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