/* * generic_serial.c * * Copyright (C) 1998/1999 R.E.Wolff@BitWizard.nl * * written for the SX serial driver. * Contains the code that should be shared over all the serial drivers. * * Credit for the idea to do it this way might go to Alan Cox. * * * Version 0.1 -- December, 1998. Initial version. * Version 0.2 -- March, 1999. Some more routines. Bugfixes. Etc. * Version 0.5 -- August, 1999. Some more fixes. Reformat for Linus. */ #include #include #include #include #include #include #include #include #define DEBUG static char * tmp_buf; static DECLARE_MUTEX(tmp_buf_sem); int gs_debug = 0; #ifdef DEBUG #define gs_dprintk(f, str...) if (gs_debug & f) printk (str) #else #define gs_dprintk(f, str...) /* nothing */ #endif #define func_enter() gs_dprintk (GS_DEBUG_FLOW, "gs: enter " __FUNCTION__ "\n") #define func_exit() gs_dprintk (GS_DEBUG_FLOW, "gs: exit " __FUNCTION__ "\n") #if NEW_WRITE_LOCKING #define DECL /* Nothing */ #define LOCKIT down (& port->port_write_sem); #define RELEASEIT up (&port->port_write_sem); #else #define DECL unsigned long flags; #define LOCKIT save_flags (flags);cli () #define RELEASEIT restore_flags (flags) #endif #define RS_EVENT_WRITE_WAKEUP 1 #ifdef MODULE MODULE_PARM(gs_debug, "i"); #endif #ifdef DEBUG static void my_hd (unsigned char *addr, int len) { int i, j, ch; for (i=0;i 0x7f)?'.':ch)); } printk ("\n"); } } #else #define my_hd(addr,len) #endif void gs_put_char(struct tty_struct * tty, unsigned char ch) { struct gs_port *port = tty->driver_data; DECL /* func_enter (); */ /* Take a lock on the serial tranmit buffer! */ LOCKIT; if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) { /* Sorry, buffer is full, drop character. Update statistics???? -- REW */ RELEASEIT; return; } port->xmit_buf[port->xmit_head++] = ch; port->xmit_head &= SERIAL_XMIT_SIZE - 1; port->xmit_cnt++; /* Characters in buffer */ RELEASEIT; /* func_exit ();*/ } #ifdef NEW_WRITE_LOCKING /* > Problems to take into account are: > -1- Interrupts that empty part of the buffer. > -2- page faults on the access to userspace. > -3- Other processes that are also trying to do a "write". */ int gs_write(struct tty_struct * tty, int from_user, const unsigned char *buf, int count) { struct gs_port *port = tty->driver_data; int c, total = 0; int t; /* func_enter (); */ if (! (port->flags & ASYNC_INITIALIZED)) return 0; /* get exclusive "write" access to this port (problem 3) */ /* This is not a spinlock because we can have a disk access (page fault) in copy_from_user */ down (& port->port_write_sem); while (1) { c = count; /* This is safe because we "OWN" the "head". Noone else can change the "head": we own the port_write_sem. */ /* Don't overrun the end of the buffer */ t = SERIAL_XMIT_SIZE - port->xmit_head; if (t < c) c = t; /* This is safe because the xmit_cnt can only decrease. This would increase "t", so we might copy too little chars. */ /* Don't copy past the "head" of the buffer */ t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt; if (t < c) c = t; /* Can't copy more? break out! */ if (c <= 0) break; if (from_user) copy_from_user (port->xmit_buf + port->xmit_head, buf, c); else memcpy (port->xmit_buf + port->xmit_head, buf, c); port -> xmit_cnt += c; port -> xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE -1); buf += c; count -= c; total += c; } up (& port->port_write_sem); gs_dprintk (GS_DEBUG_WRITE, "write: interrupts are %s\n", (port->flags & GS_TX_INTEN)?"enabled": "disabled"); if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped && !(port->flags & GS_TX_INTEN)) { port->flags |= GS_TX_INTEN; port->rd->enable_tx_interrupts (port); } /* func_exit (); */ return total; } #else /* > Problems to take into account are: > -1- Interrupts that empty part of the buffer. > -2- page faults on the access to userspace. > -3- Other processes that are also trying to do a "write". */ int gs_write(struct tty_struct * tty, int from_user, const unsigned char *buf, int count) { struct gs_port *port; int c, total = 0; int t; unsigned long flags; func_enter (); /* The standard serial driver returns 0 in this case. That sounds to me as "No error, I just didn't get to writing any bytes. Feel free to try again." The "official" way to write n bytes from buf is: for (nwritten = 0;nwritten < n;nwritten += rv) { rv = write (fd, buf+nwritten, n-nwritten); if (rv < 0) break; // Error: bail out. // } which will loop endlessly in this case. The manual page for write agrees with me. In practise almost everybody writes "write (fd, buf,n);" but some people might have had to deal with incomplete writes in the past and correctly implemented it by now... */ if (!tty) return -EIO; port = tty->driver_data; if (!port || !port->xmit_buf || !tmp_buf) return -EIO; save_flags(flags); if (from_user) { down(&tmp_buf_sem); while (1) { c = count; /* This is safe because we "OWN" the "head". Noone else can change the "head": we own the port_write_sem. */ /* Don't overrun the end of the buffer */ t = SERIAL_XMIT_SIZE - port->xmit_head; if (t < c) c = t; /* This is safe because the xmit_cnt can only decrease. This would increase "t", so we might copy too little chars. */ /* Don't copy past the "head" of the buffer */ t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt; if (t < c) c = t; /* Can't copy more? break out! */ if (c <= 0) break; c -= copy_from_user(tmp_buf, buf, c); if (!c) { if (!total) total = -EFAULT; break; } cli(); t = SERIAL_XMIT_SIZE - port->xmit_head; if (t < c) c = t; t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt; if (t < c) c = t; memcpy(port->xmit_buf + port->xmit_head, tmp_buf, c); port->xmit_head = ((port->xmit_head + c) & (SERIAL_XMIT_SIZE-1)); port->xmit_cnt += c; restore_flags(flags); buf += c; count -= c; total += c; } up(&tmp_buf_sem); } else { while (1) { cli(); c = count; /* This is safe because we "OWN" the "head". Noone else can change the "head": we own the port_write_sem. */ /* Don't overrun the end of the buffer */ t = SERIAL_XMIT_SIZE - port->xmit_head; if (t < c) c = t; /* This is safe because the xmit_cnt can only decrease. This would increase "t", so we might copy too little chars. */ /* Don't copy past the "head" of the buffer */ t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt; if (t < c) c = t; /* Can't copy more? break out! */ if (c <= 0) { restore_flags(flags); break; } memcpy(port->xmit_buf + port->xmit_head, buf, c); port->xmit_head = ((port->xmit_head + c) & (SERIAL_XMIT_SIZE-1)); port->xmit_cnt += c; restore_flags(flags); buf += c; count -= c; total += c; } } if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped && !(port->flags & GS_TX_INTEN)) { port->flags |= GS_TX_INTEN; port->rd->enable_tx_interrupts (port); } func_exit (); return total; } #endif int gs_write_room(struct tty_struct * tty) { struct gs_port *port = tty->driver_data; int ret; /* func_enter (); */ ret = SERIAL_XMIT_SIZE - port->xmit_cnt - 1; if (ret < 0) ret = 0; /* func_exit (); */ return ret; } int gs_chars_in_buffer(struct tty_struct *tty) { struct gs_port *port = tty->driver_data; func_enter (); func_exit (); return port->xmit_cnt; } int gs_real_chars_in_buffer(struct tty_struct *tty) { struct gs_port *port; func_enter (); if (!tty) return 0; port = tty->driver_data; if (!port->rd) return 0; if (!port->rd->chars_in_buffer) return 0; func_exit (); return port->xmit_cnt + port->rd->chars_in_buffer (port); } static int gs_wait_tx_flushed (void * ptr, int timeout) { struct gs_port *port = ptr; long end_jiffies; int jiffies_to_transmit, charsleft = 0, rv = 0; int to, rcib; func_enter(); gs_dprintk (GS_DEBUG_FLUSH, "port=%p.