patch-2.3.9 linux/drivers/tc/zs.c
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- Lines: 2108
- Date:
Fri Jun 25 17:38:40 1999
- Orig file:
v2.3.8/linux/drivers/tc/zs.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.3.8/linux/drivers/tc/zs.c linux/drivers/tc/zs.c
@@ -0,0 +1,2107 @@
+/*
+ * decserial.c: Serial port driver for IOASIC DECsatations.
+ *
+ * Derived from drivers/macintosh/macserial.c by Harald Koerfgen.
+ * Derived from drivers/sbus/char/sunserial.c by Paul Mackerras.
+ *
+ * DECstation changes
+ * Copyright (C) 1998 Harald Koerfgen (Harald.Koerfgen@home.ivm.de)
+ *
+ * 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)
+ *
+ * Keyboard and mouse are not supported right now. If you want to change this,
+ * you might want to have a look at drivers/sbus/char/sunserial.c to see
+ * how this might be done. HK
+ */
+
+#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>
+#ifdef CONFIG_SERIAL_CONSOLE
+#include <linux/console.h>
+#endif
+
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/system.h>
+#include <asm/segment.h>
+#include <asm/bitops.h>
+#include <asm/uaccess.h>
+#include <asm/dec/interrupts.h>
+#include <asm/dec/machtype.h>
+#include <asm/dec/tc.h>
+#include <asm/dec/ioasic_addrs.h>
+#ifdef CONFIG_KGDB
+#include <asm/kgdb.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 RECOVERY_DELAY udelay(2)
+
+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_CONSOLE
+static struct console sercons;
+#endif
+
+#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)*/
+};
+#endif
+
+static unsigned char zs_init_regs[16] __initdata = {
+ 0, /* write 0 */
+ 0, /* write 1 */
+ 0xf0, /* write 2 */
+ (Rx8), /* write 3 */
+ (X16CLK | SB1), /* write 4 */
+ (Tx8), /* write 5 */
+ 0, 0, 0, /* write 6, 7, 8 */
+ (VIS), /* write 9 */
+ (NRZ), /* write 10 */
+ (TCBR | RCBR), /* write 11 */
+ 0, 0, /* BRG time constant, write 12 + 13 */
+ (BRSRC | BRENABL), /* write 14 */
+ 0 /* write 15 */
+};
+
+#define ZS_CLOCK 7372800 /* Z8530 RTxC input clock rate */
+
+DECLARE_TASK_QUEUE(tq_zs_serial);
+
+struct tty_driver serial_driver, callout_driver;
+static int serial_refcount;
+
+/* serial subtype definitions */
+#define SERIAL_TYPE_NORMAL 1
+#define SERIAL_TYPE_CALLOUT 2
+
+/* number of characters left in xmit buffer before we ask for more */
+#define WAKEUP_CHARS 256
+
+/*
+ * Debugging.
+ */
+#undef SERIAL_DEBUG_INTR
+#undef SERIAL_DEBUG_OPEN
+#undef SERIAL_DEBUG_FLOW
+#undef SERIAL_DEBUG_THROTTLE
+#undef SERIAL_PARANOIA_CHECK
+
+#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);
+
+static struct tty_struct *serial_table[NUM_CHANNELS];
+static struct termios *serial_termios[NUM_CHANNELS];
+static struct termios *serial_termios_locked[NUM_CHANNELS];
+
+#ifndef MIN
+#define MIN(a,b) ((a) < (b) ? (a) : (b))
+#endif
+
+/*
+ * 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 struct semaphore tmp_buf_sem = MUTEX;
+
+static inline int serial_paranoia_check(struct dec_serial *info,
+ dev_t device, const char *routine)
+{
+#ifdef SERIAL_PARANOIA_CHECK
+ static const char *badmagic =
+ "Warning: bad magic number for serial struct (%d, %d) in %s\n";
+ static const char *badinfo =
+ "Warning: null mac_serial for (%d, %d) in %s\n";
+
+ if (!info) {
+ printk(badinfo, MAJOR(device), MINOR(device), routine);
+ return 1;
+ }
+ if (info->magic != SERIAL_MAGIC) {
+ printk(badmagic, MAJOR(device), MINOR(device), 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, 0, 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;
+ 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;
