1 /* 2 * Freescale STMP37XX/STMP378X Application UART driver 3 * 4 * Author: dmitry pervushin <dimka@embeddedalley.com> 5 * 6 * Copyright 2008-2010 Freescale Semiconductor, Inc. 7 * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved. 8 * 9 * The code contained herein is licensed under the GNU General Public 10 * License. You may obtain a copy of the GNU General Public License 11 * Version 2 or later at the following locations: 12 * 13 * http://www.opensource.org/licenses/gpl-license.html 14 * http://www.gnu.org/copyleft/gpl.html 15 */ 16 17 #if defined(CONFIG_SERIAL_MXS_AUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) 18 #define SUPPORT_SYSRQ 19 #endif 20 21 #include <linux/kernel.h> 22 #include <linux/errno.h> 23 #include <linux/init.h> 24 #include <linux/console.h> 25 #include <linux/interrupt.h> 26 #include <linux/module.h> 27 #include <linux/slab.h> 28 #include <linux/wait.h> 29 #include <linux/tty.h> 30 #include <linux/tty_driver.h> 31 #include <linux/tty_flip.h> 32 #include <linux/serial.h> 33 #include <linux/serial_core.h> 34 #include <linux/platform_device.h> 35 #include <linux/device.h> 36 #include <linux/clk.h> 37 #include <linux/delay.h> 38 #include <linux/io.h> 39 #include <linux/of_device.h> 40 #include <linux/dma-mapping.h> 41 #include <linux/dmaengine.h> 42 43 #include <asm/cacheflush.h> 44 45 #include <linux/gpio.h> 46 #include <linux/gpio/consumer.h> 47 #include <linux/err.h> 48 #include <linux/irq.h> 49 #include "serial_mctrl_gpio.h" 50 51 #define MXS_AUART_PORTS 5 52 #define MXS_AUART_FIFO_SIZE 16 53 54 #define AUART_CTRL0 0x00000000 55 #define AUART_CTRL0_SET 0x00000004 56 #define AUART_CTRL0_CLR 0x00000008 57 #define AUART_CTRL0_TOG 0x0000000c 58 #define AUART_CTRL1 0x00000010 59 #define AUART_CTRL1_SET 0x00000014 60 #define AUART_CTRL1_CLR 0x00000018 61 #define AUART_CTRL1_TOG 0x0000001c 62 #define AUART_CTRL2 0x00000020 63 #define AUART_CTRL2_SET 0x00000024 64 #define AUART_CTRL2_CLR 0x00000028 65 #define AUART_CTRL2_TOG 0x0000002c 66 #define AUART_LINECTRL 0x00000030 67 #define AUART_LINECTRL_SET 0x00000034 68 #define AUART_LINECTRL_CLR 0x00000038 69 #define AUART_LINECTRL_TOG 0x0000003c 70 #define AUART_LINECTRL2 0x00000040 71 #define AUART_LINECTRL2_SET 0x00000044 72 #define AUART_LINECTRL2_CLR 0x00000048 73 #define AUART_LINECTRL2_TOG 0x0000004c 74 #define AUART_INTR 0x00000050 75 #define AUART_INTR_SET 0x00000054 76 #define AUART_INTR_CLR 0x00000058 77 #define AUART_INTR_TOG 0x0000005c 78 #define AUART_DATA 0x00000060 79 #define AUART_STAT 0x00000070 80 #define AUART_DEBUG 0x00000080 81 #define AUART_VERSION 0x00000090 82 #define AUART_AUTOBAUD 0x000000a0 83 84 #define AUART_CTRL0_SFTRST (1 << 31) 85 #define AUART_CTRL0_CLKGATE (1 << 30) 86 #define AUART_CTRL0_RXTO_ENABLE (1 << 27) 87 #define AUART_CTRL0_RXTIMEOUT(v) (((v) & 0x7ff) << 16) 88 #define AUART_CTRL0_XFER_COUNT(v) ((v) & 0xffff) 89 90 #define AUART_CTRL1_XFER_COUNT(v) ((v) & 0xffff) 91 92 #define AUART_CTRL2_DMAONERR (1 << 26) 93 #define AUART_CTRL2_TXDMAE (1 << 25) 94 #define