diff options
Diffstat (limited to 'net/irda/ircomm/ircomm_tty.c')
| -rw-r--r-- | net/irda/ircomm/ircomm_tty.c | 1406 |
1 files changed, 1406 insertions, 0 deletions
diff --git a/net/irda/ircomm/ircomm_tty.c b/net/irda/ircomm/ircomm_tty.c new file mode 100644 index 00000000..6b9d5a0e --- /dev/null +++ b/net/irda/ircomm/ircomm_tty.c @@ -0,0 +1,1406 @@ +/********************************************************************* + * + * Filename: ircomm_tty.c + * Version: 1.0 + * Description: IrCOMM serial TTY driver + * Status: Experimental. + * Author: Dag Brattli <dagb@cs.uit.no> + * Created at: Sun Jun 6 21:00:56 1999 + * Modified at: Wed Feb 23 00:09:02 2000 + * Modified by: Dag Brattli <dagb@cs.uit.no> + * Sources: serial.c and previous IrCOMM work by Takahide Higuchi + * + * Copyright (c) 1999-2000 Dag Brattli, All Rights Reserved. + * Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + * + ********************************************************************/ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/seq_file.h> +#include <linux/termios.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/interrupt.h> +#include <linux/device.h> /* for MODULE_ALIAS_CHARDEV_MAJOR */ + +#include <asm/uaccess.h> + +#include <net/irda/irda.h> +#include <net/irda/irmod.h> + +#include <net/irda/ircomm_core.h> +#include <net/irda/ircomm_param.h> +#include <net/irda/ircomm_tty_attach.h> +#include <net/irda/ircomm_tty.h> + +static int ircomm_tty_open(struct tty_struct *tty, struct file *filp); +static void ircomm_tty_close(struct tty_struct * tty, struct file *filp); +static int ircomm_tty_write(struct tty_struct * tty, + const unsigned char *buf, int count); +static int ircomm_tty_write_room(struct tty_struct *tty); +static void ircomm_tty_throttle(struct tty_struct *tty); +static void ircomm_tty_unthrottle(struct tty_struct *tty); +static int ircomm_tty_chars_in_buffer(struct tty_struct *tty); +static void ircomm_tty_flush_buffer(struct tty_struct *tty); +static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch); +static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout); +static void ircomm_tty_hangup(struct tty_struct *tty); +static void ircomm_tty_do_softint(struct work_struct *work); +static void ircomm_tty_shutdown(struct ircomm_tty_cb *self); +static void ircomm_tty_stop(struct tty_struct *tty); + +static int ircomm_tty_data_indication(void *instance, void *sap, + struct sk_buff *skb); +static int ircomm_tty_control_indication(void *instance, void *sap, + struct sk_buff *skb); +static void ircomm_tty_flow_indication(void *instance, void *sap, + LOCAL_FLOW cmd); +#ifdef CONFIG_PROC_FS +static const struct file_operations ircomm_tty_proc_fops; +#endif /* CONFIG_PROC_FS */ +static struct tty_driver *driver; + +static hashbin_t *ircomm_tty = NULL; + +static const struct tty_operations ops = { + .open = ircomm_tty_open, + .close = ircomm_tty_close, + .write = ircomm_tty_write, + .write_room = ircomm_tty_write_room, + .chars_in_buffer = ircomm_tty_chars_in_buffer, + .flush_buffer = ircomm_tty_flush_buffer, + .ioctl = ircomm_tty_ioctl, /* ircomm_tty_ioctl.c */ + .tiocmget = ircomm_tty_tiocmget, /* ircomm_tty_ioctl.c */ + .tiocmset = ircomm_tty_tiocmset, /* ircomm_tty_ioctl.c */ + .throttle = ircomm_tty_throttle, + .unthrottle = ircomm_tty_unthrottle, + .send_xchar = ircomm_tty_send_xchar, + .set_termios = ircomm_tty_set_termios, + .stop = ircomm_tty_stop, + .start = ircomm_tty_start, + .hangup = ircomm_tty_hangup, + .wait_until_sent = ircomm_tty_wait_until_sent, +#ifdef CONFIG_PROC_FS + .proc_fops = &ircomm_tty_proc_fops, +#endif /* CONFIG_PROC_FS */ +}; + +/* + * Function ircomm_tty_init() + * + * Init IrCOMM TTY layer/driver + * + */ +static int __init ircomm_tty_init(void) +{ + driver = alloc_tty_driver(IRCOMM_TTY_PORTS); + if (!driver) + return -ENOMEM; + ircomm_tty = hashbin_new(HB_LOCK); + if (ircomm_tty == NULL) { + IRDA_ERROR("%s(), can't allocate hashbin!\n", __func__); + put_tty_driver(driver); + return -ENOMEM; + } + + driver->driver_name = "ircomm"; + driver->name = "ircomm"; + driver->major = IRCOMM_TTY_MAJOR; + driver->minor_start = IRCOMM_TTY_MINOR; + driver->type = TTY_DRIVER_TYPE_SERIAL; + driver->subtype = SERIAL_TYPE_NORMAL; + driver->init_termios = tty_std_termios; + driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; + driver->flags = TTY_DRIVER_REAL_RAW; + tty_set_operations(driver, &ops); + if (tty_register_driver(driver)) { + IRDA_ERROR("%s(): Couldn't register serial driver\n", + __func__); + put_tty_driver(driver); + return -1; + } + return 0; +} + +static void __exit __ircomm_tty_cleanup(struct ircomm_tty_cb *self) +{ + IRDA_DEBUG(0, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + ircomm_tty_shutdown(self); + + self->magic = 0; + kfree(self); +} + +/* + * Function ircomm_tty_cleanup () + * + * Remove IrCOMM TTY layer/driver + * + */ +static void __exit ircomm_tty_cleanup(void) +{ + int ret; + + IRDA_DEBUG(4, "%s()\n", __func__ ); + + ret = tty_unregister_driver(driver); + if (ret) { + IRDA_ERROR("%s(), failed to unregister driver\n", + __func__); + return; + } + + hashbin_delete(ircomm_tty, (FREE_FUNC) __ircomm_tty_cleanup); + put_tty_driver(driver); +} + +/* + * Function ircomm_startup (self) + * + * + * + */ +static int ircomm_tty_startup(struct ircomm_tty_cb *self) +{ + notify_t notify; + int ret = -ENODEV; + + IRDA_DEBUG(2, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return -1;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;); + + /* Check if already open */ + if (test_and_set_bit(ASYNC_B_INITIALIZED, &self->flags)) { + IRDA_DEBUG(2, "%s(), already open so break out!\n", __func__ ); + return 0; + } + + /* Register with IrCOMM */ + irda_notify_init(¬ify); + /* These callbacks we must handle ourselves */ + notify.data_indication = ircomm_tty_data_indication; + notify.udata_indication = ircomm_tty_control_indication; + notify.flow_indication = ircomm_tty_flow_indication; + + /* Use the ircomm_tty interface for these ones */ + notify.disconnect_indication = ircomm_tty_disconnect_indication; + notify.connect_confirm = ircomm_tty_connect_confirm; + notify.connect_indication = ircomm_tty_connect_indication; + strlcpy(notify.name, "ircomm_tty", sizeof(notify.name)); + notify.instance = self; + + if (!self->ircomm) { + self->ircomm = ircomm_open(¬ify, self->service_type, + self->line); + } + if (!self->ircomm) + goto err; + + self->slsap_sel = self->ircomm->slsap_sel; + + /* Connect IrCOMM link with remote device */ + ret = ircomm_tty_attach_cable(self); + if (ret < 0) { + IRDA_ERROR("%s(), error attaching cable!\n", __func__); + goto err; + } + + return 0; +err: + clear_bit(ASYNC_B_INITIALIZED, &self->flags); + return ret; +} + +/* + * Function ircomm_block_til_ready (self, filp) + * + * + * + */ +static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self, + struct file *filp) +{ + DECLARE_WAITQUEUE(wait, current); + int retval; + int do_clocal = 0, extra_count = 0; + unsigned long flags; + struct tty_struct *tty; + + IRDA_DEBUG(2, "%s()\n", __func__ ); + + tty = self->tty; + + /* + * 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)){ + /* nonblock mode is set or port is not enabled */ + self->flags |= ASYNC_NORMAL_ACTIVE; + IRDA_DEBUG(1, "%s(), O_NONBLOCK requested!\n", __func__ ); + return 0; + } + + if (tty->termios->c_cflag & CLOCAL) { + IRDA_DEBUG(1, "%s(), doing CLOCAL!\n", __func__ ); + do_clocal = 1; + } + + /* Wait for carrier detect and the line to become + * free (i.e., not in use by the callout). While we are in + * this loop, self->open_count is dropped by one, so that + * mgsl_close() knows when to free things. We restore it upon + * exit, either normal or abnormal. + */ + + retval = 0; + add_wait_queue(&self->open_wait, &wait); + + IRDA_DEBUG(2, "%s(%d):block_til_ready before block on %s open_count=%d\n", + __FILE__,__LINE__, tty->driver->name, self->open_count ); + + /* As far as I can see, we protect open_count - Jean II */ + spin_lock_irqsave(&self->spinlock, flags); + if (!tty_hung_up_p(filp)) { + extra_count = 1; + self->open_count--; + } + spin_unlock_irqrestore(&self->spinlock, flags); + self->blocked_open++; + + while (1) { + if (tty->termios->c_cflag & CBAUD) { + /* Here, we use to lock those two guys, but + * as ircomm_param_request() does it itself, + * I don't see the point (and I see the deadlock). + * Jean II */ + self->settings.dte |= IRCOMM_RTS + IRCOMM_DTR; + + ircomm_param_request(self, IRCOMM_DTE, TRUE); + } + + current->state = TASK_INTERRUPTIBLE; + + if (tty_hung_up_p(filp) || + !test_bit(ASYNC_B_INITIALIZED, &self->flags)) { + retval = (self->flags & ASYNC_HUP_NOTIFY) ? + -EAGAIN : -ERESTARTSYS; + break; + } + + /* + * Check if link is ready now. Even if CLOCAL is + * specified, we cannot return before the IrCOMM link is + * ready + */ + if (!test_bit(ASYNC_B_CLOSING, &self->flags) && + (do_clocal || (self->settings.dce & IRCOMM_CD)) && + self->state == IRCOMM_TTY_READY) + { + break; + } + + if (signal_pending(current)) { + retval = -ERESTARTSYS; + break; + } + + IRDA_DEBUG(1, "%s(%d):block_til_ready blocking on %s open_count=%d\n", + __FILE__,__LINE__, tty->driver->name, self->open_count ); + + schedule(); + } + + __set_current_state(TASK_RUNNING); + remove_wait_queue(&self->open_wait, &wait); + + if (extra_count) { + /* ++ is not atomic, so this should be protected - Jean II */ + spin_lock_irqsave(&self->spinlock, flags); + self->open_count++; + spin_unlock_irqrestore(&self->spinlock, flags); + } + self->blocked_open--; + + IRDA_DEBUG(1, "%s(%d):block_til_ready after blocking on %s open_count=%d\n", + __FILE__,__LINE__, tty->driver->name, self->open_count); + + if (!retval) + self->flags |= ASYNC_NORMAL_ACTIVE; + + return retval; +} + +/* + * Function ircomm_tty_open (tty, filp) + * + * This routine is called when a particular tty device is opened. This + * routine is mandatory; if this routine is not filled in, the attempted + * open will fail with ENODEV. + */ +static int ircomm_tty_open(struct tty_struct *tty, struct file *filp) +{ + struct ircomm_tty_cb *self; + unsigned int line = tty->index; + unsigned long flags; + int ret; + + IRDA_DEBUG(2, "%s()\n", __func__ ); + + /* Check if instance already exists */ + self = hashbin_lock_find(ircomm_tty, line, NULL); + if (!self) { + /* No, so make new instance */ + self = kzalloc(sizeof(struct ircomm_tty_cb), GFP_KERNEL); + if (self == NULL) { + IRDA_ERROR("%s(), kmalloc failed!\n", __func__); + return -ENOMEM; + } + + self->magic = IRCOMM_TTY_MAGIC; + self->flow = FLOW_STOP; + + self->line = line; + INIT_WORK(&self->tqueue, ircomm_tty_do_softint); + self->max_header_size = IRCOMM_TTY_HDR_UNINITIALISED; + self->max_data_size = IRCOMM_TTY_DATA_UNINITIALISED; + self->close_delay = 5*HZ/10; + self->closing_wait = 30*HZ; + + /* Init some important stuff */ + init_timer(&self->watchdog_timer); + init_waitqueue_head(&self->open_wait); + init_waitqueue_head(&self->close_wait); + spin_lock_init(&self->spinlock); + + /* + * Force TTY into raw mode by default which is usually what + * we want for IrCOMM and IrLPT. This way applications will + * not have to twiddle with printcap etc. + * + * Note this is completely usafe and doesn't work properly + */ + tty->termios->c_iflag = 0; + tty->termios->c_oflag = 0; + + /* Insert into hash */ + hashbin_insert(ircomm_tty, (irda_queue_t *) self, line, NULL); + } + /* ++ is not atomic, so this should be protected - Jean II */ + spin_lock_irqsave(&self->spinlock, flags); + self->open_count++; + + tty->driver_data = self; + self->tty = tty; + spin_unlock_irqrestore(&self->spinlock, flags); + + IRDA_DEBUG(1, "%s(), %s%d, count = %d\n", __func__ , tty->driver->name, + self->line, self->open_count); + + /* Not really used by us, but lets do it anyway */ + self->tty->low_latency = (self->flags & ASYNC_LOW_LATENCY) ? 1 : 0; + + /* + * If the port is the middle of closing, bail out now + */ + if (tty_hung_up_p(filp) || + test_bit(ASYNC_B_CLOSING, &self->flags)) { + + /* Hm, why are we blocking on ASYNC_CLOSING if we + * do return -EAGAIN/-ERESTARTSYS below anyway? + * IMHO it's either not needed in the first place + * or for some reason we need to make sure the async + * closing has been finished - if so, wouldn't we + * probably better sleep uninterruptible? + */ + + if (wait_event_interruptible(self->close_wait, !test_bit(ASYNC_B_CLOSING, &self->flags))) { + IRDA_WARNING("%s - got signal while blocking on ASYNC_CLOSING!\n", + __func__); + return -ERESTARTSYS; + } + +#ifdef SERIAL_DO_RESTART + return (self->flags & ASYNC_HUP_NOTIFY) ? + -EAGAIN : -ERESTARTSYS; +#else + return -EAGAIN; +#endif + } + + /* Check if this is a "normal" ircomm device, or an irlpt device */ + if (line < 0x10) { + self->service_type = IRCOMM_3_WIRE | IRCOMM_9_WIRE; + self->settings.service_type = IRCOMM_9_WIRE; /* 9 wire as default */ + /* Jan Kiszka -> add DSR/RI -> Conform to IrCOMM spec */ + self->settings.dce = IRCOMM_CTS | IRCOMM_CD | IRCOMM_DSR | IRCOMM_RI; /* Default line settings */ + IRDA_DEBUG(2, "%s(), IrCOMM device\n", __func__ ); + } else { + IRDA_DEBUG(2, "%s(), IrLPT device\n", __func__ ); + self->service_type = IRCOMM_3_WIRE_RAW; + self->settings.service_type = IRCOMM_3_WIRE_RAW; /* Default */ + } + + ret = ircomm_tty_startup(self); + if (ret) + return ret; + + ret = ircomm_tty_block_til_ready(self, filp); + if (ret) { + IRDA_DEBUG(2, + "%s(), returning after block_til_ready with %d\n", __func__ , + ret); + + return ret; + } + return 0; +} + +/* + * Function ircomm_tty_close (tty, filp) + * + * This routine is called when a particular tty device is closed. + * + */ +static void ircomm_tty_close(struct tty_struct *tty, struct file *filp) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + unsigned long flags; + + IRDA_DEBUG(0, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + spin_lock_irqsave(&self->spinlock, flags); + + if (tty_hung_up_p(filp)) { + spin_unlock_irqrestore(&self->spinlock, flags); + + IRDA_DEBUG(0, "%s(), returning 1\n", __func__ ); + return; + } + + if ((tty->count == 1) && (self->open_count != 