+ RECOVERY_DELAY;
+ }
+ *channel->control = value;
+ 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;
+ 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, R4, regs[R4]);
+ write_zsreg(channel, R3, regs[R3] & ~RxENABLE);
+ write_zsreg(channel, R5, regs[R5] & ~TxENAB);
+ 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 *ss, int set)
+{
+ if (ss->zs_channel != ss->zs_chan_a) {
+ if (set)
+ ss->zs_chan_a->curregs[5] |= (RTS | DTR);
+ else
+ ss->zs_chan_a->curregs[5] &= ~(RTS | DTR);
+ write_zsreg(ss->zs_chan_a, 5, ss->zs_chan_a->curregs[5]);
+ }
+ return;
+}
+
+/* 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_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, 0) & Rx_CH_AV) != 0) {
+
+ stat = read_zsreg(info->zs_channel, R1);
+ ch = read_zsdata(info->zs_channel);
+
+#ifdef CONFIG_KGDB
+ if (info->kgdb_channel) {
+ if (ch == 0x03 || ch == '$')
+ breakpoint();
+ if (stat & (Rx_OVR|FRM_ERR|PAR_ERR))
+ write_zsreg(info->zs_channel, 0, ERR_RES);
+ return;
+ }
+#endif
+ if (!tty)
+ continue;
+
+ if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
+ static int flip_buf_ovf;
+ ++flip_buf_ovf;
+ continue;
+ }
+ tty->flip.count++;
+ {
+ static int flip_max_cnt;
+ if (flip_max_cnt < tty->flip.count)
+ flip_max_cnt = tty->flip.count;
+ }
+ if (stat & Rx_OVR) {
+ flag = TTY_OVERRUN;
+ } else if (stat & FRM_ERR) {
+ flag = TTY_FRAME;
+ } else if (stat & PAR_ERR) {
+ flag = TTY_PARITY;
+ } else
+ flag = 0;
+ if (flag)
+ /* reset the error indication */
+ write_zsreg(info->zs_channel, 0, ERR_RES);
+ *tty->flip.flag_buf_ptr++ = flag;
+ *tty->flip.char_buf_ptr++ = ch;
+ }
+ tty_flip_buffer_push(tty);
+}
+
+static void transmit_chars(struct dec_serial *info)
+{
+ if ((read_zsreg(info->zs_channel, 0) & 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->stopped || info->tx_stopped) {
+ write_zsreg(info->zs_channel, 0, 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 status;
+
+ /* Get status from Read Register 0 */
+ status = read_zsreg(info->zs_channel, 0);
+
+ /* FIXEM: Check for DCD transitions */
+ if (((status ^ info->read_reg_zero) & DCD) != 0
+ && info->tty && !C_CLOCAL(info->tty)) {
+ if (status & DCD) {
+ wake_up_interruptible(&info->open_wait);
+ } else if (!(info->flags & ZILOG_CALLOUT_ACTIVE)) {
+ if (info->tty)
+ tty_hangup(info->tty);
+ }
+ }
+
+ /* Check for CTS transitions */
+ if (info->tty && C_CRTSCTS(info->tty)) {
+ /*
+ * For some reason, on the Power Macintosh,
+ * it seems that the CTS bit is 1 when CTS is
+ * *negated* and 0 when it is asserted.
+ * The DCD bit doesn't seem to be inverted
+ * like this.
+ */
+ if ((status & 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, 0, RES_EXT_INT);
+ info->read_reg_zero = status;
+}
+
+/*
+ * 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, 3) >> 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);
+ }
+ }
+}
+
+/*
+ * -------------------------------------------------------------------
+ * 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->device, "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->device, "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)) {
+ if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
+ tty->ldisc.write_wakeup)
+ (tty->ldisc.write_wakeup)(tty);
+ wake_up_interruptible(&tty->write_wait);
+ }
+}
+
+static void rs_timer(void)
+{
+}
+
+static int 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_free_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, 0, ERR_RES);
+ write_zsreg(info->zs_channel, 0, RES_H_IUS);
+
+ /*
+ * Turn on RTS and DTR.
