1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com> 4 * 5 * Based on msm_serial.c, which is: 6 * Copyright (C) 2007 Google, Inc. 7 * Author: Robert Love <rlove@google.com> 8 */ 9 10 #include <linux/hrtimer.h> 11 #include <linux/delay.h> 12 #include <linux/io.h> 13 #include <linux/ioport.h> 14 #include <linux/irq.h> 15 #include <linux/init.h> 16 #include <linux/console.h> 17 #include <linux/platform_device.h> 18 #include <linux/tty.h> 19 #include <linux/tty_flip.h> 20 #include <linux/serial_core.h> 21 #include <linux/serial.h> 22 #include <linux/slab.h> 23 #include <linux/clk.h> 24 #include <linux/of.h> 25 #include <linux/err.h> 26 27 /* 28 * UART Register offsets 29 */ 30 31 #define VT8500_URTDR 0x0000 /* Transmit data */ 32 #define VT8500_URRDR 0x0004 /* Receive data */ 33 #define VT8500_URDIV 0x0008 /* Clock/Baud rate divisor */ 34 #define VT8500_URLCR 0x000C /* Line control */ 35 #define VT8500_URICR 0x0010 /* IrDA control */ 36 #define VT8500_URIER 0x0014 /* Interrupt enable */ 37 #define VT8500_URISR 0x0018 /* Interrupt status */ 38 #define VT8500_URUSR 0x001c /* UART status */ 39 #define VT8500_URFCR 0x0020 /* FIFO control */ 40 #define VT8500_URFIDX 0x0024 /* FIFO index */ 41 #define VT8500_URBKR 0x0028 /* Break signal count */ 42 #define VT8500_URTOD 0x002c /* Time out divisor */ 43 #define VT8500_TXFIFO 0x1000 /* Transmit FIFO (16x8) */ 44 #define VT8500_RXFIFO 0x1020 /* Receive FIFO (16x10) */ 45 46 /* 47 * Interrupt enable and status bits 48 */ 49 50 #define TXDE (1 << 0) /* Tx Data empty */ 51 #define RXDF (1 << 1) /* Rx Data full */ 52 #define TXFAE (1 << 2) /* Tx FIFO almost empty */ 53 #define TXFE (1 << 3) /* Tx FIFO empty */ 54 #define RXFAF (1 << 4) /* Rx FIFO almost full */ 55 #define RXFF (1 << 5) /* Rx FIFO full */ 56 #define TXUDR (1 << 6) /* Tx underrun */ 57 #define RXOVER (1 << 7) /* Rx overrun */ 58 #define PER (1 << 8) /* Parity error */ 59 #define FER (1 << 9) /* Frame error */ 60 #define TCTS (1 << 10) /* Toggle of CTS */ 61 #define RXTOUT (1 << 11) /* Rx timeout */ 62 #define BKDONE (1 << 12) /* Break signal done */ 63 #define ERR (1 << 13) /* AHB error response */ 64 65 #define RX_FIFO_INTS (RXFAF | RXFF | RXOVER | PER | FER | RXTOUT) 66 #define TX_FIFO_INTS (TXFAE | TXFE | TXUDR) 67 68 /* 69 * Line control bits 70 */ 71 72 #define VT8500_TXEN (1 << 0) /* Enable transmit logic */ 73 #define VT8500_RXEN (1 << 1) /* Enable receive logic */ 74 #define VT8500_CS8 (1 << 2) /* 8-bit data length (vs. 7-bit) */ 75 #define VT8500_CSTOPB (1 << 3) /* 2 stop bits (vs. 1) */ 76 #define VT8500_PARENB (1 << 4) /* Enable parity */ 77 #define VT8500_PARODD (1 << 5) /* Odd parity (vs. even) */ 78 #define VT8500_RTS (1 << 6) /* Ready to send */ 79 #define VT8500_LOOPBK (1 << 7) /* Enable internal loopback */ 80 #define VT8500_DMA (1 << 8) /* Enable DMA mode (needs FIFO) */ 81 #define VT8500_BREAK (1 << 9) /* Initiate break signal */ 82 #define VT8500_PSLVERR (1 << 10) /* APB error upon empty RX FIFO read */ 83 #define VT8500_SWRTSCTS (1 << 11) /* Software-controlled RTS/CTS */ 84 85 /* 