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
   5  *      modify it under the terms of the GNU General Public License version
   6  *      2 as published by the Free Software Foundation.
   7  *
   8  * See Documentation/usb/usb-serial.txt for more information on using this driver
   9  *
  10  * Please report both successes and troubles to the author at omninet@kroah.com
  11  *
  12  * (05/30/2001) gkh
  13  *      switched from using spinlock to a semaphore, which fixes lots of problems.
  14  *
  15  * (04/08/2001) gb
  16  *      Identify version on module load.
  17  *
  18  * (11/01/2000) Adam J. Richter
  19  *      usb_device_id table support
  20  *
  21  * (10/05/2000) gkh
  22  *      Fixed bug with urb->dev not being set properly, now that the usb
  23  *      core needs it.
  24  *
  25  * (08/28/2000) gkh
  26  *      Added locks for SMP safeness.
  27  *      Fixed MOD_INC and MOD_DEC logic and the ability to open a port more
  28  *      than once.
  29  *      Fixed potential race in omninet_write_bulk_callback
  30  *
  31  * (07/19/2000) gkh
  32  *      Added module_init and module_exit functions to handle the fact that this
  33  *      driver is a loadable module now.
  34  *
  35  */
  36
  37 #include <linux/kernel.h>
  38 #include <linux/errno.h>
  39 #include <linux/init.h>
  40 #include <linux/slab.h>
  41 #include <linux/tty.h>
  42 #include <linux/tty_driver.h>
  43 #include <linux/tty_flip.h>
  44 #include <linux/module.h>
  45 #include <linux/spinlock.h>
  46 #include <asm/uaccess.h>
  47 #include <linux/usb.h>
  48 #include <linux/usb/serial.h>
  49
  50 static int debug;
  51
  52 /*
  53  * Version Information
  54  */
  55 #define DRIVER_VERSION "v1.1"
  56 #define DRIVER_AUTHOR "Alessandro Zummo"
  57 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
  58
  59 #define ZYXEL_VENDOR_ID         0x0586
  60 #define ZYXEL_OMNINET_ID        0x1000
  61 #define BT_IGNITIONPRO_ID       0x2000  /* This one seems to be a re-branded ZyXEL device */
  62
  63 /* function prototypes */
  64 static int  omninet_open                (struct tty_struct *tty, struct usb_serial_port *port, struct file *filp);
  65 static void omninet_close               (struct tty_struct *tty, struct usb_serial_port *port, struct file *filp);
  66 static void omninet_read_bulk_callback  (struct urb *urb);
  67 static void omninet_write_bulk_callback (struct urb *urb);
  68 static int  omninet_write               (struct tty_struct *tty, struct usb_serial_port *port, const unsigned char *buf, int count);
  69 static int  omninet_write_room          (struct tty_struct *tty);
  70 static void omninet_shutdown            (struct usb_serial *serial);
  71 static int omninet_attach               (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         .usb_driver =           &omninet_driver,
  97         .id_table =             id_table,
  98         .num_ports =            1,
  99         .attach =               omninet_attach,
 100         .open =                 omninet_open,
 101         .close =                omninet_close,
 102         .write =                omninet_write,
 103         .write_room =           omninet_write_room,
 104         .read_bulk_callback =   omninet_read_bulk_callback,
 105         .write_bulk_callback =  omninet_write_bulk_callback,
 106         .shutdown =             omninet_shutdown,
 107 };
 108
 109
 110 /* The protocol.
 111  *
 112  * The omni.net always exchange 64 bytes of data with the host. The first
 113  * four bytes are the control header, you can see it in the above structure.
 114  *
 115  * oh_seq is a sequence number. Don't know if/how it's used.
 116  * oh_len is the length of the data bytes in the packet.
 117  * oh_xxx Bit-mapped, related to handshaking and status info.
 118  *      I normally set it to 0x03 in trasmitted frames.
 119  *      7: Active when the TA is in a CONNECTed state.
 120  *      6: unknown
 121  *      5: handshaking, unknown
 122  *      4: handshaking, unknown
 123  *      3: unknown, usually 0
 124  *      2: unknown, usually 0
 125  *      1: handshaking, unknown, usually set to 1 in trasmitted frames
 126  *      0: handshaking, unknown, usually set to 1 in trasmitted frames
 127  * oh_pad Probably a pad byte.
