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
  14 #include <linux/kernel.h>
  15 #include <linux/errno.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <linux/tty.h>
  19 #include <linux/tty_driver.h>
  20 #include <linux/tty_flip.h>
  21 #include <linux/module.h>
  22 #include <linux/uaccess.h>
  23 #include <linux/usb.h>
  24 #include <linux/usb/serial.h>
  25
  26 static bool debug;
  27
  28 /*
  29  * Version Information
  30  */
  31 #define DRIVER_VERSION "v1.1"
  32 #define DRIVER_AUTHOR "Alessandro Zummo"
  33 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
  34
  35 #define ZYXEL_VENDOR_ID         0x0586
  36 #define ZYXEL_OMNINET_ID        0x1000
  37 /* This one seems to be a re-branded ZyXEL device */
  38 #define BT_IGNITIONPRO_ID       0x2000
  39
  40 /* function prototypes */
  41 static int  omninet_open(struct tty_struct *tty, struct usb_serial_port *port);
  42 static void omninet_close(struct usb_serial_port *port);
  43 static void omninet_read_bulk_callback(struct urb *urb);
  44 static void omninet_write_bulk_callback(struct urb *urb);
  45 static int  omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
  46                                 const unsigned char *buf, int count);
  47 static int  omninet_write_room(struct tty_struct *tty);
  48 static void omninet_disconnect(struct usb_serial *serial);
  49 static void omninet_release(struct usb_serial *serial);
  50 static int omninet_attach(struct usb_serial *serial);
  51
  52 static const struct usb_device_id id_table[] = {
  53         { USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
  54         { USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
  55         { }                                             /* Terminating entry */
  56 };
  57
  58 MODULE_DEVICE_TABLE(usb, id_table);
  59
  60 static struct usb_driver omninet_driver = {
  61         .name =         "omninet",
  62         .id_table =     id_table,
  63 };
  64
  65
  66 static struct usb_serial_driver zyxel_omninet_device = {
  67         .driver = {
  68                 .owner =        THIS_MODULE,
  69                 .name =         "omninet",
  70         },
  71         .description =          "ZyXEL - omni.net lcd plus usb",
  72         .id_table =             id_table,
  73         .num_ports =            1,
  74         .attach =               omninet_attach,
  75         .open =                 omninet_open,
  76         .close =                omninet_close,
  77         .write =                omninet_write,
  78         .write_room =           omninet_write_room,
  79         .read_bulk_callback =   omninet_read_bulk_callback,
  80         .write_bulk_callback =  omninet_write_bulk_callback,
  81         .disconnect =           omninet_disconnect,
  82         .release =              omninet_release,
  83 };
  84
  85 static struct usb_serial_driver * const serial_drivers[] = {
  86         &zyxel_omninet_device, NULL
  87 };
  88
  89
  90 /* The protocol.
  91  *
  92  * The omni.net always exchange 64 bytes of data with the host. The first
  93  * four bytes are the control header, you can see it in the above structure.
  94  *
  95  * oh_seq is a sequence number. Don't know if/how it's used.
  96  * oh_len is the length of the data bytes in the packet.
  97  * oh_xxx Bit-mapped, related to handshaking and status info.
  98  *      I normally set it to 0x03 in trasmitted frames.
  99  *      7: Active when the TA is in a CONNECTed state.
 100  *      6: unknown
 101  *      5: handshaking, unknown
 102  *      4: handshaking, unknown
 103  *      3: unknown, usually 0
 104  *      2: unknown, usually 0
 105  *      1: handshaking, unknown, usually set to 1 in trasmitted frames
 106  *      0: handshaking, unknown, usually set to 1 in trasmitted frames
 107  * oh_pad Probably a pad byte.
 108  *
 109  * After the header you will find data bytes if oh_len was greater than zero.
