1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * MA35D1 serial driver 4 * Copyright (C) 2023 Nuvoton Technology Corp. 5 */ 6 7 #include <linux/bitfield.h> 8 #include <linux/clk.h> 9 #include <linux/delay.h> 10 #include <linux/of.h> 11 #include <linux/of_platform.h> 12 #include <linux/iopoll.h> 13 #include <linux/serial_core.h> 14 #include <linux/slab.h> 15 #include <linux/tty_flip.h> 16 #include <linux/units.h> 17 18 #define MA35_UART_NR 17 19 20 #define MA35_RBR_REG 0x00 21 #define MA35_THR_REG 0x00 22 #define MA35_IER_REG 0x04 23 #define MA35_FCR_REG 0x08 24 #define MA35_LCR_REG 0x0C 25 #define MA35_MCR_REG 0x10 26 #define MA35_MSR_REG 0x14 27 #define MA35_FSR_REG 0x18 28 #define MA35_ISR_REG 0x1C 29 #define MA35_TOR_REG 0x20 30 #define MA35_BAUD_REG 0x24 31 #define MA35_ALTCTL_REG 0x2C 32 #define MA35_FUN_SEL_REG 0x30 33 #define MA35_WKCTL_REG 0x40 34 #define MA35_WKSTS_REG 0x44 35 36 /* MA35_IER_REG - Interrupt Enable Register */ 37 #define MA35_IER_RDA_IEN BIT(0) /* RBR Available Interrupt Enable */ 38 #define MA35_IER_THRE_IEN BIT(1) /* THR Empty Interrupt Enable */ 39 #define MA35_IER_RLS_IEN BIT(2) /* RX Line Status Interrupt Enable */ 40 #define MA35_IER_RTO_IEN BIT(4) /* RX Time-out Interrupt Enable */ 41 #define MA35_IER_BUFERR_IEN BIT(5) /* Buffer Error Interrupt Enable */ 42 #define MA35_IER_TIME_OUT_EN BIT(11) /* RX Buffer Time-out Counter Enable */ 43 #define MA35_IER_AUTO_RTS BIT(12) /* nRTS Auto-flow Control Enable */ 44 #define MA35_IER_AUTO_CTS BIT(13) /* nCTS Auto-flow Control Enable */ 45 46 /* MA35_FCR_REG - FIFO Control Register */ 47 #define MA35_FCR_RFR BIT(1) /* RX Field Software Reset */ 48 #define MA35_FCR_TFR BIT(2) /* TX Field Software Reset */ 49 #define MA35_FCR_RFITL_MASK GENMASK(7, 4) /* RX FIFO Interrupt Trigger Level */ 50 #define MA35_FCR_RFITL_1BYTE FIELD_PREP(MA35_FCR_RFITL_MASK, 0) 51 #define MA35_FCR_RFITL_4BYTES FIELD_PREP(MA35_FCR_RFITL_MASK, 1) 52 #define MA35_FCR_RFITL_8BYTES FIELD_PREP(MA35_FCR_RFITL_MASK, 2) 53 #define MA35_FCR_RFITL_14BYTES FIELD_PREP(MA35_FCR_RFITL_MASK, 3) 54 #define MA35_FCR_RFITL_30BYTES FIELD_PREP(MA35_FCR_RFITL_MASK, 4) 55 #define MA35_FCR_RTSTL_MASK GENMASK(19, 16) /* nRTS Trigger Level */ 56 #define MA35_FCR_RTSTL_1BYTE FIELD_PREP(MA35_FCR_RTSTL_MASK, 0) 57 #define MA35_FCR_RTSTL_4BYTES FIELD_PREP(MA35_FCR_RTSTL_MASK, 1) 58 #define MA35_FCR_RTSTL_8BYTES FIELD_PREP(MA35_FCR_RTSTL_MASK, 2) 59 #define MA35_FCR_RTSTL_14BYTES FIELD_PREP(MA35_FCR_RTSTL_MASK, 3) 60 #define MA35_FCR_RTSTLL_30BYTES FIELD_PREP(MA35_FCR_RTSTL_MASK, 4) 61 62 /* MA35_LCR_REG - Line Control Register */ 63 #define MA35_LCR_NSB BIT(2) /* Number of “STOP Bit” */ 64 #define MA35_LCR_PBE BIT(3) /* Parity Bit Enable */ 65 #define MA35_LCR_EPE BIT(4) /* Even Parity Enable */ 66 #define MA35_LCR_SPE BIT(5) /* Stick Parity Enable */ 67 #define MA35_LCR_BREAK BIT(6) /* Break Control */ 68 #define MA35_LCR_WLS_MASK GENMASK(1, 0) /* Word Length Selection */ 69 #define MA35_LCR_WLS_5BITS FIELD_PREP(MA35_LCR_WLS_MASK, 0) 70 #define MA35_LCR_WLS_6BITS FIELD_PREP(MA35_LCR_WLS_MASK, 1) 71 #define MA35_LCR_WLS_7BITS FIELD_PREP(MA35_LCR_WLS_MASK, 2) 72 #define MA35_LCR_WLS_8BITS