Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/drivers/tc/zs.c b/drivers/tc/zs.c
new file mode 100644
index 0000000..4382ee6
--- /dev/null
+++ b/drivers/tc/zs.c
@@ -0,0 +1,2253 @@
+/*
+ * decserial.c: Serial port driver for IOASIC DECstations.
+ *
+ * Derived from drivers/sbus/char/sunserial.c by Paul Mackerras.
+ * Derived from drivers/macintosh/macserial.c by Harald Koerfgen.
+ *
+ * DECstation changes
+ * Copyright (C) 1998-2000 Harald Koerfgen
+ * Copyright (C) 2000, 2001, 2002, 2003, 2004 Maciej W. Rozycki
+ *
+ * For the rest of the code the original Copyright applies:
+ * Copyright (C) 1996 Paul Mackerras (Paul.Mackerras@cs.anu.edu.au)
+ * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
+ *
+ *
+ * Note: for IOASIC systems the wiring is as follows:
+ *
+ * mouse/keyboard:
+ * DIN-7 MJ-4 signal SCC
+ * 2 1 TxD <- A.TxD
+ * 3 4 RxD -> A.RxD
+ *
+ * EIA-232/EIA-423:
+ * DB-25 MMJ-6 signal SCC
+ * 2 2 TxD <- B.TxD
+ * 3 5 RxD -> B.RxD
+ * 4 RTS <- ~A.RTS
+ * 5 CTS -> ~B.CTS
+ * 6 6 DSR -> ~A.SYNC
+ * 8 CD -> ~B.DCD
+ * 12 DSRS(DCE) -> ~A.CTS (*)
+ * 15 TxC -> B.TxC
+ * 17 RxC -> B.RxC
+ * 20 1 DTR <- ~A.DTR
+ * 22 RI -> ~A.DCD
+ * 23 DSRS(DTE) <- ~B.RTS
+ *
+ * (*) EIA-232 defines the signal at this pin to be SCD, while DSRS(DCE)
+ * is shared with DSRS(DTE) at pin 23.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/timer.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/mm.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#ifdef CONFIG_SERIAL_DEC_CONSOLE
+#include <linux/console.h>
+#endif
+
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/bootinfo.h>
+#include <asm/dec/serial.h>
+
+#ifdef CONFIG_MACH_DECSTATION
+#include <asm/dec/interrupts.h>
+#include <asm/dec/machtype.h>
+#include <asm/dec/tc.h>
+#include <asm/dec/ioasic_addrs.h>
+#endif
+#ifdef CONFIG_KGDB
+#include <asm/kgdb.h>
+#endif
+#ifdef CONFIG_MAGIC_SYSRQ
+#include <linux/sysrq.h>
+#endif
+
+#include "zs.h"
+
+/*
+ * It would be nice to dynamically allocate everything that
+ * depends on NUM_SERIAL, so we could support any number of
+ * Z8530s, but for now...
+ */
+#define NUM_SERIAL 2 /* Max number of ZS chips supported */
+#define NUM_CHANNELS (NUM_SERIAL * 2) /* 2 channels per chip */
+#define CHANNEL_A_NR (zs_parms->channel_a_offset > zs_parms->channel_b_offset)
+ /* Number of channel A in the chip */
+#define ZS_CHAN_IO_SIZE 8
+#define ZS_CLOCK 7372800 /* Z8530 RTxC input clock rate */
+
+#define RECOVERY_DELAY udelay(2)
+
+struct zs_parms {
+ unsigned long scc0;
+ unsigned long scc1;
+ int channel_a_offset;
+ int channel_b_offset;
+ int irq0;
+ int irq1;
+ int clock;
+};
+
+static struct zs_parms *zs_parms;
+
+#ifdef CONFIG_MACH_DECSTATION
+static struct zs_parms ds_parms = {
+ scc0 : IOASIC_SCC0,
+ scc1 : IOASIC_SCC1,
+ channel_a_offset : 1,
+ channel_b_offset : 9,
+ irq0 : -1,
+ irq1 : -1,
+ clock : ZS_CLOCK
+};
+#endif
+
+#ifdef CONFIG_MACH_DECSTATION
+#define DS_BUS_PRESENT (IOASIC)
+#else
+#define DS_BUS_PRESENT 0
+#endif
+
+#define BUS_PRESENT (DS_BUS_PRESENT)
+
+struct dec_zschannel zs_channels[NUM_CHANNELS];
+struct dec_serial zs_soft[NUM_CHANNELS];
+int zs_channels_found;
+struct dec_serial *zs_chain; /* list of all channels */
+
+struct tty_struct zs_ttys[NUM_CHANNELS];
+
+#ifdef CONFIG_SERIAL_DEC_CONSOLE
+static struct console sercons;
+#endif
+#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
+ !defined(MODULE)
+static unsigned long break_pressed; /* break, really ... */
+#endif
+
+static unsigned char zs_init_regs[16] __initdata = {
+ 0, /* write 0 */
+ 0, /* write 1 */
+ 0, /* write 2 */
+ 0, /* write 3 */
+ (X16CLK), /* write 4 */
+ 0, /* write 5 */
+ 0, 0, 0, /* write 6, 7, 8 */
+ (MIE | DLC | NV), /* write 9 */
+ (NRZ), /* write 10 */
+ (TCBR | RCBR), /* write 11 */
+ 0, 0, /* BRG time constant, write 12 + 13 */
+ (BRSRC | BRENABL), /* write 14 */
+ 0 /* write 15 */
+};
+
+DECLARE_TASK_QUEUE(tq_zs_serial);
+
+static struct tty_driver *serial_driver;
+
+/* serial subtype definitions */
+#define SERIAL_TYPE_NORMAL 1
+
+/* number of characters left in xmit buffer before we ask for more */
+#define WAKEUP_CHARS 256
+
+/*
+ * Debugging.
+ */
+#undef SERIAL_DEBUG_OPEN
+#undef SERIAL_DEBUG_FLOW
+#undef SERIAL_DEBUG_THROTTLE
+#undef SERIAL_PARANOIA_CHECK
+
+#undef ZS_DEBUG_REGS
+
+#ifdef SERIAL_DEBUG_THROTTLE
+#define _tty_name(tty,buf) tty_name(tty,buf)
+#endif
+
+#define RS_STROBE_TIME 10
+#define RS_ISR_PASS_LIMIT 256
+
+#define _INLINE_ inline
+
+static void probe_sccs(void);
+static void change_speed(struct dec_serial *info);
+static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
+
+/*
+ * 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 unsigned char tmp_buf[4096]; /* This is cheating */
+static DECLARE_MUTEX(tmp_buf_sem);
+
+static inline int serial_paranoia_check(struct dec_serial *info,
+ char *name, const char *routine)
+{
+#ifdef SERIAL_PARANOIA_CHECK
+ static const char *badmagic =
+ "Warning: bad magic number for serial struct %s in %s\n";
+ static const char *badinfo =
+ "Warning: null mac_serial for %s in %s\n";
+
+ if (!info) {
+ printk(badinfo, name, routine);
+ return 1;
+ }
+ if (info->magic != SERIAL_MAGIC) {
+ printk(badmagic, name, routine);
+ return 1;
+ }
+#endif
+ return 0;
+}
+
+/*
+ * This is used to figure out the divisor speeds and the timeouts
+ */
+static int baud_table[] = {
+ 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
+ 9600, 19200, 38400, 57600, 115200, 0 };
+
+/*
+ * Reading and writing Z8530 registers.
