drivers/usb/serial/omninet.c

   1 /*
   2  * USB ZyXEL omni.net LCD PLUS driver
   3  *
   4  *      This program is free software; you can redistribute it and/or modify
   5  *      it under the terms of the GNU General Public License as published by
   6  *      the Free Software Foundation; either version 2 of the License, or
   7  *      (at your option) any later version.
   8  *
   9  * See Documentation/usb/usb-serial.txt for more information on using this driver
  10  *
  11  * Please report both successes and troubles to the author at omninet@kroah.com
  12  *
  13  * (05/30/2001) gkh
  14  *      switched from using spinlock to a semaphore, which fixes lots of problems.
  15  *
  16  * (04/08/2001) gb
  17  *      Identify version on module load.
  18  *
  19  * (11/01/2000) Adam J. Richter
  20  *      usb_device_id table support
  21  *
  22  * (10/05/2000) gkh
  23  *      Fixed bug with urb->dev not being set properly, now that the usb
  24  *      core needs it.
  25  *
  26  * (08/28/2000) gkh
  27  *      Added locks for SMP safeness.
  28  *      Fixed MOD_INC and MOD_DEC logic and the ability to open a port more
  29  *      than once.
  30  *      Fixed potential race in omninet_write_bulk_callback
  31  *
  32  * (07/19/2000) gkh
  33  *      Added module_init and module_exit functions to handle the fact that this
  34  *      driver is a loadable module now.
  35  *
  36  */
  37
  38 #include <linux/kernel.h>
  39 #include <linux/errno.h>
  40 #include <linux/init.h>
  41 #include <linux/slab.h>
  42 #include <linux/tty.h>
  43 #include <linux/tty_driver.h>
  44 #include <linux/tty_flip.h>
  45 #include <linux/module.h>
  46 #include <linux/spinlock.h>
  47 #include <asm/uaccess.h>
  48 #include <linux/usb.h>
  49 #include "usb-serial.h"
  50
  51 static int debug;
  52
  53 /*
  54  * Version Information
  55  */
  56 #define DRIVER_VERSION "v1.1"
  57 #define DRIVER_AUTHOR "Alessandro Zummo"
  58 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
  59
  60 #define ZYXEL_VENDOR_ID         0x0586
  61 #define ZYXEL_OMNINET_ID        0x1000
  62 #define BT_IGNITIONPRO_ID       0x2000  /* This one seems to be a re-branded ZyXEL device */
  63
  64 /* function prototypes */
  65 static int  omninet_open                (struct usb_serial_port *port, struct file *filp);
  66 static void omninet_close               (struct usb_serial_port *port, struct file *filp);
  67 static void omninet_read_bulk_callback  (struct urb *urb, struct pt_regs *regs);
  68 static void omninet_write_bulk_callback (struct urb *urb, struct pt_regs *regs);
  69 static int  omninet_write               (struct usb_serial_port *port, const unsigned char *buf, int count);
  70 static int  omninet_write_room          (struct usb_serial_port *port);
  71 static void omninet_shutdown            (struct usb_serial *serial);
  72
  73 static struct usb_device_id id_table [] = {
  74         { USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
  75         { USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
  76         { }                                             /* Terminating entry */
  77 };
  78
  79 MODULE_DEVICE_TABLE (usb, id_table);
  80
  81 static struct usb_driver omninet_driver = {
  82         .name =         "omninet",
  83         .probe =        usb_serial_probe,
  84         .disconnect =   usb_serial_disconnect,
  85         .id_table =     id_table,
  86         .no_dynamic_id =        1,
  87 };
  88
  89
  90 static struct usb_serial_driver zyxel_omninet_device = {
  91         .driver = {
  92                 .owner =        THIS_MODULE,
  93                 .name =         "omninet",
  94         },
  95         .description =          "ZyXEL - omni.net lcd plus usb",
  96         .id_table =             id_table,
  97         .num_interrupt_in =     1,
  98         .num_bulk_in =          1,
  99         .num_bulk_out =         2,
 100         .num_ports =            1,
 101         .open =                 omninet_open,
 102         .close =                omninet_close,
 103         .write =                omninet_write,
 104         .write_room =           omninet_write_room,
 105         .read_bulk_callback =   omninet_read_bulk_callback,
 106         .write_bulk_callback =  omninet_write_bulk_callback,
 107         .shutdown =             omninet_shutdown,
 108 };
 109
 110
 111 /* The protocol.