FIELD_PREP(MA35_LCR_WLS_MASK, 3) 73 74 /* MA35_MCR_REG - Modem Control Register */ 75 #define MA35_MCR_RTS_CTRL BIT(1) /* nRTS Signal Control */ 76 #define MA35_MCR_RTSACTLV BIT(9) /* nRTS Pin Active Level */ 77 #define MA35_MCR_RTSSTS BIT(13) /* nRTS Pin Status (Read Only) */ 78 79 /* MA35_MSR_REG - Modem Status Register */ 80 #define MA35_MSR_CTSDETF BIT(0) /* Detect nCTS State Change Flag */ 81 #define MA35_MSR_CTSSTS BIT(4) /* nCTS Pin Status (Read Only) */ 82 #define MA35_MSR_CTSACTLV BIT(8) /* nCTS Pin Active Level */ 83 84 /* MA35_FSR_REG - FIFO Status Register */ 85 #define MA35_FSR_RX_OVER_IF BIT(0) /* RX Overflow Error Interrupt Flag */ 86 #define MA35_FSR_PEF BIT(4) /* Parity Error Flag*/ 87 #define MA35_FSR_FEF BIT(5) /* Framing Error Flag */ 88 #define MA35_FSR_BIF BIT(6) /* Break Interrupt Flag */ 89 #define MA35_FSR_RX_EMPTY BIT(14) /* Receiver FIFO Empty (Read Only) */ 90 #define MA35_FSR_RX_FULL BIT(15) /* Receiver FIFO Full (Read Only) */ 91 #define MA35_FSR_TX_EMPTY BIT(22) /* Transmitter FIFO Empty (Read Only) */ 92 #define MA35_FSR_TX_FULL BIT(23) /* Transmitter FIFO Full (Read Only) */ 93 #define MA35_FSR_TX_OVER_IF BIT(24) /* TX Overflow Error Interrupt Flag */ 94 #define MA35_FSR_TE_FLAG BIT(28) /* Transmitter Empty Flag (Read Only) */ 95 #define MA35_FSR_RXPTR_MSK GENMASK(13, 8) /* TX FIFO Pointer mask */ 96 #define MA35_FSR_TXPTR_MSK GENMASK(21, 16) /* RX FIFO Pointer mask */ 97 98 /* MA35_ISR_REG - Interrupt Status Register */ 99 #define MA35_ISR_RDA_IF BIT(0) /* RBR Available Interrupt Flag */ 100 #define MA35_ISR_THRE_IF BIT(1) /* THR Empty Interrupt Flag */ 101 #define MA35_ISR_RLSIF BIT(2) /* Receive Line Interrupt Flag */ 102 #define MA35_ISR_MODEMIF BIT(3) /* MODEM Interrupt Flag */ 103 #define MA35_ISR_RXTO_IF BIT(4) /* RX Time-out Interrupt Flag */ 104 #define MA35_ISR_BUFEIF BIT(5) /* Buffer Error Interrupt Flag */ 105 #define MA35_ISR_WK_IF BIT(6) /* UART Wake-up Interrupt Flag */ 106 #define MA35_ISR_RDAINT BIT(8) /* RBR Available Interrupt Indicator */ 107 #define MA35_ISR_THRE_INT BIT(9) /* THR Empty Interrupt Indicator */ 108 #define MA35_ISR_ALL 0xFFFFFFFF 109 110 /* MA35_BAUD_REG - Baud Rate Divider Register */ 111 #define MA35_BAUD_MODE_MASK GENMASK(29, 28) 112 #define MA35_BAUD_MODE0 FIELD_PREP(MA35_BAUD_MODE_MASK, 0) 113 #define MA35_BAUD_MODE1 FIELD_PREP(MA35_BAUD_MODE_MASK, 2) 114 #define MA35_BAUD_MODE2 FIELD_PREP(MA35_BAUD_MODE_MASK, 3) 115 #define MA35_BAUD_MASK GENMASK(15, 0) 116 117 /* MA35_ALTCTL_REG - Alternate Control/Status Register */ 118 #define MA35_ALTCTL_RS485AUD BIT(10) /* RS-485 Auto Direction Function */ 119 120 /* MA35_FUN_SEL_REG - Function Select Register */ 121 #define MA35_FUN_SEL_MASK GENMASK(2, 0) 122 #define MA35_FUN_SEL_UART FIELD_PREP(MA35_FUN_SEL_MASK, 0) 123 #define MA35_FUN_SEL_RS485 FIELD_PREP(MA35_FUN_SEL_MASK, 3) 124 125 /* The constrain for MA35D1 UART baud rate divider */ 126 #define MA35_BAUD_DIV_MAX 0xFFFF 127 #define MA35_BAUD_DIV_MIN 11 128 129 /* UART FIFO depth */ 130 #define MA35_UART_FIFO_DEPTH 32 131 /* UART console clock */ 132 #define MA35_UART_CONSOLE_CLK (24 * HZ_PER_MHZ) 133 /* UART register ioremap size */ 134 #define MA35_UART_REG_SIZE 