![Russell King](/assets/img/avatar_default.png)
Glen Turner reported that writing LFCR rather than the more traditional CRLF causes issues with some terminals. Since this aflicts many serial drivers, extract the common code to a library function (uart_console_write) and arrange for each driver to supply a "putchar" function. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
1289 lines
31 KiB
C
1289 lines
31 KiB
C
/*
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* Driver for 8250/16550-type serial ports
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*
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* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
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*
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* Copyright (C) 2001 Russell King.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* A note about mapbase / membase
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*
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* mapbase is the physical address of the IO port. Currently, we don't
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* support this very well, and it may well be dropped from this driver
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* in future. As such, mapbase should be NULL.
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*
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* membase is an 'ioremapped' cookie. This is compatible with the old
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* serial.c driver, and is currently the preferred form.
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*/
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#include <linux/config.h>
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#include <linux/module.h>
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#include <linux/tty.h>
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#include <linux/ioport.h>
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#include <linux/init.h>
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#include <linux/console.h>
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#include <linux/sysrq.h>
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#include <linux/serial.h>
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#include <linux/serialP.h>
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#include <linux/delay.h>
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#include <asm/serial.h>
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#include <asm/io.h>
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#include <asm/irq.h>
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#include <asm/mach-au1x00/au1000.h>
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#if defined(CONFIG_SERIAL_AU1X00_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
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#define SUPPORT_SYSRQ
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#endif
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#include <linux/serial_core.h>
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#include "8250.h"
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/*
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* Debugging.
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*/
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#if 0
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#define DEBUG_AUTOCONF(fmt...) printk(fmt)
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#else
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#define DEBUG_AUTOCONF(fmt...) do { } while (0)
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#endif
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#if 0
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#define DEBUG_INTR(fmt...) printk(fmt)
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#else
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#define DEBUG_INTR(fmt...) do { } while (0)
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#endif
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#define PASS_LIMIT 256
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/*
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* We default to IRQ0 for the "no irq" hack. Some
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* machine types want others as well - they're free
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* to redefine this in their header file.
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*/
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#define is_real_interrupt(irq) ((irq) != 0)
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static struct old_serial_port old_serial_port[] = {
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{ .baud_base = 0,
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.iomem_base = (u8 *)UART0_ADDR,
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.irq = AU1000_UART0_INT,
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.flags = STD_COM_FLAGS,
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.iomem_reg_shift = 2,
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}, {
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.baud_base = 0,
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.iomem_base = (u8 *)UART1_ADDR,
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.irq = AU1000_UART1_INT,
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.flags = STD_COM_FLAGS,
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.iomem_reg_shift = 2
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}, {
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.baud_base = 0,
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.iomem_base = (u8 *)UART2_ADDR,
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.irq = AU1000_UART2_INT,
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.flags = STD_COM_FLAGS,
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.iomem_reg_shift = 2
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}, {
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.baud_base = 0,
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.iomem_base = (u8 *)UART3_ADDR,
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.irq = AU1000_UART3_INT,
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.flags = STD_COM_FLAGS,
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.iomem_reg_shift = 2
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}
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};
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#define UART_NR ARRAY_SIZE(old_serial_port)
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struct uart_8250_port {
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struct uart_port port;
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struct timer_list timer; /* "no irq" timer */
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struct list_head list; /* ports on this IRQ */
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unsigned short rev;
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unsigned char acr;
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unsigned char ier;
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unsigned char lcr;
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unsigned char mcr_mask; /* mask of user bits */
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unsigned char mcr_force; /* mask of forced bits */
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unsigned char lsr_break_flag;
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/*
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* We provide a per-port pm hook.
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*/
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void (*pm)(struct uart_port *port,
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unsigned int state, unsigned int old);
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};
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struct irq_info {
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spinlock_t lock;
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struct list_head *head;
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};
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static struct irq_info irq_lists[NR_IRQS];
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/*
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* Here we define the default xmit fifo size used for each type of UART.
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*/
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static const struct serial_uart_config uart_config[PORT_MAX_8250+1] = {
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{ "unknown", 1, 0 },
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{ "8250", 1, 0 },
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{ "16450", 1, 0 },
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{ "16550", 1, 0 },
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/* PORT_16550A */
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{ "AU1X00_UART",16, UART_CLEAR_FIFO | UART_USE_FIFO },
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};
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static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset)
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{
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return au_readl((unsigned long)up->port.membase + offset);
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}
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static _INLINE_ void
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serial_out(struct uart_8250_port *up, int offset, int value)
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{
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au_writel(value, (unsigned long)up->port.membase + offset);
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}
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#define serial_inp(up, offset) serial_in(up, offset)
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#define serial_outp(up, offset, value) serial_out(up, offset, value)
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/*
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* This routine is called by rs_init() to initialize a specific serial
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* port. It determines what type of UART chip this serial port is
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* using: 8250, 16450, 16550, 16550A. The important question is
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* whether or not this UART is a 16550A or not, since this will
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* determine whether or not we can use its FIFO features or not.
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*/
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static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
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{
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unsigned char save_lcr, save_mcr;
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unsigned long flags;
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if (!up->port.iobase && !up->port.mapbase && !up->port.membase)
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return;
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DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04x, 0x%08lx): ",
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up->port.line, up->port.iobase, up->port.membase);
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/*
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* We really do need global IRQs disabled here - we're going to
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* be frobbing the chips IRQ enable register to see if it exists.
