drivers/usb/serial/cp210x-stlink.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Silicon Laboratories CP210x USB to RS232 serial adaptor driver
   4  *
   5  * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
   6  *
   7  * Support to set flow control line levels using TIOCMGET and TIOCMSET
   8  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
   9  * control thanks to Munir Nassar nassarmu@real-time.com
  10  *
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/slab.h>
  16 #include <linux/tty.h>
  17 #include <linux/tty_flip.h>
  18 #include <linux/module.h>
  19 #include <linux/moduleparam.h>
  20 #include <linux/usb.h>
  21 #include <linux/uaccess.h>
  22 #include <linux/usb/serial.h>
  23
  24 #define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
  25
  26 /*
  27  * Function Prototypes
  28  */
  29 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
  30 static void cp210x_close(struct usb_serial_port *);
  31 static int cp210x_ioctl(struct tty_struct *tty,
  32         unsigned int cmd, unsigned long arg);
  33 static void cp210x_get_termios(struct tty_struct *, struct usb_serial_port *);
  34 static void cp210x_get_termios_port(struct usb_serial_port *port,
  35         tcflag_t *cflagp, unsigned int *baudp);
  36 static void cp210x_change_speed(struct tty_struct *, struct usb_serial_port *,
  37                                                         struct ktermios *);
  38 static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
  39                                                         struct ktermios*);
  40 static bool cp210x_tx_empty(struct usb_serial_port *port);
  41 static int cp210x_tiocmget(struct tty_struct *);
  42 static int cp210x_tiocmset(struct tty_struct *, unsigned int, unsigned int);
  43 static int cp210x_tiocmset_port(struct usb_serial_port *port,
  44                 unsigned int, unsigned int);
  45 static void cp210x_break_ctl(struct tty_struct *, int);
  46 static int cp210x_port_probe(struct usb_serial_port *);
  47 static void cp210x_port_remove(struct usb_serial_port *);
  48 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
  49
  50 static const struct usb_device_id id_table[] = {
  51         { USB_DEVICE(0x04E8, 0x20C6) }, /* SmartThings link WW (Zigbee Only) */
  52         { USB_DEVICE(0x04E8, 0x20C7) }, /* SmartThings link US */
  53         { USB_DEVICE(0x04E8, 0x20C8) }, /* SmartThings link EU */
  54         { USB_DEVICE(0x04E8, 0x20C9) }, /* SmartThings link KR */
  55         { } /* Terminating Entry */
  56 };
  57
  58 MODULE_DEVICE_TABLE(usb, id_table);
  59
  60 struct cp210x_port_private {
  61         __u8                    bPartNumber;
  62         __u8                    bInterfaceNumber;
  63         bool                    has_swapped_line_ctl;
  64         bool                    is_cp2102n_a01;
  65 };
  66
  67 static struct usb_serial_driver cp210x_device = {
  68         .driver = {
  69                 .owner =        THIS_MODULE,
  70                 .name =         "cp210x",
  71         },
  72         .id_table               = id_table,
  73         .num_ports              = 1,
  74         .bulk_in_size           = 256,
  75         .bulk_out_size          = 256,
  76         .open                   = cp210x_open,
  77         .close                  = cp210x_close,
  78         .ioctl                  = cp210x_ioctl,
  79         .break_ctl              = cp210x_break_ctl,
  80         .set_termios            = cp210x_set_termios,
  81         .tx_empty               = cp210x_tx_empty,
  82         .tiocmget               = cp210x_tiocmget,
  83         .tiocmset               = cp210x_tiocmset,
  84         .port_probe             = cp210x_port_probe,
  85         .port_remove            = cp210x_port_remove,
  86         .dtr_rts                = cp210x_dtr_rts
  87 };
  88
  89 /* IOCTLs */
  90 #define IOCTL_GPIOGET           0x8000
  91 #define IOCTL_GPIOSET           0x8001
  92
  93 static struct usb_serial_driver * const serial_drivers[] = {
  94         &cp210x_device, NULL
  95 };
  96
  97 /* Config request types */
  98 #define REQTYPE_HOST_TO_INTERFACE       0x41
  99 #define REQTYPE_INTERFACE_TO_HOST       0xc1
 100 #define REQTYPE_HOST_TO_DEVICE  0x40
 101 #define REQTYPE_DEVICE_TO_HOST  0xc0
 102
 103 /* Config request codes */
 104 #define CP210X_IFC_ENABLE       0x00
 105 #define CP210X_SET_BAUDDIV      0x01
 106 #define CP210X_GET_BAUDDIV      0x02
 107 #define CP210X_SET_LINE_CTL     0x03
 108 #define CP210X_GET_LINE_CTL     0x04
 109 #define CP210X_SET_BREAK        0x05
 110 #define CP210X_IMM_CHAR         0x06
 111 #define CP210X_SET_MHS          0x07
 112 #define CP210X_GET_MDMSTS       0x08
 113 #define CP210X_SET_XON          0x09
 114 #define CP210X_SET_XOFF         0x0A
 115 #define CP210X_SET_EVENTMASK    0x0B
 116 #define CP210X_GET_EVENTMASK    0x0C
 117 #define CP210X_SET_CHAR         0x0D
 118 #define CP210X_GET_CHARS        0x0E
 119 #define CP210X_GET_PROPS        0x0F
 120 #define CP210X_GET_COMM_STATUS  0x10
