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 #define DRIVER_DESC "Metrologic Instruments Inc. - USB-POS driver"
  24
  25 /* Product information. */
  26 #define FOCUS_VENDOR_ID                 0x0C2E
  27 #define FOCUS_PRODUCT_ID_BI             0x0720
  28 #define FOCUS_PRODUCT_ID_UNI            0x0700
  29
  30 #define METROUSB_SET_REQUEST_TYPE       0x40
  31 #define METROUSB_SET_MODEM_CTRL_REQUEST 10
  32 #define METROUSB_SET_BREAK_REQUEST      0x40
  33 #define METROUSB_MCR_NONE               0x08    /* Deactivate DTR and RTS. */
  34 #define METROUSB_MCR_RTS                0x0a    /* Activate RTS. */
  35 #define METROUSB_MCR_DTR                0x09    /* Activate DTR. */
  36 #define WDR_TIMEOUT                     5000    /* default urb timeout. */
  37
  38 /* Private data structure. */
  39 struct metrousb_private {
  40         spinlock_t lock;
  41         int throttled;
  42         unsigned long control_state;
  43 };
  44
  45 /* Device table list. */
  46 static struct usb_device_id id_table[] = {
  47         { USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_BI) },
  48         { USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_UNI) },
  49         { }, /* Terminating entry. */
  50 };
  51 MODULE_DEVICE_TABLE(usb, id_table);
  52
  53 /* UNI-Directional mode commands for device configure */
  54 #define UNI_CMD_OPEN    0x80
  55 #define UNI_CMD_CLOSE   0xFF
  56
  57 inline int metrousb_is_unidirectional_mode(struct usb_serial_port *port)
  58 {
  59         __u16 product_id = le16_to_cpu(
  60                 port->serial->dev->descriptor.idProduct);
  61
  62         return product_id == FOCUS_PRODUCT_ID_UNI;
  63 }
  64
  65 static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
  66 {
  67         int ret;
  68         int actual_len;
  69         u8 *buffer_cmd = NULL;
  70
  71         if (!metrousb_is_unidirectional_mode(port))
  72                 return 0;
  73
  74         buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
  75         if (!buffer_cmd)
  76                 return -ENOMEM;
  77
  78         *buffer_cmd = cmd;
  79
  80         ret = usb_interrupt_msg(port->serial->dev,
  81                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
  82                 buffer_cmd, sizeof(cmd),
  83                 &actual_len, USB_CTRL_SET_TIMEOUT);
  84
  85         kfree(buffer_cmd);
  86
  87         if (ret < 0)
  88                 return ret;
  89         else if (actual_len != sizeof(cmd))
  90                 return -EIO;
  91         return 0;
  92 }
  93
  94 static void metrousb_read_int_callback(struct urb *urb)
  95 {
  96         struct usb_serial_port *port = urb->context;
  97         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
  98         unsigned char *data = urb->transfer_buffer;
  99         int throttled = 0;
 100         int result = 0;
 101         unsigned long flags = 0;
 102
 103         dev_dbg(&port->dev, "%s\n", __func__);
 104
 105         switch (urb->status) {
 106         case 0:
 107                 /* Success status, read from the port. */
 108                 break;
 109         case -ECONNRESET:
 110         case -ENOENT:
 111         case -ESHUTDOWN:
 112                 /* urb has been terminated. */
 113                 dev_dbg(&port->dev,
 114                         "%s - urb shutting down, error code=%d\n",
 115                         __func__, urb->status);
 116                 return;
 117         default:
 118                 dev_dbg(&port->dev,
 119                         "%s - non-zero urb received, error code=%d\n",
 120                         __func__, urb->status);
 121                 goto exit;
 122         }
 123
 124
 125         /* Set the data read from the usb port into the serial port buffer. */
 126         if (urb->actual_length) {
 127                 /* Loop through the data copying each byte to the tty layer. */
 128                 tty_insert_flip_string(&port->port, data, urb->actual_length);
 129
 130                 /* Force the data to the tty layer. */
 131                 tty_flip_buffer_push(&port->port);
 132         }
 133
 134         /* Set any port variables. */
 135         spin_lock_irqsave(&metro_priv->lock, flags);
 136         throttled = metro_priv->throttled;
 137         spin_unlock_irqrestore(&metro_priv->lock, flags);
 138
 139         /* Continue trying to read if set. */
 140         if (!throttled) {
 141                 usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
 142                                  usb_rcvintpipe(port->serial->dev, port->interrupt_in_endpointAddress),
 143                                  port->interrupt_in_urb->transfer_buffer,
 144                                  port->interrupt_in_urb->transfer_buffer_length,
 145                                  metrousb_read_int_callback, port, 1);
 146