+ */
+ zs_rtsdtr(info, 1);
+
+ /*
+ * Finally, enable sequencing and interrupts
+ */
+ info->zs_channel->curregs[1] = (info->zs_channel->curregs[1] & ~0x18) | (EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB);
+ info->zs_channel->curregs[3] |= (RxENABLE | Rx8);
+ info->zs_channel->curregs[5] |= (TxENAB | Tx8);
+ info->zs_channel->curregs[15] |= (DCDIE | CTSIE | TxUIE | BRKIE);
+ info->zs_channel->curregs[9] |= (VIS | MIE);
+ write_zsreg(info->zs_channel, 1, info->zs_channel->curregs[1]);
+ write_zsreg(info->zs_channel, 3, info->zs_channel->curregs[3]);
+ write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
+ write_zsreg(info->zs_channel, 15, info->zs_channel->curregs[15]);
+ write_zsreg(info->zs_channel, 9, info->zs_channel->curregs[9]);
+
+ /*
+ * And clear the interrupt registers again for luck.
+ */
+ write_zsreg(info->zs_channel, 0, ERR_RES);
+ write_zsreg(info->zs_channel, 0, RES_H_IUS);
+
+ if (info->tty)
+ clear_bit(TTY_IO_ERROR, &info->tty->flags);
+ info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+
+ /*
+ * Set the speed of the serial port
+ */
+ change_speed(info);
+
+ /* Save the current value of RR0 */
+ info->read_reg_zero = read_zsreg(info->zs_channel, 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)) {
+ info->zs_chan_a->curregs[5] &= ~(DTR | RTS);
+ write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
+ }
+
+ 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 short port;
+ unsigned cflag;
+ int i;
+ int brg;
+ unsigned long flags;
+
+ if (!info->tty || !info->tty->termios)
+ return;
+ cflag = info->tty->termios->c_cflag;
+ if (!(port = info->port))
+ return;
+ i = cflag & CBAUD;
+
+ save_flags(flags); cli();
+ info->zs_baud = baud_table[i];
+ info->clk_divisor = 16;
+
+ switch (info->zs_baud) {
+ default:
+ info->zs_channel->curregs[4] = X16CLK;
+ brg = BPS_TO_BRG(info->zs_baud, ZS_CLOCK/info->clk_divisor);
+ info->zs_channel->curregs[12] = (brg & 255);
+ info->zs_channel->curregs[13] = ((brg >> 8) & 255);
+ }
+
+ /* byte size and parity */
+ info->zs_channel->curregs[3] &= ~RxNBITS_MASK;
+ info->zs_channel->curregs[5] &= ~TxNBITS_MASK;
+ switch (cflag & CSIZE) {
+ case CS5:
+ info->zs_channel->curregs[3] |= Rx5;
+ info->zs_channel->curregs[5] |= Tx5;
+ break;
+ case CS6:
+ info->zs_channel->curregs[3] |= Rx6;
+ info->zs_channel->curregs[5] |= Tx6;
+ break;
+ case CS7:
+ info->zs_channel->curregs[3] |= Rx7;
+ info->zs_channel->curregs[5] |= Tx7;
+ break;
+ case CS8:
+ default: /* defaults to 8 bits */
+ info->zs_channel->curregs[3] |= Rx8;
+ info->zs_channel->curregs[5] |= Tx8;
+ break;
+ }
+
+ 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->device, "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, int from_user,
+ 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->device, "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->device, "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->device, "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->device, "rs_flush_buffer"))
+ return;
+ cli();
+ info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+ sti();
+ wake_up_interruptible(&tty->write_wait);
+ if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
+ tty->ldisc.write_wakeup)
+ (tty->ldisc.write_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->device, "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)) {
+ /*
+ * Here we want to turn off the RTS line. On Macintoshes,
+ * we only get the DTR line, which goes to both DTR and
+ * RTS on the modem. RTS doesn't go out to the serial
+ * port socket. So you should make sure your modem is
+ * set to ignore DTR if you're using CRTSCTS.