 121 #define CP210X_RESET            0x11
 122 #define CP210X_PURGE            0x12
 123 #define CP210X_SET_FLOW         0x13
 124 #define CP210X_GET_FLOW         0x14
 125 #define CP210X_EMBED_EVENTS     0x15
 126 #define CP210X_GET_EVENTSTATE   0x16
 127 #define CP210X_SET_CHARS        0x19
 128 #define CP210X_GET_BAUDRATE     0x1D
 129 #define CP210X_SET_BAUDRATE     0x1E
 130 #define CP210X_VENDOR_SPECIFIC  0xFF
 131
 132 /* CP210X_IFC_ENABLE */
 133 #define UART_ENABLE             0x0001
 134 #define UART_DISABLE            0x0000
 135
 136 /* CP210X_(SET|GET)_BAUDDIV */
 137 #define BAUD_RATE_GEN_FREQ      0x384000
 138
 139 /* CP210X_(SET|GET)_LINE_CTL */
 140 #define BITS_DATA_MASK          0X0f00
 141 #define BITS_DATA_5             0X0500
 142 #define BITS_DATA_6             0X0600
 143 #define BITS_DATA_7             0X0700
 144 #define BITS_DATA_8             0X0800
 145 #define BITS_DATA_9             0X0900
 146
 147 #define BITS_PARITY_MASK        0x00f0
 148 #define BITS_PARITY_NONE        0x0000
 149 #define BITS_PARITY_ODD         0x0010
 150 #define BITS_PARITY_EVEN        0x0020
 151 #define BITS_PARITY_MARK        0x0030
 152 #define BITS_PARITY_SPACE       0x0040
 153
 154 #define BITS_STOP_MASK          0x000f
 155 #define BITS_STOP_1             0x0000
 156 #define BITS_STOP_1_5           0x0001
 157 #define BITS_STOP_2             0x0002
 158
 159 /* CP210X_SET_BREAK */
 160 #define BREAK_ON                0x0001
 161 #define BREAK_OFF               0x0000
 162
 163 /* CP210X_(SET_MHS|GET_MDMSTS) */
 164 #define CONTROL_DTR             0x0001
 165 #define CONTROL_RTS             0x0002
 166 #define CONTROL_CTS             0x0010
 167 #define CONTROL_DSR             0x0020
 168 #define CONTROL_RING            0x0040
 169 #define CONTROL_DCD             0x0080
 170 #define CONTROL_WRITE_DTR       0x0100
 171 #define CONTROL_WRITE_RTS       0x0200
 172
 173 /* CP210X_VENDOR_SPECIFIC sub-commands passed in wValue */
 174 #define CP210X_WRITE_LATCH      0x37E1
 175 #define CP210X_READ_LATCH       0x00C2
 176 #define CP210X_GET_PARTNUM      0x370B
 177 #define CP2102N_GET_FW_VERS 0x0010
 178
 179 /* CP210X_GET_PARTNUM returns one of these */
 180 #define CP2101_PARTNUM          0x01
 181 #define CP2102_PARTNUM          0x02
 182 #define CP2103_PARTNUM          0x03
 183 #define CP2104_PARTNUM          0x04
 184 #define CP2105_PARTNUM          0x05
 185 #define CP2108_PARTNUM          0x08
 186 #define CP210x_PARTNUM_CP2102N_QFN28    0x20
 187 #define CP210x_PARTNUM_CP2102N_QFN24    0x21
 188 #define CP210x_PARTNUM_CP2102N_QFN20    0x22
 189
 190 /* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
 191 struct cp210x_comm_status {
 192         __le32   ulErrors;
 193         __le32   ulHoldReasons;
 194         __le32   ulAmountInInQueue;
 195         __le32   ulAmountInOutQueue;
 196         u8       bEofReceived;
 197         u8       bWaitForImmediate;
 198         u8       bReserved;
 199 } __packed;
 200
 201 /*
 202  * CP210X_PURGE - 16 bits passed in wValue of USB request.
 203  * SiLabs app note AN571 gives a strange description of the 4 bits:
 204  * bit 0 or bit 2 clears the transmit queue and 1 or 3 receive.
 205  * writing 1 to all, however, purges cp2108 well enough to avoid the hang.
 206  */
 207 #define PURGE_ALL               0x000f
 208
 209 /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
 210 struct cp210x_flow_ctl {
 211         __le32  ulControlHandshake;
 212         __le32  ulFlowReplace;
 213         __le32  ulXonLimit;
 214         __le32  ulXoffLimit;
 215 } __packed;
 216
 217 /* cp210x_flow_ctl::ulControlHandshake */
 218 #define CP210X_SERIAL_DTR_MASK          GENMASK(1, 0)
 219 #define CP210X_SERIAL_DTR_SHIFT(_mode)  (_mode)
 220 #define CP210X_SERIAL_CTS_HANDSHAKE     BIT(3)
 221 #define CP210X_SERIAL_DSR_HANDSHAKE     BIT(4)
 222 #define CP210X_SERIAL_DCD_HANDSHAKE     BIT(5)
 223 #define CP210X_SERIAL_DSR_SENSITIVITY   BIT(6)
 224
 225 /* values for cp210x_flow_ctl::ulControlHandshake::CP210X_SERIAL_DTR_MASK */
 226 #define CP210X_SERIAL_DTR_INACTIVE      0
 227 #define CP210X_SERIAL_DTR_ACTIVE        1
 228 #define CP210X_SERIAL_DTR_FLOW_CTL      2
 229
 230 /* cp210x_flow_ctl::ulFlowReplace */
 231 #define CP210X_SERIAL_AUTO_TRANSMIT     BIT(0)
 232 #define CP210X_SERIAL_AUTO_RECEIVE      BIT(1)
 233 #define CP210X_SERIAL_ERROR_CHAR        BIT(2)
 234 #define CP210X_SERIAL_NULL_STRIPPING    BIT(3)
 235 #define CP210X_SERIAL_BREAK_CHAR        BIT(4)
 236 #define CP210X_SERIAL_RTS_MASK          GENMASK(7, 6)
 237 #define CP210X_SERIAL_RTS_SHIFT(_mode)  (_mode << 6)
 238 #define CP210X_SERIAL_XOFF_CONTINUE     BIT(31)
 239
 240 /* values for cp210x_flow_ctl::ulFlowReplace::CP210X_SERIAL_RTS_MASK */
 241 #define CP210X_SERIAL_RTS_INACTIVE      0
 242 #define CP210X_SERIAL_RTS_ACTIVE        1
 243 #define CP210X_SERIAL_RTS_FLOW_CTL      2
 244
 245 /*
 246  * Reads a variable-sized block of CP210X_ registers, identified by req.
 247  * Returns data into buf in native USB byte order.
