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         if (throttled)
 139                 return;
 140 exit:
 141         /* Try to resubmit the urb. */
 142         result = usb_submit_urb(urb, GFP_ATOMIC);
 143         if (result)
 144                 dev_err(&port->dev,
 145                         "%s - failed submitting interrupt in urb, error code=%d\n",
 146                         __func__, result);
 147 }
 148
 149 static void metrousb_cleanup(struct usb_serial_port *port)
 150 {
 151         usb_kill_urb(port->interrupt_in_urb);
 152
 153         metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
 154 }
 155
 156 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
 157 {
 158         struct usb_serial *serial = port->serial;
 159         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 160         unsigned long flags = 0;
 161         int result = 0;
 162
 163         /* Make sure the urb is initialized. */
 164         if (!port->interrupt_in_urb) {
 165                 dev_err(&port->dev, "%s - interrupt urb not initialized\n",
 166                         __func__);
 167                 return -ENODEV;
 168         }
 169
 170         /* Set the private data information for the port. */
 171         spin_lock_irqsave(&metro_priv->lock, flags);
 172         metro_priv->control_state = 0;
 173         metro_priv->throttled = 0;
 174         spin_unlock_irqrestore(&metro_priv->lock, flags);
 175
 176         /* Clear the urb pipe. */
 177         usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
 178
 179         /* Start reading from the device */
 180         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 181                           usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 182                            port->interrupt_in_urb->transfer_buffer,
 183                            port->interrupt_in_urb->transfer_buffer_length,
 184                            metrousb_read_int_callback, port, 1);
 185         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 186
 187         if (result) {
 188                 dev_err(&port->dev,
 189                         "%s - failed submitting interrupt in urb, error code=%d\n",
 190                         __func__, result);
 191                 goto exit;
 192         }
 193
 194         /* Send activate cmd to device */
 195         result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
 196         if (result) {
 197                 dev_err(&port->dev,
 198                         "%s - failed to configure device, error code=%d\n",
 199                         __func__, result);
 200                 goto exit;
 201         }
 202 exit:
 203         return result;
 204 }
 205
 206 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
 207 {
 208         int retval = 0;
 209         unsigned char mcr = METROUSB_MCR_NONE;
 210
 211         dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
 212                 __func__, control_state);
 213
 214         /* Set the modem control value. */
 215         if (control_state & TIOCM_DTR)
 216                 mcr |= METROUSB_MCR_DTR;
 217         if (control_state & TIOCM_RTS)
 218                 mcr |= METROUSB_MCR_RTS;
 219
 220         /* Send the command to the usb port. */
 221         retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 222                                 METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
 223                                 control_state, 0, NULL, 0, WDR_TIMEOUT);
 224         if (retval < 0)
 225                 dev_err(&serial->dev->dev,
 226                         "%s - set modem ctrl=0x%x failed, error code=%d\n",
 227                         __func__, mcr, retval);
 228
 229         return retval;
 230 }
 231
 232 static int metrousb_port_probe(struct usb_serial_port *port)
 233 {
 234         struct metrousb_private *metro_priv;
 235
 236         metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
 237         if (!metro_priv)
 238                 return -ENOMEM;
 239
 240         spin_lock_init(&metro_priv->lock);
 241
 242         usb_set_serial_port_data(port, metro_priv);
 243
 244         return 0;
 245 }
 246
 247 static int metrousb_port_remove(struct usb_serial_port *port)
 248 {
 249         struct metrousb_private *metro_priv;
 250
 251         metro_priv = usb_get_serial_port_data(port);
 252         kfree(metro_priv);
 253
 254         return 0;
 255 }
 256
 257 static void metrousb_throttle(struct tty_struct *tty)
 258 {
 259         struct usb_serial_port *port = tty->driver_data;
 260         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 261         unsigned long flags = 0;
 262
 263         /* Set the private information for the port to stop reading data. */
 264         spin_lock_irqsave(&metro_priv->lock, flags);
 265         metro_priv->throttled = 1;
 266         spin_unlock_irqrestore(&metro_priv->lock, flags);
 267 }
 268
 269 static int metrousb_tiocmget(struct tty_struct *tty)
 270 {
 271         unsigned long control_state = 0;
 272         struct usb_serial_port *port = tty->driver_data;
 273         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 274         unsigned long flags = 0;
 275
 276         spin_lock_irqsave(&metro_priv->lock, flags);
 277         control_state = metro_priv->control_state;
 278         spin_unlock_irqrestore(&metro_priv->lock, flags);
 279
 280         return control_state;
 281 }
 282
 283 static int metrousb_tiocmset(struct tty_struct *tty,
 284                              unsigned int set, unsigned int clear)
 285 {
 286         struct usb_serial_port *port = tty->driver_data;
 287         struct usb_serial *serial = port->serial;
 288         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 289         unsigned long flags = 0;
 290         unsigned long control_state = 0;
 291
 292         dev_dbg(tty->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
 293
 294         spin_lock_irqsave(&metro_priv->lock, flags);
 295         control_state = metro_priv->control_state;
 296
 297         /* Set the RTS and DTR values. */
 298         if (set & TIOCM_RTS)
 299                 control_state |= TIOCM_RTS;
 300         if (set & TIOCM_DTR)
 301                 control_state |= TIOCM_DTR;
 302         if (clear & TIOCM_RTS)
 303                 control_state &= ~TIOCM_RTS;
 304         if (clear & TIOCM_DTR)
 305                 control_state &= ~TIOCM_DTR;
 306
 307         metro_priv->control_state = control_state;
 308         spin_unlock_irqrestore(&metro_priv->lock, flags);
 309         return metrousb_set_modem_ctrl(serial, control_state);
 310 }
 311
 312 static void metrousb_unthrottle(struct tty_struct *tty)
 313 {
 314         struct usb_serial_port *port = tty->driver_data;
 315         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 316         unsigned long flags = 0;
 317         int result = 0;
 318
 319         /* Set the private information for the port to resume reading data. */
 320         spin_lock_irqsave(&metro_priv->lock, flags);
 321         metro_priv->throttled = 0;
 322         spin_unlock_irqrestore(&metro_priv->lock, flags);
 323
 324         /* Submit the urb to read from the port. */
 325         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 326         if (result)
 327                 dev_err(tty->dev,
 328                         "failed submitting interrupt in urb error code=%d\n",
 329                         result);
 330 }
 331
 332 static struct usb_serial_driver metrousb_device = {
 333         .driver = {
 334                 .owner =        THIS_MODULE,
 335                 .name =         "metro-usb",
 336         },
 337         .description            = "Metrologic USB to Serial",
 338         .id_table               = id_table,
 339         .num_ports              = 1,
 340         .open                   = metrousb_open,
 341         .close                  = metrousb_cleanup,
 342         .read_int_callback      = metrousb_read_int_callback,
 343         .port_probe             = metrousb_port_probe,
 344         .port_remove            = metrousb_port_remove,
 345         .throttle               = metrousb_throttle,
 346         .unthrottle             = metrousb_unthrottle,
 347         .tiocmget               = metrousb_tiocmget,
 348         .tiocmset               = metrousb_tiocmset,
 349 };
 350
 351 static struct usb_serial_driver * const serial_drivers[] = {
 352         &metrousb_device,
 353         NULL,
 354 };
 355
 356 module_usb_serial_driver(serial_drivers, id_table);
 357
 358 MODULE_LICENSE("GPL");
 359 MODULE_AUTHOR("Philip Nicastro");
 360 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
 361 MODULE_DESCRIPTION(DRIVER_DESC);