 147                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 148
 149                 if (result)
 150                         dev_err(&port->dev,
 151                                 "%s - failed submitting interrupt in urb, error code=%d\n",
 152                                 __func__, result);
 153         }
 154         return;
 155
 156 exit:
 157         /* Try to resubmit the urb. */
 158         result = usb_submit_urb(urb, GFP_ATOMIC);
 159         if (result)
 160                 dev_err(&port->dev,
 161                         "%s - failed submitting interrupt in urb, error code=%d\n",
 162                         __func__, result);
 163 }
 164
 165 static void metrousb_write_int_callback(struct urb *urb)
 166 {
 167         struct usb_serial_port *port = urb->context;
 168
 169         dev_warn(&port->dev, "%s not implemented yet.\n",
 170                 __func__);
 171 }
 172
 173 static void metrousb_cleanup(struct usb_serial_port *port)
 174 {
 175         dev_dbg(&port->dev, "%s\n", __func__);
 176
 177         usb_unlink_urb(port->interrupt_in_urb);
 178         usb_kill_urb(port->interrupt_in_urb);
 179
 180         metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
 181 }
 182
 183 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
 184 {
 185         struct usb_serial *serial = port->serial;
 186         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 187         unsigned long flags = 0;
 188         int result = 0;
 189
 190         dev_dbg(&port->dev, "%s\n", __func__);
 191
 192         /* Make sure the urb is initialized. */
 193         if (!port->interrupt_in_urb) {
 194                 dev_err(&port->dev, "%s - interrupt urb not initialized\n",
 195                         __func__);
 196                 return -ENODEV;
 197         }
 198
 199         /* Set the private data information for the port. */
 200         spin_lock_irqsave(&metro_priv->lock, flags);
 201         metro_priv->control_state = 0;
 202         metro_priv->throttled = 0;
 203         spin_unlock_irqrestore(&metro_priv->lock, flags);
 204
 205         /* Clear the urb pipe. */
 206         usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
 207
 208         /* Start reading from the device */
 209         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 210                           usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 211                            port->interrupt_in_urb->transfer_buffer,
 212                            port->interrupt_in_urb->transfer_buffer_length,
 213                            metrousb_read_int_callback, port, 1);
 214         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 215
 216         if (result) {
 217                 dev_err(&port->dev,
 218                         "%s - failed submitting interrupt in urb, error code=%d\n",
 219                         __func__, result);
 220                 goto exit;
 221         }
 222
 223         /* Send activate cmd to device */
 224         result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
 225         if (result) {
 226                 dev_err(&port->dev,
 227                         "%s - failed to configure device, error code=%d\n",
 228                         __func__, result);
 229                 goto exit;
 230         }
 231
 232         dev_dbg(&port->dev, "%s - port open\n", __func__);
 233 exit:
 234         return result;
 235 }
 236
 237 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
 238 {
 239         int retval = 0;
 240         unsigned char mcr = METROUSB_MCR_NONE;
 241
 242         dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
 243                 __func__, control_state);
 244
 245         /* Set the modem control value. */
 246         if (control_state & TIOCM_DTR)
 247                 mcr |= METROUSB_MCR_DTR;
 248         if (control_state & TIOCM_RTS)
 249                 mcr |= METROUSB_MCR_RTS;
 250
 251         /* Send the command to the usb port. */
 252         retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 253                                 METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
 254                                 control_state, 0, NULL, 0, WDR_TIMEOUT);
 255         if (retval < 0)
 256                 dev_err(&serial->dev->dev,
 257                         "%s - set modem ctrl=0x%x failed, error code=%d\n",
 258                         __func__, mcr, retval);
 259
 260         return retval;
 261 }
 262
 263 static int metrousb_port_probe(struct usb_serial_port *port)
 264 {
 265         struct metrousb_private *metro_priv;
 266
 267         metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
 268         if (!metro_priv)
 269                 return -ENOMEM;
 270
 271         spin_lock_init(&metro_priv->lock);
 272
 273         usb_set_serial_port_data(port, metro_priv);
 274