AUART_CTRL2_RXDMAE (1 << 24) 95 96 #define AUART_CTRL2_CTSEN (1 << 15) 97 #define AUART_CTRL2_RTSEN (1 << 14) 98 #define AUART_CTRL2_RTS (1 << 11) 99 #define AUART_CTRL2_RXE (1 << 9) 100 #define AUART_CTRL2_TXE (1 << 8) 101 #define AUART_CTRL2_UARTEN (1 << 0) 102 103 #define AUART_LINECTRL_BAUD_DIVINT_SHIFT 16 104 #define AUART_LINECTRL_BAUD_DIVINT_MASK 0xffff0000 105 #define AUART_LINECTRL_BAUD_DIVINT(v) (((v) & 0xffff) << 16) 106 #define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT 8 107 #define AUART_LINECTRL_BAUD_DIVFRAC_MASK 0x00003f00 108 #define AUART_LINECTRL_BAUD_DIVFRAC(v) (((v) & 0x3f) << 8) 109 #define AUART_LINECTRL_WLEN_MASK 0x00000060 110 #define AUART_LINECTRL_WLEN(v) (((v) & 0x3) << 5) 111 #define AUART_LINECTRL_FEN (1 << 4) 112 #define AUART_LINECTRL_STP2 (1 << 3) 113 #define AUART_LINECTRL_EPS (1 << 2) 114 #define AUART_LINECTRL_PEN (1 << 1) 115 #define AUART_LINECTRL_BRK (1 << 0) 116 117 #define AUART_INTR_RTIEN (1 << 22) 118 #define AUART_INTR_TXIEN (1 << 21) 119 #define AUART_INTR_RXIEN (1 << 20) 120 #define AUART_INTR_CTSMIEN (1 << 17) 121 #define AUART_INTR_RTIS (1 << 6) 122 #define AUART_INTR_TXIS (1 << 5) 123 #define AUART_INTR_RXIS (1 << 4) 124 #define AUART_INTR_CTSMIS (1 << 1) 125 126 #define AUART_STAT_BUSY (1 << 29) 127 #define AUART_STAT_CTS (1 << 28) 128 #define AUART_STAT_TXFE (1 << 27) 129 #define AUART_STAT_TXFF (1 << 25) 130 #define AUART_STAT_RXFE (1 << 24) 131 #define AUART_STAT_OERR (1 << 19) 132 #define AUART_STAT_BERR (1 << 18) 133 #define AUART_STAT_PERR (1 << 17) 134 #define AUART_STAT_FERR (1 << 16) 135 #define AUART_STAT_RXCOUNT_MASK 0xffff 136 137 static struct uart_driver auart_driver; 138 139 enum mxs_auart_type { 140 IMX23_AUART, 141 IMX28_AUART, 142 }; 143 144 struct mxs_auart_port { 145 struct uart_port port; 146 147 #define MXS_AUART_DMA_ENABLED 0x2 148 #define MXS_AUART_DMA_TX_SYNC 2 /* bit 2 */ 149 #define MXS_AUART_DMA_RX_READY 3 /* bit 3 */ 150 #define MXS_AUART_RTSCTS 4 /* bit 4 */ 151 unsigned long flags; 152 unsigned int mctrl_prev; 153 enum mxs_auart_type devtype; 154 155 struct clk *clk; 156 struct device *dev; 157 158 /* for DMA */ 159 struct scatterlist tx_sgl; 160 struct dma_chan *tx_dma_chan; 161 void *tx_dma_buf; 162 163 struct scatterlist rx_sgl; 164 struct dma_chan *rx_dma_chan; 165 void *rx_dma_buf; 166 167 struct mctrl_gpios *gpios; 168 int gpio_irq[UART_GPIO_MAX]; 169 bool ms_irq_enabled; 170 }; 171 172 static const struct platform_device_id mxs_auart_devtype[] = { 173 { .name = "mxs-auart-imx23", .driver_data = IMX23_AUART }, 174 { .name = "mxs-auart-imx28", .driver_data = IMX28_AUART }, 175 { /* sentinel */ } 176 }; 177 MODULE_DEVICE_TABLE(platform, mxs_auart_devtype); 178 179 static const struct of_device_id mxs_auart_dt_ids[] = { 180 { 181 .compatible = "fsl,imx28-auart", 182 .data = &mxs_auart_devtype[IMX28_AUART] 183 }, { 184 .compatible = "fsl,imx23-auart", 185 .data = &mxs_auart_devtype[IMX23_AUART] 186 }, { /* sentinel */ } 187 }; 188 MODULE_DEVICE_TABLE(of, mxs_auart_dt_ids); 189 