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/*
* linux/drivers/char/serial_amba.c
*
* Driver for AMBA serial ports
*
* Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
*
* Copyright 1999 ARM Limited
* Copyright (C) 2000 Deep Blue Solutions Ltd.
*
* 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
*
*
* This is a generic driver for ARM AMBA-type serial ports. They
* have a lot of 16550-like features, but are not register compatable.
* Note that although they do have CTS, DCD and DSR inputs, they do
* not have an RI input, nor do they have DTR or RTS outputs. If
* required, these have to be supplied via some other means (eg, GPIO)
* and hooked into this driver.
*
* This could very easily become a generic serial driver for dumb UARTs
* (eg, {82,16x}50, 21285, SA1100).
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/circ_buf.h>
#include <linux/serial.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/bitops.h>
#include <asm/hardware/serial_amba.h>
#define SERIAL_AMBA_NAME "ttyAM"
#define SERIAL_AMBA_MAJOR 204
#define SERIAL_AMBA_MINOR 16
#define SERIAL_AMBA_NR 2
#define CALLOUT_AMBA_NAME "cuaam"
#define CALLOUT_AMBA_MAJOR 205
#define CALLOUT_AMBA_MINOR 16
#define CALLOUT_AMBA_NR SERIAL_AMBA_NR
#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif
#define DEBUG 0
#define DEBUG_LEDS 0
#if DEBUG_LEDS
extern int get_leds(void);
extern int set_leds(int);
#endif
/*
* Access routines for the AMBA UARTs
*/
#define UART_GET_INT_STATUS(p) IO_READ((p)->uart_base + AMBA_UARTIIR)
#define UART_GET_FR(p) IO_READ((p)->uart_base + AMBA_UARTFR)
#define UART_GET_CHAR(p) IO_READ((p)->uart_base + AMBA_UARTDR)
#define UART_PUT_CHAR(p, c) IO_WRITE((p)->uart_base + AMBA_UARTDR, (c))
#define UART_GET_RSR(p) IO_READ((p)->uart_base + AMBA_UARTRSR)
#define UART_GET_CR(p) IO_READ((p)->uart_base + AMBA_UARTCR)
#define UART_PUT_CR(p,c) IO_WRITE((p)->uart_base + AMBA_UARTCR, (c))
#define UART_GET_LCRL(p) IO_READ((p)->uart_base + AMBA_UARTLCR_L)
#define UART_PUT_LCRL(p,c) IO_WRITE((p)->uart_base + AMBA_UARTLCR_L, (c))
#define UART_GET_LCRM(p) IO_READ((p)->uart_base + AMBA_UARTLCR_M)
#define UART_PUT_LCRM(p,c) IO_WRITE((p)->uart_base + AMBA_UARTLCR_M, (c))
#define UART_GET_LCRH(p) IO_READ((p)->uart_base + AMBA_UARTLCR_H)
#define UART_PUT_LCRH(p,c) IO_WRITE((p)->uart_base + AMBA_UARTLCR_H, (c))
#define UART_RX_DATA(s) (((s) & AMBA_UARTFR_RXFE) == 0)
#define UART_TX_READY(s) (((s) & AMBA_UARTFR_TXFF) == 0)
#define UART_TX_EMPTY(p) ((UART_GET_FR(p) & AMBA_UARTFR_TMSK) == 0)
#define AMBA_UARTRSR_ANY (AMBA_UARTRSR_OE|AMBA_UARTRSR_BE|AMBA_UARTRSR_PE|AMBA_UARTRSR_FE)
#define AMBA_UARTFR_MODEM_ANY (AMBA_UARTFR_DCD|AMBA_UARTFR_DSR|AMBA_UARTFR_CTS)
/*
* Things needed by tty driver
*/
static struct tty_driver ambanormal_driver, ambacallout_driver;
static int ambauart_refcount;
static struct tty_struct *ambauart_table[SERIAL_AMBA_NR];
static struct termios *ambauart_termios[SERIAL_AMBA_NR];
static struct termios *ambauart_termios_locked[SERIAL_AMBA_NR];
#if defined(CONFIG_SERIAL_AMBA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
/*
* Things needed internally to this driver
*/
/*
* tmp_buf is used as a temporary buffer by serial_write. We need to
* lock it in case the copy_from_user blocks while swapping in a page,
* and some other program tries to do a serial write at the same time.
* Since the lock will only come under contention when the system is
* swapping and available memory is low, it makes sense to share one
* buffer across all the serial ports, since it significantly saves
* memory if large numbers of serial ports are open.
*/
static u_char *tmp_buf;
static DECLARE_MUTEX(tmp_buf_sem);
#define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256
#define AMBA_ISR_PASS_LIMIT 256
#define EVT_WRITE_WAKEUP 0
struct amba_icount {
__u32 cts;
__u32 dsr;
__u32 rng;
__u32 dcd;
__u32 rx;
__u32 tx;
__u32 frame;
__u32 overrun;
__u32 parity;
__u32 brk;
__u32 buf_overrun;
};
/*
* Static information about the port
*/
struct amba_port {
unsigned int uart_base;
unsigned int irq;
unsigned int uartclk;
unsigned int fifosize;
unsigned int tiocm_support;
void (*set_mctrl)(struct amba_port *, u_int mctrl);
};
/*
* This is the state information which is persistent across opens
*/
struct amba_state {
struct amba_icount icount;
unsigned int line;
unsigned int close_delay;
unsigned int closing_wait;
unsigned int custom_divisor;
unsigned int flags;
struct termios normal_termios;
struct termios callout_termios;
int count;
struct amba_info *info;
};
#define AMBA_XMIT_SIZE 1024
/*
* This is the state information which is only valid when the port is open.