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*/
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spin_lock_irqsave(&up->port.lock, flags);
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// save_flags(flags); cli();
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save_mcr = serial_in(up, UART_MCR);
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save_lcr = serial_in(up, UART_LCR);
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up->port.type = PORT_16550A;
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serial_outp(up, UART_LCR, save_lcr);
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up->port.fifosize = uart_config[up->port.type].dfl_xmit_fifo_size;
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if (up->port.type == PORT_UNKNOWN)
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goto out;
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/*
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* Reset the UART.
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*/
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serial_outp(up, UART_MCR, save_mcr);
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serial_outp(up, UART_FCR, (UART_FCR_ENABLE_FIFO |
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UART_FCR_CLEAR_RCVR |
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UART_FCR_CLEAR_XMIT));
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serial_outp(up, UART_FCR, 0);
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(void)serial_in(up, UART_RX);
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serial_outp(up, UART_IER, 0);
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out:
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spin_unlock_irqrestore(&up->port.lock, flags);
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// restore_flags(flags);
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DEBUG_AUTOCONF("type=%s\n", uart_config[up->port.type].name);
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}
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static void serial8250_stop_tx(struct uart_port *port)
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{
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struct uart_8250_port *up = (struct uart_8250_port *)port;
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if (up->ier & UART_IER_THRI) {
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up->ier &= ~UART_IER_THRI;
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serial_out(up, UART_IER, up->ier);
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}
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}
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static void serial8250_start_tx(struct uart_port *port)
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{
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struct uart_8250_port *up = (struct uart_8250_port *)port;
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if (!(up->ier & UART_IER_THRI)) {
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up->ier |= UART_IER_THRI;
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serial_out(up, UART_IER, up->ier);
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}
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}
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static void serial8250_stop_rx(struct uart_port *port)
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{
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struct uart_8250_port *up = (struct uart_8250_port *)port;
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up->ier &= ~UART_IER_RLSI;
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up->port.read_status_mask &= ~UART_LSR_DR;
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serial_out(up, UART_IER, up->ier);
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}
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static void serial8250_enable_ms(struct uart_port *port)
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{
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struct uart_8250_port *up = (struct uart_8250_port *)port;
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up->ier |= UART_IER_MSI;
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serial_out(up, UART_IER, up->ier);
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}
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static _INLINE_ void
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receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs)
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{
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struct tty_struct *tty = up->port.info->tty;
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unsigned char ch, flag;
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int max_count = 256;
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do {
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ch = serial_inp(up, UART_RX);
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flag = TTY_NORMAL;
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up->port.icount.rx++;
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if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
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UART_LSR_FE | UART_LSR_OE))) {
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/*
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* For statistics only
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*/
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if (*status & UART_LSR_BI) {
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*status &= ~(UART_LSR_FE | UART_LSR_PE);
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up->port.icount.brk++;
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/*
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* We do the SysRQ and SAK checking
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* here because otherwise the break
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* may get masked by ignore_status_mask
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* or read_status_mask.
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*/
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if (uart_handle_break(&up->port))
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goto ignore_char;
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} else if (*status & UART_LSR_PE)
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up->port.icount.parity++;
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else if (*status & UART_LSR_FE)
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up->port.icount.frame++;
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if (*status & UART_LSR_OE)
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up->port.icount.overrun++;
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/*
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* Mask off conditions which should be ingored.
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*/
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*status &= up->port.read_status_mask;
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#ifdef CONFIG_SERIAL_AU1X00_CONSOLE
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if (up->port.line == up->port.cons->index) {
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/* Recover the break flag from console xmit */
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*status |= up->lsr_break_flag;
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up->lsr_break_flag = 0;
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}
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#endif
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if (*status & UART_LSR_BI) {
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DEBUG_INTR("handling break....");
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flag = TTY_BREAK;
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} else if (*status & UART_LSR_PE)
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flag = TTY_PARITY;
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else if (*status & UART_LSR_FE)
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flag = TTY_FRAME;
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}
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if (uart_handle_sysrq_char(&up->port, ch, regs))
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goto ignore_char;
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if ((*status & up->port.ignore_status_mask) == 0)
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tty_insert_flip_char(tty, ch, flag);
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if (*status & UART_LSR_OE)
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/*
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* Overrun is special, since it's reported
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* immediately, and doesn't affect the current
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* character.
