1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * driver for the GE IP-OCTAL boards 4 * 5 * Copyright (C) 2009-2012 CERN (www.cern.ch) 6 * Author: Nicolas Serafini, EIC2 SA 7 * Author: Samuel Iglesias Gonsalvez <siglesias@igalia.com> 8 */ 9 10 #include <linux/device.h> 11 #include <linux/module.h> 12 #include <linux/interrupt.h> 13 #include <linux/kref.h> 14 #include <linux/rwsem.h> 15 #include <linux/sched.h> 16 #include <linux/tty.h> 17 #include <linux/serial.h> 18 #include <linux/tty_flip.h> 19 #include <linux/slab.h> 20 #include <linux/io.h> 21 #include <linux/ipack.h> 22 #include "ipoctal.h" 23 #include "scc2698.h" 24 25 #define IP_OCTAL_ID_SPACE_VECTOR 0x41 26 #define IP_OCTAL_NB_BLOCKS 4 27 28 static const struct tty_operations ipoctal_fops; 29 30 static void ipoctal_release(struct kref *kref); 31 32 struct ipoctal_channel { 33 struct ipoctal_stats stats; 34 unsigned int nb_bytes; 35 wait_queue_head_t queue; 36 spinlock_t lock; 37 unsigned int pointer_read; 38 unsigned int pointer_write; 39 struct tty_port tty_port; 40 bool tty_registered; 41 union scc2698_channel __iomem *regs; 42 union scc2698_block __iomem *block_regs; 43 unsigned int board_id; 44 u8 isr_rx_rdy_mask; 45 u8 isr_tx_rdy_mask; 46 unsigned int rx_enable; 47 }; 48 49 struct ipoctal { 50 struct ipack_device *dev; 51 unsigned int board_id; 52 struct ipoctal_channel channel[NR_CHANNELS]; 53 struct tty_driver *tty_drv; 54 u8 __iomem *mem8_space; 55 u8 __iomem *int_space; 56 struct kref kref; 57 struct module *carrier_owner; 58 struct rw_semaphore remove_sem; 59 bool removed; 60 }; 61 62 static inline struct ipoctal *chan_to_ipoctal(struct ipoctal_channel *chan, 63 unsigned int index) 64 { 65 return container_of(chan, struct ipoctal, channel[index]); 66 } 67 68 static void ipoctal_reset_channel(struct ipoctal_channel *channel) 69 { 70 iowrite8(CR_DISABLE_RX | CR_DISABLE_TX, &channel->regs->w.cr); 71 channel->rx_enable = 0; 72 iowrite8(CR_CMD_RESET_RX, &channel->regs->w.cr); 73 iowrite8(CR_CMD_RESET_TX, &channel->regs->w.cr); 74 iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr); 75 iowrite8(CR_CMD_RESET_MR, &channel->regs->w.cr); 76 } 77 78 static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty) 79 { 80 struct ipoctal_channel *channel; 81 struct ipoctal *ipoctal; 82 83 channel = dev_get_drvdata(tty->dev); 84 ipoctal = chan_to_ipoctal(channel, tty->index); 85 86 guard(rwsem_read)(&ipoctal->remove_sem); 87 if (ipoctal->removed) 88 return -ENODEV; 89 90 /* 91 * Enable RX. TX will be enabled when 92 * there is something to send 93 */ 94 iowrite8(CR_ENABLE_RX, &channel->regs->w.cr); 95 channel->rx_enable = 1; 96 return 0; 97 } 98 99 static int ipoctal_install(struct tty_driver *driver, struct tty_struct *tty) 100 { 101 struct ipoctal_channel *channel = dev_get_drvdata(tty->dev); 102 struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index); 103 int res; 104 105 if (!ipack_get_carrier(ipoctal->dev)) 106 return -EBUSY; 107 108 res = tty_standard_install(driver, tty); 109 if (res) 110 goto err_put_carrier; 111 112 kref_get(&ipoctal->kref); 113 tty->driver_data = channel; 114 115 return 0; 116 117 err_put_carrier: 118 ipack_put_carrier(ipoctal->dev); 119 120 return res; 121 } 122 123 static int ipoctal_open(struct tty_struct *tty, struct file *file) 124 { 125 struct ipoctal_channel *channel = tty->driver_data; 126 127 return tty_port_open(&channel->tty_port, tty, file); 128 } 129 130 static void ipoctal_reset_stats(struct ipoctal_stats *stats) 131 { 132 stats->tx = 0; 133 stats->rx = 0; 134 stats->rcv_break = 0; 135 stats->framing_err = 0; 136 stats->overrun_err = 0; 137 stats->parity_err = 0; 138 } 139 140 static void ipoctal_free_channel(struct ipoctal_channel *channel) 141 { 142 ipoctal_reset_stats(&channel->stats); 143 channel->pointer_read = 0; 144 channel->pointer_write = 0; 145 channel->nb_bytes = 0; 146 } 147 148 static void ipoctal_close(struct tty_struct *tty, struct file *filp) 149 { 150 struct ipoctal_channel *channel = tty->driver_data; 151 152 tty_port_close(&channel->tty_port, tty, filp); 153 ipoctal_free_channel(channel); 154 } 155 156 static int ipoctal_get_icount(struct tty_struct *tty, 157 struct serial_icounter_struct *icount) 158 { 159 struct ipoctal_channel *channel = tty->driver_data; 160 161 icount->cts = 0; 162 icount->dsr = 0; 163 icount->rng = 0; 164 icount->dcd = 0; 165 icount->rx = channel->stats.rx; 166 icount->tx = channel->stats.tx; 167 icount->frame = channel->stats.framing_err; 168 icount->parity = channel->stats.parity_err; 169 icount->brk = channel->stats.rcv_break; 170 return 0; 171 } 172 173 static void ipoctal_irq_rx(struct ipoctal_channel *channel, u8 sr) 174 { 175 struct tty_port *port = &channel->tty_port; 176 u8 isr, value, flag; 177 178 do { 179 value = ioread8(&channel->regs->r.rhr); 180 flag = TTY_NORMAL; 181 /* Error: count statistics */ 182 if (sr & SR_ERROR) { 183 iowrite8(CR_CMD_RESET_ERR_STATUS, &channel->regs->w.cr); 184 185 if (sr & SR_OVERRUN_ERROR) { 186 channel->stats.overrun_err++; 187 /* Overrun doesn't affect the current character*/ 188 tty_insert_flip_char(port, 0, TTY_OVERRUN); 189 } 190 if (sr & SR_PARITY_ERROR) { 191 channel->stats.parity_err++; 192 flag = TTY_PARITY; 193 } 194 if (sr & SR_FRAMING_ERROR) { 195 channel->stats.framing_err++; 196 flag = TTY_FRAME; 197 } 198 if (sr & SR_RECEIVED_BREAK) { 199 channel->stats.rcv_break++; 200 flag = TTY_BREAK; 201 } 202 } 203 tty_insert_flip_char(port, value, flag); 204 205 /* Check if there are more characters in RX FIFO 206 * If there are more, the isr register for this channel 207 * has enabled the RxRDY|FFULL bit. 208 */ 209 isr = ioread8(&channel->block_regs->r.isr); 210 sr = ioread8(&channel->regs->r.sr); 211 } while (isr & channel->isr_rx_rdy_mask); 212 213 tty_flip_buffer_push(port); 214 } 215 216 static void ipoctal_irq_tx(struct ipoctal_channel *channel) 217 { 218 unsigned int *pointer_write = &channel->pointer_write; 219 u8 value; 220 221 if (channel->nb_bytes == 0) 222 return; 223 224 spin_lock(&channel->lock); 225 value = channel->tty_port.xmit_buf[*pointer_write]; 226 iowrite8(value, &channel->regs->w.thr); 227 channel->stats.tx++; 228 (*pointer_write)++; 229 *pointer_write = *pointer_write % PAGE_SIZE; 230 channel->nb_bytes--; 231 spin_unlock(&channel->lock); 232 } 233 234 static void ipoctal_irq_channel(struct ipoctal_channel *channel) 235 { 236 u8 isr, sr; 237 238 /* The HW is organized in pair of channels. See which register we need 239 * to read from */ 240 isr = ioread8(&channel->block_regs->r.isr); 241 sr = ioread8(&channel->regs->r.sr); 