drivers/usb/serial/ssu100.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * usb-serial driver for Quatech SSU-100
   4  *
   5  * based on ftdi_sio.c and the original serqt_usb.c from Quatech
   6  *
   7  */
   8
   9 #include <linux/errno.h>
  10 #include <linux/slab.h>
  11 #include <linux/tty.h>
  12 #include <linux/tty_driver.h>
  13 #include <linux/tty_flip.h>
  14 #include <linux/module.h>
  15 #include <linux/serial.h>
  16 #include <linux/usb.h>
  17 #include <linux/usb/serial.h>
  18 #include <linux/serial_reg.h>
  19 #include <linux/uaccess.h>
  20
  21 #define QT_OPEN_CLOSE_CHANNEL       0xca
  22 #define QT_SET_GET_DEVICE           0xc2
  23 #define QT_SET_GET_REGISTER         0xc0
  24 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
  25 #define QT_SET_ATF                  0xcd
  26 #define QT_GET_SET_UART             0xc1
  27 #define QT_TRANSFER_IN              0xc0
  28 #define QT_HW_FLOW_CONTROL_MASK     0xc5
  29 #define QT_SW_FLOW_CONTROL_MASK     0xc6
  30
  31 #define  SERIAL_MSR_MASK            0xf0
  32
  33 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
  34
  35 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
  36
  37 #define  MAX_BAUD_RATE              460800
  38
  39 #define ATC_DISABLED                0x00
  40 #define DUPMODE_BITS        0xc0
  41 #define RR_BITS             0x03
  42 #define LOOPMODE_BITS       0x41
  43 #define RS232_MODE          0x00
  44 #define RTSCTS_TO_CONNECTOR 0x40
  45 #define CLKS_X4             0x02
  46 #define FULLPWRBIT          0x00000080
  47 #define NEXT_BOARD_POWER_BIT        0x00000004
  48
  49 #define DRIVER_DESC "Quatech SSU-100 USB to Serial Driver"
  50
  51 #define USB_VENDOR_ID_QUATECH   0x061d  /* Quatech VID */
  52 #define QUATECH_SSU100  0xC020  /* SSU100 */
  53
  54 static const struct usb_device_id id_table[] = {
  55         {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU100)},
  56         {}                      /* Terminating entry */
  57 };
  58 MODULE_DEVICE_TABLE(usb, id_table);
  59
  60 struct ssu100_port_private {
  61         spinlock_t status_lock;
  62         u8 shadowLSR;
  63         u8 shadowMSR;
  64 };
  65
  66 static inline int ssu100_control_msg(struct usb_device *dev,
  67                                      u8 request, u16 data, u16 index)
  68 {
  69         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
  70                                request, 0x40, data, index,
  71                                NULL, 0, 300);
  72 }
  73
  74 static inline int ssu100_setdevice(struct usb_device *dev, u8 *data)
  75 {
  76         u16 x = ((u16)(data[1] << 8) | (u16)(data[0]));
  77
  78         return ssu100_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
  79 }
  80
  81
  82 static inline int ssu100_getdevice(struct usb_device *dev, u8 *data)
  83 {
  84         int ret;
  85
  86         ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
  87                               QT_SET_GET_DEVICE, 0xc0, 0, 0,
  88                               data, 3, 300);
  89         if (ret < 3) {
  90                 if (ret >= 0)
  91                         ret = -EIO;
  92         }
  93
  94         return ret;
  95 }
  96
  97 static inline int ssu100_getregister(struct usb_device *dev,
  98                                      unsigned short uart,
  99                                      unsigned short reg,
 100                                      u8 *data)
 101 {
 102         int ret;
 103
 104         ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 105                               QT_SET_GET_REGISTER, 0xc0, reg,
 106                               uart, data, sizeof(*data), 300);
 107         if (ret < (int)sizeof(*data)) {
 108                 if (ret >= 0)
 109                         ret = -EIO;
 110         }
 111
 112         return ret;
 113 }
 114
 115
 116 static inline int ssu100_setregister(struct usb_device *dev,
 117                                      unsigned short uart,
 118                                      unsigned short reg,
 119                                      u16 data)
 120 {
 121         u16 value = (data << 8) | reg;
 122
 123         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 124                                QT_SET_GET_REGISTER, 0x40, value, uart,
 125                                NULL, 0, 300);
 126
 127 }
 128
 129 #define set_mctrl(dev, set)             update_mctrl((dev), (set), 0)
 130 #define clear_mctrl(dev, clear) update_mctrl((dev), 0, (clear))
 131
 132 /* these do not deal with device that have more than 1 port */
 133 static inline int update_mctrl(struct usb_device *dev, unsigned int set,
 134                                unsigned int clear)
 135 {
 136         unsigned urb_value;
 137         int result;
 138
