1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Synopsys DesignWare 8250 driver. 4 * 5 * Copyright 2011 Picochip, Jamie Iles. 6 * Copyright 2013 Intel Corporation 7 * 8 * The Synopsys DesignWare 8250 has an extra feature whereby it detects if the 9 * LCR is written whilst busy. If it is, then a busy detect interrupt is 10 * raised, the LCR needs to be rewritten and the uart status register read. 11 */ 12 #include <linux/delay.h> 13 #include <linux/device.h> 14 #include <linux/io.h> 15 #include <linux/mod_devicetable.h> 16 #include <linux/module.h> 17 #include <linux/serial_8250.h> 18 #include <linux/serial_reg.h> 19 #include <linux/of.h> 20 #include <linux/platform_device.h> 21 #include <linux/property.h> 22 #include <linux/workqueue.h> 23 #include <linux/notifier.h> 24 #include <linux/slab.h> 25 #include <linux/acpi.h> 26 #include <linux/clk.h> 27 #include <linux/reset.h> 28 #include <linux/pm_runtime.h> 29 30 #include <asm/byteorder.h> 31 32 #include "8250_dwlib.h" 33 34 /* Offsets for the DesignWare specific registers */ 35 #define DW_UART_USR 0x1f /* UART Status Register */ 36 #define DW_UART_DMASA 0xa8 /* DMA Software Ack */ 37 38 #define OCTEON_UART_USR 0x27 /* UART Status Register */ 39 40 #define RZN1_UART_TDMACR 0x10c /* DMA Control Register Transmit Mode */ 41 #define RZN1_UART_RDMACR 0x110 /* DMA Control Register Receive Mode */ 42 43 /* DesignWare specific register fields */ 44 #define DW_UART_MCR_SIRE BIT(6) 45 46 /* Renesas specific register fields */ 47 #define RZN1_UART_xDMACR_DMA_EN BIT(0) 48 #define RZN1_UART_xDMACR_1_WORD_BURST (0 << 1) 49 #define RZN1_UART_xDMACR_4_WORD_BURST (1 << 1) 50 #define RZN1_UART_xDMACR_8_WORD_BURST (3 << 1) 51 #define RZN1_UART_xDMACR_BLK_SZ(x) ((x) << 3) 52 53 /* Quirks */ 54 #define DW_UART_QUIRK_OCTEON BIT(0) 55 #define DW_UART_QUIRK_ARMADA_38X BIT(1) 56 #define DW_UART_QUIRK_SKIP_SET_RATE BIT(2) 57 #define DW_UART_QUIRK_IS_DMA_FC BIT(3) 58 59 static inline struct dw8250_data *clk_to_dw8250_data(struct notifier_block *nb) 60 { 61 return container_of(nb, struct dw8250_data, clk_notifier); 62 } 63 64 static inline struct dw8250_data *work_to_dw8250_data(struct work_struct *work) 65 { 66 return container_of(work, struct dw8250_data, clk_work); 67 } 68 69 static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value) 70 { 71 struct dw8250_data *d = to_dw8250_data(p->private_data); 72 73 /* Override any modem control signals if needed */ 74 if (offset == UART_MSR) { 75 value |= d->msr_mask_on; 76 value &= ~d->msr_mask_off; 77 } 78 79 return value; 80 } 81 82 static void dw8250_force_idle(struct uart_port *p) 83 { 84 struct uart_8250_port *up = up_to_u8250p(p); 85 86 serial8250_clear_and_reinit_fifos(up); 87 (void)p->serial_in(p, UART_RX); 88 } 89 90 static void dw8250_check_lcr(struct uart_port *p, int value) 91 { 92 void __iomem *offset = p->membase + (UART_LCR << p->regshift); 93 int tries = 1000; 94 95 /* Make sure LCR write wasn't ignored */ 96 while (tries--) { 97 unsigned int lcr = p->serial_in(p, UART_LCR); 98 99 if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR)) 100 return; 101 102 dw8250_force_idle(p); 103 104 #ifdef CONFIG_64BIT 105 if (p->type == PORT_OCTEON) 106 __raw_writeq(value & 0xff, offset); 107 else 108 #endif 109 if (p->iotype == UPIO_MEM32) 110 writel(value, offset); 111 else if (p->iotype == UPIO_MEM32BE) 112 iowrite32be(value, offset); 113 else 114 writeb(value, offset); 115 } 