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 usb_serial_port *port, struct file *filp);
  65 static void omninet_close               (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 usb_serial_port *port, const unsigned char *buf, int count);
  69 static int  omninet_write_room          (struct usb_serial_port *port);
  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 usb_serial_port *port, struct file *filp)
 161 {
 162         struct usb_serial       *serial = port->serial;
 163         struct usb_serial_port  *wport;
 164         int                     result = 0;
 165
 166         dbg("%s - port %d", __func__, port->number);
 167
 168         wport = serial->port[1];
 169         wport->tty = port->tty;
 170
 171         /* Start reading from the device */
 172         usb_fill_bulk_urb(port->read_urb, serial->dev,
 173                       usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
 174                       port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
 175                       omninet_read_bulk_callback, port);
 176         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 177         if (result) {
 178                 err("%s - failed submitting read urb, error %d", __func__, result);
 179         }
 180
 181         return result;
 182 }
 183
 184 static void omninet_close (struct usb_serial_port *port, struct file * filp)
 185 {
 186         dbg("%s - port %d", __func__, port->number);
 187         usb_kill_urb(port->read_urb);
 188 }
 189
 190
 191 #define OMNINET_DATAOFFSET      0x04
 192 #define OMNINET_HEADERLEN       sizeof(struct omninet_header)
 193 #define OMNINET_BULKOUTSIZE     (64 - OMNINET_HEADERLEN)
 194
 195 static void omninet_read_bulk_callback (struct urb *urb)
 196 {
 197         struct usb_serial_port  *port   = urb->context;
 198         unsigned char           *data   = urb->transfer_buffer;
 199         struct omninet_header   *header = (struct omninet_header *) &data[0];
 200         int status = urb->status;
 201         int i;
 202         int result;
 203
 204         dbg("%s - port %d", __func__, port->number);
 205
 206         if (status) {
 207                 dbg("%s - nonzero read bulk status received: %d",
 208                     __func__, status);
 209                 return;
 210         }
 211
 212         if ((debug) && (header->oh_xxx != 0x30)) {
 213                 if (urb->actual_length) {
 214                         printk (KERN_DEBUG __FILE__ ": omninet_read %d: ", header->oh_len);
 215                         for (i = 0; i < (header->oh_len + OMNINET_HEADERLEN); i++) {
 216                                 printk ("%.2x ", data[i]);
 217                         }
 218                         printk ("\n");
 219                 }
 220         }
 221
 222         if (urb->actual_length && header->oh_len) {
 223                 for (i = 0; i < header->oh_len; i++) {
 224                          tty_insert_flip_char(port->tty, data[OMNINET_DATAOFFSET + i], 0);
 225                 }
 226                 tty_flip_buffer_push(port->tty);
 227         }
 228
 229         /* Continue trying to always read  */
 230         usb_fill_bulk_urb(urb, port->serial->dev,
 231                       usb_rcvbulkpipe(port->serial->dev, port->bulk_in_endpointAddress),
 232                       urb->transfer_buffer, urb->transfer_buffer_length,
 233                       omninet_read_bulk_callback, port);
 234         result = usb_submit_urb(urb, GFP_ATOMIC);
 235         if (result)
 236                 err("%s - failed resubmitting read urb, error %d", __func__, result);
 237
 238         return;
 239 }
 240
 241 static int omninet_write (struct usb_serial_port *port, const unsigned char *buf, int count)
 242 {
 243         struct usb_serial       *serial = port->serial;
 244         struct usb_serial_port  *wport  = serial->port[1];
 245
 246         struct omninet_data     *od     = usb_get_serial_port_data(port);
 247         struct omninet_header   *header = (struct omninet_header *) wport->write_urb->transfer_buffer;
 248