0x100 135 /* Rx Timeout */ 136 #define MA35_UART_RX_TOUT 0x40 137 138 #define MA35_IER_CONFIG (MA35_IER_RTO_IEN | MA35_IER_RDA_IEN | \ 139 MA35_IER_TIME_OUT_EN | MA35_IER_BUFERR_IEN) 140 141 #define MA35_ISR_IF_CHECK (MA35_ISR_RDA_IF | MA35_ISR_RXTO_IF | \ 142 MA35_ISR_THRE_INT | MA35_ISR_BUFEIF) 143 144 #define MA35_FSR_TX_BOTH_EMPTY (MA35_FSR_TE_FLAG | MA35_FSR_TX_EMPTY) 145 146 static struct uart_driver ma35d1serial_reg; 147 148 struct uart_ma35d1_port { 149 struct uart_port port; 150 struct clk *clk; 151 u16 capabilities; /* port capabilities */ 152 u8 ier; 153 u8 lcr; 154 u8 mcr; 155 u32 baud_rate; 156 u32 console_baud_rate; 157 u32 console_line; 158 u32 console_int; 159 }; 160 161 static struct uart_ma35d1_port ma35d1serial_ports[MA35_UART_NR]; 162 163 static struct uart_ma35d1_port *to_ma35d1_uart_port(struct uart_port *uart) 164 { 165 return container_of(uart, struct uart_ma35d1_port, port); 166 } 167 168 static u32 serial_in(struct uart_ma35d1_port *p, u32 offset) 169 { 170 return readl_relaxed(p->port.membase + offset); 171 } 172 173 static void serial_out(struct uart_ma35d1_port *p, u32 offset, u32 value) 174 { 175 writel_relaxed(value, p->port.membase + offset); 176 } 177 178 static void __stop_tx(struct uart_ma35d1_port *p) 179 { 180 u32 ier; 181 182 ier = serial_in(p, MA35_IER_REG); 183 if (ier & MA35_IER_THRE_IEN) 184 serial_out(p, MA35_IER_REG, ier & ~MA35_IER_THRE_IEN); 185 } 186 187 static void ma35d1serial_stop_tx(struct uart_port *port) 188 { 189 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 190 191 __stop_tx(up); 192 } 193 194 static void transmit_chars(struct uart_ma35d1_port *up) 195 { 196 u32 count; 197 u8 ch; 198 199 if (uart_tx_stopped(&up->port)) { 200 ma35d1serial_stop_tx(&up->port); 201 return; 202 } 203 count = MA35_UART_FIFO_DEPTH - FIELD_GET(MA35_FSR_TXPTR_MSK, 204 serial_in(up, MA35_FSR_REG)); 205 uart_port_tx_limited(&up->port, ch, count, 206 !(serial_in(up, MA35_FSR_REG) & MA35_FSR_TX_FULL), 207 serial_out(up, MA35_THR_REG, ch), 208 ({})); 209 } 210 211 static void ma35d1serial_start_tx(struct uart_port *port) 212 { 213 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 214 u32 ier; 215 216 ier = serial_in(up, MA35_IER_REG); 217 serial_out(up, MA35_IER_REG, ier & ~MA35_IER_THRE_IEN); 218 transmit_chars(up); 219 serial_out(up, MA35_IER_REG, ier | MA35_IER_THRE_IEN); 220 } 221 222 static void ma35d1serial_stop_rx(struct uart_port *port) 223 { 224 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 225 u32 ier; 226 227 ier = serial_in(up, MA35_IER_REG); 228 ier &= ~MA35_IER_RDA_IEN; 229 serial_out(up, MA35_IER_REG, ier); 230 } 231 232 static void receive_chars(struct uart_ma35d1_port *up) 233 { 234 int max_count = 256; 235 u8 ch, flag; 236 u32 fsr; 237 238 fsr = serial_in(up, MA35_FSR_REG); 239 do { 240 flag = TTY_NORMAL; 241 up->port.icount.rx++; 242 243 if (unlikely(fsr & (MA35_FSR_BIF | MA35_FSR_FEF | 244 MA35_FSR_PEF | MA35_FSR_RX_OVER_IF))) { 245 if (fsr & MA35_FSR_BIF) { 246 up->port.icount.brk++; 247 if (uart_handle_break(&up->port)) 248 continue; 249 } 250 if (fsr & MA35_FSR_FEF) 251 up->port.icount.frame++; 252 if (fsr & MA35_FSR_PEF) 253 up->port.icount.parity++; 