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
   9  * 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
  15  *      problems.
  16  *
  17  * (04/08/2001) gb
  18  *      Identify version on module load.
  19  *
  20  * (11/01/2000) Adam J. Richter
  21  *      usb_device_id table support
  22  *
  23  * (10/05/2000) gkh
  24  *      Fixed bug with urb->dev not being set properly, now that the usb
  25  *      core needs it.
  26  *
  27  * (08/28/2000) gkh
  28  *      Added locks for SMP safeness.
  29  *      Fixed MOD_INC and MOD_DEC logic and the ability to open a port more
  30  *      than once.
  31  *      Fixed potential race in omninet_write_bulk_callback
  32  *
  33  * (07/19/2000) gkh
  34  *      Added module_init and module_exit functions to handle the fact that this
  35  *      driver is a loadable module now.
  36  *
  37  */
  38
  39 #include <linux/kernel.h>
  40 #include <linux/errno.h>
  41 #include <linux/init.h>
  42 #include <linux/slab.h>
  43 #include <linux/tty.h>
  44 #include <linux/tty_driver.h>
  45 #include <linux/tty_flip.h>
  46 #include <linux/module.h>
  47 #include <linux/spinlock.h>
  48 #include <linux/uaccess.h>
  49 #include <linux/usb.h>
  50 #include <linux/usb/serial.h>
  51
  52 static int debug;
  53
  54 /*
  55  * Version Information
  56  */
  57 #define DRIVER_VERSION "v1.1"
  58 #define DRIVER_AUTHOR "Alessandro Zummo"
  59 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
  60
  61 #define ZYXEL_VENDOR_ID         0x0586
  62 #define ZYXEL_OMNINET_ID        0x1000
  63 /* This one seems to be a re-branded ZyXEL device */
  64 #define BT_IGNITIONPRO_ID       0x2000
  65
  66 /* function prototypes */
  67 static int  omninet_open(struct tty_struct *tty, struct usb_serial_port *port,
  68                                                         struct file *filp);
  69 static void omninet_close(struct tty_struct *tty, struct usb_serial_port *port,
  70                                                         struct file *filp);
  71 static void omninet_read_bulk_callback(struct urb *urb);
  72 static void omninet_write_bulk_callback(struct urb *urb);
  73 static int  omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
  74                                 const unsigned char *buf, int count);
  75 static int  omninet_write_room(struct tty_struct *tty);
  76 static void omninet_shutdown(struct usb_serial *serial);
  77 static int omninet_attach(struct usb_serial *serial);
  78
  79 static struct usb_device_id id_table[] = {
  80         { USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
  81         { USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
  82         { }                                             /* Terminating entry */
  83 };
  84
  85 MODULE_DEVICE_TABLE(usb, id_table);
  86
  87 static struct usb_driver omninet_driver = {
  88         .name =         "omninet",
  89         .probe =        usb_serial_probe,
  90         .disconnect =   usb_serial_disconnect,
  91         .id_table =     id_table,
  92         .no_dynamic_id =        1,
  93 };
  94
  95
  96 static struct usb_serial_driver zyxel_omninet_device = {
  97         .driver = {
  98                 .owner =        THIS_MODULE,
  99                 .name =         "omninet",
 100         },
 101         .description =          "ZyXEL - omni.net lcd plus usb",
 102         .usb_driver =           &omninet_driver,
 103         .id_table =             id_table,
 104         .num_ports =            1,
 105         .attach =               omninet_attach,
 106         .open =                 omninet_open,
 107         .close =                omninet_close,
 108         .write =                omninet_write,
 109         .write_room =           omninet_write_room,
 110         .read_bulk_callback =   omninet_read_bulk_callback,
 111         .write_bulk_callback =  omninet_write_bulk_callback,
 112         .shutdown =             omninet_shutdown,
 113 };
 114
 115
 116 /* The protocol.
 117  *
 118  * The omni.net always exchange 64 bytes of data with the host. The first
 119  * four bytes are the control header, you can see it in the above structure.
 120  *
 121  * oh_seq is a sequence number. Don't know if/how it's used.
 122  * oh_len is the length of the data bytes in the packet.
 123  * oh_xxx Bit-mapped, related to handshaking and status info.
 124  *      I normally set it to 0x03 in trasmitted frames.
 125  *      7: Active when the TA is in a CONNECTed state.
 126  *      6: unknown
 127  *      5: handshaking, unknown
 128  *      4: handshaking, unknown
 129  *      3: unknown, usually 0
 130  *      2: unknown, usually 0
 131  *      1: handshaking, unknown, usually set to 1 in trasmitted frames
 132  *      0: handshaking, unknown, usually set to 1 in trasmitted frames
 133  * oh_pad Probably a pad byte.
