1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. 4 * 5 * Copyright (C) 2004 Infineon IFAP DC COM CPE 6 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org> 7 * Copyright (C) 2007 John Crispin <john@phrozen.org> 8 * Copyright (C) 2010 Thomas Langer, <thomas.langer@lantiq.com> 9 */ 10 11 #include <linux/bitfield.h> 12 #include <linux/clk.h> 13 #include <linux/console.h> 14 #include <linux/device.h> 15 #include <linux/init.h> 16 #include <linux/io.h> 17 #include <linux/ioport.h> 18 #include <linux/lantiq.h> 19 #include <linux/module.h> 20 #include <linux/of.h> 21 #include <linux/platform_device.h> 22 #include <linux/serial.h> 23 #include <linux/serial_core.h> 24 #include <linux/slab.h> 25 #include <linux/sysrq.h> 26 #include <linux/tty.h> 27 #include <linux/tty_flip.h> 28 29 #define PORT_LTQ_ASC 111 30 #define MAXPORTS 2 31 #define UART_DUMMY_UER_RX 1 32 #define DRVNAME "lantiq,asc" 33 #ifdef __BIG_ENDIAN 34 #define LTQ_ASC_TBUF (0x0020 + 3) 35 #define LTQ_ASC_RBUF (0x0024 + 3) 36 #else 37 #define LTQ_ASC_TBUF 0x0020 38 #define LTQ_ASC_RBUF 0x0024 39 #endif 40 #define LTQ_ASC_FSTAT 0x0048 41 #define LTQ_ASC_WHBSTATE 0x0018 42 #define LTQ_ASC_STATE 0x0014 43 #define LTQ_ASC_IRNCR 0x00F8 44 #define LTQ_ASC_CLC 0x0000 45 #define LTQ_ASC_ID 0x0008 46 #define LTQ_ASC_PISEL 0x0004 47 #define LTQ_ASC_TXFCON 0x0044 48 #define LTQ_ASC_RXFCON 0x0040 49 #define LTQ_ASC_CON 0x0010 50 #define LTQ_ASC_BG 0x0050 51 #define LTQ_ASC_IRNREN 0x00F4 52 53 #define ASC_IRNREN_TX 0x1 54 #define ASC_IRNREN_RX 0x2 55 #define ASC_IRNREN_ERR 0x4 56 #define ASC_IRNREN_TX_BUF 0x8 57 #define ASC_IRNCR_TIR 0x1 58 #define ASC_IRNCR_RIR 0x2 59 #define ASC_IRNCR_EIR 0x4 60 #define ASC_IRNCR_MASK GENMASK(2, 0) 61 62 #define ASCOPT_CSIZE 0x3 63 #define TXFIFO_FL 1 64 #define RXFIFO_FL 1 65 #define ASCCLC_DISS 0x2 66 #define ASCCLC_RMCMASK 0x0000FF00 67 #define ASCCLC_RMCOFFSET 8 68 #define ASCCON_M_8ASYNC 0x0 69 #define ASCCON_M_7ASYNC 0x2 70 #define ASCCON_ODD 0x00000020 71 #define ASCCON_STP 0x00000080 72 #define ASCCON_BRS 0x00000100 73 #define ASCCON_FDE 0x00000200 74 #define ASCCON_R 0x00008000 75 #define ASCCON_FEN 0x00020000 76 #define ASCCON_ROEN 0x00080000 77 #define ASCCON_TOEN 0x00100000 78 #define ASCSTATE_PE 0x00010000 79 #define ASCSTATE_FE 0x00020000 80 #define ASCSTATE_ROE 0x00080000 81 #define ASCSTATE_ANY (ASCSTATE_ROE|ASCSTATE_PE|ASCSTATE_FE) 82 #define ASCWHBSTATE_CLRREN 0x00000001 83 #define ASCWHBSTATE_SETREN 0x00000002 84 #define ASCWHBSTATE_CLRPE 0x00000004 85 #define ASCWHBSTATE_CLRFE 0x00000008 86 #define ASCWHBSTATE_CLRROE 0x00000020 87 #define ASCTXFCON_TXFEN 0x0001 88 #define ASCTXFCON_TXFFLU 0x0002 89 #define ASCTXFCON_TXFITLMASK 0x3F00 90 #define ASCTXFCON_TXFITLOFF 8 91 #define ASCRXFCON_RXFEN 0x0001 92 #define ASCRXFCON_RXFFLU 0x0002 93 #define ASCRXFCON_RXFITLMASK 0x3F00 94 #define ASCRXFCON_RXFITLOFF 8 95 #define ASCFSTAT_RXFFLMASK 0x003F 96 #define ASCFSTAT_TXFFLMASK 0x3F00 97 #define ASCFSTAT_TXFREEMASK 0x3F000000 98 99 static struct ltq_uart_port *lqasc_port[MAXPORTS]; 100 static struct uart_driver lqasc_reg; 101 102 struct ltq_soc_data { 103 int (*fetch_irq)(struct device *dev, struct ltq_uart_port *ltq_port); 104 int (*request_irq)(struct uart_port *port); 105 void (*free_irq)(struct uart_port *port); 106 }; 107 108 struct ltq_uart_port { 109 struct uart_port port; 110 /* clock used to derive divider */ 111 struct clk *freqclk; 112 /* clock gating of the ASC core */ 113 struct clk *clk; 114 unsigned int tx_irq; 115 unsigned int rx_irq; 116 unsigned int err_irq; 117 unsigned int common_irq; 118 spinlock_t lock; /* exclusive access for multi core */ 119 120 const struct ltq_soc_data *soc; 121 }; 122 123 static inline void asc_update_bits(u32 clear, u32 set, void __iomem *reg) 124 { 125 u32 tmp = __raw_readl(reg); 126 127 __raw_writel((tmp & ~clear) | set, reg); 128 } 129 130 static inline struct 131 ltq_uart_port *to_ltq_uart_port(struct uart_port *port) 132 { 133 return container_of(port, struct ltq_uart_port, port); 134 } 135 136 static void 137 lqasc_stop_tx(struct uart_port *port) 138 { 139 return; 140 } 141 142 static bool lqasc_tx_ready(struct uart_port *port) 143 { 144 u32 fstat = __raw_readl(port->membase + LTQ_ASC_FSTAT); 145 146 return FIELD_GET(ASCFSTAT_TXFREEMASK, fstat); 147 } 148 149 static void 150 lqasc_start_tx(struct uart_port *port) 151 { 152 unsigned long flags; 153 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 154 u8 ch; 155 156 spin_lock_irqsave(<q_port->lock, flags); 157 uart_port_tx(port, ch, 158 lqasc_tx_ready(port), 159 writeb(ch, port->membase + LTQ_ASC_TBUF)); 160 spin_unlock_irqrestore(<q_port->lock, flags); 161 return; 162 } 163 164 static void 165 lqasc_stop_rx(struct uart_port *port) 166 { 167 __raw_writel(ASCWHBSTATE_CLRREN, port->membase + LTQ_ASC_WHBSTATE); 168 } 169 170 static int 171 lqasc_rx_chars(struct uart_port *port) 172 { 173 struct tty_port *tport = &port->state->port; 174 unsigned int ch = 0, rsr = 0, fifocnt; 175 176 fifocnt = __raw_readl(port->membase + LTQ_ASC_FSTAT) & 177 ASCFSTAT_RXFFLMASK; 178 while (fifocnt--) { 179 u8 flag = TTY_NORMAL; 180 ch = readb(port->membase + LTQ_ASC_RBUF); 181 rsr = (__raw_readl(port->membase + LTQ_ASC_STATE) 182 & ASCSTATE_ANY) | UART_DUMMY_UER_RX; 183 tty_flip_buffer_push(tport); 184 port->icount.rx++; 185 186 /* 187 * Note that the error handling code is 188 * out of the main execution path 189 */ 190 if (rsr & ASCSTATE_ANY) { 191 if (rsr & ASCSTATE_PE) { 192 port->icount.parity++; 193 asc_update_bits(0, ASCWHBSTATE_CLRPE, 194 port->membase + LTQ_ASC_WHBSTATE); 195 } else if (rsr & ASCSTATE_FE) { 196 port->icount.frame++; 197 asc_update_bits(0, ASCWHBSTATE_CLRFE, 198 port->membase + LTQ_ASC_WHBSTATE); 199 } 200 if (rsr & ASCSTATE_ROE) { 201 port->icount.overrun++; 202 asc_update_bits(0, ASCWHBSTATE_CLRROE, 203 port->membase + LTQ_ASC_WHBSTATE); 204 } 205 206 rsr &= port->read_status_mask; 207 208 if (rsr & ASCSTATE_PE) 209 flag = TTY_PARITY; 210 else if (rsr & ASCSTATE_FE) 211 flag = TTY_FRAME; 212 } 213 214 if ((rsr & port->ignore_status_mask) == 0) 215 tty_insert_flip_char(tport, ch, flag); 216 217 if (rsr & ASCSTATE_ROE) 218 /* 219 * Overrun is special, since it's reported 220 * immediately, and doesn't affect the current 221 * character 222 */ 223 tty_insert_flip_char(tport, 0, TTY_OVERRUN); 224 } 225 