1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Driver for AMBA serial ports 4 * 5 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. 6 * 7 * Copyright 1999 ARM Limited 8 * Copyright (C) 2000 Deep Blue Solutions Ltd. 9 * 10 * This is a generic driver for ARM AMBA-type serial ports. They 11 * have a lot of 16550-like features, but are not register compatible. 12 * Note that although they do have CTS, DCD and DSR inputs, they do 13 * not have an RI input, nor do they have DTR or RTS outputs. If 14 * required, these have to be supplied via some other means (eg, GPIO) 15 * and hooked into this driver. 16 */ 17 18 #include <linux/module.h> 19 #include <linux/ioport.h> 20 #include <linux/init.h> 21 #include <linux/console.h> 22 #include <linux/sysrq.h> 23 #include <linux/device.h> 24 #include <linux/tty.h> 25 #include <linux/tty_flip.h> 26 #include <linux/serial_core.h> 27 #include <linux/serial.h> 28 #include <linux/amba/bus.h> 29 #include <linux/amba/serial.h> 30 #include <linux/clk.h> 31 #include <linux/slab.h> 32 #include <linux/io.h> 33 34 #define UART_NR 8 35 36 #define SERIAL_AMBA_MAJOR 204 37 #define SERIAL_AMBA_MINOR 16 38 #define SERIAL_AMBA_NR UART_NR 39 40 #define AMBA_ISR_PASS_LIMIT 256 41 42 #define UART_RX_DATA(s) (((s) & UART01x_FR_RXFE) == 0) 43 #define UART_TX_READY(s) (((s) & UART01x_FR_TXFF) == 0) 44 45 #define UART_DUMMY_RSR_RX 256 46 #define UART_PORT_SIZE 64 47 48 /* 49 * We wrap our port structure around the generic uart_port. 50 */ 51 struct uart_amba_port { 52 struct uart_port port; 53 struct clk *clk; 54 struct amba_device *dev; 55 struct amba_pl010_data *data; 56 unsigned int old_status; 57 }; 58 59 static void pl010_stop_tx(struct uart_port *port) 60 { 61 struct uart_amba_port *uap = 62 container_of(port, struct uart_amba_port, port); 63 unsigned int cr; 64 65 cr = readb(uap->port.membase + UART010_CR); 66 cr &= ~UART010_CR_TIE; 67 writel(cr, uap->port.membase + UART010_CR); 68 } 69 70 static void pl010_start_tx(struct uart_port *port) 71 { 72 struct uart_amba_port *uap = 73 container_of(port, struct uart_amba_port, port); 74 unsigned int cr; 75 76 cr = readb(uap->port.membase + UART010_CR); 77 cr |= UART010_CR_TIE; 78 writel(cr, uap->port.membase + UART010_CR); 79 } 80 81 static void pl010_stop_rx(struct uart_port *port) 82 { 83 struct uart_amba_port *uap = 84 container_of(port, struct uart_amba_port, port); 85 unsigned int cr; 86 87 cr = readb(uap->port.membase + UART010_CR); 88 cr &= ~(UART010_CR_RIE | UART010_CR_RTIE); 89 writel(cr, uap->port.membase + UART010_CR); 90 } 91 92 static void pl010_disable_ms(struct uart_port *port) 93 { 94 struct uart_amba_port *uap = (struct uart_amba_port *)port; 95 unsigned int cr; 96 97 cr = readb(uap->port.membase + UART010_CR); 98 cr &= ~UART010_CR_MSIE; 99 writel(cr, uap->port.membase + UART010_CR); 100 } 101 102 static void pl010_enable_ms(struct uart_port *port) 103 { 104 struct uart_amba_port *uap = 105 container_of(port, struct uart_amba_port, port); 106 unsigned int cr; 107 108 cr = readb(uap->port.membase + UART010_CR); 109 cr |= UART010_CR_MSIE; 110 writel(cr, uap->port.membase + UART010_CR); 111 } 112 113 static void pl010_rx_chars(struct uart_amba_port *uap) 114 { 115 unsigned int status, ch, flag, rsr, max_count = 256; 116 117 status = readb(uap->port.membase + UART01x_FR); 118 while (UART_RX_DATA(status) && max_count--) { 119 ch = readb(uap->port.membase + UART01x_DR); 120 flag = TTY_NORMAL; 121 122 uap->port.icount.rx++; 123 124 /* 125 * Note that the error handling code is 126 * out of the main execution path 127 */ 128 rsr = readb(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX; 129 if (unlikely(rsr & UART01x_RSR_ANY)) { 130 writel(0, uap->port.membase + UART01x_ECR); 131 132 if (rsr & UART01x_RSR_BE) { 133 rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE); 134 uap->port.icount.brk++; 135 if (uart_handle_break(&uap->port)) 136 goto ignore_char; 137 } else if (rsr & UART01x_RSR_PE) 138 uap->port.icount.parity++; 139 else if (rsr & UART01x_RSR_FE) 140 uap->port.icount.frame++; 141 if (rsr & UART01x_RSR_OE) 142 uap->port.icount.overrun++; 143 144 rsr &= uap->port.read_status_mask; 145 146 if (rsr & UART01x_RSR_BE) 147 flag = TTY_BREAK; 148 else if (rsr & UART01x_RSR_PE) 149 flag = TTY_PARITY; 150 else if (rsr & UART01x_RSR_FE) 151 flag = TTY_FRAME; 152 } 153 154 if (uart_handle_sysrq_char(&uap->port, ch)) 155 goto ignore_char; 156 157 uart_insert_char(&uap->port, rsr, UART01x_RSR_OE, ch, flag); 158 159 ignore_char: 160 status = readb(uap->port.membase + UART01x_FR); 161 } 162 tty_flip_buffer_push(&uap->port.state->port); 163 } 164 165 static void pl010_tx_chars(struct uart_amba_port *uap) 166 { 167 struct circ_buf *xmit = &uap->port.state->xmit; 168 int count; 169 170 if (uap->port.x_char) { 171 writel(uap->port.x_char, uap->port.membase + UART01x_DR); 172 uap->port.icount.tx++; 173 uap->port.x_char = 0; 174 return; 175 } 176 if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) { 177 pl010_stop_tx(&uap->port); 178 return; 179 } 180 181 count = uap->port.fifosize >> 1; 182 do { 183 writel(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR); 184 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); 185 uap->port.icount.tx++; 186 if (uart_circ_empty(xmit)) 187 break; 188 } while (--count > 0); 189 190 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) 191 uart_write_wakeup(&uap->port); 192 193 if (uart_circ_empty(xmit)) 194 pl010_stop_tx(&uap->port); 195 } 196 197 static void pl010_modem_status(struct uart_amba_port *uap) 198 { 199 unsigned int status, delta; 200 201 writel(0, uap->port.membase + UART010_ICR); 202 203 status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY; 204 205 delta = status ^ uap->old_status; 206 uap->old_status = status; 207 208 if (!delta) 209 return; 210 211 if (delta & UART01x_FR_DCD) 212 uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD); 213 214 if (delta & UART01x_FR_DSR) 215 uap->port.icount.dsr++; 216 217 if (delta & UART01x_FR_CTS) 218 uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS); 219 220 wake_up_interruptible(&uap->port.state->port.delta_msr_wait); 221 } 222 223 static irqreturn_t pl010_int(int irq, void *dev_id) 224 { 225 struct uart_amba_port *uap = dev_id; 226 unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT; 227 int handled = 0; 228 229 spin_lock(&uap->port.lock); 230 231 status = readb(uap->port.membase + UART010_IIR); 232 if (status) { 233 do { 234 if (status & (UART010_IIR_RTIS | UART010_IIR_RIS)) 235 pl010_rx_chars(uap); 236 if (status & UART010_IIR_MIS) 237 pl010_modem_status(uap); 238 if (status & UART010_IIR_TIS) 239 pl010_tx_chars(uap); 240 241 if (pass_counter-- == 0) 242 break; 243 244 status = readb(uap->port.membase + UART010_IIR); 245 } while (status & (UART010_IIR_RTIS | UART010_IIR_RIS | 246 UART010_IIR_TIS)); 247 handled = 1; 248 } 249 250 spin_unlock(&uap->port.lock); 251 252 return IRQ_RETVAL(handled); 253 } 254 255 static unsigned int pl010_tx_empty(struct uart_port *port) 256 { 257 struct uart_amba_port *uap = 258 container_of(port, struct uart_amba_port, port); 259 unsigned int status = readb(uap->port.membase + UART01x_FR); 260 return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT; 261 } 262 263 static unsigned int pl010_get_mctrl(struct uart_port *port) 264 { 265 struct uart_amba_port *uap = 266 container_of(port, struct uart_amba_port, port); 267 unsigned int result = 0; 268 unsigned int status; 269 270 status = readb(uap->port.membase + UART01x_FR); 271 if (status & UART01x_FR_DCD) 272 result |= TIOCM_CAR; 273 if (status & UART01x_FR_DSR) 274 result |= TIOCM_DSR; 275 if (status & UART01x_FR_CTS) 276 result |= TIOCM_CTS; 277 278 return result; 279 } 280 281 static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl) 282 { 283 struct uart_amba_port *uap = 284 container_of(port, struct uart_amba_port, port); 285 286 if (uap->data) 287 uap->data->set_mctrl(uap->dev, uap->port.membase, mctrl); 288 } 289 290 static void pl010_break_ctl(struct uart_port *port, int break_state) 291 { 292 struct uart_amba_port *uap = 293 container_of(port, struct uart_amba_port, port); 294 unsigned long flags; 295 unsigned int lcr_h; 296 297 spin_lock_irqsave(&uap->port.lock, flags); 298 lcr_h = readb(uap->port.membase + UART010_LCRH); 299 if (break_state == -1) 300 lcr_h |= UART01x_LCRH_BRK; 301 else 302 lcr_h &= ~UART01x_LCRH_BRK; 303 writel(lcr_h, uap->port.membase + UART010_LCRH); 304 spin_unlock_irqrestore(&uap->port.lock, flags); 305 } 306 307 static int pl010_startup(struct uart_port *port) 308 { 309 struct uart_amba_port *uap = 310 container_of(port, struct uart_amba_port, port); 311 int retval; 312 313 /* 314 * Try to enable the clock producer. 315 */ 316 retval = clk_prepare_enable(uap->clk); 317 if (retval) 318 goto out; 319 320 uap->port.uartclk = clk_get_rate(uap->clk); 321 322 /* 323 * Allocate the IRQ 324 */ 325 retval = request_irq(uap->port.irq, pl010_int, 0, "uart-pl010", uap); 326 if (retval) 327 goto clk_dis; 328 329 /* 330 * initialise the old status of the modem signals 331 */ 332 uap->old_status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY; 333 334 /* 335 * Finally, enable interrupts 336 */ 337 writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE, 338 uap->port.membase + UART010_CR); 339 340 return 0; 341 342 clk_dis: 343 clk_disable_unprepare(uap->clk); 344 out: 345 return retval; 346 } 347 348 static void pl010_shutdown(struct uart_port *port) 349 { 350 struct uart_amba_port *uap = 351 container_of(port, struct uart_amba_port, port); 352 353 /* 354 * Free the interrupt 355 */ 356 free_irq(uap->port.irq, uap); 357 358 /* 359 * disable all interrupts, disable the port 360 */ 361 writel(0, uap->port.membase + UART010_CR); 362 363 /* disable break condition and fifos */ 364 writel(readb(uap->port.membase + UART010_LCRH) & 365 ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN), 366 uap->port.membase + UART010_LCRH); 367 368 /* 369 * Shut down the clock producer 370 */ 371 clk_disable_unprepare(uap->clk); 372 } 373 374 static void 375 pl010_set_termios(struct uart_port *port, struct ktermios *termios, 376 struct ktermios *old) 377 { 378 struct uart_amba_port *uap = 379 container_of(port, struct uart_amba_port, port); 380 unsigned int lcr_h, old_cr; 381 unsigned long flags; 382 unsigned int baud, quot; 383 384 /* 385 * Ask the core to calculate the divisor for us. 386 */ 387 baud = uart_get_baud_rate(port, termios, old, 0, uap->port.uartclk/16); 388 quot = uart_get_divisor(port, baud); 389 390 switch (termios->c_cflag & CSIZE) { 391 case CS5: 392 lcr_h = UART01x_LCRH_WLEN_5; 393 break; 394 case CS6: 395 lcr_h = UART01x_LCRH_WLEN_6; 396 break; 397 case CS7: 398 lcr_h = UART01x_LCRH_WLEN_7; 399 break; 400 default: // CS8 401 lcr_h = UART01x_LCRH_WLEN_8; 402 break; 403 } 404 if (termios->c_cflag & CSTOPB) 405 lcr_h |= UART01x_LCRH_STP2; 406 if (termios->c_cflag & PARENB) { 407 lcr_h |= UART01x_LCRH_PEN; 408 if (!