 139         if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
 140                 dev_dbg(&dev->dev, "%s - DTR|RTS not being set|cleared\n", __func__);
 141                 return 0;       /* no change */
 142         }
 143
 144         clear &= ~set;  /* 'set' takes precedence over 'clear' */
 145         urb_value = 0;
 146         if (set & TIOCM_DTR)
 147                 urb_value |= UART_MCR_DTR;
 148         if (set & TIOCM_RTS)
 149                 urb_value |= UART_MCR_RTS;
 150
 151         result = ssu100_setregister(dev, 0, UART_MCR, urb_value);
 152         if (result < 0)
 153                 dev_dbg(&dev->dev, "%s Error from MODEM_CTRL urb\n", __func__);
 154
 155         return result;
 156 }
 157
 158 static int ssu100_initdevice(struct usb_device *dev)
 159 {
 160         u8 *data;
 161         int result = 0;
 162
 163         data = kzalloc(3, GFP_KERNEL);
 164         if (!data)
 165                 return -ENOMEM;
 166
 167         result = ssu100_getdevice(dev, data);
 168         if (result < 0) {
 169                 dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
 170                 goto out;
 171         }
 172
 173         data[1] &= ~FULLPWRBIT;
 174
 175         result = ssu100_setdevice(dev, data);
 176         if (result < 0) {
 177                 dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
 178                 goto out;
 179         }
 180
 181         result = ssu100_control_msg(dev, QT_GET_SET_PREBUF_TRIG_LVL, 128, 0);
 182         if (result < 0) {
 183                 dev_dbg(&dev->dev, "%s - set prebuffer level failed %i\n", __func__, result);
 184                 goto out;
 185         }
 186
 187         result = ssu100_control_msg(dev, QT_SET_ATF, ATC_DISABLED, 0);
 188         if (result < 0) {
 189                 dev_dbg(&dev->dev, "%s - set ATFprebuffer level failed %i\n", __func__, result);
 190                 goto out;
 191         }
 192
 193         result = ssu100_getdevice(dev, data);
 194         if (result < 0) {
 195                 dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
 196                 goto out;
 197         }
 198
 199         data[0] &= ~(RR_BITS | DUPMODE_BITS);
 200         data[0] |= CLKS_X4;
 201         data[1] &= ~(LOOPMODE_BITS);
 202         data[1] |= RS232_MODE;
 203
 204         result = ssu100_setdevice(dev, data);
 205         if (result < 0) {
 206                 dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
 207                 goto out;
 208         }
 209
 210 out:    kfree(data);
 211         return result;
 212
 213 }
 214
 215
 216 static void ssu100_set_termios(struct tty_struct *tty,
 217                                struct usb_serial_port *port,
 218                                const struct ktermios *old_termios)
 219 {
 220         struct usb_device *dev = port->serial->dev;
 221         struct ktermios *termios = &tty->termios;
 222         u16 baud, divisor, remainder;
 223         unsigned int cflag = termios->c_cflag;
 224         u16 urb_value = 0; /* will hold the new flags */
 225         int result;
 226
 227         if (cflag & PARENB) {
 228                 if (cflag & PARODD)
 229                         urb_value |= UART_LCR_PARITY;
 230                 else
 231                         urb_value |= SERIAL_EVEN_PARITY;
 232         }
 233
 234         urb_value |= UART_LCR_WLEN(tty_get_char_size(cflag));
 235
 236         baud = tty_get_baud_rate(tty);
 237         if (!baud)
 238                 baud = 9600;
 239
 240         dev_dbg(&port->dev, "%s - got baud = %d\n", __func__, baud);
 241
 242
 243         divisor = MAX_BAUD_RATE / baud;
 244         remainder = MAX_BAUD_RATE % baud;
 245         if (((remainder * 2) >= baud) && (baud != 110))
 246                 divisor++;
 247
 248         urb_value = urb_value << 8;
 249
 250         result = ssu100_control_msg(dev, QT_GET_SET_UART, divisor, urb_value);
 251         if (result < 0)
 252                 dev_dbg(&port->dev, "%s - set uart failed\n", __func__);
 253
 254         if (cflag & CRTSCTS)
 255                 result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
 256                                             SERIAL_CRTSCTS, 0);
 257         else
 258                 result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
 259                                             0, 0);
 260         if (result < 0)
 261                 dev_dbg(&port->dev, "%s - set HW flow control failed\n", __func__);
 262
 263         if (I_IXOFF(tty) || I_IXON(tty)) {
 264                 u16 x = ((u16)(START_CHAR(tty) << 8) | (u16)(STOP_CHAR(tty)));
 265
 266                 result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
 267                                             x, 0);
 268         } else