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*/
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tty_insert_flip_char(tty, 0, TTY_OVERRUN);
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}
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ignore_char:
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*status = serial_inp(up, UART_LSR);
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} while ((*status & UART_LSR_DR) && (max_count-- > 0));
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spin_unlock(&up->port.lock);
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tty_flip_buffer_push(tty);
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spin_lock(&up->port.lock);
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}
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static _INLINE_ void transmit_chars(struct uart_8250_port *up)
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{
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struct circ_buf *xmit = &up->port.info->xmit;
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int count;
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if (up->port.x_char) {
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serial_outp(up, UART_TX, up->port.x_char);
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up->port.icount.tx++;
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up->port.x_char = 0;
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return;
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}
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if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
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serial8250_stop_tx(&up->port);
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return;
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}
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count = up->port.fifosize;
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do {
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serial_out(up, UART_TX, xmit->buf[xmit->tail]);
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xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
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up->port.icount.tx++;
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if (uart_circ_empty(xmit))
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break;
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} while (--count > 0);
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if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
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uart_write_wakeup(&up->port);
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DEBUG_INTR("THRE...");
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if (uart_circ_empty(xmit))
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serial8250_stop_tx(&up->port);
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}
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static _INLINE_ void check_modem_status(struct uart_8250_port *up)
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{
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int status;
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status = serial_in(up, UART_MSR);
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if ((status & UART_MSR_ANY_DELTA) == 0)
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return;
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if (status & UART_MSR_TERI)
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up->port.icount.rng++;
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if (status & UART_MSR_DDSR)
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up->port.icount.dsr++;
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if (status & UART_MSR_DDCD)
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uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
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if (status & UART_MSR_DCTS)
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uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
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wake_up_interruptible(&up->port.info->delta_msr_wait);
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}
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/*
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* This handles the interrupt from one port.
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*/
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static inline void
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serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs)
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{
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unsigned int status = serial_inp(up, UART_LSR);
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DEBUG_INTR("status = %x...", status);
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if (status & UART_LSR_DR)
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receive_chars(up, &status, regs);
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check_modem_status(up);
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if (status & UART_LSR_THRE)
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transmit_chars(up);
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}
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/*
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* This is the serial driver's interrupt routine.
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*
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* Arjan thinks the old way was overly complex, so it got simplified.
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* Alan disagrees, saying that need the complexity to handle the weird
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* nature of ISA shared interrupts. (This is a special exception.)
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*
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* In order to handle ISA shared interrupts properly, we need to check
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* that all ports have been serviced, and therefore the ISA interrupt
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* line has been de-asserted.
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*
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* This means we need to loop through all ports. checking that they
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* don't have an interrupt pending.
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*/
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static irqreturn_t serial8250_interrupt(int irq, void *dev_id, struct pt_regs *regs)
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{
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struct irq_info *i = dev_id;
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struct list_head *l, *end = NULL;
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int pass_counter = 0;
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DEBUG_INTR("serial8250_interrupt(%d)...", irq);
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spin_lock(&i->lock);
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l = i->head;
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do {
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struct uart_8250_port *up;
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unsigned int iir;
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up = list_entry(l, struct uart_8250_port, list);
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iir = serial_in(up, UART_IIR);
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if (!(iir & UART_IIR_NO_INT)) {
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spin_lock(&up->port.lock);
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serial8250_handle_port(up, regs);
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spin_unlock(&up->port.lock);
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end = NULL;
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} else if (end == NULL)
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end = l;
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l = l->next;
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if (l == i->head && pass_counter++ > PASS_LIMIT) {
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/* If we hit this, we're dead. */
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printk(KERN_ERR "serial8250: too much work for "
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"irq%d\n", irq);
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break;
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}
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} while (l != end);
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|
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spin_unlock(&i->lock);
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|
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DEBUG_INTR("end.\n");
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/* FIXME! Was it really ours? */
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return IRQ_HANDLED;
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}
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|
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/*
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* To support ISA shared interrupts, we need to have one interrupt
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* handler that ensures that the IRQ line has been deasserted
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* before returning. Failing to do this will result in the IRQ
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* line being stuck active, and, since ISA irqs are edge triggered,
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* no more IRQs will be seen.
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*/
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static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
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{
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spin_lock_irq(&i->lock);
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if (!list_empty(i->head)) {
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if (i->head == &up->list)
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i->head = i->head->next;
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list_del(&up->list);
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} else {
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BUG_ON(i->head != &up->list);
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i->head = NULL;
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}
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spin_unlock_irq(&i->lock);
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}
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|
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static int serial_link_irq_chain(struct uart_8250_port *up)
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{
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struct irq_info *i = irq_lists + up->port.irq;
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int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? SA_SHIRQ : 0;
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spin_lock_irq(&i->lock);
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if (i->head) {
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list_add(&up->list, i->head);
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spin_unlock_irq(&i->lock);
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ret = 0;
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} else {
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INIT_LIST_HEAD(&up->list);
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i->head = &up->list;
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spin_unlock_irq(&i->lock);
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|
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ret = request_irq(up->port.irq, serial8250_interrupt,
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irq_flags, "serial", i);
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if (ret < 0)
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serial_do_unlink(i, up);
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}
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|
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return ret;
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}
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|
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static void serial_unlink_irq_chain(struct uart_8250_port *up)
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{
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struct irq_info *i = irq_lists + up->port.irq;
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|
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BUG_ON(i->head == NULL);
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|
|
if (list_empty(i->head))
|
|
free_irq(up->port.irq, i);
|
|
|
|
serial_do_unlink(i, up);
|
|
}
|
|
|
|
/*
|
|
* This function is used to handle ports that do not have an
|
|
* interrupt. This doesn't work very well for 16450's, but gives
|
|
* barely passable results for a 16550A. (Although at the expense
|
|
* of much CPU overhead).