1)) { + /* + * Uh, oh. tty->count is 1, which means that the tty + * structure will be freed. state->count should always + * be one in these conditions. If it's greater than + * one, we've got real problems, since it means the + * serial port won't be shutdown. + */ + IRDA_DEBUG(0, "%s(), bad serial port count; " + "tty->count is 1, state->count is %d\n", __func__ , + self->open_count); + self->open_count = 1; + } + + if (--self->open_count < 0) { + IRDA_ERROR("%s(), bad serial port count for ttys%d: %d\n", + __func__, self->line, self->open_count); + self->open_count = 0; + } + if (self->open_count) { + spin_unlock_irqrestore(&self->spinlock, flags); + + IRDA_DEBUG(0, "%s(), open count > 0\n", __func__ ); + return; + } + + /* Hum... Should be test_and_set_bit ??? - Jean II */ + set_bit(ASYNC_B_CLOSING, &self->flags); + + /* We need to unlock here (we were unlocking at the end of this + * function), because tty_wait_until_sent() may schedule. + * I don't know if the rest should be protected somehow, + * so someone should check. - Jean II */ + spin_unlock_irqrestore(&self->spinlock, flags); + + /* + * 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 (self->closing_wait != ASYNC_CLOSING_WAIT_NONE) + tty_wait_until_sent_from_close(tty, self->closing_wait); + + ircomm_tty_shutdown(self); + + tty_driver_flush_buffer(tty); + tty_ldisc_flush(tty); + + tty->closing = 0; + self->tty = NULL; + + if (self->blocked_open) { + if (self->close_delay) + schedule_timeout_interruptible(self->close_delay); + wake_up_interruptible(&self->open_wait); + } + + self->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING); + wake_up_interruptible(&self->close_wait); +} + +/* + * Function ircomm_tty_flush_buffer (tty) + * + * + * + */ +static void ircomm_tty_flush_buffer(struct tty_struct *tty) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + /* + * Let do_softint() do this to avoid race condition with + * do_softint() ;-) + */ + schedule_work(&self->tqueue); +} + +/* + * Function ircomm_tty_do_softint (work) + * + * We use this routine to give the write wakeup to the user at at a + * safe time (as fast as possible after write have completed). This + * can be compared to the Tx interrupt. + */ +static void ircomm_tty_do_softint(struct work_struct *work) +{ + struct ircomm_tty_cb *self = + container_of(work, struct ircomm_tty_cb, tqueue); + struct tty_struct *tty; + unsigned long flags; + struct sk_buff *skb, *ctrl_skb; + + IRDA_DEBUG(2, "%s()\n", __func__ ); + + if (!self || self->magic != IRCOMM_TTY_MAGIC) + return; + + tty = self->tty; + if (!tty) + return; + + /* Unlink control buffer */ + spin_lock_irqsave(&self->spinlock, flags); + + ctrl_skb = self->ctrl_skb; + self->ctrl_skb = NULL; + + spin_unlock_irqrestore(&self->spinlock, flags); + + /* Flush control buffer if any */ + if(ctrl_skb) { + if(self->flow == FLOW_START) + ircomm_control_request(self->ircomm, ctrl_skb); + /* Drop reference count - see ircomm_ttp_data_request(). */ + dev_kfree_skb(ctrl_skb); + } + + if (tty->hw_stopped) + return; + + /* Unlink transmit buffer */ + spin_lock_irqsave(&self->spinlock, flags); + + skb = self->tx_skb; + self->tx_skb = NULL; + + spin_unlock_irqrestore(&self->spinlock, flags); + + /* Flush transmit buffer if any */ + if (skb) { + ircomm_tty_do_event(self, IRCOMM_TTY_DATA_REQUEST, skb, NULL); + /* Drop reference count - see ircomm_ttp_data_request(). */ + dev_kfree_skb(skb); + } + + /* Check if user (still) wants to be waken up */ + tty_wakeup(tty); +} + +/* + * Function ircomm_tty_write (tty, buf, count) + * + * This routine is called by the kernel to write a series of characters + * to the tty device. The characters may come from user space or kernel + * space. This routine will return the number of characters actually + * accepted for writing. This routine is mandatory. + */ +static int ircomm_tty_write(struct tty_struct *tty, + const unsigned char *buf, int count) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + unsigned long flags; + struct sk_buff *skb; + int tailroom = 0; + int len = 0; + int size; + + IRDA_DEBUG(2, "%s(), count=%d, hw_stopped=%d\n", __func__ , count, + tty->hw_stopped); + + IRDA_ASSERT(self != NULL, return -1;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;); + + /* We may receive packets from the TTY even before we have finished + * our setup. Not cool. + * The problem is that we don't know the final header and data size + * to create the proper skb, so any skb we would create would have + * bogus header and data size, so need care. + * We use a bogus header size to safely detect this condition. + * Another problem is that hw_stopped was set to 0 way before it + * should be, so we