* [PATCH], tiser module: TI graphing calculators
@ 2002-03-16 17:19 Romain Liévin
2002-03-16 17:49 ` Alan Cox
0 siblings, 1 reply; 2+ messages in thread
From: Romain Liévin @ 2002-03-16 17:19 UTC (permalink / raw)
To: Kernel List; +Cc: Zwane Mwaikambo, Alan Cox, Theodore T'so
Hi,
This new driver is the brother of tipar. It can handle a serial link
cable
designed to connect a Texas Instruments graphing calculators to a
computer/workstation.
This driver directly accesses some UART registers in a way similar to
serial.c.
A better method should be to do some ioctl for toggling UART lines
rather than by-passing the ttySx driver.
Is there anyone who have some another ideas ?
Romain.
==============================[ cut here ]==============================
--- linux.orig/drivers/char/tiser.c Sat Mar 16 18:16:06 2002
+++ linux/drivers/char/tiser.c Sat Mar 16 18:15:49 2002
@@ -0,0 +1,500 @@
+/* Hey EMACS -*- linux-c -*-
+ *
+ * tiser - low level driver for handling a serial link cable designed
+ * for Texas Instruments graphing calculators (http://lpg.ticalc.org).
+ *
+ * Copyright (C) 2000-2002, Romain Lievin <rlievin@mail.com>
+ * under the terms of the GNU General Public License.
+ *
+ * Fixes v1.12b: Zwane Mwaikambo <zwane@linux.realnet.co.sz>
+ *
+ */
+
+#define TISER_VERSION "1.12b" /* March 2002 */
+
+/* This driver should, in theory, work with any RS232 compliant serial
port.
+ *
+ *
+ *
+ * If this driver is built into the kernel, you can configure it using
the
+ * kernel command-line. For example:
+ *
+ * tiser=timeout,delay (set timeout and delay)
+ *
+ * If the driver is loaded as a module, similar functionality is
available
+ * using module parameters. The equivalent of the above commands would
be:
+ *
+ * # insmod tiser.o tiser=15,10
+ */
+
+/* COMPATIBILITY WITH OLD KERNELS
+ *
+ * Usually, serial cables were bound to ports at
+ * particular I/O addresses, as follows:
+ *
+ * tiser0 0x3f8
+ * tiser1 0x2f8
+ * tiser2 0x3e8
+ * tiser3 0x2e8
+ *
+ * This driver, by default, binds tiser devices according to the minor
number.
+ * This means that if you do not have standard addresses for serial
port,
+ * you will have to manually edit the file and change structure values.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/fcntl.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+#include <linux/ioport.h>
+#include <asm/io.h>
+#include <asm/bitops.h>
+#include <linux/devfs_fs_kernel.h> /* DevFs support */
+#include <linux/serial_reg.h>
+#include <linux/slab.h>
+
+/*
+ * TI definitions
+ */
+#include "ticable.h" //#include <linux/ticable.h>
+
+/* ----- global variables ---------------------------------------------
*/
+
+#define TISER_MODULE_NAME "tiser"
+#define PFX TISER_MODULE_NAME ": "
+
+/*
+ * You must set these - there is no sane way to probe for this link
cable.
+ */
+
+#define SP_NO 4
+/* ports to probe */
+static int serial_ports[SP_NO] = {0x3f8, 0x2f8, 0x3e8, 0x2e8};
+static int tiser_count = 0; /* how many serial ports we have */
+
+static int delay = IO_DELAY; /* inter-bit delay in microseconds
*/
+static int timeout = TIMAXTIME; /* timeout in tenth of seconds
*/
+
+static devfs_handle_t devfs_handle = NULL;
+
+/* per port serial structure, allows per port locking */
+struct tiser_dev_t {
+ int port;
+ int minor;
+ int delay;
+ int timeout;
+ char name[8];
+ spinlock_t lock;
+ struct semaphore open_sem;
+};
+
+static struct tiser_dev_t *tiser_dev[SP_NO];