190 static inline int is_imx28_auart(struct mxs_auart_port *s) 191 { 192 return s->devtype == IMX28_AUART; 193 } 194 195 static inline bool auart_dma_enabled(struct mxs_auart_port *s) 196 { 197 return s->flags & MXS_AUART_DMA_ENABLED; 198 } 199 200 static void mxs_auart_stop_tx(struct uart_port *u); 201 202 #define to_auart_port(u) container_of(u, struct mxs_auart_port, port) 203 204 static void mxs_auart_tx_chars(struct mxs_auart_port *s); 205 206 static void dma_tx_callback(void *param) 207 { 208 struct mxs_auart_port *s = param; 209 struct circ_buf *xmit = &s->port.state->xmit; 210 211 dma_unmap_sg(s->dev, &s->tx_sgl, 1, DMA_TO_DEVICE); 212 213 /* clear the bit used to serialize the DMA tx. */ 214 clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); 215 smp_mb__after_atomic(); 216 217 /* wake up the possible processes. */ 218 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) 219 uart_write_wakeup(&s->port); 220 221 mxs_auart_tx_chars(s); 222 } 223 224 static int mxs_auart_dma_tx(struct mxs_auart_port *s, int size) 225 { 226 struct dma_async_tx_descriptor *desc; 227 struct scatterlist *sgl = &s->tx_sgl; 228 struct dma_chan *channel = s->tx_dma_chan; 229 u32 pio; 230 231 /* [1] : send PIO. Note, the first pio word is CTRL1. */ 232 pio = AUART_CTRL1_XFER_COUNT(size); 233 desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)&pio, 234 1, DMA_TRANS_NONE, 0); 235 if (!desc) { 236 dev_err(s->dev, "step 1 error\n"); 237 return -EINVAL; 238 } 239 240 /* [2] : set DMA buffer. */ 241 sg_init_one(sgl, s->tx_dma_buf, size); 242 dma_map_sg(s->dev, sgl, 1, DMA_TO_DEVICE); 243 desc = dmaengine_prep_slave_sg(channel, sgl, 244 1, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 245 if (!desc) { 246 dev_err(s->dev, "step 2 error\n"); 247 return -EINVAL; 248 } 249 250 /* [3] : submit the DMA */ 251 desc->callback = dma_tx_callback; 252 desc->callback_param = s; 253 dmaengine_submit(desc); 254 dma_async_issue_pending(channel); 255 return 0; 256 } 257 258 static void mxs_auart_tx_chars(struct mxs_auart_port *s) 259 { 260 struct circ_buf *xmit = &s->port.state->xmit; 261 262 if (auart_dma_enabled(s)) { 263 u32 i = 0; 264 int size; 265 void *buffer = s->tx_dma_buf; 266 267 if (test_and_set_bit(MXS_AUART_DMA_TX_SYNC, &s->flags)) 268 return; 269 270 while (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) { 271 size = min_t(u32, UART_XMIT_SIZE - i, 272 CIRC_CNT_TO_END(xmit->head, 273 xmit->tail, 274 UART_XMIT_SIZE)); 275 memcpy(buffer + i, xmit->buf + xmit->tail, size); 276 xmit->tail = (xmit->tail + size) & (UART_XMIT_SIZE - 1); 277 278 i += size; 279 if (i >= UART_XMIT_SIZE) 280 break; 281 } 282 283 if (uart_tx_stopped(&s->port)) 284 mxs_auart_stop_tx(&s->port); 285 286 if (i) { 287 mxs_auart_dma_tx(s, i); 288 } else { 289 clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); 290 smp_mb__after_atomic(); 291 } 292 return; 293 } 294 295 296 while (!