86 * Capability flags (driver-internal) 87 */ 88 89 #define VT8500_HAS_SWRTSCTS_SWITCH (1 << 1) 90 91 #define VT8500_RECOMMENDED_CLK 12000000 92 #define VT8500_OVERSAMPLING_DIVISOR 13 93 #define VT8500_MAX_PORTS 6 94 95 struct vt8500_port { 96 struct uart_port uart; 97 char name[16]; 98 struct clk *clk; 99 unsigned int clk_predivisor; 100 unsigned int ier; 101 unsigned int vt8500_uart_flags; 102 }; 103 104 /* 105 * we use this variable to keep track of which ports 106 * have been allocated as we can't use pdev->id in 107 * devicetree 108 */ 109 static DECLARE_BITMAP(vt8500_ports_in_use, VT8500_MAX_PORTS); 110 vt8500_write(struct uart_port * port,unsigned int val,unsigned int off)111 static inline void vt8500_write(struct uart_port *port, unsigned int val, 112 unsigned int off) 113 { 114 writel(val, port->membase + off); 115 } 116 vt8500_read(struct uart_port * port,unsigned int off)117 static inline unsigned int vt8500_read(struct uart_port *port, unsigned int off) 118 { 119 return readl(port->membase + off); 120 } 121 vt8500_stop_tx(struct uart_port * port)122 static void vt8500_stop_tx(struct uart_port *port) 123 { 124 struct vt8500_port *vt8500_port = container_of(port, 125 struct vt8500_port, 126 uart); 127 128 vt8500_port->ier &= ~TX_FIFO_INTS; 129 vt8500_write(port, vt8500_port->ier, VT8500_URIER); 130 } 131 vt8500_stop_rx(struct uart_port * port)132 static void vt8500_stop_rx(struct uart_port *port) 133 { 134 struct vt8500_port *vt8500_port = container_of(port, 135 struct vt8500_port, 136 uart); 137 138 vt8500_port->ier &= ~RX_FIFO_INTS; 139 vt8500_write(port, vt8500_port->ier, VT8500_URIER); 140 } 141 vt8500_enable_ms(struct uart_port * port)142 static void vt8500_enable_ms(struct uart_port *port) 143 { 144 struct vt8500_port *vt8500_port = container_of(port, 145 struct vt8500_port, 146 uart); 147 148 vt8500_port->ier |= TCTS; 149 vt8500_write(port, vt8500_port->ier, VT8500_URIER); 150 } 151 handle_rx(struct uart_port * port)152 static void handle_rx(struct uart_port *port) 153 { 154 struct tty_port *tport = &port->state->port; 155 156 /* 157 * Handle overrun 158 */ 159 if ((vt8500_read(port, VT8500_URISR) & RXOVER)) { 160 port->icount.overrun++; 161 tty_insert_flip_char(tport, 0, TTY_OVERRUN); 162 } 163 164 /* and now the main RX loop */ 165 while (vt8500_read(port, VT8500_URFIDX) & 0x1f00) { 166 unsigned int c; 167 char flag = TTY_NORMAL; 168 169 c = readw(port->membase + VT8500_RXFIFO) & 0x3ff; 170 171 /* Mask conditions we're ignoring. */ 172 c &= ~port->read_status_mask; 173 174 if (c & FER) { 175 port->icount.frame++; 176 flag = TTY_FRAME; 177 } else if (c & PER) { 178 port->icount.parity++; 179 flag = TTY_PARITY; 180 } 181 port->icount.rx++; 182 183 if (!uart_handle_sysrq_char(port, c)) 184 tty_insert_flip_char(tport, c, flag); 185 } 186 187 tty_flip_buffer_push(tport); 188 } 189 vt8500_tx_empty(struct uart_port * port)190 static unsigned int vt8500_tx_empty(struct uart_port *port) 191 { 192 unsigned int idx = vt8500_read(port, VT8500_URFIDX) & 0x1f; 193 194 return idx < 16 ? TIOCSER_TEMT : 