1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * mxser.c -- MOXA Smartio/Industio family multiport serial driver. 4 * 5 * Copyright (C) 1999-2006 Moxa Technologies (support@moxa.com). 6 * Copyright (C) 2006-2008 Jiri Slaby <jirislaby@gmail.com> 7 * 8 * This code is loosely based on the 1.8 moxa driver which is based on 9 * Linux serial driver, written by Linus Torvalds, Theodore T'so and 10 * others. 11 * 12 * Fed through a cleanup, indent and remove of non 2.6 code by Alan Cox 13 * <alan@lxorguk.ukuu.org.uk>. The original 1.8 code is available on 14 * www.moxa.com. 15 * - Fixed x86_64 cleanness 16 */ 17 18#include <linux/module.h> 19#include <linux/errno.h> 20#include <linux/signal.h> 21#include <linux/sched.h> 22#include <linux/timer.h> 23#include <linux/interrupt.h> 24#include <linux/tty.h> 25#include <linux/tty_flip.h> 26#include <linux/serial.h> 27#include <linux/serial_reg.h> 28#include <linux/major.h> 29#include <linux/string.h> 30#include <linux/fcntl.h> 31#include <linux/ptrace.h> 32#include <linux/ioport.h> 33#include <linux/mm.h> 34#include <linux/delay.h> 35#include <linux/pci.h> 36#include <linux/bitops.h> 37#include <linux/slab.h> 38#include <linux/ratelimit.h> 39 40#include <asm/io.h> 41#include <asm/irq.h> 42#include <linux/uaccess.h> 43 44/* 45 * Semi-public control interfaces 46 */ 47 48/* 49 * MOXA ioctls 50 */ 51 52#define MOXA 0x400 53#define MOXA_SET_OP_MODE (MOXA + 66) 54#define MOXA_GET_OP_MODE (MOXA + 67) 55 56#define RS232_MODE 0 57#define RS485_2WIRE_MODE 1 58#define RS422_MODE 2 59#define RS485_4WIRE_MODE 3 60#define OP_MODE_MASK 3 61 62/* --------------------------------------------------- */ 63 64/* 65 * Follow just what Moxa Must chip defines. 66 * 67 * When LCR register (offset 0x03) is written the following value, the Must chip 68 * will enter enhanced mode. And a write to EFR (offset 0x02) bit 6,7 will 69 * change bank. 70 */ 71#define MOXA_MUST_ENTER_ENHANCED 0xBF 72 73/* when enhanced mode is enabled, access to general bank register */ 74#define MOXA_MUST_GDL_REGISTER 0x07 75#define MOXA_MUST_GDL_MASK 0x7F 76#define MOXA_MUST_GDL_HAS_BAD_DATA 0x80 77 78#define MOXA_MUST_LSR_RERR 0x80 /* error in receive FIFO */ 79/* enhanced register bank select and enhanced mode setting register */ 80/* This works only when LCR register equals to 0xBF */ 81#define MOXA_MUST_EFR_REGISTER 0x02 82#define MOXA_MUST_EFR_EFRB_ENABLE 0x10 /* enhanced mode enable */ 83/* enhanced register bank set 0, 1, 2 */ 84#define MOXA_MUST_EFR_BANK0 0x00 85#define MOXA_MUST_EFR_BANK1 0x40 86#define MOXA_MUST_EFR_BANK2 0x80 87#define MOXA_MUST_EFR_BANK3 0xC0 88#define MOXA_MUST_EFR_BANK_MASK 0xC0 89 90/* set XON1 value register, when LCR=0xBF and change to bank0 */ 91#define MOXA_MUST_XON1_REGISTER 0x04 92 93/* set XON2 value register, when LCR=0xBF and change to bank0 */ 94#define MOXA_MUST_XON2_REGISTER 0x05 95 96/* set XOFF1 value register, when LCR=0xBF and change to bank0 */ 97#define MOXA_MUST_XOFF1_REGISTER 0x06 98 99/* set XOFF2 value register, when LCR=0xBF and change to bank0 */ 100#define MOXA_MUST_XOFF2_REGISTER 0x07 101 102#define MOXA_MUST_RBRTL_REGISTER 0x04 103#define MOXA_MUST_RBRTH_REGISTER 0x05 104#define MOXA_MUST_RBRTI_REGISTER 0x06 105#define MOXA_MUST_THRTL_REGISTER 0x07 106#define MOXA_MUST_ENUM_REGISTER 0x04 107#define MOXA_MUST_HWID_REGISTER 0x05 108#define MOXA_MUST_ECR_REGISTER 0x06 109#define MOXA_MUST_CSR_REGISTER 0x07 110 111#define MOXA_MUST_FCR_GDA_MODE_ENABLE 0x20 /* good data mode enable */ 112#define MOXA_MUST_FCR_GDA_ONLY_ENABLE 0x10 /* only good data put into RxFIFO */ 113 114#define MOXA_MUST_IER_ECTSI 0x80 /* enable CTS interrupt */ 115#define MOXA_MUST_IER_ERTSI 0x40 /* enable RTS interrupt */ 116#define MOXA_MUST_IER_XINT 0x20 /* enable Xon/Xoff interrupt */ 117#define MOXA_MUST_IER_EGDAI 0x10 /* enable GDA interrupt */ 118 119#define MOXA_MUST_RECV_ISR (UART_IER_RDI | MOXA_MUST_IER_EGDAI) 120 121/* GDA interrupt pending */ 122#define MOXA_MUST_IIR_GDA 0x1C 123#define MOXA_MUST_IIR_RDA 0x04 124#define MOXA_MUST_IIR_RTO 0x0C 125#define MOXA_MUST_IIR_LSR 0x06 126 127/* received Xon/Xoff or specical interrupt pending */ 128#define MOXA_MUST_IIR_XSC 0x10 129 130/* RTS/CTS change state interrupt pending */ 131#define MOXA_MUST_IIR_RTSCTS 0x20 132#define MOXA_MUST_IIR_MASK 0x3E 133 134#define MOXA_MUST_MCR_XON_FLAG 0x40 135#define MOXA_MUST_MCR_XON_ANY 0x80 136#define MOXA_MUST_MCR_TX_XON 0x08 137 138#define MOXA_MUST_EFR_SF_MASK 0x0F /* software flow control on chip mask value */ 139#define MOXA_MUST_EFR_SF_TX1 0x08 /* send Xon1/Xoff1 */ 140#define MOXA_MUST_EFR_SF_TX2 0x04 /* send Xon2/Xoff2 */ 141#define MOXA_MUST_EFR_SF_TX12 0x0C /* send Xon1,Xon2/Xoff1,Xoff2 */ 142#define MOXA_MUST_EFR_SF_TX_NO 0x00 /* don't send Xon/Xoff */ 143#define MOXA_MUST_EFR_SF_TX_MASK 0x0C /* Tx software flow control mask */ 144#define MOXA_MUST_EFR_SF_RX_NO 0x00 /* don't receive Xon/Xoff */ 145#define MOXA_MUST_EFR_SF_RX1 0x02 /* receive Xon1/Xoff1 */ 146#define MOXA_MUST_EFR_SF_RX2 0x01 /* receive Xon2/Xoff2 */ 147#define MOXA_MUST_EFR_SF_RX12 0x03 /* receive Xon1,Xon2/Xoff1,Xoff2 */ 148#define MOXA_MUST_EFR_SF_RX_MASK 0x03 /* Rx software flow control mask */ 149 150#define MXSERMAJOR 174 151 152#define MXSER_BOARDS 4 /* Max. boards */ 153#define MXSER_PORTS_PER_BOARD 8 /* Max. ports per board */ 154#define MXSER_PORTS (MXSER_BOARDS * MXSER_PORTS_PER_BOARD) 155#define MXSER_ISR_PASS_LIMIT 100 156 157#define WAKEUP_CHARS 256 158 159#define MXSER_BAUD_BASE 921600 160#define MXSER_CUSTOM_DIVISOR (MXSER_BAUD_BASE * 16) 161 162#define PCI_DEVICE_ID_MOXA_RC7000 0x0001 163#define PCI_DEVICE_ID_MOXA_CP102 0x1020 164#define PCI_DEVICE_ID_MOXA_CP102UL 0x1021 165#define PCI_DEVICE_ID_MOXA_CP102U 0x1022 166#define PCI_DEVICE_ID_MOXA_CP102UF 0x1023 167#define PCI_DEVICE_ID_MOXA_C104 0x1040 168#define PCI_DEVICE_ID_MOXA_CP104U 0x1041 169#define PCI_DEVICE_ID_MOXA_CP104JU 0x1042 170#define PCI_DEVICE_ID_MOXA_CP104EL 0x1043 171#define PCI_DEVICE_ID_MOXA_POS104UL 0x1044 172#define PCI_DEVICE_ID_MOXA_CB108 0x1080 173#define PCI_DEVICE_ID_MOXA_CP112UL 0x1120 174#define PCI_DEVICE_ID_MOXA_CT114 0x1140 175#define PCI_DEVICE_ID_MOXA_CP114 0x1141 176#define PCI_DEVICE_ID_MOXA_CB114 0x1142 177#define PCI_DEVICE_ID_MOXA_CP114UL 0x1143 178#define PCI_DEVICE_ID_MOXA_CP118U 0x1180 179#define PCI_DEVICE_ID_MOXA_CP118EL 0x1181 180#define PCI_DEVICE_ID_MOXA_CP132 0x1320 181#define PCI_DEVICE_ID_MOXA_CP132U 0x1321 182#define PCI_DEVICE_ID_MOXA_CP134U 0x1340 183#define PCI_DEVICE_ID_MOXA_CB134I 0x1341 184#define PCI_DEVICE_ID_MOXA_CP138U 0x1380 185#define PCI_DEVICE_ID_MOXA_C168 0x1680 186#define PCI_DEVICE_ID_MOXA_CP168U 0x1681 187#define PCI_DEVICE_ID_MOXA_CP168EL 0x1682 188 189#define MXSER_NPORTS(ddata) ((ddata) & 0xffU) 190#define MXSER_HIGHBAUD 0x0100 191 192enum mxser_must_hwid { 193 MOXA_OTHER_UART = 0x00, 194 MOXA_MUST_MU150_HWID = 0x01, 195 MOXA_MUST_MU860_HWID = 0x02, 196}; 197 198static const struct { 199 u8 type; 