226 if (ch != 0) 227 tty_flip_buffer_push(tport); 228 229 return 0; 230 } 231 232 static irqreturn_t 233 lqasc_tx_int(int irq, void *_port) 234 { 235 unsigned long flags; 236 struct uart_port *port = (struct uart_port *)_port; 237 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 238 239 spin_lock_irqsave(<q_port->lock, flags); 240 __raw_writel(ASC_IRNCR_TIR, port->membase + LTQ_ASC_IRNCR); 241 spin_unlock_irqrestore(<q_port->lock, flags); 242 lqasc_start_tx(port); 243 return IRQ_HANDLED; 244 } 245 246 static irqreturn_t 247 lqasc_err_int(int irq, void *_port) 248 { 249 unsigned long flags; 250 struct uart_port *port = (struct uart_port *)_port; 251 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 252 253 spin_lock_irqsave(<q_port->lock, flags); 254 __raw_writel(ASC_IRNCR_EIR, port->membase + LTQ_ASC_IRNCR); 255 /* clear any pending interrupts */ 256 asc_update_bits(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE | 257 ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE); 258 spin_unlock_irqrestore(<q_port->lock, flags); 259 return IRQ_HANDLED; 260 } 261 262 static irqreturn_t 263 lqasc_rx_int(int irq, void *_port) 264 { 265 unsigned long flags; 266 struct uart_port *port = (struct uart_port *)_port; 267 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 268 269 spin_lock_irqsave(<q_port->lock, flags); 270 __raw_writel(ASC_IRNCR_RIR, port->membase + LTQ_ASC_IRNCR); 271 lqasc_rx_chars(port); 272 spin_unlock_irqrestore(<q_port->lock, flags); 273 return IRQ_HANDLED; 274 } 275 276 static irqreturn_t lqasc_irq(int irq, void *p) 277 { 278 unsigned long flags; 279 u32 stat; 280 struct uart_port *port = p; 281 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 282 283 spin_lock_irqsave(<q_port->lock, flags); 284 stat = readl(port->membase + LTQ_ASC_IRNCR); 285 spin_unlock_irqrestore(<q_port->lock, flags); 286 if (!(stat & ASC_IRNCR_MASK)) 287 return IRQ_NONE; 288 289 if (stat & ASC_IRNCR_TIR) 290 lqasc_tx_int(irq, p); 291 292 if (stat & ASC_IRNCR_RIR) 293 lqasc_rx_int(irq, p); 294 295 if (stat & ASC_IRNCR_EIR) 296 lqasc_err_int(irq, p); 297 298 return IRQ_HANDLED; 299 } 300 301 static unsigned int 302 lqasc_tx_empty(struct uart_port *port) 303 { 304 int status; 305 status = __raw_readl(port->membase + LTQ_ASC_FSTAT) & 306 ASCFSTAT_TXFFLMASK; 307 return status ? 0 : TIOCSER_TEMT; 308 } 309 310 static unsigned int 311 lqasc_get_mctrl(struct uart_port *port) 312 { 313 return TIOCM_CTS | TIOCM_CAR | TIOCM_DSR; 314 } 315 316 static void 317 lqasc_set_mctrl(struct uart_port *port, u_int mctrl) 318 { 319 } 320 321 static void 322 lqasc_break_ctl(struct uart_port *port, int break_state) 323 { 324 } 325 326 static int 327 lqasc_startup(struct uart_port *port) 328 { 329 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 330 int retval; 331 unsigned long flags; 332 333 if (!IS_ERR(ltq_port->clk)) 334 clk_prepare_enable(ltq_port->clk); 335 port->uartclk = clk_get_rate(ltq_port->freqclk); 336 337 spin_lock_irqsave(<q_port->lock, flags); 338 asc_update_bits(ASCCLC_DISS | ASCCLC_RMCMASK, (1 << ASCCLC_RMCOFFSET), 339 port->membase + LTQ_ASC_CLC); 340 341 __raw_writel(0, port->membase + LTQ_ASC_PISEL); 