0; 195 } 196 handle_tx(struct uart_port * port)197 static void handle_tx(struct uart_port *port) 198 { 199 u8 ch; 200 201 uart_port_tx(port, ch, 202 vt8500_tx_empty(port), 203 writeb(ch, port->membase + VT8500_TXFIFO)); 204 } 205 vt8500_start_tx(struct uart_port * port)206 static void vt8500_start_tx(struct uart_port *port) 207 { 208 struct vt8500_port *vt8500_port = container_of(port, 209 struct vt8500_port, 210 uart); 211 212 vt8500_port->ier &= ~TX_FIFO_INTS; 213 vt8500_write(port, vt8500_port->ier, VT8500_URIER); 214 handle_tx(port); 215 vt8500_port->ier |= TX_FIFO_INTS; 216 vt8500_write(port, vt8500_port->ier, VT8500_URIER); 217 } 218 handle_delta_cts(struct uart_port * port)219 static void handle_delta_cts(struct uart_port *port) 220 { 221 port->icount.cts++; 222 wake_up_interruptible(&port->state->port.delta_msr_wait); 223 } 224 vt8500_irq(int irq,void * dev_id)225 static irqreturn_t vt8500_irq(int irq, void *dev_id) 226 { 227 struct uart_port *port = dev_id; 228 unsigned long isr; 229 230 uart_port_lock(port); 231 isr = vt8500_read(port, VT8500_URISR); 232 233 /* Acknowledge active status bits */ 234 vt8500_write(port, isr, VT8500_URISR); 235 236 if (isr & RX_FIFO_INTS) 237 handle_rx(port); 238 if (isr & TX_FIFO_INTS) 239 handle_tx(port); 240 if (isr & TCTS) 241 handle_delta_cts(port); 242 243 uart_port_unlock(port); 244 245 return IRQ_HANDLED; 246 } 247 vt8500_get_mctrl(struct uart_port * port)248 static unsigned int vt8500_get_mctrl(struct uart_port *port) 249 { 250 unsigned int usr; 251 252 usr = vt8500_read(port, VT8500_URUSR); 253 if (usr & (1 << 4)) 254 return TIOCM_CTS; 255 else 256 return 0; 257 } 258 vt8500_set_mctrl(struct uart_port * port,unsigned int mctrl)259 static void vt8500_set_mctrl(struct uart_port *port, unsigned int mctrl) 260 { 261 unsigned int lcr = vt8500_read(port, VT8500_URLCR); 262 263 if (mctrl & TIOCM_RTS) 264 lcr |= VT8500_RTS; 265 else 266 lcr &= ~VT8500_RTS; 267 268 vt8500_write(port, lcr, VT8500_URLCR); 269 } 270 vt8500_break_ctl(struct uart_port * port,int break_ctl)271 static void vt8500_break_ctl(struct uart_port *port, int break_ctl) 272 { 273 if (break_ctl) 274 vt8500_write(port, 275 vt8500_read(port, VT8500_URLCR) | VT8500_BREAK, 276 VT8500_URLCR); 277 } 278 vt8500_set_baud_rate(struct uart_port * port,unsigned int baud)279 static int vt8500_set_baud_rate(struct uart_port *port, unsigned int baud) 280 { 281 struct vt8500_port *vt8500_port = 282 container_of(port, struct vt8500_port, uart); 283 unsigned long div; 284 unsigned int loops = 1000; 285 286 div = ((vt8500_port->clk_predivisor - 1) & 0xf) << 16; 287 div |= (uart_get_divisor(port, baud) - 1) & 0x3ff; 288 289 /* Effective baud rate */ 290 baud = port->uartclk / 16 / ((div & 0x3ff) + 1); 291 292 while ((vt8500_read(port, VT8500_URUSR) & (1 << 5)) && --loops) 293 cpu_relax(); 294 295 vt8500_write(port, div, VT8500_URDIV); 296 297 /* Break signal timing depends on baud rate, update accordingly */ 298 vt8500_write(port, mult_frac(baud, 4096, 1000000), VT8500_URBKR); 299 300 return baud; 301 } 302 