+ */
+static inline unsigned char read_zsreg(struct dec_zschannel *channel,
+ unsigned char reg)
+{
+ unsigned char retval;
+
+ if (reg != 0) {
+ *channel->control = reg & 0xf;
+ fast_iob(); RECOVERY_DELAY;
+ }
+ retval = *channel->control;
+ RECOVERY_DELAY;
+ return retval;
+}
+
+static inline void write_zsreg(struct dec_zschannel *channel,
+ unsigned char reg, unsigned char value)
+{
+ if (reg != 0) {
+ *channel->control = reg & 0xf;
+ fast_iob(); RECOVERY_DELAY;
+ }
+ *channel->control = value;
+ fast_iob(); RECOVERY_DELAY;
+ return;
+}
+
+static inline unsigned char read_zsdata(struct dec_zschannel *channel)
+{
+ unsigned char retval;
+
+ retval = *channel->data;
+ RECOVERY_DELAY;
+ return retval;
+}
+
+static inline void write_zsdata(struct dec_zschannel *channel,
+ unsigned char value)
+{
+ *channel->data = value;
+ fast_iob(); RECOVERY_DELAY;
+ return;
+}
+
+static inline void load_zsregs(struct dec_zschannel *channel,
+ unsigned char *regs)
+{
+/* ZS_CLEARERR(channel);
+ ZS_CLEARFIFO(channel); */
+ /* Load 'em up */
+ write_zsreg(channel, R3, regs[R3] & ~RxENABLE);
+ write_zsreg(channel, R5, regs[R5] & ~TxENAB);
+ write_zsreg(channel, R4, regs[R4]);
+ write_zsreg(channel, R9, regs[R9]);
+ write_zsreg(channel, R1, regs[R1]);
+ write_zsreg(channel, R2, regs[R2]);
+ write_zsreg(channel, R10, regs[R10]);
+ write_zsreg(channel, R11, regs[R11]);
+ write_zsreg(channel, R12, regs[R12]);
+ write_zsreg(channel, R13, regs[R13]);
+ write_zsreg(channel, R14, regs[R14]);
+ write_zsreg(channel, R15, regs[R15]);
+ write_zsreg(channel, R3, regs[R3]);
+ write_zsreg(channel, R5, regs[R5]);
+ return;
+}
+
+/* Sets or clears DTR/RTS on the requested line */
+static inline void zs_rtsdtr(struct dec_serial *info, int which, int set)
+{
+ unsigned long flags;
+
+
+ save_flags(flags); cli();
+ if (info->zs_channel != info->zs_chan_a) {
+ if (set) {
+ info->zs_chan_a->curregs[5] |= (which & (RTS | DTR));
+ } else {
+ info->zs_chan_a->curregs[5] &= ~(which & (RTS | DTR));
+ }
+ write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
+ }
+ restore_flags(flags);
+}
+
+/* Utility routines for the Zilog */
+static inline int get_zsbaud(struct dec_serial *ss)
+{
+ struct dec_zschannel *channel = ss->zs_channel;
+ int brg;
+
+ /* The baud rate is split up between two 8-bit registers in
+ * what is termed 'BRG time constant' format in my docs for
+ * the chip, it is a function of the clk rate the chip is
+ * receiving which happens to be constant.
+ */
+ brg = (read_zsreg(channel, 13) << 8);
+ brg |= read_zsreg(channel, 12);
+ return BRG_TO_BPS(brg, (zs_parms->clock/(ss->clk_divisor)));
+}
+
+/* On receive, this clears errors and the receiver interrupts */
+static inline void rs_recv_clear(struct dec_zschannel *zsc)
+{
+ write_zsreg(zsc, 0, ERR_RES);
+ write_zsreg(zsc, 0, RES_H_IUS); /* XXX this is unnecessary */
+}
+
+/*
+ * ----------------------------------------------------------------------
+ *
+ * Here starts the interrupt handling routines. All of the following
+ * subroutines are declared as inline and are folded into
+ * rs_interrupt(). They were separated out for readability's sake.
+ *
+ * - Ted Ts'o (tytso@mit.edu), 7-Mar-93
+ * -----------------------------------------------------------------------
+ */
+
+/*
+ * This routine is used by the interrupt handler to schedule
+ * processing in the software interrupt portion of the driver.
+ */
+static _INLINE_ void rs_sched_event(struct dec_serial *info,
+ int event)
+{
+ info->event |= 1 << event;
+ queue_task(&info->tqueue, &tq_zs_serial);
+ mark_bh(SERIAL_BH);
+}
+
+static _INLINE_ void receive_chars(struct dec_serial *info,
+ struct pt_regs *regs)
+{
+ struct tty_struct *tty = info->tty;
+ unsigned char ch, stat, flag;
+
+ while ((read_zsreg(info->zs_channel, R0) & Rx_CH_AV) != 0) {
+
+ stat = read_zsreg(info->zs_channel, R1);
+ ch = read_zsdata(info->zs_channel);
+
+ if (!tty && (!info->hook || !info->hook->rx_char))
+ continue;
+
+ flag = TTY_NORMAL;
+ if (info->tty_break) {
+ info->tty_break = 0;
+ flag = TTY_BREAK;
+ if (info->flags & ZILOG_SAK)
+ do_SAK(tty);
+ /* Ignore the null char got when BREAK is removed. */
+ if (ch == 0)
+ continue;
+ } else {
+ if (stat & Rx_OVR) {
+ flag = TTY_OVERRUN;
+ } else if (stat & FRM_ERR) {
+ flag = TTY_FRAME;
+ } else if (stat & PAR_ERR) {
+ flag = TTY_PARITY;
+ }
+ if (flag != TTY_NORMAL)
+ /* reset the error indication */
+ write_zsreg(info->zs_channel, R0, ERR_RES);
+ }
+
+#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
+ !defined(MODULE)
+ if (break_pressed && info->line == sercons.index) {
+ /* Ignore the null char got when BREAK is removed. */
+ if (ch == 0)
+ continue;
+ if (time_before(jiffies, break_pressed + HZ * 5)) {
+ handle_sysrq(ch, regs, NULL);
+ break_pressed = 0;
+ continue;
+ }
+ break_pressed = 0;
+ }
+#endif
+
+ if (info->hook && info->hook->rx_char) {
+ (*info->hook->rx_char)(ch, flag);
+ return;
+ }
+
+ tty_insert_flip_char(tty, ch, flag);
+ }
+ if (tty)
+ tty_flip_buffer_push(tty);
+}
+
+static void transmit_chars(struct dec_serial *info)
+{
+ if ((read_zsreg(info->zs_channel, R0) & Tx_BUF_EMP) == 0)
+ return;
+ info->tx_active = 0;
+
+ if (info->x_char) {
+ /* Send next char */
+ write_zsdata(info->zs_channel, info->x_char);
+ info->x_char = 0;
+ info->tx_active = 1;
+ return;
+ }
+
+ if ((info->xmit_cnt <= 0) || (info->tty && info->tty->stopped)
+ || info->tx_stopped) {
+ write_zsreg(info->zs_channel, R0, RES_Tx_P);
+ return;
+ }
+ /* Send char */
+ write_zsdata(info->zs_channel, info->xmit_buf[info->xmit_tail++]);
+ info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
+ info->xmit_cnt--;
+ info->tx_active = 1;
+
+ if (info->xmit_cnt < WAKEUP_CHARS)
+ rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
+}
+
+static _INLINE_ void status_handle(struct dec_serial *info)
+{
+ unsigned char stat;
+
+ /* Get status from Read Register 0 */
+ stat = read_zsreg(info->zs_channel, R0);
+
+ if ((stat & BRK_ABRT) && !(info->read_reg_zero & BRK_ABRT)) {
+#if defined(CONFIG_SERIAL_DEC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) && \
+ !defined(MODULE)
+ if (info->line == sercons.index) {
+ if (!break_pressed)
+ break_pressed = jiffies;
+ } else
+#endif
+ info->tty_break = 1;
+ }
+
+ if (info->zs_channel != info->zs_chan_a) {
+
+ /* Check for DCD transitions */
+ if (info->tty && !C_CLOCAL(info->tty) &&
+ ((stat ^ info->read_reg_zero) & DCD) != 0 ) {
+ if (stat & DCD) {
+ wake_up_interruptible(&info->open_wait);
+ } else {
+ tty_hangup(info->tty);
+ }
+ }
+
+ /* Check for CTS transitions */
+ if (info->tty && C_CRTSCTS(info->tty)) {
+ if ((stat & CTS) != 0) {
+ if (info->tx_stopped) {
+ info->tx_stopped = 0;
+ if (!info->tx_active)
+ transmit_chars(info);
+ }
+ } else {
+ info->tx_stopped = 1;
+ }
+ }
+
+ }
+
+ /* Clear status condition... */
+ write_zsreg(info->zs_channel, R0, RES_EXT_INT);
+ info->read_reg_zero = stat;
+}
+
+/*
+ * This is the serial driver's generic interrupt routine
+ */
+void rs_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+ struct dec_serial *info = (struct dec_serial *) dev_id;
+ unsigned char zs_intreg;
+ int shift;
+
+ /* NOTE: The read register 3, which holds the irq status,
+ * does so for both channels on each chip. Although
+ * the status value itself must be read from the A
+ * channel and is only valid when read from channel A.
+ * Yes... broken hardware...