*/
struct amba_info {
struct amba_port *port;
struct amba_state *state;
struct tty_struct *tty;
unsigned char x_char;
unsigned char old_status;
unsigned char read_status_mask;
unsigned char ignore_status_mask;
struct circ_buf xmit;
unsigned int flags;
#ifdef SUPPORT_SYSRQ
unsigned long sysrq;
#endif
unsigned int event;
unsigned int timeout;
unsigned int lcr_h;
unsigned int mctrl;
int blocked_open;
pid_t session;
pid_t pgrp;
struct tasklet_struct tlet;
wait_queue_head_t open_wait;
wait_queue_head_t close_wait;
wait_queue_head_t delta_msr_wait;
};
#ifdef CONFIG_SERIAL_AMBA_CONSOLE
static struct console ambauart_cons;
#endif
static void ambauart_change_speed(struct amba_info *info, struct termios *old_termios);
static void ambauart_wait_until_sent(struct tty_struct *tty, int timeout);
#if 1 //def CONFIG_SERIAL_INTEGRATOR
static void amba_set_mctrl_null(struct amba_port *port, u_int mctrl)
{
}
static struct amba_port amba_ports[SERIAL_AMBA_NR] = {
{
uart_base: IO_ADDRESS(INTEGRATOR_UART0_BASE),
irq: IRQ_UARTINT0,
uartclk: 14745600,
fifosize: 8,
set_mctrl: amba_set_mctrl_null,
},
{
uart_base: IO_ADDRESS(INTEGRATOR_UART1_BASE),
irq: IRQ_UARTINT1,
uartclk: 14745600,
fifosize: 8,
set_mctrl: amba_set_mctrl_null,
}
};
#endif
static struct amba_state amba_state[SERIAL_AMBA_NR];
static void ambauart_enable_rx_interrupt(struct amba_info *info)
{
unsigned int cr;
cr = UART_GET_CR(info->port);
cr |= AMBA_UARTCR_RIE | AMBA_UARTCR_RTIE;
UART_PUT_CR(info->port, cr);
}
static void ambauart_disable_rx_interrupt(struct amba_info *info)
{
unsigned int cr;
cr = UART_GET_CR(info->port);
cr &= ~(AMBA_UARTCR_RIE | AMBA_UARTCR_RTIE);
UART_PUT_CR(info->port, cr);
}
static void ambauart_enable_tx_interrupt(struct amba_info *info)
{
unsigned int cr;
cr = UART_GET_CR(info->port);
cr |= AMBA_UARTCR_TIE;
UART_PUT_CR(info->port, cr);
}
static void ambauart_disable_tx_interrupt(struct amba_info *info)
{
unsigned int cr;
cr = UART_GET_CR(info->port);
cr &= ~AMBA_UARTCR_TIE;
UART_PUT_CR(info->port, cr);
}
static void ambauart_stop(struct tty_struct *tty)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
save_flags(flags); cli();
ambauart_disable_tx_interrupt(info);
restore_flags(flags);
}
static void ambauart_start(struct tty_struct *tty)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
save_flags(flags); cli();
if (info->xmit.head != info->xmit.tail
&& info->xmit.buf)
ambauart_enable_tx_interrupt(info);
restore_flags(flags);
}
/*
* This routine is used by the interrupt handler to schedule
* processing in the software interrupt portion of the driver.
*/
static void ambauart_event(struct amba_info *info, int event)
{
info->event |= 1 << event;
tasklet_schedule(&info->tlet);
}
static void
#ifdef SUPPORT_SYSRQ
ambauart_rx_chars(struct amba_info *info, struct pt_regs *regs)
#else
ambauart_rx_chars(struct amba_info *info)
#endif
{
struct tty_struct *tty = info->tty;
unsigned int status, ch, rsr, flg, ignored = 0;
struct amba_icount *icount = &info->state->icount;
struct amba_port *port = info->port;
status = UART_GET_FR(port);
while (UART_RX_DATA(status)) {
ch = UART_GET_CHAR(port);
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
goto ignore_char;
icount->rx++;
flg = TTY_NORMAL;
/*
* Note that the error handling code is
* out of the main execution path
*/
rsr = UART_GET_RSR(port);
if (rsr & AMBA_UARTRSR_ANY)
goto handle_error;
#ifdef SUPPORT_SYSRQ
if (info->sysrq) {
if (ch && time_before(jiffies, info->sysrq)) {
handle_sysrq(ch, regs, NULL, NULL);
info->sysrq = 0;
goto ignore_char;
}
info->sysrq = 0;
}
#endif
error_return:
*tty->flip.flag_buf_ptr++ = flg;
*tty->flip.char_buf_ptr++ = ch;
tty->flip.count++;
ignore_char:
status = UART_GET_FR(port);
}
out:
tty_flip_buffer_push(tty);
return;
handle_error:
if (rsr & AMBA_UARTRSR_BE) {
rsr &= ~(AMBA_UARTRSR_FE | AMBA_UARTRSR_PE);
icount->brk++;
#ifdef SUPPORT_SYSRQ
if (info->state->line == ambauart_cons.index) {
if (!info->sysrq) {
info->sysrq = jiffies + HZ*5;
goto ignore_char;
}
}
#endif
} else if (rsr & AMBA_UARTRSR_PE)
icount->parity++;
else if (rsr & AMBA_UARTRSR_FE)
icount->frame++;
if (rsr & AMBA_UARTRSR_OE)
icount->overrun++;
if (rsr & info->ignore_status_mask) {
if (++ignored > 100)
goto out;
goto ignore_char;
}
rsr &= info->read_status_mask;
if (rsr & AMBA_UARTRSR_BE)
flg = TTY_BREAK;
else if (rsr & AMBA_UARTRSR_PE)
flg = TTY_PARITY;
else if (rsr & AMBA_UARTRSR_FE)
flg = TTY_FRAME;
if (rsr & AMBA_UARTRSR_OE) {
/*
* CHECK: does overrun affect the current character?
* ASSUMPTION: it does not.
*/
*tty->flip.flag_buf_ptr++ = flg;
*tty->flip.char_buf_ptr++ = ch;
tty->flip.count++;
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
goto ignore_char;
ch = 0;
flg = TTY_OVERRUN;
}
#ifdef SUPPORT_SYSRQ
info->sysrq = 0;
#endif
goto error_return;
}
static void ambauart_tx_chars(struct amba_info *info)
{
struct amba_port *port = info->port;
int count;
if (info->x_char) {
UART_PUT_CHAR(port, info->x_char);
info->state->icount.tx++;
info->x_char = 0;
return;
}
if (info->xmit.head == info->xmit.tail
|| info->tty->stopped
|| info->tty->hw_stopped) {
ambauart_disable_tx_interrupt(info);
return;
}
count = port->fifosize;
do {
UART_PUT_CHAR(port, info->xmit.buf[info->xmit.tail]);
info->xmit.tail = (info->xmit.tail + 1) & (AMBA_XMIT_SIZE - 1);
info->state->icount.tx++;
if (info->xmit.head == info->xmit.tail)
break;
} while (--count > 0);
if (CIRC_CNT(info->xmit.head,
info->xmit.tail,
AMBA_XMIT_SIZE) < WAKEUP_CHARS)
ambauart_event(info, EVT_WRITE_WAKEUP);
if (info->xmit.head == info->xmit.tail) {
ambauart_disable_tx_interrupt(info);
}
}
static void ambauart_modem_status(struct amba_info *info)
{
unsigned int status, delta;
struct amba_icount *icount = &info->state->icount;
status = UART_GET_FR(info->port) & AMBA_UARTFR_MODEM_ANY;
delta = status ^ info->old_status;
info->old_status = status;
if (!delta)
return;
if (delta & AMBA_UARTFR_DCD) {
icount->dcd++;
#ifdef CONFIG_HARD_PPS
if ((info->flags & ASYNC_HARDPPS_CD) &&
(status & AMBA_UARTFR_DCD)
hardpps();
#endif
if (info->flags & ASYNC_CHECK_CD) {
if (status & AMBA_UARTFR_DCD)
wake_up_interruptible(&info->open_wait);
else if (!((info->flags & ASYNC_CALLOUT_ACTIVE) &&
(info->flags & ASYNC_CALLOUT_NOHUP))) {
if (info->tty)
tty_hangup(info->tty);
}
}
}
if (delta & AMBA_UARTFR_DSR)
icount->dsr++;
if (delta & AMBA_UARTFR_CTS) {
icount->cts++;
if (info->flags & ASYNC_CTS_FLOW) {
status &= AMBA_UARTFR_CTS;
if (info->tty->hw_stopped) {
if (status) {
info->tty->hw_stopped = 0;
ambauart_enable_tx_interrupt(info);
ambauart_event(info, EVT_WRITE_WAKEUP);
}
} else {
if (!status) {
info->tty->hw_stopped = 1;
ambauart_disable_tx_interrupt(info);
}
}
}
}
wake_up_interruptible(&info->delta_msr_wait);
}
static void ambauart_int(int irq, void *dev_id, struct pt_regs *regs)
{
struct amba_info *info = dev_id;
unsigned int status, pass_counter = 0;
#if DEBUG_LEDS
// tell the world
set_leds(get_leds() | RED_LED);
#endif
status = UART_GET_INT_STATUS(info->port);
do {
/*
* FIXME: what about clearing the interrupts?