254 if (fsr & MA35_FSR_RX_OVER_IF) 255 up->port.icount.overrun++; 256 257 serial_out(up, MA35_FSR_REG, 258 fsr & (MA35_FSR_BIF | MA35_FSR_FEF | 259 MA35_FSR_PEF | MA35_FSR_RX_OVER_IF)); 260 if (fsr & MA35_FSR_BIF) 261 flag = TTY_BREAK; 262 else if (fsr & MA35_FSR_PEF) 263 flag = TTY_PARITY; 264 else if (fsr & MA35_FSR_FEF) 265 flag = TTY_FRAME; 266 } 267 268 ch = serial_in(up, MA35_RBR_REG); 269 if (uart_handle_sysrq_char(&up->port, ch)) 270 continue; 271 272 spin_lock(&up->port.lock); 273 uart_insert_char(&up->port, fsr, MA35_FSR_RX_OVER_IF, ch, flag); 274 spin_unlock(&up->port.lock); 275 276 fsr = serial_in(up, MA35_FSR_REG); 277 } while (!(fsr & MA35_FSR_RX_EMPTY) && (max_count-- > 0)); 278 279 spin_lock(&up->port.lock); 280 tty_flip_buffer_push(&up->port.state->port); 281 spin_unlock(&up->port.lock); 282 } 283 284 static irqreturn_t ma35d1serial_interrupt(int irq, void *dev_id) 285 { 286 struct uart_port *port = dev_id; 287 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 288 u32 isr, fsr; 289 290 isr = serial_in(up, MA35_ISR_REG); 291 fsr = serial_in(up, MA35_FSR_REG); 292 293 if (!(isr & MA35_ISR_IF_CHECK)) 294 return IRQ_NONE; 295 296 if (isr & (MA35_ISR_RDA_IF | MA35_ISR_RXTO_IF)) 297 receive_chars(up); 298 if (isr & MA35_ISR_THRE_INT) 299 transmit_chars(up); 300 if (fsr & MA35_FSR_TX_OVER_IF) 301 serial_out(up, MA35_FSR_REG, MA35_FSR_TX_OVER_IF); 302 303 return IRQ_HANDLED; 304 } 305 306 static u32 ma35d1serial_tx_empty(struct uart_port *port) 307 { 308 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 309 u32 fsr; 310 311 fsr = serial_in(up, MA35_FSR_REG); 312 if ((fsr & MA35_FSR_TX_BOTH_EMPTY) == MA35_FSR_TX_BOTH_EMPTY) 313 return TIOCSER_TEMT; 314 else 315 return 0; 316 } 317 318 static u32 ma35d1serial_get_mctrl(struct uart_port *port) 319 { 320 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 321 u32 status; 322 u32 ret = 0; 323 324 status = serial_in(up, MA35_MSR_REG); 325 if (!(status & MA35_MSR_CTSSTS)) 326 ret |= TIOCM_CTS; 327 return ret; 328 } 329 330 static void ma35d1serial_set_mctrl(struct uart_port *port, u32 mctrl) 331 { 332 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 333 u32 mcr, msr, ier; 334 335 mcr = serial_in(up, MA35_MCR_REG); 336 mcr &= ~MA35_MCR_RTS_CTRL; 337 338 if (mctrl & TIOCM_RTS) 339 mcr |= MA35_MCR_RTSACTLV; 340 else 341 mcr &= ~MA35_MCR_RTSACTLV; 342 343 if (up->mcr & UART_MCR_AFE) { 344 ier = serial_in(up, MA35_IER_REG); 345 ier |= MA35_IER_AUTO_RTS | MA35_IER_AUTO_CTS; 346 serial_out(up, MA35_IER_REG, ier); 347 up->port.flags |= UPF_HARD_FLOW; 348 } else { 349 ier = serial_in(up, MA35_IER_REG); 350 ier &= ~(MA35_IER_AUTO_RTS | MA35_IER_AUTO_CTS); 351 serial_out(up, MA35_IER_REG, ier); 352 up->port.flags &= ~UPF_HARD_FLOW; 353 } 354 355 msr = serial_in(up, MA35_MSR_REG); 356 msr |= MA35_MSR_CTSACTLV; 357 serial_out(up, MA35_MSR_REG, msr); 358 serial_out(up, MA35_MCR_REG, mcr); 359 } 360 361 static void ma35d1serial_break_ctl(struct uart_port *port, int break_state) 362 { 363 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 364 unsigned long flags; 365 u32 lcr; 366 367 spin_lock_irqsave(&up->port.lock, flags); 368 lcr = serial_in(up, MA35_LCR_REG); 