drivers/usb/serial/metro-usb.c

   1 /*
   2   Some of this code is credited to Linux USB open source files that are
   3   distributed with Linux.
   4
   5   Copyright:    2007 Metrologic Instruments. All rights reserved.
   6   Copyright:    2011 Azimut Ltd. <http://azimutrzn.ru/>
   7 */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/init.h>
  11 #include <linux/tty.h>
  12 #include <linux/module.h>
  13 #include <linux/usb.h>
  14 #include <linux/errno.h>
  15 #include <linux/slab.h>
  16 #include <linux/tty_driver.h>
  17 #include <linux/tty_flip.h>
  18 #include <linux/moduleparam.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/uaccess.h>
  21 #include <linux/usb/serial.h>
  22
  23 /* Version Information */
  24 #define DRIVER_VERSION "v1.2.0.0"
  25 #define DRIVER_DESC "Metrologic Instruments Inc. - USB-POS driver"
  26
  27 /* Product information. */
  28 #define FOCUS_VENDOR_ID                 0x0C2E
  29 #define FOCUS_PRODUCT_ID_BI             0x0720
  30 #define FOCUS_PRODUCT_ID_UNI            0x0700
  31
  32 #define METROUSB_SET_REQUEST_TYPE       0x40
  33 #define METROUSB_SET_MODEM_CTRL_REQUEST 10
  34 #define METROUSB_SET_BREAK_REQUEST      0x40
  35 #define METROUSB_MCR_NONE               0x08    /* Deactivate DTR and RTS. */
  36 #define METROUSB_MCR_RTS                0x0a    /* Activate RTS. */
  37 #define METROUSB_MCR_DTR                0x09    /* Activate DTR. */
  38 #define WDR_TIMEOUT                     5000    /* default urb timeout. */
  39
  40 /* Private data structure. */
  41 struct metrousb_private {
  42         spinlock_t lock;
  43         int throttled;
  44         unsigned long control_state;
  45 };
  46
  47 /* Device table list. */
  48 static struct usb_device_id id_table[] = {
  49         { USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_BI) },
  50         { USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_UNI) },
  51         { }, /* Terminating entry. */
  52 };
  53 MODULE_DEVICE_TABLE(usb, id_table);
  54
  55 /* Input parameter constants. */
  56 static bool debug;
  57
  58 /* UNI-Directional mode commands for device configure */
  59 #define UNI_CMD_OPEN    0x80
  60 #define UNI_CMD_CLOSE   0xFF
  61
  62 inline int metrousb_is_unidirectional_mode(struct usb_serial_port *port)
  63 {
  64         __u16 product_id = le16_to_cpu(
  65                 port->serial->dev->descriptor.idProduct);
  66
  67         return product_id == FOCUS_PRODUCT_ID_UNI;
  68 }
  69
  70 static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
  71 {
  72         int ret;
  73         int actual_len;
  74         u8 *buffer_cmd = NULL;
  75
  76         if (!metrousb_is_unidirectional_mode(port))
  77                 return 0;
  78
  79         buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
  80         if (!buffer_cmd)
  81                 return -ENOMEM;
  82
  83         *buffer_cmd = cmd;
  84
  85         ret = usb_interrupt_msg(port->serial->dev,
  86                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
  87                 buffer_cmd, sizeof(cmd),
  88                 &actual_len, USB_CTRL_SET_TIMEOUT);
  89
  90         kfree(buffer_cmd);
  91
  92         if (ret < 0)
  93                 return ret;
  94         else if (actual_len != sizeof(cmd))
  95                 return -EIO;
  96         return 0;
  97 }
  98
  99 static void metrousb_read_int_callback(struct urb *urb)
 100 {
 101         struct usb_serial_port *port = urb->context;
 102         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 103         struct tty_struct *tty;
 104         unsigned char *data = urb->transfer_buffer;
 105         int throttled = 0;
 106         int result = 0;
 107         unsigned long flags = 0;
 108
 109         dev_dbg(&port->dev, "%s\n", __func__);
 110
 111         switch (urb->status) {
 112         case 0:
 113                 /* Success status, read from the port. */
 114                 break;
 115         case -ECONNRESET:
 116         case -ENOENT:
 117         case -ESHUTDOWN:
 118                 /* urb has been terminated. */
 119                 dev_dbg(&port->dev,
 120                         "%s - urb shutting down, error code=%d\n",
 121                         __func__, urb->status);
 122                 return;
