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/tty.h>
  11 #include <linux/module.h>
  12 #include <linux/usb.h>
  13 #include <linux/errno.h>
  14 #include <linux/slab.h>
  15 #include <linux/tty_driver.h>
  16 #include <linux/tty_flip.h>
  17 #include <linux/moduleparam.h>
  18 #include <linux/spinlock.h>
  19 #include <linux/uaccess.h>
  20 #include <linux/usb/serial.h>
  21
  22 #define DRIVER_DESC "Metrologic Instruments Inc. - USB-POS driver"
  23
  24 /* Product information. */
  25 #define FOCUS_VENDOR_ID                 0x0C2E
  26 #define FOCUS_PRODUCT_ID_BI             0x0720
  27 #define FOCUS_PRODUCT_ID_UNI            0x0700
  28
  29 #define METROUSB_SET_REQUEST_TYPE       0x40
  30 #define METROUSB_SET_MODEM_CTRL_REQUEST 10
  31 #define METROUSB_SET_BREAK_REQUEST      0x40
  32 #define METROUSB_MCR_NONE               0x08    /* Deactivate DTR and RTS. */
  33 #define METROUSB_MCR_RTS                0x0a    /* Activate RTS. */
  34 #define METROUSB_MCR_DTR                0x09    /* Activate DTR. */
  35 #define WDR_TIMEOUT                     5000    /* default urb timeout. */
  36
  37 /* Private data structure. */
  38 struct metrousb_private {
  39         spinlock_t lock;
  40         int throttled;
  41         unsigned long control_state;
  42 };
  43
  44 /* Device table list. */
  45 static const struct usb_device_id id_table[] = {
  46         { USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_BI) },
  47         { USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_UNI) },
  48         { }, /* Terminating entry. */
  49 };
  50 MODULE_DEVICE_TABLE(usb, id_table);
  51
  52 /* UNI-Directional mode commands for device configure */
  53 #define UNI_CMD_OPEN    0x80
  54 #define UNI_CMD_CLOSE   0xFF
  55
  56 static inline int metrousb_is_unidirectional_mode(struct usb_serial_port *port)
  57 {
  58         __u16 product_id = le16_to_cpu(
  59                 port->serial->dev->descriptor.idProduct);
  60
  61         return product_id == FOCUS_PRODUCT_ID_UNI;
  62 }
  63
  64 static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
  65 {
  66         int ret;
  67         int actual_len;
  68         u8 *buffer_cmd = NULL;
  69
  70         if (!metrousb_is_unidirectional_mode(port))
  71                 return 0;
  72
  73         buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
  74         if (!buffer_cmd)
  75                 return -ENOMEM;
  76
  77         *buffer_cmd = cmd;
  78
  79         ret = usb_interrupt_msg(port->serial->dev,
  80                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
  81                 buffer_cmd, sizeof(cmd),
  82                 &actual_len, USB_CTRL_SET_TIMEOUT);
  83
  84         kfree(buffer_cmd);
  85
  86         if (ret < 0)
  87                 return ret;
  88         else if (actual_len != sizeof(cmd))
  89                 return -EIO;
  90         return 0;
  91 }
  92
  93 static void metrousb_read_int_callback(struct urb *urb)
  94 {
  95         struct usb_serial_port *port = urb->context;
  96         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
  97         unsigned char *data = urb->transfer_buffer;
  98         int throttled = 0;
  99         int result = 0;
 100         unsigned long flags = 0;
 101
 102         dev_dbg(&port->dev, "%s\n", __func__);
 103
 104         switch (urb->status) {
 105         case 0:
 106                 /* Success status, read from the port. */
 107                 break;
 108         case -ECONNRESET:
 109         case -ENOENT:
 110         case -ESHUTDOWN:
 111                 /* urb has been terminated. */
 112                 dev_dbg(&port->dev,
 113                         "%s - urb shutting down, error code=%d\n",
 114                         __func__, urb->status);
 115                 return;
 116         default:
 117                 dev_dbg(&port->dev,
 118                         "%s - non-zero urb received, error code=%d\n",
 119                         __func__, urb->status);
 120                 goto exit;
 121         }
 122
 123
 124         /* Set the data read from the usb port into the serial port buffer. */
 125         if (urb->actual_length) {
 126                 /* Loop through the data copying each byte to the tty layer. */
 127                 tty_insert_flip_string(&port->port, data, urb->actual_length);
 128
 129                 /* Force the data to the tty layer. */
 130                 tty_flip_buffer_push(&port->port);
 131         }
 132
 133         /* Set any port variables. */
 134         spin_lock_irqsave(&metro_priv->lock, flags);
 135         throttled = metro_priv->throttled;
 136         spin_unlock_irqrestore(&metro_priv->lock, flags);
 137
 138         /* Continue trying to read if set. */
 139         if (!throttled) {
 140                 usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