+
+/* --- setting states on the D-bus with the right timing: -------------
*/
+
+static inline void outbyte(struct tiser_dev_t *dev, int value)
+{
+ spin_lock(&dev->lock);
+ outb(value, dev->port + UART_MCR);
+ spin_unlock(&dev->lock);
+}
+
+static inline int inbyte(struct tiser_dev_t *dev)
+{
+ unsigned char ret;
+ spin_lock(&dev->lock);
+ ret = inb(dev->port + UART_MSR);
+ spin_unlock(&dev->lock);
+ return ret;
+}
+
+static inline void init_ti_serial(struct tiser_dev_t *dev)
+{
+ outbyte(dev, 3);
+}
+
+/* ----- global defines -----------------------------------------------
*/
+
+#define START(x) { max=jiffies+HZ/(timeout/10); }
+#define WAIT(x) \
+do {if (!time_before(jiffies, (x))) \
+return -1; \
+if(current->need_resched) schedule(); \
+} while (0)
+
+/* ----- D-bus bit-banging functions ----------------------------------
*/
+
+/* D-bus protocol (45kbit/s max):
+ 1 0 0
+ _______ ______|______ __________|________
__________
+Red : ________ | ____ | ____
+ _ ____________|________ ______|__________
_____
+White: ________ | ______ | _______
+*/
+
+/* Try to transmit a byte on the specified port (-1 if error). */
+static int put_ti_serial(struct tiser_dev_t *dev, unsigned char data)
+{
+ int bit;
+ unsigned long max;
+
+ for (bit=0; bit<8; bit++) {
+ if (data & 1) {
+ outbyte(dev, 2);
+ START(max);
+ do {
+ WAIT(max);
+ } while(inbyte(dev) & 0x10);
+
+ outbyte(dev, 3);
+ START(max);
+ do {
+ WAIT(max);
+ } while(!(inbyte(dev) & 0x10));
+ } else {
+ outbyte(dev, 1);
+ START(max);
+ do {
+ WAIT(max);
+ } while(inbyte(dev) & 0x20);
+
+ outbyte(dev, 3);
+ START(max);
+ do {
+ WAIT(max);
+ } while(!(inbyte(dev) & 0x20));
+ }
+
+ data >>= 1;
+
+ udelay(delay);
+ if(current->need_resched)
+ schedule();
+ }
+
+ return 0;
+}
+
+/* Receive a byte on the specified port or -1 if error. */
+static int get_ti_serial(struct tiser_dev_t *dev)
+{
+ int bit;
+ unsigned char v, data=0;
+ unsigned long max;
+
+ for (bit=0; bit<8; bit++) {
+ START(max);
+ do {
+ WAIT(max);
+ } while ((v=inbyte(dev) & 0x30) == 0x30);
+
+ if (v == 0x10) {
+ data=(data>>1) | 0x80;
+ outbyte(dev, 1);
+ START(max);
+ do {
+ WAIT(max);
+ } while(!(inbyte(dev) & 0x20));
+ outbyte(dev, 3);
+ } else {
+ data=data>>1;
+ outbyte(dev, 2);
+ START(max);
+ do {
+ WAIT(max);
+ } while(!(inbyte(dev) & 0x10));
+ outbyte(dev, 3);
+ }
+
+ udelay(delay);
+ if(current->need_resched)
+ schedule();
+ }
+
+ return (int)data;
+}
+
+/* Try to detect a parallel link cable on the specified port */
+static inline int probe_ti_serial(struct tiser_dev_t *dev)
+{
+ int i;
+ int seq[]={ 0x00, 0x20, 0x00, 0x30 };
+
+ for(i=3; i>=0; i--) {
+ outbyte(dev, 3);
+ outbyte(dev, i);
+ udelay(delay);
+ /*printk("Probing -> %i: 0x%02x 0x%02x\n", i, data &
0x30, seq[i]);*/
+ if ( (inbyte(dev) & 0x30) != seq[i]) {
+ outbyte(dev, 3);
+ return -1;
+ }
+ }
+
+ outbyte(dev, 3);
+
+ return 0;
+}
+
+/* ----- kernel module functions---------------------------------------
*/
+
+static int tiser_open(struct inode *inode, struct file *file)
+{
+ unsigned int minor = MINOR(inode->i_rdev) - TISER_MINOR_0;
+
+ if (minor >= tiser_count)
+ return -ENXIO;
+
+ if (file->f_flags & O_NONBLOCK) {
+ if (down_trylock (&tiser_dev[minor]->open_sem))
+ return -EAGAIN;
+ } else {
+ if (down_interruptible (&tiser_dev[minor]->open_sem))
+ return -ERESTARTSYS;
+ }
+
+ init_ti_serial(tiser_dev[minor]);
+
+ return 0;
+}
+
+static int tiser_close(struct inode *inode, struct file *file)