*/
if (status & (AMBA_UARTIIR_RTIS | AMBA_UARTIIR_RIS))
#ifdef SUPPORT_SYSRQ
ambauart_rx_chars(info, regs);
#else
ambauart_rx_chars(info);
#endif
if (status & AMBA_UARTIIR_TIS)
ambauart_tx_chars(info);
if (status & AMBA_UARTIIR_MIS)
ambauart_modem_status(info);
if (pass_counter++ > AMBA_ISR_PASS_LIMIT)
break;
status = UART_GET_INT_STATUS(info->port);
} while (status & (AMBA_UARTIIR_RTIS | AMBA_UARTIIR_RIS | AMBA_UARTIIR_TIS));
#if DEBUG_LEDS
// tell the world
set_leds(get_leds() & ~RED_LED);
#endif
}
static void ambauart_tasklet_action(unsigned long data)
{
struct amba_info *info = (struct amba_info *)data;
struct tty_struct *tty;
tty = info->tty;
if (!tty || !test_and_clear_bit(EVT_WRITE_WAKEUP, &info->event))
return;
if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
tty->ldisc.write_wakeup)
(tty->ldisc.write_wakeup)(tty);
wake_up_interruptible(&tty->write_wait);
}
static int ambauart_startup(struct amba_info *info)
{
unsigned long flags;
unsigned long page;
int retval = 0;
page = get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
save_flags(flags); cli();
if (info->flags & ASYNC_INITIALIZED) {
free_page(page);
goto errout;
}
if (info->xmit.buf)
free_page(page);
else
info->xmit.buf = (unsigned char *) page;
/*
* Allocate the IRQ
*/
retval = request_irq(info->port->irq, ambauart_int, 0, "amba", info);
if (retval) {
if (capable(CAP_SYS_ADMIN)) {
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
retval = 0;
}
goto errout;
}
info->mctrl = 0;
if (info->tty->termios->c_cflag & CBAUD)
info->mctrl = TIOCM_RTS | TIOCM_DTR;
info->port->set_mctrl(info->port, info->mctrl);
/*
* initialise the old status of the modem signals
*/
info->old_status = UART_GET_FR(info->port) & AMBA_UARTFR_MODEM_ANY;
/*
* Finally, enable interrupts
*/
ambauart_enable_rx_interrupt(info);
if (info->tty)
clear_bit(TTY_IO_ERROR, &info->tty->flags);
info->xmit.head = info->xmit.tail = 0;
/*
* Set up the tty->alt_speed kludge
*/
if (info->tty) {
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
info->tty->alt_speed = 57600;
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
info->tty->alt_speed = 115200;
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
info->tty->alt_speed = 230400;
if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
info->tty->alt_speed = 460800;
}
/*
* and set the speed of the serial port
*/
ambauart_change_speed(info, 0);
info->flags |= ASYNC_INITIALIZED;
restore_flags(flags);
return 0;
errout:
restore_flags(flags);
return retval;
}
/*
* This routine will shutdown a serial port; interrupts are disabled, and
* DTR is dropped if the hangup on close termio flag is on.
*/
static void ambauart_shutdown(struct amba_info *info)
{
unsigned long flags;
if (!(info->flags & ASYNC_INITIALIZED))
return;
save_flags(flags); cli(); /* Disable interrupts */
/*
* clear delta_msr_wait queue to avoid mem leaks: we may free the irq
* here so the queue might never be woken up
*/
wake_up_interruptible(&info->delta_msr_wait);
/*
* Free the IRQ
*/
free_irq(info->port->irq, info);
if (info->xmit.buf) {
unsigned long pg = (unsigned long) info->xmit.buf;
info->xmit.buf = NULL;
free_page(pg);
}
/*
* disable all interrupts, disable the port
*/
UART_PUT_CR(info->port, 0);
/* disable break condition and fifos */
UART_PUT_LCRH(info->port, UART_GET_LCRH(info->port) &
~(AMBA_UARTLCR_H_BRK | AMBA_UARTLCR_H_FEN));
if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
info->mctrl &= ~(TIOCM_DTR|TIOCM_RTS);
info->port->set_mctrl(info->port, info->mctrl);
/* kill off our tasklet */
tasklet_kill(&info->tlet);
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
info->flags &= ~ASYNC_INITIALIZED;
restore_flags(flags);
}
static void ambauart_change_speed(struct amba_info *info, struct termios *old_termios)
{
unsigned int lcr_h, baud, quot, cflag, old_cr, bits;
unsigned long flags;
if (!info->tty || !info->tty->termios)
return;
cflag = info->tty->termios->c_cflag;
#if DEBUG
printk("ambauart_set_cflag(0x%x) called\n", cflag);
#endif
/* byte size and parity */
switch (cflag & CSIZE) {
case CS5: lcr_h = AMBA_UARTLCR_H_WLEN_5; bits = 7; break;
case CS6: lcr_h = AMBA_UARTLCR_H_WLEN_6; bits = 8; break;
case CS7: lcr_h = AMBA_UARTLCR_H_WLEN_7; bits = 9; break;
default: lcr_h = AMBA_UARTLCR_H_WLEN_8; bits = 10; break; // CS8
}
if (cflag & CSTOPB) {
lcr_h |= AMBA_UARTLCR_H_STP2;
bits ++;
}
if (cflag & PARENB) {
lcr_h |= AMBA_UARTLCR_H_PEN;
bits++;
if (!(cflag & PARODD))
lcr_h |= AMBA_UARTLCR_H_EPS;
}
if (info->port->fifosize > 1)
lcr_h |= AMBA_UARTLCR_H_FEN;
do {
/* Determine divisor based on baud rate */
baud = tty_get_baud_rate(info->tty);
if (!baud)
baud = 9600;
if (baud == 38400 &&
((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
quot = info->state->custom_divisor;
else
quot = (info->port->uartclk / (16 * baud)) - 1;
if (!quot && old_termios) {
info->tty->termios->c_cflag &= ~CBAUD;
info->tty->termios->c_cflag |= (old_termios->c_cflag & CBAUD);
old_termios = NULL;
}
} while (quot == 0 && old_termios);
/* As a last resort, if the quotient is zero, default to 9600 bps */
if (!quot)
quot = (info->port->uartclk / (16 * 9600)) - 1;
info->timeout = (info->port->fifosize * HZ * bits * quot) /
(info->port->uartclk / 16);
info->timeout += HZ/50; /* Add .02 seconds of slop */
if (cflag & CRTSCTS)
info->flags |= ASYNC_CTS_FLOW;
else
info->flags &= ~ASYNC_CTS_FLOW;
if (cflag & CLOCAL)
info->flags &= ~ASYNC_CHECK_CD;
else
info->flags |= ASYNC_CHECK_CD;
/*
* Set up parity check flag
*/
#define RELEVENT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
info->read_status_mask = AMBA_UARTRSR_OE;
if (I_INPCK(info->tty))
info->read_status_mask |= AMBA_UARTRSR_FE | AMBA_UARTRSR_PE;
if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
info->read_status_mask |= AMBA_UARTRSR_BE;
/*
* Characters to ignore
*/
info->ignore_status_mask = 0;
if (I_IGNPAR(info->tty))
info->ignore_status_mask |= AMBA_UARTRSR_FE | AMBA_UARTRSR_PE;
if (I_IGNBRK(info->tty)) {
info->ignore_status_mask |= AMBA_UARTRSR_BE;
/*
* If we're ignoring parity and break indicators,
* ignore overruns to (for real raw support).