\n", port); if (port) { gs_dprintk (GS_DEBUG_FLUSH, "xmit_cnt=%x, xmit_buf=%p, tty=%p.\n", port->xmit_cnt, port->xmit_buf, port->tty); } if (!port || port->xmit_cnt < 0 || !port->xmit_buf) { gs_dprintk (GS_DEBUG_FLUSH, "ERROR: !port, !port->xmit_buf or prot->xmit_cnt < 0.\n"); func_exit(); return -EINVAL; /* This is an error which we don't know how to handle. */ } rcib = gs_real_chars_in_buffer(port->tty); if(rcib <= 0) { gs_dprintk (GS_DEBUG_FLUSH, "nothing to wait for.\n"); func_exit(); return rv; } /* stop trying: now + twice the time it would normally take + seconds */ end_jiffies = jiffies; if (timeout != MAX_SCHEDULE_TIMEOUT) end_jiffies += port->baud?(2 * rcib * 10 * HZ / port->baud):0; end_jiffies += timeout; gs_dprintk (GS_DEBUG_FLUSH, "now=%lx, end=%lx (%ld).\n", jiffies, end_jiffies, end_jiffies-jiffies); to = 100; /* the expression is actually jiffies < end_jiffies, but that won't work around the wraparound. Tricky eh? */ while (to-- && (charsleft = gs_real_chars_in_buffer (port->tty)) && time_after (end_jiffies, jiffies)) { /* Units check: chars * (bits/char) * (jiffies /sec) / (bits/sec) = jiffies! check! */ charsleft += 16; /* Allow 16 chars more to be transmitted ... */ jiffies_to_transmit = port->baud?(1 + charsleft * 10 * HZ / port->baud):0; /* ^^^ Round up.... */ if (jiffies_to_transmit <= 0) jiffies_to_transmit = 1; gs_dprintk (GS_DEBUG_FLUSH, "Expect to finish in %d jiffies " "(%d chars).\n", jiffies_to_transmit, charsleft); current->state = TASK_INTERRUPTIBLE; schedule_timeout(jiffies_to_transmit); if (signal_pending (current)) { gs_dprintk (GS_DEBUG_FLUSH, "Signal pending. Bombing out: "); rv = -EINTR; break; } } gs_dprintk (GS_DEBUG_FLUSH, "charsleft = %d.\n", charsleft); current->state = TASK_RUNNING; func_exit(); return rv; } void gs_flush_buffer(struct tty_struct *tty) { struct gs_port *port = tty->driver_data; unsigned long flags; func_enter (); /* XXX Would the write semaphore do? */ save_flags(flags); cli(); port->xmit_cnt = port->xmit_head = port->xmit_tail = 0; restore_flags(flags); wake_up_interruptible(&tty->write_wait); if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup) (tty->ldisc.write_wakeup)(tty); func_exit (); } void gs_flush_chars(struct tty_struct * tty) { struct gs_port *port = tty->driver_data; func_enter (); if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped || !port->xmit_buf) { func_exit (); return; } /* Beats me -- REW */ port->flags |= GS_TX_INTEN; port->rd->enable_tx_interrupts (port); func_exit (); } void gs_stop(struct tty_struct * tty) { struct gs_port *port = tty->driver_data; func_enter (); if (port->xmit_cnt && port->xmit_buf && (port->flags & GS_TX_INTEN) ) { port->flags &= ~GS_TX_INTEN; port->rd->disable_tx_interrupts (port); } func_exit (); } void gs_start(struct tty_struct * tty) { struct gs_port *port = tty->driver_data; if (port->xmit_cnt && port->xmit_buf && !(port->flags & GS_TX_INTEN) ) { port->flags |= GS_TX_INTEN; port->rd->enable_tx_interrupts (port); } func_exit (); } void gs_shutdown_port (struct gs_port *port) { long flags; func_enter(); if (!(port->flags & ASYNC_INITIALIZED)) return; save_flags (flags); cli (); if (port->xmit_buf) { free_page((unsigned long) port->xmit_buf); port->xmit_buf = 0; } if (port->tty) set_bit(TTY_IO_ERROR, &port->tty->flags); port->rd->shutdown_port (port); port->flags &= ~ASYNC_INITIALIZED; restore_flags (flags); func_exit(); } void gs_hangup(struct tty_struct *tty) { struct gs_port *port = tty->driver_data; func_enter (); tty = port->tty; if (!tty) return; gs_shutdown_port (port); port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE |GS_ACTIVE); port->tty = NULL; port->count = 