 248  */
 249 static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
 250                 void *buf, int bufsize)
 251 {
 252         struct usb_serial *serial = port->serial;
 253         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 254         void *dmabuf;
 255         int result;
 256
 257         dmabuf = kmalloc(bufsize, GFP_KERNEL);
 258         if (!dmabuf) {
 259                 /*
 260                  * FIXME Some callers don't bother to check for error,
 261                  * at least give them consistent junk until they are fixed
 262                  */
 263                 memset(buf, 0, bufsize);
 264                 return -ENOMEM;
 265         }
 266
 267         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 268                         req, REQTYPE_INTERFACE_TO_HOST, 0,
 269                         port_priv->bInterfaceNumber, dmabuf, bufsize,
 270                         USB_CTRL_SET_TIMEOUT);
 271         if (result == bufsize) {
 272                 memcpy(buf, dmabuf, bufsize);
 273                 result = 0;
 274         } else {
 275                 dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
 276                                 req, bufsize, result);
 277                 if (result >= 0)
 278                         result = -EPROTO;
 279
 280                 /*
 281                  * FIXME Some callers don't bother to check for error,
 282                  * at least give them consistent junk until they are fixed
 283                  */
 284                 memset(buf, 0, bufsize);
 285         }
 286
 287         kfree(dmabuf);
 288
 289         return result;
 290 }
 291
 292 /*
 293  * Reads any 32-bit CP210X_ register identified by req.
 294  */
 295 static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
 296 {
 297         __le32 le32_val;
 298         int err;
 299
 300         err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
 301         if (err) {
 302                 /*
 303                  * FIXME Some callers don't bother to check for error,
 304                  * at least give them consistent junk until they are fixed
 305                  */
 306                 *val = 0;
 307                 return err;
 308         }
 309
 310         *val = le32_to_cpu(le32_val);
 311
 312         return 0;
 313 }
 314
 315 /*
 316  * Reads any 16-bit CP210X_ register identified by req.
 317  */
 318 static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
 319 {
 320         __le16 le16_val;
 321         int err;
 322
 323         err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));
 324         if (err)
 325                 return err;
 326
 327         *val = le16_to_cpu(le16_val);
 328
 329         return 0;
 330 }
 331
 332 /*
 333  * Reads any 8-bit CP210X_ register identified by req.
 334  */
 335 static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
 336 {
 337         return cp210x_read_reg_block(port, req, val, sizeof(*val));
 338 }
 339
 340 /*
 341  * Writes any 16-bit CP210X_ register (req) whose value is passed
 342  * entirely in the wValue field of the USB request.
 343  */
 344 static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
 345 {
 346         struct usb_serial *serial = port->serial;
 347         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 348         int result;
 349
 350         result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 351                         req, REQTYPE_HOST_TO_INTERFACE, val,
 352                         port_priv->bInterfaceNumber, NULL, 0,
 353                         USB_CTRL_SET_TIMEOUT);
 354         if (result < 0) {
 355                 dev_err(&port->dev, "failed set request 0x%x status: %d\n",
 356                                 req, result);
 357         }
 358
 359         return result;
 360 }
 361
 362 /*
 363  * Writes a variable-sized block of CP210X_ registers, identified by req.
 364  * Data in buf must be in native USB byte order.
 365  */
 366 static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
 367                 void *buf, int bufsize)
 368 {
 369         struct usb_serial *serial = port->serial;
 370         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 371         void *dmabuf;
 372         int result;
 373
 374         dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
 375         if (!dmabuf)
 376                 return -ENOMEM;
 377
 378         result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 379                         req, REQTYPE_HOST_TO_INTERFACE, 0,
 380                         port_priv->bInterfaceNumber, dmabuf, bufsize,
 381                         USB_CTRL_SET_TIMEOUT);
 382
 383         kfree(dmabuf);
 384
 385         if (result == bufsize) {
 386                 result = 0;
 387         } else {
 388                 dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
 389                                 req, bufsize, result);
 390                 if (result >= 0)
 391                         result = -EPROTO;
 392         }
 393
 394         return result;
 395 }
 396
 397 /*
 398  * Writes any 32-bit CP210X_ register identified by req.
 399  */
 400 static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
 401 {
 402         __le32 le32_val;
 403
 404         le32_val = cpu_to_le32(val);
 405
 406         return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
 407 }
 408
 409 /*
 410  * Detect CP2108 GET_LINE_CTL bug and activate workaround.
 411  * Write a known good value 0x800, read it back.
 412  * If it comes back swapped the bug is detected.
 413  * Preserve the original register value.
 414  */
 415 static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)
 416 {
 417         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 418         u16 line_ctl_save;
 419         u16 line_ctl_test;
 420         int err;
 421
 422         err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);
 423         if (err)
 424                 return err;
 425
 426         err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);
 427         if (err)
 428                 return err;
 429
 430         err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);
 431         if (err)
 432                 return err;
 433
 434         if (line_ctl_test == 8) {
 435                 port_priv->has_swapped_line_ctl = true;
 436                 line_ctl_save = swab16(line_ctl_save);
 437         }
 438
 439         return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);
 440 }
 441
 442 /*
 443  * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)
 444  * to workaround cp2108 bug and get correct value.