342 __raw_writel( 343 ((TXFIFO_FL << ASCTXFCON_TXFITLOFF) & ASCTXFCON_TXFITLMASK) | 344 ASCTXFCON_TXFEN | ASCTXFCON_TXFFLU, 345 port->membase + LTQ_ASC_TXFCON); 346 __raw_writel( 347 ((RXFIFO_FL << ASCRXFCON_RXFITLOFF) & ASCRXFCON_RXFITLMASK) 348 | ASCRXFCON_RXFEN | ASCRXFCON_RXFFLU, 349 port->membase + LTQ_ASC_RXFCON); 350 /* make sure other settings are written to hardware before 351 * setting enable bits 352 */ 353 wmb(); 354 asc_update_bits(0, ASCCON_M_8ASYNC | ASCCON_FEN | ASCCON_TOEN | 355 ASCCON_ROEN, port->membase + LTQ_ASC_CON); 356 357 spin_unlock_irqrestore(<q_port->lock, flags); 358 359 retval = ltq_port->soc->request_irq(port); 360 if (retval) 361 return retval; 362 363 __raw_writel(ASC_IRNREN_RX | ASC_IRNREN_ERR | ASC_IRNREN_TX, 364 port->membase + LTQ_ASC_IRNREN); 365 return retval; 366 } 367 368 static void 369 lqasc_shutdown(struct uart_port *port) 370 { 371 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 372 unsigned long flags; 373 374 ltq_port->soc->free_irq(port); 375 376 spin_lock_irqsave(<q_port->lock, flags); 377 __raw_writel(0, port->membase + LTQ_ASC_CON); 378 asc_update_bits(ASCRXFCON_RXFEN, ASCRXFCON_RXFFLU, 379 port->membase + LTQ_ASC_RXFCON); 380 asc_update_bits(ASCTXFCON_TXFEN, ASCTXFCON_TXFFLU, 381 port->membase + LTQ_ASC_TXFCON); 382 spin_unlock_irqrestore(<q_port->lock, flags); 383 if (!IS_ERR(ltq_port->clk)) 384 clk_disable_unprepare(ltq_port->clk); 385 } 386 387 static void 388 lqasc_set_termios(struct uart_port *port, struct ktermios *new, 389 const struct ktermios *old) 390 { 391 unsigned int cflag; 392 unsigned int iflag; 393 unsigned int divisor; 394 unsigned int baud; 395 unsigned int con = 0; 396 unsigned long flags; 397 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 398 399 cflag = new->c_cflag; 400 iflag = new->c_iflag; 401 402 switch (cflag & CSIZE) { 403 case CS7: 404 con = ASCCON_M_7ASYNC; 405 break; 406 407 case CS5: 408 case CS6: 409 default: 410 new->c_cflag &= ~ CSIZE; 411 new->c_cflag |= CS8; 412 con = ASCCON_M_8ASYNC; 413 break; 414 } 415 416 cflag &= ~CMSPAR; /* Mark/Space parity is not supported */ 417 418 if (cflag & CSTOPB) 419 con |= ASCCON_STP; 420 421 if (cflag & PARENB) { 422 if (!(cflag & PARODD)) 423 con &= ~ASCCON_ODD; 424 else 425 con |= ASCCON_ODD; 426 } 427 428 port->read_status_mask = ASCSTATE_ROE; 429 if (iflag & INPCK) 430 port->read_status_mask |= ASCSTATE_FE | ASCSTATE_PE; 431 432 port->ignore_status_mask = 0; 433 if (iflag & IGNPAR) 434 port->ignore_status_mask |= ASCSTATE_FE | ASCSTATE_PE; 435 436 if (iflag & IGNBRK) { 437 /* 438 * If we're ignoring parity and break indicators, 439 * ignore overruns too (for real raw support). 440 */ 441 if (iflag & IGNPAR) 442 port->ignore_status_mask |= ASCSTATE_ROE; 443 } 444 445 if ((cflag & CREAD) == 0) 446 port->ignore_status_mask |= UART_DUMMY_UER_RX; 447 448 /* set error signals - framing, parity and overrun, enable receiver */ 449 con |= ASCCON_FEN | ASCCON_TOEN | ASCCON_ROEN; 450 451 spin_lock_irqsave(<q_port->lock, flags); 452 453 /* set up CON */ 454 asc_update_bits(0, con, port->membase + LTQ_ASC_CON); 455 456 /* Set baud rate - take a divider of 2 into account */ 457 baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16); 458 divisor = uart_get_divisor(port, baud); 459 divisor = divisor / 2 - 1; 460 461 /* disable the baudrate generator */ 462 asc_update_bits(ASCCON_R, 0, port->membase + LTQ_ASC_CON); 463 464 /* make sure the fractional divider is off */ 465 asc_update_bits(ASCCON_FDE, 0, port->membase + LTQ_ASC_CON); 466 467 /* set up to use divisor of 2 */ 468 asc_update_bits(ASCCON_BRS, 0, port->membase + LTQ_ASC_CON); 469 470 /* now we can write the new baudrate into the register */ 471 __raw_writel(divisor, port->membase + LTQ_ASC_BG); 472 473 /* turn the baudrate generator back on */ 474 asc_update_bits(0, ASCCON_R, port->membase + LTQ_ASC_CON); 475 476 /* enable rx */ 477 __raw_writel(ASCWHBSTATE_SETREN, port->membase + LTQ_ASC_WHBSTATE); 478 479 spin_unlock_irqrestore(<q_port->lock, flags); 480 481 /* Don't rewrite B0 */ 482 if (tty_termios_baud_rate(new)) 483 tty_termios_encode_baud_rate(new, baud, baud); 484 485 uart_update_timeout(port, cflag, baud); 486 } 487 488 static const char* 489 lqasc_type(struct uart_port *port) 490 { 491 if (port->type == PORT_LTQ_ASC) 492 return DRVNAME; 493 else 494 return NULL; 495 } 496 497 static void 498 lqasc_release_port(struct uart_port *port) 499 { 500 struct platform_device *pdev = to_platform_device(port->dev); 501 502 if (port->flags & UPF_IOREMAP) { 503 devm_iounmap(&pdev->dev, port->membase); 504 port->membase = NULL; 505 } 506 } 507 508 static int 509 lqasc_request_port(struct uart_port *port) 510 { 511 struct platform_device *pdev = to_platform_device(port->dev); 512 struct resource *res; 513 int size; 514 515 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 516 if (!res) { 517 dev_err(&pdev->dev, "cannot obtain I/O memory region"); 518 return -ENODEV; 519 } 520 size = resource_size(res); 521 522 res = devm_request_mem_region(&pdev->dev, res->start, 523 size, dev_name(&pdev->dev)); 524 if (!res) { 525 dev_err(&pdev->dev, "cannot request I/O memory region"); 526 return -EBUSY; 527 } 528 529 if (port->flags & UPF_IOREMAP) { 530 port->membase = devm_ioremap(&pdev->dev, 531 port->mapbase, size); 532 if (port->membase == NULL) 533 return -ENOMEM; 534 } 535 return 0; 536 } 537 538 static void 539 lqasc_config_port(struct uart_port *port, int flags) 540 { 541 if (flags & UART_CONFIG_TYPE) { 542 port->type = PORT_LTQ_ASC; 543 lqasc_request_port(port); 544 } 545 } 546 547 static int 548 lqasc_verify_port(struct uart_port *port, 549 struct serial_struct *ser) 550 { 551 int ret = 0; 552 if (ser->type != PORT_UNKNOWN && ser->type != PORT_LTQ_ASC) 553 ret = -EINVAL; 554 if (ser->irq < 0 || ser->irq >= NR_IRQS) 555 ret = -EINVAL; 556 if (ser->baud_base < 9600) 557 ret = -EINVAL; 558 return ret; 559 } 560 561 static const struct uart_ops lqasc_pops = { 562 .tx_empty = lqasc_tx_empty, 563 .set_mctrl = lqasc_set_mctrl, 564 .get_mctrl = lqasc_get_mctrl, 565 .stop_tx = lqasc_stop_tx, 566 .start_tx = lqasc_start_tx, 567 .stop_rx = lqasc_stop_rx, 568 .break_ctl = lqasc_break_ctl, 569 .startup = lqasc_startup, 570 .shutdown = lqasc_shutdown, 571 .set_termios = lqasc_set_termios, 572 .type = lqasc_type, 573 .release_port = lqasc_release_port, 