+ */
+#define CHAN_IRQMASK (CHBRxIP | CHBTxIP | CHBEXT)
+
+ if (info->zs_chan_a == info->zs_channel)
+ shift = 3; /* Channel A */
+ else
+ shift = 0; /* Channel B */
+
+ for (;;) {
+ zs_intreg = read_zsreg(info->zs_chan_a, R3) >> shift;
+ if ((zs_intreg & CHAN_IRQMASK) == 0)
+ break;
+
+ if (zs_intreg & CHBRxIP) {
+ receive_chars(info, regs);
+ }
+ if (zs_intreg & CHBTxIP) {
+ transmit_chars(info);
+ }
+ if (zs_intreg & CHBEXT) {
+ status_handle(info);
+ }
+ }
+
+ /* Why do we need this ? */
+ write_zsreg(info->zs_channel, 0, RES_H_IUS);
+}
+
+#ifdef ZS_DEBUG_REGS
+void zs_dump (void) {
+ int i, j;
+ for (i = 0; i < zs_channels_found; i++) {
+ struct dec_zschannel *ch = &zs_channels[i];
+ if ((long)ch->control == UNI_IO_BASE+UNI_SCC1A_CTRL) {
+ for (j = 0; j < 15; j++) {
+ printk("W%d = 0x%x\t",
+ j, (int)ch->curregs[j]);
+ }
+ for (j = 0; j < 15; j++) {
+ printk("R%d = 0x%x\t",
+ j, (int)read_zsreg(ch,j));
+ }
+ printk("\n\n");
+ }
+ }
+}
+#endif
+
+/*
+ * -------------------------------------------------------------------
+ * Here ends the serial interrupt routines.
+ * -------------------------------------------------------------------
+ */
+
+/*
+ * ------------------------------------------------------------
+ * rs_stop() and rs_start()
+ *
+ * This routines are called before setting or resetting tty->stopped.
+ * ------------------------------------------------------------
+ */
+static void rs_stop(struct tty_struct *tty)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+ unsigned long flags;
+
+ if (serial_paranoia_check(info, tty->name, "rs_stop"))
+ return;
+
+#if 1
+ save_flags(flags); cli();
+ if (info->zs_channel->curregs[5] & TxENAB) {
+ info->zs_channel->curregs[5] &= ~TxENAB;
+ write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
+ }
+ restore_flags(flags);
+#endif
+}
+
+static void rs_start(struct tty_struct *tty)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+ unsigned long flags;
+
+ if (serial_paranoia_check(info, tty->name, "rs_start"))
+ return;
+
+ save_flags(flags); cli();
+#if 1
+ if (info->xmit_cnt && info->xmit_buf && !(info->zs_channel->curregs[5] & TxENAB)) {
+ info->zs_channel->curregs[5] |= TxENAB;
+ write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
+ }
+#else
+ if (info->xmit_cnt && info->xmit_buf && !info->tx_active) {
+ transmit_chars(info);
+ }
+#endif
+ restore_flags(flags);
+}
+
+/*
+ * This routine is used to handle the "bottom half" processing for the
+ * serial driver, known also the "software interrupt" processing.
+ * This processing is done at the kernel interrupt level, after the
+ * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON. This
+ * is where time-consuming activities which can not be done in the
+ * interrupt driver proper are done; the interrupt driver schedules
+ * them using rs_sched_event(), and they get done here.
+ */
+static void do_serial_bh(void)
+{
+ run_task_queue(&tq_zs_serial);
+}
+
+static void do_softint(void *private_)
+{
+ struct dec_serial *info = (struct dec_serial *) private_;
+ struct tty_struct *tty;
+
+ tty = info->tty;
+ if (!tty)
+ return;
+
+ if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
+ tty_wakeup(tty);
+ }
+}
+
+int zs_startup(struct dec_serial * info)
+{
+ unsigned long flags;
+
+ if (info->flags & ZILOG_INITIALIZED)
+ return 0;
+
+ if (!info->xmit_buf) {
+ info->xmit_buf = (unsigned char *) get_zeroed_page(GFP_KERNEL);
+ if (!info->xmit_buf)
+ return -ENOMEM;
+ }
+
+ save_flags(flags); cli();
+
+#ifdef SERIAL_DEBUG_OPEN
+ printk("starting up ttyS%d (irq %d)...", info->line, info->irq);
+#endif
+
+ /*
+ * Clear the receive FIFO.
+ */
+ ZS_CLEARFIFO(info->zs_channel);
+ info->xmit_fifo_size = 1;
+
+ /*
+ * Clear the interrupt registers.
+ */
+ write_zsreg(info->zs_channel, R0, ERR_RES);
+ write_zsreg(info->zs_channel, R0, RES_H_IUS);
+
+ /*
+ * Set the speed of the serial port
+ */
+ change_speed(info);
+
+ /*
+ * Turn on RTS and DTR.
+ */
+ zs_rtsdtr(info, RTS | DTR, 1);
+
+ /*
+ * Finally, enable sequencing and interrupts
+ */
+ info->zs_channel->curregs[R1] &= ~RxINT_MASK;
+ info->zs_channel->curregs[R1] |= (RxINT_ALL | TxINT_ENAB |
+ EXT_INT_ENAB);
+ info->zs_channel->curregs[R3] |= RxENABLE;
+ info->zs_channel->curregs[R5] |= TxENAB;
+ info->zs_channel->curregs[R15] |= (DCDIE | CTSIE | TxUIE | BRKIE);
+ write_zsreg(info->zs_channel, R1, info->zs_channel->curregs[R1]);
+ write_zsreg(info->zs_channel, R3, info->zs_channel->curregs[R3]);
+ write_zsreg(info->zs_channel, R5, info->zs_channel->curregs[R5]);
+ write_zsreg(info->zs_channel, R15, info->zs_channel->curregs[R15]);
+
+ /*
+ * And clear the interrupt registers again for luck.
+ */
+ write_zsreg(info->zs_channel, R0, ERR_RES);
+ write_zsreg(info->zs_channel, R0, RES_H_IUS);
+
+ /* Save the current value of RR0 */
+ info->read_reg_zero = read_zsreg(info->zs_channel, R0);
+
+ if (info->tty)
+ clear_bit(TTY_IO_ERROR, &info->tty->flags);
+ info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+
+ info->flags |= ZILOG_INITIALIZED;
+ restore_flags(flags);
+ return 0;
+}
+
+/*
+ * 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 shutdown(struct dec_serial * info)
+{
+ unsigned long flags;
+
+ if (!(info->flags & ZILOG_INITIALIZED))
+ return;
+
+#ifdef SERIAL_DEBUG_OPEN
+ printk("Shutting down serial port %d (irq %d)....", info->line,
+ info->irq);
+#endif
+
+ save_flags(flags); cli(); /* Disable interrupts */
+
+ if (info->xmit_buf) {
+ free_page((unsigned long) info->xmit_buf);
+ info->xmit_buf = 0;
+ }
+
+ info->zs_channel->curregs[1] = 0;
+ write_zsreg(info->zs_channel, 1, info->zs_channel->curregs[1]); /* no interrupts */
+
+ info->zs_channel->curregs[3] &= ~RxENABLE;
+ write_zsreg(info->zs_channel, 3, info->zs_channel->curregs[3]);
+
+ info->zs_channel->curregs[5] &= ~TxENAB;
+ write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
+ if (!info->tty || C_HUPCL(info->tty)) {
+ zs_rtsdtr(info, RTS | DTR, 0);
+ }
+
+ if (info->tty)
+ set_bit(TTY_IO_ERROR, &info->tty->flags);
+
+ info->flags &= ~ZILOG_INITIALIZED;
+ restore_flags(flags);
+}
+
+/*
+ * This routine is called to set the UART divisor registers to match
+ * the specified baud rate for a serial port.