|
|
*/
|
|
static void serial8250_timeout(unsigned long data)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)data;
|
|
unsigned int timeout;
|
|
unsigned int iir;
|
|
|
|
iir = serial_in(up, UART_IIR);
|
|
if (!(iir & UART_IIR_NO_INT)) {
|
|
spin_lock(&up->port.lock);
|
|
serial8250_handle_port(up, NULL);
|
|
spin_unlock(&up->port.lock);
|
|
}
|
|
|
|
timeout = up->port.timeout;
|
|
timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
|
|
mod_timer(&up->timer, jiffies + timeout);
|
|
}
|
|
|
|
static unsigned int serial8250_tx_empty(struct uart_port *port)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
unsigned long flags;
|
|
unsigned int ret;
|
|
|
|
spin_lock_irqsave(&up->port.lock, flags);
|
|
ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
|
|
spin_unlock_irqrestore(&up->port.lock, flags);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static unsigned int serial8250_get_mctrl(struct uart_port *port)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
unsigned char status;
|
|
unsigned int ret;
|
|
|
|
status = serial_in(up, UART_MSR);
|
|
|
|
ret = 0;
|
|
if (status & UART_MSR_DCD)
|
|
ret |= TIOCM_CAR;
|
|
if (status & UART_MSR_RI)
|
|
ret |= TIOCM_RNG;
|
|
if (status & UART_MSR_DSR)
|
|
ret |= TIOCM_DSR;
|
|
if (status & UART_MSR_CTS)
|
|
ret |= TIOCM_CTS;
|
|
return ret;
|
|
}
|
|
|
|
static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
unsigned char mcr = 0;
|
|
|
|
if (mctrl & TIOCM_RTS)
|
|
mcr |= UART_MCR_RTS;
|
|
if (mctrl & TIOCM_DTR)
|
|
mcr |= UART_MCR_DTR;
|
|
if (mctrl & TIOCM_OUT1)
|
|
mcr |= UART_MCR_OUT1;
|
|
if (mctrl & TIOCM_OUT2)
|
|
mcr |= UART_MCR_OUT2;
|
|
if (mctrl & TIOCM_LOOP)
|
|
mcr |= UART_MCR_LOOP;
|
|
|
|
mcr = (mcr & up->mcr_mask) | up->mcr_force;
|
|
|
|
serial_out(up, UART_MCR, mcr);
|
|
}
|
|
|
|
static void serial8250_break_ctl(struct uart_port *port, int break_state)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&up->port.lock, flags);
|
|
if (break_state == -1)
|
|
up->lcr |= UART_LCR_SBC;
|
|
else
|
|
up->lcr &= ~UART_LCR_SBC;
|
|
serial_out(up, UART_LCR, up->lcr);
|
|
spin_unlock_irqrestore(&up->port.lock, flags);
|
|
}
|
|
|
|
static int serial8250_startup(struct uart_port *port)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
unsigned long flags;
|
|
int retval;
|
|
|
|
/*
|
|
* Clear the FIFO buffers and disable them.
|
|
* (they will be reeanbled in set_termios())
|
|
*/
|
|
if (uart_config[up->port.type].flags & UART_CLEAR_FIFO) {
|
|
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
|
|
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
|
|
UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
|
|
serial_outp(up, UART_FCR, 0);
|
|
}
|
|
|
|
/*
|
|
* Clear the interrupt registers.
|
|
*/
|
|
(void) serial_inp(up, UART_LSR);
|
|
(void) serial_inp(up, UART_RX);
|
|
(void) serial_inp(up, UART_IIR);
|
|
(void) serial_inp(up, UART_MSR);
|
|
|
|
/*
|
|
* At this point, there's no way the LSR could still be 0xff;
|
|
* if it is, then bail out, because there's likely no UART
|
|
* here.
|
|
*/
|
|
if (!(up->port.flags & UPF_BUGGY_UART) &&
|
|
(serial_inp(up, UART_LSR) == 0xff)) {
|
|
printk("ttyS%d: LSR safety check engaged!\n", up->port.line);
|
|
return -ENODEV;
|
|
}
|
|
|
|
retval = serial_link_irq_chain(up);
|
|
if (retval)
|
|
return retval;
|
|
|
|
/*
|
|
* Now, initialize the UART
|
|
*/
|
|
serial_outp(up, UART_LCR, UART_LCR_WLEN8);
|
|
|
|
spin_lock_irqsave(&up->port.lock, flags);
|
|
if (up->port.flags & UPF_FOURPORT) {
|
|
if (!is_real_interrupt(up->port.irq))
|
|
up->port.mctrl |= TIOCM_OUT1;
|
|
} else
|
|
/*
|
|
* Most PC uarts need OUT2 raised to enable interrupts.
|
|
*/
|
|
if (is_real_interrupt(up->port.irq))
|
|
up->port.mctrl |= TIOCM_OUT2;
|
|
|
|
serial8250_set_mctrl(&up->port, up->port.mctrl);
|
|
spin_unlock_irqrestore(&up->port.lock, flags);
|
|
|
|
/*
|
|
* Finally, enable interrupts. Note: Modem status interrupts
|
|
* are set via set_termios(), which will be occurring imminently
|
|
* anyway, so we don't enable them here.
