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