patch-2.4.0-test9 linux/drivers/char/serial_amba.c
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- Lines: 2031
- Date:
Mon Sep 18 15:15:22 2000
- Orig file:
v2.4.0-test8/linux/drivers/char/serial_amba.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.4.0-test8/linux/drivers/char/serial_amba.c linux/drivers/char/serial_amba.c
@@ -0,0 +1,2030 @@
+/*
+ * 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/malloc.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_lock must be held 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,
+ unblank: NULL,
+ setup: ambauart_console_setup,
+ flags: CON_PRINTBUFFER,
+ index: -1,
+};
+
+void __init ambauart_console_init(void)
+{
+ register_console(&ambauart_cons);
+}
+
+#endif /* CONFIG_SERIAL_AMBA_CONSOLE */
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)