--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/tty/module.c Mon Jan 04 11:28:29 2010 +0100
@@ -0,0 +1,696 @@
+/******************************************************************************
+ *
+ * $Id$
+ *
+ * Copyright (C) 2006-2008 Florian Pose, Ingenieurgemeinschaft IgH
+ *
+ * This file is part of the IgH EtherCAT Master.
+ *
+ * The IgH EtherCAT Master is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * The IgH EtherCAT Master 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 the IgH EtherCAT Master; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * ---
+ *
+ * The license mentioned above concerns the source code only. Using the
+ * EtherCAT technology and brand is only permitted in compliance with the
+ * industrial property and similar rights of Beckhoff Automation GmbH.
+ *
+ *****************************************************************************/
+
+/** \file
+ * EtherCAT tty driver module.
+ */
+
+/*****************************************************************************/
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/termios.h>
+#include <linux/timer.h>
+
+#include "../master/globals.h"
+#include "../include/ectty.h"
+
+/*****************************************************************************/
+
+#define PFX "ec_tty: "
+
+#define EC_TTY_MAX_DEVICES 10
+#define EC_TTY_TX_BUFFER_SIZE 100
+#define EC_TTY_RX_BUFFER_SIZE 100
+
+#define EC_TTY_DEBUG 0
+
+/*****************************************************************************/
+
+char *ec_master_version_str = EC_MASTER_VERSION; /**< Version string. */
+unsigned int debug_level = 0;
+
+static struct tty_driver *tty_driver = NULL;
+ec_tty_t *ttys[EC_TTY_MAX_DEVICES];
+struct semaphore tty_sem;
+
+/*****************************************************************************/
+
+/** \cond */
+
+MODULE_AUTHOR("Florian Pose <fp@igh-essen.com>");
+MODULE_DESCRIPTION("EtherCAT TTY driver module");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(EC_MASTER_VERSION);
+
+module_param_named(debug_level, debug_level, uint, S_IRUGO);
+MODULE_PARM_DESC(debug_level, "Debug level");
+
+/** \endcond */
+
+static struct ktermios ec_tty_std_termios = {
+ .c_iflag = ICRNL | IXON,
+ .c_oflag = OPOST,
+ .c_cflag = B38400 | CS8 | CREAD | HUPCL,
+ .c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN,
+ .c_cc = INIT_C_CC,
+};
+
+struct ec_tty {
+ int minor;
+ struct device *dev;
+
+ uint8_t tx_buffer[EC_TTY_TX_BUFFER_SIZE];
+ unsigned int tx_read_idx;
+ unsigned int tx_write_idx;
+ unsigned int wakeup;
+
+ uint8_t rx_buffer[EC_TTY_RX_BUFFER_SIZE];
+ unsigned int rx_read_idx;
+ unsigned int rx_write_idx;
+
+ struct timer_list timer;
+ struct tty_struct *tty;
+};
+
+static const struct tty_operations ec_tty_ops; // see below
+
+/*****************************************************************************/
+
+/** Module initialization.
+ *
+ * \return 0 on success, else < 0
+ */
+int __init ec_tty_init_module(void)
+{
+ int i, ret = 0;
+
+ printk(KERN_INFO PFX "TTY driver %s\n", EC_MASTER_VERSION);
+
+ init_MUTEX(&tty_sem);
+
+ for (i = 0; i < EC_TTY_MAX_DEVICES; i++) {
+ ttys[i] = NULL;
+ }
+
+ tty_driver = alloc_tty_driver(EC_TTY_MAX_DEVICES);
+ if (!tty_driver) {
+ printk(KERN_ERR PFX "Failed to allocate tty driver.\n");
+ ret = -ENOMEM;
+ goto out_return;
+ }
+
+ tty_driver->owner = THIS_MODULE;
+ tty_driver->driver_name = "EtherCAT TTY";
+ tty_driver->name = "ttyEC";
+ tty_driver->major = 0;
+ tty_driver->minor_start = 0;
+ tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
+ tty_driver->subtype = SERIAL_TYPE_NORMAL;
+ tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
+ tty_driver->init_termios = ec_tty_std_termios;
+ tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+ tty_set_operations(tty_driver, &ec_tty_ops);
+
+ ret = tty_register_driver(tty_driver);
+ if (ret) {
+ printk(KERN_ERR PFX "Failed to register tty driver.\n");
+ goto out_put;
+ }
+
+ return ret;
+
+out_put:
+ put_tty_driver(tty_driver);
+out_return:
+ return ret;
+}
+
+/*****************************************************************************/
+
+/** Module cleanup.
+ *
+ * Clears all master instances.
