From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- drivers/net/irda/irtty-sir.c | 642 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 642 insertions(+) create mode 100644 drivers/net/irda/irtty-sir.c (limited to 'drivers/net/irda/irtty-sir.c') diff --git a/drivers/net/irda/irtty-sir.c b/drivers/net/irda/irtty-sir.c new file mode 100644 index 0000000..7d23aa3 --- /dev/null +++ b/drivers/net/irda/irtty-sir.c @@ -0,0 +1,642 @@ +/********************************************************************* + * + * Filename: irtty-sir.c + * Version: 2.0 + * Description: IrDA line discipline implementation + * Status: Experimental. + * Author: Dag Brattli + * Created at: Tue Dec 9 21:18:38 1997 + * Modified at: Sun Oct 27 22:13:30 2002 + * Modified by: Martin Diehl + * Sources: slip.c by Laurence Culhane, + * Fred N. van Kempen, + * + * Copyright (c) 1998-2000 Dag Brattli, + * Copyright (c) 2002 Martin Diehl, + * All Rights Reserved. + * + * 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. + * + * Neither Dag Brattli nor University of Tromsų admit liability nor + * provide warranty for any of this software. This material is + * provided "AS-IS" and at no charge. + * + ********************************************************************/ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "sir-dev.h" +#include "irtty-sir.h" + +static int qos_mtt_bits = 0x03; /* 5 ms or more */ + +module_param(qos_mtt_bits, int, 0); +MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time"); + +/* ------------------------------------------------------- */ + +/* device configuration callbacks always invoked with irda-thread context */ + +/* find out, how many chars we have in buffers below us + * this is allowed to lie, i.e. return less chars than we + * actually have. The returned value is used to determine + * how long the irdathread should wait before doing the + * real blocking wait_until_sent() + */ + +static int irtty_chars_in_buffer(struct sir_dev *dev) +{ + struct sirtty_cb *priv = dev->priv; + + IRDA_ASSERT(priv != NULL, return -1;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return -1;); + + return priv->tty->driver->chars_in_buffer(priv->tty); +} + +/* Wait (sleep) until underlaying hardware finished transmission + * i.e. hardware buffers are drained + * this must block and not return before all characters are really sent + * + * If the tty sits on top of a 16550A-like uart, there are typically + * up to 16 bytes in the fifo - f.e. 9600 bps 8N1 needs 16.7 msec + * + * With usbserial the uart-fifo is basically replaced by the converter's + * outgoing endpoint buffer, which can usually hold 64 bytes (at least). + * With pl2303 it appears we are safe with 60msec here. + * + * I really wish all serial drivers would provide + * correct implementation of wait_until_sent() + */ + +#define USBSERIAL_TX_DONE_DELAY 60 + +static void irtty_wait_until_sent(struct sir_dev *dev) +{ + struct sirtty_cb *priv = dev->priv; + struct tty_struct *tty; + + IRDA_ASSERT(priv != NULL, return;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return;); + + tty = priv->tty; + if (tty->driver->wait_until_sent) { + lock_kernel(); + tty->driver->wait_until_sent(tty, msecs_to_jiffies(100)); + unlock_kernel(); + } + else { + msleep(USBSERIAL_TX_DONE_DELAY); + } +} + +/* + * Function irtty_change_speed (dev, speed) + * + * Change the speed of the serial port. + * + * This may sleep in set_termios (usbserial driver f.e.) and must + * not be called from interrupt/timer/tasklet therefore. + * All such invocations are deferred to kIrDAd now so we can sleep there. + */ + +static int irtty_change_speed(struct sir_dev *dev, unsigned speed) +{ + struct sirtty_cb *priv = dev->priv; + struct tty_struct *tty; + struct termios old_termios; + int cflag; + + IRDA_ASSERT(priv != NULL, return -1;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return -1;); + + tty = priv->tty; + + lock_kernel(); + old_termios = *(tty->termios); + cflag = tty->termios->c_cflag; + + cflag &= ~CBAUD; + + IRDA_DEBUG(2, "%s(), Setting speed to %d\n", __FUNCTION__, speed); + + switch (speed) { + 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; + } + + tty->termios->c_cflag = cflag; + if (tty->driver->set_termios) + tty->driver->set_termios(tty, &old_termios); + unlock_kernel(); + + priv->io.speed = speed; + + return 0; +} + +/* + * Function irtty_set_dtr_rts (dev, dtr, rts) + * + * This function can be used by dongles etc. to set or reset the status + * of the dtr and rts lines + */ + +static int irtty_set_dtr_rts(struct sir_dev *dev, int dtr, int rts) +{ + struct sirtty_cb *priv = dev->priv; + int set = 0; + int clear = 0; + + IRDA_ASSERT(priv != NULL, return -1;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return -1;); + + if (rts) + set |= TIOCM_RTS; + else + clear |= TIOCM_RTS; + if (dtr) + set |= TIOCM_DTR; + else + clear |= TIOCM_DTR; + + /* + * We can't use ioctl() because it expects a non-null file structure, + * and we don't have that here. + * This function is not yet defined for all tty driver, so + * let's be careful... Jean II + */ + IRDA_ASSERT(priv->tty->driver->tiocmset != NULL, return -1;); + priv->tty->driver->tiocmset(priv->tty, NULL, set, clear); + + return 0; +} + +/* ------------------------------------------------------- */ + +/* called from sir_dev when there is more data to send + * context is either netdev->hard_xmit or some transmit-completion bh + * i.e. we are under spinlock here and must not sleep. + */ + +static int irtty_do_write(struct sir_dev *dev, const unsigned char *ptr, size_t len) +{ + struct sirtty_cb *priv = dev->priv; + struct tty_struct *tty; + int writelen; + + IRDA_ASSERT(priv != NULL, return -1;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return -1;); + + tty = priv->tty; + if (!tty->driver->write) + return 0; + tty->flags |= (1 << TTY_DO_WRITE_WAKEUP); + if (tty->driver->write_room) { + writelen = tty->driver->write_room(tty); + if (writelen > len) + writelen = len; + } + else + writelen = len; + return tty->driver->write(tty, ptr, writelen); +} + +/* ------------------------------------------------------- */ + +/* irda line discipline callbacks */ + +/* + * Function irtty_receive_buf( tty, cp, count) + * + * Handle the 'receiver data ready' interrupt. This function is called + * by the 'tty_io' module in the kernel when a block of IrDA data has + * been received, which can now be decapsulated and delivered for + * further processing + * + * calling context depends on underlying driver and tty->low_latency! + * for example (low_latency: 1 / 0): + * serial.c: uart-interrupt / softint + * usbserial: urb-complete-interrupt / softint + */ + +static void irtty_receive_buf(struct tty_struct *tty, const unsigned char *cp, + char *fp, int count) +{ + struct sir_dev *dev; + struct sirtty_cb *priv = tty->disc_data; + int i; + + IRDA_ASSERT(priv != NULL, return;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return;); + + if (unlikely(count==0)) /* yes, this happens */ + return; + + dev = priv->dev; + if (!dev) { + IRDA_WARNING("%s(), not ready yet!\n", __FUNCTION__); + return; + } + + for (i = 0; i < count; i++) { + /* + * Characters received with a parity error, etc? + */ + if (fp && *fp++) { + IRDA_DEBUG(0, "Framing or parity error!\n"); + sirdev_receive(dev, NULL, 0); /* notify sir_dev (updating stats) */ + return; + } + } + + sirdev_receive(dev, cp, count); +} + +/* + * Function irtty_receive_room (tty) + * + * Used by the TTY to find out how much data we can receive at a time + * +*/ +static int irtty_receive_room(struct tty_struct *tty) +{ + struct sirtty_cb *priv = tty->disc_data; + + IRDA_ASSERT(priv != NULL, return 0;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return 0;); + + return 65536; /* We can handle an infinite amount of data. :-) */ +} + +/* + * Function irtty_write_wakeup (tty) + * + * Called by the driver when there's