 123         default:
 124                 dev_dbg(&port->dev,
 125                         "%s - non-zero urb received, error code=%d\n",
 126                         __func__, urb->status);
 127                 goto exit;
 128         }
 129
 130
 131         /* Set the data read from the usb port into the serial port buffer. */
 132         tty = tty_port_tty_get(&port->port);
 133         if (!tty) {
 134                 dev_err(&port->dev, "%s - bad tty pointer - exiting\n",
 135                         __func__);
 136                 return;
 137         }
 138
 139         if (tty && urb->actual_length) {
 140                 /* Loop through the data copying each byte to the tty layer. */
 141                 tty_insert_flip_string(tty, data, urb->actual_length);
 142
 143                 /* Force the data to the tty layer. */
 144                 tty_flip_buffer_push(tty);
 145         }
 146         tty_kref_put(tty);
 147
 148         /* Set any port variables. */
 149         spin_lock_irqsave(&metro_priv->lock, flags);
 150         throttled = metro_priv->throttled;
 151         spin_unlock_irqrestore(&metro_priv->lock, flags);
 152
 153         /* Continue trying to read if set. */
 154         if (!throttled) {
 155                 usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
 156                                  usb_rcvintpipe(port->serial->dev, port->interrupt_in_endpointAddress),
 157                                  port->interrupt_in_urb->transfer_buffer,
 158                                  port->interrupt_in_urb->transfer_buffer_length,
 159                                  metrousb_read_int_callback, port, 1);
 160
 161                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 162
 163                 if (result)
 164                         dev_err(&port->dev,
 165                                 "%s - failed submitting interrupt in urb, error code=%d\n",
 166                                 __func__, result);
 167         }
 168         return;
 169
 170 exit:
 171         /* Try to resubmit the urb. */
 172         result = usb_submit_urb(urb, GFP_ATOMIC);
 173         if (result)
 174                 dev_err(&port->dev,
 175                         "%s - failed submitting interrupt in urb, error code=%d\n",
 176                         __func__, result);
 177 }
 178
 179 static void metrousb_write_int_callback(struct urb *urb)
 180 {
 181         struct usb_serial_port *port = urb->context;
 182
 183         dev_warn(&port->dev, "%s not implemented yet.\n",
 184                 __func__);
 185 }
 186
 187 static void metrousb_cleanup(struct usb_serial_port *port)
 188 {
 189         dev_dbg(&port->dev, "%s\n", __func__);
 190
 191         if (port->serial->dev) {
 192                 /* Shutdown any interrupt in urbs. */
 193                 if (port->interrupt_in_urb) {
 194                         usb_unlink_urb(port->interrupt_in_urb);
 195                         usb_kill_urb(port->interrupt_in_urb);
 196                 }
 197
 198                 /* Send deactivate cmd to device */
 199                 metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
 200         }
 201 }
 202
 203 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
 204 {
 205         struct usb_serial *serial = port->serial;
 206         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 207         unsigned long flags = 0;
 208         int result = 0;
 209
 210         dev_dbg(&port->dev, "%s\n", __func__);
 211
 212         /* Make sure the urb is initialized. */
 213         if (!port->interrupt_in_urb) {
 214                 dev_err(&port->dev, "%s - interrupt urb not initialized\n",
 215                         __func__);
 216                 return -ENODEV;
 217         }
 218
 219         /* Set the private data information for the port. */
 220         spin_lock_irqsave(&metro_priv->lock, flags);
 221         metro_priv->control_state = 0;
 222         metro_priv->throttled = 0;
 223         spin_unlock_irqrestore(&metro_priv->lock, flags);
 224
 225         /*
 226          * Force low_latency on so that our tty_push actually forces the data
 227          * through, otherwise it is scheduled, and with high data rates (like
 228          * with OHCI) data can get lost.