 112  *
 113  * The omni.net always exchange 64 bytes of data with the host. The first
 114  * four bytes are the control header, you can see it in the above structure.
 115  *
 116  * oh_seq is a sequence number. Don't know if/how it's used.
 117  * oh_len is the length of the data bytes in the packet.
 118  * oh_xxx Bit-mapped, related to handshaking and status info.
 119  *      I normally set it to 0x03 in trasmitted frames.
 120  *      7: Active when the TA is in a CONNECTed state.
 121  *      6: unknown
 122  *      5: handshaking, unknown
 123  *      4: handshaking, unknown
 124  *      3: unknown, usually 0
 125  *      2: unknown, usually 0
 126  *      1: handshaking, unknown, usually set to 1 in trasmitted frames
 127  *      0: handshaking, unknown, usually set to 1 in trasmitted frames
 128  * oh_pad Probably a pad byte.
 129  *
 130  * After the header you will find data bytes if oh_len was greater than zero.
 131  *
 132  */
 133
 134 struct omninet_header
 135 {
 136         __u8    oh_seq;
 137         __u8    oh_len;
 138         __u8    oh_xxx;
 139         __u8    oh_pad;
 140 };
 141
 142 struct omninet_data
 143 {
 144         __u8    od_outseq;      // Sequence number for bulk_out URBs
 145 };
 146
 147 static int omninet_open (struct usb_serial_port *port, struct file *filp)
 148 {
 149         struct usb_serial       *serial = port->serial;
 150         struct usb_serial_port  *wport;
 151         struct omninet_data     *od;
 152         int                     result = 0;
 153
 154         dbg("%s - port %d", __FUNCTION__, port->number);
 155
 156         od = kmalloc( sizeof(struct omninet_data), GFP_KERNEL );
 157         if( !od ) {
 158                 err("%s- kmalloc(%Zd) failed.", __FUNCTION__, sizeof(struct omninet_data));
 159                 return -ENOMEM;
 160         }
 161
 162         usb_set_serial_port_data(port, od);
 163         wport = serial->port[1];
 164         wport->tty = port->tty;
 165
 166         /* Start reading from the device */
 167         usb_fill_bulk_urb(port->read_urb, serial->dev,
 168                       usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
 169                       port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
 170                       omninet_read_bulk_callback, port);
 171         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 172         if (result)
 173                 err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
 174
 175         return result;
 176 }
 177
 178 static void omninet_close (struct usb_serial_port *port, struct file * filp)
 179 {
 180         struct usb_serial       *serial = port->serial;
 181         struct usb_serial_port  *wport;
 182
 183         dbg("%s - port %d", __FUNCTION__, port->number);
 184
 185         wport = serial->port[1];
 186         usb_kill_urb(wport->write_urb);
 187         usb_kill_urb(port->read_urb);
 188
 189         kfree(usb_get_serial_port_data(port));
 190 }
 191
 192
 193 #define OMNINET_DATAOFFSET      0x04
 194 #define OMNINET_HEADERLEN       sizeof(struct omninet_header)
 195 #define OMNINET_BULKOUTSIZE     (64 - OMNINET_HEADERLEN)
 196
 197 static void omninet_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 198 {
 199         struct usb_serial_port  *port   = (struct usb_serial_port *)urb->context;
 200         unsigned char           *data   = urb->transfer_buffer;
 201         struct omninet_header   *header = (struct omninet_header *) &data[0];
 202
 203         int i;
 204         int result;
 205
 206         dbg("%s - port %d", __FUNCTION__, port->number);
 207
 208         if (urb->status) {
 209                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
 210                 return;
 211         }
 212
 213         if ((debug) && (header->oh_xxx != 0x30)) {
 214                 if (urb->actual_length) {
 215                         printk (KERN_DEBUG __FILE__ ": omninet_read %d: ", header->oh_len);
 216                         for (i = 0; i < (header->oh_len + OMNINET_HEADERLEN); i++) {
 217                                 printk ("%.2x ", data[i]);
 218                         }
 219                         printk ("\n");
 220                 }
 221         }
 222
 223         if (urb->actual_length && header->oh_len) {
 224                 for (i = 0; i < header->oh_len; i++) {
 225                          tty_insert_flip_char(port->tty, data[OMNINET_DATAOFFSET + i], 0);
 226                 }
 227                 tty_flip_buffer_push(port->tty);
 228         }
 229
 230         /* Continue trying to always read  */
 231         usb_fill_bulk_urb(urb, port->serial->dev,
