1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Mediatek 8250 driver. 4 * 5 * Copyright (c) 2014 MundoReader S.L. 6 * Author: Matthias Brugger <matthias.bgg@gmail.com> 7 */ 8 #include <linux/clk.h> 9 #include <linux/io.h> 10 #include <linux/module.h> 11 #include <linux/of_irq.h> 12 #include <linux/of_platform.h> 13 #include <linux/pinctrl/consumer.h> 14 #include <linux/platform_device.h> 15 #include <linux/pm_runtime.h> 16 #include <linux/serial_8250.h> 17 #include <linux/serial_reg.h> 18 #include <linux/console.h> 19 #include <linux/dma-mapping.h> 20 #include <linux/tty.h> 21 #include <linux/tty_flip.h> 22 23 #include "8250.h" 24 25 #define MTK_UART_HIGHS 0x09 /* Highspeed register */ 26 #define MTK_UART_SAMPLE_COUNT 0x0a /* Sample count register */ 27 #define MTK_UART_SAMPLE_POINT 0x0b /* Sample point register */ 28 #define MTK_UART_RATE_FIX 0x0d /* UART Rate Fix Register */ 29 #define MTK_UART_ESCAPE_DAT 0x10 /* Escape Character register */ 30 #define MTK_UART_ESCAPE_EN 0x11 /* Escape Enable register */ 31 #define MTK_UART_DMA_EN 0x13 /* DMA Enable register */ 32 #define MTK_UART_RXTRI_AD 0x14 /* RX Trigger address */ 33 #define MTK_UART_FRACDIV_L 0x15 /* Fractional divider LSB address */ 34 #define MTK_UART_FRACDIV_M 0x16 /* Fractional divider MSB address */ 35 #define MTK_UART_DEBUG0 0x18 36 #define MTK_UART_IER_XOFFI 0x20 /* Enable XOFF character interrupt */ 37 #define MTK_UART_IER_RTSI 0x40 /* Enable RTS Modem status interrupt */ 38 #define MTK_UART_IER_CTSI 0x80 /* Enable CTS Modem status interrupt */ 39 40 #define MTK_UART_EFR 38 /* I/O: Extended Features Register */ 41 #define MTK_UART_EFR_EN 0x10 /* Enable enhancement feature */ 42 #define MTK_UART_EFR_RTS 0x40 /* Enable hardware rx flow control */ 43 #define MTK_UART_EFR_CTS 0x80 /* Enable hardware tx flow control */ 44 #define MTK_UART_EFR_NO_SW_FC 0x0 /* no sw flow control */ 45 #define MTK_UART_EFR_XON1_XOFF1 0xa /* XON1/XOFF1 as sw flow control */ 46 #define MTK_UART_EFR_XON2_XOFF2 0x5 /* XON2/XOFF2 as sw flow control */ 47 #define MTK_UART_EFR_SW_FC_MASK 0xf /* Enable CTS Modem status interrupt */ 48 #define MTK_UART_EFR_HW_FC (MTK_UART_EFR_RTS | MTK_UART_EFR_CTS) 49 #define MTK_UART_DMA_EN_TX 0x2 50 #define MTK_UART_DMA_EN_RX 0x5 51 52 #define MTK_UART_ESCAPE_CHAR 0x77 /* Escape char added under sw fc */ 53 #define MTK_UART_RX_SIZE 0x8000 54 #define MTK_UART_TX_TRIGGER 1 55 #define MTK_UART_RX_TRIGGER MTK_UART_RX_SIZE 56 57 #define MTK_UART_XON1 40 /* I/O: Xon character 1 */ 58 #define MTK_UART_XOFF1 42 /* I/O: Xoff character 1 */ 59 60 #ifdef CONFIG_SERIAL_8250_DMA 61 enum dma_rx_status { 62 DMA_RX_START = 0, 63 DMA_RX_RUNNING = 1, 64 DMA_RX_SHUTDOWN = 2, 65 }; 66 #endif 67 68 struct mtk8250_data { 69 int line; 70 unsigned int rx_pos; 71 unsigned int clk_count; 72 struct clk *uart_clk; 73 struct clk *bus_clk; 74 struct uart_8250_dma *dma; 75 #ifdef CONFIG_SERIAL_8250_DMA 76 enum dma_rx_status rx_status; 77 #endif 78 int rx_wakeup_irq; 79 }; 80 81 /* flow control mode */ 82 enum { 83 MTK_UART_FC_NONE, 84 MTK_UART_FC_SW, 85 MTK_UART_FC_HW, 86 }; 87 88 #ifdef CONFIG_SERIAL_8250_DMA 89 static void mtk8250_rx_dma(struct uart_8250_port *up); 90 91 static void mtk8250_dma_rx_complete(void *param) 92 { 93 struct uart_8250_port *up = param; 94 struct uart_8250_dma *dma = up->dma; 95 struct mtk8250_data *data = up->port.private_data; 96 struct tty_port *tty_port = &up->port.state->port; 97 struct dma_tx_state state; 98 int copied, total, cnt; 99 unsigned char *ptr; 100 unsigned long flags; 101 102 if (data->rx_status == DMA_RX_SHUTDOWN) 103 return; 104 105 uart_port_lock_irqsave(&up->port, &flags); 106 107 dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state); 108 total = dma->rx_size - state.residue; 109 cnt = total; 110 111 if ((data->rx_pos + cnt) > dma->rx_size) 112 cnt = dma->rx_size - data->rx_pos; 113 114 ptr = (unsigned char *)(data->rx_pos + dma->rx_buf); 115 copied = tty_insert_flip_string(tty_port, ptr, cnt); 116 data->rx_pos += cnt; 117 118 if (total > cnt) { 119 ptr = (unsigned char *)(dma->rx_buf); 120 cnt = total - cnt; 121 copied += tty_insert_flip_string(tty_port, ptr, cnt); 122 data->rx_pos = cnt; 123 } 124 125 up->port.icount.rx += copied; 126 127 tty_flip_buffer_push(tty_port); 128 129 mtk8250_rx_dma(up); 130 131 uart_port_unlock_irqrestore(&up->port, flags); 132 } 133 134 static void mtk8250_rx_dma(struct uart_8250_port *up) 135 { 136 struct uart_8250_dma *dma = up->dma; 137 struct dma_async_tx_descriptor *desc; 138 139 desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr, 140 dma->rx_size, DMA_DEV_TO_MEM, 141 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 142 if (!desc) { 143 pr_err("failed to prepare rx slave single\n"); 144 return; 145 } 146 147 desc->callback = mtk8250_dma_rx_complete; 148 desc->callback_param = up; 149 150 dma->rx_cookie = dmaengine_submit(desc); 151 152 dma_async_issue_pending(dma->rxchan); 153 } 154 155 static void mtk8250_dma_enable(struct uart_8250_port *up) 156 { 157 struct uart_8250_dma *dma = up->dma; 158 struct mtk8250_data *data = up->port.private_data; 159 int lcr = serial_in(up, UART_LCR); 160 161 if (data->rx_status != DMA_RX_START) 162 return; 163 164 dma->rxconf.src_port_window_size = dma->rx_size; 165 dma->rxconf.src_addr = dma->rx_addr; 166 167 dma->txconf.dst_port_window_size = UART_XMIT_SIZE; 168 dma->txconf.dst_addr = dma->tx_addr; 169 170 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | 171 UART_FCR_CLEAR_XMIT); 172 serial_out(up, MTK_UART_DMA_EN, 173 MTK_UART_DMA_EN_RX | MTK_UART_DMA_EN_TX); 174 175 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); 176 serial_out(up, MTK_UART_EFR, UART_EFR_ECB); 177 serial_out(up, UART_LCR, lcr); 178 179 if (dmaengine_slave_config(dma->rxchan, &dma->rxconf) != 0) 180 pr_err("failed to configure rx dma channel\n"); 181 if (dmaengine_slave_config(dma->txchan, &dma->txconf) != 0) 182 pr_err("failed to configure tx dma channel\n"); 183 184 data->rx_status = DMA_RX_RUNNING; 185 data->rx_pos = 0; 186 mtk8250_rx_dma(up); 187 } 188 #endif 189 190 static int mtk8250_startup(struct uart_port *port) 191 { 192 #ifdef CONFIG_SERIAL_8250_DMA 193 struct uart_8250_port *up = up_to_u8250p(port); 194 struct mtk8250_data *data = port->private_data; 195 196 /* disable DMA for console */ 197 if (uart_console(port)) 198 up->dma = NULL; 199 200 if (up->dma) { 201 data->rx_status = DMA_RX_START; 202 uart_circ_clear(&port->state->xmit); 203 } 204 #endif 205 memset(&port->icount, 0, sizeof(port->icount)); 206 207 return serial8250_do_startup(port); 208 } 209 210 static void mtk8250_shutdown(struct uart_port *port) 211 { 212 #ifdef CONFIG_SERIAL_8250_DMA 213 struct uart_8250_port *up = up_to_u8250p(port); 214 struct mtk8250_data *data = port->private_data; 215 216 if (up->dma) 217 data->rx_status = DMA_RX_SHUTDOWN; 218 #endif 219 220 return serial8250_do_shutdown(port); 221 } 222 223 static void mtk8250_disable_intrs(struct uart_8250_port *up, int mask) 224 { 225 /* Port locked to synchronize UART_IER access against the console. */ 226 lockdep_assert_held_once(&up->port.lock); 227 228 serial_out(up, UART_IER, serial_in(up, UART_IER) & (~mask)); 229 } 230 231 static void mtk8250_enable_intrs(struct uart_8250_port *up, int mask) 232 { 233 /* Port locked to synchronize UART_IER access against the console. */ 234 lockdep_assert_held_once(&up->port.lock); 235 236 serial_out(up, UART_IER, serial_in(up, UART_IER) | mask); 237 } 238 239 static void mtk8250_set_flow_ctrl(struct uart_8250_port *up, int mode) 240 { 241 struct uart_port *port = &up->port; 242 int lcr = serial_in(up, UART_LCR); 243 244 /* Port locked to synchronize UART_IER access against the console. */ 245 lockdep_assert_held_once(&port->lock); 246 247 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); 248 serial_out(up, MTK_UART_EFR, UART_EFR_ECB); 249 serial_out(up, UART_LCR, lcr); 250 lcr = serial_in(up, UART_LCR); 251 252 switch (mode) { 253 case MTK_UART_FC_NONE: 254 serial_out(up, MTK_UART_ESCAPE_DAT, MTK_UART_ESCAPE_CHAR); 255 serial_out(up, MTK_UART_ESCAPE_EN, 0x00); 256 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); 257 serial_out(up, MTK_UART_EFR, serial_in(up, MTK_UART_EFR) & 258 (~(MTK_UART_EFR_HW_FC | MTK_UART_EFR_SW_FC_MASK))); 259 serial_out(up, UART_LCR, lcr); 260 mtk8250_disable_intrs(up, MTK_UART_IER_XOFFI | 261 MTK_UART_IER_RTSI | MTK_UART_IER_CTSI); 262 break; 263 264 case MTK_UART_FC_HW: 265 serial_out(up, MTK_UART_ESCAPE_DAT, MTK_UART_ESCAPE_CHAR); 266 serial_out(up, MTK_UART_ESCAPE_EN, 0x00); 267 serial_out(up, UART_MCR, UART_MCR_RTS); 268 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); 269 270 /*enable hw flow control*/ 271 serial_out(up, MTK_UART_EFR, MTK_UART_EFR_HW_FC | 272 (serial_in(up, MTK_UART_EFR) & 273 (~(MTK_UART_EFR_HW_FC | MTK_UART_EFR_SW_FC_MASK)))); 274 275 serial_out(up, UART_LCR, lcr); 276 mtk8250_disable_intrs(up, MTK_UART_IER_XOFFI); 277 mtk8250_enable_intrs(up, MTK_UART_IER_CTSI | MTK_UART_IER_RTSI); 278 break; 279 280 case MTK_UART_FC_SW: /*MTK software flow control */ 281 serial_out(up, MTK_UART_ESCAPE_DAT, MTK_UART_ESCAPE_CHAR); 282 serial_out(up, MTK_UART_ESCAPE_EN, 0x01); 283 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); 284 285 /*enable sw flow control */ 286 serial_out(up, MTK_UART_EFR, MTK_UART_EFR_XON1_XOFF1 | 287 (serial_in(up, MTK_UART_EFR) & 288 (~(MTK_UART_EFR_HW_FC | MTK_UART_EFR_SW_FC_MASK)))); 289 290 serial_out(up, MTK_UART_XON1, START_CHAR(port->state->port.tty)); 291 serial_out(up, MTK_UART_XOFF1, STOP_CHAR(port->state->port.tty)); 292 serial_out(up, UART_LCR, lcr); 293 mtk8250_disable_intrs(up, MTK_UART_IER_CTSI|MTK_UART_IER_RTSI); 294 mtk8250_enable_intrs(up, MTK_UART_IER_XOFFI); 295 break; 296 default: 297 break; 298 } 299 } 300 301 static void 302 mtk8250_set_termios(struct uart_port *port, struct ktermios *termios, 303 const struct ktermios *old) 304 { 305 static const unsigned short fraction_L_mapping[] = { 306 0, 1, 0x5, 0x15, 0x55, 0x57, 0x57, 0x77, 0x7F, 0xFF, 0xFF 307 }; 308 static const unsigned short fraction_M_mapping[] = { 309 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 3 310 }; 311 struct uart_8250_port *up = up_to_u8250p(port); 312 unsigned int baud, quot, fraction; 313 unsigned long flags; 314 int mode; 315 316 #ifdef CONFIG_SERIAL_8250_DMA 317 if (up->dma) { 318 if (uart_console(port)) { 319 devm_kfree(up->port.dev, up->dma); 320 up->dma = NULL; 321 } else { 322 mtk8250_dma_enable(up); 323 } 324 } 325 #endif 326 327 /* 328 * Store the requested baud rate before calling the generic 8250 329 * set_termios method. Standard 8250 port expects bauds to be 330 * no higher than (uartclk / 16) so the baud will be clamped if it 331 * gets out of that bound. Mediatek 8250 port supports speed 332 * higher than that, therefore we'll get original baud rate back 333 * after calling the generic set_termios method and recalculate 334 * the speed later in this method. 335 */ 336 baud = tty_termios_baud_rate(termios); 337 338 serial8250_do_set_termios(port, termios, NULL); 339 340 tty_termios_encode_baud_rate(termios, baud, baud); 341 342 /* 343 * Mediatek UARTs use an extra highspeed register (MTK_UART_HIGHS) 344 * 345 * We need to recalcualte the quot register, as the claculation depends 346 * on the vaule in the highspeed register. 347 * 348 * Some baudrates are not supported by the chip, so we use the next 349 * lower rate supported and update termios c_flag. 350 * 351 * If highspeed register is set to 3, we need to specify sample count 352 * and sample point to increase accuracy. If not, we reset the 353 * registers to their default values. 354 */ 355 baud = uart_get_baud_rate(port, termios, old, 356 port->uartclk / 16 / UART_DIV_MAX, 357 port->uartclk); 358 359 if (baud < 115200) { 360 serial_port_out(port, MTK_UART_HIGHS, 0x0); 361 quot = uart_get_divisor(port, baud); 362 } else { 363 serial_port_out(port, MTK_UART_HIGHS, 0x3); 364 quot = DIV_ROUND_UP(port->uartclk, 256 * baud); 365 } 366 367 /* 368 * Ok, we're now changing the port state. Do it with 369 * interrupts disabled. 370 */ 371 uart_port_lock_irqsave(port, &flags); 372 373 /* 374 * Update the per-port timeout. 375 */ 376 uart_update_timeout(port, termios->c_cflag, baud); 377 378 /* set DLAB we have cval saved in up->lcr from the call to the core */ 379 serial_port_out(port, UART_LCR, up->lcr | UART_LCR_DLAB); 380 serial_dl_write(up, quot); 381 382 /* reset DLAB */ 383 serial_port_out(port, UART_LCR, up->lcr); 384 385 if (baud >= 115200) { 386 unsigned int tmp; 387 388 tmp = (port->uartclk / (baud * quot)) - 1; 389 serial_port_out(port, MTK_UART_SAMPLE_COUNT, tmp); 390 serial_port_out(port, MTK_UART_SAMPLE_POINT, 391 (tmp >> 1) - 1); 392 393 /*count fraction to set fractoin register */ 394 fraction = ((port->uartclk * 100) / baud / quot) % 100; 395 fraction = DIV_ROUND_CLOSEST(fraction, 10); 396 serial_port_out(port, MTK_UART_FRACDIV_L, 397 fraction_L_mapping[fraction]); 398 serial_port_out(port, MTK_UART_FRACDIV_M, 399 fraction_M_mapping[fraction]); 400 } else { 401 serial_port_out(port, MTK_UART_SAMPLE_COUNT, 0x00); 402 serial_port_out(port, MTK_UART_SAMPLE_POINT, 0xff); 403 serial_port_out(port, MTK_UART_FRACDIV_L, 0x00); 404 serial_port_out(port, MTK_UART_FRACDIV_M, 0x00); 405 } 406 407 if ((termios->c_cflag & CRTSCTS) && (!