116 /* 117 * FIXME: this deadlocks if port->lock is already held 118 * dev_err(p->dev, "Couldn't set LCR to %d\n", value); 119 */ 120 } 121 122 /* Returns once the transmitter is empty or we run out of retries */ 123 static void dw8250_tx_wait_empty(struct uart_port *p) 124 { 125 unsigned int tries = 20000; 126 unsigned int delay_threshold = tries - 1000; 127 unsigned int lsr; 128 129 while (tries--) { 130 lsr = readb (p->membase + (UART_LSR << p->regshift)); 131 if (lsr & UART_LSR_TEMT) 132 break; 133 134 /* The device is first given a chance to empty without delay, 135 * to avoid slowdowns at high bitrates. If after 1000 tries 136 * the buffer has still not emptied, allow more time for low- 137 * speed links. */ 138 if (tries < delay_threshold) 139 udelay (1); 140 } 141 } 142 143 static void dw8250_serial_out38x(struct uart_port *p, int offset, int value) 144 { 145 struct dw8250_data *d = to_dw8250_data(p->private_data); 146 147 /* Allow the TX to drain before we reconfigure */ 148 if (offset == UART_LCR) 149 dw8250_tx_wait_empty(p); 150 151 writeb(value, p->membase + (offset << p->regshift)); 152 153 if (offset == UART_LCR && !d->uart_16550_compatible) 154 dw8250_check_lcr(p, value); 155 } 156 157 158 static void dw8250_serial_out(struct uart_port *p, int offset, int value) 159 { 160 struct dw8250_data *d = to_dw8250_data(p->private_data); 161 162 writeb(value, p->membase + (offset << p->regshift)); 163 164 if (offset == UART_LCR && !d->uart_16550_compatible) 165 dw8250_check_lcr(p, value); 166 } 167 168 static unsigned int dw8250_serial_in(struct uart_port *p, int offset) 169 { 170 unsigned int value = readb(p->membase + (offset << p->regshift)); 171 172 return dw8250_modify_msr(p, offset, value); 173 } 174 175 #ifdef CONFIG_64BIT 176 static unsigned int dw8250_serial_inq(struct uart_port *p, int offset) 177 { 178 unsigned int value; 179 180 value = (u8)__raw_readq(p->membase + (offset << p->regshift)); 181 182 return dw8250_modify_msr(p, offset, value); 183 } 184 185 static void dw8250_serial_outq(struct uart_port *p, int offset, int value) 186 { 187 struct dw8250_data *d = to_dw8250_data(p->private_data); 188 189 value &= 0xff; 190 __raw_writeq(value, p->membase + (offset << p->regshift)); 191 /* Read back to ensure register write ordering. */ 192 __raw_readq(p->membase + (UART_LCR << p->regshift)); 193 194 if (offset == UART_LCR && !d->uart_16550_compatible) 195 dw8250_check_lcr(p, value); 196 } 197 #endif /* CONFIG_64BIT */ 198 199 static void dw8250_serial_out32(struct uart_port *p, int offset, int value) 200 { 201 struct dw8250_data *d = to_dw8250_data(p->private_data); 202 203 writel(value, p->membase + (offset << p->regshift)); 204 205 if (offset == UART_LCR && !d->uart_16550_compatible) 206 dw8250_check_lcr(p, value); 207 } 208 209 static unsigned int dw8250_serial_in32(struct uart_port *p, int offset) 210 { 211 unsigned int value = readl(p->membase + (offset << p->regshift)); 212 213 return dw8250_modify_msr(p, offset, value); 214 } 215 216 static void dw8250_serial_out32be(struct uart_port *p, int offset, int value) 217 { 218 struct dw8250_data *d = to_dw8250_data(p->private_data); 219 220 iowrite32be(value, p->membase + (offset << p->regshift)); 221 222 if (offset == UART_LCR && !d->uart_16550_compatible) 223 dw8250_check_lcr(p, value); 224 } 225 226 static unsigned int dw8250_serial_in32be(struct uart_port *p, int offset) 227 { 228 unsigned