*/
if (I_IGNPAR(info->tty))
info->ignore_status_mask |= AMBA_UARTRSR_OE;
}
/* first, disable everything */
save_flags(flags); cli();
old_cr = UART_GET_CR(info->port) &= ~AMBA_UARTCR_MSIE;
if ((info->flags & ASYNC_HARDPPS_CD) ||
(cflag & CRTSCTS) ||
!(cflag & CLOCAL))
old_cr |= AMBA_UARTCR_MSIE;
UART_PUT_CR(info->port, 0);
restore_flags(flags);
/* Set baud rate */
UART_PUT_LCRM(info->port, ((quot & 0xf00) >> 8));
UART_PUT_LCRL(info->port, (quot & 0xff));
/*
* ----------v----------v----------v----------v-----
* NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
* ----------^----------^----------^----------^-----
*/
UART_PUT_LCRH(info->port, lcr_h);
UART_PUT_CR(info->port, old_cr);
}
static void ambauart_put_char(struct tty_struct *tty, u_char ch)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
if (!tty || !info->xmit.buf)
return;
save_flags(flags); cli();
if (CIRC_SPACE(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE) != 0) {
info->xmit.buf[info->xmit.head] = ch;
info->xmit.head = (info->xmit.head + 1) & (AMBA_XMIT_SIZE - 1);
}
restore_flags(flags);
}
static void ambauart_flush_chars(struct tty_struct *tty)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
if (info->xmit.head == info->xmit.tail
|| tty->stopped
|| tty->hw_stopped
|| !info->xmit.buf)
return;
save_flags(flags); cli();
ambauart_enable_tx_interrupt(info);
restore_flags(flags);
}
static int ambauart_write(struct tty_struct *tty, int from_user,
const u_char * buf, int count)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
int c, ret = 0;
if (!tty || !info->xmit.buf || !tmp_buf)
return 0;
save_flags(flags);
if (from_user) {
down(&tmp_buf_sem);
while (1) {
int c1;
c = CIRC_SPACE_TO_END(info->xmit.head,
info->xmit.tail,
AMBA_XMIT_SIZE);
if (count < c)
c = count;
if (c <= 0)
break;
c -= copy_from_user(tmp_buf, buf, c);
if (!c) {
if (!ret)
ret = -EFAULT;
break;
}
cli();
c1 = CIRC_SPACE_TO_END(info->xmit.head,
info->xmit.tail,
AMBA_XMIT_SIZE);
if (c1 < c)
c = c1;
memcpy(info->xmit.buf + info->xmit.head, tmp_buf, c);
info->xmit.head = (info->xmit.head + c) &
(AMBA_XMIT_SIZE - 1);
restore_flags(flags);
buf += c;
count -= c;
ret += c;
}
up(&tmp_buf_sem);
} else {
cli();
while (1) {
c = CIRC_SPACE_TO_END(info->xmit.head,
info->xmit.tail,
AMBA_XMIT_SIZE);
if (count < c)
c = count;
if (c <= 0)
break;
memcpy(info->xmit.buf + info->xmit.head, buf, c);
info->xmit.head = (info->xmit.head + c) &
(AMBA_XMIT_SIZE - 1);
buf += c;
count -= c;
ret += c;
}
restore_flags(flags);
}
if (info->xmit.head != info->xmit.tail
&& !tty->stopped
&& !tty->hw_stopped)
ambauart_enable_tx_interrupt(info);
return ret;
}
static int ambauart_write_room(struct tty_struct *tty)
{
struct amba_info *info = tty->driver_data;
return CIRC_SPACE(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE);
}
static int ambauart_chars_in_buffer(struct tty_struct *tty)
{
struct amba_info *info = tty->driver_data;
return CIRC_CNT(info->xmit.head, info->xmit.tail, AMBA_XMIT_SIZE);
}
static void ambauart_flush_buffer(struct tty_struct *tty)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
#if DEBUG
printk("ambauart_flush_buffer(%d) called\n",
MINOR(tty->device) - tty->driver.minor_start);
#endif
save_flags(flags); cli();
info->xmit.head = info->xmit.tail = 0;
restore_flags(flags);
wake_up_interruptible(&tty->write_wait);
if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
tty->ldisc.write_wakeup)
(tty->ldisc.write_wakeup)(tty);
}
/*
* This function is used to send a high-priority XON/XOFF character to
* the device
*/
static void ambauart_send_xchar(struct tty_struct *tty, char ch)
{
struct amba_info *info = tty->driver_data;
info->x_char = ch;
if (ch)
ambauart_enable_tx_interrupt(info);
}
static void ambauart_throttle(struct tty_struct *tty)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
if (I_IXOFF(tty))
ambauart_send_xchar(tty, STOP_CHAR(tty));
if (tty->termios->c_cflag & CRTSCTS) {
save_flags(flags); cli();
info->mctrl &= ~TIOCM_RTS;
info->port->set_mctrl(info->port, info->mctrl);
restore_flags(flags);
}
}
static void ambauart_unthrottle(struct tty_struct *tty)
{
struct amba_info *info = (struct amba_info *) tty->driver_data;
unsigned long flags;
if (I_IXOFF(tty)) {
if (info->x_char)
info->x_char = 0;
else
ambauart_send_xchar(tty, START_CHAR(tty));
}
if (tty->termios->c_cflag & CRTSCTS) {
save_flags(flags); cli();
info->mctrl |= TIOCM_RTS;
info->port->set_mctrl(info->port, info->mctrl);
restore_flags(flags);
}
}
static int get_serial_info(struct amba_info *info, struct serial_struct *retinfo)
{
struct amba_state *state = info->state;
struct amba_port *port = info->port;
struct serial_struct tmp;
memset(&tmp, 0, sizeof(tmp));
tmp.type = 0;
tmp.line = state->line;
tmp.port = port->uart_base;
if (HIGH_BITS_OFFSET)
tmp.port_high = port->uart_base >> HIGH_BITS_OFFSET;
tmp.irq = port->irq;
tmp.flags = 0;
tmp.xmit_fifo_size = port->fifosize;
tmp.baud_base = port->uartclk / 16;
tmp.close_delay = state->close_delay;
tmp.closing_wait = state->closing_wait;
tmp.custom_divisor = state->custom_divisor;
if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
return -EFAULT;
return 0;
}
static int set_serial_info(struct amba_info *info,
struct serial_struct *newinfo)
{
struct serial_struct new_serial;
struct amba_state *state, old_state;
struct amba_port *port;
unsigned long new_port;
unsigned int i, change_irq, change_port;
int retval = 0;
if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
return -EFAULT;
state = info->state;
old_state = *state;
port = info->port;
new_port = new_serial.port;
if (HIGH_BITS_OFFSET)
new_port += (unsigned long) new_serial.port_high << HIGH_BITS_OFFSET;
change_irq = new_serial.irq != port->irq;
change_port = new_port != port->uart_base;
if (!capable(CAP_SYS_ADMIN)) {
if (change_irq || change_port ||
(new_serial.baud_base != port->uartclk / 16) ||
(new_serial.close_delay != state->close_delay) ||
(new_serial.xmit_fifo_size != port->fifosize) ||
((new_serial.flags & ~ASYNC_USR_MASK) !=
(state->flags & ~ASYNC_USR_MASK)))
return -EPERM;
state->flags = ((state->flags & ~ASYNC_USR_MASK) |
(new_serial.flags & ASYNC_USR_MASK));
info->flags = ((info->flags & ~ASYNC_USR_MASK) |
(new_serial.flags & ASYNC_USR_MASK));
state->custom_divisor = new_serial.custom_divisor;
goto check_and_exit;
}
if ((new_serial.irq >= NR_IRQS) || (new_serial.irq < 0) ||
(new_serial.baud_base < 9600))
return -EINVAL;
if (new_serial.type && change_port) {
for (i = 0; i < SERIAL_AMBA_NR; i++)
if ((port != amba_ports + i) &&
amba_ports[i].uart_base != new_port)
return -EADDRINUSE;
}
if ((change_port || change_irq) && (state->count > 1))
return -EBUSY;
/*
* OK, past this point, all the error checking has been done.