 269                 result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
 270                                             0, 0);
 271
 272         if (result < 0)
 273                 dev_dbg(&port->dev, "%s - set SW flow control failed\n", __func__);
 274
 275 }
 276
 277
 278 static int ssu100_open(struct tty_struct *tty, struct usb_serial_port *port)
 279 {
 280         struct usb_device *dev = port->serial->dev;
 281         struct ssu100_port_private *priv = usb_get_serial_port_data(port);
 282         u8 *data;
 283         int result;
 284         unsigned long flags;
 285
 286         data = kzalloc(2, GFP_KERNEL);
 287         if (!data)
 288                 return -ENOMEM;
 289
 290         result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 291                                  QT_OPEN_CLOSE_CHANNEL,
 292                                  QT_TRANSFER_IN, 0x01,
 293                                  0, data, 2, 300);
 294         if (result < 2) {
 295                 dev_dbg(&port->dev, "%s - open failed %i\n", __func__, result);
 296                 if (result >= 0)
 297                         result = -EIO;
 298                 kfree(data);
 299                 return result;
 300         }
 301
 302         spin_lock_irqsave(&priv->status_lock, flags);
 303         priv->shadowLSR = data[0];
 304         priv->shadowMSR = data[1];
 305         spin_unlock_irqrestore(&priv->status_lock, flags);
 306
 307         kfree(data);
 308
 309 /* set to 9600 */
 310         result = ssu100_control_msg(dev, QT_GET_SET_UART, 0x30, 0x0300);
 311         if (result < 0)
 312                 dev_dbg(&port->dev, "%s - set uart failed\n", __func__);
 313
 314         if (tty)
 315                 ssu100_set_termios(tty, port, &tty->termios);
 316
 317         return usb_serial_generic_open(tty, port);
 318 }
 319
 320 static int ssu100_attach(struct usb_serial *serial)
 321 {
 322         return ssu100_initdevice(serial->dev);
 323 }
 324
 325 static int ssu100_port_probe(struct usb_serial_port *port)
 326 {
 327         struct ssu100_port_private *priv;
 328
 329         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 330         if (!priv)
 331                 return -ENOMEM;
 332
 333         spin_lock_init(&priv->status_lock);
 334
 335         usb_set_serial_port_data(port, priv);
 336
 337         return 0;
 338 }
 339
 340 static void ssu100_port_remove(struct usb_serial_port *port)
 341 {
 342         struct ssu100_port_private *priv;
 343
 344         priv = usb_get_serial_port_data(port);
 345         kfree(priv);
 346 }
 347
 348 static int ssu100_tiocmget(struct tty_struct *tty)
 349 {
 350         struct usb_serial_port *port = tty->driver_data;
 351         struct usb_device *dev = port->serial->dev;
 352         u8 *d;
 353         int r;
 354
 355         d = kzalloc(2, GFP_KERNEL);
 356         if (!d)
 357                 return -ENOMEM;
 358
 359         r = ssu100_getregister(dev, 0, UART_MCR, d);
 360         if (r < 0)
 361                 goto mget_out;
 362
 363         r = ssu100_getregister(dev, 0, UART_MSR, d+1);
 364         if (r < 0)
 365                 goto mget_out;
 366
 367         r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
 368                 (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
 369                 (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
 370                 (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
 371                 (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
 372                 (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
 373
 374 mget_out:
 375         kfree(d);
 376         return r;
 377 }
 378
 379 static int ssu100_tiocmset(struct tty_struct *tty,
 380                            unsigned int set, unsigned int clear)
 381 {
 382         struct usb_serial_port *port = tty->driver_data;
 383         struct usb_device *dev = port->serial->dev;
 384
 385         return update_mctrl(dev, set, clear);
 386 }
 387
 388 static void ssu100_dtr_rts(struct usb_serial_port *port, int on)
 389 {
 390         struct usb_device *dev = port->serial->dev;
 391
 392         /* Disable flow control */
 393         if (!on) {
 394                 if (ssu100_setregister(dev, 0, UART_MCR, 0) < 0)
 395                         dev_err(&port->dev, "error from flowcontrol urb\n");
 396         }
 397         /* drop RTS and DTR */
 398         if (on)
 399                 set_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
 400         else
 401                 clear_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
 402 }
 403
 404 static void ssu100_update_msr(struct usb_serial_port *port, u8 msr)
 405 {
 406         struct ssu100_port_private *priv = usb_get_serial_port_data(port);
 407         unsigned long flags;