would drop this skb. It should now be fixed. + * One option is to not accept data until we are properly setup. + * But, I suspect that when it happens, the ppp line discipline + * just "drops" the data, which might screw up connect scripts. + * The second option is to create a "safe skb", with large header + * and small size (see ircomm_tty_open() for values). + * We just need to make sure that when the real values get filled, + * we don't mess up the original "safe skb" (see tx_data_size). + * Jean II */ + if (self->max_header_size == IRCOMM_TTY_HDR_UNINITIALISED) { + IRDA_DEBUG(1, "%s() : not initialised\n", __func__); +#ifdef IRCOMM_NO_TX_BEFORE_INIT + /* We didn't consume anything, TTY will retry */ + return 0; +#endif + } + + if (count < 1) + return 0; + + /* Protect our manipulation of self->tx_skb and related */ + spin_lock_irqsave(&self->spinlock, flags); + + /* Fetch current transmit buffer */ + skb = self->tx_skb; + + /* + * Send out all the data we get, possibly as multiple fragmented + * frames, but this will only happen if the data is larger than the + * max data size. The normal case however is just the opposite, and + * this function may be called multiple times, and will then actually + * defragment the data and send it out as one packet as soon as + * possible, but at a safer point in time + */ + while (count) { + size = count; + + /* Adjust data size to the max data size */ + if (size > self->max_data_size) + size = self->max_data_size; + + /* + * Do we already have a buffer ready for transmit, or do + * we need to allocate a new frame + */ + if (skb) { + /* + * Any room for more data at the end of the current + * transmit buffer? Cannot use skb_tailroom, since + * dev_alloc_skb gives us a larger skb than we + * requested + * Note : use tx_data_size, because max_data_size + * may have changed and we don't want to overwrite + * the skb. - Jean II + */ + if ((tailroom = (self->tx_data_size - skb->len)) > 0) { + /* Adjust data to tailroom */ + if (size > tailroom) + size = tailroom; + } else { + /* + * Current transmit frame is full, so break + * out, so we can send it as soon as possible + */ + break; + } + } else { + /* Prepare a full sized frame */ + skb = alloc_skb(self->max_data_size+ + self->max_header_size, + GFP_ATOMIC); + if (!skb) { + spin_unlock_irqrestore(&self->spinlock, flags); + return -ENOBUFS; + } + skb_reserve(skb, self->max_header_size); + self->tx_skb = skb; + /* Remember skb size because max_data_size may + * change later on - Jean II */ + self->tx_data_size = self->max_data_size; + } + + /* Copy data */ + memcpy(skb_put(skb,size), buf + len, size); + + count -= size; + len += size; + } + + spin_unlock_irqrestore(&self->spinlock, flags); + + /* + * Schedule a new thread which will transmit the frame as soon + * as possible, but at a safe point in time. We do this so the + * "user" can give us data multiple times, as PPP does (because of + * its 256 byte tx buffer). We will then defragment and send out + * all this data as one single packet. + */ + schedule_work(&self->tqueue); + + return len; +} + +/* + * Function ircomm_tty_write_room (tty) + * + * This routine returns the numbers of characters the tty driver will + * accept for queuing to be written. This number is subject to change as + * output buffers get emptied, or if the output flow control is acted. + */ +static int ircomm_tty_write_room(struct tty_struct *tty) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + unsigned long flags; + int ret; + + IRDA_ASSERT(self != NULL, return -1;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;); + +#ifdef IRCOMM_NO_TX_BEFORE_INIT + /* max_header_size tells us if the channel is initialised or not. */ + if (self->max_header_size == IRCOMM_TTY_HDR_UNINITIALISED) + /* Don't bother us yet */ + return 0; +#endif + + /* Check if we are allowed to transmit any data. + * hw_stopped is the regular flow control. + * Jean II */ + if (tty->hw_stopped) + ret = 0; + else { + spin_lock_irqsave(&self->spinlock, flags); + if (self->tx_skb) + ret = self->tx_data_size - self->tx_skb->len; + else + ret = self->max_data_size; + spin_unlock_irqrestore(&self->spinlock, flags); + } + IRDA_DEBUG(2, "%s(), ret=%d\n", __func__ , ret); + + return ret; +} + +/* + * Function ircomm_tty_wait_until_sent (tty, timeout) + * + * This routine waits until the device has written out all of the + * characters in its transmitter FIFO. + */ +static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + unsigned long orig_jiffies, poll_time; + unsigned long flags; + + IRDA_DEBUG(2, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + orig_jiffies = jiffies; + + /* Set poll time to 200 ms */ + poll_time = IRDA_MIN(timeout, msecs_to_jiffies(200)); + + spin_lock_irqsave(&self->spinlock, flags); + while (self->tx_skb && self->tx_skb->len) { + spin_unlock_irqrestore(&self->spinlock, flags); + schedule_timeout_interruptible(poll_time); + spin_lock_irqsave(&self->spinlock, flags); + if (signal_pending(current)) + break; + if (timeout && time_after(jiffies, orig_jiffies + timeout)) + break; + } + spin_unlock_irqrestore(&self->spinlock, flags); + current->state = TASK_RUNNING; +} + +/* + * Function ircomm_tty_throttle (tty) + * + * This routine notifies the tty driver that input buffers for the line + * discipline are close to full, and it should somehow signal that no + * more characters should be sent to the tty. + */ +static void ircomm_tty_throttle(struct tty_struct *tty) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + + IRDA_DEBUG(2, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + /* Software flow control? */ + if (I_IXOFF(tty)) + ircomm_tty_send_xchar(tty, STOP_CHAR(tty)); + + /* Hardware flow control? */ + if (tty->termios->c_cflag & CRTSCTS) { + self->settings.dte &= ~IRCOMM_RTS; + self->settings.dte |= IRCOMM_DELTA_RTS; + + ircomm_param_request(self, IRCOMM_DTE, TRUE); + } + + ircomm_flow_request(self->ircomm, FLOW_STOP); +} + +/* + * Function ircomm_tty_unthrottle (tty) + * + * This routine notifies the tty drivers that it should signals that + * characters can now be sent to the tty without fear of overrunning the + * input buffers of the line disciplines. + */ +static void ircomm_tty_unthrottle(struct tty_struct *tty) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + + IRDA_DEBUG(2, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + /* Using software flow control? */ + if (I_IXOFF(tty)) { + ircomm_tty_send_xchar(tty, START_CHAR(tty)); + } + + /* Using hardware flow control? */ + if (tty->termios->c_cflag & CRTSCTS) { + self->settings.dte |= (IRCOMM_RTS|IRCOMM_DELTA_RTS); + + ircomm_param_request(self, IRCOMM_DTE, TRUE); + IRDA_DEBUG(1, "%s(), FLOW_START\n", __func__ ); + } + ircomm_flow_request(self->ircomm, FLOW_START); +} + +/* + * Function ircomm_tty_chars_in_buffer (tty) + * + * Indicates if there are any data in the buffer + * + */ +static int ircomm_tty_chars_in_buffer(struct tty_struct *tty) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + unsigned long flags; + int len = 0; + + IRDA_ASSERT(self != NULL, return -1;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;); + + spin_lock_irqsave(&self->spinlock, flags); + + if (self->tx_skb) + len = self->tx_skb->len; + + spin_unlock_irqrestore(&self->spinlock, flags); + + return len; +} + +static void ircomm_tty_shutdown(struct ircomm_tty_cb *self) +{ + unsigned long flags; + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + IRDA_DEBUG(0, "%s()\n", __func__ ); + + if (!test_and_clear_bit(ASYNC_B_INITIALIZED, &self->flags)) + return; + + ircomm_tty_detach_cable(self); + + spin_lock_irqsave(&self->spinlock, flags); + + del_timer(&self->watchdog_timer); + + /* Free parameter buffer */ + if (self->ctrl_skb) { + dev_kfree_skb(self->ctrl_skb); + self->ctrl_skb = NULL; + } + + /* Free transmit buffer */ + if (self->tx_skb) { + dev_kfree_skb(self->tx_skb); + self->tx_skb = NULL; + } + + if (self->ircomm) { + ircomm_close(self->ircomm); + self->ircomm = NULL; + } + + spin_unlock_irqrestore(&self->spinlock, flags); +} + +/* + * Function ircomm_tty_hangup (tty) + * + * This routine notifies the tty driver that it should hangup the tty + * device. + * + */ +static void ircomm_tty_hangup(struct tty_struct *tty) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + unsigned long flags; + + IRDA_DEBUG(0, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + /* ircomm_tty_flush_buffer(tty); */ + ircomm_tty_shutdown(self); + + /* I guess we need to lock here - Jean II */ + spin_lock_irqsave(&self->spinlock, flags); + self->flags &= ~ASYNC_NORMAL_ACTIVE; + self->tty = NULL; + self->open_count = 0; + spin_unlock_irqrestore(&self->spinlock, flags); + + wake_up_interruptible(&self->open_wait); +} + +/* + * Function ircomm_tty_send_xchar (tty, ch) + * + * This routine is used to send a high-priority XON/XOFF character to + * the device. + */ +static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch) +{ + IRDA_DEBUG(0, "%s(), not impl\n", __func__ ); +} + +/* + * Function ircomm_tty_start (tty) + * + * This routine notifies the tty driver that it resume sending + * characters to the tty device. + */ +void ircomm_tty_start(struct tty_struct *tty) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + + ircomm_flow_request(self->ircomm, FLOW_START); +} + +/* + * Function ircomm_tty_stop (tty) + * + * This routine notifies the