* At this point, we start making changes.....
*/
port->uartclk = new_serial.baud_base * 16;
state->flags = ((state->flags & ~ASYNC_FLAGS) |
(new_serial.flags & ASYNC_FLAGS));
info->flags = ((state->flags & ~ASYNC_INTERNAL_FLAGS) |
(info->flags & ASYNC_INTERNAL_FLAGS));
state->custom_divisor = new_serial.custom_divisor;
state->close_delay = new_serial.close_delay * HZ / 100;
state->closing_wait = new_serial.closing_wait * HZ / 100;
info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
port->fifosize = new_serial.xmit_fifo_size;
if (change_port || change_irq) {
/*
* We need to shutdown the serial port at the old
* port/irq combination.
*/
ambauart_shutdown(info);
port->irq = new_serial.irq;
port->uart_base = new_port;
}
check_and_exit:
if (!port->uart_base)
return 0;
if (info->flags & ASYNC_INITIALIZED) {
if ((old_state.flags & ASYNC_SPD_MASK) !=
(state->flags & ASYNC_SPD_MASK) ||
(old_state.custom_divisor != state->custom_divisor)) {
if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
info->tty->alt_speed = 57600;
if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
info->tty->alt_speed = 115200;
if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
info->tty->alt_speed = 230400;
if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
info->tty->alt_speed = 460800;
ambauart_change_speed(info, NULL);
}
} else
retval = ambauart_startup(info);
return retval;
}
/*
* get_lsr_info - get line status register info
*/
static int get_lsr_info(struct amba_info *info, unsigned int *value)
{
unsigned int result, status;
unsigned long flags;
save_flags(flags); cli();
status = UART_GET_FR(info->port);
restore_flags(flags);
result = status & AMBA_UARTFR_BUSY ? TIOCSER_TEMT : 0;
/*
* If we're about to load something into the transmit
* register, we'll pretend the transmitter isn't empty to
* avoid a race condition (depending on when the transmit
* interrupt happens).
*/
if (info->x_char ||
((CIRC_CNT(info->xmit.head, info->xmit.tail,
AMBA_XMIT_SIZE) > 0) &&
!info->tty->stopped && !info->tty->hw_stopped))
result &= TIOCSER_TEMT;
return put_user(result, value);
}
static int get_modem_info(struct amba_info *info, unsigned int *value)
{
unsigned int result = info->mctrl;
unsigned int status;
status = UART_GET_FR(info->port);
if (status & AMBA_UARTFR_DCD)
result |= TIOCM_CAR;
if (status & AMBA_UARTFR_DSR)
result |= TIOCM_DSR;
if (status & AMBA_UARTFR_CTS)
result |= TIOCM_CTS;
return put_user(result, value);
}
static int set_modem_info(struct amba_info *info, unsigned int cmd,
unsigned int *value)
{
unsigned int arg, old;
unsigned long flags;
if (get_user(arg, value))
return -EFAULT;
old = info->mctrl;
switch (cmd) {
case TIOCMBIS:
info->mctrl |= arg;
break;
case TIOCMBIC:
info->mctrl &= ~arg;
break;
case TIOCMSET:
info->mctrl = arg;
break;
default:
return -EINVAL;
}
save_flags(flags); cli();
if (old != info->mctrl)
info->port->set_mctrl(info->port, info->mctrl);
restore_flags(flags);
return 0;
}
static void ambauart_break_ctl(struct tty_struct *tty, int break_state)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
unsigned int lcr_h;
save_flags(flags); cli();
lcr_h = UART_GET_LCRH(info->port);
if (break_state == -1)
lcr_h |= AMBA_UARTLCR_H_BRK;
else
lcr_h &= ~AMBA_UARTLCR_H_BRK;
UART_PUT_LCRH(info->port, lcr_h);
restore_flags(flags);
}
static int ambauart_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
struct amba_info *info = tty->driver_data;
struct amba_icount cprev, cnow;
struct serial_icounter_struct icount;
unsigned long flags;
if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
(cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
(cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
if (tty->flags & (1 << TTY_IO_ERROR))
return -EIO;
}
switch (cmd) {
case TIOCMGET:
return get_modem_info(info, (unsigned int *)arg);
case TIOCMBIS:
case TIOCMBIC:
case TIOCMSET:
return set_modem_info(info, cmd, (unsigned int *)arg);
case TIOCGSERIAL:
return get_serial_info(info,
(struct serial_struct *)arg);
case TIOCSSERIAL:
return set_serial_info(info,
(struct serial_struct *)arg);
case TIOCSERGETLSR: /* Get line status register */
return get_lsr_info(info, (unsigned int *)arg);
/*
* Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
* - mask passed in arg for lines of interest
* (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
* Caller should use TIOCGICOUNT to see which one it was
*/
case TIOCMIWAIT:
save_flags(flags); cli();
/* note the counters on entry */
cprev = info->state->icount;
/* Force modem status interrupts on */
UART_PUT_CR(info->port, UART_GET_CR(info->port) | AMBA_UARTCR_MSIE);
restore_flags(flags);
while (1) {
interruptible_sleep_on(&info->delta_msr_wait);
/* see if a signal did it */
if (signal_pending(current))
return -ERESTARTSYS;
save_flags(flags); cli();
cnow = info->state->icount; /* atomic copy */
restore_flags(flags);
if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
return -EIO; /* no change => error */
if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
return 0;
}
cprev = cnow;
}
/* NOTREACHED */
/*
* Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
* Return: write counters to the user passed counter struct
* NB: both 1->0 and 0->1 transitions are counted except for
* RI where only 0->1 is counted.