+ */
+static void change_speed(struct dec_serial *info)
+{
+ unsigned cflag;
+ int i;
+ int brg, bits;
+ unsigned long flags;
+
+ if (!info->hook) {
+ if (!info->tty || !info->tty->termios)
+ return;
+ cflag = info->tty->termios->c_cflag;
+ if (!info->port)
+ return;
+ } else {
+ cflag = info->hook->cflags;
+ }
+
+ i = cflag & CBAUD;
+ if (i & CBAUDEX) {
+ i &= ~CBAUDEX;
+ if (i < 1 || i > 2) {
+ if (!info->hook)
+ info->tty->termios->c_cflag &= ~CBAUDEX;
+ else
+ info->hook->cflags &= ~CBAUDEX;
+ } else
+ i += 15;
+ }
+
+ save_flags(flags); cli();
+ info->zs_baud = baud_table[i];
+ if (info->zs_baud) {
+ brg = BPS_TO_BRG(info->zs_baud, zs_parms->clock/info->clk_divisor);
+ info->zs_channel->curregs[12] = (brg & 255);
+ info->zs_channel->curregs[13] = ((brg >> 8) & 255);
+ zs_rtsdtr(info, DTR, 1);
+ } else {
+ zs_rtsdtr(info, RTS | DTR, 0);
+ return;
+ }
+
+ /* byte size and parity */
+ info->zs_channel->curregs[3] &= ~RxNBITS_MASK;
+ info->zs_channel->curregs[5] &= ~TxNBITS_MASK;
+ switch (cflag & CSIZE) {
+ case CS5:
+ bits = 7;
+ info->zs_channel->curregs[3] |= Rx5;
+ info->zs_channel->curregs[5] |= Tx5;
+ break;
+ case CS6:
+ bits = 8;
+ info->zs_channel->curregs[3] |= Rx6;
+ info->zs_channel->curregs[5] |= Tx6;
+ break;
+ case CS7:
+ bits = 9;
+ info->zs_channel->curregs[3] |= Rx7;
+ info->zs_channel->curregs[5] |= Tx7;
+ break;
+ case CS8:
+ default: /* defaults to 8 bits */
+ bits = 10;
+ info->zs_channel->curregs[3] |= Rx8;
+ info->zs_channel->curregs[5] |= Tx8;
+ break;
+ }
+
+ info->timeout = ((info->xmit_fifo_size*HZ*bits) / info->zs_baud);
+ info->timeout += HZ/50; /* Add .02 seconds of slop */
+
+ info->zs_channel->curregs[4] &= ~(SB_MASK | PAR_ENA | PAR_EVEN);
+ if (cflag & CSTOPB) {
+ info->zs_channel->curregs[4] |= SB2;
+ } else {
+ info->zs_channel->curregs[4] |= SB1;
+ }
+ if (cflag & PARENB) {
+ info->zs_channel->curregs[4] |= PAR_ENA;
+ }
+ if (!(cflag & PARODD)) {
+ info->zs_channel->curregs[4] |= PAR_EVEN;
+ }
+
+ if (!(cflag & CLOCAL)) {
+ if (!(info->zs_channel->curregs[15] & DCDIE))
+ info->read_reg_zero = read_zsreg(info->zs_channel, 0);
+ info->zs_channel->curregs[15] |= DCDIE;
+ } else
+ info->zs_channel->curregs[15] &= ~DCDIE;
+ if (cflag & CRTSCTS) {
+ info->zs_channel->curregs[15] |= CTSIE;
+ if ((read_zsreg(info->zs_channel, 0) & CTS) == 0)
+ info->tx_stopped = 1;
+ } else {
+ info->zs_channel->curregs[15] &= ~CTSIE;
+ info->tx_stopped = 0;
+ }
+
+ /* Load up the new values */
+ load_zsregs(info->zs_channel, info->zs_channel->curregs);
+
+ restore_flags(flags);
+}
+
+static void rs_flush_chars(struct tty_struct *tty)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+ unsigned long flags;
+
+ if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
+ return;
+
+ if (info->xmit_cnt <= 0 || tty->stopped || info->tx_stopped ||
+ !info->xmit_buf)
+ return;
+
+ /* Enable transmitter */
+ save_flags(flags); cli();
+ transmit_chars(info);
+ restore_flags(flags);
+}
+
+static int rs_write(struct tty_struct * tty,
+ const unsigned char *buf, int count)
+{
+ int c, total = 0;
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+ unsigned long flags;
+
+ if (serial_paranoia_check(info, tty->name, "rs_write"))
+ return 0;
+
+ if (!tty || !info->xmit_buf)
+ return 0;
+
+ save_flags(flags);
+ while (1) {
+ cli();
+ c = min(count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
+ SERIAL_XMIT_SIZE - info->xmit_head));
+ if (c <= 0)
+ break;
+
+ if (from_user) {
+ down(&tmp_buf_sem);
+ copy_from_user(tmp_buf, buf, c);
+ c = min(c, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
+ SERIAL_XMIT_SIZE - info->xmit_head));
+ memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
+ up(&tmp_buf_sem);
+ } else
+ memcpy(info->xmit_buf + info->xmit_head, buf, c);
+ info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
+ info->xmit_cnt += c;
+ restore_flags(flags);
+ buf += c;
+ count -= c;
+ total += c;
+ }
+
+ if (info->xmit_cnt && !tty->stopped && !info->tx_stopped
+ && !info->tx_active)
+ transmit_chars(info);
+ restore_flags(flags);
+ return total;
+}
+
+static int rs_write_room(struct tty_struct *tty)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+ int ret;
+
+ if (serial_paranoia_check(info, tty->name, "rs_write_room"))
+ return 0;
+ ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
+ if (ret < 0)
+ ret = 0;
+ return ret;
+}
+
+static int rs_chars_in_buffer(struct tty_struct *tty)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+
+ if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
+ return 0;
+ return info->xmit_cnt;
+}
+
+static void rs_flush_buffer(struct tty_struct *tty)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+
+ if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
+ return;
+ cli();
+ info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+ sti();
+ tty_wakeup(tty);
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_throttle()
+ *
+ * This routine is called by the upper-layer tty layer to signal that
+ * incoming characters should be throttled.
+ * ------------------------------------------------------------
+ */
+static void rs_throttle(struct tty_struct * tty)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+ unsigned long flags;
+
+#ifdef SERIAL_DEBUG_THROTTLE
+ char buf[64];
+
+ printk("throttle %s: %d....\n", _tty_name(tty, buf),
+ tty->ldisc.chars_in_buffer(tty));
+#endif
+
+ if (serial_paranoia_check(info, tty->name, "rs_throttle"))
+ return;
+
+ if (I_IXOFF(tty)) {
+ save_flags(flags); cli();
+ info->x_char = STOP_CHAR(tty);
+ if (!info->tx_active)
+ transmit_chars(info);
+ restore_flags(flags);
+ }
+
+ if (C_CRTSCTS(tty)) {
+ zs_rtsdtr(info, RTS, 0);
+ }
+}
+
+static void rs_unthrottle(struct tty_struct * tty)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+ unsigned long flags;
+
+#ifdef SERIAL_DEBUG_THROTTLE
+ char buf[64];
+
+ printk("unthrottle %s: %d....\n", _tty_name(tty, buf),
+ tty->ldisc.chars_in_buffer(tty));
+#endif
+
+ if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
+ return;
+
+ if (I_IXOFF(tty)) {
+ save_flags(flags); cli();
+ if (info->x_char)
+ info->x_char = 0;
+ else {
+ info->x_char = START_CHAR(tty);
+ if (!info->tx_active)
+ transmit_chars(info);
+ }
+ restore_flags(flags);
+ }
+
+ if (C_CRTSCTS(tty)) {
+ zs_rtsdtr(info, RTS, 1);
+ }
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_ioctl() and friends
+ * ------------------------------------------------------------
+ */
+
+static int get_serial_info(struct dec_serial * info,
+ struct serial_struct * retinfo)
+{
+ struct serial_struct tmp;
+
+ if (!retinfo)
+ return -EFAULT;
+ memset(&tmp, 0, sizeof(tmp));
+ tmp.type = info->type;
+ tmp.line = info->line;
+ tmp.port = info->port;
+ tmp.irq = info->irq;
+ tmp.flags = info->flags;
+ tmp.baud_base = info->baud_base;
+ tmp.close_delay = info->close_delay;
+ tmp.closing_wait = info->closing_wait;
+ tmp.custom_divisor = info->custom_divisor;
+ return copy_to_user(retinfo,&tmp,sizeof(*retinfo)) ? -EFAULT : 0;
+}
+
+static int set_serial_info(struct dec_serial * info,
+ struct serial_struct * new_info)
+{
+ struct serial_struct new_serial;
+ struct dec_serial old_info;
+ int retval = 0;
+
+ if (!new_info)
+ return -EFAULT;
+ copy_from_user(&new_serial,new_info,sizeof(new_serial));
+ old_info = *info;
+
+ if (!capable(CAP_SYS_ADMIN)) {
+ if ((new_serial.baud_base != info->baud_base) ||
+ (new_serial.type != info->type) ||
+ (new_serial.close_delay != info->close_delay) ||
+ ((new_serial.flags & ~ZILOG_USR_MASK) !=
+ (info->flags & ~ZILOG_USR_MASK)))
+ return -EPERM;
+ info->flags = ((info->flags & ~ZILOG_USR_MASK) |
+ (new_serial.flags & ZILOG_USR_MASK));
+ info->custom_divisor = new_serial.custom_divisor;
+ goto check_and_exit;
+ }
+
+ if (info->count > 1)
+ return -EBUSY;
+
+ /*
+ * OK, past this point, all the error checking has been done.
+ * At this point, we start making changes.....