room for more data. If we have + * more packets to send, we send them here. + * + */ +static void irtty_write_wakeup(struct tty_struct *tty) +{ + struct sirtty_cb *priv = tty->disc_data; + + IRDA_ASSERT(priv != NULL, return;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return;); + + tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); + + if (priv->dev) + sirdev_write_complete(priv->dev); +} + +/* ------------------------------------------------------- */ + +/* + * Function irtty_stop_receiver (tty, stop) + * + */ + +static inline void irtty_stop_receiver(struct tty_struct *tty, int stop) +{ + struct termios old_termios; + int cflag; + + lock_kernel(); + old_termios = *(tty->termios); + cflag = tty->termios->c_cflag; + + if (stop) + cflag &= ~CREAD; + else + cflag |= CREAD; + + tty->termios->c_cflag = cflag; + if (tty->driver->set_termios) + tty->driver->set_termios(tty, &old_termios); + unlock_kernel(); +} + +/*****************************************************************/ + +/* serialize ldisc open/close with sir_dev */ +static DECLARE_MUTEX(irtty_sem); + +/* notifier from sir_dev when irda% device gets opened (ifup) */ + +static int irtty_start_dev(struct sir_dev *dev) +{ + struct sirtty_cb *priv; + struct tty_struct *tty; + + /* serialize with ldisc open/close */ + down(&irtty_sem); + + priv = dev->priv; + if (unlikely(!priv || priv->magic!=IRTTY_MAGIC)) { + up(&irtty_sem); + return -ESTALE; + } + + tty = priv->tty; + + if (tty->driver->start) + tty->driver->start(tty); + /* Make sure we can receive more data */ + irtty_stop_receiver(tty, FALSE); + + up(&irtty_sem); + return 0; +} + +/* notifier from sir_dev when irda% device gets closed (ifdown) */ + +static int irtty_stop_dev(struct sir_dev *dev) +{ + struct sirtty_cb *priv; + struct tty_struct *tty; + + /* serialize with ldisc open/close */ + down(&irtty_sem); + + priv = dev->priv; + if (unlikely(!priv || priv->magic!=IRTTY_MAGIC)) { + up(&irtty_sem); + return -ESTALE; + } + + tty = priv->tty; + + /* Make sure we don't receive more data */ + irtty_stop_receiver(tty, TRUE); + if (tty->driver->stop) + tty->driver->stop(tty); + + up(&irtty_sem); + + return 0; +} + +/* ------------------------------------------------------- */ + +static struct sir_driver sir_tty_drv = { + .owner = THIS_MODULE, + .driver_name = "sir_tty", + .start_dev = irtty_start_dev, + .stop_dev = irtty_stop_dev, + .do_write = irtty_do_write, + .chars_in_buffer = irtty_chars_in_buffer, + .wait_until_sent = irtty_wait_until_sent, + .set_speed = irtty_change_speed, + .set_dtr_rts = irtty_set_dtr_rts, +}; + +/* ------------------------------------------------------- */ + +/* + * Function irtty_ioctl (tty, file, cmd, arg) + * + * The Swiss army knife of system calls :-) + * + */ +static int irtty_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) +{ + struct irtty_info { char name[6]; } info; + struct sir_dev *dev; + struct sirtty_cb *priv = tty->disc_data; + int err = 0; + + IRDA_ASSERT(priv != NULL, return -ENODEV;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return -EBADR;); + + IRDA_DEBUG(3, "%s(cmd=0x%X)\n", __FUNCTION__, cmd); + + dev = priv->dev; + IRDA_ASSERT(dev != NULL, return -1;); + + switch (cmd) { + case TCGETS: + case TCGETA: + err = n_tty_ioctl(tty, file, cmd, arg); + break; + + case IRTTY_IOCTDONGLE: + /* this call blocks for completion */ + err = sirdev_set_dongle(dev, (IRDA_DONGLE) arg); + break; + + case IRTTY_IOCGET: + IRDA_ASSERT(dev->netdev != NULL, return -1;); + + memset(&info, 0, sizeof(info)); + strncpy(info.name, dev->netdev->name, sizeof(info.name)-1); + + if (copy_to_user((void __user *)arg, &info, sizeof(info))) + err = -EFAULT; + break; + default: + err = -ENOIOCTLCMD; + break; + } + return err; +} + + +/* + * Function irtty_open(tty) + * + * This function is called by the TTY module when the IrDA line + * discipline is called for. Because we are sure the tty line exists, + * we only have to link it