+ */
+void __exit ec_tty_cleanup_module(void)
+{
+ tty_unregister_driver(tty_driver);
+ put_tty_driver(tty_driver);
+ printk(KERN_INFO PFX "Module unloading.\n");
+}
+
+/*****************************************************************************/
+
+unsigned int ec_tty_tx_size(ec_tty_t *tty)
+{
+ unsigned int ret;
+
+ if (tty->tx_write_idx >= tty->tx_read_idx) {
+ ret = tty->tx_write_idx - tty->tx_read_idx;
+ } else {
+ ret = EC_TTY_TX_BUFFER_SIZE + tty->tx_write_idx - tty->tx_read_idx;
+ }
+
+ return ret;
+}
+
+/*****************************************************************************/
+
+unsigned int ec_tty_tx_space(ec_tty_t *tty)
+{
+ return EC_TTY_TX_BUFFER_SIZE - 1 - ec_tty_tx_size(tty);
+}
+
+/*****************************************************************************/
+
+unsigned int ec_tty_rx_size(ec_tty_t *tty)
+{
+ unsigned int ret;
+
+ if (tty->rx_write_idx >= tty->rx_read_idx) {
+ ret = tty->rx_write_idx - tty->rx_read_idx;
+ } else {
+ ret = EC_TTY_RX_BUFFER_SIZE + tty->rx_write_idx - tty->rx_read_idx;
+ }
+
+ return ret;
+}
+
+/*****************************************************************************/
+
+unsigned int ec_tty_rx_space(ec_tty_t *tty)
+{
+ return EC_TTY_RX_BUFFER_SIZE - 1 - ec_tty_rx_size(tty);
+}
+
+/*****************************************************************************/
+
+void ec_tty_wakeup(unsigned long data)
+{
+ ec_tty_t *tty = (ec_tty_t *) data;
+ size_t to_recv;
+
+ /* Wake up any process waiting to send data */
+ if (tty->wakeup) {
+ if (tty->tty) {
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "Waking up.\n");
+#endif
+ tty_wakeup(tty->tty);
+ }
+ tty->wakeup = 0;
+ }
+
+ /* Push received data into TTY core. */
+ to_recv = ec_tty_rx_size(tty);
+ if (to_recv && tty->tty) {
+ unsigned char *cbuf;
+ int space = tty_prepare_flip_string(tty->tty, &cbuf, to_recv);
+
+ if (space < to_recv) {
+ printk(KERN_WARNING PFX "Insufficient space to_recv=%d space=%d\n",
+ to_recv, space);
+ }
+
+ if (space < 0) {
+ to_recv = 0;
+ } else {
+ to_recv = space;
+ }
+
+ if (to_recv) {
+ unsigned int i;
+
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "Pushing %u bytes to TTY core.\n", to_recv);
+#endif
+
+ for (i = 0; i < to_recv; i++) {
+ cbuf[i] = tty->rx_buffer[tty->rx_read_idx];
+ tty->rx_read_idx = (tty->rx_read_idx + 1) % EC_TTY_RX_BUFFER_SIZE;
+ }
+ tty_flip_buffer_push(tty->tty);
+ }
+ }
+
+ tty->timer.expires += 1;
+ add_timer(&tty->timer);
+}
+
+/*****************************************************************************/
+
+int ec_tty_init(ec_tty_t *tty, int minor)
+{
+ tty->minor = minor;
+ tty->tx_read_idx = 0;
+ tty->tx_write_idx = 0;
+ tty->wakeup = 0;
+ tty->rx_read_idx = 0;
+ tty->rx_write_idx = 0;
+ init_timer(&tty->timer);
+ tty->tty = NULL;
+
+ tty->dev = tty_register_device(tty_driver, tty->minor, NULL);
+ if (IS_ERR(tty->dev)) {
+ printk(KERN_ERR PFX "Failed to register tty device.\n");
+ return PTR_ERR(tty->dev);
+ }
+
+ tty->timer.function = ec_tty_wakeup;
+ tty->timer.data = (unsigned long) tty;
+ tty->timer.expires = jiffies + 10;
+ add_timer(&tty->timer);
+ return 0;
+}
+
+/*****************************************************************************/
+
+void ec_tty_clear(ec_tty_t *tty)
+{
+ del_timer_sync(&tty->timer);
+ tty_unregister_device(tty_driver, tty->minor);
+}
+
+/******************************************************************************
+ * Device callbacks
+ *****************************************************************************/
+
+static int ec_tty_open(struct tty_struct *tty, struct file *file)
+{
+ ec_tty_t *t;
+ int line = tty->index;
+
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "Opening line %i.\n", line);
+#endif
+
+ if (line < 0 || line >= EC_TTY_MAX_DEVICES) {
+ return -ENXIO;
+ }
+
+ t = ttys[line];
+ if (!t) {
+ return -ENXIO;
+ }
+
+ if (t->tty) {
+ return -EBUSY;
+ }
+
+ t->tty = tty;
+ tty->driver_data = t;
+ return 0;
+}
+
+/*****************************************************************************/
+
+static void ec_tty_close(struct tty_struct *tty, struct file *file)
+{
+ ec_tty_t *t = (ec_tty_t *) tty->driver_data;
+
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "Closing line %i.\n", tty->index);
+#endif
+