+ */
+
+ info->baud_base = new_serial.baud_base;
+ info->flags = ((info->flags & ~ZILOG_FLAGS) |
+ (new_serial.flags & ZILOG_FLAGS));
+ info->type = new_serial.type;
+ info->close_delay = new_serial.close_delay;
+ info->closing_wait = new_serial.closing_wait;
+
+check_and_exit:
+ retval = zs_startup(info);
+ return retval;
+}
+
+/*
+ * get_lsr_info - get line status register info
+ *
+ * Purpose: Let user call ioctl() to get info when the UART physically
+ * is emptied. On bus types like RS485, the transmitter must
+ * release the bus after transmitting. This must be done when
+ * the transmit shift register is empty, not be done when the
+ * transmit holding register is empty. This functionality
+ * allows an RS485 driver to be written in user space.
+ */
+static int get_lsr_info(struct dec_serial * info, unsigned int *value)
+{
+ unsigned char status;
+
+ cli();
+ status = read_zsreg(info->zs_channel, 0);
+ sti();
+ put_user(status,value);
+ return 0;
+}
+
+static int rs_tiocmget(struct tty_struct *tty, struct file *file)
+{
+ struct dec_serial * info = (struct dec_serial *)tty->driver_data;
+ unsigned char control, status_a, status_b;
+ unsigned int result;
+
+ if (info->hook)
+ return -ENODEV;
+
+ if (serial_paranoia_check(info, tty->name, __FUNCTION__))
+ return -ENODEV;
+
+ if (tty->flags & (1 << TTY_IO_ERROR))
+ return -EIO;
+
+ if (info->zs_channel == info->zs_chan_a)
+ result = 0;
+ else {
+ cli();
+ control = info->zs_chan_a->curregs[5];
+ status_a = read_zsreg(info->zs_chan_a, 0);
+ status_b = read_zsreg(info->zs_channel, 0);
+ sti();
+ result = ((control & RTS) ? TIOCM_RTS: 0)
+ | ((control & DTR) ? TIOCM_DTR: 0)
+ | ((status_b & DCD) ? TIOCM_CAR: 0)
+ | ((status_a & DCD) ? TIOCM_RNG: 0)
+ | ((status_a & SYNC_HUNT) ? TIOCM_DSR: 0)
+ | ((status_b & CTS) ? TIOCM_CTS: 0);
+ }
+ return result;
+}
+
+static int rs_tiocmset(struct tty_struct *tty, struct file *file,
+ unsigned int set, unsigned int clear)
+{
+ struct dec_serial * info = (struct dec_serial *)tty->driver_data;
+ int error;
+ unsigned int arg, bits;
+
+ if (info->hook)
+ return -ENODEV;
+
+ if (serial_paranoia_check(info, tty->name, __FUNCTION__))
+ return -ENODEV;
+
+ if (tty->flags & (1 << TTY_IO_ERROR))
+ return -EIO;
+
+ if (info->zs_channel == info->zs_chan_a)
+ return 0;
+
+ get_user(arg, value);
+ cli();
+ if (set & TIOCM_RTS)
+ info->zs_chan_a->curregs[5] |= RTS;
+ if (set & TIOCM_DTR)
+ info->zs_chan_a->curregs[5] |= DTR;
+ if (clear & TIOCM_RTS)
+ info->zs_chan_a->curregs[5] &= ~RTS;
+ if (clear & TIOCM_DTR)
+ info->zs_chan_a->curregs[5] &= ~DTR;
+ write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
+ sti();
+ return 0;
+}
+
+/*
+ * rs_break - turn transmit break condition on/off
+ */
+static void rs_break(struct tty_struct *tty, int break_state)
+{
+ struct dec_serial *info = (struct dec_serial *) tty->driver_data;
+ unsigned long flags;
+
+ if (serial_paranoia_check(info, tty->name, "rs_break"))
+ return;
+ if (!info->port)
+ return;
+
+ save_flags(flags); cli();
+ if (break_state == -1)
+ info->zs_channel->curregs[5] |= SND_BRK;
+ else
+ info->zs_channel->curregs[5] &= ~SND_BRK;
+ write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
+ restore_flags(flags);
+}
+
+static int rs_ioctl(struct tty_struct *tty, struct file * file,
+ unsigned int cmd, unsigned long arg)
+{
+ int error;
+ struct dec_serial * info = (struct dec_serial *)tty->driver_data;
+
+ if (info->hook)
+ return -ENODEV;
+
+ if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
+ return -ENODEV;
+
+ if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
+ (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
+ (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
+ if (tty->flags & (1 << TTY_IO_ERROR))
+ return -EIO;
+ }
+
+ switch (cmd) {
+ case TIOCGSERIAL:
+ if (!access_ok(VERIFY_WRITE, (void *)arg,
+ sizeof(struct serial_struct)))
+ return -EFAULT;
+ 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 */
+ if (!access_ok(VERIFY_WRITE, (void *)arg,
+ sizeof(unsigned int)))
+ return -EFAULT;
+ return get_lsr_info(info, (unsigned int *)arg);
+
+ case TIOCSERGSTRUCT:
+ if (!access_ok(VERIFY_WRITE, (void *)arg,
+ sizeof(struct dec_serial)))
+ return -EFAULT;
+ copy_from_user((struct dec_serial *)arg, info,
+ sizeof(struct dec_serial));
+ return 0;
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return 0;
+}
+
+static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
+{
+ struct dec_serial *info = (struct dec_serial *)tty->driver_data;
+ int was_stopped;
+
+ if (tty->termios->c_cflag == old_termios->c_cflag)
+ return;
+ was_stopped = info->tx_stopped;
+
+ change_speed(info);
+
+ if (was_stopped && !info->tx_stopped)
+ rs_start(tty);
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_close()
+ *
+ * This routine is called when the serial port gets closed.
+ * Wait for the last remaining data to be sent.
+ * ------------------------------------------------------------
+ */
+static void rs_close(struct tty_struct *tty, struct file * filp)
+{
+ struct dec_serial * info = (struct dec_serial *)tty->driver_data;
+ unsigned long flags;
+
+ if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
+ return;
+
+ save_flags(flags); cli();
+
+ if (tty_hung_up_p(filp)) {
+ restore_flags(flags);
+ return;
+ }
+
+#ifdef SERIAL_DEBUG_OPEN
+ printk("rs_close ttyS%d, count = %d\n", info->line, info->count);
+#endif
+ if ((tty->count == 1) && (info->count != 1)) {
+ /*
+ * Uh, oh. tty->count is 1, which means that the tty
+ * structure will be freed. Info->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("rs_close: bad serial port count; tty->count is 1, "
+ "info->count is %d\n", info->count);
+ info->count = 1;
+ }
+ if (--info->count < 0) {
+ printk("rs_close: bad serial port count for ttyS%d: %d\n",
+ info->line, info->count);
+ info->count = 0;
+ }
+ if (info->count) {
+ restore_flags(flags);
+ return;
+ }
+ info->flags |= ZILOG_CLOSING;
+ /*
+ * 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->closing_wait != ZILOG_CLOSING_WAIT_NONE)
+ tty_wait_until_sent(tty, info->closing_wait);
+ /*
+ * At this point we stop accepting input. To do this, we
+ * disable the receiver and receive interrupts.
+ */
+ info->zs_channel->curregs[3] &= ~RxENABLE;
+ write_zsreg(info->zs_channel, 3, info->zs_channel->curregs[3]);
+ info->zs_channel->curregs[1] = 0; /* disable any rx ints */
+ write_zsreg(info->zs_channel, 1, info->zs_channel->curregs[1]);
+ ZS_CLEARFIFO(info->zs_channel);
+ if (info->flags & ZILOG_INITIALIZED) {
+ /*
+ * Before we drop DTR, make sure the SCC transmitter
+ * has completely drained.
+ */
+ rs_wait_until_sent(tty, info->timeout);
+ }
+
+ shutdown(info);
+ if (tty->driver->flush_buffer)
+ tty->driver->flush_buffer(tty);
+ tty_ldisc_flush(tty);
+ tty->closing = 0;
+ info->event = 0;
+ info->tty = 0;
+ if (info->blocked_open) {
+ if (info->close_delay) {
+ msleep_interruptible(jiffies_to_msecs(info->close_delay));
+ }
+ wake_up_interruptible(&info->open_wait);
+ }
+ info->flags &= ~(ZILOG_NORMAL_ACTIVE|ZILOG_CLOSING);
+ wake_up_interruptible(&info->close_wait);
+ restore_flags(flags);
+}
+
+/*
+ * rs_wait_until_sent() --- wait until the transmitter is empty
+ */
+static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+ struct dec_serial *info = (struct dec_serial *) tty->driver_data;
+ unsigned long orig_jiffies;
+ int char_time;
+
+ if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
+ return;
+
+ orig_jiffies = jiffies;
+ /*
+ * 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.