242 243 if (isr & (IMR_DELTA_BREAK_A | IMR_DELTA_BREAK_B)) 244 iowrite8(CR_CMD_RESET_BREAK_CHANGE, &channel->regs->w.cr); 245 246 if ((sr & SR_TX_EMPTY) && (channel->nb_bytes == 0)) { 247 iowrite8(CR_DISABLE_TX, &channel->regs->w.cr); 248 /* In case of RS-485, change from TX to RX when finishing TX. 249 * Half-duplex. */ 250 if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) { 251 iowrite8(CR_CMD_NEGATE_RTSN, &channel->regs->w.cr); 252 iowrite8(CR_ENABLE_RX, &channel->regs->w.cr); 253 channel->rx_enable = 1; 254 } 255 } 256 257 /* RX data */ 258 if ((isr & channel->isr_rx_rdy_mask) && (sr & SR_RX_READY)) 259 ipoctal_irq_rx(channel, sr); 260 261 /* TX of each character */ 262 if ((isr & channel->isr_tx_rdy_mask) && (sr & SR_TX_READY)) 263 ipoctal_irq_tx(channel); 264 } 265 266 static irqreturn_t ipoctal_irq_handler(void *arg) 267 { 268 unsigned int i; 269 struct ipoctal *ipoctal = arg; 270 271 /* Clear the IPack device interrupt */ 272 readw(ipoctal->int_space + ACK_INT_REQ0); 273 readw(ipoctal->int_space + ACK_INT_REQ1); 274 275 /* Check all channels */ 276 for (i = 0; i < NR_CHANNELS; i++) 277 ipoctal_irq_channel(&ipoctal->channel[i]); 278 279 return IRQ_HANDLED; 280 } 281 282 static const struct tty_port_operations ipoctal_tty_port_ops = { 283 .dtr_rts = NULL, 284 .activate = ipoctal_port_activate, 285 }; 286 287 static int ipoctal_inst_slot(struct ipoctal *ipoctal, unsigned int bus_nr, 288 unsigned int slot) 289 { 290 int res; 291 int i; 292 struct tty_driver *drv; 293 struct ipoctal_channel *channel; 294 struct ipack_region *region; 295 void __iomem *addr; 296 union scc2698_channel __iomem *chan_regs; 297 union scc2698_block __iomem *block_regs; 298 299 ipoctal->board_id = ipoctal->dev->id_device; 300 301 region = &ipoctal->dev->region[IPACK_IO_SPACE]; 302 addr = devm_ioremap(&ipoctal->dev->dev, 303 region->start, region->size); 304 if (!addr) { 305 dev_err(&ipoctal->dev->dev, 306 "Unable to map slot [%d:%d] IO space!\n", 307 bus_nr, slot); 308 return -EADDRNOTAVAIL; 309 } 310 /* Save the virtual address to access the registers easily */ 311 chan_regs = 312 (union scc2698_channel __iomem *) addr; 313 block_regs = 314 (union scc2698_block __iomem *) addr; 315 316 region = &ipoctal->dev->region[IPACK_INT_SPACE]; 317 ipoctal->int_space = 318 devm_ioremap(&ipoctal->dev->dev, 319 region->start, region->size); 320 if (!ipoctal->int_space) { 321 dev_err(&ipoctal->dev->dev, 322 "Unable to map slot [%d:%d] INT space!\n", 323 bus_nr, slot); 324 return -EADDRNOTAVAIL; 325 } 326 327 region = &ipoctal->dev->region[IPACK_MEM8_SPACE]; 328 ipoctal->mem8_space = 329 devm_ioremap(&ipoctal->dev->dev, 330 region->start, 0x8000); 331 if (!ipoctal->mem8_space) { 332 dev_err(&ipoctal->dev->dev, 333 "Unable to map slot [%d:%d] MEM8 space!\n", 334 bus_nr, slot); 335 return -EADDRNOTAVAIL; 336 } 337 338 339 /* Disable RX and TX before touching anything */ 340 for (i = 0; i < NR_CHANNELS ; i++) { 341 struct ipoctal_channel *channel = &ipoctal->channel[i]; 342 channel->regs = chan_regs + i; 343 channel->block_regs = block_regs + (i >> 1); 344 channel->board_id = ipoctal->board_id; 345 if (i & 1) { 346 channel->isr_tx_rdy_mask = ISR_TxRDY_B; 347 channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_B; 348 } else { 349 channel->isr_tx_rdy_mask = ISR_TxRDY_A; 350 channel->isr_rx_rdy_mask = ISR_RxRDY_FFULL_A; 351 } 352 353 ipoctal_reset_channel(channel); 354 iowrite8(MR1_CHRL_8_BITS | MR1_ERROR_CHAR | MR1_RxINT_RxRDY, 355 &channel->regs->w.mr); /* mr1 */ 356 iowrite8(0, &channel->regs->w.mr); /* mr2 */ 357 iowrite8(TX_CLK_9600 | RX_CLK_9600, &channel->regs->w.csr); 358 } 359 360 for (i = 0; i < IP_OCTAL_NB_BLOCKS; i++) { 361 iowrite8(ACR_BRG_SET2, &block_regs[i].w.acr); 362 iowrite8(OPCR_MPP_OUTPUT | OPCR_MPOa_RTSN | OPCR_MPOb_RTSN, 363 &block_regs[i].w.opcr); 364 iowrite8(IMR_TxRDY_A | IMR_RxRDY_FFULL_A | IMR_DELTA_BREAK_A | 365 IMR_TxRDY_B | IMR_RxRDY_FFULL_B | IMR_DELTA_BREAK_B, 366 &block_regs[i].w.imr); 367 } 368 369 /* Dummy write */ 370 iowrite8(1, ipoctal->mem8_space + 1); 371 372 /* Register the TTY device */ 373 374 /* Each IP-OCTAL channel is a TTY port */ 375 drv = tty_alloc_driver(NR_CHANNELS, TTY_DRIVER_REAL_RAW | 376 TTY_DRIVER_DYNAMIC_DEV); 377 if (IS_ERR(drv)) 378 return PTR_ERR(drv); 379 380 /* Fill struct tty_driver with ipoctal data */ 381 drv->owner = THIS_MODULE; 382 drv->driver_name = KBUILD_MODNAME; 383 drv->name = kasprintf(GFP_KERNEL, KBUILD_MODNAME ".%d.%d.", bus_nr, slot); 384 if (!drv->name) { 385 res = -ENOMEM; 386 goto err_put_driver; 387 } 388 drv->major = 0; 389 390 drv->minor_start = 0; 391 drv->type = TTY_DRIVER_TYPE_SERIAL; 392 drv->subtype = SERIAL_TYPE_NORMAL; 393 drv->init_termios = tty_std_termios; 394 drv->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; 395 drv->init_termios.c_ispeed = 9600; 396 drv->init_termios.c_ospeed = 9600; 397 398 tty_set_operations(drv, &ipoctal_fops); 399 res = tty_register_driver(drv); 400 if (res) { 401 dev_err(&ipoctal->dev->dev, "Can't register tty driver.\n"); 402 goto err_free_name; 403 } 404 405 /* Save struct tty_driver for use it when uninstalling the device */ 406 ipoctal->tty_drv = drv; 407 408 for (i = 0; i < NR_CHANNELS; i++) { 409 struct device *tty_dev; 410 411 channel = &ipoctal->channel[i]; 412 tty_port_init(&channel->tty_port); 413 res = tty_port_alloc_xmit_buf(&channel->tty_port); 414 if (res) 415 continue; 416 channel->tty_port.ops = &ipoctal_tty_port_ops; 417 418 ipoctal_reset_stats(&channel->stats); 419 channel->nb_bytes = 0; 420 spin_lock_init(&channel->lock); 421 channel->pointer_read = 0; 422 channel->pointer_write = 0; 423 tty_dev = tty_port_register_device_attr(&channel->tty_port, drv, 424 i, NULL, channel, NULL); 425 if (IS_ERR(tty_dev)) { 426 dev_err(&ipoctal->dev->dev, "Failed to register tty device.\n"); 427 tty_port_free_xmit_buf(&channel->tty_port); 428 tty_port_destroy(&channel->tty_port); 429 continue; 430 } 431 channel->tty_registered = true; 432 } 433 434 /* 435 * IP-OCTAL has different addresses to copy its IRQ vector. 436 * Depending of the carrier these addresses are accesible or not. 437 * More info in the datasheet. 