369 if (break_state != 0) 370 lcr |= MA35_LCR_BREAK; 371 else 372 lcr &= ~MA35_LCR_BREAK; 373 serial_out(up, MA35_LCR_REG, lcr); 374 spin_unlock_irqrestore(&up->port.lock, flags); 375 } 376 377 static int ma35d1serial_startup(struct uart_port *port) 378 { 379 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 380 u32 fcr; 381 int retval; 382 383 /* Reset FIFO */ 384 serial_out(up, MA35_FCR_REG, MA35_FCR_TFR | MA35_FCR_RFR); 385 386 /* Clear pending interrupts */ 387 serial_out(up, MA35_ISR_REG, MA35_ISR_ALL); 388 389 retval = request_irq(port->irq, ma35d1serial_interrupt, 0, 390 dev_name(port->dev), port); 391 if (retval) { 392 dev_err(up->port.dev, "request irq failed.\n"); 393 return retval; 394 } 395 396 fcr = serial_in(up, MA35_FCR_REG); 397 fcr |= MA35_FCR_RFITL_4BYTES | MA35_FCR_RTSTL_8BYTES; 398 serial_out(up, MA35_FCR_REG, fcr); 399 serial_out(up, MA35_LCR_REG, MA35_LCR_WLS_8BITS); 400 serial_out(up, MA35_TOR_REG, MA35_UART_RX_TOUT); 401 serial_out(up, MA35_IER_REG, MA35_IER_CONFIG); 402 return 0; 403 } 404 405 static void ma35d1serial_shutdown(struct uart_port *port) 406 { 407 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 408 409 serial_out(up, MA35_IER_REG, 0); 410 free_irq(port->irq, port); 411 } 412 413 static void ma35d1serial_set_termios(struct uart_port *port, 414 struct ktermios *termios, 415 const struct ktermios *old) 416 { 417 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 418 unsigned long flags; 419 u32 baud, quot; 420 u32 lcr = 0; 421 422 lcr = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag)); 423 424 if (termios->c_cflag & CSTOPB) 425 lcr |= MA35_LCR_NSB; 426 if (termios->c_cflag & PARENB) 427 lcr |= MA35_LCR_PBE; 428 if (!(termios->c_cflag & PARODD)) 429 lcr |= MA35_LCR_EPE; 430 if (termios->c_cflag & CMSPAR) 431 lcr |= MA35_LCR_SPE; 432 433 baud = uart_get_baud_rate(port, termios, old, 434 port->uartclk / MA35_BAUD_DIV_MAX, 435 port->uartclk / MA35_BAUD_DIV_MIN); 436 437 /* MA35D1 UART baud rate equation: baudrate = UART_CLK / (quot + 2) */ 438 quot = (port->uartclk / baud) - 2; 439 440 /* 441 * Ok, we're now changing the port state. Do it with 442 * interrupts disabled. 443 */ 444 spin_lock_irqsave(&up->port.lock, flags); 445 446 up->port.read_status_mask = MA35_FSR_RX_OVER_IF; 447 if (termios->c_iflag & INPCK) 448 up->port.read_status_mask |= MA35_FSR_FEF | MA35_FSR_PEF; 449 if (termios->c_iflag & (BRKINT | PARMRK)) 450 up->port.read_status_mask |= MA35_FSR_BIF; 451 452 /* Characteres to ignore */ 453 up->port.ignore_status_mask = 0; 454 if (termios->c_iflag & IGNPAR) 455 up->port.ignore_status_mask |= MA35_FSR_FEF | MA35_FSR_PEF; 456 if (termios->c_iflag & IGNBRK) { 457 up->port.ignore_status_mask |= MA35_FSR_BIF; 458 /* 459 * If we're ignoring parity and break indicators, 460 * ignore overruns too (for real raw support). 