+ */
+ char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
+ char_time = char_time / 5;
+ if (char_time == 0)
+ char_time = 1;
+ if (timeout)
+ char_time = min(char_time, timeout);
+ while ((read_zsreg(info->zs_channel, 1) & Tx_BUF_EMP) == 0) {
+ msleep_interruptible(jiffies_to_msecs(char_time));
+ if (signal_pending(current))
+ break;
+ if (timeout && time_after(jiffies, orig_jiffies + timeout))
+ break;
+ }
+ current->state = TASK_RUNNING;
+}
+
+/*
+ * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
+ */
+void rs_hangup(struct tty_struct *tty)
+{
+ struct dec_serial * info = (struct dec_serial *)tty->driver_data;
+
+ if (serial_paranoia_check(info, tty->name, "rs_hangup"))
+ return;
+
+ rs_flush_buffer(tty);
+ shutdown(info);
+ info->event = 0;
+ info->count = 0;
+ info->flags &= ~ZILOG_NORMAL_ACTIVE;
+ info->tty = 0;
+ wake_up_interruptible(&info->open_wait);
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_open() and friends
+ * ------------------------------------------------------------
+ */
+static int block_til_ready(struct tty_struct *tty, struct file * filp,
+ struct dec_serial *info)
+{
+ DECLARE_WAITQUEUE(wait, current);
+ int retval;
+ int do_clocal = 0;
+
+ /*
+ * If the device is in the middle of being closed, then block
+ * until it's done, and then try again.
+ */
+ if (info->flags & ZILOG_CLOSING) {
+ interruptible_sleep_on(&info->close_wait);
+#ifdef SERIAL_DO_RESTART
+ return ((info->flags & ZILOG_HUP_NOTIFY) ?
+ -EAGAIN : -ERESTARTSYS);
+#else
+ return -EAGAIN;
+#endif
+ }
+
+ /*
+ * 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))) {
+ info->flags |= ZILOG_NORMAL_ACTIVE;
+ return 0;
+ }
+
+ 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, info->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);
+#ifdef SERIAL_DEBUG_OPEN
+ printk("block_til_ready before block: ttyS%d, count = %d\n",
+ info->line, info->count);
+#endif
+ cli();
+ if (!tty_hung_up_p(filp))
+ info->count--;
+ sti();
+ info->blocked_open++;
+ while (1) {
+ cli();
+ if (tty->termios->c_cflag & CBAUD)
+ zs_rtsdtr(info, RTS | DTR, 1);
+ sti();
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (tty_hung_up_p(filp) ||
+ !(info->flags & ZILOG_INITIALIZED)) {
+#ifdef SERIAL_DO_RESTART
+ if (info->flags & ZILOG_HUP_NOTIFY)
+ retval = -EAGAIN;
+ else
+ retval = -ERESTARTSYS;
+#else
+ retval = -EAGAIN;
+#endif
+ break;
+ }
+ if (!(info->flags & ZILOG_CLOSING) &&
+ (do_clocal || (read_zsreg(info->zs_channel, 0) & DCD)))
+ break;
+ if (signal_pending(current)) {
+ retval = -ERESTARTSYS;
+ break;
+ }
+#ifdef SERIAL_DEBUG_OPEN
+ printk("block_til_ready blocking: ttyS%d, count = %d\n",
+ info->line, info->count);
+#endif
+ schedule();
+ }
+ current->state = TASK_RUNNING;
+ remove_wait_queue(&info->open_wait, &wait);
+ if (!tty_hung_up_p(filp))
+ info->count++;
+ info->blocked_open--;
+#ifdef SERIAL_DEBUG_OPEN
+ printk("block_til_ready after blocking: ttyS%d, count = %d\n",
+ info->line, info->count);
+#endif
+ if (retval)
+ return retval;
+ info->flags |= ZILOG_NORMAL_ACTIVE;
+ return 0;
+}
+
+/*
+ * This routine is called whenever a serial port is opened. It
+ * enables interrupts for a serial port, linking in its ZILOG structure into
+ * the IRQ chain. It also performs the serial-specific
+ * initialization for the tty structure.
+ */
+int rs_open(struct tty_struct *tty, struct file * filp)
+{
+ struct dec_serial *info;
+ int retval, line;
+
+ line = tty->index;
+ if ((line < 0) || (line >= zs_channels_found))
+ return -ENODEV;
+ info = zs_soft + line;
+
+ if (info->hook)
+ return -ENODEV;
+
+ if (serial_paranoia_check(info, tty->name, "rs_open"))
+ return -ENODEV;
+#ifdef SERIAL_DEBUG_OPEN
+ printk("rs_open %s, count = %d\n", tty->name, info->count);
+#endif
+
+ info->count++;
+ tty->driver_data = info;
+ info->tty = tty;
+
+ /*
+ * If the port is the middle of closing, bail out now
+ */
+ if (tty_hung_up_p(filp) ||
+ (info->flags & ZILOG_CLOSING)) {
+ if (info->flags & ZILOG_CLOSING)
+ interruptible_sleep_on(&info->close_wait);
+#ifdef SERIAL_DO_RESTART
+ return ((info->flags & ZILOG_HUP_NOTIFY) ?
+ -EAGAIN : -ERESTARTSYS);
+#else
+ return -EAGAIN;
+#endif
+ }
+
+ /*
+ * Start up serial port
+ */
+ retval = zs_startup(info);
+ if (retval)
+ return retval;
+
+ retval = block_til_ready(tty, filp, info);
+ if (retval) {
+#ifdef SERIAL_DEBUG_OPEN
+ printk("rs_open returning after block_til_ready with %d\n",
+ retval);
+#endif
+ return retval;
+ }
+
+#ifdef CONFIG_SERIAL_DEC_CONSOLE
+ if (sercons.cflag && sercons.index == line) {
+ tty->termios->c_cflag = sercons.cflag;
+ sercons.cflag = 0;
+ change_speed(info);
+ }
+#endif
+
+#ifdef SERIAL_DEBUG_OPEN
+ printk("rs_open %s successful...", tty->name);
+#endif
+/* tty->low_latency = 1; */
+ return 0;
+}
+
+/* Finally, routines used to initialize the serial driver. */
+
+static void __init show_serial_version(void)
+{
+ printk("DECstation Z8530 serial driver version 0.09\n");
+}
+
+/* Initialize Z8530s zs_channels
+ */
+
+static void __init probe_sccs(void)
+{
+ struct dec_serial **pp;
+ int i, n, n_chips = 0, n_channels, chip, channel;
+ unsigned long flags;
+
+ /*
+ * did we get here by accident?
+ */
+ if(!BUS_PRESENT) {
+ printk("Not on JUNKIO machine, skipping probe_sccs\n");
+ return;
+ }
+
+ /*
+ * When serial console is activated, tc_init has not been called yet
+ * and system_base is undefined. Unfortunately we have to hardcode
+ * system_base for this case :-(. HK
+ */
+ switch(mips_machtype) {
+#ifdef CONFIG_MACH_DECSTATION
+ case MACH_DS5000_2X0:
+ case MACH_DS5900:
+ system_base = KSEG1ADDR(0x1f800000);
+ n_chips = 2;
+ zs_parms = &ds_parms;
+ zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
+ zs_parms->irq1 = dec_interrupt[DEC_IRQ_SCC1];
+ break;
+ case MACH_DS5000_1XX:
+ system_base = KSEG1ADDR(0x1c000000);
+ n_chips = 2;
+ zs_parms = &ds_parms;
+ zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
+ zs_parms->irq1 = dec_interrupt[DEC_IRQ_SCC1];
+ break;
+ case MACH_DS5000_XX:
+ system_base = KSEG1ADDR(0x1c000000);
+ n_chips = 1;
+ zs_parms = &ds_parms;
+ zs_parms->irq0 = dec_interrupt[DEC_IRQ_SCC0];
+ break;
+#endif
+ default:
+ panic("zs: unsupported bus");
+ }
+ if (!zs_parms)
+ panic("zs: uninitialized parms");
+
+ pp = &zs_chain;
+
+ n_channels = 0;
+
+ for (chip = 0; chip < n_chips; chip++) {
+ for (channel = 0; channel <= 1; channel++) {
+ /*
+ * The sccs reside on the high byte of the 16 bit IOBUS
+ */
+ zs_channels[n_channels].control =
+ (volatile unsigned char *)system_base +
+ (0 == chip ? zs_parms->scc0 : zs_parms->scc1) +
+ (0 == channel ? zs_parms->channel_a_offset :
+ zs_parms->channel_b_offset);
+ zs_channels[n_channels].data =
+ zs_channels[n_channels].control + 4;
+
+#ifndef CONFIG_SERIAL_DEC_CONSOLE
+ /*
+ * We're called early and memory managment isn't up, yet.
+ * Thus check_region would fail.