|
|
*/
|
|
up->ier = UART_IER_RLSI | UART_IER_RDI;
|
|
serial_outp(up, UART_IER, up->ier);
|
|
|
|
if (up->port.flags & UPF_FOURPORT) {
|
|
unsigned int icp;
|
|
/*
|
|
* Enable interrupts on the AST Fourport board
|
|
*/
|
|
icp = (up->port.iobase & 0xfe0) | 0x01f;
|
|
outb_p(0x80, icp);
|
|
(void) inb_p(icp);
|
|
}
|
|
|
|
/*
|
|
* And clear the interrupt registers again for luck.
|
|
*/
|
|
(void) serial_inp(up, UART_LSR);
|
|
(void) serial_inp(up, UART_RX);
|
|
(void) serial_inp(up, UART_IIR);
|
|
(void) serial_inp(up, UART_MSR);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void serial8250_shutdown(struct uart_port *port)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
unsigned long flags;
|
|
|
|
/*
|
|
* Disable interrupts from this port
|
|
*/
|
|
up->ier = 0;
|
|
serial_outp(up, UART_IER, 0);
|
|
|
|
spin_lock_irqsave(&up->port.lock, flags);
|
|
if (up->port.flags & UPF_FOURPORT) {
|
|
/* reset interrupts on the AST Fourport board */
|
|
inb((up->port.iobase & 0xfe0) | 0x1f);
|
|
up->port.mctrl |= TIOCM_OUT1;
|
|
} else
|
|
up->port.mctrl &= ~TIOCM_OUT2;
|
|
|
|
serial8250_set_mctrl(&up->port, up->port.mctrl);
|
|
spin_unlock_irqrestore(&up->port.lock, flags);
|
|
|
|
/*
|
|
* Disable break condition and FIFOs
|
|
*/
|
|
serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC);
|
|
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
|
|
UART_FCR_CLEAR_RCVR |
|
|
UART_FCR_CLEAR_XMIT);
|
|
serial_outp(up, UART_FCR, 0);
|
|
|
|
/*
|
|
* Read data port to reset things, and then unlink from
|
|
* the IRQ chain.
|
|
*/
|
|
(void) serial_in(up, UART_RX);
|
|
|
|
if (!is_real_interrupt(up->port.irq))
|
|
del_timer_sync(&up->timer);
|
|
else
|
|
serial_unlink_irq_chain(up);
|
|
}
|
|
|
|
static unsigned int serial8250_get_divisor(struct uart_port *port, unsigned int baud)
|
|
{
|
|
unsigned int quot;
|
|
|
|
/*
|
|
* Handle magic divisors for baud rates above baud_base on
|
|
* SMSC SuperIO chips.
|
|
*/
|
|
if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
|
|
baud == (port->uartclk/4))
|
|
quot = 0x8001;
|
|
else if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
|
|
baud == (port->uartclk/8))
|
|
quot = 0x8002;
|
|
else
|
|
quot = uart_get_divisor(port, baud);
|
|
|
|
return quot;
|
|
}
|
|
|
|
static void
|
|
serial8250_set_termios(struct uart_port *port, struct termios *termios,
|
|
struct termios *old)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
unsigned char cval, fcr = 0;
|
|
unsigned long flags;
|
|
unsigned int baud, quot;
|
|
|
|
switch (termios->c_cflag & CSIZE) {
|
|
case CS5:
|
|
cval = UART_LCR_WLEN5;
|
|
break;
|
|
case CS6:
|
|
cval = UART_LCR_WLEN6;
|
|
break;
|
|
case CS7:
|
|
cval = UART_LCR_WLEN7;
|
|
break;
|
|
default:
|
|
case CS8:
|
|
cval = UART_LCR_WLEN8;
|
|
break;
|
|
}
|
|
|
|
if (termios->c_cflag & CSTOPB)
|
|
cval |= UART_LCR_STOP;
|
|
if (termios->c_cflag & PARENB)
|
|
cval |= UART_LCR_PARITY;
|
|
if (!(termios->c_cflag & PARODD))
|
|
cval |= UART_LCR_EPAR;
|
|
#ifdef CMSPAR
|
|
if (termios->c_cflag & CMSPAR)
|
|
cval |= UART_LCR_SPAR;
|
|
#endif
|
|
|
|
/*
|
|
* Ask the core to calculate the divisor for us.
|
|
*/
|
|
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
|
|
quot = serial8250_get_divisor(port, baud);
|
|
quot = 0x35; /* FIXME */
|
|
|
|
/*
|
|
* Work around a bug in the Oxford Semiconductor 952 rev B
|
|
* chip which causes it to seriously miscalculate baud rates
|
|
* when DLL is 0.
|
|
*/
|
|
if ((quot & 0xff) == 0 && up->port.type == PORT_16C950 &&
|
|
up->rev == 0x5201)
|
|
quot ++;
|
|
|
|
if (uart_config[up->port.type].flags & UART_USE_FIFO) {
|
|
if (baud < 2400)
|
|
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_1;
|
|
else
|
|
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_8;
|
|
}
|
|
|
|
/*
|
|
* Ok, we're now changing the port state. Do it with
|
|
* interrupts disabled.
|
|
*/
|
|
spin_lock_irqsave(&up->port.lock, flags);
|
|
|
|
/*
|
|
* Update the per-port timeout.