 229          */
 230         if (tty)
 231                 tty->low_latency = 1;
 232
 233         /* Clear the urb pipe. */
 234         usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
 235
 236         /* Start reading from the device */
 237         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 238                           usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 239                            port->interrupt_in_urb->transfer_buffer,
 240                            port->interrupt_in_urb->transfer_buffer_length,
 241                            metrousb_read_int_callback, port, 1);
 242         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 243
 244         if (result) {
 245                 dev_err(&port->dev,
 246                         "%s - failed submitting interrupt in urb, error code=%d\n",
 247                         __func__, result);
 248                 goto exit;
 249         }
 250
 251         /* Send activate cmd to device */
 252         result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
 253         if (result) {
 254                 dev_err(&port->dev,
 255                         "%s - failed to configure device for port number=%d, error code=%d\n",
 256                         __func__, port->number, result);
 257                 goto exit;
 258         }
 259
 260         dev_dbg(&port->dev, "%s - port open\n", __func__);
 261 exit:
 262         return result;
 263 }
 264
 265 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
 266 {
 267         int retval = 0;
 268         unsigned char mcr = METROUSB_MCR_NONE;
 269
 270         dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
 271                 __func__, control_state);
 272
 273         /* Set the modem control value. */
 274         if (control_state & TIOCM_DTR)
 275                 mcr |= METROUSB_MCR_DTR;
 276         if (control_state & TIOCM_RTS)
 277                 mcr |= METROUSB_MCR_RTS;
 278
 279         /* Send the command to the usb port. */
 280         retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 281                                 METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
 282                                 control_state, 0, NULL, 0, WDR_TIMEOUT);
 283         if (retval < 0)
 284                 dev_err(&serial->dev->dev,
 285                         "%s - set modem ctrl=0x%x failed, error code=%d\n",
 286                         __func__, mcr, retval);
 287
 288         return retval;
 289 }
 290
 291 static void metrousb_shutdown(struct usb_serial *serial)
 292 {
 293         int i = 0;
 294
 295         dev_dbg(&serial->dev->dev, "%s\n", __func__);
 296
 297         /* Stop reading and writing on all ports. */
 298         for (i = 0; i < serial->num_ports; ++i) {
 299                 /* Close any open urbs. */
 300                 metrousb_cleanup(serial->port[i]);
 301
 302                 /* Free memory. */
 303                 kfree(usb_get_serial_port_data(serial->port[i]));
 304                 usb_set_serial_port_data(serial->port[i], NULL);
 305
 306                 dev_dbg(&serial->dev->dev, "%s - freed port number=%d\n",
 307                         __func__, serial->port[i]->number);
 308         }
 309 }
 310
 311 static int metrousb_startup(struct usb_serial *serial)
 312 {
 313         struct metrousb_private *metro_priv;
 314         struct usb_serial_port *port;
 315         int i = 0;
 316
 317         dev_dbg(&serial->dev->dev, "%s\n", __func__);
 318
 319         /* Loop through the serial ports setting up the private structures.
 320          * Currently we only use one port. */
 321         for (i = 0; i < serial->num_ports; ++i) {
 322                 port = serial->port[i];
 323
 324                 /* Declare memory. */
 325                 metro_priv = kzalloc(sizeof(struct metrousb_private), GFP_KERNEL);
 326                 if (!metro_priv)
 327                         return -ENOMEM;
 328
 329                 /* Initialize memory. */
 330                 spin_lock_init(&metro_priv->lock);
 331                 usb_set_serial_port_data(port, metro_priv);
 332
 333                 dev_dbg(&serial->dev->dev, "%s - port number=%d\n ",
 334                         __func__, port->number);
 335         }
 336
 337         return 0;
 338 }
 339
 340 static void metrousb_throttle(struct tty_struct *tty)
 341 {
 342         struct usb_serial_port *port = tty->driver_data;
 343         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 344         unsigned long flags = 0;
 345
 346         dev_dbg(tty->dev, "%s\n", __func__);
 347
 348         /* Set the private information for the port to stop reading data. */