+ */
+ if (!request_region((unsigned long)
+ zs_channels[n_channels].control,
+ ZS_CHAN_IO_SIZE, "SCC"))
+ panic("SCC I/O region is not free");
+#endif
+ zs_soft[n_channels].zs_channel = &zs_channels[n_channels];
+ /* HACK alert! */
+ if (!(chip & 1))
+ zs_soft[n_channels].irq = zs_parms->irq0;
+ else
+ zs_soft[n_channels].irq = zs_parms->irq1;
+
+ /*
+ * Identification of channel A. Location of channel A
+ * inside chip depends on mapping of internal address
+ * the chip decodes channels by.
+ * CHANNEL_A_NR returns either 0 (in case of
+ * DECstations) or 1 (in case of Baget).
+ */
+ if (CHANNEL_A_NR == channel)
+ zs_soft[n_channels].zs_chan_a =
+ &zs_channels[n_channels+1-2*CHANNEL_A_NR];
+ else
+ zs_soft[n_channels].zs_chan_a =
+ &zs_channels[n_channels];
+
+ *pp = &zs_soft[n_channels];
+ pp = &zs_soft[n_channels].zs_next;
+ n_channels++;
+ }
+ }
+
+ *pp = 0;
+ zs_channels_found = n_channels;
+
+ for (n = 0; n < zs_channels_found; n++) {
+ for (i = 0; i < 16; i++) {
+ zs_soft[n].zs_channel->curregs[i] = zs_init_regs[i];
+ }
+ }
+
+ save_and_cli(flags);
+ for (n = 0; n < zs_channels_found; n++) {
+ if (n % 2 == 0) {
+ write_zsreg(zs_soft[n].zs_chan_a, R9, FHWRES);
+ udelay(10);
+ write_zsreg(zs_soft[n].zs_chan_a, R9, 0);
+ }
+ load_zsregs(zs_soft[n].zs_channel,
+ zs_soft[n].zs_channel->curregs);
+ }
+ restore_flags(flags);
+}
+
+static struct tty_operations serial_ops = {
+ .open = rs_open,
+ .close = rs_close,
+ .write = rs_write,
+ .flush_chars = rs_flush_chars,
+ .write_room = rs_write_room,
+ .chars_in_buffer = rs_chars_in_buffer,
+ .flush_buffer = rs_flush_buffer,
+ .ioctl = rs_ioctl,
+ .throttle = rs_throttle,
+ .unthrottle = rs_unthrottle,
+ .set_termios = rs_set_termios,
+ .stop = rs_stop,
+ .start = rs_start,
+ .hangup = rs_hangup,
+ .break_ctl = rs_break,
+ .wait_until_sent = rs_wait_until_sent,
+ .tiocmget = rs_tiocmget,
+ .tiocmset = rs_tiocmset,
+};
+
+/* zs_init inits the driver */
+int __init zs_init(void)
+{
+ int channel, i;
+ struct dec_serial *info;
+
+ if(!BUS_PRESENT)
+ return -ENODEV;
+
+ /* Setup base handler, and timer table. */
+ init_bh(SERIAL_BH, do_serial_bh);
+
+ /* Find out how many Z8530 SCCs we have */
+ if (zs_chain == 0)
+ probe_sccs();
+ serial_driver = alloc_tty_driver(zs_channels_found);
+ if (!serial_driver)
+ return -ENOMEM;
+
+ show_serial_version();
+
+ /* Initialize the tty_driver structure */
+ /* Not all of this is exactly right for us. */
+
+ serial_driver->owner = THIS_MODULE;
+ serial_driver->devfs_name = "tts/";
+ serial_driver->name = "ttyS";
+ serial_driver->major = TTY_MAJOR;
+ serial_driver->minor_start = 64;
+ serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
+ serial_driver->subtype = SERIAL_TYPE_NORMAL;
+ serial_driver->init_termios = tty_std_termios;
+ serial_driver->init_termios.c_cflag =
+ B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+ serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS;
+ tty_set_operations(serial_driver, &serial_ops);
+
+ if (tty_register_driver(serial_driver))
+ panic("Couldn't register serial driver");
+
+ for (info = zs_chain, i = 0; info; info = info->zs_next, i++) {
+
+ /* Needed before interrupts are enabled. */
+ info->tty = 0;
+ info->x_char = 0;
+
+ if (info->hook && info->hook->init_info) {
+ (*info->hook->init_info)(info);
+ continue;
+ }
+
+ info->magic = SERIAL_MAGIC;
+ info->port = (int) info->zs_channel->control;
+ info->line = i;
+ info->custom_divisor = 16;
+ info->close_delay = 50;
+ info->closing_wait = 3000;
+ info->event = 0;
+ info->count = 0;
+ info->blocked_open = 0;
+ info->tqueue.routine = do_softint;
+ info->tqueue.data = info;
+ init_waitqueue_head(&info->open_wait);
+ init_waitqueue_head(&info->close_wait);
+ printk("ttyS%02d at 0x%08x (irq = %d) is a Z85C30 SCC\n",
+ info->line, info->port, info->irq);
+ tty_register_device(serial_driver, info->line, NULL);
+
+ }
+
+ for (channel = 0; channel < zs_channels_found; ++channel) {
+ zs_soft[channel].clk_divisor = 16;
+ zs_soft[channel].zs_baud = get_zsbaud(&zs_soft[channel]);
+
+ if (request_irq(zs_soft[channel].irq, rs_interrupt, SA_SHIRQ,
+ "scc", &zs_soft[channel]))
+ printk(KERN_ERR "decserial: can't get irq %d\n",
+ zs_soft[channel].irq);
+
+ if (zs_soft[channel].hook) {
+ zs_startup(&zs_soft[channel]);
+ if (zs_soft[channel].hook->init_channel)
+ (*zs_soft[channel].hook->init_channel)
+ (&zs_soft[channel]);
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * polling I/O routines
+ */
+static int
+zs_poll_tx_char(void *handle, unsigned char ch)
+{
+ struct dec_serial *info = handle;
+ struct dec_zschannel *chan = info->zs_channel;
+ int ret;
+
+ if(chan) {
+ int loops = 10000;
+
+ while (loops && !(read_zsreg(chan, 0) & Tx_BUF_EMP))
+ loops--;
+
+ if (loops) {
+ write_zsdata(chan, ch);
+ ret = 0;
+ } else
+ ret = -EAGAIN;
+
+ return ret;
+ } else
+ return -ENODEV;
+}
+
+static int
+zs_poll_rx_char(void *handle)
+{
+ struct dec_serial *info = handle;
+ struct dec_zschannel *chan = info->zs_channel;
+ int ret;
+
+ if(chan) {
+ int loops = 10000;
+
+ while (loops && !(read_zsreg(chan, 0) & Rx_CH_AV))
+ loops--;
+
+ if (loops)
+ ret = read_zsdata(chan);
+ else
+ ret = -EAGAIN;
+
+ return ret;
+ } else
+ return -ENODEV;
+}
+
+int register_zs_hook(unsigned int channel, struct dec_serial_hook *hook)
+{
+ struct dec_serial *info = &zs_soft[channel];
+
+ if (info->hook) {
+ printk("%s: line %d has already a hook registered\n",
+ __FUNCTION__, channel);
+
+ return 0;
+ } else {
+ hook->poll_rx_char = zs_poll_rx_char;
+ hook->poll_tx_char = zs_poll_tx_char;
+ info->hook = hook;
+
+ return 1;
+ }
+}
+
+int unregister_zs_hook(unsigned int channel)
+{
+ struct dec_serial *info = &zs_soft[channel];
+
+ if (info->hook) {
+ info->hook = NULL;
+ return 1;
+ } else {
+ printk("%s: trying to unregister hook on line %d,"
+ " but none is registered\n", __FUNCTION__, channel);
+ return 0;
+ }
+}
+
+/*
+ * ------------------------------------------------------------
+ * Serial console driver
+ * ------------------------------------------------------------
+ */
+#ifdef CONFIG_SERIAL_DEC_CONSOLE
+
+
+/*
+ * Print a string to the serial port trying not to disturb
+ * any possible real use of the port...
+ */
+static void serial_console_write(struct console *co, const char *s,
+ unsigned count)
+{
+ struct dec_serial *info;
+ int i;
+
+ info = zs_soft + co->index;
+
+ for (i = 0; i < count; i++, s++) {
+ if(*s == '\n')
+ zs_poll_tx_char(info, '\r');
+ zs_poll_tx_char(info, *s);
+ }
+}
+
+static struct tty_driver *serial_console_device(struct console *c, int *index)
+{
+ *index = c->index;
+ return serial_driver;
+}
+
+/*
+ * Setup initial baud/bits/parity. We do two things here:
+ * - construct a cflag setting for the first rs_open()
+ * - initialize the serial port
+ * Return non-zero if we didn't find a serial port.