200 u8 fifo_size; 201 u8 rx_high_water; 202 u8 rx_low_water; 203 speed_t max_baud; 204} Gpci_uart_info[] = { 205 { MOXA_OTHER_UART, 16, 14, 1, 921600 }, 206 { MOXA_MUST_MU150_HWID, 64, 48, 16, 230400 }, 207 { MOXA_MUST_MU860_HWID, 128, 96, 32, 921600 } 208}; 209#define UART_INFO_NUM ARRAY_SIZE(Gpci_uart_info) 210 211 212/* driver_data correspond to the lines in the structure above 213 see also ISA probe function before you change something */ 214static const struct pci_device_id mxser_pcibrds[] = { 215 { PCI_DEVICE_DATA(MOXA, C168, 8) }, 216 { PCI_DEVICE_DATA(MOXA, C104, 4) }, 217 { PCI_DEVICE_DATA(MOXA, CP132, 2) }, 218 { PCI_DEVICE_DATA(MOXA, CP114, 4) }, 219 { PCI_DEVICE_DATA(MOXA, CT114, 4) }, 220 { PCI_DEVICE_DATA(MOXA, CP102, 2 | MXSER_HIGHBAUD) }, 221 { PCI_DEVICE_DATA(MOXA, CP104U, 4) }, 222 { PCI_DEVICE_DATA(MOXA, CP168U, 8) }, 223 { PCI_DEVICE_DATA(MOXA, CP132U, 2) }, 224 { PCI_DEVICE_DATA(MOXA, CP134U, 4) }, 225 { PCI_DEVICE_DATA(MOXA, CP104JU, 4) }, 226 { PCI_DEVICE_DATA(MOXA, RC7000, 8) }, /* RC7000 */ 227 { PCI_DEVICE_DATA(MOXA, CP118U, 8) }, 228 { PCI_DEVICE_DATA(MOXA, CP102UL, 2) }, 229 { PCI_DEVICE_DATA(MOXA, CP102U, 2) }, 230 { PCI_DEVICE_DATA(MOXA, CP118EL, 8) }, 231 { PCI_DEVICE_DATA(MOXA, CP168EL, 8) }, 232 { PCI_DEVICE_DATA(MOXA, CP104EL, 4) }, 233 { PCI_DEVICE_DATA(MOXA, CB108, 8) }, 234 { PCI_DEVICE_DATA(MOXA, CB114, 4) }, 235 { PCI_DEVICE_DATA(MOXA, CB134I, 4) }, 236 { PCI_DEVICE_DATA(MOXA, CP138U, 8) }, 237 { PCI_DEVICE_DATA(MOXA, POS104UL, 4) }, 238 { PCI_DEVICE_DATA(MOXA, CP114UL, 4) }, 239 { PCI_DEVICE_DATA(MOXA, CP102UF, 2) }, 240 { PCI_DEVICE_DATA(MOXA, CP112UL, 2) }, 241 { } 242}; 243MODULE_DEVICE_TABLE(pci, mxser_pcibrds); 244 245static int ttymajor = MXSERMAJOR; 246 247/* Variables for insmod */ 248 249MODULE_AUTHOR("Casper Yang"); 250MODULE_DESCRIPTION("MOXA Smartio/Industio Family Multiport Board Device Driver"); 251module_param(ttymajor, int, 0); 252MODULE_LICENSE("GPL"); 253 254struct mxser_board; 255 256struct mxser_port { 257 struct tty_port port; 258 struct mxser_board *board; 259 260 unsigned long ioaddr; 261 unsigned long opmode_ioaddr; 262 263 u8 rx_high_water; 264 u8 rx_low_water; 265 int type; /* UART type */ 266 267 u8 x_char; /* xon/xoff character */ 268 u8 IER; /* Interrupt Enable Register */ 269 u8 MCR; /* Modem control register */ 270 u8 FCR; /* FIFO control register */ 271 272 struct async_icount icount; /* kernel counters for 4 input interrupts */ 273 unsigned int timeout; 274 275 u8 read_status_mask; 276 u8 ignore_status_mask; 277 u8 xmit_fifo_size; 278 279 spinlock_t slock; 280}; 281 282struct mxser_board { 283 unsigned int idx; 284 unsigned short nports; 285 int irq; 286 unsigned long vector; 287 288 enum mxser_must_hwid must_hwid; 289 speed_t max_baud; 290 291 struct mxser_port ports[] __counted_by(nports); 292}; 293 294static DECLARE_BITMAP(mxser_boards, MXSER_BOARDS); 295static struct tty_driver *mxvar_sdriver; 296 297static u8 __mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set, 298 bool restore_LCR) 299{ 300 u8 oldlcr, efr; 301 302 oldlcr = inb(baseio + UART_LCR); 303 outb(MOXA_MUST_ENTER_ENHANCED, baseio + UART_LCR); 304 305 efr = inb(baseio + MOXA_MUST_EFR_REGISTER); 306 efr &= ~clear; 307 efr |= set; 308 309 outb(efr, baseio + MOXA_MUST_EFR_REGISTER); 310 311 if (restore_LCR) 312 outb(oldlcr, baseio + UART_LCR); 313 314 return oldlcr; 315} 316 317static u8 mxser_must_select_bank(unsigned long baseio, u8 bank) 318{ 319 return __mxser_must_set_EFR(baseio, MOXA_MUST_EFR_BANK_MASK, bank, 320 false); 321} 322 323static void mxser_set_must_xon1_value(unsigned long baseio, u8 value) 324{ 325 u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK0); 326 outb(value, baseio + MOXA_MUST_XON1_REGISTER); 327 outb(oldlcr, baseio + UART_LCR); 328} 329 330static void mxser_set_must_xoff1_value(unsigned long baseio, u8 value) 331{ 332 u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK0); 333 outb(value, baseio + MOXA_MUST_XOFF1_REGISTER); 334 outb(oldlcr, baseio + UART_LCR); 335} 336 337static void mxser_set_must_fifo_value(struct mxser_port *info) 338{ 339 u8 oldlcr = mxser_must_select_bank(info->ioaddr, MOXA_MUST_EFR_BANK1); 340 outb(info->rx_high_water, info->ioaddr + MOXA_MUST_RBRTH_REGISTER); 341 outb(info->rx_high_water, info->ioaddr + MOXA_MUST_RBRTI_REGISTER); 342 outb(info->rx_low_water, info->ioaddr + MOXA_MUST_RBRTL_REGISTER); 343 outb(oldlcr, info->ioaddr + UART_LCR); 344} 345 346static void mxser_set_must_enum_value(unsigned long baseio, u8 value) 347{ 348 u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK2); 349 outb(value, baseio + MOXA_MUST_ENUM_REGISTER); 350 outb(oldlcr, baseio + UART_LCR); 351} 352 353static u8 mxser_get_must_hardware_id(unsigned long baseio) 354{ 355 u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK2); 356 u8 id = inb(baseio + MOXA_MUST_HWID_REGISTER); 357 outb(oldlcr, baseio + UART_LCR); 358 359 return id; 360} 361 362static void mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set) 363{ 364 __mxser_must_set_EFR(baseio, clear, set, true); 365} 366 367static void mxser_must_set_enhance_mode(unsigned long baseio, bool enable) 368{ 369 mxser_must_set_EFR(baseio, 370 enable ? 0 : MOXA_MUST_EFR_EFRB_ENABLE, 371 enable ? MOXA_MUST_EFR_EFRB_ENABLE : 0); 372} 373 374static void mxser_must_no_sw_flow_control(unsigned long baseio) 375{ 376 mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_MASK, 0); 377} 378 379static void mxser_must_set_tx_sw_flow_control(unsigned long baseio, bool enable) 380{ 381 mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_TX_MASK, 382 enable ? MOXA_MUST_EFR_SF_TX1 : 0); 383} 384 385static void mxser_must_set_rx_sw_flow_control(unsigned long baseio, bool enable) 386{ 387 mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_RX_MASK, 388 enable ? MOXA_MUST_EFR_SF_RX1 : 0); 389} 390 391static enum mxser_must_hwid mxser_must_get_hwid(unsigned long io) 392{ 393 u8 oldmcr, hwid; 394 int i; 395 396 outb(0, io + UART_LCR); 397 mxser_must_set_enhance_mode(io, false); 398 oldmcr = inb(io + UART_MCR); 399 outb(0, io + UART_MCR); 400 mxser_set_must_xon1_value(io, 0x11); 401 if (inb(io + UART_MCR) != 0) { 402 outb(oldmcr, io + UART_MCR); 403 return MOXA_OTHER_UART; 404 } 405 406 hwid = mxser_get_must_hardware_id(io); 407 for (i = 1; i < UART_INFO_NUM; i++) /* 0 = OTHER_UART */ 408 if (hwid == Gpci_uart_info[i].type) 409 return hwid; 410 411 return MOXA_OTHER_UART; 412} 413 414static bool mxser_16550A_or_MUST(struct mxser_port *info) 415{ 416 return info->type == PORT_16550A || info->board->must_hwid; 417} 418 419static void mxser_process_txrx_fifo(struct mxser_port *info) 420{ 421 unsigned int i; 422 423 if (info->type == PORT_16450 || info->type == PORT_8250) { 424 info->rx_high_water = 1; 425 info->rx_low_water = 1; 426 info->xmit_fifo_size = 1; 427 return; 428 } 429 430 for (i = 0; i < UART_INFO_NUM; i++) 431 if (info->board->must_hwid == Gpci_uart_info[i].type) { 432 info->rx_low_water = Gpci_uart_info[i].rx_low_water; 433 info->rx_high_water = Gpci_uart_info[i].rx_high_water; 434 info->xmit_fifo_size = Gpci_uart_info[i].fifo_size; 435 break; 436 } 437} 438 439static void __mxser_start_tx(struct mxser_port *info) 440{ 441 outb(info->IER & ~UART_IER_THRI, info->ioaddr + UART_IER); 442 info->IER |= UART_IER_THRI; 443 outb(info->IER, info->ioaddr + UART_IER); 444} 445 446static void mxser_start_tx(struct mxser_port *info) 447{ 448 unsigned long flags; 449 450 spin_lock_irqsave(&info->slock, flags); 451 __mxser_start_tx(info); 452 spin_unlock_irqrestore(&info->slock, flags); 453} 454 455static void __mxser_stop_tx(struct mxser_port *info) 456{ 457 info->IER &= ~UART_IER_THRI; 458 outb(info->IER, info->ioaddr + UART_IER); 459} 460 461static bool mxser_carrier_raised(struct tty_port *port) 462{ 463 struct mxser_port *mp = container_of(port, struct mxser_port, port); 464 465 return inb(mp->ioaddr + UART_MSR) & UART_MSR_DCD; 466} 467 468static void mxser_dtr_rts(struct tty_port *port, bool active) 469{ 470 struct mxser_port *mp = container_of(port, struct mxser_port, port); 471 unsigned long flags; 472 u8 mcr; 473 474 spin_lock_irqsave(&mp->slock, flags); 475 mcr = inb(mp->ioaddr + UART_MCR); 476 if (active) 477 mcr |= UART_MCR_DTR | UART_MCR_RTS; 478 else 479 mcr &= ~(UART_MCR_DTR | UART_MCR_RTS); 480 outb(mcr, mp->ioaddr + UART_MCR); 481 spin_unlock_irqrestore(&mp->slock, flags); 482} 483 484static int mxser_set_baud(struct tty_struct *tty, speed_t newspd) 485{ 486 struct mxser_port *info = tty->driver_data; 487 unsigned int quot = 0, baud; 488 unsigned char cval; 489 u64 timeout; 490 491 if (newspd > info->board->max_baud) 492 return -1; 493 494 if (newspd == 134) { 495 quot = 2 * MXSER_BAUD_BASE / 269; 496 tty_encode_baud_rate(tty, 134, 134); 497 } else if (newspd) { 498 quot = MXSER_BAUD_BASE / newspd; 499 if (quot == 0) 500 quot = 1; 501 baud = MXSER_BAUD_BASE / quot; 502 tty_encode_baud_rate(tty, baud, baud); 503 } else { 504 quot = 0; 505 } 506 507 /* 508 * worst case (128 * 1000 * 10 * 18432) needs 35 bits, so divide in the 509 * u64 domain 510 */ 511 timeout = (u64)info->xmit_fifo_size * HZ * 10 * quot; 512 do_div(timeout, MXSER_BAUD_BASE); 513 info->timeout = timeout + HZ / 50; /* Add .02 seconds of slop */ 514 515 if (quot) { 516 info->MCR |= UART_MCR_DTR; 517 outb(info->MCR, info->ioaddr + UART_MCR); 518 } else { 519 info->MCR &= ~UART_MCR_DTR; 520 outb(info->MCR, info->ioaddr + UART_MCR); 521 return 0; 522 } 523 524 cval = inb(info->ioaddr + UART_LCR); 525 526 outb(cval | UART_LCR_DLAB, info->ioaddr + UART_LCR); /* set DLAB */ 527 528 outb(quot & 0xff, info->ioaddr + UART_DLL); /* LS of divisor */ 529 outb(quot >> 8, info->ioaddr + UART_DLM); /* MS of divisor */ 530 outb(cval, info->ioaddr + UART_LCR); /* reset DLAB */ 531 532 if (C_BAUD(tty) == BOTHER) { 533 quot = MXSER_BAUD_BASE % newspd; 534 quot *= 8; 535 if (quot % newspd > newspd / 2) { 536 quot /= newspd; 537 quot++; 538 } else 539 quot /= newspd; 540 541 mxser_set_must_enum_value(info->ioaddr, quot); 542 } else { 543 mxser_set_must_enum_value(info->ioaddr, 0); 544 } 545 546 return 0; 547} 548 549static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info, 550 u8 msr) 551{ 552 bool cts = msr & UART_MSR_CTS; 553 554 if (tty->hw_stopped) { 555 if (cts) { 556 tty->hw_stopped = false; 557 558 if (!mxser_16550A_or_MUST(info)) 559 __mxser_start_tx(info); 560 tty_wakeup(tty); 561 } 562 return; 563 } else if (cts) 564 return; 565 566 tty->hw_stopped = true; 567 if (!mxser_16550A_or_MUST(info)) 568 __mxser_stop_tx(info); 569} 570 571/* 572 * This routine is called to set the UART divisor registers to match 573 * the specified baud rate for a serial port. 574 */ 575static void mxser_change_speed(struct tty_struct *tty, 576 const struct ktermios *old_termios) 577{ 578 struct mxser_port *info = tty->driver_data; 579 unsigned cflag, cval; 580 581 cflag = tty->termios.c_cflag; 582 583 if (mxser_set_baud(tty, tty_get_baud_rate(tty))) { 584 /* Use previous rate on a failure */ 585 if (old_termios) { 586 speed_t baud = tty_termios_baud_rate(old_termios); 587 tty_encode_baud_rate(tty, baud, baud); 588 } 589 } 590 591 /* byte size and parity */ 592 cval = UART_LCR_WLEN(tty_get_char_size(tty->termios.c_cflag)); 593 594 if (cflag & CSTOPB) 595 cval |= UART_LCR_STOP; 596 if (cflag & PARENB) 597 cval |= UART_LCR_PARITY; 598 if (!(cflag & PARODD)) 599 cval |= UART_LCR_EPAR; 600 if (cflag & CMSPAR) 601 cval |= UART_LCR_SPAR; 602 603 info->FCR = 0; 604 if (info->board->must_hwid) { 605 info->FCR |= UART_FCR_ENABLE_FIFO | 606 MOXA_MUST_FCR_GDA_MODE_ENABLE; 607 mxser_set_must_fifo_value(info); 608 } else if (info->type != PORT_8250 && info->type != PORT_16450) { 609 info->FCR |= UART_FCR_ENABLE_FIFO; 610 switch (info->rx_high_water) { 611 case 1: 612 info->FCR |= UART_FCR_TRIGGER_1; 613 break; 614 case 4: 615 info->FCR |= UART_FCR_TRIGGER_4; 616 break; 617 case 8: 618 info->FCR |= UART_FCR_TRIGGER_8; 619 break; 620 default: 621 info->FCR |= UART_FCR_TRIGGER_14; 622 break; 623 } 624 } 625 626 /* CTS flow control flag and modem status interrupts */ 627 info->IER &= ~UART_IER_MSI; 628 info->MCR &= ~UART_MCR_AFE; 629 tty_port_set_cts_flow(&info->port, cflag & CRTSCTS); 630 if (cflag & CRTSCTS) { 631 info->IER |= UART_IER_MSI; 632 if (mxser_16550A_or_MUST(info)) { 633 info->MCR |= UART_MCR_AFE; 634 } else { 635 mxser_handle_cts(tty, info, 636 inb(info->ioaddr + UART_MSR)); 637 } 638 } 639 outb(info->MCR, info->ioaddr + UART_MCR); 640 tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL); 641 if (~cflag & CLOCAL) 642 info->IER |= UART_IER_MSI; 643 outb(info->IER, info->ioaddr + UART_IER); 644 645 /* 646 * Set up parity check flag 647 */ 648 info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; 649 if (I_INPCK(tty)) 650 info->read_status_mask |= UART_LSR_FE | UART_LSR_PE; 651 if (I_BRKINT(tty) || I_PARMRK(tty)) 652 info->read_status_mask |= UART_LSR_BI; 653 654 info->ignore_status_mask = 0; 655 656 if (I_IGNBRK(tty)) { 657 info->ignore_status_mask |= UART_LSR_BI; 658 info->read_status_mask |= UART_LSR_BI; 659 /* 660 * If we're ignore parity and break indicators, ignore 661 * overruns too. (For real raw support). 662 */ 663 if (I_IGNPAR(tty)) { 664 info->ignore_status_mask |= 665 UART_LSR_OE | 666 UART_LSR_PE | 667 UART_LSR_FE; 668 info->read_status_mask |= 669 UART_LSR_OE | 670 UART_LSR_PE | 671 UART_LSR_FE; 672 } 673 } 674 if (info->board->must_hwid) { 675 mxser_set_must_xon1_value(info->ioaddr, START_CHAR(tty)); 676 mxser_set_must_xoff1_value(info->ioaddr, STOP_CHAR(tty)); 677 mxser_must_set_rx_sw_flow_control(info->ioaddr, I_IXON(tty)); 678 mxser_must_set_tx_sw_flow_control(info->ioaddr, I_IXOFF(tty)); 679 } 680 681 682 outb(info->FCR, info->ioaddr + UART_FCR); 683 outb(cval, info->ioaddr + UART_LCR); 684} 685 686static u8 mxser_check_modem_status(struct tty_struct *tty, 687 struct mxser_port *port) 688{ 689 u8 msr = inb(port->ioaddr + UART_MSR); 690 691 if (!