 275         return 0;
 276 }
 277
 278 static int metrousb_port_remove(struct usb_serial_port *port)
 279 {
 280         struct metrousb_private *metro_priv;
 281
 282         metro_priv = usb_get_serial_port_data(port);
 283         kfree(metro_priv);
 284
 285         return 0;
 286 }
 287
 288 static void metrousb_throttle(struct tty_struct *tty)
 289 {
 290         struct usb_serial_port *port = tty->driver_data;
 291         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 292         unsigned long flags = 0;
 293
 294         dev_dbg(tty->dev, "%s\n", __func__);
 295
 296         /* Set the private information for the port to stop reading data. */
 297         spin_lock_irqsave(&metro_priv->lock, flags);
 298         metro_priv->throttled = 1;
 299         spin_unlock_irqrestore(&metro_priv->lock, flags);
 300 }
 301
 302 static int metrousb_tiocmget(struct tty_struct *tty)
 303 {
 304         unsigned long control_state = 0;
 305         struct usb_serial_port *port = tty->driver_data;
 306         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 307         unsigned long flags = 0;
 308
 309         dev_dbg(tty->dev, "%s\n", __func__);
 310
 311         spin_lock_irqsave(&metro_priv->lock, flags);
 312         control_state = metro_priv->control_state;
 313         spin_unlock_irqrestore(&metro_priv->lock, flags);
 314
 315         return control_state;
 316 }
 317
 318 static int metrousb_tiocmset(struct tty_struct *tty,
 319                              unsigned int set, unsigned int clear)
 320 {
 321         struct usb_serial_port *port = tty->driver_data;
 322         struct usb_serial *serial = port->serial;
 323         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 324         unsigned long flags = 0;
 325         unsigned long control_state = 0;
 326
 327         dev_dbg(tty->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
 328
 329         spin_lock_irqsave(&metro_priv->lock, flags);
 330         control_state = metro_priv->control_state;
 331
 332         /* Set the RTS and DTR values. */
 333         if (set & TIOCM_RTS)
 334                 control_state |= TIOCM_RTS;
 335         if (set & TIOCM_DTR)
 336                 control_state |= TIOCM_DTR;
 337         if (clear & TIOCM_RTS)
 338                 control_state &= ~TIOCM_RTS;
 339         if (clear & TIOCM_DTR)
 340                 control_state &= ~TIOCM_DTR;
 341
 342         metro_priv->control_state = control_state;
 343         spin_unlock_irqrestore(&metro_priv->lock, flags);
 344         return metrousb_set_modem_ctrl(serial, control_state);
 345 }
 346
 347 static void metrousb_unthrottle(struct tty_struct *tty)
 348 {
 349         struct usb_serial_port *port = tty->driver_data;
 350         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 351         unsigned long flags = 0;
 352         int result = 0;
 353
 354         dev_dbg(tty->dev, "%s\n", __func__);
 355
 356         /* Set the private information for the port to resume reading data. */
 357         spin_lock_irqsave(&metro_priv->lock, flags);
 358         metro_priv->throttled = 0;
 359         spin_unlock_irqrestore(&metro_priv->lock, flags);
 360
 361         /* Submit the urb to read from the port. */
 362         port->interrupt_in_urb->dev = port->serial->dev;
 363         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 364         if (result)
 365                 dev_err(tty->dev,
 366                         "failed submitting interrupt in urb error code=%d\n",
 367                         result);
 368 }
 369
 370 static struct usb_serial_driver metrousb_device = {
 371         .driver = {
 372                 .owner =        THIS_MODULE,
 373                 .name =         "metro-usb",
 374         },
 375         .description            = "Metrologic USB to Serial",
 376         .id_table               = id_table,
 377         .num_ports              = 1,
 378         .open                   = metrousb_open,
 379         .close                  = metrousb_cleanup,
 380         .read_int_callback      = metrousb_read_int_callback,
 381         .write_int_callback     = metrousb_write_int_callback,
 382         .port_probe             = metrousb_port_probe,
 383         .port_remove            = metrousb_port_remove,
 384         .throttle               = metrousb_throttle,
 385         .unthrottle             = metrousb_unthrottle,
 386         .tiocmget               = metrousb_tiocmget,
 387         .tiocmset               = metrousb_tiocmset,
 388 };
 389
 390 static struct usb_serial_driver * const serial_drivers[] = {
 391         &metrousb_device,
 392         NULL,
 393 };
 394
 395 module_usb_serial_driver(serial_drivers, id_table);
 396
 397 MODULE_LICENSE("GPL");
 398 MODULE_AUTHOR("Philip Nicastro");
 399 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
 400 MODULE_DESCRIPTION(DRIVER_DESC);