 349         spin_lock_irqsave(&metro_priv->lock, flags);
 350         metro_priv->throttled = 1;
 351         spin_unlock_irqrestore(&metro_priv->lock, flags);
 352 }
 353
 354 static int metrousb_tiocmget(struct tty_struct *tty)
 355 {
 356         unsigned long control_state = 0;
 357         struct usb_serial_port *port = tty->driver_data;
 358         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 359         unsigned long flags = 0;
 360
 361         dev_dbg(tty->dev, "%s\n", __func__);
 362
 363         spin_lock_irqsave(&metro_priv->lock, flags);
 364         control_state = metro_priv->control_state;
 365         spin_unlock_irqrestore(&metro_priv->lock, flags);
 366
 367         return control_state;
 368 }
 369
 370 static int metrousb_tiocmset(struct tty_struct *tty,
 371                              unsigned int set, unsigned int clear)
 372 {
 373         struct usb_serial_port *port = tty->driver_data;
 374         struct usb_serial *serial = port->serial;
 375         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 376         unsigned long flags = 0;
 377         unsigned long control_state = 0;
 378
 379         dev_dbg(tty->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
 380
 381         spin_lock_irqsave(&metro_priv->lock, flags);
 382         control_state = metro_priv->control_state;
 383
 384         /* Set the RTS and DTR values. */
 385         if (set & TIOCM_RTS)
 386                 control_state |= TIOCM_RTS;
 387         if (set & TIOCM_DTR)
 388                 control_state |= TIOCM_DTR;
 389         if (clear & TIOCM_RTS)
 390                 control_state &= ~TIOCM_RTS;
 391         if (clear & TIOCM_DTR)
 392                 control_state &= ~TIOCM_DTR;
 393
 394         metro_priv->control_state = control_state;
 395         spin_unlock_irqrestore(&metro_priv->lock, flags);
 396         return metrousb_set_modem_ctrl(serial, control_state);
 397 }
 398
 399 static void metrousb_unthrottle(struct tty_struct *tty)
 400 {
 401         struct usb_serial_port *port = tty->driver_data;
 402         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 403         unsigned long flags = 0;
 404         int result = 0;
 405
 406         dev_dbg(tty->dev, "%s\n", __func__);
 407
 408         /* Set the private information for the port to resume reading data. */
 409         spin_lock_irqsave(&metro_priv->lock, flags);
 410         metro_priv->throttled = 0;
 411         spin_unlock_irqrestore(&metro_priv->lock, flags);
 412
 413         /* Submit the urb to read from the port. */
 414         port->interrupt_in_urb->dev = port->serial->dev;
 415         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 416         if (result)
 417                 dev_err(tty->dev,
 418                         "failed submitting interrupt in urb error code=%d\n",
 419                         result);
 420 }
 421
 422 static struct usb_driver metrousb_driver = {
 423         .name =         "metro-usb",
 424         .probe =        usb_serial_probe,
 425         .disconnect =   usb_serial_disconnect,
 426         .id_table =     id_table
 427 };
 428
 429 static struct usb_serial_driver metrousb_device = {
 430         .driver = {
 431                 .owner =        THIS_MODULE,
 432                 .name =         "metro-usb",
 433         },
 434         .description            = "Metrologic USB to serial converter.",
 435         .id_table               = id_table,
 436         .num_ports              = 1,
 437         .open                   = metrousb_open,
 438         .close                  = metrousb_cleanup,
 439         .read_int_callback      = metrousb_read_int_callback,
 440         .write_int_callback     = metrousb_write_int_callback,
 441         .attach                 = metrousb_startup,
 442         .release                = metrousb_shutdown,
 443         .throttle               = metrousb_throttle,
 444         .unthrottle             = metrousb_unthrottle,
 445         .tiocmget               = metrousb_tiocmget,
 446         .tiocmset               = metrousb_tiocmset,
 447 };
 448
 449 static struct usb_serial_driver * const serial_drivers[] = {
 450         &metrousb_device,
 451         NULL,
 452 };
 453
 454 module_usb_serial_driver(metrousb_driver, serial_drivers);
 455
 456 MODULE_LICENSE("GPL");
 457 MODULE_AUTHOR("Philip Nicastro");
 458 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
 459 MODULE_DESCRIPTION(DRIVER_DESC);
 460
 461 /* Module input parameters */
 462 module_param(debug, bool, S_IRUGO | S_IWUSR);
 463 MODULE_PARM_DESC(debug, "Print debug info (bool 1=on, 0=off)");