+ */
+ save_flags(flags); cli();
+ info->zs_chan_a->curregs[5] &= ~(DTR | RTS);
+ write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
+ restore_flags(flags);
+ }
+}
+
+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->device, "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)) {
+ /* Assert RTS and DTR lines */
+ save_flags(flags); cli();
+ info->zs_chan_a->curregs[5] |= DTR | RTS;
+ write_zsreg(info->zs_chan_a, 5, info->zs_chan_a->curregs[5]);
+ restore_flags(flags);
+ }
+}
+
+/*
+ * ------------------------------------------------------------
+ * 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));
+}
+
+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 (!suser()) {
+ 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 = 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 get_modem_info(struct dec_serial *info, unsigned int *value)
+{
+ unsigned char control, status;
+ unsigned int result;
+
+ cli();
+ control = info->zs_chan_a->curregs[5];
+ status = read_zsreg(info->zs_channel, 0);
+ sti();
+ result = ((control & RTS) ? TIOCM_RTS: 0)
+ | ((control & DTR) ? TIOCM_DTR: 0)
+ | ((status & DCD) ? TIOCM_CAR: 0)
+ | ((status & CTS) ? 0: TIOCM_CTS);
+ put_user(result,value);
+ return 0;
+}
+
+static int set_modem_info(struct dec_serial *info, unsigned int cmd,
+ unsigned int *value)
+{
+ int error;
+ unsigned int arg, bits;
+
+ error = verify_area(VERIFY_READ, value, sizeof(int));
+ if (error)
+ return error;
+ get_user(arg, value);
+ bits = (arg & TIOCM_RTS? RTS: 0) + (arg & TIOCM_DTR? DTR: 0);
+ cli();
+ switch (cmd) {
+ case TIOCMBIS:
+ info->zs_chan_a->curregs[5] |= bits;
+ break;
+ case TIOCMBIC:
+ info->zs_chan_a->curregs[5] &= ~bits;
+ break;
+ case TIOCMSET:
+ info->zs_chan_a->curregs[5] = (info->zs_chan_a->curregs[5] & ~(DTR | RTS)) | bits;
+ break;
+ default:
+ sti();
+ return -EINVAL;
+ }
+ 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->device, "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;
+
+#ifdef CONFIG_KGDB
+ if (info->kgdb_channel)
+ return -ENODEV;
+#endif
+ if (serial_paranoia_check(info, tty->device, "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 TIOCMGET:
+ error = verify_area(VERIFY_WRITE, (void *) arg,
+ sizeof(unsigned int));
+ if (error)
+ return error;
+ 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:
+ error = verify_area(VERIFY_WRITE, (void *) arg,
+ sizeof(struct serial_struct));
+ if (error)
+ return error;
+ 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 */
+ error = verify_area(VERIFY_WRITE, (void *) arg,
+ sizeof(unsigned int));
+ if (error)
+ return error;
+ else
+ return get_lsr_info(info, (unsigned int *) arg);
+
+ case TIOCSERGSTRUCT:
+ error = verify_area(VERIFY_WRITE, (void *) arg,
+ sizeof(struct dec_serial));
+ if (error)
+ return error;
+ 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->device, "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;
+ /*
+ * Save the termios structure, since this port may have
+ * separate termios for callout and dialin.
+ */
+ if (info->flags & ZILOG_NORMAL_ACTIVE)
+ info->normal_termios = *tty->termios;
+ if (info->flags & ZILOG_CALLOUT_ACTIVE)
+ info->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->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);
+ if (tty->ldisc.flush_buffer)
+ tty->ldisc.flush_buffer(tty);
+ tty->closing = 0;
+ info->event = 0;
+ info->tty = 0;
+ if (info->blocked_open) {
+ if (info->close_delay) {
+ current->state = TASK_INTERRUPTIBLE;
+ schedule_timeout(info->close_delay);
+ }
+ wake_up_interruptible(&info->open_wait);
+ }
+ info->flags &= ~(ZILOG_NORMAL_ACTIVE|ZILOG_CALLOUT_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, char_time;
+
+ if (serial_paranoia_check(info, tty->device, "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) & ALL_SNT) == 0) {
+ current->state = TASK_INTERRUPTIBLE;
+ current->counter = 0; /* make us low-priority */
+ schedule_timeout(char_time);
+ if (signal_pending(current))
+ break;
+ if (timeout && ((orig_jiffies + timeout) < jiffies))