 110  *
 111  */
 112
 113 struct omninet_header {
 114         __u8    oh_seq;
 115         __u8    oh_len;
 116         __u8    oh_xxx;
 117         __u8    oh_pad;
 118 };
 119
 120 struct omninet_data {
 121         __u8    od_outseq;      /* Sequence number for bulk_out URBs */
 122 };
 123
 124 static int omninet_attach(struct usb_serial *serial)
 125 {
 126         struct omninet_data *od;
 127         struct usb_serial_port *port = serial->port[0];
 128
 129         od = kmalloc(sizeof(struct omninet_data), GFP_KERNEL);
 130         if (!od) {
 131                 dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n",
 132                         __func__, sizeof(struct omninet_data));
 133                 return -ENOMEM;
 134         }
 135         usb_set_serial_port_data(port, od);
 136         return 0;
 137 }
 138
 139 static int omninet_open(struct tty_struct *tty, struct usb_serial_port *port)
 140 {
 141         struct usb_serial       *serial = port->serial;
 142         struct usb_serial_port  *wport;
 143         int                     result = 0;
 144
 145         wport = serial->port[1];
 146         tty_port_tty_set(&wport->port, tty);
 147
 148         /* Start reading from the device */
 149         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 150         if (result)
 151                 dev_err(&port->dev,
 152                         "%s - failed submitting read urb, error %d\n",
 153                         __func__, result);
 154         return result;
 155 }
 156
 157 static void omninet_close(struct usb_serial_port *port)
 158 {
 159         usb_kill_urb(port->read_urb);
 160 }
 161
 162
 163 #define OMNINET_DATAOFFSET      0x04
 164 #define OMNINET_HEADERLEN       sizeof(struct omninet_header)
 165 #define OMNINET_BULKOUTSIZE     (64 - OMNINET_HEADERLEN)
 166
 167 static void omninet_read_bulk_callback(struct urb *urb)
 168 {
 169         struct usb_serial_port  *port   = urb->context;
 170         unsigned char           *data   = urb->transfer_buffer;
 171         struct omninet_header   *header = (struct omninet_header *) &data[0];
 172         int status = urb->status;
 173         int result;
 174         int i;
 175
 176         if (status) {
 177                 dbg("%s - nonzero read bulk status received: %d",
 178                     __func__, status);
 179                 return;
 180         }
 181
 182         if (debug && header->oh_xxx != 0x30) {
 183                 if (urb->actual_length) {
 184                         printk(KERN_DEBUG "%s: omninet_read %d: ",
 185                                __FILE__, header->oh_len);
 186                         for (i = 0; i < (header->oh_len +
 187                                                 OMNINET_HEADERLEN); i++)
 188                                 printk("%.2x ", data[i]);
 189                         printk("\n");
 190                 }
 191         }
 192
 193         if (urb->actual_length && header->oh_len) {
 194                 struct tty_struct *tty = tty_port_tty_get(&port->port);
 195                 tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
 196                                                         header->oh_len);
 197                 tty_flip_buffer_push(tty);
 198                 tty_kref_put(tty);
 199         }
 200
 201         /* Continue trying to always read  */
 202         result = usb_submit_urb(urb, GFP_ATOMIC);
 203         if (result)
 204                 dev_err(&port->dev,
 205                         "%s - failed resubmitting read urb, error %d\n",
 206                         __func__, result);
 207 }
 208
 209 static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
 210                                         const unsigned char *buf, int count)
 211 {
 212         struct usb_serial *serial = port->serial;
 213         struct usb_serial_port *wport = serial->port[1];
 214
 215         struct omninet_data *od = usb_get_serial_port_data(port);
 216         struct omninet_header *header = (struct omninet_header *)
 217                                         wport->write_urb->transfer_buffer;
 218
 219         int                     result;
 220
 221         if (count == 0) {
 222                 dbg("%s - write request of 0 bytes", __func__);
 223                 return 0;
 224         }
 225
 226         if (!test_and_clear_bit(0, &port->write_urbs_free)) {
 227                 dbg("%s - already writing", __func__);
 228                 return 0;
 229         }
 230
 231         count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
 232
 233         memcpy(wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET,
 234                                                                 buf, count);
 235
 236         usb_serial_debug_data(debug, &port->dev, __func__, count,
 237                                         wport->write_urb->transfer_buffer);
 238
 239         header->oh_seq  = od->od_outseq++;
 240         header->oh_len  = count;
 241         header->oh_xxx  = 0x03;
 242         header->oh_pad  = 0x00;
 243
 244         /* send the data out the bulk port, always 64 bytes */
 245         wport->write_urb->transfer_buffer_length = 64;
 246
 247         result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
 248         if (result) {
 249                 set_bit(0, &wport->write_urbs_free);
 250                 dev_err_console(port,
 251                         "%s - failed submitting write urb, error %d\n",
 252                         __func__, result);
 253         } else
 254                 result = count;
 255
 256         return result;
 257 }
 258
 259
 260 static int omninet_write_room(struct tty_struct *tty)
 261 {
 262         struct usb_serial_port *port = tty->driver_data;
 263         struct usb_serial       *serial = port->serial;
 264         struct usb_serial_port  *wport  = serial->port[1];
 265
 266         int room = 0; /* Default: no room */
 267
 268         if (test_bit(0, &wport->write_urbs_free))
 269                 room = wport->bulk_out_size - OMNINET_HEADERLEN;
 270
 271         dbg("%s - returns %d", __func__, room);
 272
 273         return room;
 274 }
 275
 276 static void omninet_write_bulk_callback(struct urb *urb)
 277 {
 278 /*      struct omninet_header   *header = (struct omninet_header  *)
 279                                                 urb->transfer_buffer; */
 280         struct usb_serial_port  *port   =  urb->context;
 281         int status = urb->status;
 282
 283         set_bit(0, &port->write_urbs_free);
 284         if (status) {
 285                 dbg("%s - nonzero write bulk status received: %d",
 286                     __func__, status);
 287                 return;
 288         }
 289
 290         usb_serial_port_softint(port);
 291 }
 292
 293
 294 static void omninet_disconnect(struct usb_serial *serial)
 295 {
 296         struct usb_serial_port *wport = serial->port[1];
 297
 298         usb_kill_urb(wport->write_urb);
 299 }
 300
 301
 302 static void omninet_release(struct usb_serial *serial)
 303 {
 304         struct usb_serial_port *port = serial->port[0];
 305
 306         kfree(usb_get_serial_port_data(port));
 307 }
 308
 309 module_usb_serial_driver(omninet_driver, serial_drivers);
 310
 311 MODULE_AUTHOR(DRIVER_AUTHOR);
 312 MODULE_DESCRIPTION(DRIVER_DESC);
 313 MODULE_LICENSE("GPL");
 314
 315 module_param(debug, bool, S_IRUGO | S_IWUSR);
 316 MODULE_PARM_DESC(debug, "Debug enabled or not");