 445  */
 446 static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)
 447 {
 448         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 449         int err;
 450
 451         err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);
 452         if (err)
 453                 return err;
 454
 455         /* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */
 456         if (port_priv->has_swapped_line_ctl)
 457                 *ctl = swab16(*ctl);
 458
 459         return 0;
 460 }
 461
 462 /*
 463  * cp210x_quantise_baudrate
 464  * Quantises the baud rate as per AN205 Table 1
 465  */
 466 static unsigned int cp210x_quantise_baudrate(unsigned int baud)
 467 {
 468         if (baud <= 300)
 469                 baud = 300;
 470         else if (baud <= 600)      baud = 600;
 471         else if (baud <= 1200)     baud = 1200;
 472         else if (baud <= 1800)     baud = 1800;
 473         else if (baud <= 2400)     baud = 2400;
 474         else if (baud <= 4000)     baud = 4000;
 475         else if (baud <= 4803)     baud = 4800;
 476         else if (baud <= 7207)     baud = 7200;
 477         else if (baud <= 9612)     baud = 9600;
 478         else if (baud <= 14428)    baud = 14400;
 479         else if (baud <= 16062)    baud = 16000;
 480         else if (baud <= 19250)    baud = 19200;
 481         else if (baud <= 28912)    baud = 28800;
 482         else if (baud <= 38601)    baud = 38400;
 483         else if (baud <= 51558)    baud = 51200;
 484         else if (baud <= 56280)    baud = 56000;
 485         else if (baud <= 58053)    baud = 57600;
 486         else if (baud <= 64111)    baud = 64000;
 487         else if (baud <= 77608)    baud = 76800;
 488         else if (baud <= 117028)   baud = 115200;
 489         else if (baud <= 129347)   baud = 128000;
 490         else if (baud <= 156868)   baud = 153600;
 491         else if (baud <= 237832)   baud = 230400;
 492         else if (baud <= 254234)   baud = 250000;
 493         else if (baud <= 273066)   baud = 256000;
 494         else if (baud <= 491520)   baud = 460800;
 495         else if (baud <= 567138)   baud = 500000;
 496         else if (baud <= 670254)   baud = 576000;
 497         else if (baud < 1000000)
 498                 baud = 921600;
 499         else if (baud > 2000000)
 500                 baud = 2000000;
 501         return baud;
 502 }
 503
 504 static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
 505 {
 506         int result;
 507
 508         result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);
 509         if (result) {
 510                 dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);
 511                 return result;
 512         }
 513
 514         /* Configure the termios structure */
 515         cp210x_get_termios(tty, port);
 516
 517         /* The baud rate must be initialised on cp2104 */
 518         if (tty)
 519                 cp210x_change_speed(tty, port, NULL);
 520
 521         return usb_serial_generic_open(tty, port);
 522 }
 523
 524 static void cp210x_close(struct usb_serial_port *port)
 525 {
 526         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 527
 528         usb_serial_generic_close(port);
 529
 530         /* Clear both queues; cp2108 needs this to avoid an occasional hang */
 531         cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);
 532
 533         cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);
 534
 535         if (port_priv->is_cp2102n_a01) {
 536         int result;
 537
 538                 struct usb_serial *serial = port->serial;
 539
 540         result = usb_control_msg(serial->dev,
 541                                 usb_sndctrlpipe(serial->dev, 0),
 542                                 0x09,
 543                                 0,
 544                                 0,
 545                                 port_priv->bInterfaceNumber,
 546                                 NULL,
 547                                 0,
 548                                 USB_CTRL_SET_TIMEOUT);
 549
 550
 551                 if (result < 0) {
 552                         dev_err(&port->dev, "failed usb_control_msg (1) request 0x09 status: %d\n",
 553                                         result);
 554                 }
 555
 556                 result = usb_control_msg(serial->dev,
 557                                 usb_sndctrlpipe(serial->dev, 0),
 558                                 0x09,
 559                                 0,
 560                                 1,
 561                                 port_priv->bInterfaceNumber,
 562                                 NULL,
 563                                 0,
 564                                 USB_CTRL_SET_TIMEOUT);
 565
 566
 567                 if (result < 0) {
 568                         dev_err(&port->dev, "failed usb_control_msg (2) request 0x09 status: %d\n",
 569                                         result);
 570                 }
 571
 572
 573                 result = usb_control_msg(serial->dev,
 574                                 usb_sndctrlpipe(serial->dev, 0),
 575                                 0x01,
 576                                 2,
 577                                 0,
 578                                 0x82,
 579                                 NULL,
 580                                 0,
 581                                 USB_CTRL_SET_TIMEOUT);
 582
 583
 584                 if (result < 0) {
 585                         dev_err(&port->dev, "failed usb_control_msg (1) request 0x01 status: %d\n",
 586                                         result);
 587                 }
 588
 589                 result = usb_control_msg(serial->dev,
 590                                 usb_sndctrlpipe(serial->dev, 0),
 591                                 0x01,
 592                                 2,
 593                                 0,
 594                                 0x02,
 595                                 NULL,
 596                                 0,
 597                                 USB_CTRL_SET_TIMEOUT);
 598
 599
 600                 if (result < 0) {
 601                         dev_err(&port->dev, "failed usb_control_msg (2) request 0x01 status: %d\n",
 602                                         result);
 603                 }
 604
 605         }
 606 }
 607
 608 /*
 609  * Reads a variable-sized vendor-specific register identified by wValue
 610  * Returns data into buf in native USB byte order.
 611  */
 612 static int cp210x_read_vs_reg_block(struct usb_serial_port *port, u8 bmRequestType,
 613                 u16 wValue, void *buf, int bufsize)
 614 {
 615         struct usb_serial *serial = port->serial;
 616         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 617         void *dmabuf;
 618         int result;
 619
 620         dmabuf = kmalloc(bufsize, GFP_KERNEL);
 621         if (!dmabuf)
 622                 return -ENOMEM;
 623
 624         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 625                         CP210X_VENDOR_SPECIFIC, bmRequestType, wValue,
 626                         port_priv->bInterfaceNumber, dmabuf, bufsize,
 627                         USB_CTRL_SET_TIMEOUT);
 628         if (result == bufsize) {
 629                 memcpy(buf, dmabuf, bufsize);
 630                 result = 0;
 631         } else {
 632                 dev_err(&port->dev, "failed get VENDOR_SPECIFIC wValue 0x%x size %d status: %d\n",
 633                                 wValue, bufsize, result);
 634                 if (result >= 0)
 635                         result = -EPROTO;
 636         }
 637
 638         kfree(dmabuf);
 639
 640         return result;
 641 }
 642
 643 /* GPIO register read from single-interface CP210x */
 644 static int cp210x_read_device_gpio_u8(struct usb_serial_port *port, u8 *val)
 645 {
 646         return cp210x_read_vs_reg_block(port, REQTYPE_DEVICE_TO_HOST, CP210X_READ_LATCH, val, 1);
 647 }
 648
 649 /* GPIO register read from CP2105 */
 650 static int cp210x_read_interface_gpio_u8(struct usb_serial_port *port, u8 *val)
 651 {
 652         return cp210x_read_vs_reg_block(port, REQTYPE_INTERFACE_TO_HOST, CP210X_READ_LATCH, val, 1);
 653 }
 654
 655 /* GPIO register read from CP2108 */
 656 static int cp210x_read_device_gpio_u16(struct usb_serial_port *port, u16 *val)
 657 {
 658         __le16 le16_val;
 659         int err = cp210x_read_vs_reg_block(port, REQTYPE_DEVICE_TO_HOST, CP210X_READ_LATCH, &le16_val, 2);
 660         if (err)
 661                 return err;
 662
 663         *val = le16_to_cpu(le16_val);
 664         return 0;
 665 }
 666
 667 /* GPIO register write to single-interface CP210x */
 668 static int cp210x_write_device_gpio_u16(struct usb_serial_port *port, u16 val)
 669 {
 670         int result;
 671
 672         result = usb_control_msg(port->serial->dev,
 673                         usb_sndctrlpipe(port->serial->dev, 0),
 674                         CP210X_VENDOR_SPECIFIC,
 675                         REQTYPE_HOST_TO_DEVICE,
 676                         CP210X_WRITE_LATCH, /* wValue */
 677                         val, /* wIndex */
 678                         NULL, 0, USB_CTRL_SET_TIMEOUT);
 679         if (result != 0) {
 680                 dev_err(&port->dev, "failed set WRITE_LATCH status: %d\n",
 681                                 result);
 682                 if (result >= 0)
 683                         result = -EPROTO;
 684         }
 685         return result;
 686 }
 687
 688 /*
 689  * Writes a variable-sized block of CP210X_ registers, identified by req.