461 */ 462 if (termios->c_iflag & IGNPAR) 463 up->port.ignore_status_mask |= MA35_FSR_RX_OVER_IF; 464 } 465 if (termios->c_cflag & CRTSCTS) 466 up->mcr |= UART_MCR_AFE; 467 else 468 up->mcr &= ~UART_MCR_AFE; 469 470 uart_update_timeout(port, termios->c_cflag, baud); 471 472 ma35d1serial_set_mctrl(&up->port, up->port.mctrl); 473 474 serial_out(up, MA35_BAUD_REG, MA35_BAUD_MODE2 | FIELD_PREP(MA35_BAUD_MASK, quot)); 475 476 serial_out(up, MA35_LCR_REG, lcr); 477 478 spin_unlock_irqrestore(&up->port.lock, flags); 479 } 480 481 static const char *ma35d1serial_type(struct uart_port *port) 482 { 483 return "ma35d1-uart"; 484 } 485 486 static void ma35d1serial_config_port(struct uart_port *port, int flags) 487 { 488 /* 489 * Driver core for serial ports forces a non-zero value for port type. 490 * Write an arbitrary value here to accommodate the serial core driver, 491 * as ID part of UAPI is redundant. 492 */ 493 port->type = 1; 494 } 495 496 static int ma35d1serial_verify_port(struct uart_port *port, struct serial_struct *ser) 497 { 498 if (port->type != PORT_UNKNOWN && ser->type != 1) 499 return -EINVAL; 500 501 return 0; 502 } 503 504 static const struct uart_ops ma35d1serial_ops = { 505 .tx_empty = ma35d1serial_tx_empty, 506 .set_mctrl = ma35d1serial_set_mctrl, 507 .get_mctrl = ma35d1serial_get_mctrl, 508 .stop_tx = ma35d1serial_stop_tx, 509 .start_tx = ma35d1serial_start_tx, 510 .stop_rx = ma35d1serial_stop_rx, 511 .break_ctl = ma35d1serial_break_ctl, 512 .startup = ma35d1serial_startup, 513 .shutdown = ma35d1serial_shutdown, 514 .set_termios = ma35d1serial_set_termios, 515 .type = ma35d1serial_type, 516 .config_port = ma35d1serial_config_port, 517 .verify_port = ma35d1serial_verify_port, 518 }; 519 520 static const struct of_device_id ma35d1_serial_of_match[] = { 521 { .compatible = "nuvoton,ma35d1-uart" }, 522 {}, 523 }; 524 MODULE_DEVICE_TABLE(of, ma35d1_serial_of_match); 525 526 #ifdef CONFIG_SERIAL_NUVOTON_MA35D1_CONSOLE 527 528 static struct device_node *ma35d1serial_uart_nodes[MA35_UART_NR]; 529 530 static void wait_for_xmitr(struct uart_ma35d1_port *up) 531 { 532 unsigned int reg = 0; 533 534 read_poll_timeout_atomic(serial_in, reg, reg & MA35_FSR_TX_EMPTY, 535 1, 10000, false, 536 up, MA35_FSR_REG); 537 } 538 539 static void ma35d1serial_console_putchar(struct uart_port *port, unsigned char ch) 540 { 541 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 542 543 wait_for_xmitr(up); 544 serial_out(up, MA35_THR_REG, ch); 545 } 546 547 /* 548 * Print a string to the serial port trying not to disturb 549 * any possible real use of the port... 550 * 551 * The console_lock must be held when we get here. 552 */ 553 static void ma35d1serial_console_write(struct console *co, const char *s, u32 count) 554 { 555 struct uart_ma35d1_port *up = &ma35d1serial_ports[co->index]; 556 unsigned long flags; 557 int locked = 1; 558 u32 ier; 559 560 if (up->port.sysrq) 561 locked = 0; 562 else if (oops_in_progress) 563 locked = spin_trylock_irqsave(&up->port.lock, flags); 564 else 565 spin_lock_irqsave(&up->port.lock, flags); 566 567 /* 568 * First save the IER then disable the interrupts 569 */ 570 ier = serial_in(up, MA35_IER_REG); 571 serial_out(up, MA35_IER_REG, 0); 572 573 uart_console_write(&up->port, s, count, ma35d1serial_console_putchar); 574 575 wait_for_xmitr(up); 576 serial_out(up, MA35_IER_REG, ier); 577 578 if (locked) 579 spin_unlock_irqrestore(&up->port.lock, flags); 580 } 581 582 static int __init ma35d1serial_console_setup(struct console *co, char *options) 