 128  *
 129  * After the header you will find data bytes if oh_len was greater than zero.
 130  *
 131  */
 132
 133 struct omninet_header
 134 {
 135         __u8    oh_seq;
 136         __u8    oh_len;
 137         __u8    oh_xxx;
 138         __u8    oh_pad;
 139 };
 140
 141 struct omninet_data
 142 {
 143         __u8    od_outseq;      // Sequence number for bulk_out URBs
 144 };
 145
 146 static int omninet_attach (struct usb_serial *serial)
 147 {
 148         struct omninet_data *od;
 149         struct usb_serial_port *port = serial->port[0];
 150
 151         od = kmalloc( sizeof(struct omninet_data), GFP_KERNEL );
 152         if( !od ) {
 153                 err("%s- kmalloc(%Zd) failed.", __func__, sizeof(struct omninet_data));
 154                 return -ENOMEM;
 155         }
 156         usb_set_serial_port_data(port, od);
 157         return 0;
 158 }
 159
 160 static int omninet_open(struct tty_struct *tty,
 161                         struct usb_serial_port *port, struct file *filp)
 162 {
 163         struct usb_serial       *serial = port->serial;
 164         struct usb_serial_port  *wport;
 165         int                     result = 0;
 166
 167         dbg("%s - port %d", __func__, port->number);
 168
 169         wport = serial->port[1];
 170         wport->port.tty = tty;          /* FIXME */
 171
 172         /* Start reading from the device */
 173         usb_fill_bulk_urb(port->read_urb, serial->dev,
 174                       usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
 175                       port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
 176                       omninet_read_bulk_callback, port);
 177         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 178         if (result) {
 179                 err("%s - failed submitting read urb, error %d", __func__, result);
 180         }
 181
 182         return result;
 183 }
 184
 185 static void omninet_close(struct tty_struct *tty,
 186                         struct usb_serial_port *port, struct file * filp)
 187 {
 188         dbg("%s - port %d", __func__, port->number);
 189         usb_kill_urb(port->read_urb);
 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)
 198 {
 199         struct usb_serial_port  *port   = urb->context;
 200         unsigned char           *data   = urb->transfer_buffer;
 201         struct omninet_header   *header = (struct omninet_header *) &data[0];
 202         int status = urb->status;
 203         int i;
 204         int result;
 205
 206         dbg("%s - port %d", __func__, port->number);
 207
 208         if (status) {
 209                 dbg("%s - nonzero read bulk status received: %d",
 210                     __func__, status);
 211                 return;
 212         }
 213
 214         if ((debug) && (header->oh_xxx != 0x30)) {
 215                 if (urb->actual_length) {
 216                         printk (KERN_DEBUG __FILE__ ": omninet_read %d: ", header->oh_len);
 217                         for (i = 0; i < (header->oh_len + OMNINET_HEADERLEN); i++) {
 218                                 printk ("%.2x ", data[i]);
 219                         }
 220                         printk ("\n");
 221                 }
 222         }
 223
 224         if (urb->actual_length && header->oh_len) {
 225                 for (i = 0; i < header->oh_len; i++) {
 226                          tty_insert_flip_char(port->port.tty, data[OMNINET_DATAOFFSET + i], 0);
 227                 }
 228                 tty_flip_buffer_push(port->port.tty);
 229         }
 230
 231         /* Continue trying to always read  */
 232         usb_fill_bulk_urb(urb, port->serial->dev,
 233                       usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
 234                       urb->transfer_buffer, urb->transfer_buffer_length,
 235                       omninet_read_bulk_callback, port);
 236         result = usb_submit_urb(urb, GFP_ATOMIC);
 237         if (result)
 238                 err("%s - failed resubmitting read urb, error %d", __func__, result);
 239
 240         return;
 241 }
 242
 243 static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
 244                                         const unsigned char *buf, int count)
 245 {
 246         struct usb_serial       *serial = port->serial;
 247         struct usb_serial_port  *wport  = serial->port[1];