 690  * Data in buf must be in native USB byte order.
 691  */
 692 static int cp210x_write_gpio_reg_block(struct usb_serial_port *port,
 693                 u8 bmRequestType, void *buf, int bufsize)
 694 {
 695         struct usb_serial *serial = port->serial;
 696         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 697         void *dmabuf;
 698         int result;
 699
 700         dmabuf = kmalloc(bufsize, GFP_KERNEL);
 701         if (!dmabuf)
 702                 return -ENOMEM;
 703
 704         memcpy(dmabuf, buf, bufsize);
 705
 706         result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 707                         CP210X_VENDOR_SPECIFIC, bmRequestType,
 708                         CP210X_WRITE_LATCH,  /* wValue */
 709                         port_priv->bInterfaceNumber, /* wIndex */
 710                         dmabuf, bufsize,
 711                         USB_CTRL_SET_TIMEOUT);
 712
 713         kfree(dmabuf);
 714
 715         if (result == bufsize) {
 716                 result = 0;
 717         } else {
 718                 dev_err(&port->dev, "failed set WRITE_LATCH size %d status: %d\n",
 719                                 bufsize, result);
 720                 if (result >= 0)
 721                         result = -EPROTO;
 722         }
 723
 724         return result;
 725 }
 726
 727 /* GPIO register write to CP2105 */
 728 static int cp210x_write_interface_gpio_u16(struct usb_serial_port *port, u16 val)
 729 {
 730         __le16 le16_val = cpu_to_le16(val);
 731
 732         return cp210x_write_gpio_reg_block(port, REQTYPE_HOST_TO_INTERFACE, &le16_val, 2);
 733 }
 734
 735 /* GPIO register write to CP2108 */
 736 static int cp210x_write_device_gpio_u32(struct usb_serial_port *port, u32 val)
 737 {
 738         __le32 le32_val = cpu_to_le32(val);
 739
 740         return cp210x_write_gpio_reg_block(port, REQTYPE_HOST_TO_DEVICE, &le32_val, 4);
 741 }
 742
 743 static int cp210x_ioctl(struct tty_struct *tty,
 744         unsigned int cmd, unsigned long arg)
 745 {
 746         struct usb_serial_port *port = tty->driver_data;
 747         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 748
 749         switch (cmd) {
 750         case IOCTL_GPIOGET:
 751                 if ((port_priv->bPartNumber == CP2103_PARTNUM) ||
 752                         (port_priv->bPartNumber == CP2104_PARTNUM) ||
 753                         (port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN28) ||
 754                         (port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN24) ||
 755                         (port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN20)) {
 756                         u8 gpio;
 757                         int err = cp210x_read_device_gpio_u8(port, &gpio);
 758                         if (err)
 759                                 return err;
 760                         if (copy_to_user((void*)arg, &gpio, sizeof(gpio)))
 761                                 return -EFAULT;
 762                         return 0;
 763                 }
 764                 else if (port_priv->bPartNumber == CP2105_PARTNUM) {
 765                         u8 gpio;
 766                         int err = cp210x_read_interface_gpio_u8(port, &gpio);
 767                         if (err)
 768                                 return err;
 769                         if (copy_to_user((void*)arg, &gpio, sizeof(gpio)))
 770                                 return -EFAULT;
 771                         return 0;
 772                 }
 773                 else if (port_priv->bPartNumber == CP2108_PARTNUM) {
 774                         u16 gpio;
 775                         int err = cp210x_read_device_gpio_u16(port, &gpio);
 776                         if (err)
 777                                 return err;
 778                         if (copy_to_user((void*)arg, &gpio, sizeof(gpio)))
 779                                 return -EFAULT;
 780                         return 0;
 781                 }
 782                 else {
 783                         return -ENOTSUPP;
 784                 }
 785                 break;
 786         case IOCTL_GPIOSET:
 787                 if ((port_priv->bPartNumber == CP2103_PARTNUM) ||
 788                         (port_priv->bPartNumber == CP2104_PARTNUM) ||
 789                         (port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN28) ||
 790                         (port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN24) ||
 791                         (port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN20)) {
 792                         u16 gpio;
 793                         if (copy_from_user(&gpio, (void*)arg, sizeof(gpio)))
 794                                 return -EFAULT;
 795                         return cp210x_write_device_gpio_u16(port, gpio);
 796                 }
 797                 else if (port_priv->bPartNumber == CP2105_PARTNUM) {
 798                         u16 gpio;
 799                         if (copy_from_user(&gpio, (void*)arg, sizeof(gpio)))
 800                                 return -EFAULT;
 801                         return cp210x_write_interface_gpio_u16(port, gpio);
 802                 }
 803                 else if (port_priv->bPartNumber == CP2108_PARTNUM) {
 804                         u32 gpio;
 805                         if (copy_from_user(&gpio, (void*)arg, sizeof(gpio)))
 806                                 return -EFAULT;
 807                         return cp210x_write_device_gpio_u32(port, gpio);
 808                 }
 809                 else {
 810                         return -ENOTSUPP;
 811                 }
 812                 break;
 813
 814         default:
 815                 break;
 816         }
 817
 818         return -ENOIOCTLCMD;
 819 }
 820
 821 /*
 822  * Read how many bytes are waiting in the TX queue.