*/
case TIOCGICOUNT:
save_flags(flags); cli();
cnow = info->state->icount;
restore_flags(flags);
icount.cts = cnow.cts;
icount.dsr = cnow.dsr;
icount.rng = cnow.rng;
icount.dcd = cnow.dcd;
icount.rx = cnow.rx;
icount.tx = cnow.tx;
icount.frame = cnow.frame;
icount.overrun = cnow.overrun;
icount.parity = cnow.parity;
icount.brk = cnow.brk;
icount.buf_overrun = cnow.buf_overrun;
return copy_to_user((void *)arg, &icount, sizeof(icount))
? -EFAULT : 0;
default:
return -ENOIOCTLCMD;
}
return 0;
}
static void ambauart_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
struct amba_info *info = tty->driver_data;
unsigned long flags;
unsigned int cflag = tty->termios->c_cflag;
if ((cflag ^ old_termios->c_cflag) == 0 &&
RELEVENT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0)
return;
ambauart_change_speed(info, old_termios);
/* Handle transition to B0 status */
if ((old_termios->c_cflag & CBAUD) &&
!(cflag & CBAUD)) {
save_flags(flags); cli();
info->mctrl &= ~(TIOCM_RTS | TIOCM_DTR);
info->port->set_mctrl(info->port, info->mctrl);
restore_flags(flags);
}
/* Handle transition away from B0 status */
if (!(old_termios->c_cflag & CBAUD) &&
(cflag & CBAUD)) {
save_flags(flags); cli();
info->mctrl |= TIOCM_DTR;
if (!(cflag & CRTSCTS) ||
!test_bit(TTY_THROTTLED, &tty->flags))
info->mctrl |= TIOCM_RTS;
info->port->set_mctrl(info->port, info->mctrl);
restore_flags(flags);
}
/* Handle turning off CRTSCTS */
if ((old_termios->c_cflag & CRTSCTS) &&
!(cflag & CRTSCTS)) {
tty->hw_stopped = 0;
ambauart_start(tty);
}
#if 0
/*
* No need to wake up processes in open wait, since they
* sample the CLOCAL flag once, and don't recheck it.
* XXX It's not clear whether the current behavior is correct
* or not. Hence, this may change.....
*/
if (!(old_termios->c_cflag & CLOCAL) &&
(tty->termios->c_cflag & CLOCAL))
wake_up_interruptible(&info->open_wait);
#endif
}
static void ambauart_close(struct tty_struct *tty, struct file *filp)
{
struct amba_info *info = tty->driver_data;
struct amba_state *state;
unsigned long flags;
if (!info)
return;
state = info->state;
#if DEBUG
printk("ambauart_close() called\n");
#endif
save_flags(flags); cli();
if (tty_hung_up_p(filp)) {
MOD_DEC_USE_COUNT;
restore_flags(flags);
return;
}
if ((tty->count == 1) && (state->count != 1)) {
/*
* Uh, oh. tty->count is 1, which means that the tty
* structure will be freed. state->count should always
* be one in these conditions. If it's greater than
* one, we've got real problems, since it means the
* serial port won't be shutdown.
*/
printk("ambauart_close: bad serial port count; tty->count is 1, "
"state->count is %d\n", state->count);
state->count = 1;
}
if (--state->count < 0) {
printk("rs_close: bad serial port count for %s%d: %d\n",
tty->driver.name, info->state->line, state->count);
state->count = 0;
}
if (state->count) {
MOD_DEC_USE_COUNT;
restore_flags(flags);
return;
}
info->flags |= ASYNC_CLOSING;
restore_flags(flags);
/*
* Save the termios structure, since this port may have
* separate termios for callout and dialin.
*/
if (info->flags & ASYNC_NORMAL_ACTIVE)
info->state->normal_termios = *tty->termios;
if (info->flags & ASYNC_CALLOUT_ACTIVE)
info->state->callout_termios = *tty->termios;
/*
* Now we wait for the transmit buffer to clear; and we notify
* the line discipline to only process XON/XOFF characters.
*/
tty->closing = 1;
if (info->state->closing_wait != ASYNC_CLOSING_WAIT_NONE)
tty_wait_until_sent(tty, info->state->closing_wait);
/*
* At this point, we stop accepting input. To do this, we
* disable the receive line status interrupts.
*/
if (info->flags & ASYNC_INITIALIZED) {
ambauart_disable_rx_interrupt(info);
/*
* Before we drop DTR, make sure the UART transmitter
* has completely drained; this is especially
* important if there is a transmit FIFO!
*/
ambauart_wait_until_sent(tty, info->timeout);
}
ambauart_shutdown(info);
if (tty->driver.flush_buffer)
tty->driver.flush_buffer(tty);
if (tty->ldisc.flush_buffer)
tty->ldisc.flush_buffer(tty);
tty->closing = 0;
info->event = 0;
info->tty = NULL;
if (info->blocked_open) {
if (info->state->close_delay) {
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(info->state->close_delay);
}
wake_up_interruptible(&info->open_wait);
}
info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
ASYNC_CLOSING);
wake_up_interruptible(&info->close_wait);
MOD_DEC_USE_COUNT;
}
static void ambauart_wait_until_sent(struct tty_struct *tty, int timeout)
{
struct amba_info *info = (struct amba_info *) tty->driver_data;
unsigned long char_time, expire;
unsigned int status;
if (info->port->fifosize == 0)
return;
/*
* Set the check interval to be 1/5 of the estimated time to
* send a single character, and make it at least 1. The check
* interval should also be less than the timeout.
*
* Note: we have to use pretty tight timings here to satisfy
* the NIST-PCTS.
*/
char_time = (info->timeout - HZ/50) / info->port->fifosize;
char_time = char_time / 5;
if (char_time == 0)
char_time = 1;
if (timeout && timeout < char_time)
char_time = timeout;
/*
* If the transmitter hasn't cleared in twice the approximate
* amount of time to send the entire FIFO, it probably won't
* ever clear. This assumes the UART isn't doing flow
* control, which is currently the case. Hence, if it ever
* takes longer than info->timeout, this is probably due to a
* UART bug of some kind. So, we clamp the timeout parameter at
* 2*info->timeout.
*/
if (!timeout || timeout > 2 * info->timeout)
timeout = 2 * info->timeout;
expire = jiffies + timeout;
#if DEBUG
printk("ambauart_wait_until_sent(%d), jiff=%lu, expire=%lu...\n",
MINOR(tty->device) - tty->driver.minor_start, jiffies,
expire);
#endif
while (UART_GET_FR(info->port) & AMBA_UARTFR_BUSY) {
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(char_time);
if (signal_pending(current))
break;
if (timeout && time_after(jiffies, expire))
break;
status = UART_GET_FR(info->port);
}
set_current_state(TASK_RUNNING);
}
static void ambauart_hangup(struct tty_struct *tty)
{
struct amba_info *info = tty->driver_data;
struct amba_state *state = info->state;
ambauart_flush_buffer(tty);
if (info->flags & ASYNC_CLOSING)
return;
ambauart_shutdown(info);
info->event = 0;
state->count = 0;
info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
info->tty = NULL;
wake_up_interruptible(&info->open_wait);
}
static int block_til_ready(struct tty_struct *tty, struct file *filp,
struct amba_info *info)
{
DECLARE_WAITQUEUE(wait, current);
struct amba_state *state = info->state;
unsigned long flags;
int do_clocal = 0, extra_count = 0, retval;
/*
* If the device is in the middle of being closed, then block
* until it's done, and then try again.