int value = ioread32be(p->membase + (offset << p->regshift)); 229 230 return dw8250_modify_msr(p, offset, value); 231 } 232 233 234 static int dw8250_handle_irq(struct uart_port *p) 235 { 236 struct uart_8250_port *up = up_to_u8250p(p); 237 struct dw8250_data *d = to_dw8250_data(p->private_data); 238 unsigned int iir = p->serial_in(p, UART_IIR); 239 bool rx_timeout = (iir & 0x3f) == UART_IIR_RX_TIMEOUT; 240 unsigned int quirks = d->pdata->quirks; 241 unsigned int status; 242 unsigned long flags; 243 244 /* 245 * There are ways to get Designware-based UARTs into a state where 246 * they are asserting UART_IIR_RX_TIMEOUT but there is no actual 247 * data available. If we see such a case then we'll do a bogus 248 * read. If we don't do this then the "RX TIMEOUT" interrupt will 249 * fire forever. 250 * 251 * This problem has only been observed so far when not in DMA mode 252 * so we limit the workaround only to non-DMA mode. 253 */ 254 if (!up->dma && rx_timeout) { 255 spin_lock_irqsave(&p->lock, flags); 256 status = p->serial_in(p, UART_LSR); 257 258 if (!(status & (UART_LSR_DR | UART_LSR_BI))) 259 (void) p->serial_in(p, UART_RX); 260 261 spin_unlock_irqrestore(&p->lock, flags); 262 } 263 264 /* Manually stop the Rx DMA transfer when acting as flow controller */ 265 if (quirks & DW_UART_QUIRK_IS_DMA_FC && up->dma && up->dma->rx_running && rx_timeout) { 266 status = p->serial_in(p, UART_LSR); 267 if (status & (UART_LSR_DR | UART_LSR_BI)) { 268 dw8250_writel_ext(p, RZN1_UART_RDMACR, 0); 269 dw8250_writel_ext(p, DW_UART_DMASA, 1); 270 } 271 } 272 273 if (serial8250_handle_irq(p, iir)) 274 return 1; 275 276 if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) { 277 /* Clear the USR */ 278 (void)p->serial_in(p, d->pdata->usr_reg); 279 280 return 1; 281 } 282 283 return 0; 284 } 285 286 static void dw8250_clk_work_cb(struct work_struct *work) 287 { 288 struct dw8250_data *d = work_to_dw8250_data(work); 289 struct uart_8250_port *up; 290 unsigned long rate; 291 292 rate = clk_get_rate(d->clk); 293 if (rate <= 0) 294 return; 295 296 up = serial8250_get_port(d->data.line); 297 298 serial8250_update_uartclk(&up->port, rate); 299 } 300 301 static int dw8250_clk_notifier_cb(struct notifier_block *nb, 302 unsigned long event, void *data) 303 { 304 struct dw8250_data *d = clk_to_dw8250_data(nb); 305 306 /* 307 * We have no choice but to defer the uartclk update due to two 308 * deadlocks. First one is caused by a recursive mutex lock which 309 * happens when clk_set_rate() is called from dw8250_set_termios(). 310 * Second deadlock is more tricky and is caused by an inverted order of 311 * the clk and tty-port mutexes lock. It happens if clock rate change 312 * is requested asynchronously while set_termios() is executed between 313 * tty-port mutex lock and clk_set_rate() function invocation and 314 * vise-versa. Anyway if we didn't have the reference clock alteration 315 * in the dw8250_set_termios() method we wouldn't have needed this 316 * deferred event handling complication. 