vt8500_startup(struct uart_port * port)303 static int vt8500_startup(struct uart_port *port) 304 { 305 struct vt8500_port *vt8500_port = 306 container_of(port, struct vt8500_port, uart); 307 int ret; 308 309 snprintf(vt8500_port->name, sizeof(vt8500_port->name), 310 "vt8500_serial%d", port->line); 311 312 ret = request_irq(port->irq, vt8500_irq, IRQF_TRIGGER_HIGH, 313 vt8500_port->name, port); 314 if (unlikely(ret)) 315 return ret; 316 317 vt8500_write(port, 0x03, VT8500_URLCR); /* enable TX & RX */ 318 319 return 0; 320 } 321 vt8500_shutdown(struct uart_port * port)322 static void vt8500_shutdown(struct uart_port *port) 323 { 324 struct vt8500_port *vt8500_port = 325 container_of(port, struct vt8500_port, uart); 326 327 vt8500_port->ier = 0; 328 329 /* disable interrupts and FIFOs */ 330 vt8500_write(&vt8500_port->uart, 0, VT8500_URIER); 331 vt8500_write(&vt8500_port->uart, 0x880, VT8500_URFCR); 332 free_irq(port->irq, port); 333 } 334 vt8500_set_termios(struct uart_port * port,struct ktermios * termios,const struct ktermios * old)335 static void vt8500_set_termios(struct uart_port *port, 336 struct ktermios *termios, 337 const struct ktermios *old) 338 { 339 struct vt8500_port *vt8500_port = 340 container_of(port, struct vt8500_port, uart); 341 unsigned long flags; 342 unsigned int baud, lcr; 343 unsigned int loops = 1000; 344 345 uart_port_lock_irqsave(port, &flags); 346 347 /* calculate and set baud rate */ 348 baud = uart_get_baud_rate(port, termios, old, 900, 921600); 349 baud = vt8500_set_baud_rate(port, baud); 350 if (tty_termios_baud_rate(termios)) 351 tty_termios_encode_baud_rate(termios, baud, baud); 352 353 /* calculate parity */ 354 lcr = vt8500_read(&vt8500_port->uart, VT8500_URLCR); 355 lcr &= ~(VT8500_PARENB | VT8500_PARODD); 356 if (termios->c_cflag & PARENB) { 357 lcr |= VT8500_PARENB; 358 termios->c_cflag &= ~CMSPAR; 359 if (termios->c_cflag & PARODD) 360 lcr |= VT8500_PARODD; 361 } 362 363 /* calculate bits per char */ 364 lcr &= ~VT8500_CS8; 365 switch (termios->c_cflag & CSIZE) { 366 case CS7: 367 break; 368 case CS8: 369 default: 370 lcr |= VT8500_CS8; 371 termios->c_cflag &= ~CSIZE; 372 termios->c_cflag |= CS8; 373 break; 374 } 375 376 /* calculate stop bits */ 377 lcr &= ~VT8500_CSTOPB; 378 if (termios->c_cflag & CSTOPB) 379 lcr |= VT8500_CSTOPB; 380 381 lcr &= ~VT8500_SWRTSCTS; 382 if (vt8500_port->vt8500_uart_flags & VT8500_HAS_SWRTSCTS_SWITCH) 383 lcr |= VT8500_SWRTSCTS; 384 385 /* set parity, bits per char, and stop bit */ 386 vt8500_write(&vt8500_port->uart, lcr, VT8500_URLCR); 387 388 /* Configure status bits to ignore based on termio flags. */ 389 port->read_status_mask = 0; 390 if (termios->c_iflag & IGNPAR) 391 port->read_status_mask = FER | PER; 392 393 uart_update_timeout(port, termios->c_cflag, baud); 394 395 /* Reset FIFOs */ 396 vt8500_write(&vt8500_port->uart, 0x88c, VT8500_URFCR); 397 while ((vt8500_read(&vt8500_port->uart, VT8500_URFCR) & 0xc) 398 && --loops) 399 cpu_relax(); 400 401 /* Every possible FIFO-related interrupt */ 402 vt8500_port->ier = RX_FIFO_INTS | TX_FIFO_INTS; 