438 */ 439 ipoctal->dev->bus->ops->request_irq(ipoctal->dev, 440 ipoctal_irq_handler, ipoctal); 441 442 return 0; 443 444 err_free_name: 445 kfree(drv->name); 446 err_put_driver: 447 tty_driver_kref_put(drv); 448 449 return res; 450 } 451 452 static inline size_t ipoctal_copy_write_buffer(struct ipoctal_channel *channel, 453 const u8 *buf, size_t count) 454 { 455 unsigned long flags; 456 size_t i; 457 unsigned int *pointer_read = &channel->pointer_read; 458 459 /* Copy the bytes from the user buffer to the internal one */ 460 for (i = 0; i < count; i++) { 461 if (i <= (PAGE_SIZE - channel->nb_bytes)) { 462 spin_lock_irqsave(&channel->lock, flags); 463 channel->tty_port.xmit_buf[*pointer_read] = buf[i]; 464 *pointer_read = (*pointer_read + 1) % PAGE_SIZE; 465 channel->nb_bytes++; 466 spin_unlock_irqrestore(&channel->lock, flags); 467 } else { 468 break; 469 } 470 } 471 return i; 472 } 473 474 static ssize_t ipoctal_write_tty(struct tty_struct *tty, const u8 *buf, 475 size_t count) 476 { 477 struct ipoctal_channel *channel = tty->driver_data; 478 struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index); 479 size_t char_copied; 480 481 guard(rwsem_read)(&ipoctal->remove_sem); 482 if (ipoctal->removed || !channel->tty_port.xmit_buf) 483 return 0; 484 485 char_copied = ipoctal_copy_write_buffer(channel, buf, count); 486 487 /* As the IP-OCTAL 485 only supports half duplex, do it manually */ 488 if (channel->board_id == IPACK1_DEVICE_ID_SBS_OCTAL_485) { 489 iowrite8(CR_DISABLE_RX, &channel->regs->w.cr); 490 channel->rx_enable = 0; 491 iowrite8(CR_CMD_ASSERT_RTSN, &channel->regs->w.cr); 492 } 493 494 /* 495 * Send a packet and then disable TX to avoid failure after several send 496 * operations 497 */ 498 iowrite8(CR_ENABLE_TX, &channel->regs->w.cr); 499 return char_copied; 500 } 501 502 static unsigned int ipoctal_write_room(struct tty_struct *tty) 503 { 504 struct ipoctal_channel *channel = tty->driver_data; 505 506 return PAGE_SIZE - channel->nb_bytes; 507 } 508 509 static unsigned int ipoctal_chars_in_buffer(struct tty_struct *tty) 510 { 511 struct ipoctal_channel *channel = tty->driver_data; 512 513 return channel->nb_bytes; 514 } 515 516 static void ipoctal_set_termios(struct tty_struct *tty, 517 const struct ktermios *old_termios) 518 { 519 unsigned int cflag; 520 unsigned char mr1 = 0; 521 unsigned char mr2 = 0; 522 unsigned char csr = 0; 523 struct ipoctal_channel *channel = tty->driver_data; 524 struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index); 525 speed_t baud; 526 527 guard(rwsem_read)(&ipoctal->remove_sem); 528 if (ipoctal->removed) 529 return; 530 531 cflag = tty->termios.c_cflag; 532 533 /* Disable and reset everything before change the setup */ 534 ipoctal_reset_channel(channel); 535 536 /* Set Bits per chars */ 537 switch (cflag & CSIZE) { 538 case CS6: 539 mr1 |= MR1_CHRL_6_BITS; 540 break; 541 case CS7: 542 mr1 |= MR1_CHRL_7_BITS; 543 break; 544 case CS8: 545 default: 546 mr1 |= MR1_CHRL_8_BITS; 547 /* By default, select CS8 */ 548 tty->termios.c_cflag = (cflag & ~CSIZE) | CS8; 549 break; 550 } 551 552 /* Set Parity */ 553 if (cflag & PARENB) 554 if (cflag & PARODD) 555 mr1 |= MR1_PARITY_ON | MR1_PARITY_ODD; 556 else 557 mr1 |= MR1_PARITY_ON | MR1_PARITY_EVEN; 558 else 559 mr1 |= MR1_PARITY_OFF; 560 561 /* Mark or space parity is not supported */ 562 tty->termios.c_cflag &= ~CMSPAR; 563 564 /* Set stop bits */ 565 if (cflag & CSTOPB) 566 mr2 |= MR2_STOP_BITS_LENGTH_2; 567 else 568 mr2 |= MR2_STOP_BITS_LENGTH_1; 569 570 /* Set the flow control */ 571 switch (channel->board_id) { 572 case IPACK1_DEVICE_ID_SBS_OCTAL_232: 573 if (cflag & CRTSCTS) { 574 mr1 |= MR1_RxRTS_CONTROL_ON; 575 mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_ON; 