+ if (t->tty == tty) {
+ t->tty = NULL;
+ }
+}
+
+/*****************************************************************************/
+
+static int ec_tty_write(
+ struct tty_struct *tty,
+ const unsigned char *buffer,
+ int count
+ )
+{
+ ec_tty_t *t = (ec_tty_t *) tty->driver_data;
+ unsigned int data_size, i;
+
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "%s(count=%i)\n", __func__, count);
+#endif
+
+ if (count <= 0) {
+ return 0;
+ }
+
+ data_size = min(ec_tty_tx_space(t), (unsigned int) count);
+ for (i = 0; i < data_size; i++) {
+ t->tx_buffer[t->tx_write_idx] = buffer[i];
+ t->tx_write_idx = (t->tx_write_idx + 1) % EC_TTY_TX_BUFFER_SIZE;
+ }
+
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "%s(): %u bytes written.\n", __func__, data_size);
+#endif
+ return data_size;
+}
+
+/*****************************************************************************/
+
+static void ec_tty_put_char(struct tty_struct *tty, unsigned char ch)
+{
+ ec_tty_t *t = (ec_tty_t *) tty->driver_data;
+
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "%s(): c=%02x.\n", __func__, (unsigned int) ch);
+#endif
+
+ if (ec_tty_tx_space(t)) {
+ t->tx_buffer[t->tx_write_idx] = ch;
+ t->tx_write_idx = (t->tx_write_idx + 1) % EC_TTY_TX_BUFFER_SIZE;
+ } else {
+ printk(KERN_WARNING PFX "%s(): Dropped a byte!\n", __func__);
+ }
+}
+
+/*****************************************************************************/
+
+static int ec_tty_write_room(struct tty_struct *tty)
+{
+ ec_tty_t *t = (ec_tty_t *) tty->driver_data;
+ int ret = ec_tty_tx_space(t);
+
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s() = %i.\n", __func__, ret);
+#endif
+
+ return ret;
+}
+
+/*****************************************************************************/
+
+static int ec_tty_chars_in_buffer(struct tty_struct *tty)
+{
+ ec_tty_t *t = (ec_tty_t *) tty->driver_data;
+ int ret;
+
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+
+ ret = ec_tty_tx_size(t);
+
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s() = %i.\n", __func__, ret);
+#endif
+
+ return ret;
+}
+
+/*****************************************************************************/
+
+static void ec_tty_flush_buffer(struct tty_struct *tty)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+}
+
+/*****************************************************************************/
+
+static int ec_tty_ioctl(struct tty_struct *tty, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+ return -ENOTTY;
+}
+
+/*****************************************************************************/
+
+static void ec_tty_throttle(struct tty_struct *tty)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+}
+
+/*****************************************************************************/
+
+static void ec_tty_unthrottle(struct tty_struct *tty)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+}
+
+/*****************************************************************************/
+
+static void ec_tty_set_termios(struct tty_struct *tty,
+ struct ktermios *old_termios)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+}
+
+/*****************************************************************************/
+
+static void ec_tty_stop(struct tty_struct *tty)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+}
+
+/*****************************************************************************/
+
+static void ec_tty_start(struct tty_struct *tty)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+}
+
+/*****************************************************************************/
+
+static void ec_tty_hangup(struct tty_struct *tty)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+}
+
+/*****************************************************************************/
+
+static void ec_tty_break(struct tty_struct *tty, int break_state)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s(break_state = %i).\n", __func__, break_state);
+#endif
+}
+
+/*****************************************************************************/
+
+static void ec_tty_send_xchar(struct tty_struct *tty, char ch)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s(ch=%02x).\n", __func__, (unsigned int) ch);
+#endif
+}
+
+/*****************************************************************************/