574 .request_port = lqasc_request_port, 575 .config_port = lqasc_config_port, 576 .verify_port = lqasc_verify_port, 577 }; 578 579 #ifdef CONFIG_SERIAL_LANTIQ_CONSOLE 580 static void 581 lqasc_console_putchar(struct uart_port *port, unsigned char ch) 582 { 583 if (!port->membase) 584 return; 585 586 while (!lqasc_tx_ready(port)) 587 ; 588 589 writeb(ch, port->membase + LTQ_ASC_TBUF); 590 } 591 592 static void lqasc_serial_port_write(struct uart_port *port, const char *s, 593 u_int count) 594 { 595 uart_console_write(port, s, count, lqasc_console_putchar); 596 } 597 598 static void 599 lqasc_console_write(struct console *co, const char *s, u_int count) 600 { 601 struct ltq_uart_port *ltq_port; 602 unsigned long flags; 603 604 if (co->index >= MAXPORTS) 605 return; 606 607 ltq_port = lqasc_port[co->index]; 608 if (!ltq_port) 609 return; 610 611 spin_lock_irqsave(<q_port->lock, flags); 612 lqasc_serial_port_write(<q_port->port, s, count); 613 spin_unlock_irqrestore(<q_port->lock, flags); 614 } 615 616 static int __init 617 lqasc_console_setup(struct console *co, char *options) 618 { 619 struct ltq_uart_port *ltq_port; 620 struct uart_port *port; 621 int baud = 115200; 622 int bits = 8; 623 int parity = 'n'; 624 int flow = 'n'; 625 626 if (co->index >= MAXPORTS) 627 return -ENODEV; 628 629 ltq_port = lqasc_port[co->index]; 630 if (!ltq_port) 631 return -ENODEV; 632 633 port = <q_port->port; 634 635 if (!IS_ERR(ltq_port->clk)) 636 clk_prepare_enable(ltq_port->clk); 637 638 port->uartclk = clk_get_rate(ltq_port->freqclk); 639 640 if (options) 641 uart_parse_options(options, &baud, &parity, &bits, &flow); 642 return uart_set_options(port, co, baud, parity, bits, flow); 643 } 644 645 static struct console lqasc_console = { 646 .name = "ttyLTQ", 647 .write = lqasc_console_write, 648 .device = uart_console_device, 649 .setup = lqasc_console_setup, 650 .flags = CON_PRINTBUFFER, 651 .index = -1, 652 .data = &lqasc_reg, 653 }; 654 655 static int __init 656 lqasc_console_init(void) 657 { 658 register_console(&lqasc_console); 659 return 0; 660 } 661 console_initcall(lqasc_console_init); 662 663 static void lqasc_serial_early_console_write(struct console *co, 664 const char *s, 665 u_int count) 666 { 667 struct earlycon_device *dev = co->data; 668 669 lqasc_serial_port_write(&dev->port, s, count); 670 } 671 672 static int __init 673 lqasc_serial_early_console_setup(struct earlycon_device *device, 674 const char *opt) 675 { 676 if (!device->port.membase) 677 return -ENODEV; 678 679 device->con->write = lqasc_serial_early_console_write; 680 return 0; 681 } 682 OF_EARLYCON_DECLARE(lantiq, "lantiq,asc", lqasc_serial_early_console_setup); 683 OF_EARLYCON_DECLARE(lantiq, "intel,lgm-asc", lqasc_serial_early_console_setup); 684 685 #define LANTIQ_SERIAL_CONSOLE (&lqasc_console) 686 687 #else 688 689 #define LANTIQ_SERIAL_CONSOLE NULL 690 691 #endif /* CONFIG_SERIAL_LANTIQ_CONSOLE */ 692 693 static struct uart_driver lqasc_reg = { 694 .owner = THIS_MODULE, 695 .driver_name = DRVNAME, 696 .dev_name = "ttyLTQ", 697 .major = 0, 698 .minor = 0, 699 .nr = MAXPORTS, 700 .cons = LANTIQ_SERIAL_CONSOLE, 701 }; 702 703 static int