 823  */
 824 static int cp210x_get_tx_queue_byte_count(struct usb_serial_port *port,
 825                 u32 *count)
 826 {
 827         struct usb_serial *serial = port->serial;
 828         struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
 829         struct cp210x_comm_status *sts;
 830         int result;
 831
 832         sts = kmalloc(sizeof(*sts), GFP_KERNEL);
 833         if (!sts)
 834                 return -ENOMEM;
 835
 836         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 837                         CP210X_GET_COMM_STATUS, REQTYPE_INTERFACE_TO_HOST,
 838                         0, port_priv->bInterfaceNumber, sts, sizeof(*sts),
 839                         USB_CTRL_GET_TIMEOUT);
 840         if (result == sizeof(*sts)) {
 841                 *count = le32_to_cpu(sts->ulAmountInOutQueue);
 842                 result = 0;
 843         } else {
 844                 dev_err(&port->dev, "failed to get comm status: %d\n", result);
 845                 if (result >= 0)
 846                         result = -EPROTO;
 847         }
 848
 849         kfree(sts);
 850
 851         return result;
 852 }
 853
 854 static bool cp210x_tx_empty(struct usb_serial_port *port)
 855 {
 856         int err;
 857         u32 count;
 858
 859         err = cp210x_get_tx_queue_byte_count(port, &count);
 860         if (err)
 861                 return true;
 862
 863         return !count;
 864 }
 865
 866 /*
 867  * cp210x_get_termios
 868  * Reads the baud rate, data bits, parity, stop bits and flow control mode
 869  * from the device, corrects any unsupported values, and configures the
 870  * termios structure to reflect the state of the device
 871  */
 872 static void cp210x_get_termios(struct tty_struct *tty,
 873         struct usb_serial_port *port)
 874 {
 875         unsigned int baud;
 876
 877         if (tty) {
 878                 cp210x_get_termios_port(tty->driver_data,
 879                         &tty->termios.c_cflag, &baud);
 880                 tty_encode_baud_rate(tty, baud, baud);
 881         } else {
 882                 tcflag_t cflag;
 883                 cflag = 0;
 884                 cp210x_get_termios_port(port, &cflag, &baud);
 885         }
 886 }
 887
 888 /*
 889  * cp210x_get_termios_port
 890  * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
 891  */
 892 static void cp210x_get_termios_port(struct usb_serial_port *port,
 893         tcflag_t *cflagp, unsigned int *baudp)
 894 {
 895         struct device *dev = &port->dev;
 896         tcflag_t cflag;
 897         struct cp210x_flow_ctl flow_ctl;
 898         u32 baud;
 899         u16 bits;
 900         u32 ctl_hs;
 901
 902         cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
 903
 904         dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
 905         *baudp = baud;
 906
 907         cflag = *cflagp;
 908
 909         cp210x_get_line_ctl(port, &bits);
 910         cflag &= ~CSIZE;
 911         switch (bits & BITS_DATA_MASK) {
 912         case BITS_DATA_5:
 913                 dev_dbg(dev, "%s - data bits = 5\n", __func__);
 914                 cflag |= CS5;
 915                 break;
 916         case BITS_DATA_6:
 917                 dev_dbg(dev, "%s - data bits = 6\n", __func__);
 918                 cflag |= CS6;
 919                 break;
 920         case BITS_DATA_7:
 921                 dev_dbg(dev, "%s - data bits = 7\n", __func__);
 922                 cflag |= CS7;
 923                 break;
 924         case BITS_DATA_8:
 925                 dev_dbg(dev, "%s - data bits = 8\n", __func__);
 926                 cflag |= CS8;
 927                 break;
 928         case BITS_DATA_9:
 929                 dev_dbg(dev, "%s - data bits = 9 (not supported, using 8 data bits)\n", __func__);
 930                 cflag |= CS8;
 931                 bits &= ~BITS_DATA_MASK;
 932                 bits |= BITS_DATA_8;
 933                 cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
 934                 break;
 935         default:
 936                 dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);
 937                 cflag |= CS8;
 938                 bits &= ~BITS_DATA_MASK;
 939                 bits |= BITS_DATA_8;
 940                 cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
 941                 break;
 942         }
 943
 944         switch (bits & BITS_PARITY_MASK) {
 945         case BITS_PARITY_NONE:
 946                 dev_dbg(dev, "%s - parity = NONE\n", __func__);
 947                 cflag &= ~PARENB;
 948                 break;
 949         case BITS_PARITY_ODD:
 950                 dev_dbg(dev, "%s - parity = ODD\n", __func__);
 951                 cflag |= (PARENB|PARODD);
 952                 break;
 953         case BITS_PARITY_EVEN:
 954                 dev_dbg(dev, "%s - parity = EVEN\n", __func__);
 955                 cflag &= ~PARODD;
 956                 cflag |= PARENB;
 957                 break;
 958         case BITS_PARITY_MARK:
 959                 dev_dbg(dev, "%s - parity = MARK\n", __func__);
 960                 cflag |= (PARENB|PARODD|CMSPAR);
 961                 break;
 962         case BITS_PARITY_SPACE:
 963                 dev_dbg(dev, "%s - parity = SPACE\n", __func__);
 964                 cflag &= ~PARODD;
 965                 cflag |= (PARENB|CMSPAR);
 966                 break;
 967         default:
 968                 dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);
 969                 cflag &= ~PARENB;
 970                 bits &= ~BITS_PARITY_MASK;
 971                 cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
 972                 break;
 973         }
 974
 975         cflag &= ~CSTOPB;
 976         switch (bits & BITS_STOP_MASK) {
 977         case BITS_STOP_1:
 978                 dev_dbg(dev, "%s - stop bits = 1\n", __func__);
 979                 break;
 980         case BITS_STOP_1_5:
 981                 dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);
 982                 bits &= ~BITS_STOP_MASK;
 983                 cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
 984                 break;
 985         case BITS_STOP_2:
 986                 dev_dbg(dev, "%s - stop bits = 2\n", __func__);
 987                 cflag |= CSTOPB;
 988                 break;
 989         default:
 990                 dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);
 991                 bits &= ~BITS_STOP_MASK;
 992                 cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);
 993                 break;
 994         }
 995
 996         cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
 997                         sizeof(flow_ctl));
 998         ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
 999         if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
1000                 dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1001                 cflag |= CRTSCTS;
1002         } else {
1003                 dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1004                 cflag &= ~CRTSCTS;
1005         }
1006
1007         *cflagp = cflag;
1008 }
1009
1010 /*
1011  * CP2101 supports the following baud rates:
1012  *
1013  *      300, 600, 1200, 1800, 2400, 4800, 7200, 9600, 14400, 19200, 28800,
1014  *      38400, 56000, 57600, 115200, 128000, 230400, 460800, 921600
1015  *
1016  * CP2102 and CP2103 support the following additional rates:
1017  *
1018  *      4000, 16000, 51200, 64000, 76800, 153600, 250000, 256000, 500000,
1019  *      576000
1020  *
1021  * The device will map a requested rate to a supported one, but the result
1022  * of requests for rates greater than 1053257 is undefined (see AN205).