403 404 /* 405 * CTS flow control 406 */ 407 if (UART_ENABLE_MS(&vt8500_port->uart, termios->c_cflag)) 408 vt8500_port->ier |= TCTS; 409 410 vt8500_write(&vt8500_port->uart, 0x881, VT8500_URFCR); 411 vt8500_write(&vt8500_port->uart, vt8500_port->ier, VT8500_URIER); 412 413 uart_port_unlock_irqrestore(port, flags); 414 } 415 vt8500_type(struct uart_port * port)416 static const char *vt8500_type(struct uart_port *port) 417 { 418 struct vt8500_port *vt8500_port = 419 container_of(port, struct vt8500_port, uart); 420 return vt8500_port->name; 421 } 422 vt8500_release_port(struct uart_port * port)423 static void vt8500_release_port(struct uart_port *port) 424 { 425 } 426 vt8500_request_port(struct uart_port * port)427 static int vt8500_request_port(struct uart_port *port) 428 { 429 return 0; 430 } 431 vt8500_config_port(struct uart_port * port,int flags)432 static void vt8500_config_port(struct uart_port *port, int flags) 433 { 434 port->type = PORT_VT8500; 435 } 436 vt8500_verify_port(struct uart_port * port,struct serial_struct * ser)437 static int vt8500_verify_port(struct uart_port *port, 438 struct serial_struct *ser) 439 { 440 if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_VT8500)) 441 return -EINVAL; 442 if (unlikely(port->irq != ser->irq)) 443 return -EINVAL; 444 return 0; 445 } 446 447 static struct vt8500_port *vt8500_uart_ports[VT8500_MAX_PORTS]; 448 static struct uart_driver vt8500_uart_driver; 449 450 #ifdef CONFIG_SERIAL_VT8500_CONSOLE 451 wait_for_xmitr(struct uart_port * port)452 static void wait_for_xmitr(struct uart_port *port) 453 { 454 unsigned int status, tmout = 10000; 455 456 /* Wait up to 10ms for the character(s) to be sent. */ 457 do { 458 status = vt8500_read(port, VT8500_URFIDX); 459 460 if (--tmout == 0) 461 break; 462 udelay(1); 463 } while (status & 0x10); 464 } 465 vt8500_console_putchar(struct uart_port * port,unsigned char c)466 static void vt8500_console_putchar(struct uart_port *port, unsigned char c) 467 { 468 wait_for_xmitr(port); 469 writeb(c, port->membase + VT8500_TXFIFO); 470 } 471 vt8500_console_write(struct console * co,const char * s,unsigned int count)472 static void vt8500_console_write(struct console *co, const char *s, 473 unsigned int count) 474 { 475 struct vt8500_port *vt8500_port = vt8500_uart_ports[co->index]; 476 unsigned long ier; 477 478 BUG_ON(co->index < 0 || co->index >= vt8500_uart_driver.nr); 479 480 ier = vt8500_read(&vt8500_port->uart, VT8500_URIER); 481 vt8500_write(&vt8500_port->uart, VT8500_URIER, 0); 482 483 uart_console_write(&vt8500_port->uart, s, count, 484 vt8500_console_putchar); 485 486 /* 487 * Finally, wait for transmitter to become empty 488 * and switch back to FIFO 489 */ 490 wait_for_xmitr(&vt8500_port->uart); 491 vt8500_write(&vt8500_port->uart, VT8500_URIER, ier); 492 } 493 vt8500_console_setup(struct console * co,char * options)494 static int __init vt8500_console_setup(struct console *co, char *options) 495 { 496 struct vt8500_port *vt8500_port; 497 int baud = 9600; 498 int bits = 8; 499 int parity = 'n'; 500 int