+ 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->device, "rs_hangup"))
+ return;
+
+ rs_flush_buffer(tty);
+ shutdown(info);
+ info->event = 0;
+ info->count = 0;
+ info->flags &= ~(ZILOG_NORMAL_ACTIVE|ZILOG_CALLOUT_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)
+{
+ struct wait_queue wait = { current, NULL };
+ 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 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 & ZILOG_NORMAL_ACTIVE)
+ return -EBUSY;
+ if ((info->flags & ZILOG_CALLOUT_ACTIVE) &&
+ (info->flags & ZILOG_SESSION_LOCKOUT) &&
+ (info->session != current->session))
+ return -EBUSY;
+ if ((info->flags & ZILOG_CALLOUT_ACTIVE) &&
+ (info->flags & ZILOG_PGRP_LOCKOUT) &&
+ (info->pgrp != current->pgrp))
+ return -EBUSY;
+ info->flags |= ZILOG_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 & ZILOG_CALLOUT_ACTIVE)
+ return -EBUSY;
+ info->flags |= ZILOG_NORMAL_ACTIVE;
+ return 0;
+ }
+
+ if (info->flags & ZILOG_CALLOUT_ACTIVE) {
+ if (info->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, 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 (!(info->flags & ZILOG_CALLOUT_ACTIVE) &&
+ (tty->termios->c_cflag & CBAUD))
+ zs_rtsdtr(info, 1);
+ sti();
+ 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_CALLOUT_ACTIVE) &&
+ !(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 = MINOR(tty->device) - tty->driver.minor_start;
+ if ((line < 0) || (line >= zs_channels_found))
+ return -ENODEV;
+ info = zs_soft + line;
+
+#ifdef CONFIG_KGDB
+ if (info->kgdb_channel)
+ return -ENODEV;
+#endif
+ if (serial_paranoia_check(info, tty->device, "rs_open"))
+ return -ENODEV;
+#ifdef SERIAL_DEBUG_OPEN
+ printk("rs_open %s%d, count = %d\n", tty->driver.name, info->line,
+ 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 = 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;
+ }
+
+ if ((info->count == 1) && (info->flags & ZILOG_SPLIT_TERMIOS)) {
+ if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
+ *tty->termios = info->normal_termios;
+ else
+ *tty->termios = info->callout_termios;
+ change_speed(info);
+ }
+#ifdef CONFIG_SERIAL_CONSOLE
+ if (sercons.cflag && sercons.index == line) {
+ tty->termios->c_cflag = sercons.cflag;
+ sercons.cflag = 0;
+ change_speed(info);
+ }
+#endif
+
+ info->session = current->session;
+ info->pgrp = current->pgrp;
+
+#ifdef SERIAL_DEBUG_OPEN
+ printk("rs_open ttys%d successful...", info->line);
+#endif
+/* tty->low_latency = 1; */
+ return 0;
+}
+
+/* Finally, routines used to initialize the serial driver. */
+
+__initfunc(static void show_serial_version(void))
+{
+ printk("DECstation Z8530 serial driver version 0.03\n");
+}
+
+/* Initialize Z8530s zs_channels
+ */
+
+__initfunc(static void 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(!IOASIC) {
+ 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) {
+ case MACH_DS5000_2X0:
+ system_base = 0xbf800000;
+ n_chips = 2;
+ break;
+ case MACH_DS5000_1XX:
+ system_base = 0xbc000000;
+ n_chips = 2;
+ break;
+ case MACH_DS5000_XX:
+ system_base = 0xbc000000;
+ n_chips = 1;
+ break;
+ }
+
+ 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 ? SCC0 : SCC1) + (0 == channel ? 1 : 9);
+ zs_channels[n_channels].data = zs_channels[n_channels].control + 4;
+ zs_soft[n_channels].zs_channel = &zs_channels[n_channels];
+ zs_soft[n_channels].irq = SERIAL;
+
+ if (0 == channel)
+ zs_soft[n_channels].zs_chan_a = &zs_channels[n_channels+1];
+ 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 (((int)zs_channels[n].control & 0xf) == 1) {
+ write_zsreg(zs_soft[channel].zs_chan_a, R9, FHWRES);
+ udelay(10000);
+ write_zsreg(zs_soft[channel].zs_chan_a, R9, 0);
+ }
+ load_zsregs(zs_soft[n].zs_channel, zs_soft[n].zs_channel->curregs);
+ }
+ restore_flags(flags); */
+}
+
+/* zs_init inits the driver */
+__initfunc(int zs_init(void))
+{
+ int channel, i;
+ unsigned long flags;
+ struct dec_serial *info;
+
+ if(!IOASIC)
+ return -ENODEV;
+
+ /* Setup base handler, and timer table. */