 134  *
 135  * After the header you will find data bytes if oh_len was greater than zero.
 136  *
 137  */
 138
 139 struct omninet_header {
 140         __u8    oh_seq;
 141         __u8    oh_len;
 142         __u8    oh_xxx;
 143         __u8    oh_pad;
 144 };
 145
 146 struct omninet_data {
 147         __u8    od_outseq;      /* Sequence number for bulk_out URBs */
 148 };
 149
 150 static int omninet_attach(struct usb_serial *serial)
 151 {
 152         struct omninet_data *od;
 153         struct usb_serial_port *port = serial->port[0];
 154
 155         od = kmalloc(sizeof(struct omninet_data), GFP_KERNEL);
 156         if (!od) {
 157                 dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n",
 158                         __func__, sizeof(struct omninet_data));
 159                 return -ENOMEM;
 160         }
 161         usb_set_serial_port_data(port, od);
 162         return 0;
 163 }
 164
 165 static int omninet_open(struct tty_struct *tty,
 166                         struct usb_serial_port *port, struct file *filp)
 167 {
 168         struct usb_serial       *serial = port->serial;
 169         struct usb_serial_port  *wport;
 170         int                     result = 0;
 171
 172         dbg("%s - port %d", __func__, port->number);
 173
 174         wport = serial->port[1];
 175         tty_port_tty_set(&wport->port, tty);
 176
 177         /* Start reading from the device */
 178         usb_fill_bulk_urb(port->read_urb, serial->dev,
 179                         usb_rcvbulkpipe(serial->dev,
 180                                 port->bulk_in_endpointAddress),
 181                         port->read_urb->transfer_buffer,
 182                         port->read_urb->transfer_buffer_length,
 183                         omninet_read_bulk_callback, port);
 184         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 185         if (result)
 186                 dev_err(&port->dev,
 187                         "%s - failed submitting read urb, error %d\n",
 188                         __func__, result);
 189         return result;
 190 }
 191
 192 static void omninet_close(struct tty_struct *tty,
 193                         struct usb_serial_port *port, struct file *filp)
 194 {
 195         dbg("%s - port %d", __func__, port->number);
 196         usb_kill_urb(port->read_urb);
 197 }
 198
 199
 200 #define OMNINET_DATAOFFSET      0x04
 201 #define OMNINET_HEADERLEN       sizeof(struct omninet_header)
 202 #define OMNINET_BULKOUTSIZE     (64 - OMNINET_HEADERLEN)
 203
 204 static void omninet_read_bulk_callback(struct urb *urb)
 205 {
 206         struct usb_serial_port  *port   = urb->context;
 207         unsigned char           *data   = urb->transfer_buffer;
 208         struct omninet_header   *header = (struct omninet_header *) &data[0];
 209         int status = urb->status;
 210         int result;
 211         int i;
 212
 213         dbg("%s - port %d", __func__, port->number);
 214
 215         if (status) {
 216                 dbg("%s - nonzero read bulk status received: %d",
 217                     __func__, status);
 218                 return;
 219         }
 220
 221         if (debug && header->oh_xxx != 0x30) {
 222                 if (urb->actual_length) {
 223                         printk(KERN_DEBUG __FILE__
 224                                         ": omninet_read %d: ", header->oh_len);
 225                         for (i = 0; i < (header->oh_len +
 226                                                 OMNINET_HEADERLEN); i++)
 227                                 printk("%.2x ", data[i]);
 228                         printk("\n");
 229                 }
 230         }
 231
 232         if (urb->actual_length && header->oh_len) {
 233                 struct tty_struct *tty = tty_port_tty_get(&port->port);
 234                 tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
 235                                                         header->oh_len);
 236                 tty_flip_buffer_push(tty);
 237                 tty_kref_put(tty);
 238         }
 239
 240         /* Continue trying to always read  */
 241         usb_fill_bulk_urb(urb, port->serial->dev,
 242                         usb_rcvbulkpipe(port->serial->dev,
 243                                         port->bulk_in_endpointAddress),
 244                         urb->transfer_buffer, urb->transfer_buffer_length,
 245                         omninet_read_bulk_callback, port);
 246         result = usb_submit_urb(urb, GFP_ATOMIC);
 247         if (result)
 248                 dev_err(&port->dev,
 249                         "%s - failed resubmitting read urb, error %d\n",
 250                         __func__, result);
 251
 252         return;
 253 }
 254
 255 static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