flow = 'n'; 501 502 if (unlikely(co->index >= vt8500_uart_driver.nr || co->index < 0)) 503 return -ENXIO; 504 505 vt8500_port = vt8500_uart_ports[co->index]; 506 507 if (!vt8500_port) 508 return -ENODEV; 509 510 if (options) 511 uart_parse_options(options, &baud, &parity, &bits, &flow); 512 513 return uart_set_options(&vt8500_port->uart, 514 co, baud, parity, bits, flow); 515 } 516 517 static struct console vt8500_console = { 518 .name = "ttyWMT", 519 .write = vt8500_console_write, 520 .device = uart_console_device, 521 .setup = vt8500_console_setup, 522 .flags = CON_PRINTBUFFER, 523 .index = -1, 524 .data = &vt8500_uart_driver, 525 }; 526 527 #define VT8500_CONSOLE (&vt8500_console) 528 529 #else 530 #define VT8500_CONSOLE NULL 531 #endif 532 533 #ifdef CONFIG_CONSOLE_POLL vt8500_get_poll_char(struct uart_port * port)534 static int vt8500_get_poll_char(struct uart_port *port) 535 { 536 unsigned int status = vt8500_read(port, VT8500_URFIDX); 537 538 if (!(status & 0x1f00)) 539 return NO_POLL_CHAR; 540 541 return vt8500_read(port, VT8500_RXFIFO) & 0xff; 542 } 543 vt8500_put_poll_char(struct uart_port * port,unsigned char c)544 static void vt8500_put_poll_char(struct uart_port *port, unsigned char c) 545 { 546 unsigned int status, tmout = 10000; 547 548 do { 549 status = vt8500_read(port, VT8500_URFIDX); 550 551 if (--tmout == 0) 552 break; 553 udelay(1); 554 } while (status & 0x10); 555 556 vt8500_write(port, c, VT8500_TXFIFO); 557 } 558 #endif 559 560 static const struct uart_ops vt8500_uart_pops = { 561 .tx_empty = vt8500_tx_empty, 562 .set_mctrl = vt8500_set_mctrl, 563 .get_mctrl = vt8500_get_mctrl, 564 .stop_tx = vt8500_stop_tx, 565 .start_tx = vt8500_start_tx, 566 .stop_rx = vt8500_stop_rx, 567 .enable_ms = vt8500_enable_ms, 568 .break_ctl = vt8500_break_ctl, 569 .startup = vt8500_startup, 570 .shutdown = vt8500_shutdown, 571 .set_termios = vt8500_set_termios, 572 .type = vt8500_type, 573 .release_port = vt8500_release_port, 574 .request_port = vt8500_request_port, 575 .config_port = vt8500_config_port, 576 .verify_port = vt8500_verify_port, 577 #ifdef CONFIG_CONSOLE_POLL 578 .poll_get_char = vt8500_get_poll_char, 579 .poll_put_char = vt8500_put_poll_char, 580 #endif 581 }; 582 583 static struct uart_driver vt8500_uart_driver = { 584 .owner = THIS_MODULE, 585 .driver_name = "vt8500_serial", 586 .dev_name = "ttyWMT", 587 .nr = 6, 588 .cons = VT8500_CONSOLE, 589 }; 590 591 static unsigned int vt8500_flags; /* none required so far */ 592 static unsigned int wm8880_flags = VT8500_HAS_SWRTSCTS_SWITCH; 593 594 static const struct of_device_id wmt_dt_ids[] = { 595 { .compatible = "via,vt8500-uart", .data = &vt8500_flags}, 596 { .compatible = "wm,wm8880-uart", .data = &wm8880_flags}, 597 {} 598 }; 599 vt8500_serial_probe(struct platform_device * pdev)600 static int vt8500_serial_probe(struct platform_device *pdev) 601 { 602 struct vt8500_port *vt8500_port; 603 struct resource *mmres; 604 struct device_node *np = pdev->dev.of_node; 605 const unsigned int *flags; 606 int ret; 607 int port; 608 int irq; 609 610 