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