|
|
*/
|
|
uart_update_timeout(port, termios->c_cflag, baud);
|
|
|
|
up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
|
|
if (termios->c_iflag & INPCK)
|
|
up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
|
|
if (termios->c_iflag & (BRKINT | PARMRK))
|
|
up->port.read_status_mask |= UART_LSR_BI;
|
|
|
|
/*
|
|
* Characteres to ignore
|
|
*/
|
|
up->port.ignore_status_mask = 0;
|
|
if (termios->c_iflag & IGNPAR)
|
|
up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
|
|
if (termios->c_iflag & IGNBRK) {
|
|
up->port.ignore_status_mask |= UART_LSR_BI;
|
|
/*
|
|
* If we're ignoring parity and break indicators,
|
|
* ignore overruns too (for real raw support).
|
|
*/
|
|
if (termios->c_iflag & IGNPAR)
|
|
up->port.ignore_status_mask |= UART_LSR_OE;
|
|
}
|
|
|
|
/*
|
|
* ignore all characters if CREAD is not set
|
|
*/
|
|
if ((termios->c_cflag & CREAD) == 0)
|
|
up->port.ignore_status_mask |= UART_LSR_DR;
|
|
|
|
/*
|
|
* CTS flow control flag and modem status interrupts
|
|
*/
|
|
up->ier &= ~UART_IER_MSI;
|
|
if (UART_ENABLE_MS(&up->port, termios->c_cflag))
|
|
up->ier |= UART_IER_MSI;
|
|
|
|
serial_out(up, UART_IER, up->ier);
|
|
serial_outp(up, 0x28, quot & 0xffff);
|
|
up->lcr = cval; /* Save LCR */
|
|
if (up->port.type != PORT_16750) {
|
|
if (fcr & UART_FCR_ENABLE_FIFO) {
|
|
/* emulated UARTs (Lucent Venus 167x) need two steps */
|
|
serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
|
|
}
|
|
serial_outp(up, UART_FCR, fcr); /* set fcr */
|
|
}
|
|
spin_unlock_irqrestore(&up->port.lock, flags);
|
|
}
|
|
|
|
static void
|
|
serial8250_pm(struct uart_port *port, unsigned int state,
|
|
unsigned int oldstate)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
if (state) {
|
|
/* sleep */
|
|
if (up->pm)
|
|
up->pm(port, state, oldstate);
|
|
} else {
|
|
/* wake */
|
|
if (up->pm)
|
|
up->pm(port, state, oldstate);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Resource handling. This is complicated by the fact that resources
|
|
* depend on the port type. Maybe we should be claiming the standard
|
|
* 8250 ports, and then trying to get other resources as necessary?
|
|
*/
|
|
static int
|
|
serial8250_request_std_resource(struct uart_8250_port *up, struct resource **res)
|
|
{
|
|
unsigned int size = 8 << up->port.regshift;
|
|
int ret = 0;
|
|
|
|
switch (up->port.iotype) {
|
|
case UPIO_MEM:
|
|
if (up->port.mapbase) {
|
|
*res = request_mem_region(up->port.mapbase, size, "serial");
|
|
if (!*res)
|
|
ret = -EBUSY;
|
|
}
|
|
break;
|
|
|
|
case UPIO_HUB6:
|
|
case UPIO_PORT:
|
|
*res = request_region(up->port.iobase, size, "serial");
|
|
if (!*res)
|
|
ret = -EBUSY;
|
|
break;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
|
|
static void serial8250_release_port(struct uart_port *port)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
unsigned long start, offset = 0, size = 0;
|
|
|
|
size <<= up->port.regshift;
|
|
|
|
switch (up->port.iotype) {
|
|
case UPIO_MEM:
|
|
if (up->port.mapbase) {
|
|
/*
|
|
* Unmap the area.
|
|
*/
|
|
iounmap(up->port.membase);
|
|
up->port.membase = NULL;
|
|
|
|
start = up->port.mapbase;
|
|
|
|
if (size)
|
|
release_mem_region(start + offset, size);
|
|
release_mem_region(start, 8 << up->port.regshift);
|
|
}
|
|
break;
|
|
|
|
case UPIO_HUB6:
|
|
case UPIO_PORT:
|
|
start = up->port.iobase;
|
|
|
|
if (size)
|
|
release_region(start + offset, size);
|
|
release_region(start + offset, 8 << up->port.regshift);
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
static int serial8250_request_port(struct uart_port *port)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
struct resource *res = NULL, *res_rsa = NULL;
|
|
int ret = 0;
|
|
|
|
ret = serial8250_request_std_resource(up, &res);
|
|
|
|
/*
|
|
* If we have a mapbase, then request that as well.
|
|
*/
|
|
if (ret == 0 && up->port.flags & UPF_IOREMAP) {
|
|
int size = res->end - res->start + 1;
|
|
|
|
up->port.membase = ioremap(up->port.mapbase, size);
|
|
if (!up->port.membase)
|
|
ret = -ENOMEM;
|
|
}
|
|
|
|
if (ret < 0) {
|
|
if (res_rsa)
|
|
release_resource(res_rsa);
|
|
if (res)
|
|
release_resource(res);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void serial8250_config_port(struct uart_port *port, int flags)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
struct resource *res_std = NULL, *res_rsa = NULL;
|
|
int probeflags = PROBE_ANY;
|
|
|
|
probeflags &= ~PROBE_RSA;
|
|
|
|
if (flags & UART_CONFIG_TYPE)
|
|
autoconfig(up, probeflags);
|
|
|
|
/*
|
|
* If the port wasn't an RSA port, release the resource.