(msr & UART_MSR_ANY_DELTA)) 692 return msr; 693 694 /* update input line counters */ 695 if (msr & UART_MSR_TERI) 696 port->icount.rng++; 697 if (msr & UART_MSR_DDSR) 698 port->icount.dsr++; 699 if (msr & UART_MSR_DDCD) 700 port->icount.dcd++; 701 if (msr & UART_MSR_DCTS) 702 port->icount.cts++; 703 wake_up_interruptible(&port->port.delta_msr_wait); 704 705 if (tty_port_check_carrier(&port->port) && (msr & UART_MSR_DDCD)) { 706 if (msr & UART_MSR_DCD) 707 wake_up_interruptible(&port->port.open_wait); 708 } 709 710 if (tty_port_cts_enabled(&port->port)) 711 mxser_handle_cts(tty, port, msr); 712 713 return msr; 714} 715 716static void mxser_disable_and_clear_FIFO(struct mxser_port *info) 717{ 718 u8 fcr = UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT; 719 720 if (info->board->must_hwid) 721 fcr |= MOXA_MUST_FCR_GDA_MODE_ENABLE; 722 723 outb(fcr, info->ioaddr + UART_FCR); 724} 725 726static int mxser_activate(struct tty_port *port, struct tty_struct *tty) 727{ 728 struct mxser_port *info = container_of(port, struct mxser_port, port); 729 unsigned long flags; 730 int ret; 731 732 ret = tty_port_alloc_xmit_buf(port); 733 if (ret < 0) 734 return ret; 735 736 spin_lock_irqsave(&info->slock, flags); 737 738 if (!info->type) { 739 set_bit(TTY_IO_ERROR, &tty->flags); 740 spin_unlock_irqrestore(&info->slock, flags); 741 ret = 0; 742 goto err_free_xmit; 743 } 744 745 /* 746 * Clear the FIFO buffers and disable them 747 * (they will be reenabled in mxser_change_speed()) 748 */ 749 mxser_disable_and_clear_FIFO(info); 750 751 /* 752 * At this point there's no way the LSR could still be 0xFF; 753 * if it is, then bail out, because there's likely no UART 754 * here. 755 */ 756 if (inb(info->ioaddr + UART_LSR) == 0xff) { 757 spin_unlock_irqrestore(&info->slock, flags); 758 if (capable(CAP_SYS_ADMIN)) { 759 set_bit(TTY_IO_ERROR, &tty->flags); 760 return 0; 761 } 762 763 ret = -ENODEV; 764 goto err_free_xmit; 765 } 766 767 /* 768 * Clear the interrupt registers. 769 */ 770 (void) inb(info->ioaddr + UART_LSR); 771 (void) inb(info->ioaddr + UART_RX); 772 (void) inb(info->ioaddr + UART_IIR); 773 (void) inb(info->ioaddr + UART_MSR); 774 775 /* 776 * Now, initialize the UART 777 */ 778 outb(UART_LCR_WLEN8, info->ioaddr + UART_LCR); /* reset DLAB */ 779 info->MCR = UART_MCR_DTR | UART_MCR_RTS; 780 outb(info->MCR, info->ioaddr + UART_MCR); 781 782 /* 783 * Finally, enable interrupts 784 */ 785 info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI; 786 787 if (info->board->must_hwid) 788 info->IER |= MOXA_MUST_IER_EGDAI; 789 outb(info->IER, info->ioaddr + UART_IER); /* enable interrupts */ 790 791 /* 792 * And clear the interrupt registers again for luck. 793 */ 794 (void) inb(info->ioaddr + UART_LSR); 795 (void) inb(info->ioaddr + UART_RX); 796 (void) inb(info->ioaddr + UART_IIR); 797 (void) inb(info->ioaddr + UART_MSR); 798 799 clear_bit(TTY_IO_ERROR, &tty->flags); 800 kfifo_reset(&port->xmit_fifo); 801 802 /* 803 * and set the speed of the serial port 804 */ 805 mxser_change_speed(tty, NULL); 806 spin_unlock_irqrestore(&info->slock, flags); 807 808 return 0; 809err_free_xmit: 810 tty_port_free_xmit_buf(port); 811 return ret; 812} 813 814/* 815 * To stop accepting input, we disable the receive line status interrupts, and 816 * tell the interrupt driver to stop checking the data ready bit in the line 817 * status register. 818 */ 819static void mxser_stop_rx(struct mxser_port *info) 820{ 821 info->IER &= ~UART_IER_RLSI; 822 if (info->board->must_hwid) 823 info->IER &= ~MOXA_MUST_RECV_ISR; 824 825 outb(info->IER, info->ioaddr + UART_IER); 826} 827 828/* 829 * This routine will shutdown a serial port 830 */ 831static void mxser_shutdown_port(struct tty_port *port) 832{ 833 struct mxser_port *info = container_of(port, struct mxser_port, port); 834 unsigned long flags; 835 836 spin_lock_irqsave(&info->slock, flags); 837 838 mxser_stop_rx(info); 839 840 /* 841 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq 842 * here so the queue might never be waken up 843 */ 844 wake_up_interruptible(&info->port.delta_msr_wait); 845 846 info->IER = 0; 847 outb(0x00, info->ioaddr + UART_IER); 848 849 /* clear Rx/Tx FIFO's */ 850 mxser_disable_and_clear_FIFO(info); 851 852 /* read data port to reset things */ 853 (void) inb(info->ioaddr + UART_RX); 854 855 856 if (info->board->must_hwid) 857 mxser_must_no_sw_flow_control(info->ioaddr); 858 859 spin_unlock_irqrestore(&info->slock, flags); 860 861 /* make sure ISR is not running while we free the buffer */ 862 synchronize_irq(info->board->irq); 863 864 tty_port_free_xmit_buf(port); 865} 866 867/* 868 * This routine is called whenever a serial port is opened. It 869 * enables interrupts for a serial port, linking in its async structure into 870 * the IRQ chain. It also performs the serial-specific 871 * initialization for the tty structure. 872 */ 873static int mxser_open(struct tty_struct *tty, struct file *filp) 874{ 875 struct tty_port *tport = tty->port; 876 struct mxser_port *port = container_of(tport, struct mxser_port, port); 877 878 tty->driver_data = port; 879 880 return tty_port_open(tport, tty, filp); 881} 882 883static void mxser_flush_buffer(struct tty_struct *tty) 884{ 885 struct mxser_port *info = tty->driver_data; 886 unsigned long flags; 887 888 spin_lock_irqsave(&info->slock, flags); 889 kfifo_reset(&info->port.xmit_fifo); 890 891 outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT, 892 info->ioaddr + UART_FCR); 893 894 spin_unlock_irqrestore(&info->slock, flags); 895 896 tty_wakeup(tty); 897} 898 899static void mxser_close(struct tty_struct *tty, struct file *filp) 900{ 901 tty_port_close(tty->port, tty, filp); 902} 903 904static ssize_t mxser_write(struct tty_struct *tty, const u8 *buf, size_t count) 905{ 906 struct mxser_port *info = tty->driver_data; 907 unsigned long flags; 908 size_t written; 909 bool is_empty; 910 911 spin_lock_irqsave(&info->slock, flags); 912 written = kfifo_in(&info->port.xmit_fifo, buf, count); 913 is_empty = kfifo_is_empty(&info->port.xmit_fifo); 914 spin_unlock_irqrestore(&info->slock, flags); 915 916 if (!is_empty && !tty->flow.stopped) 917 if (!tty->hw_stopped || mxser_16550A_or_MUST(info)) 918 mxser_start_tx(info); 919 920 return written; 921} 922 923static int mxser_put_char(struct tty_struct *tty, u8 ch) 924{ 925 struct mxser_port *info = tty->driver_data; 926 unsigned long flags; 927 int ret; 928 929 spin_lock_irqsave(&info->slock, flags); 930 ret = kfifo_put(&info->port.xmit_fifo, ch); 931 spin_unlock_irqrestore(&info->slock, flags); 932 933 return ret; 934} 935 936 937static void mxser_flush_chars(struct tty_struct *tty) 938{ 939 struct mxser_port *info = tty->driver_data; 940 941 if (kfifo_is_empty(&info->port.xmit_fifo) || tty->flow.stopped || 942 (tty->hw_stopped && !mxser_16550A_or_MUST(info))) 943 return; 944 945 mxser_start_tx(info); 946} 947 948static unsigned int mxser_write_room(struct tty_struct *tty) 949{ 950 