0; wake_up_interruptible(&port->open_wait); func_exit (); } void gs_do_softint(void *private_) { struct gs_port *port = private_; struct tty_struct *tty; tty = port->tty; if(!tty) return; if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &port->event)) { if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup) (tty->ldisc.write_wakeup)(tty); wake_up_interruptible(&tty->write_wait); } func_exit (); } int block_til_ready(void *port_, struct file * filp) { struct gs_port *port = port_; DECLARE_WAITQUEUE(wait, current); int retval; int do_clocal = 0; int CD; struct tty_struct *tty; func_enter (); tty = port->tty; gs_dprintk (GS_DEBUG_BTR, "Entering block_till_ready.\n"); /* * If the device is in the middle of being closed, then block * until it's done, and then try again. */ if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) { interruptible_sleep_on(&port->close_wait); if (port->flags & ASYNC_HUP_NOTIFY) return -EAGAIN; else return -ERESTARTSYS; } gs_dprintk (GS_DEBUG_BTR, "after hung up\n"); /* * If this is a callout device, then just make sure the normal * device isn't being used. */ if (tty->driver.subtype == GS_TYPE_CALLOUT) { if (port->flags & ASYNC_NORMAL_ACTIVE) return -EBUSY; if ((port->flags & ASYNC_CALLOUT_ACTIVE) && (port->flags & ASYNC_SESSION_LOCKOUT) && (port->session != current->session)) return -EBUSY; if ((port->flags & ASYNC_CALLOUT_ACTIVE) && (port->flags & ASYNC_PGRP_LOCKOUT) && (port->pgrp != current->pgrp)) return -EBUSY; port->flags |= ASYNC_CALLOUT_ACTIVE; return 0; } gs_dprintk (GS_DEBUG_BTR, "after subtype\n"); /* * 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 (port->flags & ASYNC_CALLOUT_ACTIVE) return -EBUSY; port->flags |= ASYNC_NORMAL_ACTIVE; return 0; } gs_dprintk (GS_DEBUG_BTR, "after nonblock\n"); if (port->flags & ASYNC_CALLOUT_ACTIVE) { if (port->normal_termios.c_cflag & CLOCAL) do_clocal = 1; } else { if (C_CLOCAL(tty)) do_clocal = 1; } gs_dprintk (GS_DEBUG_BTR, "after clocal check.\n"); /* * 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, port->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(&port->open_wait, &wait); gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n"); cli(); if (!tty_hung_up_p(filp)) port->count--; sti(); port->blocked_open++; while (1) { CD = port->rd->get_CD (port); gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD); set_current_state(TASK_INTERRUPTIBLE); if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) { if (port->flags & ASYNC_HUP_NOTIFY) retval = -EAGAIN; else retval = -ERESTARTSYS; break; } if (!(port->flags & ASYNC_CALLOUT_ACTIVE) && !(port->flags & ASYNC_CLOSING) && (do_clocal || CD)) break; gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n", (int)signal_pending (current), *(long*)(¤t->blocked)); if (signal_pending(current)) { retval = -ERESTARTSYS; break; } schedule(); } gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n", port->blocked_open); set_current_state (TASK_RUNNING); remove_wait_queue(&port->open_wait, &wait); if (!tty_hung_up_p(filp)) port->count++; port->blocked_open--; if (retval) return retval; port->flags |= ASYNC_NORMAL_ACTIVE; func_exit (); return 0; } void gs_close(struct tty_struct * tty, struct file * filp) { unsigned long flags; struct gs_port *port; func_enter (); port = (struct gs_port *) tty->driver_data; if(! port) { func_exit(); return; } if (!port->tty) { /* This seems to happen when this is called from vhangup. */ gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->tty is NULL\n"); port->tty = tty; } save_flags(flags); cli(); if (tty_hung_up_p(filp)) { restore_flags(flags); port->rd->hungup (port); func_exit (); return; } if ((tty->count == 1) && (port->count != 1)) { printk(KERN_ERR "gs: gs_close: bad port count;" " tty->count is 1, port count is %d\n", port->count); port->count = 1; } if (--port->count < 0) { printk(KERN_ERR "gs: gs_close: bad port count: %d\n", port->count); port->count = 0; } if (port->count) { gs_dprintk(GS_DEBUG_CLOSE, "gs_close: count: %d\n", port->count); restore_flags(flags); func_exit (); return; } port->flags |= ASYNC_CLOSING; /* * Save the termios structure, since this port may have * separate termios for callout and dialin. */ if (port->flags & ASYNC_NORMAL_ACTIVE) port->normal_termios = *tty->termios; if (port->flags & ASYNC_CALLOUT_ACTIVE) port->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 (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) tty_wait_until_sent(tty, port->closing_wait); */ /* * At this point we stop accepting input. To do this, we * disable the receive line status interrupts, and tell the * interrupt driver to stop checking the data ready bit in the * line status register. */ port->rd->disable_rx_interrupts (port); /* close has no way of returning "EINTR", so discard return value */ if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) gs_wait_tx_flushed (port, port->closing_wait); port->flags &= ~GS_ACTIVE; if (tty->driver.flush_buffer) tty->driver.flush_buffer(tty); if (tty->ldisc.flush_buffer) tty->ldisc.flush_buffer(tty); tty->closing = 0; port->event = 0; port->rd->close (port); port->rd->shutdown_port (port); port->tty = 0; if (port->blocked_open) { if (port->close_delay) { current->state = TASK_INTERRUPTIBLE; schedule_timeout(port->close_delay); } wake_up_interruptible(&port->open_wait); } port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE| ASYNC_CLOSING | ASYNC_INITIALIZED); wake_up_interruptible(&port->close_wait); restore_flags(flags); func_exit (); } static unsigned int gs_baudrates[] = { 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600 }; void gs_set_termios (struct tty_struct * tty, struct termios * old_termios) { struct gs_port *port = tty->driver_data; int baudrate, tmp, rv; struct termios *tiosp; func_enter(); tiosp = tty->termios; if (gs_debug & GS_DEBUG_TERMIOS) { gs_dprintk (GS_DEBUG_TERMIOS, "termios structure (%p):\n", tiosp); } #if 0 /* This is an optimization that is only allowed for dumb cards */ /* Smart cards require knowledge of iflags and oflags too: that might change hardware cooking mode.... */ #endif if (old_termios) { if( (tiosp->c_iflag == old_termios->c_iflag) && (tiosp->c_oflag == old_termios->c_oflag) && (tiosp->c_cflag == old_termios->c_cflag) && (tiosp->c_lflag == old_termios->c_lflag) && (tiosp->c_line == old_termios->c_line) && (memcmp(tiosp->c_cc, old_termios->c_cc, NCC) == 0)) { gs_dprintk(GS_DEBUG_TERMIOS, "gs_set_termios: optimized away\n"); return /* 0 */; } } else gs_dprintk(GS_DEBUG_TERMIOS, "gs_set_termios: no old_termios: " "no optimization\n"); if(old_termios && (gs_debug & GS_DEBUG_TERMIOS)) { if(tiosp->c_iflag != old_termios->c_iflag) printk("c_iflag changed\n"); if(tiosp->c_oflag != old_termios->c_oflag) printk("c_oflag changed\n"); if(tiosp->c_cflag != old_termios->c_cflag) printk("c_cflag changed\n"); if(tiosp->c_lflag != old_termios->c_lflag) printk("c_lflag changed\n"); if(tiosp->c_line != old_termios->c_line) printk("c_line changed\n"); if(!memcmp(tiosp->c_cc, old_termios->c_cc, NCC)) printk("c_cc changed\n"); } baudrate = tiosp->c_cflag & CBAUD; if (baudrate & CBAUDEX) { baudrate &= ~CBAUDEX; if ((baudrate < 1) || (baudrate > 4)) tiosp->c_cflag &= ~CBAUDEX; else baudrate += 15; } baudrate = gs_baudrates[baudrate]; if ((tiosp->c_cflag & CBAUD) == B38400) { if ( (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI) baudrate = 57600; else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI) baudrate = 115200; else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI) baudrate = 