|
|
*/
|
|
if (up->port.type != PORT_RSA && res_rsa)
|
|
release_resource(res_rsa);
|
|
|
|
if (up->port.type == PORT_UNKNOWN && res_std)
|
|
release_resource(res_std);
|
|
}
|
|
|
|
static int
|
|
serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
|
|
{
|
|
if (ser->irq >= NR_IRQS || ser->irq < 0 ||
|
|
ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
|
|
ser->type > PORT_MAX_8250 || ser->type == PORT_CIRRUS ||
|
|
ser->type == PORT_STARTECH)
|
|
return -EINVAL;
|
|
return 0;
|
|
}
|
|
|
|
static const char *
|
|
serial8250_type(struct uart_port *port)
|
|
{
|
|
int type = port->type;
|
|
|
|
if (type >= ARRAY_SIZE(uart_config))
|
|
type = 0;
|
|
return uart_config[type].name;
|
|
}
|
|
|
|
static struct uart_ops serial8250_pops = {
|
|
.tx_empty = serial8250_tx_empty,
|
|
.set_mctrl = serial8250_set_mctrl,
|
|
.get_mctrl = serial8250_get_mctrl,
|
|
.stop_tx = serial8250_stop_tx,
|
|
.start_tx = serial8250_start_tx,
|
|
.stop_rx = serial8250_stop_rx,
|
|
.enable_ms = serial8250_enable_ms,
|
|
.break_ctl = serial8250_break_ctl,
|
|
.startup = serial8250_startup,
|
|
.shutdown = serial8250_shutdown,
|
|
.set_termios = serial8250_set_termios,
|
|
.pm = serial8250_pm,
|
|
.type = serial8250_type,
|
|
.release_port = serial8250_release_port,
|
|
.request_port = serial8250_request_port,
|
|
.config_port = serial8250_config_port,
|
|
.verify_port = serial8250_verify_port,
|
|
};
|
|
|
|
static struct uart_8250_port serial8250_ports[UART_NR];
|
|
|
|
static void __init serial8250_isa_init_ports(void)
|
|
{
|
|
struct uart_8250_port *up;
|
|
static int first = 1;
|
|
int i;
|
|
|
|
if (!first)
|
|
return;
|
|
first = 0;
|
|
|
|
for (i = 0, up = serial8250_ports; i < ARRAY_SIZE(old_serial_port);
|
|
i++, up++) {
|
|
up->port.iobase = old_serial_port[i].port;
|
|
up->port.irq = old_serial_port[i].irq;
|
|
up->port.uartclk = get_au1x00_uart_baud_base();
|
|
up->port.flags = old_serial_port[i].flags;
|
|
up->port.hub6 = old_serial_port[i].hub6;
|
|
up->port.membase = old_serial_port[i].iomem_base;
|
|
up->port.iotype = old_serial_port[i].io_type;
|
|
up->port.regshift = old_serial_port[i].iomem_reg_shift;
|
|
up->port.ops = &serial8250_pops;
|
|
}
|
|
}
|
|
|
|
static void __init serial8250_register_ports(struct uart_driver *drv)
|
|
{
|
|
int i;
|
|
|
|
serial8250_isa_init_ports();
|
|
|
|
for (i = 0; i < UART_NR; i++) {
|
|
struct uart_8250_port *up = &serial8250_ports[i];
|
|
|
|
up->port.line = i;
|
|
up->port.ops = &serial8250_pops;
|
|
init_timer(&up->timer);
|
|
up->timer.function = serial8250_timeout;
|
|
|
|
/*
|
|
* ALPHA_KLUDGE_MCR needs to be killed.
|
|
*/
|
|
up->mcr_mask = ~ALPHA_KLUDGE_MCR;
|
|
up->mcr_force = ALPHA_KLUDGE_MCR;
|
|
|
|
uart_add_one_port(drv, &up->port);
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_SERIAL_AU1X00_CONSOLE
|
|
|
|
#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
|
|
|
|
/*
|
|
* Wait for transmitter & holding register to empty
|
|
*/
|
|
static inline void wait_for_xmitr(struct uart_8250_port *up)
|
|
{
|
|
unsigned int status, tmout = 10000;
|
|
|
|
/* Wait up to 10ms for the character(s) to be sent. */
|
|
do {
|
|
status = serial_in(up, UART_LSR);
|
|
|
|
if (status & UART_LSR_BI)
|
|
up->lsr_break_flag = UART_LSR_BI;
|
|
|
|
if (--tmout == 0)
|
|
break;
|
|
udelay(1);
|
|
} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
|
|
|
|
/* Wait up to 1s for flow control if necessary */
|
|
if (up->port.flags & UPF_CONS_FLOW) {
|
|
tmout = 1000000;
|
|
while (--tmout &&
|
|
((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
|
|
udelay(1);
|
|
}
|
|
}
|
|
|
|
static void au1x00_console_putchar(struct uart_port *port, int ch)
|
|
{
|
|
struct uart_8250_port *up = (struct uart_8250_port *)port;
|
|
|
|
wait_for_xmitr(up);
|
|
serial_out(up, UART_TX, ch);
|
|
}
|
|
|
|
/*
|
|
* Print a string to the serial port trying not to disturb
|
|
* any possible real use of the port...