 249         int                     result;
 250
 251         dbg("%s - port %d", __func__, port->number);
 252
 253         if (count == 0) {
 254                 dbg("%s - write request of 0 bytes", __func__);
 255                 return (0);
 256         }
 257
 258         spin_lock_bh(&wport->lock);
 259         if (wport->write_urb_busy) {
 260                 spin_unlock_bh(&wport->lock);
 261                 dbg("%s - already writing", __func__);
 262                 return 0;
 263         }
 264         wport->write_urb_busy = 1;
 265         spin_unlock_bh(&wport->lock);
 266
 267         count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
 268
 269         memcpy (wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET, buf, count);
 270
 271         usb_serial_debug_data(debug, &port->dev, __func__, count, wport->write_urb->transfer_buffer);
 272
 273         header->oh_seq  = od->od_outseq++;
 274         header->oh_len  = count;
 275         header->oh_xxx  = 0x03;
 276         header->oh_pad  = 0x00;
 277
 278         /* send the data out the bulk port, always 64 bytes */
 279         wport->write_urb->transfer_buffer_length = 64;
 280
 281         wport->write_urb->dev = serial->dev;
 282         result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
 283         if (result) {
 284                 wport->write_urb_busy = 0;
 285                 err("%s - failed submitting write urb, error %d", __func__, result);
 286         } else
 287                 result = count;
 288
 289         return result;
 290 }
 291
 292
 293 static int omninet_write_room (struct usb_serial_port *port)
 294 {
 295         struct usb_serial       *serial = port->serial;
 296         struct usb_serial_port  *wport  = serial->port[1];
 297
 298         int room = 0; /* Default: no room */
 299
 300         /* FIXME: no consistent locking for write_urb_busy */
 301         if (wport->write_urb_busy)
 302                 room = wport->bulk_out_size - OMNINET_HEADERLEN;
 303
 304         dbg("%s - returns %d", __func__, room);
 305
 306         return (room);
 307 }
 308
 309 static void omninet_write_bulk_callback (struct urb *urb)
 310 {
 311 /*      struct omninet_header   *header = (struct omninet_header  *) urb->transfer_buffer; */
 312         struct usb_serial_port  *port   =  urb->context;
 313         int status = urb->status;
 314
 315         dbg("%s - port %0x\n", __func__, port->number);
 316
 317         port->write_urb_busy = 0;
 318         if (status) {
 319                 dbg("%s - nonzero write bulk status received: %d",
 320                     __func__, status);
 321                 return;
 322         }
 323
 324         usb_serial_port_softint(port);
 325 }
 326
 327
 328 static void omninet_shutdown (struct usb_serial *serial)
 329 {
 330         struct usb_serial_port *wport = serial->port[1];
 331         struct usb_serial_port *port = serial->port[0];
 332         dbg ("%s", __func__);
 333
 334         usb_kill_urb(wport->write_urb);
 335         kfree(usb_get_serial_port_data(port));
 336 }
 337
 338
 339 static int __init omninet_init (void)
 340 {
 341         int retval;
 342         retval = usb_serial_register(&zyxel_omninet_device);
 343         if (retval)
 344                 goto failed_usb_serial_register;
 345         retval = usb_register(&omninet_driver);
 346         if (retval)
 347                 goto failed_usb_register;
 348         info(DRIVER_VERSION ":" DRIVER_DESC);
 349         return 0;
 350 failed_usb_register:
 351         usb_serial_deregister(&zyxel_omninet_device);
 352 failed_usb_serial_register:
 353         return retval;
 354 }
 355
 356
 357 static void __exit omninet_exit (void)
 358 {
 359         usb_deregister (&omninet_driver);
 360         usb_serial_deregister (&zyxel_omninet_device);
 361 }
 362
 363
 364 module_init(omninet_init);
 365 module_exit(omninet_exit);
 366
 367 MODULE_AUTHOR( DRIVER_AUTHOR );
 368 MODULE_DESCRIPTION( DRIVER_DESC );
 369 MODULE_LICENSE("GPL");
 370
 371 module_param(debug, bool, S_IRUGO | S_IWUSR);
 372 MODULE_PARM_DESC(debug, "Debug enabled or not");