drivers/tty/serial/8250/8250.h

   1 /*
   2  *  Driver for 8250/16550-type serial ports
   3  *
   4  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
   5  *
   6  *  Copyright (C) 2001 Russell King.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #include <linux/serial_8250.h>
  15
  16 struct uart_8250_port {
  17         struct uart_port        port;
  18         struct timer_list       timer;          /* "no irq" timer */
  19         struct list_head        list;           /* ports on this IRQ */
  20         unsigned short          capabilities;   /* port capabilities */
  21         unsigned short          bugs;           /* port bugs */
  22         unsigned int            tx_loadsz;      /* transmit fifo load size */
  23         unsigned char           acr;
  24         unsigned char           ier;
  25         unsigned char           lcr;
  26         unsigned char           mcr;
  27         unsigned char           mcr_mask;       /* mask of user bits */
  28         unsigned char           mcr_force;      /* mask of forced bits */
  29         unsigned char           cur_iotype;     /* Running I/O type */
  30
  31         /*
  32          * Some bits in registers are cleared on a read, so they must
  33          * be saved whenever the register is read but the bits will not
  34          * be immediately processed.
  35          */
  36 #define LSR_SAVE_FLAGS UART_LSR_BRK_ERROR_BITS
  37         unsigned char           lsr_saved_flags;
  38 #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
  39         unsigned char           msr_saved_flags;
  40
  41         /* 8250 specific callbacks */
  42         int                     (*dl_read)(struct uart_8250_port *);
  43         void                    (*dl_write)(struct uart_8250_port *, int);
  44 };
  45
  46 struct old_serial_port {
  47         unsigned int uart;
  48         unsigned int baud_base;
  49         unsigned int port;
  50         unsigned int irq;
  51         unsigned int flags;
  52         unsigned char hub6;
  53         unsigned char io_type;
  54         unsigned char *iomem_base;
  55         unsigned short iomem_reg_shift;
  56         unsigned long irqflags;
  57 };
  58
  59 /*
  60  * This replaces serial_uart_config in include/linux/serial.h
  61  */
  62 struct serial8250_config {
  63         const char      *name;
  64         unsigned short  fifo_size;
  65         unsigned short  tx_loadsz;
  66         unsigned char   fcr;
  67         unsigned int    flags;
  68 };
  69
  70 #define UART_CAP_FIFO   (1 << 8)        /* UART has FIFO */
  71 #define UART_CAP_EFR    (1 << 9)        /* UART has EFR */
  72 #define UART_CAP_SLEEP  (1 << 10)       /* UART has IER sleep */
  73 #define UART_CAP_AFE    (1 << 11)       /* MCR-based hw flow control */
  74 #define UART_CAP_UUE    (1 << 12)       /* UART needs IER bit 6 set (Xscale) */
  75 #define UART_CAP_RTOIE  (1 << 13)       /* UART needs IER bit 4 set (Xscale, Tegra) */
  76
  77 #define UART_BUG_QUOT   (1 << 0)        /* UART has buggy quot LSB */
  78 #define UART_BUG_TXEN   (1 << 1)        /* UART has buggy TX IIR status */
  79 #define UART_BUG_NOMSR  (1 << 2)        /* UART has buggy MSR status bits (Au1x00) */
  80 #define UART_BUG_THRE   (1 << 3)        /* UART has buggy THRE reassertion */
  81
  82 #define PROBE_RSA       (1 << 0)
  83 #define PROBE_ANY       (~0)
  84
  85 #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
  86
  87 #ifdef CONFIG_SERIAL_8250_SHARE_IRQ
  88 #define SERIAL8250_SHARE_IRQS 1
  89 #else
  90 #define SERIAL8250_SHARE_IRQS 0
  91 #endif
  92
  93 static inline int serial_in(struct uart_8250_port *up, int offset)
  94 {
  95         return up->port.serial_in(&up->port, offset);
  96 }
  97
  98 static inline void serial_out(struct uart_8250_port *up, int offset, int value)
  99 {
 100         up->port.serial_out(&up->port, offset, value);
 101 }
 102
 103 void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
 104
 105 static inline int serial_dl_read(struct uart_8250_port *up)
 106 {
 107         return up->dl_read(up);
 108 }
 109
 110 static inline void serial_dl_write(struct uart_8250_port *up, int value)
 111 {
 112         up->dl_write(up, value);
 113 }
 114
 115 #if defined(__alpha__) && !defined(CONFIG_PCI)
 116 /*
 117  * Digital did something really horribly wrong with the OUT1 and OUT2
 118  * lines on at least some ALPHA's.  The failure mode is that if either
 119  * is cleared, the machine locks up with endless interrupts.
 120  */
 121 #define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
 122 #elif defined(CONFIG_SBC8560)
 123 /*
 124  * WindRiver did something similarly broken on their SBC8560 board. The
 125  * UART tristates its IRQ output while OUT2 is clear, but they pulled
 126  * the interrupt line _up_ instead of down, so if we register the IRQ
 127  * while the UART is in that state, we die in an IRQ storm. */
 128 #define ALPHA_KLUDGE_MCR (UART_MCR_OUT2)
 129 #else
 130 #define ALPHA_KLUDGE_MCR 0
 131 #endif