fetch_irq_lantiq(struct device *dev, struct ltq_uart_port *ltq_port) 704 { 705 struct uart_port *port = <q_port->port; 706 struct platform_device *pdev = to_platform_device(dev); 707 int irq; 708 709 irq = platform_get_irq(pdev, 0); 710 if (irq < 0) 711 return irq; 712 ltq_port->tx_irq = irq; 713 irq = platform_get_irq(pdev, 1); 714 if (irq < 0) 715 return irq; 716 ltq_port->rx_irq = irq; 717 irq = platform_get_irq(pdev, 2); 718 if (irq < 0) 719 return irq; 720 ltq_port->err_irq = irq; 721 722 port->irq = ltq_port->tx_irq; 723 724 return 0; 725 } 726 727 static int request_irq_lantiq(struct uart_port *port) 728 { 729 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 730 int retval; 731 732 retval = request_irq(ltq_port->tx_irq, lqasc_tx_int, 733 0, "asc_tx", port); 734 if (retval) { 735 dev_err(port->dev, "failed to request asc_tx\n"); 736 return retval; 737 } 738 739 retval = request_irq(ltq_port->rx_irq, lqasc_rx_int, 740 0, "asc_rx", port); 741 if (retval) { 742 dev_err(port->dev, "failed to request asc_rx\n"); 743 goto err1; 744 } 745 746 retval = request_irq(ltq_port->err_irq, lqasc_err_int, 747 0, "asc_err", port); 748 if (retval) { 749 dev_err(port->dev, "failed to request asc_err\n"); 750 goto err2; 751 } 752 return 0; 753 754 err2: 755 free_irq(ltq_port->rx_irq, port); 756 err1: 757 free_irq(ltq_port->tx_irq, port); 758 return retval; 759 } 760 761 static void free_irq_lantiq(struct uart_port *port) 762 { 763 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 764 765 free_irq(ltq_port->tx_irq, port); 766 free_irq(ltq_port->rx_irq, port); 767 free_irq(ltq_port->err_irq, port); 768 } 769 770 static int fetch_irq_intel(struct device *dev, struct ltq_uart_port *ltq_port) 771 { 772 struct uart_port *port = <q_port->port; 773 int ret; 774 775 ret = platform_get_irq(to_platform_device(dev), 0); 776 if (ret < 0) { 777 dev_err(dev, "failed to fetch IRQ for serial port\n"); 778 return ret; 779 } 780 ltq_port->common_irq = ret; 781 port->irq = ret; 782 783 return 0; 784 } 785 786 static int request_irq_intel(struct uart_port *port) 787 { 788 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 789 int retval; 790 791 retval = request_irq(ltq_port->common_irq, lqasc_irq, 0, 792 "asc_irq", port); 793 if (retval) 794 dev_err(port->dev, "failed to request asc_irq\n"); 795 796 return retval; 797 } 798 799 static void free_irq_intel(struct uart_port *port) 800 { 801 struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); 802 803 free_irq(ltq_port->common_irq, port); 804 } 805 806 static int lqasc_probe(struct platform_device *pdev) 807 { 808 struct device_node *node = pdev->dev.of_node; 809 struct ltq_uart_port *ltq_port; 810 struct uart_port *port; 811 struct resource *mmres; 812 int line; 813 int ret; 814 815 mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); 816 if (!mmres) { 817 dev_err(&pdev->dev, 818 "failed to get memory for serial port\n"); 819 return -ENODEV; 820 } 821 822 ltq_port = devm_kzalloc(&pdev->dev, sizeof(struct ltq_uart_port), 823 GFP_KERNEL); 824 if (!ltq_port) 825 return -ENOMEM; 826 827 port = <q_port->port; 828 829 ltq_port->soc = of_device_get_match_data(&pdev->dev); 830 