|
|
*
|
|
* The console_lock must be held when we get here.
|
|
*/
|
|
static void
|
|
serial8250_console_write(struct console *co, const char *s, unsigned int count)
|
|
{
|
|
struct uart_8250_port *up = &serial8250_ports[co->index];
|
|
unsigned int ier;
|
|
|
|
/*
|
|
* First save the UER then disable the interrupts
|
|
*/
|
|
ier = serial_in(up, UART_IER);
|
|
serial_out(up, UART_IER, 0);
|
|
|
|
uart_console_write(&up->port, s, count, au1x00_console_putchar);
|
|
|
|
/*
|
|
* Finally, wait for transmitter to become empty
|
|
* and restore the IER
|
|
*/
|
|
wait_for_xmitr(up);
|
|
serial_out(up, UART_IER, ier);
|
|
}
|
|
|
|
static int __init serial8250_console_setup(struct console *co, char *options)
|
|
{
|
|
struct uart_port *port;
|
|
int baud = 9600;
|
|
int bits = 8;
|
|
int parity = 'n';
|
|
int flow = 'n';
|
|
|
|
/*
|
|
* Check whether an invalid uart number has been specified, and
|
|
* if so, search for the first available port that does have
|
|
* console support.
|
|
*/
|
|
if (co->index >= UART_NR)
|
|
co->index = 0;
|
|
port = &serial8250_ports[co->index].port;
|
|
|
|
/*
|
|
* Temporary fix.
|
|
*/
|
|
spin_lock_init(&port->lock);
|
|
|
|
if (options)
|
|
uart_parse_options(options, &baud, &parity, &bits, &flow);
|
|
|
|
return uart_set_options(port, co, baud, parity, bits, flow);
|
|
}
|
|
|
|
extern struct uart_driver serial8250_reg;
|
|
static struct console serial8250_console = {
|
|
.name = "ttyS",
|
|
.write = serial8250_console_write,
|
|
.device = uart_console_device,
|
|
.setup = serial8250_console_setup,
|
|
.flags = CON_PRINTBUFFER,
|
|
.index = -1,
|
|
.data = &serial8250_reg,
|
|
};
|
|
|
|
static int __init serial8250_console_init(void)
|
|
{
|
|
serial8250_isa_init_ports();
|
|
register_console(&serial8250_console);
|
|
return 0;
|
|
}
|
|
console_initcall(serial8250_console_init);
|
|
|
|
#define SERIAL8250_CONSOLE &serial8250_console
|
|
#else
|
|
#define SERIAL8250_CONSOLE NULL
|
|
#endif
|
|
|
|
static struct uart_driver serial8250_reg = {
|
|
.owner = THIS_MODULE,
|
|
.driver_name = "serial",
|
|
.devfs_name = "tts/",
|
|
.dev_name = "ttyS",
|
|
.major = TTY_MAJOR,
|
|
.minor = 64,
|
|
.nr = UART_NR,
|
|
.cons = SERIAL8250_CONSOLE,
|
|
};
|
|
|
|
int __init early_serial_setup(struct uart_port *port)
|
|
{
|
|
serial8250_isa_init_ports();
|
|
serial8250_ports[port->line].port = *port;
|
|
serial8250_ports[port->line].port.ops = &serial8250_pops;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* serial8250_suspend_port - suspend one serial port
|
|
* @line: serial line number
|
|
* @level: the level of port suspension, as per uart_suspend_port
|
|
*
|
|
* Suspend one serial port.
|
|
*/
|
|
void serial8250_suspend_port(int line)
|
|
{
|
|
uart_suspend_port(&serial8250_reg, &serial8250_ports[line].port);
|
|
}
|
|
|
|
/**
|
|
* serial8250_resume_port - resume one serial port
|
|
* @line: serial line number
|
|
* @level: the level of port resumption, as per uart_resume_port
|
|
*
|
|
* Resume one serial port.
|
|
*/
|
|
void serial8250_resume_port(int line)
|
|
{
|
|
uart_resume_port(&serial8250_reg, &serial8250_ports[line].port);
|
|
}
|
|
|
|
static int __init serial8250_init(void)
|
|
{
|
|
int ret, i;
|
|
|
|
printk(KERN_INFO "Serial: Au1x00 driver\n");
|
|
|
|
for (i = 0; i < NR_IRQS; i++)
|
|
spin_lock_init(&irq_lists[i].lock);
|
|
|
|
ret = uart_register_driver(&serial8250_reg);
|
|
if (ret >= 0)
|
|
serial8250_register_ports(&serial8250_reg);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void __exit serial8250_exit(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < UART_NR; i++)
|
|
uart_remove_one_port(&serial8250_reg, &serial8250_ports[i].port);
|
|
|
|
uart_unregister_driver(&serial8250_reg);
|
|
}
|
|
|
|
module_init(serial8250_init);
|
|
module_exit(serial8250_exit);
|
|
|
|
EXPORT_SYMBOL(serial8250_suspend_port);
|
|
EXPORT_SYMBOL(serial8250_resume_port);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_DESCRIPTION("Au1x00 serial driver\n");
|