drivers/usb/serial/metro-usb.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3   Some of this code is credited to Linux USB open source files that are
   4   distributed with Linux.
   5
   6   Copyright:    2007 Metrologic Instruments. All rights reserved.
   7   Copyright:    2011 Azimut Ltd. <http://azimutrzn.ru/>
   8 */
   9
  10 #include <linux/kernel.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 const 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         { USB_DEVICE_INTERFACE_CLASS(0x0c2e, 0x0730, 0xff) },   /* MS7820 */
  50         { }, /* Terminating entry. */
  51 };
  52 MODULE_DEVICE_TABLE(usb, id_table);
  53
  54 /* UNI-Directional mode commands for device configure */
  55 #define UNI_CMD_OPEN    0x80
  56 #define UNI_CMD_CLOSE   0xFF
  57
  58 static int metrousb_is_unidirectional_mode(struct usb_serial *serial)
  59 {
  60         u16 product_id = le16_to_cpu(serial->dev->descriptor.idProduct);
  61
  62         return product_id == FOCUS_PRODUCT_ID_UNI;
  63 }
  64
  65 static int metrousb_calc_num_ports(struct usb_serial *serial,
  66                                    struct usb_serial_endpoints *epds)
  67 {
  68         if (metrousb_is_unidirectional_mode(serial)) {
  69                 if (epds->num_interrupt_out == 0) {
  70                         dev_err(&serial->interface->dev, "interrupt-out endpoint missing\n");
  71                         return -ENODEV;
  72                 }
  73         }
  74
  75         return 1;
  76 }
  77
  78 static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
  79 {
  80         int ret;
  81         int actual_len;
  82         u8 *buffer_cmd = NULL;
  83
  84         if (!metrousb_is_unidirectional_mode(port->serial))
  85                 return 0;
  86
  87         buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
  88         if (!buffer_cmd)
  89                 return -ENOMEM;
  90
  91         *buffer_cmd = cmd;
  92
  93         ret = usb_interrupt_msg(port->serial->dev,
  94                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
  95                 buffer_cmd, sizeof(cmd),
  96                 &actual_len, USB_CTRL_SET_TIMEOUT);
  97
  98         kfree(buffer_cmd);
  99
 100         if (ret < 0)
 101                 return ret;
 102         else if (actual_len != sizeof(cmd))
 103                 return -EIO;
 104         return 0;
 105 }
 106
 107 static void metrousb_read_int_callback(struct urb *urb)
 108 {
 109         struct usb_serial_port *port = urb->context;
 110         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 111         unsigned char *data = urb->transfer_buffer;
 112         unsigned long flags;
 113         int throttled = 0;
 114         int result = 0;
 115
 116         dev_dbg(&port->dev, "%s\n", __func__);
 117
 118         switch (urb->status) {
 119         case 0:
 120                 /* Success status, read from the port. */
 121                 break;
 122         case -ECONNRESET:
 123         case -ENOENT:
 124         case -ESHUTDOWN:
 125                 /* urb has been terminated. */
 126                 dev_dbg(&port->dev,
 127                         "%s - urb shutting down, error code=%d\n",
 128                         __func__, urb->status);
 129                 return;
 130         default:
 131                 dev_dbg(&port->dev,
 132                         "%s - non-zero urb received, error code=%d\n",
 133                         __func__, urb->status);
 134                 goto exit;
 135         }
 136
 137
 138         /* Set the data read from the usb port into the serial port buffer. */
 139         if (urb->actual_length) {
 140                 /* Loop through the data copying each byte to the tty layer. */
 141                 tty_insert_flip_string(&port->port, data, urb->actual_length);
 142
 143                 /* Force the data to the tty layer. */
 144                 tty_flip_buffer_push(&port->port);
 145         }
 146
 147         /* Set any port variables. */
 148         spin_lock_irqsave(&metro_priv->lock, flags);
 149         throttled = metro_priv->throttled;
 150         spin_unlock_irqrestore(&metro_priv->lock, flags);
 151
 152         if (throttled)
 153                 return;
 154 exit:
 155         /* Try to resubmit the urb. */
 156         result = usb_submit_urb(urb, GFP_ATOMIC);
 157         if (result)
 158                 dev_err(&port->dev,
 159                         "%s - failed submitting interrupt in urb, error code=%d\n",
 160                         __func__, result);
 161 }
 162
 163 static void metrousb_cleanup(struct usb_serial_port *port)
 164 {
 165         usb_kill_urb(port->interrupt_in_urb);
 166
 167         metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
 168 }
 169
 170 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
 171 {
 172         struct usb_serial *serial = port->serial;
 173         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 174         unsigned long flags;
 175         int result = 0;
 176
 177         /* Set the private data information for the port. */
 178         spin_lock_irqsave(&metro_priv->lock, flags);
 179         metro_priv->control_state = 0;
 180         metro_priv->throttled = 0;
 181         spin_unlock_irqrestore(&metro_priv->lock, flags);
 182
 183         /* Clear the urb pipe. */
 184         usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
 185
 186         /* Start reading from the device */
 187         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 188                           usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 189                            port->interrupt_in_urb->transfer_buffer,
 190                            port->interrupt_in_urb->transfer_buffer_length,
 191                            metrousb_read_int_callback, port, 1);
 192         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 193
 194         if (result) {
 195                 dev_err(&port->dev,
 196                         "%s - failed submitting interrupt in urb, error code=%d\n",
 197                         __func__, result);
 198                 return result;
 199         }
 200
 201         /* Send activate cmd to device */
 202         result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
 203         if (result) {