tty driver that it should stop outputting + * characters to the tty device. + */ +static void ircomm_tty_stop(struct tty_struct *tty) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data; + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + ircomm_flow_request(self->ircomm, FLOW_STOP); +} + +/* + * Function ircomm_check_modem_status (self) + * + * Check for any changes in the DCE's line settings. This function should + * be called whenever the dce parameter settings changes, to update the + * flow control settings and other things + */ +void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self) +{ + struct tty_struct *tty; + int status; + + IRDA_DEBUG(0, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + tty = self->tty; + + status = self->settings.dce; + + if (status & IRCOMM_DCE_DELTA_ANY) { + /*wake_up_interruptible(&self->delta_msr_wait);*/ + } + if ((self->flags & ASYNC_CHECK_CD) && (status & IRCOMM_DELTA_CD)) { + IRDA_DEBUG(2, + "%s(), ircomm%d CD now %s...\n", __func__ , self->line, + (status & IRCOMM_CD) ? "on" : "off"); + + if (status & IRCOMM_CD) { + wake_up_interruptible(&self->open_wait); + } else { + IRDA_DEBUG(2, + "%s(), Doing serial hangup..\n", __func__ ); + if (tty) + tty_hangup(tty); + + /* Hangup will remote the tty, so better break out */ + return; + } + } + if (self->flags & ASYNC_CTS_FLOW) { + if (tty->hw_stopped) { + if (status & IRCOMM_CTS) { + IRDA_DEBUG(2, + "%s(), CTS tx start...\n", __func__ ); + tty->hw_stopped = 0; + + /* Wake up processes blocked on open */ + wake_up_interruptible(&self->open_wait); + + schedule_work(&self->tqueue); + return; + } + } else { + if (!(status & IRCOMM_CTS)) { + IRDA_DEBUG(2, + "%s(), CTS tx stop...\n", __func__ ); + tty->hw_stopped = 1; + } + } + } +} + +/* + * Function ircomm_tty_data_indication (instance, sap, skb) + * + * Handle incoming data, and deliver it to the line discipline + * + */ +static int ircomm_tty_data_indication(void *instance, void *sap, + struct sk_buff *skb) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance; + + IRDA_DEBUG(2, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return -1;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;); + IRDA_ASSERT(skb != NULL, return -1;); + + if (!self->tty) { + IRDA_DEBUG(0, "%s(), no tty!\n", __func__ ); + return 0; + } + + /* + * If we receive data when hardware is stopped then something is wrong. + * We try to poll the peers line settings to check if we are up todate. + * Devices like WinCE can do this, and since they don't send any + * params, we can just as well declare the hardware for running. + */ + if (self->tty->hw_stopped && (self->flow == FLOW_START)) { + IRDA_DEBUG(0, "%s(), polling for line settings!\n", __func__ ); + ircomm_param_request(self, IRCOMM_POLL, TRUE); + + /* We can just as well declare the hardware for running */ + ircomm_tty_send_initial_parameters(self); + ircomm_tty_link_established(self); + } + + /* + * Use flip buffer functions since the code may be called from interrupt + * context + */ + tty_insert_flip_string(self->tty, skb->data, skb->len); + tty_flip_buffer_push(self->tty); + + /* No need to kfree_skb - see ircomm_ttp_data_indication() */ + + return 0; +} + +/* + * Function ircomm_tty_control_indication (instance, sap, skb) + * + * Parse all incoming parameters (easy!) + * + */ +static int ircomm_tty_control_indication(void *instance, void *sap, + struct sk_buff *skb) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance; + int clen; + + IRDA_DEBUG(4, "%s()\n", __func__ ); + + IRDA_ASSERT(self != NULL, return -1;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;); + IRDA_ASSERT(skb != NULL, return -1;); + + clen = skb->data[0]; + + irda_param_extract_all(self, skb->data+1, IRDA_MIN(skb->len-1, clen), + &ircomm_param_info); + + /* No need to kfree_skb - see ircomm_control_indication() */ + + return 0; +} + +/* + * Function ircomm_tty_flow_indication (instance, sap, cmd) + * + * This function is called by IrTTP when it wants us to slow down the + * transmission of data. We just mark the hardware as stopped, and wait + * for IrTTP to notify us that things are OK again. + */ +static void ircomm_tty_flow_indication(void *instance, void *sap, + LOCAL_FLOW cmd) +{ + struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance; + struct tty_struct *tty; + + IRDA_ASSERT(self != NULL, return;); + IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;); + + tty = self->tty; + + switch (cmd) { + case FLOW_START: + IRDA_DEBUG(2, "%s(), hw start!\n", __func__ ); + tty->hw_stopped = 0; + + /* ircomm_tty_do_softint will take care of the rest */ + schedule_work(&self->tqueue); + break; + default: /* If we get here, something is very wrong, better stop */ + case FLOW_STOP: + IRDA_DEBUG(2, "%s(), hw stopped!