576 } else { 577 mr1 |= MR1_RxRTS_CONTROL_OFF; 578 mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF; 579 } 580 break; 581 case IPACK1_DEVICE_ID_SBS_OCTAL_422: 582 mr1 |= MR1_RxRTS_CONTROL_OFF; 583 mr2 |= MR2_TxRTS_CONTROL_OFF | MR2_CTS_ENABLE_TX_OFF; 584 break; 585 case IPACK1_DEVICE_ID_SBS_OCTAL_485: 586 mr1 |= MR1_RxRTS_CONTROL_OFF; 587 mr2 |= MR2_TxRTS_CONTROL_ON | MR2_CTS_ENABLE_TX_OFF; 588 break; 589 default: 590 return; 591 } 592 593 baud = tty_get_baud_rate(tty); 594 tty_termios_encode_baud_rate(&tty->termios, baud, baud); 595 596 /* Set baud rate */ 597 switch (baud) { 598 case 75: 599 csr |= TX_CLK_75 | RX_CLK_75; 600 break; 601 case 110: 602 csr |= TX_CLK_110 | RX_CLK_110; 603 break; 604 case 150: 605 csr |= TX_CLK_150 | RX_CLK_150; 606 break; 607 case 300: 608 csr |= TX_CLK_300 | RX_CLK_300; 609 break; 610 case 600: 611 csr |= TX_CLK_600 | RX_CLK_600; 612 break; 613 case 1200: 614 csr |= TX_CLK_1200 | RX_CLK_1200; 615 break; 616 case 1800: 617 csr |= TX_CLK_1800 | RX_CLK_1800; 618 break; 619 case 2000: 620 csr |= TX_CLK_2000 | RX_CLK_2000; 621 break; 622 case 2400: 623 csr |= TX_CLK_2400 | RX_CLK_2400; 624 break; 625 case 4800: 626 csr |= TX_CLK_4800 | RX_CLK_4800; 627 break; 628 case 9600: 629 csr |= TX_CLK_9600 | RX_CLK_9600; 630 break; 631 case 19200: 632 csr |= TX_CLK_19200 | RX_CLK_19200; 633 break; 634 case 38400: 635 default: 636 csr |= TX_CLK_38400 | RX_CLK_38400; 637 /* In case of default, we establish 38400 bps */ 638 tty_termios_encode_baud_rate(&tty->termios, 38400, 38400); 639 break; 640 } 641 642 mr1 |= MR1_ERROR_CHAR; 643 mr1 |= MR1_RxINT_RxRDY; 644 645 /* Write the control registers */ 646 iowrite8(mr1, &channel->regs->w.mr); 647 iowrite8(mr2, &channel->regs->w.mr); 648 iowrite8(csr, &channel->regs->w.csr); 649 650 /* Enable again the RX, if it was before */ 651 if (channel->rx_enable) 652 iowrite8(CR_ENABLE_RX, &channel->regs->w.cr); 653 } 654 655 static void ipoctal_hangup(struct tty_struct *tty) 656 { 657 unsigned long flags; 658 struct ipoctal_channel *channel = tty->driver_data; 659 struct ipoctal *ipoctal; 660 661 if (channel == NULL) 662 return; 663 664 ipoctal = chan_to_ipoctal(channel, tty->index); 665 guard(rwsem_read)(&ipoctal->remove_sem); 666 if (ipoctal->removed) 667 return; 668 669 spin_lock_irqsave(&channel->lock, flags); 670 channel->nb_bytes = 0; 671 channel->pointer_read = 0; 672 channel->pointer_write = 0; 673 spin_unlock_irqrestore(&channel->lock, flags); 674 675 tty_port_hangup(&channel->tty_port); 676 677 ipoctal_reset_channel(channel); 678 tty_port_set_initialized(&channel->tty_port, false); 679 wake_up_interruptible(&channel->tty_port.open_wait); 680 } 681 682 static void ipoctal_shutdown(struct tty_struct *tty) 683 { 684 struct ipoctal_channel *channel = tty->driver_data; 685 struct ipoctal *ipoctal; 686 687 if (channel == NULL) 688 return; 689 690 ipoctal = chan_to_ipoctal(channel, tty->index); 691 guard(rwsem_read)(&ipoctal->remove_sem); 692 if (ipoctal->removed) 693 return; 694 695 ipoctal_reset_channel(channel); 696 tty_port_set_initialized(&channel->tty_port, false); 697 } 698 699 static void ipoctal_cleanup(struct tty_struct *tty) 700 { 701 struct ipoctal_channel *channel = tty->driver_data; 702 struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index); 