to a free IrDA channel. + */ +static int irtty_open(struct tty_struct *tty) +{ + struct sir_dev *dev; + struct sirtty_cb *priv; + int ret = 0; + + /* Module stuff handled via irda_ldisc.owner - Jean II */ + + /* First make sure we're not already connected. */ + if (tty->disc_data != NULL) { + priv = tty->disc_data; + if (priv && priv->magic == IRTTY_MAGIC) { + ret = -EEXIST; + goto out; + } + tty->disc_data = NULL; /* ### */ + } + + /* stop the underlying driver */ + irtty_stop_receiver(tty, TRUE); + if (tty->driver->stop) + tty->driver->stop(tty); + + if (tty->driver->flush_buffer) + tty->driver->flush_buffer(tty); + + /* apply mtt override */ + sir_tty_drv.qos_mtt_bits = qos_mtt_bits; + + /* get a sir device instance for this driver */ + dev = sirdev_get_instance(&sir_tty_drv, tty->name); + if (!dev) { + ret = -ENODEV; + goto out; + } + + /* allocate private device info block */ + priv = kmalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + goto out_put; + memset(priv, 0, sizeof(*priv)); + + priv->magic = IRTTY_MAGIC; + priv->tty = tty; + priv->dev = dev; + + /* serialize with start_dev - in case we were racing with ifup */ + down(&irtty_sem); + + dev->priv = priv; + tty->disc_data = priv; + + up(&irtty_sem); + + IRDA_DEBUG(0, "%s - %s: irda line discipline opened\n", __FUNCTION__, tty->name); + + return 0; + +out_put: + sirdev_put_instance(dev); +out: + return ret; +} + +/* + * Function irtty_close (tty) + * + * Close down a IrDA channel. This means flushing out any pending queues, + * and then restoring the TTY line discipline to what it was before it got + * hooked to IrDA (which usually is TTY again). + */ +static void irtty_close(struct tty_struct *tty) +{ + struct sirtty_cb *priv = tty->disc_data; + + IRDA_ASSERT(priv != NULL, return;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return;); + + /* Hm, with a dongle attached the dongle driver wants + * to close the dongle - which requires the use of + * some tty write and/or termios or ioctl operations. + * Are we allowed to call those when already requested + * to shutdown the ldisc? + * If not, we should somehow mark the dev being staled. + * Question remains, how to close the dongle in this case... + * For now let's assume we are granted to issue tty driver calls + * until we return here from the ldisc close. I'm just wondering + * how this behaves with hotpluggable serial hardware like + * rs232-pcmcia card or usb-serial... + * + * priv->tty = NULL?; + */ + + /* we are dead now */ + tty->disc_data = NULL; + + sirdev_put_instance(priv->dev); + + /* Stop tty */ + irtty_stop_receiver(tty, TRUE); + tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); + if (tty->driver->stop) + tty->driver->stop(tty); + + kfree(priv); + + IRDA_DEBUG(0, "%s - %s: irda line discipline closed\n", __FUNCTION__, tty->name); +} + +/* ------------------------------------------------------- */ + +static struct tty_ldisc irda_ldisc = { + .magic = TTY_LDISC_MAGIC, + .name = "irda", + .flags = 0, + .open = irtty_open, + .close = irtty_close, + .read = NULL, + .write = NULL, + .ioctl = irtty_ioctl, + .poll = NULL, + .receive_buf = irtty_receive_buf, + .receive_room = irtty_receive_room, + .write_wakeup = irtty_write_wakeup, + .owner = THIS_MODULE, +}; + +/* ------------------------------------------------------- */ + +static int __init irtty_sir_init(void) +{ + int err; + + if ((err = tty_register_ldisc(N_IRDA, &irda_ldisc)) != 0) + IRDA_ERROR("IrDA: can't register line discipline (err = %d)\n", + err); + return err; +} + +static void __exit irtty_sir_cleanup(void) +{ + int err; + + if ((err = tty_register_ldisc(N_IRDA, NULL))) { + IRDA_ERROR("%s(), can't unregister line discipline (err = %d)\n", + __FUNCTION__, err); + } +} + +module_init(irtty_sir_init); +module_exit(irtty_sir_cleanup); + +MODULE_AUTHOR("Dag Brattli "); +MODULE_DESCRIPTION("IrDA TTY device driver"); +MODULE_ALIAS_LDISC(N_IRDA); +MODULE_LICENSE("GPL"); + -- cgit v1.1