+
+static void ec_tty_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s(timeout=%i).\n", __func__, timeout);
+#endif
+}
+
+/*****************************************************************************/
+
+static int ec_tty_tiocmget(struct tty_struct *tty, struct file *file)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s().\n", __func__);
+#endif
+ return -EBUSY;
+}
+
+/*****************************************************************************/
+
+static int ec_tty_tiocmset(struct tty_struct *tty, struct file *file,
+ unsigned int set, unsigned int clear)
+{
+#if EC_TTY_DEBUG >= 2
+ printk(KERN_INFO PFX "%s(set=%u, clear=%u).\n", __func__, set, clear);
+#endif
+ return -EBUSY;
+}
+
+/*****************************************************************************/
+
+static const struct tty_operations ec_tty_ops = {
+ .open = ec_tty_open,
+ .close = ec_tty_close,
+ .write = ec_tty_write,
+ .put_char = ec_tty_put_char,
+ .write_room = ec_tty_write_room,
+ .chars_in_buffer = ec_tty_chars_in_buffer,
+ .flush_buffer = ec_tty_flush_buffer,
+ .ioctl = ec_tty_ioctl,
+ .throttle = ec_tty_throttle,
+ .unthrottle = ec_tty_unthrottle,
+ .set_termios = ec_tty_set_termios,
+ .stop = ec_tty_stop,
+ .start = ec_tty_start,
+ .hangup = ec_tty_hangup,
+ .break_ctl = ec_tty_break,
+ .send_xchar = ec_tty_send_xchar,
+ .wait_until_sent = ec_tty_wait_until_sent,
+ .tiocmget = ec_tty_tiocmget,
+ .tiocmset = ec_tty_tiocmset,
+};
+
+/******************************************************************************
+ * Public functions and methods
+ *****************************************************************************/
+
+ec_tty_t *ectty_create(void)
+{
+ ec_tty_t *tty;
+ int minor, ret;
+
+ if (down_interruptible(&tty_sem)) {
+ return ERR_PTR(-EINTR);
+ }
+
+ for (minor = 0; minor < EC_TTY_MAX_DEVICES; minor++) {
+ if (!ttys[minor]) {
+ printk(KERN_INFO PFX "Creating TTY interface %i.\n", minor);
+
+ tty = kmalloc(sizeof(ec_tty_t), GFP_KERNEL);
+ if (!tty) {
+ up(&tty_sem);
+ printk(KERN_ERR PFX "Failed to allocate memory.\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ ret = ec_tty_init(tty, minor);
+ if (ret) {
+ up(&tty_sem);
+ kfree(tty);
+ return ERR_PTR(ret);
+ }
+
+ ttys[minor] = tty;
+ up(&tty_sem);
+ return tty;
+ }
+ }
+
+ up(&tty_sem);
+ printk(KERN_ERR PFX "No free interfaces avaliable.\n");
+ return ERR_PTR(-EBUSY);
+}
+
+/*****************************************************************************/
+
+void ectty_free(ec_tty_t *tty)
+{
+ printk(KERN_INFO PFX "Freeing TTY interface %i.\n", tty->minor);
+
+ ec_tty_clear(tty);
+ ttys[tty->minor] = NULL;
+ kfree(tty);
+}
+
+/*****************************************************************************/
+
+unsigned int ectty_tx_data(ec_tty_t *tty, uint8_t *buffer, size_t size)
+{
+ unsigned int data_size = min(ec_tty_tx_size(tty), size), i;
+
+ if (data_size) {
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "Fetching %u bytes to send.\n", data_size);
+#endif
+ }
+
+ for (i = 0; i < data_size; i++) {
+ buffer[i] = tty->tx_buffer[tty->tx_read_idx];
+ tty->tx_read_idx = (tty->tx_read_idx + 1) % EC_TTY_TX_BUFFER_SIZE;
+ }
+
+ if (data_size) {
+ tty->wakeup = 1;
+ }
+
+ return data_size;
+}
+
+/*****************************************************************************/
+
+void ectty_rx_data(ec_tty_t *tty, const uint8_t *buffer, size_t size)
+{
+ size_t to_recv;
+
+ if (size) {
+ unsigned int i;
+
+#if EC_TTY_DEBUG >= 1
+ printk(KERN_INFO PFX "Received %u bytes.\n", size);
+#endif
+
+ to_recv = min(ec_tty_rx_space(tty), size);
+
+ if (to_recv < size) {
+ printk(KERN_WARNING PFX "Dropping %u bytes.\n", size - to_recv);
+ }
+
+ for (i = 0; i < size; i++) {
+ tty->rx_buffer[tty->rx_write_idx] = buffer[i];
+ tty->rx_write_idx = (tty->rx_write_idx + 1) % EC_TTY_RX_BUFFER_SIZE;
+ }
+ }
+}
+
+/*****************************************************************************/
+
+/** \cond */
+
+module_init(ec_tty_init_module);
+module_exit(ec_tty_cleanup_module);
+
+EXPORT_SYMBOL(ectty_create);
+EXPORT_SYMBOL(ectty_free);
+EXPORT_SYMBOL(ectty_tx_data);
+EXPORT_SYMBOL(ectty_rx_data);
+
+/** \endcond */
+
+/*****************************************************************************/