(termios->c_cflag & PARODD)) 409 lcr_h |= UART01x_LCRH_EPS; 410 } 411 if (uap->port.fifosize > 1) 412 lcr_h |= UART01x_LCRH_FEN; 413 414 spin_lock_irqsave(&uap->port.lock, flags); 415 416 /* 417 * Update the per-port timeout. 418 */ 419 uart_update_timeout(port, termios->c_cflag, baud); 420 421 uap->port.read_status_mask = UART01x_RSR_OE; 422 if (termios->c_iflag & INPCK) 423 uap->port.read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE; 424 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) 425 uap->port.read_status_mask |= UART01x_RSR_BE; 426 427 /* 428 * Characters to ignore 429 */ 430 uap->port.ignore_status_mask = 0; 431 if (termios->c_iflag & IGNPAR) 432 uap->port.ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE; 433 if (termios->c_iflag & IGNBRK) { 434 uap->port.ignore_status_mask |= UART01x_RSR_BE; 435 /* 436 * If we're ignoring parity and break indicators, 437 * ignore overruns too (for real raw support). 438 */ 439 if (termios->c_iflag & IGNPAR) 440 uap->port.ignore_status_mask |= UART01x_RSR_OE; 441 } 442 443 /* 444 * Ignore all characters if CREAD is not set. 445 */ 446 if ((termios->c_cflag & CREAD) == 0) 447 uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX; 448 449 old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE; 450 451 if (UART_ENABLE_MS(port, termios->c_cflag)) 452 old_cr |= UART010_CR_MSIE; 453 454 /* Set baud rate */ 455 quot -= 1; 456 writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM); 457 writel(quot & 0xff, uap->port.membase + UART010_LCRL); 458 459 /* 460 * ----------v----------v----------v----------v----- 461 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L 462 * ----------^----------^----------^----------^----- 463 */ 464 writel(lcr_h, uap->port.membase + UART010_LCRH); 465 writel(old_cr, uap->port.membase + UART010_CR); 466 467 spin_unlock_irqrestore(&uap->port.lock, flags); 468 } 469 470 static void pl010_set_ldisc(struct uart_port *port, struct ktermios *termios) 471 { 472 if (termios->c_line == N_PPS) { 473 port->flags |= UPF_HARDPPS_CD; 474 spin_lock_irq(&port->lock); 475 pl010_enable_ms(port); 476 spin_unlock_irq(&port->lock); 477 } else { 478 port->flags &= ~UPF_HARDPPS_CD; 479 if (!UART_ENABLE_MS(port, termios->c_cflag)) { 480 spin_lock_irq(&port->lock); 481 pl010_disable_ms(port); 482 spin_unlock_irq(&port->lock); 483 } 484 } 485 } 486 487 static const char *pl010_type(struct uart_port *port) 488 { 489 return port->type == PORT_AMBA ? "AMBA" : NULL; 490 } 491 492 /* 493 * Release the memory region(s) being used by 'port' 494 */ 495 static void pl010_release_port(struct uart_port *port) 496 { 497 release_mem_region(port->mapbase, UART_PORT_SIZE); 498 } 499 500 /* 501 * Request the memory region(s) being used by 'port' 502 */ 503 static int pl010_request_port(struct uart_port *port) 504 { 505 return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010") 506 != NULL ? 0 : -EBUSY; 507 } 508 509 /* 510 * Configure/autoconfigure the port. 511 */ 512 static void pl010_config_port(struct uart_port *port, int flags) 513 { 514 if (flags & UART_CONFIG_TYPE) { 515 port->type = PORT_AMBA; 516 pl010_request_port(port); 517 } 518 } 519 520 /* 521 * verify the new serial_struct (for TIOCSSERIAL). 