 204                 dev_err(&port->dev,
 205                         "%s - failed to configure device, error code=%d\n",
 206                         __func__, result);
 207                 goto err_kill_urb;
 208         }
 209
 210         return 0;
 211
 212 err_kill_urb:
 213         usb_kill_urb(port->interrupt_in_urb);
 214
 215         return result;
 216 }
 217
 218 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
 219 {
 220         int retval = 0;
 221         unsigned char mcr = METROUSB_MCR_NONE;
 222
 223         dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
 224                 __func__, control_state);
 225
 226         /* Set the modem control value. */
 227         if (control_state & TIOCM_DTR)
 228                 mcr |= METROUSB_MCR_DTR;
 229         if (control_state & TIOCM_RTS)
 230                 mcr |= METROUSB_MCR_RTS;
 231
 232         /* Send the command to the usb port. */
 233         retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 234                                 METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
 235                                 control_state, 0, NULL, 0, WDR_TIMEOUT);
 236         if (retval < 0)
 237                 dev_err(&serial->dev->dev,
 238                         "%s - set modem ctrl=0x%x failed, error code=%d\n",
 239                         __func__, mcr, retval);
 240
 241         return retval;
 242 }
 243
 244 static int metrousb_port_probe(struct usb_serial_port *port)
 245 {
 246         struct metrousb_private *metro_priv;
 247
 248         metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
 249         if (!metro_priv)
 250                 return -ENOMEM;
 251
 252         spin_lock_init(&metro_priv->lock);
 253
 254         usb_set_serial_port_data(port, metro_priv);
 255
 256         return 0;
 257 }
 258
 259 static void metrousb_port_remove(struct usb_serial_port *port)
 260 {
 261         struct metrousb_private *metro_priv;
 262
 263         metro_priv = usb_get_serial_port_data(port);
 264         kfree(metro_priv);
 265 }
 266
 267 static void metrousb_throttle(struct tty_struct *tty)
 268 {
 269         struct usb_serial_port *port = tty->driver_data;
 270         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 271         unsigned long flags;
 272
 273         /* Set the private information for the port to stop reading data. */
 274         spin_lock_irqsave(&metro_priv->lock, flags);
 275         metro_priv->throttled = 1;
 276         spin_unlock_irqrestore(&metro_priv->lock, flags);
 277 }
 278
 279 static int metrousb_tiocmget(struct tty_struct *tty)
 280 {
 281         unsigned long control_state = 0;
 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;
 285
 286         spin_lock_irqsave(&metro_priv->lock, flags);
 287         control_state = metro_priv->control_state;
 288         spin_unlock_irqrestore(&metro_priv->lock, flags);
 289
 290         return control_state;
 291 }
 292
 293 static int metrousb_tiocmset(struct tty_struct *tty,
 294                              unsigned int set, unsigned int clear)
 295 {
 296         struct usb_serial_port *port = tty->driver_data;
 297         struct usb_serial *serial = port->serial;
 298         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 299         unsigned long flags;
 300         unsigned long control_state = 0;
 301
 302         dev_dbg(&port->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
 303
 304         spin_lock_irqsave(&metro_priv->lock, flags);
 305         control_state = metro_priv->control_state;
 306
 307         /* Set the RTS and DTR values. */
 308         if (set & TIOCM_RTS)
 309                 control_state |= TIOCM_RTS;
 310         if (set & TIOCM_DTR)
 311                 control_state |= TIOCM_DTR;
 312         if (clear & TIOCM_RTS)
 313                 control_state &= ~TIOCM_RTS;
 314         if (clear & TIOCM_DTR)
 315                 control_state &= ~TIOCM_DTR;
 316
 317         metro_priv->control_state = control_state;
 318         spin_unlock_irqrestore(&metro_priv->lock, flags);
 319         return metrousb_set_modem_ctrl(serial, control_state);
 320 }
 321
 322 static void metrousb_unthrottle(struct tty_struct *tty)
 323 {
 324         struct usb_serial_port *port = tty->driver_data;
 325         struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
 326         unsigned long flags;
 327         int result = 0;
 328
 329         /* Set the private information for the port to resume reading data. */
 330         spin_lock_irqsave(&metro_priv->lock, flags);
 331         metro_priv->throttled = 0;
 332         spin_unlock_irqrestore(&metro_priv->lock, flags);
 333
 334         /* Submit the urb to read from the port. */
 335         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 336         if (result)
 337                 dev_err(&port->dev,
 338                         "failed submitting interrupt in urb error code=%d\n",
 339                         result);
 340 }
 341
 342 static struct usb_serial_driver metrousb_device = {
 343         .driver = {
 344                 .owner =        THIS_MODULE,
 345                 .name =         "metro-usb",
 346         },
 347         .description            = "Metrologic USB to Serial",
 348         .id_table               = id_table,
 349         .num_interrupt_in       = 1,
 350         .calc_num_ports         = metrousb_calc_num_ports,
 351         .open                   = metrousb_open,
 352         .close                  = metrousb_cleanup,
 353         .read_int_callback      = metrousb_read_int_callback,
 354         .port_probe             = metrousb_port_probe,
 355         .port_remove            = metrousb_port_remove,
 356         .throttle               = metrousb_throttle,
 357         .unthrottle             = metrousb_unthrottle,
 358         .tiocmget               = metrousb_tiocmget,
 359         .tiocmset               = metrousb_tiocmset,
 360 };
 361
 362 static struct usb_serial_driver * const serial_drivers[] = {
 363         &metrousb_device,
 364         NULL,
 365 };
 366
 367 module_usb_serial_driver(serial_drivers, id_table);
 368
 369 MODULE_LICENSE("GPL v2");
 370 MODULE_AUTHOR("Philip Nicastro");
 371 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
 372 MODULE_DESCRIPTION(DRIVER_DESC);