struct mxser_port *info = tty->driver_data; 951 952 return kfifo_avail(&info->port.xmit_fifo); 953} 954 955static unsigned int mxser_chars_in_buffer(struct tty_struct *tty) 956{ 957 struct mxser_port *info = tty->driver_data; 958 959 return kfifo_len(&info->port.xmit_fifo); 960} 961 962/* 963 * ------------------------------------------------------------ 964 * friends of mxser_ioctl() 965 * ------------------------------------------------------------ 966 */ 967static int mxser_get_serial_info(struct tty_struct *tty, 968 struct serial_struct *ss) 969{ 970 struct mxser_port *info = tty->driver_data; 971 struct tty_port *port = &info->port; 972 unsigned int closing_wait, close_delay; 973 974 mutex_lock(&port->mutex); 975 976 close_delay = jiffies_to_msecs(info->port.close_delay) / 10; 977 closing_wait = info->port.closing_wait; 978 if (closing_wait != ASYNC_CLOSING_WAIT_NONE) 979 closing_wait = jiffies_to_msecs(closing_wait) / 10; 980 981 ss->type = info->type; 982 ss->line = tty->index; 983 ss->port = info->ioaddr; 984 ss->irq = info->board->irq; 985 ss->flags = info->port.flags; 986 ss->baud_base = MXSER_BAUD_BASE; 987 ss->close_delay = close_delay; 988 ss->closing_wait = closing_wait; 989 ss->custom_divisor = MXSER_CUSTOM_DIVISOR, 990 mutex_unlock(&port->mutex); 991 return 0; 992} 993 994static int mxser_set_serial_info(struct tty_struct *tty, 995 struct serial_struct *ss) 996{ 997 struct mxser_port *info = tty->driver_data; 998 struct tty_port *port = &info->port; 999 speed_t baud; 1000 unsigned long sl_flags; 1001 unsigned int old_speed, close_delay, closing_wait; 1002 int retval = 0; 1003 1004 if (tty_io_error(tty)) 1005 return -EIO; 1006 1007 mutex_lock(&port->mutex); 1008 1009 if (ss->irq != info->board->irq || 1010 ss->port != info->ioaddr) { 1011 mutex_unlock(&port->mutex); 1012 return -EINVAL; 1013 } 1014 1015 old_speed = port->flags & ASYNC_SPD_MASK; 1016 1017 close_delay = msecs_to_jiffies(ss->close_delay * 10); 1018 closing_wait = ss->closing_wait; 1019 if (closing_wait != ASYNC_CLOSING_WAIT_NONE) 1020 closing_wait = msecs_to_jiffies(closing_wait * 10); 1021 1022 if (!capable(CAP_SYS_ADMIN)) { 1023 if ((ss->baud_base != MXSER_BAUD_BASE) || 1024 (close_delay != port->close_delay) || 1025 (closing_wait != port->closing_wait) || 1026 ((ss->flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK))) { 1027 mutex_unlock(&port->mutex); 1028 return -EPERM; 1029 } 1030 port->flags = (port->flags & ~ASYNC_USR_MASK) | 1031 (ss->flags & ASYNC_USR_MASK); 1032 } else { 1033 /* 1034 * OK, past this point, all the error checking has been done. 1035 * At this point, we start making changes..... 1036 */ 1037 port->flags = ((port->flags & ~ASYNC_FLAGS) | 1038 (ss->flags & ASYNC_FLAGS)); 1039 port->close_delay = close_delay; 1040 port->closing_wait = closing_wait; 1041 if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST && 1042 (ss->baud_base != MXSER_BAUD_BASE || 1043 ss->custom_divisor != 1044 MXSER_CUSTOM_DIVISOR)) { 1045 if (ss->custom_divisor == 0) { 1046 mutex_unlock(&port->mutex); 1047 return -EINVAL; 1048 } 1049 baud = ss->baud_base / ss->custom_divisor; 1050 tty_encode_baud_rate(tty, baud, baud); 1051 } 1052 1053 info->type = ss->type; 1054 1055 mxser_process_txrx_fifo(info); 1056 } 1057 1058 if (tty_port_initialized(port)) { 1059 if (old_speed != (port->flags & ASYNC_SPD_MASK)) { 1060 spin_lock_irqsave(&info->slock, sl_flags); 1061 mxser_change_speed(tty, NULL); 1062 spin_unlock_irqrestore(&info->slock, sl_flags); 1063 } 1064 } else { 1065 retval = mxser_activate(port, tty); 1066 if (retval == 0) 1067 tty_port_set_initialized(port, true); 1068 } 1069 mutex_unlock(&port->mutex); 1070 return retval; 1071} 1072 1073/* 1074 * mxser_get_lsr_info - get line status register info 1075 * 1076 * Purpose: Let user call ioctl() to get info when the UART physically 1077 * is emptied. On bus types like RS485, the transmitter must 1078 * release the bus after transmitting. This must be done when 1079 * the transmit shift register is empty, not be done when the 1080 * transmit holding register is empty. This functionality 1081 * allows an RS485 driver to be written in user space. 1082 */ 1083static int mxser_get_lsr_info(struct mxser_port *info, 1084 unsigned int __user *value) 1085{ 1086 unsigned char status; 1087 unsigned int result; 1088 unsigned long flags; 1089 1090 spin_lock_irqsave(&info->slock, flags); 1091 status = inb(info->ioaddr + UART_LSR); 1092 spin_unlock_irqrestore(&info->slock, flags); 1093 result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0); 1094 return put_user(result, value); 1095} 1096 1097static int mxser_tiocmget(struct tty_struct *tty) 1098{ 1099 struct mxser_port *info = tty->driver_data; 1100 unsigned char control; 1101 unsigned long flags; 1102 u8 msr; 1103 1104 if (tty_io_error(tty)) 1105 return -EIO; 1106 1107 spin_lock_irqsave(&info->slock, flags); 1108 control = info->MCR; 1109 msr = mxser_check_modem_status(tty, info); 1110 spin_unlock_irqrestore(&info->slock, flags); 1111 1112 return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0) | 1113 ((control & UART_MCR_DTR) ? TIOCM_DTR : 0) | 1114 ((msr & UART_MSR_DCD) ? TIOCM_CAR : 0) | 1115 ((msr & UART_MSR_RI) ? TIOCM_RNG : 0) | 1116 ((msr & UART_MSR_DSR) ? TIOCM_DSR : 0) | 1117 ((msr & UART_MSR_CTS) ? TIOCM_CTS : 0); 1118} 1119 1120static int mxser_tiocmset(struct tty_struct *tty, 1121 unsigned int set, unsigned int clear) 1122{ 1123 struct mxser_port *info = tty->driver_data; 1124 unsigned long flags; 1125 1126 if (tty_io_error(tty)) 1127 return -EIO; 1128 1129 spin_lock_irqsave(&info->slock, flags); 1130 1131 if (set & TIOCM_RTS) 1132 info->MCR |= UART_MCR_RTS; 1133 if (set & TIOCM_DTR) 1134 info->MCR |= UART_MCR_DTR; 1135 1136 if (clear & TIOCM_RTS) 1137 info->MCR &= ~UART_MCR_RTS; 1138 if (clear & TIOCM_DTR) 1139 info->MCR &= ~UART_MCR_DTR; 1140 1141 outb(info->MCR, info->ioaddr + UART_MCR); 1142 spin_unlock_irqrestore(&info->slock, flags); 1143 return 0; 1144} 1145 1146static int mxser_cflags_changed(struct mxser_port *info, unsigned long arg, 1147 struct async_icount *cprev) 1148{ 1149 struct async_icount cnow; 1150 unsigned long flags; 1151 int ret; 1152 1153 spin_lock_irqsave(&info->slock, flags); 1154 cnow = info->icount; /* atomic copy */ 1155 spin_unlock_irqrestore(&info->slock, flags); 1156 1157 ret = ((arg & TIOCM_RNG) && (cnow.rng != cprev->rng)) || 1158 ((arg & TIOCM_DSR) && (cnow.dsr != cprev->dsr)) || 1159 ((arg & TIOCM_CD) && (cnow.dcd != cprev->dcd)) || 1160 ((arg & TIOCM_CTS) && (cnow.cts != cprev->cts)); 1161 1162 *cprev = cnow; 1163 1164 return ret; 1165} 1166 1167/* We should likely switch to TIOCGRS485/TIOCSRS485. */ 1168static int mxser_ioctl_op_mode(struct mxser_port *port, int index, bool set, 1169 int __user *u_opmode) 1170{ 1171 int opmode, p = index % 4; 1172 int shiftbit = p * 2; 1173 u8 val; 1174 1175 if (port->board->must_hwid != MOXA_MUST_MU860_HWID) 1176 return -EFAULT; 1177 1178 if (set) { 1179 