+ init_bh(SERIAL_BH, do_serial_bh);
+ timer_table[RS_TIMER].fn = rs_timer;
+ timer_table[RS_TIMER].expires = 0;
+
+ /* Find out how many Z8530 SCCs we have */
+ if (zs_chain == 0)
+ probe_sccs();
+
+ show_serial_version();
+
+ /* Initialize the tty_driver structure */
+ /* Not all of this is exactly right for us. */
+
+ memset(&serial_driver, 0, sizeof(struct tty_driver));
+ serial_driver.magic = TTY_DRIVER_MAGIC;
+ serial_driver.name = "ttyS";
+ serial_driver.major = TTY_MAJOR;
+ serial_driver.minor_start = 64;
+ serial_driver.num = zs_channels_found;
+ 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;
+ serial_driver.refcount = &serial_refcount;
+ serial_driver.table = serial_table;
+ serial_driver.termios = serial_termios;
+ serial_driver.termios_locked = serial_termios_locked;
+
+ serial_driver.open = rs_open;
+ serial_driver.close = rs_close;
+ serial_driver.write = rs_write;
+ serial_driver.flush_chars = rs_flush_chars;
+ serial_driver.write_room = rs_write_room;
+ serial_driver.chars_in_buffer = rs_chars_in_buffer;
+ serial_driver.flush_buffer = rs_flush_buffer;
+ serial_driver.ioctl = rs_ioctl;
+ serial_driver.throttle = rs_throttle;
+ serial_driver.unthrottle = rs_unthrottle;
+ serial_driver.set_termios = rs_set_termios;
+ serial_driver.stop = rs_stop;
+ serial_driver.start = rs_start;
+ serial_driver.hangup = rs_hangup;
+ serial_driver.break_ctl = rs_break;
+ serial_driver.wait_until_sent = rs_wait_until_sent;
+
+ /*
+ * The callout device is just like normal device except for
+ * major number and the subtype code.
+ */
+ callout_driver = serial_driver;
+ callout_driver.name = "cua";
+ callout_driver.major = TTYAUX_MAJOR;
+ callout_driver.subtype = SERIAL_TYPE_CALLOUT;
+
+ if (tty_register_driver(&serial_driver))
+ panic("Couldn't register serial driver\n");
+ if (tty_register_driver(&callout_driver))
+ panic("Couldn't register callout driver\n");
+
+ save_flags(flags); cli();
+
+ for (channel = 0; channel < zs_channels_found; ++channel) {
+#ifdef CONFIG_KGDB
+ if (zs_soft[channel].kgdb_channel) {
+ continue;
+ }
+#endif
+ zs_soft[channel].clk_divisor = 16;
+ zs_soft[channel].zs_baud = get_zsbaud(&zs_soft[channel]);
+
+ if (request_irq(SERIAL, rs_interrupt, SA_SHIRQ,
+ "SCC", &zs_soft[channel]))
+ printk(KERN_ERR "decserial: can't get irq %d\n",
+ SERIAL);
+
+ /* If console serial line, then enable interrupts. */
+/* if (zs_soft[channel].is_cons) {
+ write_zsreg(zs_soft[channel].zs_channel, R1,
+ (EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB));
+ write_zsreg(zs_soft[channel].zs_channel, R9,
+ (VIS | MIE));
+ }
+*/
+ }
+
+ for (info = zs_chain, i = 0; info; info = info->zs_next, i++)
+ {
+#ifdef CONFIG_KGDB
+ if (info->kgdb_channel) {
+ continue;
+ }
+#endif
+ info->magic = SERIAL_MAGIC;
+ info->port = (int) info->zs_channel->control;
+ info->line = i;
+ info->tty = 0;
+ info->custom_divisor = 16;
+ info->close_delay = 50;
+ info->closing_wait = 3000;
+ info->x_char = 0;
+ info->event = 0;
+ info->count = 0;
+ info->blocked_open = 0;
+ info->tqueue.routine = do_softint;
+ info->tqueue.data = info;
+ info->callout_termios =callout_driver.init_termios;
+ info->normal_termios = serial_driver.init_termios;
+ info->open_wait = 0;
+ info->close_wait = 0;
+ printk("tty%02d at 0x%08x (irq = %d)", info->line,
+ info->port, info->irq);
+ printk(" is a Z85C30 SCC\n");
+ }
+
+ restore_flags(flags);
+
+ return 0;
+}
+
+/*
+ * register_serial and unregister_serial allows for serial ports to be
+ * configured at run-time, to support PCMCIA modems.
+ */
+/* PowerMac: Unused at this time, just here to make things link. */
+int register_serial(struct serial_struct *req)
+{
+ return -1;
+}
+
+void unregister_serial(int line)
+{
+ return;
+}
+
+/*
+ * ------------------------------------------------------------
+ * Serial console driver
+ * ------------------------------------------------------------
+ */
+#ifdef CONFIG_SERIAL_CONSOLE
+
+
+/*
+ * Print a string to the serial port trying not to disturb
+ * any possible real use of the port...