230400; else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP) baudrate = 460800; else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) baudrate = (port->baud_base / port->custom_divisor); } /* I recommend using THIS instead of the mess in termios (and duplicating the above code). Next we should create a clean interface towards this variable. If your card supports arbitrary baud rates, (e.g. CD1400 or 16550 based cards) then everything will be very easy..... */ port->baud = baudrate; /* Two timer ticks seems enough to wakeup something like SLIP driver */ /* Baudrate/10 is cps. Divide by HZ to get chars per tick. */ tmp = (baudrate / 10 / HZ) * 2; if (tmp < 0) tmp = 0; if (tmp >= SERIAL_XMIT_SIZE) tmp = SERIAL_XMIT_SIZE-1; port->wakeup_chars = tmp; /* We should really wait for the characters to be all sent before changing the settings. -- CAL */ rv = gs_wait_tx_flushed (port, MAX_SCHEDULE_TIMEOUT); if (rv < 0) return /* rv */; rv = port->rd->set_real_termios(port); if (rv < 0) return /* rv */; if ((!old_termios || (old_termios->c_cflag & CRTSCTS)) && !( tiosp->c_cflag & CRTSCTS)) { tty->stopped = 0; gs_start(tty); } #ifdef tytso_patch_94Nov25_1726 /* This "makes sense", Why is it commented out? */ if (!(old_termios->c_cflag & CLOCAL) && (tty->termios->c_cflag & CLOCAL)) wake_up_interruptible(&info->open_wait); #endif func_exit(); return /* 0 */; } /* Must be called with interrupts enabled */ int gs_init_port(struct gs_port *port) { unsigned long flags; unsigned long page; save_flags (flags); if (!tmp_buf) { page = get_free_page(GFP_KERNEL); cli (); /* Don't expect this to make a difference. */ if (tmp_buf) free_page(page); else tmp_buf = (unsigned char *) page; restore_flags (flags); if (!tmp_buf) { return -ENOMEM; } } if (port->flags & ASYNC_INITIALIZED) return 0; if (!port->xmit_buf) { /* We may sleep in get_free_page() */ unsigned long tmp; tmp = get_free_page(GFP_KERNEL); /* Spinlock? */ cli (); if (port->xmit_buf) free_page (tmp); else port->xmit_buf = (unsigned char *) tmp; restore_flags (flags); if (!port->xmit_buf) return -ENOMEM; } cli(); if (port->tty) clear_bit(TTY_IO_ERROR, &port->tty->flags); port->xmit_cnt = port->xmit_head = port->xmit_tail = 0; gs_set_termios(port->tty, NULL); port->flags |= ASYNC_INITIALIZED; port->flags &= ~GS_TX_INTEN; restore_flags(flags); return 0; } int gs_setserial(struct gs_port *port, struct serial_struct *sp) { struct serial_struct sio; copy_from_user(&sio, sp, sizeof(struct serial_struct)); if (!capable(CAP_SYS_ADMIN)) { if ((sio.baud_base != port->baud_base) || (sio.close_delay != port->close_delay) || ((sio.flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK))) return(-EPERM); } port->flags = (port->flags & ~ASYNC_USR_MASK) | (sio.flags & ASYNC_USR_MASK); port->baud_base = sio.baud_base; port->close_delay = sio.close_delay; port->closing_wait = sio.closing_wait; port->custom_divisor = sio.custom_divisor; gs_set_termios (port->tty, NULL); return 0; } /*****************************************************************************/ /* * Generate the serial struct info. */ void gs_getserial(struct gs_port *port, struct serial_struct *sp) { struct serial_struct sio; memset(&sio, 0, sizeof(struct serial_struct)); sio.flags = port->flags; sio.baud_base = port->baud_base; sio.close_delay = port->close_delay; sio.closing_wait = port->closing_wait; sio.custom_divisor = port->custom_divisor; sio.hub6 = 0; /* If you want you can override these. */ sio.type = PORT_UNKNOWN; sio.xmit_fifo_size = -1; sio.line = -1; sio.port = -1; sio.irq = -1; if (port->rd->getserial) port->rd->getserial (port, &sio); copy_to_user(sp, &sio, sizeof(struct serial_struct)); } #ifdef MODULE int init_module (void) { return 0; } int cleanup_module (void) { return 0; } #endif