 408
 409         spin_lock_irqsave(&priv->status_lock, flags);
 410         priv->shadowMSR = msr;
 411         spin_unlock_irqrestore(&priv->status_lock, flags);
 412
 413         if (msr & UART_MSR_ANY_DELTA) {
 414                 /* update input line counters */
 415                 if (msr & UART_MSR_DCTS)
 416                         port->icount.cts++;
 417                 if (msr & UART_MSR_DDSR)
 418                         port->icount.dsr++;
 419                 if (msr & UART_MSR_DDCD)
 420                         port->icount.dcd++;
 421                 if (msr & UART_MSR_TERI)
 422                         port->icount.rng++;
 423                 wake_up_interruptible(&port->port.delta_msr_wait);
 424         }
 425 }
 426
 427 static void ssu100_update_lsr(struct usb_serial_port *port, u8 lsr,
 428                               char *tty_flag)
 429 {
 430         struct ssu100_port_private *priv = usb_get_serial_port_data(port);
 431         unsigned long flags;
 432
 433         spin_lock_irqsave(&priv->status_lock, flags);
 434         priv->shadowLSR = lsr;
 435         spin_unlock_irqrestore(&priv->status_lock, flags);
 436
 437         *tty_flag = TTY_NORMAL;
 438         if (lsr & UART_LSR_BRK_ERROR_BITS) {
 439                 /* we always want to update icount, but we only want to
 440                  * update tty_flag for one case */
 441                 if (lsr & UART_LSR_BI) {
 442                         port->icount.brk++;
 443                         *tty_flag = TTY_BREAK;
 444                         usb_serial_handle_break(port);
 445                 }
 446                 if (lsr & UART_LSR_PE) {
 447                         port->icount.parity++;
 448                         if (*tty_flag == TTY_NORMAL)
 449                                 *tty_flag = TTY_PARITY;
 450                 }
 451                 if (lsr & UART_LSR_FE) {
 452                         port->icount.frame++;
 453                         if (*tty_flag == TTY_NORMAL)
 454                                 *tty_flag = TTY_FRAME;
 455                 }
 456                 if (lsr & UART_LSR_OE) {
 457                         port->icount.overrun++;
 458                         tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
 459                 }
 460         }
 461
 462 }
 463
 464 static void ssu100_process_read_urb(struct urb *urb)
 465 {
 466         struct usb_serial_port *port = urb->context;
 467         char *packet = urb->transfer_buffer;
 468         char flag = TTY_NORMAL;
 469         u32 len = urb->actual_length;
 470         int i;
 471         char *ch;
 472
 473         if ((len >= 4) &&
 474             (packet[0] == 0x1b) && (packet[1] == 0x1b) &&
 475             ((packet[2] == 0x00) || (packet[2] == 0x01))) {
 476                 if (packet[2] == 0x00)
 477                         ssu100_update_lsr(port, packet[3], &flag);
 478                 if (packet[2] == 0x01)
 479                         ssu100_update_msr(port, packet[3]);
 480
 481                 len -= 4;
 482                 ch = packet + 4;
 483         } else
 484                 ch = packet;
 485
 486         if (!len)
 487                 return; /* status only */
 488
 489         if (port->sysrq) {
 490                 for (i = 0; i < len; i++, ch++) {
 491                         if (!usb_serial_handle_sysrq_char(port, *ch))
 492                                 tty_insert_flip_char(&port->port, *ch, flag);
 493                 }
 494         } else {
 495                 tty_insert_flip_string_fixed_flag(&port->port, ch, flag, len);
 496         }
 497
 498         tty_flip_buffer_push(&port->port);
 499 }
 500
 501 static struct usb_serial_driver ssu100_device = {
 502         .driver = {
 503                 .name = "ssu100",
 504         },
 505         .description         = DRIVER_DESC,
 506         .id_table            = id_table,
 507         .num_ports           = 1,
 508         .open                = ssu100_open,
 509         .attach              = ssu100_attach,
 510         .port_probe          = ssu100_port_probe,
 511         .port_remove         = ssu100_port_remove,
 512         .dtr_rts             = ssu100_dtr_rts,
 513         .process_read_urb    = ssu100_process_read_urb,
 514         .tiocmget            = ssu100_tiocmget,
 515         .tiocmset            = ssu100_tiocmset,
 516         .tiocmiwait          = usb_serial_generic_tiocmiwait,
 517         .get_icount          = usb_serial_generic_get_icount,
 518         .set_termios         = ssu100_set_termios,
 519 };
 520
 521 static struct usb_serial_driver * const serial_drivers[] = {
 522         &ssu100_device, NULL
 523 };
 524
 525 module_usb_serial_driver(serial_drivers, id_table);
 526
 527 MODULE_DESCRIPTION(DRIVER_DESC);
 528 MODULE_LICENSE("GPL v2");