(termios->c_iflag & CRTSCTS))) 408 mode = MTK_UART_FC_HW; 409 else if (termios->c_iflag & CRTSCTS) 410 mode = MTK_UART_FC_SW; 411 else 412 mode = MTK_UART_FC_NONE; 413 414 mtk8250_set_flow_ctrl(up, mode); 415 416 if (uart_console(port)) 417 up->port.cons->cflag = termios->c_cflag; 418 419 uart_port_unlock_irqrestore(port, flags); 420 /* Don't rewrite B0 */ 421 if (tty_termios_baud_rate(termios)) 422 tty_termios_encode_baud_rate(termios, baud, baud); 423 } 424 425 static int __maybe_unused mtk8250_runtime_suspend(struct device *dev) 426 { 427 struct mtk8250_data *data = dev_get_drvdata(dev); 428 struct uart_8250_port *up = serial8250_get_port(data->line); 429 430 /* wait until UART in idle status */ 431 while 432 (serial_in(up, MTK_UART_DEBUG0)); 433 434 clk_disable_unprepare(data->bus_clk); 435 436 return 0; 437 } 438 439 static int __maybe_unused mtk8250_runtime_resume(struct device *dev) 440 { 441 struct mtk8250_data *data = dev_get_drvdata(dev); 442 443 clk_prepare_enable(data->bus_clk); 444 445 return 0; 446 } 447 448 static void 449 mtk8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old) 450 { 451 if (!state) 452 pm_runtime_get_sync(port->dev); 453 454 serial8250_do_pm(port, state, old); 455 456 if (state) 457 pm_runtime_put_sync_suspend(port->dev); 458 } 459 460 #ifdef CONFIG_SERIAL_8250_DMA 461 static bool mtk8250_dma_filter(struct dma_chan *chan, void *param) 462 { 463 return false; 464 } 465 #endif 466 467 static int mtk8250_probe_of(struct platform_device *pdev, struct uart_port *p, 468 struct mtk8250_data *data) 469 { 470 #ifdef CONFIG_SERIAL_8250_DMA 471 int dmacnt; 472 #endif 473 474 data->uart_clk = devm_clk_get(&pdev->dev, "baud"); 475 if (IS_ERR(data->uart_clk)) { 476 /* 477 * For compatibility with older device trees try unnamed 478 * clk when no baud clk can be found. 479 */ 480 data->uart_clk = devm_clk_get(&pdev->dev, NULL); 481 if (IS_ERR(data->uart_clk)) { 482 dev_warn(&pdev->dev, "Can't get uart clock\n"); 483 return PTR_ERR(data->uart_clk); 484 } 485 486 return 0; 487 } 488 489 data->bus_clk = devm_clk_get_enabled(&pdev->dev, "bus"); 490 if (IS_ERR(data->bus_clk)) 491 return PTR_ERR(data->bus_clk); 492 493 data->dma = NULL; 494 #ifdef CONFIG_SERIAL_8250_DMA 495 dmacnt = of_property_count_strings(pdev->dev.of_node, "dma-names"); 496 if (dmacnt == 2) { 497 data->dma = devm_kzalloc(&pdev->dev, sizeof(*data->dma), 498 GFP_KERNEL); 499 if (!data->dma) 500 return -ENOMEM; 501 502 data->dma->fn = mtk8250_dma_filter; 503 data->dma->rx_size = MTK_UART_RX_SIZE; 504 data->dma->rxconf.src_maxburst = MTK_UART_RX_TRIGGER; 505 data->dma->txconf.dst_maxburst = MTK_UART_TX_TRIGGER; 506 } 507 #endif 508 509 return 0; 510 } 511 512 static int mtk8250_probe(struct platform_device *pdev) 513 { 514 struct uart_8250_port uart = {}; 515 struct mtk8250_data *data; 516 struct resource *regs; 517 int irq, err; 518 519 irq = platform_get_irq(pdev, 0); 520 if (irq < 0) 521 return irq; 522 523 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); 524 if (!regs) { 525 dev_err(&pdev->dev, "no registers defined\n"); 526 return -EINVAL; 527 } 528 529 uart.port.membase = devm_ioremap(&pdev->dev, regs->start, 530 resource_size(regs)); 531 if (!uart.port.membase) 532 return -ENOMEM; 533 534 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); 535 if (!data) 536 return -ENOMEM; 537 538 data->clk_count = 0; 539 540 if (pdev->dev.of_node) { 541 err = mtk8250_probe_of(pdev, &uart.port, data); 542 if (err) 543 return err; 544 } else 545 return -ENODEV; 546 547 spin_lock_init(&uart.port.lock); 548 uart.port.mapbase = regs->start; 549 uart.port.irq = irq; 550 uart.port.pm = mtk8250_do_pm; 551 uart.port.type = PORT_16550; 552 uart.port.flags = UPF_BOOT_AUTOCONF | UPF_FIXED_PORT; 553 uart.port.dev = &pdev->dev; 554 uart.port.iotype = UPIO_MEM32; 555 uart.port.regshift = 2; 556 uart.port.private_data = data; 557 uart.port.shutdown = mtk8250_shutdown; 558 uart.port.startup = mtk8250_startup; 559 uart.port.set_termios = mtk8250_set_termios; 560 uart.port.uartclk = clk_get_rate(data->uart_clk); 561 #ifdef CONFIG_SERIAL_8250_DMA 562 if (data->dma) 563 uart.dma = data->dma; 564 #endif 565 566 /* Disable Rate Fix function */ 567 writel(0x0, uart.port.membase + 568 (MTK_UART_RATE_FIX << uart.port.regshift)); 569 570 platform_set_drvdata(pdev, data); 571 572 data->line = serial8250_register_8250_port(&uart); 573 if (data->line < 0) 574 return data->line; 575 576 data->rx_wakeup_irq = platform_get_irq_optional(pdev, 1); 577 578 pm_runtime_set_active(&pdev->dev); 579 pm_runtime_enable(&pdev->dev); 580 581 return 0; 582 } 583 584 static void mtk8250_remove(struct platform_device *pdev) 585 { 586 struct mtk8250_data *data = platform_get_drvdata(pdev); 587 588 pm_runtime_get_sync(&pdev->dev); 589 590 serial8250_unregister_port(data->line); 591 592 pm_runtime_disable(&pdev->dev); 593 pm_runtime_put_noidle(&pdev->dev); 594 } 595 596 static int __maybe_unused mtk8250_suspend(struct device *dev) 597 { 598 struct mtk8250_data *data = dev_get_drvdata(dev); 599 int irq = data->rx_wakeup_irq; 600 int err; 601 602 serial8250_suspend_port(data->line); 603 604 pinctrl_pm_select_sleep_state(dev); 605 if (irq >= 0) { 606 err = enable_irq_wake(irq); 607 if (err) { 608 dev_err(dev, 609 "failed to enable irq wake on IRQ %d: %d\n", 610 irq, err); 611 pinctrl_pm_select_default_state(dev); 612 serial8250_resume_port(data->line); 613 return err; 614 } 615 } 616 617 return 0; 618 } 619 620 static int __maybe_unused mtk8250_resume(struct device *dev) 621 { 622 struct mtk8250_data *data = dev_get_drvdata(dev); 623 int irq = data->rx_wakeup_irq; 624 625 if (irq >= 0) 626 disable_irq_wake(irq); 627 pinctrl_pm_select_default_state(dev); 628 629 serial8250_resume_port(data->line); 630 631 return 0; 632 } 633 634 static const struct dev_pm_ops mtk8250_pm_ops = { 635 SET_SYSTEM_SLEEP_PM_OPS(mtk8250_suspend, mtk8250_resume) 636 SET_RUNTIME_PM_OPS(mtk8250_runtime_suspend, mtk8250_runtime_resume, 637 NULL) 638 }; 639 640 static const struct of_device_id mtk8250_of_match[] = { 641 { .compatible = "mediatek,mt6577-uart" }, 642 { /* Sentinel */ } 643 }; 644 MODULE_DEVICE_TABLE(of, mtk8250_of_match); 645 646 static struct platform_driver mtk8250_platform_driver = { 647 .driver = { 648 .name = "mt6577-uart", 649 .pm = &mtk8250_pm_ops, 650 .of_match_table = mtk8250_of_match, 651 }, 652 .probe = mtk8250_probe, 653 .remove_new = mtk8250_remove, 654 }; 655 module_platform_driver(mtk8250_platform_driver); 656 657 #ifdef CONFIG_SERIAL_8250_CONSOLE 658 static int __init early_mtk8250_setup(struct earlycon_device *device, 659 const char *options) 660 { 661 if (!device->port.membase) 662 return -ENODEV; 663 664 device->port.iotype = UPIO_MEM32; 665 device->port.regshift = 2; 666 667 return early_serial8250_setup(device, NULL); 668 } 669 670 OF_EARLYCON_DECLARE(mtk8250, "mediatek,mt6577-uart", early_mtk8250_setup); 671 #endif 672 673 MODULE_AUTHOR("Matthias Brugger"); 674 MODULE_LICENSE("GPL"); 675 MODULE_DESCRIPTION("Mediatek 8250 serial port driver"); 676