522 */ 523 static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser) 524 { 525 int ret = 0; 526 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA) 527 ret = -EINVAL; 528 if (ser->irq < 0 || ser->irq >= nr_irqs) 529 ret = -EINVAL; 530 if (ser->baud_base < 9600) 531 ret = -EINVAL; 532 return ret; 533 } 534 535 static const struct uart_ops amba_pl010_pops = { 536 .tx_empty = pl010_tx_empty, 537 .set_mctrl = pl010_set_mctrl, 538 .get_mctrl = pl010_get_mctrl, 539 .stop_tx = pl010_stop_tx, 540 .start_tx = pl010_start_tx, 541 .stop_rx = pl010_stop_rx, 542 .enable_ms = pl010_enable_ms, 543 .break_ctl = pl010_break_ctl, 544 .startup = pl010_startup, 545 .shutdown = pl010_shutdown, 546 .set_termios = pl010_set_termios, 547 .set_ldisc = pl010_set_ldisc, 548 .type = pl010_type, 549 .release_port = pl010_release_port, 550 .request_port = pl010_request_port, 551 .config_port = pl010_config_port, 552 .verify_port = pl010_verify_port, 553 }; 554 555 static struct uart_amba_port *amba_ports[UART_NR]; 556 557 #ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE 558 559 static void pl010_console_putchar(struct uart_port *port, int ch) 560 { 561 struct uart_amba_port *uap = 562 container_of(port, struct uart_amba_port, port); 563 unsigned int status; 564 565 do { 566 status = readb(uap->port.membase + UART01x_FR); 567 barrier(); 568 } while (!UART_TX_READY(status)); 569 writel(ch, uap->port.membase + UART01x_DR); 570 } 571 572 static void 573 pl010_console_write(struct console *co, const char *s, unsigned int count) 574 { 575 struct uart_amba_port *uap = amba_ports[co->index]; 576 unsigned int status, old_cr; 577 578 clk_enable(uap->clk); 579 580 /* 581 * First save the CR then disable the interrupts 582 */ 583 old_cr = readb(uap->port.membase + UART010_CR); 584 writel(UART01x_CR_UARTEN, uap->port.membase + UART010_CR); 585 586 uart_console_write(&uap->port, s, count, pl010_console_putchar); 587 588 /* 589 * Finally, wait for transmitter to become empty 590 * and restore the TCR 591 */ 592 do { 593 status = readb(uap->port.membase + UART01x_FR); 594 barrier(); 595 } while (status & UART01x_FR_BUSY); 596 writel(old_cr, uap->port.membase + UART010_CR); 597 598 clk_disable(uap->clk); 599 } 600 601 static void __init 602 pl010_console_get_options(struct uart_amba_port *uap, int *baud, 603 int *parity, int *bits) 604 { 605 if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) { 606 unsigned int lcr_h, quot; 607 lcr_h = readb(uap->port.membase + UART010_LCRH); 608 609 *parity = 'n'; 610 if (lcr_h & UART01x_LCRH_PEN) { 611 if (lcr_h & UART01x_LCRH_EPS) 612 *parity = 'e'; 613 else 614 *parity = 'o'; 615 } 616 617 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7) 618 *bits = 7; 619 else 620 *bits = 8; 621 622 quot = readb(uap->port.membase + UART010_LCRL) | 623 readb(uap->port.membase + UART010_LCRM) << 8; 624 *baud = uap->port.uartclk / (16 * (quot + 1)); 625 } 626 } 627 628 static int __init pl010_console_setup(struct console *co, char *options) 629 { 630 struct uart_amba_port *uap; 631 int baud = 38400; 632 int bits = 8; 633 int parity = 'n'; 634 int flow = 'n'; 635 int ret; 636 637 /* 638 * Check whether an invalid uart number has been specified, and 639 * if so, search for the first available port that does have 640 * console support. 641 */ 642 if (co->index >= UART_NR) 643 co->index = 0; 644 uap = amba_ports[co->index]; 645 if (!uap) 646 return -ENODEV; 647 648 ret = clk_prepare(uap->clk); 649 if (ret) 650 return ret; 651 652 uap->port.uartclk = clk_get_rate(uap->clk); 653 654 if (options) 655 uart_parse_options(options, &baud, &parity, &bits, &flow); 656 else 657 pl010_console_get_options(uap, &baud, &parity, &bits); 658 659 return uart_set_options(&uap->port, co, baud, parity, bits, flow); 660 } 661 662 static struct uart_driver amba_reg; 663 static struct console amba_console = { 664 .name = "ttyAM", 665 .write = pl010_console_write, 666 .device = uart_console_device, 667 .setup = pl010_console_setup, 668 .flags = CON_PRINTBUFFER, 669 .index = -1, 670 .data = &amba_reg, 671 }; 672 673 #define AMBA_CONSOLE &amba_console 674 #else 675 #define AMBA_CONSOLE NULL 676 #endif 677 678 