583 { 584 struct device_node *np; 585 struct uart_ma35d1_port *p; 586 u32 val32[4]; 587 struct uart_port *port; 588 int baud = 115200; 589 int bits = 8; 590 int parity = 'n'; 591 int flow = 'n'; 592 593 if ((co->index < 0) || (co->index >= MA35_UART_NR)) { 594 pr_debug("Console Port%x out of range\n", co->index); 595 return -EINVAL; 596 } 597 598 np = ma35d1serial_uart_nodes[co->index]; 599 p = &ma35d1serial_ports[co->index]; 600 if (!np || !p) 601 return -ENODEV; 602 603 if (of_property_read_u32_array(np, "reg", val32, ARRAY_SIZE(val32)) != 0) 604 return -EINVAL; 605 606 p->port.iobase = val32[1]; 607 p->port.membase = ioremap(p->port.iobase, MA35_UART_REG_SIZE); 608 if (!p->port.membase) 609 return -ENOMEM; 610 611 p->port.ops = &ma35d1serial_ops; 612 p->port.line = 0; 613 p->port.uartclk = MA35_UART_CONSOLE_CLK; 614 615 port = &ma35d1serial_ports[co->index].port; 616 617 if (options) 618 uart_parse_options(options, &baud, &parity, &bits, &flow); 619 620 return uart_set_options(port, co, baud, parity, bits, flow); 621 } 622 623 static struct console ma35d1serial_console = { 624 .name = "ttyNVT", 625 .write = ma35d1serial_console_write, 626 .device = uart_console_device, 627 .setup = ma35d1serial_console_setup, 628 .flags = CON_PRINTBUFFER | CON_ENABLED, 629 .index = -1, 630 .data = &ma35d1serial_reg, 631 }; 632 633 static void ma35d1serial_console_init_port(void) 634 { 635 u32 i = 0; 636 struct device_node *np; 637 638 for_each_matching_node(np, ma35d1_serial_of_match) { 639 if (ma35d1serial_uart_nodes[i] == NULL) { 640 of_node_get(np); 641 ma35d1serial_uart_nodes[i] = np; 642 i++; 643 if (i == MA35_UART_NR) 644 break; 645 } 646 } 647 } 648 649 static int __init ma35d1serial_console_init(void) 650 { 651 ma35d1serial_console_init_port(); 652 register_console(&ma35d1serial_console); 653 return 0; 654 } 655 console_initcall(ma35d1serial_console_init); 656 657 #define MA35D1SERIAL_CONSOLE (&ma35d1serial_console) 658 #else 659 #define MA35D1SERIAL_CONSOLE NULL 660 #endif 661 662 static struct uart_driver ma35d1serial_reg = { 663 .owner = THIS_MODULE, 664 .driver_name = "serial", 665 .dev_name = "ttyNVT", 666 .major = TTY_MAJOR, 667 .minor = 64, 668 .cons = MA35D1SERIAL_CONSOLE, 669 .nr = MA35_UART_NR, 670 }; 671 672 /* 673 * Register a set of serial devices attached to a platform device. 674 * The list is terminated with a zero flags entry, which means we expect 675 * all entries to have at least UPF_BOOT_AUTOCONF set. 676 */ 677 static int ma35d1serial_probe(struct platform_device *pdev) 678 { 679 struct resource *res_mem; 680 struct uart_ma35d1_port *up; 681 int ret = 0; 682 683 if (pdev->dev.of_node) { 684 ret = of_alias_get_id(pdev->dev.of_node, "serial"); 685 if (ret < 0) { 686 dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n", ret); 687 return ret; 688 } 689 } 690 up = &ma35d1serial_ports[ret]; 691 up->port.line = ret; 692 res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 693 if (!res_mem) 694 return -ENODEV; 695 696 up->port.iobase = res_mem->start; 697 up->port.membase = ioremap(up->port.iobase, MA35_UART_REG_SIZE); 698 up->port.ops = &ma35d1serial_ops; 699 700 spin_lock_init(&up->port.lock); 701 702 