\n", __func__ ); + tty->hw_stopped = 1; + break; + } + self->flow = cmd; +} + +#ifdef CONFIG_PROC_FS +static void ircomm_tty_line_info(struct ircomm_tty_cb *self, struct seq_file *m) +{ + char sep; + + seq_printf(m, "State: %s\n", ircomm_tty_state[self->state]); + + seq_puts(m, "Service type: "); + if (self->service_type & IRCOMM_9_WIRE) + seq_puts(m, "9_WIRE"); + else if (self->service_type & IRCOMM_3_WIRE) + seq_puts(m, "3_WIRE"); + else if (self->service_type & IRCOMM_3_WIRE_RAW) + seq_puts(m, "3_WIRE_RAW"); + else + seq_puts(m, "No common service type!\n"); + seq_putc(m, '\n'); + + seq_printf(m, "Port name: %s\n", self->settings.port_name); + + seq_printf(m, "DTE status:"); + sep = ' '; + if (self->settings.dte & IRCOMM_RTS) { + seq_printf(m, "%cRTS", sep); + sep = '|'; + } + if (self->settings.dte & IRCOMM_DTR) { + seq_printf(m, "%cDTR", sep); + sep = '|'; + } + seq_putc(m, '\n'); + + seq_puts(m, "DCE status:"); + sep = ' '; + if (self->settings.dce & IRCOMM_CTS) { + seq_printf(m, "%cCTS", sep); + sep = '|'; + } + if (self->settings.dce & IRCOMM_DSR) { + seq_printf(m, "%cDSR", sep); + sep = '|'; + } + if (self->settings.dce & IRCOMM_CD) { + seq_printf(m, "%cCD", sep); + sep = '|'; + } + if (self->settings.dce & IRCOMM_RI) { + seq_printf(m, "%cRI", sep); + sep = '|'; + } + seq_putc(m, '\n'); + + seq_puts(m, "Configuration: "); + if (!self->settings.null_modem) + seq_puts(m, "DTE <-> DCE\n"); + else + seq_puts(m, "DTE <-> DTE (null modem emulation)\n"); + + seq_printf(m, "Data rate: %d\n", self->settings.data_rate); + + seq_puts(m, "Flow control:"); + sep = ' '; + if (self->settings.flow_control & IRCOMM_XON_XOFF_IN) { + seq_printf(m, "%cXON_XOFF_IN", sep); + sep = '|'; + } + if (self->settings.flow_control & IRCOMM_XON_XOFF_OUT) { + seq_printf(m, "%cXON_XOFF_OUT", sep); + sep = '|'; + } + if (self->settings.flow_control & IRCOMM_RTS_CTS_IN) { + seq_printf(m, "%cRTS_CTS_IN", sep); + sep = '|'; + } + if (self->settings.flow_control & IRCOMM_RTS_CTS_OUT) { + seq_printf(m, "%cRTS_CTS_OUT", sep); + sep = '|'; + } + if (self->settings.flow_control & IRCOMM_DSR_DTR_IN) { + seq_printf(m, "%cDSR_DTR_IN", sep); + sep = '|'; + } + if (self->settings.flow_control & IRCOMM_DSR_DTR_OUT) { + seq_printf(m, "%cDSR_DTR_OUT", sep); + sep = '|'; + } + if (self->settings.flow_control & IRCOMM_ENQ_ACK_IN) { + seq_printf(m, "%cENQ_ACK_IN", sep); + sep = '|'; + } + if (self->settings.flow_control & IRCOMM_ENQ_ACK_OUT) { + seq_printf(m, "%cENQ_ACK_OUT", sep); + sep = '|'; + } + seq_putc(m, '\n'); + + seq_puts(m, "Flags:"); + sep = ' '; + if (self->flags & ASYNC_CTS_FLOW) { + seq_printf(m, "%cASYNC_CTS_FLOW", sep); + sep = '|'; + } + if (self->flags & ASYNC_CHECK_CD) { + seq_printf(m, "%cASYNC_CHECK_CD", sep); + sep = '|'; + } + if (self->flags & ASYNC_INITIALIZED) { + seq_printf(m, "%cASYNC_INITIALIZED", sep); + sep = '|'; + } + if (self->flags & ASYNC_LOW_LATENCY) { + seq_printf(m, "%cASYNC_LOW_LATENCY", sep); + sep = '|'; + } + if (self->flags & ASYNC_CLOSING) { + seq_printf(m, "%cASYNC_CLOSING", sep); + sep = '|'; + } + if (self->flags & ASYNC_NORMAL_ACTIVE) { + seq_printf(m, "%cASYNC_NORMAL_ACTIVE", sep); + sep = '|'; + } + seq_putc(m, '\n'); + + seq_printf(m, "Role: %s\n", self->client ? "client" : "server"); + seq_printf(m, "Open count: %d\n", self->open_count); + seq_printf(m, "Max data size: %d\n", self->max_data_size); + seq_printf(m, "Max header size: %d\n", self->max_header_size); + + if (self->tty) + seq_printf(m, "Hardware: %s\n", + self->tty->hw_stopped ? "Stopped" : "Running"); +} + +static int ircomm_tty_proc_show(struct seq_file *m, void *v) +{ + struct ircomm_tty_cb *self; + unsigned long flags; + + spin_lock_irqsave(&ircomm_tty->hb_spinlock, flags); + + self = (struct ircomm_tty_cb *) hashbin_get_first(ircomm_tty); + while (self != NULL) { + if (self->magic != IRCOMM_TTY_MAGIC) + break; + + ircomm_tty_line_info(self, m); + self = (struct ircomm_tty_cb *) hashbin_get_next(ircomm_tty); + } + spin_unlock_irqrestore(&ircomm_tty->hb_spinlock, flags); + return 0; +} + +static int ircomm_tty_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, ircomm_tty_proc_show, NULL); +} + +static const struct file_operations ircomm_tty_proc_fops = { + .owner = THIS_MODULE, + .open = ircomm_tty_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; +#endif /* CONFIG_PROC_FS */ + +MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>"); +MODULE_DESCRIPTION("IrCOMM serial TTY driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CHARDEV_MAJOR(IRCOMM_TTY_MAJOR); + +module_init(ircomm_tty_init); +module_exit(ircomm_tty_cleanup); |