;
unsigned short iomem_reg_shift;
unsigned long irqflags;
};
/*
* This replaces serial_uart_config in include/linux/serial.h
*/
struct serial8250_config {
const char *name;
unsigned short fifo_size;
unsigned short tx_loadsz;
unsigned char fcr;
unsigned int flags;
};
#define UART_CAP_FIFO (1 << 8) /* UART has FIFO */
#define UART_CAP_EFR (1 << 9) /* UART has EFR */
#define UART_CAP_SLEEP (1 << 10) /* UART has IER sleep */
#define UART_CAP_AFE (1 << 11) /* MCR-based hw flow control */
#define UART_CAP_UUE (1 << 12) /* UART needs IER bit 6 set (Xscale) */
#define UART_CAP_RTOIE (1 << 13) /* UART needs IER bit 4 set (Xscale, Tegra) */
#define UART_BUG_QUOT (1 << 0) /* UART has buggy quot LSB */
#define UART_BUG_TXEN (1 << 1) /* UART has buggy TX IIR status */
#define UART_BUG_NOMSR (1 << 2) /* UART has buggy MSR status bits (Au1x00) */
#define UART_BUG_THRE (1 << 3) /* UART has buggy THRE reassertion */
#define PROBE_RSA (1 << 0)
#define PROBE_ANY (~0)
#define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
#ifdef CONFIG_SERIAL_8250_SHARE_IRQ
#define SERIAL8250_SHARE_IRQS 1
#else
#define SERIAL8250_SHARE_IRQS 0
#endif
static inline int serial_in(struct uart_8250_port *up, int offset)
{
return up->port.serial_in(&up->port, offset);
}
static inline void serial_out(struct uart_8250_port *up, int offset, int value)
{
up->port.serial_out(&up->port, offset, value);
}
void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
static inline int serial_dl_read(struct uart_8250_port *up)
{
return up->dl_read(up);
}
static inline void serial_dl_write(struct uart_8250_port *up, int value)
{
up->dl_write(up, value);
}
#if defined(__alpha__) && !defined(CONFIG_PCI)
/*
* Digital did something really horribly wrong with the OUT1 and OUT2
* lines on at least some ALPHA's. The failure mode is that if either
* is cleared, the machine locks up with endless interrupts.
*/
#define ALPHA_KLUDGE_MCR (UART_MCR_OUT2 | UART_MCR_OUT1)
#elif defined(CONFIG_SBC8560)
/*
* WindRiver did something similarly broken on their SBC8560 board. The
* UART tristates its IRQ output while OUT2 is clear, but they pulled
* the interrupt line _up_ instead of down, so if we register the IRQ
* while the UART is in that state, we die in an IRQ storm. */
#define ALPHA_KLUDGE_MCR (UART_MCR_OUT2)
#else
#define ALPHA_KLUDGE_MCR 0
#endif