 141                                  usb_rcvintpipe(port->serial->dev, port->interrupt_in_endpointAddress),
 142                                  port->interrupt_in_urb->transfer_buffer,
 143                                  port->interrupt_in_urb->transfer_buffer_length,
 144                                  metrousb_read_int_callback, port, 1);
 145
 146                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 147
 148                 if (result)
 149                         dev_err(&port->dev,
 150                                 "%s - failed submitting interrupt in urb, error code=%d\n",
 151                                 __func__, result);
 152         }
 153         return;
 154
 155 exit:
 156         /* Try to resubmit the urb. */
 157         result = usb_submit_urb(urb, GFP_ATOMIC);
 158         if (result)
 159                 dev_err(&port->dev,
 160                         "%s - failed submitting interrupt in urb, error code=%d\n",
 161                         __func__, result);
 162 }
 163
 164 static void metrousb_write_int_callback(struct urb *urb)
 165 {
 166         struct usb_serial_port *port = urb->context;
 167
 168         dev_warn(&port->dev, "%s not implemented yet.\n",
 169                 __func__);
 170 }
 171
 172 static void metrousb_cleanup(struct usb_serial_port *port)
 173 {
 174         dev_dbg(&port->dev, "%s\n", __func__);
 175
 176         usb_unlink_urb(port->interrupt_in_urb);
 177         usb_kill_urb(port->interrupt_in_urb);
 178
 179         metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
 180 }
 181
 182 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
 183 {
 184         struct usb_serial *serial = port->serial;
 185         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 186         unsigned long flags = 0;
 187         int result = 0;
 188
 189         dev_dbg(&port->dev, "%s\n", __func__);
 190
 191         /* Make sure the urb is initialized. */
 192         if (!port->interrupt_in_urb) {
 193                 dev_err(&port->dev, "%s - interrupt urb not initialized\n",
 194                         __func__);
 195                 return -ENODEV;
 196         }
 197
 198         /* Set the private data information for the port. */
 199         spin_lock_irqsave(&metro_priv->lock, flags);
 200         metro_priv->control_state = 0;
 201         metro_priv->throttled = 0;
 202         spin_unlock_irqrestore(&metro_priv->lock, flags);
 203
 204         /* Clear the urb pipe. */
 205         usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
 206
 207         /* Start reading from the device */
 208         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 209                           usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 210                            port->interrupt_in_urb->transfer_buffer,
 211                            port->interrupt_in_urb->transfer_buffer_length,
 212                            metrousb_read_int_callback, port, 1);
 213         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 214
 215         if (result) {
 216                 dev_err(&port->dev,
 217                         "%s - failed submitting interrupt in urb, error code=%d\n",
 218                         __func__, result);
 219                 goto exit;
 220         }
 221
 222         /* Send activate cmd to device */
 223         result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
 224         if (result) {
 225                 dev_err(&port->dev,
 226                         "%s - failed to configure device, error code=%d\n",
 227                         __func__, result);
 228                 goto exit;
 229         }
 230
 231         dev_dbg(&port->dev, "%s - port open\n", __func__);
 232 exit:
 233         return result;
 234 }
 235
 236 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
 237 {
 238         int retval = 0;
 239         unsigned char mcr = METROUSB_MCR_NONE;
 240
 241         dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
 242                 __func__, control_state);
 243
 244         /* Set the modem control value. */
 245         if (control_state & TIOCM_DTR)
 246                 mcr |= METROUSB_MCR_DTR;
 247         if (control_state & TIOCM_RTS)
 248                 mcr |= METROUSB_MCR_RTS;
 249
 250         /* Send the command to the usb port. */
 251         retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 252                                 METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
 253                                 control_state, 0, NULL, 0, WDR_TIMEOUT);
 254         if (retval < 0)
 255                 dev_err(&serial->dev->dev,
 256                         "%s - set modem ctrl=0x%x failed, error code=%d\n",
 257                         __func__, mcr, retval);
 258