if (get_user(opmode, u_opmode)) 1180 return -EFAULT; 1181 1182 if (opmode & ~OP_MODE_MASK) 1183 return -EINVAL; 1184 1185 spin_lock_irq(&port->slock); 1186 val = inb(port->opmode_ioaddr); 1187 val &= ~(OP_MODE_MASK << shiftbit); 1188 val |= (opmode << shiftbit); 1189 outb(val, port->opmode_ioaddr); 1190 spin_unlock_irq(&port->slock); 1191 1192 return 0; 1193 } 1194 1195 spin_lock_irq(&port->slock); 1196 opmode = inb(port->opmode_ioaddr) >> shiftbit; 1197 spin_unlock_irq(&port->slock); 1198 1199 return put_user(opmode & OP_MODE_MASK, u_opmode); 1200} 1201 1202static int mxser_ioctl(struct tty_struct *tty, 1203 unsigned int cmd, unsigned long arg) 1204{ 1205 struct mxser_port *info = tty->driver_data; 1206 struct async_icount cnow; 1207 unsigned long flags; 1208 void __user *argp = (void __user *)arg; 1209 1210 if (cmd == MOXA_SET_OP_MODE || cmd == MOXA_GET_OP_MODE) 1211 return mxser_ioctl_op_mode(info, tty->index, 1212 cmd == MOXA_SET_OP_MODE, argp); 1213 1214 if (cmd != TIOCMIWAIT && tty_io_error(tty)) 1215 return -EIO; 1216 1217 switch (cmd) { 1218 case TIOCSERGETLSR: /* Get line status register */ 1219 return mxser_get_lsr_info(info, argp); 1220 /* 1221 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change 1222 * - mask passed in arg for lines of interest 1223 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking) 1224 * Caller should use TIOCGICOUNT to see which one it was 1225 */ 1226 case TIOCMIWAIT: 1227 spin_lock_irqsave(&info->slock, flags); 1228 cnow = info->icount; /* note the counters on entry */ 1229 spin_unlock_irqrestore(&info->slock, flags); 1230 1231 return wait_event_interruptible(info->port.delta_msr_wait, 1232 mxser_cflags_changed(info, arg, &cnow)); 1233 default: 1234 return -ENOIOCTLCMD; 1235 } 1236 return 0; 1237} 1238 1239 /* 1240 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS) 1241 * Return: write counters to the user passed counter struct 1242 * NB: both 1->0 and 0->1 transitions are counted except for 1243 * RI where only 0->1 is counted. 1244 */ 1245 1246static int mxser_get_icount(struct tty_struct *tty, 1247 struct serial_icounter_struct *icount) 1248 1249{ 1250 struct mxser_port *info = tty->driver_data; 1251 struct async_icount cnow; 1252 unsigned long flags; 1253 1254 spin_lock_irqsave(&info->slock, flags); 1255 cnow = info->icount; 1256 spin_unlock_irqrestore(&info->slock, flags); 1257 1258 icount->frame = cnow.frame; 1259 icount->brk = cnow.brk; 1260 icount->overrun = cnow.overrun; 1261 icount->buf_overrun = cnow.buf_overrun; 1262 icount->parity = cnow.parity; 1263 icount->rx = cnow.rx; 1264 icount->tx = cnow.tx; 1265 icount->cts = cnow.cts; 1266 icount->dsr = cnow.dsr; 1267 icount->rng = cnow.rng; 1268 icount->dcd = cnow.dcd; 1269 return 0; 1270} 1271 1272/* 1273 * This routine is called by the upper-layer tty layer to signal that 1274 * incoming characters should be throttled. 1275 */ 1276static void mxser_throttle(struct tty_struct *tty) 1277{ 1278 struct mxser_port *info = tty->driver_data; 1279 1280 if (I_IXOFF(tty)) { 1281 if (info->board->must_hwid) { 1282 info->IER &= ~MOXA_MUST_RECV_ISR; 1283 outb(info->IER, info->ioaddr + UART_IER); 1284 } else { 1285 info->x_char = STOP_CHAR(tty); 1286 outb(0, info->ioaddr + UART_IER); 1287 info->IER |= UART_IER_THRI; 1288 outb(info->IER, info->ioaddr + UART_IER); 1289 } 1290 } 1291 1292 if (C_CRTSCTS(tty)) { 1293 info->MCR &= ~UART_MCR_RTS; 1294 outb(info->MCR, info->ioaddr + UART_MCR); 1295 } 1296} 1297 1298static void mxser_unthrottle(struct tty_struct *tty) 1299{ 1300 struct mxser_port *info = tty->driver_data; 1301 1302 /* startrx */ 1303 if (I_IXOFF(tty)) { 1304 if (info->x_char) 1305 info->x_char = 0; 1306 else { 1307 if (info->board->must_hwid) { 1308 info->IER |= MOXA_MUST_RECV_ISR; 1309 outb(info->IER, info->ioaddr + UART_IER); 1310 } else { 1311 info->x_char = START_CHAR(tty); 1312 outb(0, info->ioaddr + UART_IER); 1313 info->IER |= UART_IER_THRI; 1314 outb(info->IER, info->ioaddr + UART_IER); 1315 } 1316 } 1317 } 1318 1319 if (C_CRTSCTS(tty)) { 1320 info->MCR |= UART_MCR_RTS; 1321 outb(info->MCR, info->ioaddr + UART_MCR); 1322 } 1323} 1324 1325/* 1326 * mxser_stop() and mxser_start() 1327 * 1328 * This routines are called before setting or resetting tty->flow.stopped. 1329 * They enable or disable transmitter interrupts, as necessary. 1330 */ 1331static void mxser_stop(struct tty_struct *tty) 1332{ 1333 struct mxser_port *info = tty->driver_data; 1334 unsigned long flags; 1335 1336 spin_lock_irqsave(&info->slock, flags); 1337 if (info->IER & UART_IER_THRI) 1338 __mxser_stop_tx(info); 1339 spin_unlock_irqrestore(&info->slock, flags); 1340} 1341 1342static void mxser_start(struct tty_struct *tty) 1343{ 1344 struct mxser_port *info = tty->driver_data; 1345 unsigned long flags; 1346 1347 spin_lock_irqsave(&info->slock, flags); 1348 if (!kfifo_is_empty(&info->port.xmit_fifo)) 1349 __mxser_start_tx(info); 1350 spin_unlock_irqrestore(&info->slock, flags); 1351} 1352 1353static void mxser_set_termios(struct tty_struct *tty, 1354 const struct ktermios *old_termios) 1355{ 1356 struct mxser_port *info = tty->driver_data; 1357 unsigned long flags; 1358 1359 spin_lock_irqsave(&info->slock, flags); 1360 mxser_change_speed(tty, old_termios); 1361 spin_unlock_irqrestore(&info->slock, flags); 1362 1363 if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) { 1364 tty->hw_stopped = false; 1365 mxser_start(tty); 1366 } 1367 1368 /* Handle sw stopped */ 1369 if ((old_termios->c_iflag & IXON) && !I_IXON(tty)) { 1370 tty->flow.stopped = 0; 1371 1372 if (info->board->must_hwid) { 1373 spin_lock_irqsave(&info->slock, flags); 1374 mxser_must_set_rx_sw_flow_control(info->ioaddr, false); 1375 spin_unlock_irqrestore(&info->slock, flags); 1376 } 1377 1378 mxser_start(tty); 1379 } 1380} 1381 1382static bool mxser_tx_empty(struct mxser_port *info) 1383{ 1384 unsigned long flags; 1385 u8 lsr; 1386 1387 spin_lock_irqsave(&info->slock, flags); 1388 lsr = inb(info->ioaddr + UART_LSR); 1389 spin_unlock_irqrestore(&info->slock, flags); 1390 1391 return !(lsr & UART_LSR_TEMT); 1392} 1393 1394/* 1395 * mxser_wait_until_sent() --- wait until the transmitter is empty 1396 */ 1397static void mxser_wait_until_sent(struct tty_struct *tty, int timeout) 1398{ 1399 struct mxser_port *info = tty->driver_data; 1400 unsigned long expire, char_time; 1401 1402 if (info->type == PORT_UNKNOWN) 1403 return; 1404 1405 if (info->xmit_fifo_size == 0) 1406 return; /* Just in case.... */ 1407 1408 /* 1409 * Set the check interval to be 1/5 of the estimated time to 1410 * send a single character, and make it at least 1. The check 1411 * interval should also be less than the timeout. 