317 */ 318 if (event == POST_RATE_CHANGE) { 319 queue_work(system_unbound_wq, &d->clk_work); 320 return NOTIFY_OK; 321 } 322 323 return NOTIFY_DONE; 324 } 325 326 static void 327 dw8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old) 328 { 329 if (!state) 330 pm_runtime_get_sync(port->dev); 331 332 serial8250_do_pm(port, state, old); 333 334 if (state) 335 pm_runtime_put_sync_suspend(port->dev); 336 } 337 338 static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios, 339 struct ktermios *old) 340 { 341 unsigned long newrate = tty_termios_baud_rate(termios) * 16; 342 struct dw8250_data *d = to_dw8250_data(p->private_data); 343 long rate; 344 int ret; 345 346 clk_disable_unprepare(d->clk); 347 rate = clk_round_rate(d->clk, newrate); 348 if (rate > 0) { 349 /* 350 * Note that any clock-notifer worker will block in 351 * serial8250_update_uartclk() until we are done. 352 */ 353 ret = clk_set_rate(d->clk, newrate); 354 if (!ret) 355 p->uartclk = rate; 356 } 357 clk_prepare_enable(d->clk); 358 359 dw8250_do_set_termios(p, termios, old); 360 } 361 362 static void dw8250_set_ldisc(struct uart_port *p, struct ktermios *termios) 363 { 364 struct uart_8250_port *up = up_to_u8250p(p); 365 unsigned int mcr = p->serial_in(p, UART_MCR); 366 367 if (up->capabilities & UART_CAP_IRDA) { 368 if (termios->c_line == N_IRDA) 369 mcr |= DW_UART_MCR_SIRE; 370 else 371 mcr &= ~DW_UART_MCR_SIRE; 372 373 p->serial_out(p, UART_MCR, mcr); 374 } 375 serial8250_do_set_ldisc(p, termios); 376 } 377 378 /* 379 * dw8250_fallback_dma_filter will prevent the UART from getting just any free 380 * channel on platforms that have DMA engines, but don't have any channels 381 * assigned to the UART. 382 * 383 * REVISIT: This is a work around for limitation in the DMA Engine API. Once the 384 * core problem is fixed, this function is no longer needed. 385 */ 386 static bool dw8250_fallback_dma_filter(struct dma_chan *chan, void *param) 387 { 388 return false; 389 } 390 391 static bool dw8250_idma_filter(struct dma_chan *chan, void *param) 392 { 393 return param == chan->device->dev; 394 } 395 396 static u32 dw8250_rzn1_get_dmacr_burst(int max_burst) 397 { 398 if (max_burst >= 8) 399 return RZN1_UART_xDMACR_8_WORD_BURST; 400 else if (max_burst >= 4) 401 return RZN1_UART_xDMACR_4_WORD_BURST; 402 else 403 return RZN1_UART_xDMACR_1_WORD_BURST; 404 } 405 406 static void dw8250_prepare_tx_dma(struct uart_8250_port *p) 407 { 408 struct uart_port *up = &p->port; 409 struct uart_8250_dma *dma = p->dma; 410 u32 val; 411 412 dw8250_writel_ext(up, RZN1_UART_TDMACR, 0); 413 val = dw8250_rzn1_get_dmacr_burst(dma->txconf.dst_maxburst) | 414 RZN1_UART_xDMACR_BLK_SZ(dma->tx_size) | 415 RZN1_UART_xDMACR_DMA_EN; 416 dw8250_writel_ext(up, RZN1_UART_TDMACR, val); 417 } 418 419 static void dw8250_prepare_rx_dma(struct uart_8250_port *p) 420 { 421 struct uart_port *up = &p->port; 422 struct uart_8250_dma *dma = p->dma; 423 u32 val; 424 425 dw8250_writel_ext(up, RZN1_UART_RDMACR, 0); 426 val = dw8250_rzn1_get_dmacr_burst(dma->rxconf.src_maxburst) | 427 RZN1_UART_xDMACR_BLK_SZ(dma->rx_size) | 428 RZN1_UART_xDMACR_DMA_EN; 429 dw8250_writel_ext(up, RZN1_UART_RDMACR, val); 430 } 431 432 static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data) 433 { 434 struct device_node *np = p->dev->of_node; 435 436 if (np) { 437 unsigned int quirks = data->pdata->quirks; 438 int id; 439 440 /* get index of serial line, if found in DT aliases */ 441 id = of_alias_get_id(np, "serial"); 442 if (id >= 0) 443 p->line = id; 444 #ifdef CONFIG_64BIT 445 if (quirks & DW_UART_QUIRK_OCTEON) { 446 p->serial_in = dw8250_serial_inq; 447 p->serial_out = dw8250_serial_outq; 448 p->flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE; 449 p->type = PORT_OCTEON; 450 data->skip_autocfg = true; 451 } 452 #endif 453 454 if (of_device_is_big_endian(np)) { 455 p->iotype = UPIO_MEM32BE; 456 p->serial_in = dw8250_serial_in32be; 457 p->serial_out = dw8250_serial_out32be; 458 } 459 460 if (quirks & DW_UART_QUIRK_ARMADA_38X) 461 p->serial_out = dw8250_serial_out38x; 462 if (quirks & DW_UART_QUIRK_SKIP_SET_RATE) 463 p->set_termios = dw8250_do_set_termios; 464 if (quirks & DW_UART_QUIRK_IS_DMA_FC) { 465 data->data.dma.txconf.device_fc = 1; 466 data->data.dma.rxconf.device_fc = 1; 467 data->data.dma.prepare_tx_dma = dw8250_prepare_tx_dma; 468 data->data.dma.prepare_rx_dma = dw8250_prepare_rx_dma; 469 } 470 471 } else if (acpi_dev_present("APMC0D08", NULL, -1)) { 472 p->iotype = UPIO_MEM32; 473 p->regshift = 2; 474 p->serial_in = dw8250_serial_in32; 475 data->uart_16550_compatible = true; 476 } 477 478 /* Platforms with iDMA 64-bit */ 479 if (platform_get_resource_byname(to_platform_device(p->dev), 480 IORESOURCE_MEM, "lpss_priv")) { 481 data->data.dma.rx_param = p->dev->parent; 482 data->data.dma.tx_param = p->dev->parent; 483 data->data.dma.fn = dw8250_idma_filter; 484 } 485 } 486 487 static void dw8250_clk_disable_unprepare(void *data) 488 { 489 clk_disable_unprepare(data); 490 } 491 492 static void dw8250_reset_control_assert(void *data) 493 { 494 reset_control_assert(data); 495 } 496 497 static int dw8250_probe(struct platform_device *pdev) 498 { 499 struct uart_8250_port uart = {}, *up = &uart; 500 struct uart_port *p = &up->port; 501 struct device *dev = &pdev->dev; 502 struct dw8250_data *data; 503 struct resource *regs; 504 int irq; 505 int err; 506 u32 val; 507 508 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); 509 if (!regs) 510 return dev_err_probe(dev, -EINVAL, "no registers defined\n"); 511 512 irq = platform_get_irq(pdev, 0); 513 if (irq < 0) 514 return irq; 515 516 spin_lock_init(&p->lock); 517 p->mapbase = regs->start; 518 p->irq = irq; 519 p->handle_irq = dw8250_handle_irq; 520 p->pm = dw8250_do_pm; 521 p->type = PORT_8250; 522 p->flags = UPF_SHARE_IRQ | UPF_FIXED_PORT; 523 p->dev = dev; 524 p->iotype = UPIO_MEM; 525 p->serial_in = dw8250_serial_in; 526 p->serial_out = dw8250_serial_out; 527 p->set_ldisc = dw8250_set_ldisc; 528 p->set_termios = dw8250_set_termios; 529 530 p->membase = devm_ioremap(dev, regs->start, resource_size(regs)); 531 if (!p->membase) 532 return -ENOMEM; 533 534 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 535 if (!data) 536 return -ENOMEM; 537 538 data->data.dma.fn = dw8250_fallback_dma_filter; 539 data->pdata = device_get_match_data(p->dev); 540 p->private_data = &data->data; 541 542 data->uart_16550_compatible = device_property_read_bool(dev, 543 "snps,uart-16550-compatible"); 544 545 err = device_property_read_u32(dev, "reg-shift", &val); 546 if (!err) 547 p->regshift = val; 548 549 err = device_property_read_u32(dev, "reg-io-width", &val); 550 if (!err && val == 4) { 551 p->iotype = UPIO_MEM32; 552 p->serial_in = dw8250_serial_in32; 553 p->serial_out = dw8250_serial_out32; 554 } 555 556 if (device_property_read_bool(dev, "dcd-override")) { 557 /* Always report DCD as active */ 558 data->msr_mask_on |= UART_MSR_DCD; 559 data->msr_mask_off |= UART_MSR_DDCD; 560 } 561 562 if (device_property_read_bool(dev, "dsr-override")) { 563 /* Always report DSR as active */ 564 data->msr_mask_on |= UART_MSR_DSR; 565 data->msr_mask_off |= UART_MSR_DDSR; 566 } 567 568 if (device_property_read_bool(dev, "cts-override")) { 569 /* Always report CTS as active */ 570 data->msr_mask_on |= UART_MSR_CTS; 571 data->msr_mask_off |= UART_MSR_DCTS; 572 } 573 574 if (device_property_read_bool(dev, "ri-override")) { 575 /* Always report Ring indicator as inactive */ 576 data->msr_mask_off |= UART_MSR_RI; 577 data->msr_mask_off |= UART_MSR_TERI; 578 } 579 580 /* Always ask for fixed clock rate from a property. */ 581 device_property_read_u32(dev, "clock-frequency", &p->uartclk); 582 583 /* If there is separate baudclk, get the rate from it. */ 584 data->clk = devm_clk_get_optional(dev, "baudclk"); 585 if (data->clk == NULL) 586 data->clk = devm_clk_get_optional(dev, NULL); 587 if (IS_ERR(data->clk)) 588 return PTR_ERR(data->clk); 589 590 INIT_WORK(&data->clk_work, dw8250_clk_work_cb); 591 data->clk_notifier.notifier_call = dw8250_clk_notifier_cb; 592 593 err = clk_prepare_enable(data->clk); 594 if (err) 595 return dev_err_probe(dev, err, "could not enable optional baudclk\n"); 596 597 err = devm_add_action_or_reset(dev, dw8250_clk_disable_unprepare, data->clk); 598 if (err) 599 return err; 600 601 if (data->clk) 602 p->uartclk = clk_get_rate(data->clk); 603 604 /* If no clock rate is defined, fail. */ 605 if (!p->uartclk) 606 return dev_err_probe(dev, -EINVAL, "clock rate not defined\n"); 607 608 data->pclk = devm_clk_get_optional(dev, "apb_pclk"); 609 if (IS_ERR(data->pclk)) 610 return PTR_ERR(data->pclk); 611 612 err = clk_prepare_enable(data->pclk); 613 if (err) 614 return dev_err_probe(dev, err, "could not enable apb_pclk\n"); 615 616 err = devm_add_action_or_reset(dev, dw8250_clk_disable_unprepare, data->pclk); 617 if (err) 618 return err; 619 620 data->rst = devm_reset_control_get_optional_exclusive(dev, NULL); 621 if (IS_ERR(data->rst)) 622 return PTR_ERR(data->rst); 623 624 reset_control_deassert(data->rst); 625 626 err = devm_add_action_or_reset(dev, dw8250_reset_control_assert, data->rst); 627 if (err) 628 return err; 629 630 dw8250_quirks(p, data); 631 632 /* If the Busy Functionality is not implemented, don't handle it */ 633 if (data->uart_16550_compatible) 634 p->handle_irq = NULL; 635 636 if (!data->skip_autocfg) 637 dw8250_setup_port(p); 638 639 /* If we have a valid fifosize, try hooking up DMA */ 640 if (p->fifosize) { 641 data->data.dma.rxconf.src_maxburst = p->fifosize / 4; 642 data->data.dma.txconf.dst_maxburst = p->fifosize / 4; 643 up->dma = &data->data.dma; 644 } 645 646 data->data.line = serial8250_register_8250_port(up); 647 if (data->data.line < 0) 648 return data->data.line; 649 650 /* 651 * Some platforms may provide a reference clock shared between several 652 * devices. In this case any clock state change must be known to the 653 * UART port at least post factum. 654 */ 655 if (data->clk) { 656 err = clk_notifier_register(data->clk, &data->clk_notifier); 657 if (err) 658 return dev_err_probe(dev, err, "Failed to set the clock notifier\n"); 659 queue_work(system_unbound_wq, &data->clk_work); 660 } 661 662 platform_set_drvdata(pdev, data); 663 664 pm_runtime_set_active(dev); 665 pm_runtime_enable(dev); 666 667 return 0; 668 } 669 670 static int dw8250_remove(struct platform_device *pdev) 671 { 672 struct dw8250_data *data = platform_get_drvdata(pdev); 673 struct device *dev = &pdev->dev; 674 675 pm_runtime_get_sync(dev); 676 677 if (data->clk) { 678 clk_notifier_unregister(data->clk, &data->clk_notifier); 679 680 flush_work(&data->clk_work); 681 } 682 683 serial8250_unregister_port(data->data.line); 