ret = ltq_port->soc->fetch_irq(&pdev->dev, ltq_port); 831 if (ret) 832 return ret; 833 834 /* get serial id */ 835 line = of_alias_get_id(node, "serial"); 836 if (line < 0) { 837 if (IS_ENABLED(CONFIG_LANTIQ)) { 838 if (mmres->start == CPHYSADDR(LTQ_EARLY_ASC)) 839 line = 0; 840 else 841 line = 1; 842 } else { 843 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", 844 line); 845 return line; 846 } 847 } 848 849 if (lqasc_port[line]) { 850 dev_err(&pdev->dev, "port %d already allocated\n", line); 851 return -EBUSY; 852 } 853 854 port->iotype = SERIAL_IO_MEM; 855 port->flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP; 856 port->ops = &lqasc_pops; 857 port->fifosize = 16; 858 port->type = PORT_LTQ_ASC; 859 port->line = line; 860 port->dev = &pdev->dev; 861 /* unused, just to be backward-compatible */ 862 port->mapbase = mmres->start; 863 864 if (IS_ENABLED(CONFIG_LANTIQ) && !IS_ENABLED(CONFIG_COMMON_CLK)) 865 ltq_port->freqclk = clk_get_fpi(); 866 else 867 ltq_port->freqclk = devm_clk_get(&pdev->dev, "freq"); 868 869 870 if (IS_ERR(ltq_port->freqclk)) { 871 pr_err("failed to get fpi clk\n"); 872 return -ENOENT; 873 } 874 875 /* not all asc ports have clock gates, lets ignore the return code */ 876 if (IS_ENABLED(CONFIG_LANTIQ) && !IS_ENABLED(CONFIG_COMMON_CLK)) 877 ltq_port->clk = clk_get(&pdev->dev, NULL); 878 else 879 ltq_port->clk = devm_clk_get(&pdev->dev, "asc"); 880 881 spin_lock_init(<q_port->lock); 882 lqasc_port[line] = ltq_port; 883 platform_set_drvdata(pdev, ltq_port); 884 885 ret = uart_add_one_port(&lqasc_reg, port); 886 887 return ret; 888 } 889 890 static void lqasc_remove(struct platform_device *pdev) 891 { 892 struct uart_port *port = platform_get_drvdata(pdev); 893 894 uart_remove_one_port(&lqasc_reg, port); 895 } 896 897 static const struct ltq_soc_data soc_data_lantiq = { 898 .fetch_irq = fetch_irq_lantiq, 899 .request_irq = request_irq_lantiq, 900 .free_irq = free_irq_lantiq, 901 }; 902 903 static const struct ltq_soc_data soc_data_intel = { 904 .fetch_irq = fetch_irq_intel, 905 .request_irq = request_irq_intel, 906 .free_irq = free_irq_intel, 907 }; 908 909 static const struct of_device_id ltq_asc_match[] = { 910 { .compatible = "lantiq,asc", .data = &soc_data_lantiq }, 911 { .compatible = "intel,lgm-asc", .data = &soc_data_intel }, 912 {}, 913 }; 914 MODULE_DEVICE_TABLE(of, ltq_asc_match); 915 916 static struct platform_driver lqasc_driver = { 917 .probe = lqasc_probe, 918 .remove = lqasc_remove, 919 .driver = { 920 .name = DRVNAME, 921 .of_match_table = ltq_asc_match, 922 }, 923 }; 924 925 static int __init 926 init_lqasc(void) 927 { 928 int ret; 929 930 ret = uart_register_driver(&lqasc_reg); 931 if (ret != 0) 932 return ret; 933 934 ret = platform_driver_register(&lqasc_driver); 935 if (ret != 0) 936 uart_unregister_driver(&lqasc_reg); 937 938 return ret; 939 } 940 941 static void __exit exit_lqasc(void) 942 { 943 platform_driver_unregister(&lqasc_driver); 944 uart_unregister_driver(&lqasc_reg); 945 } 946 947 module_init(init_lqasc); 948 module_exit(exit_lqasc); 949 950 MODULE_DESCRIPTION("Serial driver for Lantiq & Intel gateway SoCs"); 951 MODULE_LICENSE("GPL v2"); 952