1412 * 1413 * Note: we have to use pretty tight timings here to satisfy 1414 * the NIST-PCTS. 1415 */ 1416 char_time = (info->timeout - HZ / 50) / info->xmit_fifo_size; 1417 char_time = char_time / 5; 1418 if (char_time == 0) 1419 char_time = 1; 1420 if (timeout && timeout < char_time) 1421 char_time = timeout; 1422 1423 char_time = jiffies_to_msecs(char_time); 1424 1425 /* 1426 * If the transmitter hasn't cleared in twice the approximate 1427 * amount of time to send the entire FIFO, it probably won't 1428 * ever clear. This assumes the UART isn't doing flow 1429 * control, which is currently the case. Hence, if it ever 1430 * takes longer than info->timeout, this is probably due to a 1431 * UART bug of some kind. So, we clamp the timeout parameter at 1432 * 2*info->timeout. 1433 */ 1434 if (!timeout || timeout > 2 * info->timeout) 1435 timeout = 2 * info->timeout; 1436 1437 expire = jiffies + timeout; 1438 1439 while (mxser_tx_empty(info)) { 1440 msleep_interruptible(char_time); 1441 if (signal_pending(current)) 1442 break; 1443 if (time_after(jiffies, expire)) 1444 break; 1445 } 1446} 1447 1448/* 1449 * This routine is called by tty_hangup() when a hangup is signaled. 1450 */ 1451static void mxser_hangup(struct tty_struct *tty) 1452{ 1453 struct mxser_port *info = tty->driver_data; 1454 1455 mxser_flush_buffer(tty); 1456 tty_port_hangup(&info->port); 1457} 1458 1459/* 1460 * mxser_rs_break() --- routine which turns the break handling on or off 1461 */ 1462static int mxser_rs_break(struct tty_struct *tty, int break_state) 1463{ 1464 struct mxser_port *info = tty->driver_data; 1465 unsigned long flags; 1466 u8 lcr; 1467 1468 spin_lock_irqsave(&info->slock, flags); 1469 lcr = inb(info->ioaddr + UART_LCR); 1470 if (break_state == -1) 1471 lcr |= UART_LCR_SBC; 1472 else 1473 lcr &= ~UART_LCR_SBC; 1474 outb(lcr, info->ioaddr + UART_LCR); 1475 spin_unlock_irqrestore(&info->slock, flags); 1476 1477 return 0; 1478} 1479 1480static bool mxser_receive_chars_new(struct mxser_port *port, u8 status) 1481{ 1482 enum mxser_must_hwid hwid = port->board->must_hwid; 1483 u8 gdl; 1484 1485 if (hwid == MOXA_OTHER_UART) 1486 return false; 1487 if (status & (UART_LSR_BRK_ERROR_BITS | MOXA_MUST_LSR_RERR)) 1488 return false; 1489 1490 gdl = inb(port->ioaddr + MOXA_MUST_GDL_REGISTER); 1491 if (hwid == MOXA_MUST_MU150_HWID) 1492 gdl &= MOXA_MUST_GDL_MASK; 1493 1494 while (gdl--) { 1495 u8 ch = inb(port->ioaddr + UART_RX); 1496 if (!tty_insert_flip_char(&port->port, ch, 0)) 1497 port->icount.buf_overrun++; 1498 } 1499 1500 return true; 1501} 1502 1503static u8 mxser_receive_chars_old(struct tty_struct *tty, 1504 struct mxser_port *port, u8 status) 1505{ 1506 enum mxser_must_hwid hwid = port->board->must_hwid; 1507 int ignored = 0; 1508 int max = 256; 1509 u8 ch; 1510 1511 do { 1512 if (max-- < 0) 1513 break; 1514 1515 ch = inb(port->ioaddr + UART_RX); 1516 if (hwid && (status & UART_LSR_OE)) 1517 outb(port->FCR | UART_FCR_CLEAR_RCVR, 1518 port->ioaddr + UART_FCR); 1519 status &= port->read_status_mask; 1520 if (status & port->ignore_status_mask) { 1521 if (++ignored > 100) 1522 break; 1523 } else { 1524 u8 flag = 0; 1525 if (status & UART_LSR_BRK_ERROR_BITS) { 1526 if (status & UART_LSR_BI) { 1527 flag = TTY_BREAK; 1528 port->icount.brk++; 1529 1530 if (port->port.flags & ASYNC_SAK) 1531 do_SAK(tty); 1532 } else if (status & UART_LSR_PE) { 1533 flag = TTY_PARITY; 1534 port->icount.parity++; 1535 } else if (status & UART_LSR_FE) { 1536 flag = TTY_FRAME; 1537 port->icount.frame++; 1538 } else if (status & UART_LSR_OE) { 1539 flag = TTY_OVERRUN; 1540 port->icount.overrun++; 1541 } 1542 } 1543 if (!tty_insert_flip_char(&port->port, ch, flag)) { 1544 port->icount.buf_overrun++; 1545 break; 1546 } 1547 } 1548 1549 if (hwid) 1550 break; 1551 1552 status = inb(port->ioaddr + UART_LSR); 1553 } while (status & UART_LSR_DR); 1554 1555 return status; 1556} 1557 1558static u8 mxser_receive_chars(struct tty_struct *tty, 1559 struct mxser_port *port, u8 status) 1560{ 1561 if (!mxser_receive_chars_new(port, status)) 1562 status = mxser_receive_chars_old(tty, port, status); 1563 1564 tty_flip_buffer_push(&port->port); 1565 1566 return status; 1567} 1568 1569static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port) 1570{ 1571 int count; 1572 1573 if (port->x_char) { 1574 outb(port->x_char, port->ioaddr + UART_TX); 1575 port->x_char = 0; 1576 port->icount.tx++; 1577 return; 1578 } 1579 1580 if (kfifo_is_empty(&port->port.xmit_fifo) || tty->flow.stopped || 1581 (tty->hw_stopped && !mxser_16550A_or_MUST(port))) { 1582 __mxser_stop_tx(port); 1583 return; 1584 } 1585 1586 count = port->xmit_fifo_size; 1587 do { 1588 u8 c; 1589 1590 if (!kfifo_get(&port->port.xmit_fifo, &c)) 1591 break; 1592 1593 outb(c, port->ioaddr + UART_TX); 1594 port->icount.tx++; 1595 } while (--count > 0); 1596 1597 if (kfifo_len(&port->port.xmit_fifo) < WAKEUP_CHARS) 1598 tty_wakeup(tty); 1599 1600 if (kfifo_is_empty(&port->port.xmit_fifo)) 1601 __mxser_stop_tx(port); 1602} 1603 1604static bool mxser_port_isr(struct mxser_port *port) 1605{ 1606 struct tty_struct *tty; 1607 u8 iir, status; 1608 bool error = false; 1609 1610 iir = inb(port->ioaddr + UART_IIR); 1611 if (iir & UART_IIR_NO_INT) 1612 return true; 1613 1614 iir &= MOXA_MUST_IIR_MASK; 1615 tty = tty_port_tty_get(&port->port); 1616 if (!tty) { 1617 status = inb(port->ioaddr + UART_LSR); 1618 outb(port->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT, 1619 port->ioaddr + UART_FCR); 1620 inb(port->ioaddr + UART_MSR); 1621 1622 error = true; 1623 goto put_tty; 1624 } 1625 1626 status = inb(port->ioaddr + UART_LSR); 1627 1628 if (port->board->must_hwid) { 1629 if (iir == MOXA_MUST_IIR_GDA || 1630 iir == MOXA_MUST_IIR_RDA || 1631 iir == MOXA_MUST_IIR_RTO || 1632 iir == MOXA_MUST_IIR_LSR) 1633 status = mxser_receive_chars(tty, port, status); 1634 } else { 1635 status &= port->read_status_mask; 1636 if (status & UART_LSR_DR) 1637 status = mxser_receive_chars(tty, port, status); 1638 } 1639 1640 mxser_check_modem_status(tty, port); 1641 1642 if (port->board->must_hwid) { 1643 if (iir == 0x02 && (status & UART_LSR_THRE)) 1644 mxser_transmit_chars(tty, port); 1645 } else { 1646 if (status & UART_LSR_THRE) 1647 mxser_transmit_chars(tty, port); 1648 } 1649 1650put_tty: 1651 tty_kref_put(tty); 1652 1653 return error; 1654} 1655 1656/* 1657 * This is the serial driver's generic interrupt routine 1658 */ 1659static irqreturn_t mxser_interrupt(int irq, void *dev_id) 1660{ 1661 struct mxser_board *brd = dev_id; 1662 struct mxser_port *port; 1663 unsigned int int_cnt, pass_counter = 0; 1664 unsigned int i, max = brd->nports; 1665 int handled = IRQ_NONE; 1666 u8 irqbits, bits, mask = BIT(max) - 1; 1667 1668 while (pass_counter++ < MXSER_ISR_PASS_LIMIT) { 1669 irqbits = inb(brd->vector) & mask; 1670 if (irqbits == mask) 1671 break; 1672 1673 handled = IRQ_HANDLED; 1674 for (i = 0, bits = 1; i < max; i++, irqbits |= bits, bits <<= 1) { 1675 if (irqbits == mask) 1676 break; 1677 if (bits & irqbits) 1678 continue; 1679 port = &brd->ports[i]; 1680 1681 int_cnt = 0; 1682 spin_lock(&port->slock); 1683 do { 1684 if (mxser_port_isr(port)) 1685 break; 1686 } while (int_cnt++ < MXSER_ISR_PASS_LIMIT); 1687 spin_unlock(&port->slock); 