 259         return retval;
 260 }
 261
 262 static int metrousb_port_probe(struct usb_serial_port *port)
 263 {
 264         struct metrousb_private *metro_priv;
 265
 266         metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
 267         if (!metro_priv)
 268                 return -ENOMEM;
 269
 270         spin_lock_init(&metro_priv->lock);
 271
 272         usb_set_serial_port_data(port, metro_priv);
 273
 274         return 0;
 275 }
 276
 277 static int metrousb_port_remove(struct usb_serial_port *port)
 278 {
 279         struct metrousb_private *metro_priv;
 280
 281         metro_priv = usb_get_serial_port_data(port);
 282         kfree(metro_priv);
 283
 284         return 0;
 285 }
 286
 287 static void metrousb_throttle(struct tty_struct *tty)
 288 {
 289         struct usb_serial_port *port = tty->driver_data;
 290         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 291         unsigned long flags = 0;
 292
 293         dev_dbg(tty->dev, "%s\n", __func__);
 294
 295         /* Set the private information for the port to stop reading data. */
 296         spin_lock_irqsave(&metro_priv->lock, flags);
 297         metro_priv->throttled = 1;
 298         spin_unlock_irqrestore(&metro_priv->lock, flags);
 299 }
 300
 301 static int metrousb_tiocmget(struct tty_struct *tty)
 302 {
 303         unsigned long control_state = 0;
 304         struct usb_serial_port *port = tty->driver_data;
 305         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 306         unsigned long flags = 0;
 307
 308         dev_dbg(tty->dev, "%s\n", __func__);
 309
 310         spin_lock_irqsave(&metro_priv->lock, flags);
 311         control_state = metro_priv->control_state;
 312         spin_unlock_irqrestore(&metro_priv->lock, flags);
 313
 314         return control_state;
 315 }
 316
 317 static int metrousb_tiocmset(struct tty_struct *tty,
 318                              unsigned int set, unsigned int clear)
 319 {
 320         struct usb_serial_port *port = tty->driver_data;
 321         struct usb_serial *serial = port->serial;
 322         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 323         unsigned long flags = 0;
 324         unsigned long control_state = 0;
 325
 326         dev_dbg(tty->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
 327
 328         spin_lock_irqsave(&metro_priv->lock, flags);
 329         control_state = metro_priv->control_state;
 330
 331         /* Set the RTS and DTR values. */
 332         if (set & TIOCM_RTS)
 333                 control_state |= TIOCM_RTS;
 334         if (set & TIOCM_DTR)
 335                 control_state |= TIOCM_DTR;
 336         if (clear & TIOCM_RTS)
 337                 control_state &= ~TIOCM_RTS;
 338         if (clear & TIOCM_DTR)
 339                 control_state &= ~TIOCM_DTR;
 340
 341         metro_priv->control_state = control_state;
 342         spin_unlock_irqrestore(&metro_priv->lock, flags);
 343         return metrousb_set_modem_ctrl(serial, control_state);
 344 }
 345
 346 static void metrousb_unthrottle(struct tty_struct *tty)
 347 {
 348         struct usb_serial_port *port = tty->driver_data;
 349         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 350         unsigned long flags = 0;
 351         int result = 0;
 352
 353         dev_dbg(tty->dev, "%s\n", __func__);
 354
 355         /* Set the private information for the port to resume reading data. */
 356         spin_lock_irqsave(&metro_priv->lock, flags);
 357         metro_priv->throttled = 0;
 358         spin_unlock_irqrestore(&metro_priv->lock, flags);
 359
 360         /* Submit the urb to read from the port. */
 361         port->interrupt_in_urb->dev = port->serial->dev;
 362         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 363         if (result)
 364                 dev_err(tty->dev,
 365                         "failed submitting interrupt in urb error code=%d\n",
 366                         result);
 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",
 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         .write_int_callback     = metrousb_write_int_callback,
 381         .port_probe             = metrousb_port_probe,
 382         .port_remove            = metrousb_port_remove,
 383         .throttle               = metrousb_throttle,
 384         .unthrottle             = metrousb_unthrottle,
 385         .tiocmget               = metrousb_tiocmget,
 386         .tiocmset               = metrousb_tiocmset,
 387 };
 388
 389 static struct usb_serial_driver * const serial_drivers[] = {
 390         &metrousb_device,
 391         NULL,
 392 };
 393
 394 module_usb_serial_driver(serial_drivers, id_table);
 395
 396 MODULE_LICENSE("GPL");
 397 MODULE_AUTHOR("Philip Nicastro");
 398 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
 399 MODULE_DESCRIPTION(DRIVER_DESC);