1023  *
1024  * CP2104, CP2105 and CP2110 support most rates up to 2M, 921k and 1M baud,
1025  * respectively, with an error less than 1%. The actual rates are determined
1026  * by
1027  *
1028  *      div = round(freq / (2 x prescale x request))
1029  *      actual = freq / (2 x prescale x div)
1030  *
1031  * For CP2104 and CP2105 freq is 48Mhz and prescale is 4 for request <= 365bps
1032  * or 1 otherwise.
1033  * For CP2110 freq is 24Mhz and prescale is 4 for request <= 300bps or 1
1034  * otherwise.
1035  */
1036 static void cp210x_change_speed(struct tty_struct *tty,
1037                 struct usb_serial_port *port, struct ktermios *old_termios)
1038 {
1039         u32 baud;
1040
1041         baud = tty->termios.c_ospeed;
1042
1043         /* This maps the requested rate to a rate valid on cp2102 or cp2103,
1044          * or to an arbitrary rate in [1M,2M].
1045          *
1046          * NOTE: B0 is not implemented.
1047          */
1048         baud = cp210x_quantise_baudrate(baud);
1049
1050         dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
1051         if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
1052                 dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
1053                 if (old_termios)
1054                         baud = old_termios->c_ospeed;
1055                 else
1056                         baud = 9600;
1057         }
1058
1059         tty_encode_baud_rate(tty, baud, baud);
1060 }
1061
1062 static void cp210x_set_termios(struct tty_struct *tty,
1063                 struct usb_serial_port *port, struct ktermios *old_termios)
1064 {
1065         struct device *dev = &port->dev;
1066         unsigned int cflag, old_cflag;
1067         u16 bits;
1068
1069         cflag = tty->termios.c_cflag;
1070         old_cflag = old_termios->c_cflag;
1071
1072         if (tty->termios.c_ospeed != old_termios->c_ospeed)
1073                 cp210x_change_speed(tty, port, old_termios);
1074
1075         /* If the number of data bits is to be updated */
1076         if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
1077                 cp210x_get_line_ctl(port, &bits);
1078                 bits &= ~BITS_DATA_MASK;
1079                 switch (cflag & CSIZE) {
1080                 case CS5:
1081                         bits |= BITS_DATA_5;
1082                         dev_dbg(dev, "%s - data bits = 5\n", __func__);
1083                         break;
1084                 case CS6:
1085                         bits |= BITS_DATA_6;
1086                         dev_dbg(dev, "%s - data bits = 6\n", __func__);
1087                         break;
1088                 case CS7:
1089                         bits |= BITS_DATA_7;
1090                         dev_dbg(dev, "%s - data bits = 7\n", __func__);
1091                         break;
1092                 case CS8:
1093                         bits |= BITS_DATA_8;
1094                         dev_dbg(dev, "%s - data bits = 8\n", __func__);
1095                         break;
1096                 default:
1097                         dev_dbg(dev, "cp210x driver does not support the number of bits requested, using 8 bit mode\n");
1098                         bits |= BITS_DATA_8;
1099                         break;
1100                 }
1101                 if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1102                         dev_dbg(dev, "Number of data bits requested not supported by device\n");
1103         }
1104
1105         if ((cflag     & (PARENB|PARODD|CMSPAR)) !=
1106             (old_cflag & (PARENB|PARODD|CMSPAR))) {
1107                 cp210x_get_line_ctl(port, &bits);
1108                 bits &= ~BITS_PARITY_MASK;
1109                 if (cflag & PARENB) {
1110                         if (cflag & CMSPAR) {
1111                                 if (cflag & PARODD) {
1112                                         bits |= BITS_PARITY_MARK;
1113                                         dev_dbg(dev, "%s - parity = MARK\n", __func__);
1114                                 } else {
1115                                         bits |= BITS_PARITY_SPACE;
1116                                         dev_dbg(dev, "%s - parity = SPACE\n", __func__);
1117                                 }
1118                         } else {
1119                                 if (cflag & PARODD) {
1120                                         bits |= BITS_PARITY_ODD;
1121                                         dev_dbg(dev, "%s - parity = ODD\n", __func__);
1122                                 } else {
1123                                         bits |= BITS_PARITY_EVEN;
1124                                         dev_dbg(dev, "%s - parity = EVEN\n", __func__);
1125                                 }
1126                         }
1127                 }
1128                 if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1129                         dev_dbg(dev, "Parity mode not supported by device\n");
1130         }
1131
1132         if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
1133                 cp210x_get_line_ctl(port, &bits);
1134                 bits &= ~BITS_STOP_MASK;
1135                 if (cflag & CSTOPB) {
1136                         bits |= BITS_STOP_2;
1137                         dev_dbg(dev, "%s - stop bits = 2\n", __func__);
1138                 } else {
1139                         bits |= BITS_STOP_1;
1140                         dev_dbg(dev, "%s - stop bits = 1\n", __func__);
1141                 }
1142                 if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))
1143                         dev_dbg(dev, "Number of stop bits requested not supported by device\n");
1144         }
1145
1146         if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
1147                 struct cp210x_flow_ctl flow_ctl;
1148                 u32 ctl_hs;
1149                 u32 flow_repl;
1150
1151                 cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
1152                                 sizeof(flow_ctl));
1153                 ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
1154                 flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
1155                 dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1156                                 __func__, ctl_hs, flow_repl);
1157
1158                 ctl_hs &= ~CP210X_SERIAL_DSR_HANDSHAKE;
1159                 ctl_hs &= ~CP210X_SERIAL_DCD_HANDSHAKE;
1160                 ctl_hs &= ~CP210X_SERIAL_DSR_SENSITIVITY;
1161                 ctl_hs &= ~CP210X_SERIAL_DTR_MASK;