+{
+ unsigned int minor = MINOR(inode->i_rdev) - TISER_MINOR_0;
+
+ up(&tiser_dev[minor]->open_sem);
+
+ return 0;
+}
+
+static ssize_t tiser_write(struct file *file, const char *buf, size_t
count, loff_t *ppos)
+{
+ unsigned int minor = MINOR(file->f_dentry->d_inode->i_rdev) -
+ TISER_MINOR_0;
+ ssize_t n;
+
+ if (minor >= tiser_count)
+ return -ENXIO;
+
+ for(n=0; n<count; n++) {
+ unsigned char b;
+
+ if(get_user(b, buf + n))
+ return -EFAULT;
+
+ if(put_ti_serial(tiser_dev[minor], b) == -1) {
+ init_ti_serial(tiser_dev[minor]);
+ return -ETIMEDOUT;
+ }
+ }
+
+ return n;
+}
+
+static ssize_t tiser_read(struct file *file, char *buf, size_t count,
loff_t *ppos)
+{
+ int b=0;
+ unsigned int minor=MINOR(file->f_dentry->d_inode->i_rdev) -
TISER_MINOR_0;
+ ssize_t retval = 0;
+
+ if(count == 0)
+ return 0;
+
+ if(ppos != &file->f_pos)
+ return -ESPIPE;
+
+ do {
+ b = get_ti_serial(tiser_dev[minor]);
+ if(b == -1) {
+ init_ti_serial(tiser_dev[minor]);
+ retval = -ETIMEDOUT;
+ goto out;
+ }
+ else
+ break;
+
+ /* Non-blocking mode : try again ! */
+ if (file->f_flags & O_NONBLOCK) {
+ retval = -EAGAIN;
+ goto out;
+ }
+
+ /* Signal pending, try again ! */
+ if (signal_pending(current)) {
+ retval = -ERESTARTSYS;
+ goto out;
+ }
+
+ if(current->need_resched)
+ schedule();
+ } while (1);
+
+ retval = put_user(b, (unsigned char *)buf);
+ if(!retval)
+ retval = 1;
+ else
+ retval = -EFAULT;
+
+ out:
+ return retval;
+}
+
+static int tiser_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ unsigned int minor = MINOR(inode->i_rdev) - TISER_MINOR_0;
+
+ int retval = 0;
+
+ if (minor >= tiser_count)
+ return -ENODEV;
+
+ switch (cmd) {
+ case TISER_DELAY:
+ tiser_dev[minor]->delay = arg;
+ return 0;
+ case TISER_TIMEOUT:
+ tiser_dev[minor]->timeout = arg;
+ return 0;
+ default:
+ retval = -ENOTTY;
+ break;
+ }
+
+ return retval;
+}
+
+/* ----- kernel module registering ------------------------------------
*/
+
+static struct file_operations tiser_fops = {
+ owner: THIS_MODULE,
+ llseek: no_llseek,
+ read: tiser_read,
+ write: tiser_write,
+ ioctl: tiser_ioctl,
+ open: tiser_open,
+ release: tiser_close,
+};
+
+/* --- initialisation code ------------------------------------- */
+
+#ifndef MODULE
+/* You must set these - there is no sane way to probe for this
board.
+ * You can use tiser=timeout,delay to set these now. */
+static int __init tiser_setup (char *str)
+{
+ int ints[2];
+
+ str = get_options (str, ARRAY_SIZE(ints), ints);
+
+ if (ints[0] > 0) {
+ timeout = ints[1];
+ if(ints[0] > 1) {
+ delay = ints[2];
+ }
+ }
+ return 1;
+}
+#endif
+
+int __init tiser_init_module(void)
+{
+ char name[8];
+ int nr;
+
+ printk(KERN_INFO PFX "serial link cable driver, version %s\n",
TISER_VERSION);
+
+ if (devfs_register_chrdev(TISER_MAJOR, TISER_MODULE_NAME,
&tiser_fops)) {
+ printk(KERN_ERR PFX "unable to get major %d\n",
TISER_MAJOR);
+ return -EIO;
+ }
+
+ for (nr=0; nr<SP_NO; nr++) {
+ /*
+ if (!request_region(serial_ports[nr], 8,
TISER_MODULE_NAME)) {
+ printk(KERN_ERR PFX "unable to register port %#x\n",
serial_ports[nr]);
+ continue;
+ }*/
+
+ /* allocate and init our device structure */
+ tiser_dev[tiser_count] = kmalloc(sizeof (struct
tiser_dev_t), GFP_KERNEL);
+
+ if (tiser_dev[tiser_count] == NULL) {
+ printk(KERN_ERR PFX "unable to kmalloc
(OOM?)\n");
+ continue;
+ }
+
+ sema_init(&tiser_dev[tiser_count]->open_sem, 1);
+ spin_lock_init(&tiser_dev[tiser_count]->lock);