+ */
+static int __init serial_console_setup(struct console *co, char *options)
+{
+ struct dec_serial *info;
+ int baud = 9600;
+ int bits = 8;
+ int parity = 'n';
+ int cflag = CREAD | HUPCL | CLOCAL;
+ int clk_divisor = 16;
+ int brg;
+ char *s;
+ unsigned long flags;
+
+ if(!BUS_PRESENT)
+ return -ENODEV;
+
+ info = zs_soft + co->index;
+
+ if (zs_chain == 0)
+ probe_sccs();
+
+ info->is_cons = 1;
+
+ if (options) {
+ baud = simple_strtoul(options, NULL, 10);
+ s = options;
+ 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;
+ case 19200:
+ cflag |= B19200;
+ break;
+ case 38400:
+ cflag |= B38400;
+ break;
+ case 57600:
+ cflag |= B57600;
+ break;
+ case 115200:
+ cflag |= B115200;
+ break;
+ case 9600:
+ default:
+ cflag |= B9600;
+ /*
+ * Set this to a sane value to prevent a divide error.
+ */
+ baud = 9600;
+ break;
+ }
+ switch(bits) {
+ case 7:
+ cflag |= CS7;
+ break;
+ default:
+ case 8:
+ cflag |= CS8;
+ break;
+ }
+ switch(parity) {
+ case 'o': case 'O':
+ cflag |= PARODD;
+ break;
+ case 'e': case 'E':
+ cflag |= PARENB;
+ break;
+ }
+ co->cflag = cflag;
+
+ save_and_cli(flags);
+
+ /*
+ * Set up the baud rate generator.
+ */
+ brg = BPS_TO_BRG(baud, zs_parms->clock / clk_divisor);
+ info->zs_channel->curregs[R12] = (brg & 255);
+ info->zs_channel->curregs[R13] = ((brg >> 8) & 255);
+
+ /*
+ * Set byte size and parity.
+ */
+ if (bits == 7) {
+ info->zs_channel->curregs[R3] |= Rx7;
+ info->zs_channel->curregs[R5] |= Tx7;
+ } else {
+ info->zs_channel->curregs[R3] |= Rx8;
+ info->zs_channel->curregs[R5] |= Tx8;
+ }
+ if (cflag & PARENB) {
+ info->zs_channel->curregs[R4] |= PAR_ENA;
+ }
+ if (!(cflag & PARODD)) {
+ info->zs_channel->curregs[R4] |= PAR_EVEN;
+ }
+ info->zs_channel->curregs[R4] |= SB1;
+
+ /*
+ * Turn on RTS and DTR.
+ */
+ zs_rtsdtr(info, RTS | DTR, 1);
+
+ /*
+ * Finally, enable sequencing.
+ */
+ info->zs_channel->curregs[R3] |= RxENABLE;
+ info->zs_channel->curregs[R5] |= TxENAB;
+
+ /*
+ * Clear the interrupt registers.
+ */
+ write_zsreg(info->zs_channel, R0, ERR_RES);
+ write_zsreg(info->zs_channel, R0, RES_H_IUS);
+
+ /*
+ * Load up the new values.
+ */
+ load_zsregs(info->zs_channel, info->zs_channel->curregs);
+
+ /* Save the current value of RR0 */
+ info->read_reg_zero = read_zsreg(info->zs_channel, R0);
+
+ zs_soft[co->index].clk_divisor = clk_divisor;
+ zs_soft[co->index].zs_baud = get_zsbaud(&zs_soft[co->index]);
+
+ restore_flags(flags);
+
+ return 0;
+}
+
+static struct console sercons = {
+ .name = "ttyS",
+ .write = serial_console_write,
+ .device = serial_console_device,
+ .setup = serial_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+};
+
+/*
+ * Register console.
+ */
+void __init zs_serial_console_init(void)
+{
+ register_console(&sercons);
+}
+#endif /* ifdef CONFIG_SERIAL_DEC_CONSOLE */
+
+#ifdef CONFIG_KGDB
+struct dec_zschannel *zs_kgdbchan;
+static unsigned char scc_inittab[] = {
+ 9, 0x80, /* reset A side (CHRA) */
+ 13, 0, /* set baud rate divisor */
+ 12, 1,
+ 14, 1, /* baud rate gen enable, src=rtxc (BRENABL) */
+ 11, 0x50, /* clocks = br gen (RCBR | TCBR) */
+ 5, 0x6a, /* tx 8 bits, assert RTS (Tx8 | TxENAB | RTS) */
+ 4, 0x44, /* x16 clock, 1 stop (SB1 | X16CLK)*/
+ 3, 0xc1, /* rx enable, 8 bits (RxENABLE | Rx8)*/
+};
+
+/* These are for receiving and sending characters under the kgdb
+ * source level kernel debugger.
+ */
+void putDebugChar(char kgdb_char)
+{
+ struct dec_zschannel *chan = zs_kgdbchan;
+ while ((read_zsreg(chan, 0) & Tx_BUF_EMP) == 0)
+ RECOVERY_DELAY;
+ write_zsdata(chan, kgdb_char);
+}
+char getDebugChar(void)
+{
+ struct dec_zschannel *chan = zs_kgdbchan;
+ while((read_zsreg(chan, 0) & Rx_CH_AV) == 0)
+ eieio(); /*barrier();*/
+ return read_zsdata(chan);
+}
+void kgdb_interruptible(int yes)
+{
+ struct dec_zschannel *chan = zs_kgdbchan;
+ int one, nine;
+ nine = read_zsreg(chan, 9);
+ if (yes == 1) {
+ one = EXT_INT_ENAB|RxINT_ALL;
+ nine |= MIE;
+ printk("turning serial ints on\n");
+ } else {
+ one = RxINT_DISAB;
+ nine &= ~MIE;
+ printk("turning serial ints off\n");
+ }
+ write_zsreg(chan, 1, one);
+ write_zsreg(chan, 9, nine);
+}
+
+static int kgdbhook_init_channel(void *handle)
+{
+ return 0;
+}
+
+static void kgdbhook_init_info(void *handle)
+{
+}
+
+static void kgdbhook_rx_char(void *handle, unsigned char ch, unsigned char fl)
+{
+ struct dec_serial *info = handle;
+
+ if (fl != TTY_NORMAL)
+ return;
+ if (ch == 0x03 || ch == '$')
+ breakpoint();
+}
+
+/* This sets up the serial port we're using, and turns on
+ * interrupts for that channel, so kgdb is usable once we're done.
+ */
+static inline void kgdb_chaninit(struct dec_zschannel *ms, int intson, int bps)
+{
+ int brg;
+ int i, x;
+ volatile char *sccc = ms->control;
+ brg = BPS_TO_BRG(bps, zs_parms->clock/16);
+ printk("setting bps on kgdb line to %d [brg=%x]\n", bps, brg);
+ for (i = 20000; i != 0; --i) {
+ x = *sccc; eieio();
+ }
+ for (i = 0; i < sizeof(scc_inittab); ++i) {
+ write_zsreg(ms, scc_inittab[i], scc_inittab[i+1]);
+ i++;
+ }
+}
+/* This is called at boot time to prime the kgdb serial debugging
+ * serial line. The 'tty_num' argument is 0 for /dev/ttya and 1
+ * for /dev/ttyb which is determined in setup_arch() from the
+ * boot command line flags.
+ */
+struct dec_serial_hook zs_kgdbhook = {
+ .init_channel = kgdbhook_init_channel,
+ .init_info = kgdbhook_init_info,
+ .rx_char = kgdbhook_rx_char,
+ .cflags = B38400 | CS8 | CLOCAL,
+}
+
+void __init zs_kgdb_hook(int tty_num)
+{
+ /* Find out how many Z8530 SCCs we have */
+ if (zs_chain == 0)
+ probe_sccs();
+ zs_soft[tty_num].zs_channel = &zs_channels[tty_num];
+ zs_kgdbchan = zs_soft[tty_num].zs_channel;
+ zs_soft[tty_num].change_needed = 0;
+ zs_soft[tty_num].clk_divisor = 16;
+ zs_soft[tty_num].zs_baud = 38400;
+ zs_soft[tty_num].hook = &zs_kgdbhook; /* This runs kgdb */
+ /* Turn on transmitter/receiver at 8-bits/char */
+ kgdb_chaninit(zs_soft[tty_num].zs_channel, 1, 38400);
+ printk("KGDB: on channel %d initialized\n", tty_num);
+ set_debug_traps(); /* init stub */
+}
+#endif /* ifdef CONFIG_KGDB */
+
+