 232                       usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
 233                       urb->transfer_buffer, urb->transfer_buffer_length,
 234                       omninet_read_bulk_callback, port);
 235         result = usb_submit_urb(urb, GFP_ATOMIC);
 236         if (result)
 237                 err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
 238
 239         return;
 240 }
 241
 242 static int omninet_write (struct usb_serial_port *port, const unsigned char *buf, int count)
 243 {
 244         struct usb_serial       *serial = port->serial;
 245         struct usb_serial_port  *wport  = serial->port[1];
 246
 247         struct omninet_data     *od     = usb_get_serial_port_data(port);
 248         struct omninet_header   *header = (struct omninet_header *) wport->write_urb->transfer_buffer;
 249
 250         int                     result;
 251
 252         dbg("%s - port %d", __FUNCTION__, port->number);
 253
 254         if (count == 0) {
 255                 dbg("%s - write request of 0 bytes", __FUNCTION__);
 256                 return (0);
 257         }
 258
 259         spin_lock(&wport->lock);
 260         if (wport->write_urb_busy) {
 261                 spin_unlock(&wport->lock);
 262                 dbg("%s - already writing", __FUNCTION__);
 263                 return 0;
 264         }
 265         wport->write_urb_busy = 1;
 266         spin_unlock(&wport->lock);
 267
 268         count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
 269
 270         memcpy (wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET, buf, count);
 271
 272         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, wport->write_urb->transfer_buffer);
 273
 274         header->oh_seq  = od->od_outseq++;
 275         header->oh_len  = count;
 276         header->oh_xxx  = 0x03;
 277         header->oh_pad  = 0x00;
 278
 279         /* send the data out the bulk port, always 64 bytes */
 280         wport->write_urb->transfer_buffer_length = 64;
 281
 282         wport->write_urb->dev = serial->dev;
 283         result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
 284         if (result) {
 285                 wport->write_urb_busy = 0;
 286                 err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
 287         } else
 288                 result = count;
 289
 290         return result;
 291 }
 292
 293
 294 static int omninet_write_room (struct usb_serial_port *port)
 295 {
 296         struct usb_serial       *serial = port->serial;
 297         struct usb_serial_port  *wport  = serial->port[1];
 298
 299         int room = 0; // Default: no room
 300
 301         if (wport->write_urb_busy)
 302                 room = wport->bulk_out_size - OMNINET_HEADERLEN;
 303
 304         dbg("%s - returns %d", __FUNCTION__, room);
 305
 306         return (room);
 307 }
 308
 309 static void omninet_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 310 {
 311 /*      struct omninet_header   *header = (struct omninet_header  *) urb->transfer_buffer; */
 312         struct usb_serial_port  *port   = (struct usb_serial_port *) urb->context;
 313
 314         dbg("%s - port %0x\n", __FUNCTION__, port->number);
 315
 316         port->write_urb_busy = 0;
 317         if (urb->status) {
 318                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 319                 return;
 320         }
 321
 322         usb_serial_port_softint(port);
 323 }
 324
 325
 326 static void omninet_shutdown (struct usb_serial *serial)
 327 {
 328         dbg ("%s", __FUNCTION__);
 329 }
 330
 331
 332 static int __init omninet_init (void)
 333 {
 334         int retval;
 335         retval = usb_serial_register(&zyxel_omninet_device);
 336         if (retval)
 337                 goto failed_usb_serial_register;
 338         retval = usb_register(&omninet_driver);
 339         if (retval)
 340                 goto failed_usb_register;
 341         info(DRIVER_VERSION ":" DRIVER_DESC);
 342         return 0;
 343 failed_usb_register:
 344         usb_serial_deregister(&zyxel_omninet_device);
 345 failed_usb_serial_register:
 346         return retval;
 347 }
 348
 349
 350 static void __exit omninet_exit (void)
 351 {
 352         usb_deregister (&omninet_driver);
 353         usb_serial_deregister (&zyxel_omninet_device);
 354 }
 355
 356
 357 module_init(omninet_init);
 358 module_exit(omninet_exit);
 359
 360 MODULE_AUTHOR( DRIVER_AUTHOR );
 361 MODULE_DESCRIPTION( DRIVER_DESC );
 362 MODULE_LICENSE("GPL");
 363
 364 module_param(debug, bool, S_IRUGO | S_IWUSR);
 365 MODULE_PARM_DESC(debug, "Debug enabled or not");