*/
if (tty_hung_up_p(filp) ||
(info->flags & ASYNC_CLOSING)) {
if (info->flags & ASYNC_CLOSING)
interruptible_sleep_on(&info->close_wait);
return (info->flags & ASYNC_HUP_NOTIFY) ?
-EAGAIN : -ERESTARTSYS;
}
/*
* If this is a callout device, then just make sure the normal
* device isn't being used.
*/
if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
if (info->flags & ASYNC_NORMAL_ACTIVE)
return -EBUSY;
if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
(info->flags & ASYNC_SESSION_LOCKOUT) &&
(info->session != current->session))
return -EBUSY;
if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
(info->flags & ASYNC_PGRP_LOCKOUT) &&
(info->pgrp != current->pgrp))
return -EBUSY;
info->flags |= ASYNC_CALLOUT_ACTIVE;
return 0;
}
/*
* If non-blocking mode is set, or the port is not enabled,
* then make the check up front and then exit.
*/
if ((filp->f_flags & O_NONBLOCK) ||
(tty->flags & (1 << TTY_IO_ERROR))) {
if (info->flags & ASYNC_CALLOUT_ACTIVE)
return -EBUSY;
info->flags |= ASYNC_NORMAL_ACTIVE;
return 0;
}
if (info->flags & ASYNC_CALLOUT_ACTIVE) {
if (state->normal_termios.c_cflag & CLOCAL)
do_clocal = 1;
} else {
if (tty->termios->c_cflag & CLOCAL)
do_clocal = 1;
}
/*
* Block waiting for the carrier detect and the line to become
* free (i.e., not in use by the callout). While we are in
* this loop, state->count is dropped by one, so that
* rs_close() knows when to free things. We restore it upon
* exit, either normal or abnormal.
*/
retval = 0;
add_wait_queue(&info->open_wait, &wait);
save_flags(flags); cli();
if (!tty_hung_up_p(filp)) {
extra_count = 1;
state->count--;
}
restore_flags(flags);
info->blocked_open++;
while (1) {
save_flags(flags); cli();
if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
(tty->termios->c_cflag & CBAUD)) {
info->mctrl = TIOCM_DTR | TIOCM_RTS;
info->port->set_mctrl(info->port, info->mctrl);
}
restore_flags(flags);
set_current_state(TASK_INTERRUPTIBLE);
if (tty_hung_up_p(filp) ||
!(info->flags & ASYNC_INITIALIZED)) {
if (info->flags & ASYNC_HUP_NOTIFY)
retval = -EAGAIN;
else
retval = -ERESTARTSYS;
break;
}
if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
!(info->flags & ASYNC_CLOSING) &&
(do_clocal || (UART_GET_FR(info->port) & AMBA_UARTFR_DCD)))
break;
if (signal_pending(current)) {
retval = -ERESTARTSYS;
break;
}
schedule();
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&info->open_wait, &wait);
if (extra_count)
state->count++;
info->blocked_open--;
if (retval)
return retval;
info->flags |= ASYNC_NORMAL_ACTIVE;
return 0;
}
static struct amba_info *ambauart_get(int line)
{
struct amba_info *info;
struct amba_state *state = amba_state + line;
state->count++;
if (state->info)
return state->info;
info = kmalloc(sizeof(struct amba_info), GFP_KERNEL);
if (info) {
memset(info, 0, sizeof(struct amba_info));
init_waitqueue_head(&info->open_wait);
init_waitqueue_head(&info->close_wait);
init_waitqueue_head(&info->delta_msr_wait);
info->flags = state->flags;
info->state = state;
info->port = amba_ports + line;
tasklet_init(&info->tlet, ambauart_tasklet_action,
(unsigned long)info);
}
if (state->info) {
kfree(info);
return state->info;
}
state->info = info;
return info;
}
static int ambauart_open(struct tty_struct *tty, struct file *filp)
{
struct amba_info *info;
int retval, line = MINOR(tty->device) - tty->driver.minor_start;
#if DEBUG
printk("ambauart_open(%d) called\n", line);
#endif
// is this a line that we've got?
MOD_INC_USE_COUNT;
if (line >= SERIAL_AMBA_NR) {
MOD_DEC_USE_COUNT;
return -ENODEV;
}
info = ambauart_get(line);
if (!info)
return -ENOMEM;
tty->driver_data = info;
info->tty = tty;
info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
/*
* Make sure we have the temporary buffer allocated
*/
if (!tmp_buf) {
unsigned long page = get_zeroed_page(GFP_KERNEL);
if (tmp_buf)
free_page(page);
else if (!page) {
MOD_DEC_USE_COUNT;
return -ENOMEM;
}
tmp_buf = (u_char *)page;
}
/*
* If the port is in the middle of closing, bail out now.
*/
if (tty_hung_up_p(filp) ||
(info->flags & ASYNC_CLOSING)) {
if (info->flags & ASYNC_CLOSING)
interruptible_sleep_on(&info->close_wait);
MOD_DEC_USE_COUNT;
return -EAGAIN;
}
/*
* Start up the serial port
*/
retval = ambauart_startup(info);
if (retval) {
MOD_DEC_USE_COUNT;
return retval;
}
retval = block_til_ready(tty, filp, info);
if (retval) {
MOD_DEC_USE_COUNT;
return retval;
}
if ((info->state->count == 1) &&
(info->flags & ASYNC_SPLIT_TERMIOS)) {
if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
*tty->termios = info->state->normal_termios;
else
*tty->termios = info->state->callout_termios;
}
#ifdef CONFIG_SERIAL_AMBA_CONSOLE
if (ambauart_cons.cflag && ambauart_cons.index == line) {
tty->termios->c_cflag = ambauart_cons.cflag;
ambauart_cons.cflag = 0;
}
#endif
ambauart_change_speed(info, NULL);
info->session = current->session;
info->pgrp = current->pgrp;
return 0;
}
int __init ambauart_init(void)
{
int i;
ambanormal_driver.magic = TTY_DRIVER_MAGIC;
ambanormal_driver.driver_name = "serial_amba";
ambanormal_driver.name = SERIAL_AMBA_NAME;
ambanormal_driver.major = SERIAL_AMBA_MAJOR;
ambanormal_driver.minor_start = SERIAL_AMBA_MINOR;
ambanormal_driver.num = SERIAL_AMBA_NR;
ambanormal_driver.type = TTY_DRIVER_TYPE_SERIAL;
ambanormal_driver.subtype = SERIAL_TYPE_NORMAL;
ambanormal_driver.init_termios = tty_std_termios;
ambanormal_driver.init_termios.c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
ambanormal_driver.flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS;
ambanormal_driver.refcount = &ambauart_refcount;
ambanormal_driver.table = ambauart_table;
ambanormal_driver.termios = ambauart_termios;
ambanormal_driver.termios_locked = ambauart_termios_locked;
ambanormal_driver.open = ambauart_open;
ambanormal_driver.close = ambauart_close;
ambanormal_driver.write = ambauart_write;
ambanormal_driver.put_char = ambauart_put_char;
ambanormal_driver.flush_chars = ambauart_flush_chars;
ambanormal_driver.write_room = ambauart_write_room;
ambanormal_driver.chars_in_buffer = ambauart_chars_in_buffer;
ambanormal_driver.flush_buffer = ambauart_flush_buffer;
ambanormal_driver.ioctl = ambauart_ioctl;
ambanormal_driver.throttle = ambauart_throttle;
ambanormal_driver.unthrottle = ambauart_unthrottle;
ambanormal_driver.send_xchar = ambauart_send_xchar;
ambanormal_driver.set_termios = ambauart_set_termios;
ambanormal_driver.stop = ambauart_stop;
ambanormal_driver.start = ambauart_start;
ambanormal_driver.hangup = ambauart_hangup;
ambanormal_driver.break_ctl = ambauart_break_ctl;
ambanormal_driver.wait_until_sent = ambauart_wait_until_sent;
ambanormal_driver.read_proc = NULL;
/*
* The callout device is just like the normal device except for
* the major number and the subtype code.