 256                                         const unsigned char *buf, int count)
 257 {
 258         struct usb_serial *serial = port->serial;
 259         struct usb_serial_port *wport = serial->port[1];
 260
 261         struct omninet_data *od = usb_get_serial_port_data(port);
 262         struct omninet_header *header = (struct omninet_header *)
 263                                         wport->write_urb->transfer_buffer;
 264
 265         int                     result;
 266
 267         dbg("%s - port %d", __func__, port->number);
 268
 269         if (count == 0) {
 270                 dbg("%s - write request of 0 bytes", __func__);
 271                 return 0;
 272         }
 273
 274         spin_lock_bh(&wport->lock);
 275         if (wport->write_urb_busy) {
 276                 spin_unlock_bh(&wport->lock);
 277                 dbg("%s - already writing", __func__);
 278                 return 0;
 279         }
 280         wport->write_urb_busy = 1;
 281         spin_unlock_bh(&wport->lock);
 282
 283         count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
 284
 285         memcpy(wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET,
 286                                                                 buf, count);
 287
 288         usb_serial_debug_data(debug, &port->dev, __func__, count,
 289                                         wport->write_urb->transfer_buffer);
 290
 291         header->oh_seq  = od->od_outseq++;
 292         header->oh_len  = count;
 293         header->oh_xxx  = 0x03;
 294         header->oh_pad  = 0x00;
 295
 296         /* send the data out the bulk port, always 64 bytes */
 297         wport->write_urb->transfer_buffer_length = 64;
 298
 299         wport->write_urb->dev = serial->dev;
 300         result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
 301         if (result) {
 302                 wport->write_urb_busy = 0;
 303                 dev_err(&port->dev,
 304                         "%s - failed submitting write urb, error %d\n",
 305                         __func__, result);
 306         } else
 307                 result = count;
 308
 309         return result;
 310 }
 311
 312
 313 static int omninet_write_room(struct tty_struct *tty)
 314 {
 315         struct usb_serial_port *port = tty->driver_data;
 316         struct usb_serial       *serial = port->serial;
 317         struct usb_serial_port  *wport  = serial->port[1];
 318
 319         int room = 0; /* Default: no room */
 320
 321         /* FIXME: no consistent locking for write_urb_busy */
 322         if (wport->write_urb_busy)
 323                 room = wport->bulk_out_size - OMNINET_HEADERLEN;
 324
 325         dbg("%s - returns %d", __func__, room);
 326
 327         return room;
 328 }
 329
 330 static void omninet_write_bulk_callback(struct urb *urb)
 331 {
 332 /*      struct omninet_header   *header = (struct omninet_header  *)
 333                                                 urb->transfer_buffer; */
 334         struct usb_serial_port  *port   =  urb->context;
 335         int status = urb->status;
 336
 337         dbg("%s - port %0x\n", __func__, port->number);
 338
 339         port->write_urb_busy = 0;
 340         if (status) {
 341                 dbg("%s - nonzero write bulk status received: %d",
 342                     __func__, status);
 343                 return;
 344         }
 345
 346         usb_serial_port_softint(port);
 347 }
 348
 349
 350 static void omninet_shutdown(struct usb_serial *serial)
 351 {
 352         struct usb_serial_port *wport = serial->port[1];
 353         struct usb_serial_port *port = serial->port[0];
 354         dbg("%s", __func__);
 355
 356         usb_kill_urb(wport->write_urb);
 357         kfree(usb_get_serial_port_data(port));
 358 }
 359
 360
 361 static int __init omninet_init(void)
 362 {
 363         int retval;
 364         retval = usb_serial_register(&zyxel_omninet_device);
 365         if (retval)
 366                 goto failed_usb_serial_register;
 367         retval = usb_register(&omninet_driver);
 368         if (retval)
 369                 goto failed_usb_register;
 370         printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
 371                DRIVER_DESC "\n");
 372         return 0;
 373 failed_usb_register:
 374         usb_serial_deregister(&zyxel_omninet_device);
 375 failed_usb_serial_register:
 376         return retval;
 377 }
 378
 379
 380 static void __exit omninet_exit(void)
 381 {
 382         usb_deregister(&omninet_driver);
 383         usb_serial_deregister(&zyxel_omninet_device);
 384 }
 385
 386
 387 module_init(omninet_init);
 388 module_exit(omninet_exit);
 389
 390 MODULE_AUTHOR(DRIVER_AUTHOR);
 391 MODULE_DESCRIPTION(DRIVER_DESC);
 392 MODULE_LICENSE("GPL");
 393
 394 module_param(debug, bool, S_IRUGO | S_IWUSR);
 395 MODULE_PARM_DESC(debug, "Debug enabled or not");