1688 } 1689 } 1690 1691 return handled; 1692} 1693 1694static const struct tty_operations mxser_ops = { 1695 .open = mxser_open, 1696 .close = mxser_close, 1697 .write = mxser_write, 1698 .put_char = mxser_put_char, 1699 .flush_chars = mxser_flush_chars, 1700 .write_room = mxser_write_room, 1701 .chars_in_buffer = mxser_chars_in_buffer, 1702 .flush_buffer = mxser_flush_buffer, 1703 .ioctl = mxser_ioctl, 1704 .throttle = mxser_throttle, 1705 .unthrottle = mxser_unthrottle, 1706 .set_termios = mxser_set_termios, 1707 .stop = mxser_stop, 1708 .start = mxser_start, 1709 .hangup = mxser_hangup, 1710 .break_ctl = mxser_rs_break, 1711 .wait_until_sent = mxser_wait_until_sent, 1712 .tiocmget = mxser_tiocmget, 1713 .tiocmset = mxser_tiocmset, 1714 .set_serial = mxser_set_serial_info, 1715 .get_serial = mxser_get_serial_info, 1716 .get_icount = mxser_get_icount, 1717}; 1718 1719static const struct tty_port_operations mxser_port_ops = { 1720 .carrier_raised = mxser_carrier_raised, 1721 .dtr_rts = mxser_dtr_rts, 1722 .activate = mxser_activate, 1723 .shutdown = mxser_shutdown_port, 1724}; 1725 1726/* 1727 * The MOXA Smartio/Industio serial driver boot-time initialization code! 1728 */ 1729 1730static void mxser_initbrd(struct mxser_board *brd, bool high_baud) 1731{ 1732 struct mxser_port *info; 1733 unsigned int i; 1734 bool is_mu860; 1735 1736 brd->must_hwid = mxser_must_get_hwid(brd->ports[0].ioaddr); 1737 is_mu860 = brd->must_hwid == MOXA_MUST_MU860_HWID; 1738 1739 for (i = 0; i < UART_INFO_NUM; i++) { 1740 if (Gpci_uart_info[i].type == brd->must_hwid) { 1741 brd->max_baud = Gpci_uart_info[i].max_baud; 1742 1743 /* exception....CP-102 */ 1744 if (high_baud) 1745 brd->max_baud = 921600; 1746 break; 1747 } 1748 } 1749 1750 if (is_mu860) { 1751 /* set to RS232 mode by default */ 1752 outb(0, brd->vector + 4); 1753 outb(0, brd->vector + 0x0c); 1754 } 1755 1756 for (i = 0; i < brd->nports; i++) { 1757 info = &brd->ports[i]; 1758 if (is_mu860) { 1759 if (i < 4) 1760 info->opmode_ioaddr = brd->vector + 4; 1761 else 1762 info->opmode_ioaddr = brd->vector + 0x0c; 1763 } 1764 tty_port_init(&info->port); 1765 info->port.ops = &mxser_port_ops; 1766 info->board = brd; 1767 1768 /* Enhance mode enabled here */ 1769 if (brd->must_hwid != MOXA_OTHER_UART) 1770 mxser_must_set_enhance_mode(info->ioaddr, true); 1771 1772 info->type = PORT_16550A; 1773 1774 mxser_process_txrx_fifo(info); 1775 1776 info->port.close_delay = 5 * HZ / 10; 1777 info->port.closing_wait = 30 * HZ; 1778 spin_lock_init(&info->slock); 1779 1780 /* before set INT ISR, disable all int */ 1781 outb(inb(info->ioaddr + UART_IER) & 0xf0, 1782 info->ioaddr + UART_IER); 1783 } 1784} 1785 1786static int mxser_probe(struct pci_dev *pdev, 1787 const struct pci_device_id *ent) 1788{ 1789 struct mxser_board *brd; 1790 unsigned int i, base; 1791 unsigned long ioaddress; 1792 unsigned short nports = MXSER_NPORTS(ent->driver_data); 1793 struct device *tty_dev; 1794 int retval = -EINVAL; 1795 1796 i = find_first_zero_bit(mxser_boards, MXSER_BOARDS); 1797 if (i >= MXSER_BOARDS) { 1798 dev_err(&pdev->dev, "too many boards found (maximum %d), board " 1799 "not configured\n", MXSER_BOARDS); 1800 goto err; 1801 } 1802 1803 brd = devm_kzalloc(&pdev->dev, struct_size(brd, ports, nports), 1804 GFP_KERNEL); 1805 if (!brd) 1806 goto err; 1807 1808 brd->idx = i; 1809 __set_bit(brd->idx, mxser_boards); 1810 base = i * MXSER_PORTS_PER_BOARD; 1811 1812 retval = pcim_enable_device(pdev); 1813 if (retval) { 1814 dev_err(&pdev->dev, "PCI enable failed\n"); 1815 goto err_zero; 1816 } 1817 1818 /* io address */ 1819 ioaddress = pci_resource_start(pdev, 2); 1820 retval = pci_request_region(pdev, 2, "mxser(IO)"); 1821 if (retval) 1822 goto err_zero; 1823 1824 brd->nports = nports; 1825 for (i = 0; i < nports; i++) 1826 brd->ports[i].ioaddr = ioaddress + 8 * i; 1827 1828 /* vector */ 1829 ioaddress = pci_resource_start(pdev, 3); 1830 retval = pci_request_region(pdev, 3, "mxser(vector)"); 1831 if (retval) 1832 goto err_zero; 1833 brd->vector = ioaddress; 1834 1835 /* irq */ 1836 brd->irq = pdev->irq; 1837 1838 mxser_initbrd(brd, ent->driver_data & MXSER_HIGHBAUD); 1839 1840 retval = devm_request_irq(&pdev->dev, brd->irq, mxser_interrupt, 1841 IRQF_SHARED, "mxser", brd); 1842 if (retval) { 1843 dev_err(&pdev->dev, "request irq failed"); 1844 goto err_relbrd; 1845 } 1846 1847 for (i = 0; i < nports; i++) { 1848 tty_dev = tty_port_register_device(&brd->ports[i].port, 1849 mxvar_sdriver, base + i, &pdev->dev); 1850 if (IS_ERR(tty_dev)) { 1851 retval = PTR_ERR(tty_dev); 1852 for (; i > 0; i--) 1853 tty_unregister_device(mxvar_sdriver, 1854 base + i - 1); 1855 goto err_relbrd; 1856 } 1857 } 1858 1859 pci_set_drvdata(pdev, brd); 1860 1861 return 0; 1862err_relbrd: 1863 for (i = 0; i < nports; i++) 1864 tty_port_destroy(&brd->ports[i].port); 1865err_zero: 1866 __clear_bit(brd->idx, mxser_boards); 1867err: 1868 return retval; 1869} 1870 1871static void mxser_remove(struct pci_dev *pdev) 1872{ 1873 struct mxser_board *brd = pci_get_drvdata(pdev); 1874 unsigned int i, base = brd->idx * MXSER_PORTS_PER_BOARD; 1875 1876 for (i = 0; i < brd->nports; i++) { 1877 tty_unregister_device(mxvar_sdriver, base + i); 1878 tty_port_destroy(&brd->ports[i].port); 1879 } 1880 1881 __clear_bit(brd->idx, mxser_boards); 1882} 1883 1884static struct pci_driver mxser_driver = { 1885 .name = "mxser", 1886 .id_table = mxser_pcibrds, 1887 .probe = mxser_probe, 1888 .remove = mxser_remove 1889}; 1890 1891static int __init mxser_module_init(void) 1892{ 1893 int retval; 1894 1895 mxvar_sdriver = tty_alloc_driver(MXSER_PORTS, TTY_DRIVER_REAL_RAW | 1896 TTY_DRIVER_DYNAMIC_DEV); 1897 if (IS_ERR(mxvar_sdriver)) 1898 return PTR_ERR(mxvar_sdriver); 1899 1900 /* Initialize the tty_driver structure */ 1901 mxvar_sdriver->name = "ttyMI"; 1902 mxvar_sdriver->major = ttymajor; 1903 mxvar_sdriver->minor_start = 0; 1904 mxvar_sdriver->type = TTY_DRIVER_TYPE_SERIAL; 1905 mxvar_sdriver->subtype = SERIAL_TYPE_NORMAL; 1906 mxvar_sdriver->init_termios = tty_std_termios; 1907 mxvar_sdriver->init_termios.c_cflag = B9600|CS8|CREAD|HUPCL|CLOCAL; 1908 tty_set_operations(mxvar_sdriver, &mxser_ops); 1909 1910 retval = tty_register_driver(mxvar_sdriver); 1911 if (retval) { 1912 printk(KERN_ERR "Couldn't install MOXA Smartio/Industio family " 1913 "tty driver !\n"); 1914 goto err_put; 1915 } 1916 1917 retval = pci_register_driver(&mxser_driver); 1918 if (retval) { 1919 printk(KERN_ERR "mxser: can't register pci driver\n"); 1920 goto err_unr; 1921 } 1922 1923 return 0; 1924err_unr: 1925 tty_unregister_driver(mxvar_sdriver); 1926err_put: 1927 tty_driver_kref_put(mxvar_sdriver); 1928 return retval; 1929} 1930 1931static void __exit mxser_module_exit(void) 1932{ 1933 pci_unregister_driver(&mxser_driver); 1934 tty_unregister_driver(mxvar_sdriver); 1935 tty_driver_kref_put(mxvar_sdriver); 1936} 1937 1938module_init(mxser_module_init); 1939module_exit(mxser_module_exit); 1940