*/
ambacallout_driver = ambanormal_driver;
ambacallout_driver.name = CALLOUT_AMBA_NAME;
ambacallout_driver.major = CALLOUT_AMBA_MAJOR;
ambacallout_driver.subtype = SERIAL_TYPE_CALLOUT;
ambacallout_driver.read_proc = NULL;
ambacallout_driver.proc_entry = NULL;
if (tty_register_driver(&ambanormal_driver))
panic("Couldn't register AMBA serial driver\n");
if (tty_register_driver(&ambacallout_driver))
panic("Couldn't register AMBA callout driver\n");
for (i = 0; i < SERIAL_AMBA_NR; i++) {
struct amba_state *state = amba_state + i;
state->line = i;
state->close_delay = 5 * HZ / 10;
state->closing_wait = 30 * HZ;
state->callout_termios = ambacallout_driver.init_termios;
state->normal_termios = ambanormal_driver.init_termios;
}
return 0;
}
__initcall(ambauart_init);
#ifdef CONFIG_SERIAL_AMBA_CONSOLE
/************** console driver *****************/
/*
* This code is currently never used; console->read is never called.
* Therefore, although we have an implementation, we don't use it.
* FIXME: the "const char *s" should be fixed to "char *s" some day.
* (when the definition in include/linux/console.h is also fixed)
*/
#ifdef used_and_not_const_char_pointer
static int ambauart_console_read(struct console *co, const char *s, u_int count)
{
struct amba_port *port = &amba_ports[co->index];
unsigned int status;
char *w;
int c;
#if DEBUG
printk("ambauart_console_read() called\n");
#endif
c = 0;
w = s;
while (c < count) {
status = UART_GET_FR(port);
if (UART_RX_DATA(status)) {
*w++ = UART_GET_CHAR(port);
c++;
} else {
// nothing more to get, return
return c;
}
}
// return the count
return c;
}
#endif
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*
* The console must be locked when we get here.
*/
static void ambauart_console_write(struct console *co, const char *s, u_int count)
{
struct amba_port *port = &amba_ports[co->index];
unsigned int status, old_cr;
int i;
/*
* First save the CR then disable the interrupts
*/
old_cr = UART_GET_CR(port);
UART_PUT_CR(port, AMBA_UARTCR_UARTEN);
/*
* Now, do each character
*/
for (i = 0; i < count; i++) {
do {
status = UART_GET_FR(port);
} while (!UART_TX_READY(status));
UART_PUT_CHAR(port, s[i]);
if (s[i] == '\n') {
do {
status = UART_GET_FR(port);
} while (!UART_TX_READY(status));
UART_PUT_CHAR(port, '\r');
}
}
/*
* Finally, wait for transmitter to become empty
* and restore the TCR
*/
do {
status = UART_GET_FR(port);
} while (status & AMBA_UARTFR_BUSY);
UART_PUT_CR(port, old_cr);
}
/*
* Receive character from the serial port
*/
static int ambauart_console_wait_key(struct console *co)
{
struct amba_port *port = &amba_ports[co->index];
unsigned int status;
int c;
do {
status = UART_GET_FR(port);
} while (!UART_RX_DATA(status));
c = UART_GET_CHAR(port);
return c;
}
static kdev_t ambauart_console_device(struct console *c)
{
return MKDEV(SERIAL_AMBA_MAJOR, SERIAL_AMBA_MINOR + c->index);
}
static int __init ambauart_console_setup(struct console *co, char *options)
{
struct amba_port *port;
int baud = 38400;
int bits = 8;
int parity = 'n';
u_int cflag = CREAD | HUPCL | CLOCAL;
u_int lcr_h, quot;
if (co->index >= SERIAL_AMBA_NR)
co->index = 0;
port = &amba_ports[co->index];
if (options) {
char *s = options;
baud = simple_strtoul(s, NULL, 10);
while (*s >= '0' && *s <= '9')
s++;
if (*s) parity = *s++;
if (*s) bits = *s - '0';
}
/*
* Now construct a cflag setting.
*/
switch (baud) {
case 1200: cflag |= B1200; break;
case 2400: cflag |= B2400; break;
case 4800: cflag |= B4800; break;
default: cflag |= B9600; baud = 9600; break;
case 19200: cflag |= B19200; break;
case 38400: cflag |= B38400; break;
case 57600: cflag |= B57600; break;
case 115200: cflag |= B115200; break;
}
switch (bits) {
case 7: cflag |= CS7; lcr_h = AMBA_UARTLCR_H_WLEN_7; break;
default: cflag |= CS8; lcr_h = AMBA_UARTLCR_H_WLEN_8; break;
}
switch (parity) {
case 'o':
case 'O': cflag |= PARODD; lcr_h |= AMBA_UARTLCR_H_PEN; break;
case 'e':
case 'E': cflag |= PARENB; lcr_h |= AMBA_UARTLCR_H_PEN |
AMBA_UARTLCR_H_EPS; break;
}
co->cflag = cflag;
if (port->fifosize > 1)
lcr_h |= AMBA_UARTLCR_H_FEN;
quot = (port->uartclk / (16 * baud)) - 1;
UART_PUT_LCRL(port, (quot & 0xff));
UART_PUT_LCRM(port, (quot >> 8));
UART_PUT_LCRH(port, lcr_h);
/* we will enable the port as we need it */
UART_PUT_CR(port, 0);
return 0;
}
static struct console ambauart_cons =
{
name: SERIAL_AMBA_NAME,
write: ambauart_console_write,
#ifdef used_and_not_const_char_pointer
read: ambauart_console_read,
#endif
device: ambauart_console_device,
wait_key: ambauart_console_wait_key,
setup: ambauart_console_setup,
flags: CON_PRINTBUFFER,
index: -1,
};
void __init ambauart_console_init(void)
{
register_console(&ambauart_cons);
}
#endif /* CONFIG_SERIAL_AMBA_CONSOLE */
MODULE_LICENSE("GPL");
EXPORT_NO_SYMBOLS;
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