+ */
+
+/* This is for console output */
+static void
+zs_console_putchar(struct dec_serial *info, char ch)
+{
+ int loops = 10000;
+ unsigned long flags;
+
+ if(!info->zs_channel)
+ return;
+
+ save_flags(flags); cli();
+
+ while (!(*(info->zs_channel->control) & Tx_BUF_EMP) && --loops)
+ RECOVERY_DELAY;
+ *(info->zs_channel->data) = ch;
+ RECOVERY_DELAY;
+
+ restore_flags(flags);
+}
+
+static void serial_console_write(struct console *co, const char *s,
+ unsigned count)
+{
+ struct dec_serial *info;
+ int i;
+ unsigned char nine;
+
+ info = zs_soft + co->index;
+
+#if 0
+ /*
+ * disable master interrupt if necessary
+ */
+ nine = info->zs_channel->curregs[9];
+ if(nine & MIE)
+ write_zsreg(info->zs_channel, R9, nine & ~MIE);
+#endif
+ /*
+ * do it
+ */
+ for (i = 0; i < count; i++, s++) {
+ if(*s == '\n')
+ zs_console_putchar(info, '\r');
+ zs_console_putchar(info, *s);
+ }
+ /*
+ * restore master interrupt enable
+ */
+#if 0
+ write_zsreg(info->zs_channel, R9, nine);
+#endif
+}
+
+/*
+ * Receive character from the serial port
+ */
+static int serial_console_wait_key(struct console *co)
+{
+ return 0;
+}
+
+static kdev_t serial_console_device(struct console *c)
+{
+ return MKDEV(TTY_MAJOR, 64 + c->index);
+}
+
+/*
+ * 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.
+ */
+__initfunc(static int 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;
+ char *s;
+ unsigned long flags;
+
+ if(!IOASIC)
+ 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;
+ 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;
+#if 1
+ save_and_cli(flags);
+
+ /*
+ * Turn on RTS and DTR.
+ */
+ zs_rtsdtr(info, 1);
+
+ /*
+ * Finally, enable sequencing
+ */
+ info->zs_channel->curregs[3] |= (RxENABLE | Rx8);
+ info->zs_channel->curregs[5] |= (TxENAB | Tx8);
+ info->zs_channel->curregs[9] |= (VIS);
+ write_zsreg(info->zs_channel, 3, info->zs_channel->curregs[3]);
+ write_zsreg(info->zs_channel, 5, info->zs_channel->curregs[5]);
+ write_zsreg(info->zs_channel, 9, info->zs_channel->curregs[9]);
+
+ /*
+ * Clear the interrupt registers.
+ */
+ write_zsreg(info->zs_channel, 0, ERR_RES);
+ write_zsreg(info->zs_channel, 0, RES_H_IUS);
+
+ /*
+ * Set the speed of the serial port
+ */
+ change_speed(info);
+
+ /* Save the current value of RR0 */
+ info->read_reg_zero = read_zsreg(info->zs_channel, 0);
+
+ zs_soft[co->index].clk_divisor = 16;
+ zs_soft[co->index].zs_baud = get_zsbaud(&zs_soft[co->index]);
+
+ restore_flags(flags);
+#endif
+ return 0;
+}
+
+static struct console sercons = {
+ "ttyS",
+ serial_console_write,
+ NULL,
+ serial_console_device,
+ serial_console_wait_key,
+ NULL,
+ serial_console_setup,
+ CON_PRINTBUFFER,
+ -1,
+ 0,
+ NULL
+};
+
+/*
+ * Register console.
+ */
+__initfunc (long zs_serial_console_init(long kmem_start, long kmem_end))
+{
+ register_console(&sercons);
+ return kmem_start;
+}
+#endif /* ifdef CONFIG_SERIAL_CONSOLE */
+
+#ifdef CONFIG_KGDB
+/* 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|INT_ALL_Rx;
+ 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);
+}
+/* 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_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.
+ */
+__initfunc(void 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].kgdb_channel = 1; /* This runs kgdb */
+ zs_soft[tty_num ^ 1].kgdb_channel = 0; /* This does not */
+ /* 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 */
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)