703 704 /* release the carrier driver via cached owner */ 705 module_put(ipoctal->carrier_owner); 706 kref_put(&ipoctal->kref, ipoctal_release); 707 } 708 709 static const struct tty_operations ipoctal_fops = { 710 .ioctl = NULL, 711 .install = ipoctal_install, 712 .open = ipoctal_open, 713 .close = ipoctal_close, 714 .write = ipoctal_write_tty, 715 .set_termios = ipoctal_set_termios, 716 .write_room = ipoctal_write_room, 717 .chars_in_buffer = ipoctal_chars_in_buffer, 718 .get_icount = ipoctal_get_icount, 719 .hangup = ipoctal_hangup, 720 .shutdown = ipoctal_shutdown, 721 .cleanup = ipoctal_cleanup, 722 }; 723 724 static void ipoctal_release(struct kref *kref) 725 { 726 struct ipoctal *ipoctal = container_of(kref, struct ipoctal, kref); 727 728 kfree(ipoctal); 729 } 730 731 static int ipoctal_probe(struct ipack_device *dev) 732 { 733 int res; 734 struct ipoctal *ipoctal; 735 736 ipoctal = kzalloc_obj(struct ipoctal); 737 if (ipoctal == NULL) 738 return -ENOMEM; 739 740 kref_init(&ipoctal->kref); 741 init_rwsem(&ipoctal->remove_sem); 742 743 ipoctal->dev = dev; 744 ipoctal->carrier_owner = dev->bus->owner; 745 res = ipoctal_inst_slot(ipoctal, dev->bus->bus_nr, dev->slot); 746 if (res) 747 goto out_uninst; 748 749 dev_set_drvdata(&dev->dev, ipoctal); 750 return 0; 751 752 out_uninst: 753 kref_put(&ipoctal->kref, ipoctal_release); 754 return res; 755 } 756 757 static void __ipoctal_remove(struct ipoctal *ipoctal) 758 { 759 int i; 760 761 scoped_guard(rwsem_write, &ipoctal->remove_sem) 762 ipoctal->removed = true; 763 764 ipoctal->dev->bus->ops->free_irq(ipoctal->dev); 765 766 for (i = 0; i < NR_CHANNELS; i++) { 767 struct ipoctal_channel *channel = &ipoctal->channel[i]; 768 769 if (!channel->tty_registered) 770 continue; 771 772 tty_unregister_device(ipoctal->tty_drv, i); 773 tty_port_free_xmit_buf(&channel->tty_port); 774 tty_port_destroy(&channel->tty_port); 775 } 776 777 tty_unregister_driver(ipoctal->tty_drv); 778 kfree(ipoctal->tty_drv->name); 779 tty_driver_kref_put(ipoctal->tty_drv); 780 kref_put(&ipoctal->kref, ipoctal_release); 781 } 782 783 static void ipoctal_remove(struct ipack_device *idev) 784 { 785 __ipoctal_remove(dev_get_drvdata(&idev->dev)); 786 } 787 788 static DEFINE_IPACK_DEVICE_TABLE(ipoctal_ids) = { 789 { IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS, 790 IPACK1_DEVICE_ID_SBS_OCTAL_232) }, 791 { IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS, 792 IPACK1_DEVICE_ID_SBS_OCTAL_422) }, 793 { IPACK_DEVICE(IPACK_ID_VERSION_1, IPACK1_VENDOR_ID_SBS, 794 IPACK1_DEVICE_ID_SBS_OCTAL_485) }, 795 { 0, }, 796 }; 797 798 MODULE_DEVICE_TABLE(ipack, ipoctal_ids); 799 800 static const struct ipack_driver_ops ipoctal_drv_ops = { 801 .probe = ipoctal_probe, 802 .remove = ipoctal_remove, 803 }; 804 805 static struct ipack_driver driver = { 806 .ops = &ipoctal_drv_ops, 807 .id_table = ipoctal_ids, 808 }; 809 810 static int __init ipoctal_init(void) 811 { 812 return ipack_driver_register(&driver, THIS_MODULE, KBUILD_MODNAME); 813 } 814 815 static void __exit ipoctal_exit(void) 816 { 817 ipack_driver_unregister(&driver); 818 } 819 820 MODULE_DESCRIPTION("IP-Octal 232, 422 and 485 device driver"); 821 MODULE_LICENSE("GPL"); 822 823 module_init(ipoctal_init); 824 module_exit(ipoctal_exit); 825