static DEFINE_MUTEX(amba_reg_lock); 679 static struct uart_driver amba_reg = { 680 .owner = THIS_MODULE, 681 .driver_name = "ttyAM", 682 .dev_name = "ttyAM", 683 .major = SERIAL_AMBA_MAJOR, 684 .minor = SERIAL_AMBA_MINOR, 685 .nr = UART_NR, 686 .cons = AMBA_CONSOLE, 687 }; 688 689 static int pl010_probe(struct amba_device *dev, const struct amba_id *id) 690 { 691 struct uart_amba_port *uap; 692 void __iomem *base; 693 int i, ret; 694 695 for (i = 0; i < ARRAY_SIZE(amba_ports); i++) 696 if (amba_ports[i] == NULL) 697 break; 698 699 if (i == ARRAY_SIZE(amba_ports)) 700 return -EBUSY; 701 702 uap = devm_kzalloc(&dev->dev, sizeof(struct uart_amba_port), 703 GFP_KERNEL); 704 if (!uap) 705 return -ENOMEM; 706 707 base = devm_ioremap(&dev->dev, dev->res.start, 708 resource_size(&dev->res)); 709 if (!base) 710 return -ENOMEM; 711 712 uap->clk = devm_clk_get(&dev->dev, NULL); 713 if (IS_ERR(uap->clk)) 714 return PTR_ERR(uap->clk); 715 716 uap->port.dev = &dev->dev; 717 uap->port.mapbase = dev->res.start; 718 uap->port.membase = base; 719 uap->port.iotype = UPIO_MEM; 720 uap->port.irq = dev->irq[0]; 721 uap->port.fifosize = 16; 722 uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_AMBA_PL010_CONSOLE); 723 uap->port.ops = &amba_pl010_pops; 724 uap->port.flags = UPF_BOOT_AUTOCONF; 725 uap->port.line = i; 726 uap->dev = dev; 727 uap->data = dev_get_platdata(&dev->dev); 728 729 amba_ports[i] = uap; 730 731 amba_set_drvdata(dev, uap); 732 733 mutex_lock(&amba_reg_lock); 734 if (!amba_reg.state) { 735 ret = uart_register_driver(&amba_reg); 736 if (ret < 0) { 737 mutex_unlock(&amba_reg_lock); 738 dev_err(uap->port.dev, 739 "Failed to register AMBA-PL010 driver\n"); 740 return ret; 741 } 742 } 743 mutex_unlock(&amba_reg_lock); 744 745 ret = uart_add_one_port(&amba_reg, &uap->port); 746 if (ret) 747 amba_ports[i] = NULL; 748 749 return ret; 750 } 751 752 static void pl010_remove(struct amba_device *dev) 753 { 754 struct uart_amba_port *uap = amba_get_drvdata(dev); 755 int i; 756 bool busy = false; 757 758 uart_remove_one_port(&amba_reg, &uap->port); 759 760 for (i = 0; i < ARRAY_SIZE(amba_ports); i++) 761 if (amba_ports[i] == uap) 762 amba_ports[i] = NULL; 763 else if (amba_ports[i]) 764 busy = true; 765 766 if (!busy) 767 uart_unregister_driver(&amba_reg); 768 } 769 770 #ifdef CONFIG_PM_SLEEP 771 static int pl010_suspend(struct device *dev) 772 { 773 struct uart_amba_port *uap = dev_get_drvdata(dev); 774 775 if (uap) 776 uart_suspend_port(&amba_reg, &uap->port); 777 778 return 0; 779 } 780 781 static int pl010_resume(struct device *dev) 782 { 783 struct uart_amba_port *uap = dev_get_drvdata(dev); 784 785 if (uap) 786 uart_resume_port(&amba_reg, &uap->port); 787 788 return 0; 789 } 790 #endif 791 792 static SIMPLE_DEV_PM_OPS(pl010_dev_pm_ops, pl010_suspend, pl010_resume); 793 794 static const struct amba_id pl010_ids[] = { 795 { 796 .id = 0x00041010, 797 .mask = 0x000fffff, 798 }, 799 { 0, 0 }, 800 }; 801 802 MODULE_DEVICE_TABLE(amba, pl010_ids); 803 804 static struct amba_driver pl010_driver = { 805 .drv = { 806 .name = "uart-pl010", 807 .pm = &pl010_dev_pm_ops, 808 }, 809 .id_table = pl010_ids, 810 .probe = pl010_probe, 811 .remove = pl010_remove, 812 }; 813 814 static int __init pl010_init(void) 815 { 816 printk(KERN_INFO "Serial: AMBA driver\n"); 817 818 return amba_driver_register(&pl010_driver); 819 } 820 821 static void __exit pl010_exit(void) 822 { 823 amba_driver_unregister(&pl010_driver); 824 } 825 826 module_init(pl010_init); 827 module_exit(pl010_exit); 828 829 MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd"); 830 MODULE_DESCRIPTION("ARM AMBA serial port driver"); 831 MODULE_LICENSE("GPL"); 832