1162                 ctl_hs |= CP210X_SERIAL_DTR_SHIFT(CP210X_SERIAL_DTR_ACTIVE);
1163                 if (cflag & CRTSCTS) {
1164                         ctl_hs |= CP210X_SERIAL_CTS_HANDSHAKE;
1165
1166                         flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1167                         flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1168                                         CP210X_SERIAL_RTS_FLOW_CTL);
1169                         dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
1170                 } else {
1171                         ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE;
1172
1173                         flow_repl &= ~CP210X_SERIAL_RTS_MASK;
1174                         flow_repl |= CP210X_SERIAL_RTS_SHIFT(
1175                                         CP210X_SERIAL_RTS_ACTIVE);
1176                         dev_dbg(dev, "%s - flow control = NONE\n", __func__);
1177                 }
1178
1179                 dev_dbg(dev, "%s - write ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
1180                                 __func__, ctl_hs, flow_repl);
1181                 flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs);
1182                 flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
1183                 cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl,
1184                                 sizeof(flow_ctl));
1185         }
1186
1187 }
1188
1189 static int cp210x_tiocmset(struct tty_struct *tty,
1190                 unsigned int set, unsigned int clear)
1191 {
1192         struct usb_serial_port *port = tty->driver_data;
1193         return cp210x_tiocmset_port(port, set, clear);
1194 }
1195
1196 static int cp210x_tiocmset_port(struct usb_serial_port *port,
1197                 unsigned int set, unsigned int clear)
1198 {
1199         u16 control = 0;
1200
1201         if (set & TIOCM_RTS) {
1202                 control |= CONTROL_RTS;
1203                 control |= CONTROL_WRITE_RTS;
1204         }
1205         if (set & TIOCM_DTR) {
1206                 control |= CONTROL_DTR;
1207                 control |= CONTROL_WRITE_DTR;
1208         }
1209         if (clear & TIOCM_RTS) {
1210                 control &= ~CONTROL_RTS;
1211                 control |= CONTROL_WRITE_RTS;
1212         }
1213         if (clear & TIOCM_DTR) {
1214                 control &= ~CONTROL_DTR;
1215                 control |= CONTROL_WRITE_DTR;
1216         }
1217
1218         dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);
1219
1220         return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);
1221 }
1222
1223 static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
1224 {
1225         if (on)
1226                 cp210x_tiocmset_port(p, TIOCM_DTR|TIOCM_RTS, 0);
1227         else
1228                 cp210x_tiocmset_port(p, 0, TIOCM_DTR|TIOCM_RTS);
1229 }
1230
1231 static int cp210x_tiocmget(struct tty_struct *tty)
1232 {
1233         struct usb_serial_port *port = tty->driver_data;
1234         u8 control;
1235         int result;
1236
1237         result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
1238         if (result)
1239                 return result;
1240
1241         result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
1242                 |((control & CONTROL_RTS) ? TIOCM_RTS : 0)
1243                 |((control & CONTROL_CTS) ? TIOCM_CTS : 0)
1244                 |((control & CONTROL_DSR) ? TIOCM_DSR : 0)
1245                 |((control & CONTROL_RING)? TIOCM_RI  : 0)
1246                 |((control & CONTROL_DCD) ? TIOCM_CD  : 0);
1247
1248         dev_dbg(&port->dev, "%s - control = 0x%.2x\n", __func__, control);
1249
1250         return result;
1251 }
1252
1253 static void cp210x_break_ctl(struct tty_struct *tty, int break_state)
1254 {
1255         struct usb_serial_port *port = tty->driver_data;
1256         u16 state;
1257
1258         if (break_state == 0)
1259                 state = BREAK_OFF;
1260         else
1261                 state = BREAK_ON;
1262         dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1263                 state == BREAK_OFF ? "off" : "on");
1264         cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);
1265 }
1266
1267 static int cp210x_port_probe(struct usb_serial_port *port)
1268 {
1269         struct usb_serial *serial = port->serial;
1270         struct usb_host_interface *cur_altsetting;
1271         struct cp210x_port_private *port_priv;
1272         int ret;
1273
1274         port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
1275         if (!port_priv)
1276                 return -ENOMEM;
1277
1278         cur_altsetting = serial->interface->cur_altsetting;
1279         port_priv->bInterfaceNumber = cur_altsetting->desc.bInterfaceNumber;
1280         port_priv->is_cp2102n_a01 = false;
1281
1282         usb_set_serial_port_data(port, port_priv);
1283
1284         ret = cp210x_read_vs_reg_block(port, REQTYPE_DEVICE_TO_HOST,
1285                         CP210X_GET_PARTNUM, &port_priv->bPartNumber, 1);
1286         if (ret) {
1287                 kfree(port_priv);
1288                 return ret;
1289         }
1290
1291         if ((port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN28) ||
1292                 (port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN24) ||
1293                 (port_priv->bPartNumber == CP210x_PARTNUM_CP2102N_QFN20)) {
1294                         // check the firmware version on the CP2102N.
1295                         u8 fwversion[3];
1296                         ret = cp210x_read_vs_reg_block(port, REQTYPE_DEVICE_TO_HOST, CP2102N_GET_FW_VERS, fwversion, sizeof(fwversion));
1297                         if (0 == ret) {
1298                                 if (1 == fwversion[0] && 0 == fwversion[1] && fwversion[2] < 8) {
1299                                         port_priv->is_cp2102n_a01 = true;
1300                                 }
1301                         }
1302
1303                 }
1304
1305         ret = cp210x_detect_swapped_line_ctl(port);
1306         if (ret) {
1307                 kfree(port_priv);
1308                 return ret;
1309         }
1310
1311         return 0;
1312 }
1313
1314 static void cp210x_port_remove(struct usb_serial_port *port)
1315 {
1316         struct cp210x_port_private *port_priv;
1317
1318         port_priv = usb_get_serial_port_data(port);
1319         kfree(port_priv);
1320 }
1321
1322 module_usb_serial_driver(serial_drivers, id_table);
1323
1324 MODULE_DESCRIPTION(DRIVER_DESC);
1325 MODULE_LICENSE("GPL v2");