684 685 pm_runtime_disable(dev); 686 pm_runtime_put_noidle(dev); 687 688 return 0; 689 } 690 691 #ifdef CONFIG_PM_SLEEP 692 static int dw8250_suspend(struct device *dev) 693 { 694 struct dw8250_data *data = dev_get_drvdata(dev); 695 696 serial8250_suspend_port(data->data.line); 697 698 return 0; 699 } 700 701 static int dw8250_resume(struct device *dev) 702 { 703 struct dw8250_data *data = dev_get_drvdata(dev); 704 705 serial8250_resume_port(data->data.line); 706 707 return 0; 708 } 709 #endif /* CONFIG_PM_SLEEP */ 710 711 #ifdef CONFIG_PM 712 static int dw8250_runtime_suspend(struct device *dev) 713 { 714 struct dw8250_data *data = dev_get_drvdata(dev); 715 716 clk_disable_unprepare(data->clk); 717 718 clk_disable_unprepare(data->pclk); 719 720 return 0; 721 } 722 723 static int dw8250_runtime_resume(struct device *dev) 724 { 725 struct dw8250_data *data = dev_get_drvdata(dev); 726 727 clk_prepare_enable(data->pclk); 728 729 clk_prepare_enable(data->clk); 730 731 return 0; 732 } 733 #endif 734 735 static const struct dev_pm_ops dw8250_pm_ops = { 736 SET_SYSTEM_SLEEP_PM_OPS(dw8250_suspend, dw8250_resume) 737 SET_RUNTIME_PM_OPS(dw8250_runtime_suspend, dw8250_runtime_resume, NULL) 738 }; 739 740 static const struct dw8250_platform_data dw8250_dw_apb = { 741 .usr_reg = DW_UART_USR, 742 }; 743 744 static const struct dw8250_platform_data dw8250_octeon_3860_data = { 745 .usr_reg = OCTEON_UART_USR, 746 .quirks = DW_UART_QUIRK_OCTEON, 747 }; 748 749 static const struct dw8250_platform_data dw8250_armada_38x_data = { 750 .usr_reg = DW_UART_USR, 751 .quirks = DW_UART_QUIRK_ARMADA_38X, 752 }; 753 754 static const struct dw8250_platform_data dw8250_renesas_rzn1_data = { 755 .usr_reg = DW_UART_USR, 756 .cpr_val = 0x00012f32, 757 .quirks = DW_UART_QUIRK_IS_DMA_FC, 758 }; 759 760 static const struct dw8250_platform_data dw8250_starfive_jh7100_data = { 761 .usr_reg = DW_UART_USR, 762 .quirks = DW_UART_QUIRK_SKIP_SET_RATE, 763 }; 764 765 static const struct of_device_id dw8250_of_match[] = { 766 { .compatible = "snps,dw-apb-uart", .data = &dw8250_dw_apb }, 767 { .compatible = "cavium,octeon-3860-uart", .data = &dw8250_octeon_3860_data }, 768 { .compatible = "marvell,armada-38x-uart", .data = &dw8250_armada_38x_data }, 769 { .compatible = "renesas,rzn1-uart", .data = &dw8250_renesas_rzn1_data }, 770 { .compatible = "starfive,jh7100-uart", .data = &dw8250_starfive_jh7100_data }, 771 { /* Sentinel */ } 772 }; 773 MODULE_DEVICE_TABLE(of, dw8250_of_match); 774 775 static const struct acpi_device_id dw8250_acpi_match[] = { 776 { "INT33C4", 0 }, 777 { "INT33C5", 0 }, 778 { "INT3434", 0 }, 779 { "INT3435", 0 }, 780 { "80860F0A", 0 }, 781 { "8086228A", 0 }, 782 { "APMC0D08", 0}, 783 { "AMD0020", 0 }, 784 { "AMDI0020", 0 }, 785 { "AMDI0022", 0 }, 786 { "BRCM2032", 0 }, 787 { "HISI0031", 0 }, 788 { }, 789 }; 790 MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match); 791 792 static struct platform_driver dw8250_platform_driver = { 793 .driver = { 794 .name = "dw-apb-uart", 795 .pm = &dw8250_pm_ops, 796 .of_match_table = dw8250_of_match, 797 .acpi_match_table = dw8250_acpi_match, 798 }, 799 .probe = dw8250_probe, 800 .remove = dw8250_remove, 801 }; 802 803 module_platform_driver(dw8250_platform_driver); 804 805 MODULE_AUTHOR("Jamie Iles"); 806 MODULE_LICENSE("GPL"); 807 MODULE_DESCRIPTION("Synopsys DesignWare 8250 serial port driver"); 808 MODULE_ALIAS("platform:dw-apb-uart"); 809