up->clk = of_clk_get(pdev->dev.of_node, 0); 703 if (IS_ERR(up->clk)) { 704 ret = PTR_ERR(up->clk); 705 dev_err(&pdev->dev, "failed to get core clk: %d\n", ret); 706 goto err_iounmap; 707 } 708 709 ret = clk_prepare_enable(up->clk); 710 if (ret) 711 goto err_iounmap; 712 713 if (up->port.line != 0) 714 up->port.uartclk = clk_get_rate(up->clk); 715 716 ret = platform_get_irq(pdev, 0); 717 if (ret < 0) 718 goto err_clk_disable; 719 720 up->port.irq = ret; 721 up->port.dev = &pdev->dev; 722 up->port.flags = UPF_BOOT_AUTOCONF; 723 724 platform_set_drvdata(pdev, up); 725 726 ret = uart_add_one_port(&ma35d1serial_reg, &up->port); 727 if (ret < 0) 728 goto err_free_irq; 729 730 return 0; 731 732 err_free_irq: 733 free_irq(up->port.irq, &up->port); 734 735 err_clk_disable: 736 clk_disable_unprepare(up->clk); 737 738 err_iounmap: 739 iounmap(up->port.membase); 740 return ret; 741 } 742 743 /* 744 * Remove serial ports registered against a platform device. 745 */ 746 static int ma35d1serial_remove(struct platform_device *dev) 747 { 748 struct uart_port *port = platform_get_drvdata(dev); 749 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 750 751 uart_remove_one_port(&ma35d1serial_reg, port); 752 clk_disable_unprepare(up->clk); 753 return 0; 754 } 755 756 static int ma35d1serial_suspend(struct platform_device *dev, pm_message_t state) 757 { 758 struct uart_port *port = platform_get_drvdata(dev); 759 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 760 761 uart_suspend_port(&ma35d1serial_reg, &up->port); 762 if (up->port.line == 0) { 763 up->console_baud_rate = serial_in(up, MA35_BAUD_REG); 764 up->console_line = serial_in(up, MA35_LCR_REG); 765 up->console_int = serial_in(up, MA35_IER_REG); 766 } 767 return 0; 768 } 769 770 static int ma35d1serial_resume(struct platform_device *dev) 771 { 772 struct uart_port *port = platform_get_drvdata(dev); 773 struct uart_ma35d1_port *up = to_ma35d1_uart_port(port); 774 775 if (up->port.line == 0) { 776 serial_out(up, MA35_BAUD_REG, up->console_baud_rate); 777 serial_out(up, MA35_LCR_REG, up->console_line); 778 serial_out(up, MA35_IER_REG, up->console_int); 779 } 780 uart_resume_port(&ma35d1serial_reg, &up->port); 781 return 0; 782 } 783 784 static struct platform_driver ma35d1serial_driver = { 785 .probe = ma35d1serial_probe, 786 .remove = ma35d1serial_remove, 787 .suspend = ma35d1serial_suspend, 788 .resume = ma35d1serial_resume, 789 .driver = { 790 .name = "ma35d1-uart", 791 .owner = THIS_MODULE, 792 .of_match_table = of_match_ptr(ma35d1_serial_of_match), 793 }, 794 }; 795 796 static int __init ma35d1serial_init(void) 797 { 798 int ret; 799 800 ret = uart_register_driver(&ma35d1serial_reg); 801 if (ret) 802 return ret; 803 804 ret = platform_driver_register(&ma35d1serial_driver); 805 if (ret) 806 uart_unregister_driver(&ma35d1serial_reg); 807 808 return ret; 809 } 810 811 static void __exit ma35d1serial_exit(void) 812 { 813 platform_driver_unregister(&ma35d1serial_driver); 814 uart_unregister_driver(&ma35d1serial_reg); 815 } 816 817 module_init(ma35d1serial_init); 818 module_exit(ma35d1serial_exit); 819 820 MODULE_LICENSE("GPL"); 821 MODULE_DESCRIPTION("MA35D1 serial driver"); 822