+ tiser_dev[tiser_count]->port = serial_ports[nr];
+ tiser_dev[tiser_count]->minor = tiser_count;
+ tiser_dev[tiser_count]->delay = delay;
+ tiser_dev[tiser_count]->timeout = timeout;
+ sprintf(tiser_dev[tiser_count]->name, "tiser%d", nr);
+ tiser_count++;
+ }
+
+ if (!tiser_count)
+ goto out_devfs;
+
+ for(nr=0; nr<tiser_count; nr++) {
+ sprintf(name, "%d", nr);
+ devfs_register(devfs_handle, name,
+ DEVFS_FL_DEFAULT, TISER_MAJOR, nr,
+ S_IFCHR | S_IRUGO | S_IWUGO,
+ &tiser_fops, NULL);
+ }
+
+ for(nr=0; nr<SP_NO; nr++) {
+ if(probe_ti_serial(tiser_dev[nr]) != -1)
+ printk(KERN_INFO "%s: link cable found !\n",
tiser_dev[nr]->name);
+ else
+ printk(KERN_INFO "%s: link cable not found (did
you plug the cable to calc ?).\n", tiser_dev[nr]->name);
+ }
+
+ return 0;
+
+ out_devfs:
+ devfs_unregister_chrdev(TISER_MAJOR, TISER_MODULE_NAME);
+ return -1;
+}
+
+void __exit tiser_cleanup_module(void)
+{
+ int i;
+
+ devfs_unregister(devfs_handle);
+ devfs_unregister_chrdev(TISER_MAJOR, TISER_MODULE_NAME);
+
+ for(i=0; i<tiser_count; i++) {
+ //release_region(tiser_dev[i]->port, 8);
+ kfree(tiser_dev[i]);
+ }
+
+ printk(KERN_DEBUG PFX "module unloaded.\n");
+}
+
+__setup("tiser=", tiser_setup);
+module_init(tiser_init_module);
+module_exit(tiser_cleanup_module);
+
+MODULE_AUTHOR("Author/Maintainer: Romain Lievin
<rosm@lpg.ticalc.org>");
+MODULE_DESCRIPTION("Device driver for TI/PC serial link cables");
+MODULE_LICENSE("GPL");
+
+EXPORT_NO_SYMBOLS;
+
+MODULE_PARM(timeout, "i");
+MODULE_PARM_DESC(timeout, "Timeout (default=1.5 seconds)");
+MODULE_PARM(delay, "i");
+MODULE_PARM_DESC(delay, "Inter-bit delay (default=10 microseconds)");
+
+
--- linux.orig/include/linux/ticable.h Sat Mar 16 15:35:35 2002
+++ linux/include/linux/ticable.h Sat Mar 16 15:37:43 2002
@@ -0,0 +1,41 @@
+/* Hey EMACS -*- linux-c -*-
+ *
+ * tipar/tiser/tiglusb - low level driver for handling link cables
+ * designed for Texas Instruments graphing calculators.
+ *
+ * Copyright (C) 2000-2002, Romain Lievin <roms@lpg.ticalc.org>
+ * under the terms of the GNU General Public License.
+ */
+
+#ifndef TICABLE_H
+#define TICABLE_H 1
+
+/* Internal default constants for the kernel module */
+#define TIMAXTIME 10 /* 1 seconds */
+#define IO_DELAY 10 /* 10 micro-seconds */
+
+/* Major & minor number for character devices */
+#define TIPAR_MAJOR 61
+#define TIPAR_MINOR_0 1
+#define TIPAR_MINOR_1 2
+#define TIPAR_MINOR_2 3
+
+#define TISER_MAJOR 62
+#define TISER_MINOR_0 1
+#define TISER_MINOR_1 2
+#define TISER_MINOR_2 3
+#define TISER_MINOR_3 4
+
+/*
+ * Request values for the 'ioctl' function.
+ * Simply pass the appropriate value as arg of the ioctl call.
+ * These values do not conflict with other ones but they have to be
+ * allocated... (/usr/src/linux/Documentation/ioctl-number.txt).
+ */
+#define TIPAR_DELAY _IOW('p', 0xa8, int) /* set delay */
+#define TIPAR_TIMEOUT _IOW('p', 0xa9, int) /* set timeout */
+
+#define TISER_DELAY _IOW('p', 0xa0, int) /* set delay */
+#define TISER_TIMEOUT _IOW('p', 0xa1, int) /* set timeout */
+
+#endif /* TICABLE_H */
--
Romain LIEVIN aka Roms, mail: roms@lpg.ticalc.org
web: http://lpg.ticalc.org/prj_tilp (on www.ticalc.org)
ICQ: 43585029 (GtkIcq0.60/Linux)
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2002-03-16 17:19 [PATCH], tiser module: TI graphing calculators Romain Liévin
2002-03-16 17:49 ` Alan Cox
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