flags = of_device_get_match_data(&pdev->dev); 611 if (!flags) 612 return -EINVAL; 613 614 irq = platform_get_irq(pdev, 0); 615 if (irq < 0) 616 return irq; 617 618 if (np) { 619 port = of_alias_get_id(np, "serial"); 620 if (port >= VT8500_MAX_PORTS) 621 port = -1; 622 } else { 623 port = -1; 624 } 625 626 if (port < 0) { 627 /* calculate the port id */ 628 port = find_first_zero_bit(vt8500_ports_in_use, 629 VT8500_MAX_PORTS); 630 } 631 632 if (port >= VT8500_MAX_PORTS) 633 return -ENODEV; 634 635 /* reserve the port id */ 636 if (test_and_set_bit(port, vt8500_ports_in_use)) { 637 /* port already in use - shouldn't really happen */ 638 return -EBUSY; 639 } 640 641 vt8500_port = devm_kzalloc(&pdev->dev, sizeof(struct vt8500_port), 642 GFP_KERNEL); 643 if (!vt8500_port) 644 return -ENOMEM; 645 646 vt8500_port->uart.membase = devm_platform_get_and_ioremap_resource(pdev, 0, &mmres); 647 if (IS_ERR(vt8500_port->uart.membase)) 648 return PTR_ERR(vt8500_port->uart.membase); 649 650 vt8500_port->clk = of_clk_get(pdev->dev.of_node, 0); 651 if (IS_ERR(vt8500_port->clk)) { 652 dev_err(&pdev->dev, "failed to get clock\n"); 653 return -EINVAL; 654 } 655 656 ret = clk_prepare_enable(vt8500_port->clk); 657 if (ret) { 658 dev_err(&pdev->dev, "failed to enable clock\n"); 659 return ret; 660 } 661 662 vt8500_port->vt8500_uart_flags = *flags; 663 vt8500_port->clk_predivisor = DIV_ROUND_CLOSEST( 664 clk_get_rate(vt8500_port->clk), 665 VT8500_RECOMMENDED_CLK 666 ); 667 vt8500_port->uart.type = PORT_VT8500; 668 vt8500_port->uart.iotype = UPIO_MEM; 669 vt8500_port->uart.mapbase = mmres->start; 670 vt8500_port->uart.irq = irq; 671 vt8500_port->uart.fifosize = 16; 672 vt8500_port->uart.ops = &vt8500_uart_pops; 673 vt8500_port->uart.line = port; 674 vt8500_port->uart.dev = &pdev->dev; 675 vt8500_port->uart.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF; 676 vt8500_port->uart.has_sysrq = IS_ENABLED(CONFIG_SERIAL_VT8500_CONSOLE); 677 678 /* Serial core uses the magic "16" everywhere - adjust for it */ 679 vt8500_port->uart.uartclk = 16 * clk_get_rate(vt8500_port->clk) / 680 vt8500_port->clk_predivisor / 681 VT8500_OVERSAMPLING_DIVISOR; 682 683 snprintf(vt8500_port->name, sizeof(vt8500_port->name), 684 "VT8500 UART%d", pdev->id); 685 686 vt8500_uart_ports[port] = vt8500_port; 687 688 uart_add_one_port(&vt8500_uart_driver, &vt8500_port->uart); 689 690 platform_set_drvdata(pdev, vt8500_port); 691 692 return 0; 693 } 694 695 static struct platform_driver vt8500_platform_driver = { 696 .probe = vt8500_serial_probe, 697 .driver = { 698 .name = "vt8500_serial", 699 .of_match_table = wmt_dt_ids, 700 .suppress_bind_attrs = true, 701 }, 702 }; 703 vt8500_serial_init(void)704 static int __init vt8500_serial_init(void) 705 { 706 int ret; 707 708 ret = uart_register_driver(&vt8500_uart_driver); 709 if (unlikely(ret)) 710 return ret; 711 712 ret = platform_driver_register(&vt8500_platform_driver); 713 714 if (unlikely(ret)) 715 uart_unregister_driver(&vt8500_uart_driver); 716 717 return ret; 718 } 719 device_initcall(vt8500_serial_init); 720