 248
 249         struct omninet_data     *od     = usb_get_serial_port_data(port);
 250         struct omninet_header   *header = (struct omninet_header *) wport->write_urb->transfer_buffer;
 251
 252         int                     result;
 253
 254         dbg("%s - port %d", __func__, port->number);
 255
 256         if (count == 0) {
 257                 dbg("%s - write request of 0 bytes", __func__);
 258                 return (0);
 259         }
 260
 261         spin_lock_bh(&wport->lock);
 262         if (wport->write_urb_busy) {
 263                 spin_unlock_bh(&wport->lock);
 264                 dbg("%s - already writing", __func__);
 265                 return 0;
 266         }
 267         wport->write_urb_busy = 1;
 268         spin_unlock_bh(&wport->lock);
 269
 270         count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
 271
 272         memcpy (wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET, buf, count);
 273
 274         usb_serial_debug_data(debug, &port->dev, __func__, count, wport->write_urb->transfer_buffer);
 275
 276         header->oh_seq  = od->od_outseq++;
 277         header->oh_len  = count;
 278         header->oh_xxx  = 0x03;
 279         header->oh_pad  = 0x00;
 280
 281         /* send the data out the bulk port, always 64 bytes */
 282         wport->write_urb->transfer_buffer_length = 64;
 283
 284         wport->write_urb->dev = serial->dev;
 285         result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
 286         if (result) {
 287                 wport->write_urb_busy = 0;
 288                 err("%s - failed submitting write urb, error %d", __func__, result);
 289         } else
 290                 result = count;
 291
 292         return result;
 293 }
 294
 295
 296 static int omninet_write_room (struct tty_struct *tty)
 297 {
 298         struct usb_serial_port *port = tty->driver_data;
 299         struct usb_serial       *serial = port->serial;
 300         struct usb_serial_port  *wport  = serial->port[1];
 301
 302         int room = 0; /* Default: no room */
 303
 304         /* FIXME: no consistent locking for write_urb_busy */
 305         if (wport->write_urb_busy)
 306                 room = wport->bulk_out_size - OMNINET_HEADERLEN;
 307
 308         dbg("%s - returns %d", __func__, room);
 309
 310         return (room);
 311 }
 312
 313 static void omninet_write_bulk_callback (struct urb *urb)
 314 {
 315 /*      struct omninet_header   *header = (struct omninet_header  *) urb->transfer_buffer; */
 316         struct usb_serial_port  *port   =  urb->context;
 317         int status = urb->status;
 318
 319         dbg("%s - port %0x\n", __func__, port->number);
 320
 321         port->write_urb_busy = 0;
 322         if (status) {
 323                 dbg("%s - nonzero write bulk status received: %d",
 324                     __func__, status);
 325                 return;
 326         }
 327
 328         usb_serial_port_softint(port);
 329 }
 330
 331
 332 static void omninet_shutdown (struct usb_serial *serial)
 333 {
 334         struct usb_serial_port *wport = serial->port[1];
 335         struct usb_serial_port *port = serial->port[0];
 336         dbg ("%s", __func__);
 337
 338         usb_kill_urb(wport->write_urb);
 339         kfree(usb_get_serial_port_data(port));
 340 }
 341
 342
 343 static int __init omninet_init (void)
 344 {
 345         int retval;
 346         retval = usb_serial_register(&zyxel_omninet_device);
 347         if (retval)
 348                 goto failed_usb_serial_register;
 349         retval = usb_register(&omninet_driver);
 350         if (retval)
 351                 goto failed_usb_register;
 352         info(DRIVER_VERSION ":" DRIVER_DESC);
 353         return 0;
 354 failed_usb_register:
 355         usb_serial_deregister(&zyxel_omninet_device);
 356 failed_usb_serial_register:
 357         return retval;
 358 }
 359
 360
 361 static void __exit omninet_exit (void)
 362 {
 363         usb_deregister (&omninet_driver);
 364         usb_serial_deregister (&zyxel_omninet_device);
 365 }
 366
 367
 368 module_init(omninet_init);
 369 module_exit(omninet_exit);
 370
 371 MODULE_AUTHOR( DRIVER_AUTHOR );
 372 MODULE_DESCRIPTION( DRIVER_DESC );
 373 MODULE_LICENSE("GPL");
 374
 375 module_param(debug, bool, S_IRUGO | S_IWUSR);
 376 MODULE_PARM_DESC(debug, "Debug enabled or not");