(readl(s->port.membase + AUART_STAT) & 297 AUART_STAT_TXFF)) { 298 if (s->port.x_char) { 299 s->port.icount.tx++; 300 writel(s->port.x_char, 301 s->port.membase + AUART_DATA); 302 s->port.x_char = 0; 303 continue; 304 } 305 if (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) { 306 s->port.icount.tx++; 307 writel(xmit->buf[xmit->tail], 308 s->port.membase + AUART_DATA); 309 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); 310 } else 311 break; 312 } 313 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) 314 uart_write_wakeup(&s->port); 315 316 if (uart_circ_empty(&(s->port.state->xmit))) 317 writel(AUART_INTR_TXIEN, 318 s->port.membase + AUART_INTR_CLR); 319 else 320 writel(AUART_INTR_TXIEN, 321 s->port.membase + AUART_INTR_SET); 322 323 if (uart_tx_stopped(&s->port)) 324 mxs_auart_stop_tx(&s->port); 325 } 326 327 static void mxs_auart_rx_char(struct mxs_auart_port *s) 328 { 329 int flag; 330 u32 stat; 331 u8 c; 332 333 c = readl(s->port.membase + AUART_DATA); 334 stat = readl(s->port.membase + AUART_STAT); 335 336 flag = TTY_NORMAL; 337 s->port.icount.rx++; 338 339 if (stat & AUART_STAT_BERR) { 340 s->port.icount.brk++; 341 if (uart_handle_break(&s->port)) 342 goto out; 343 } else if (stat & AUART_STAT_PERR) { 344 s->port.icount.parity++; 345 } else if (stat & AUART_STAT_FERR) { 346 s->port.icount.frame++; 347 } 348 349 /* 350 * Mask off conditions which should be ingored. 351 */ 352 stat &= s->port.read_status_mask; 353 354 if (stat & AUART_STAT_BERR) { 355 flag = TTY_BREAK; 356 } else if (stat & AUART_STAT_PERR) 357 flag = TTY_PARITY; 358 else if (stat & AUART_STAT_FERR) 359 flag = TTY_FRAME; 360 361 if (stat & AUART_STAT_OERR) 362 s->port.icount.overrun++; 363 364 if (uart_handle_sysrq_char(&s->port, c)) 365 goto out; 366 367 uart_insert_char(&s->port, stat, AUART_STAT_OERR, c, flag); 368 out: 369 writel(stat, s->port.membase + AUART_STAT); 370 } 371 372 static void mxs_auart_rx_chars(struct mxs_auart_port *s) 373 { 374 u32 stat = 0; 375 376 for (;;) { 377 stat = readl(s->port.membase + AUART_STAT); 378 if (stat & AUART_STAT_RXFE) 379 break; 380 mxs_auart_rx_char(s); 381 } 382 383 writel(stat, s->port.membase + AUART_STAT); 384 tty_flip_buffer_push(&s->port.state->port); 385 } 386 387 static int mxs_auart_request_port(struct uart_port *u) 388 { 389 return 0; 390 } 391 392 static int mxs_auart_verify_port(struct uart_port *u, 393 struct serial_struct *ser) 394 { 395 if (u->type != PORT_UNKNOWN && u->type != PORT_IMX) 396 return -EINVAL; 397 return 0; 398 } 399 400 static void mxs_auart_config_port(struct uart_port *u, int flags) 401 { 402 } 403 404 static const char *mxs_auart_type(struct uart_port *u) 405 { 406 struct mxs_auart_port *s = to_auart_port(u); 407 408 return dev_name(s->dev); 409 } 410 411 static void mxs_auart_release_port(struct uart_port *u) 412 { 413 } 414 415 static void mxs_auart_set_mctrl(struct uart_port *u, unsigned mctrl) 416 { 417 struct mxs_auart_port *s = to_auart_port(u); 418 419 u32 ctrl = readl(u->membase + AUART_CTRL2); 420 421 ctrl &= ~(AUART_CTRL2_RTSEN | AUART_CTRL2_RTS); 422 if (mctrl & TIOCM_RTS) { 423 if (uart_cts_enabled(u)) 424 ctrl |= AUART_CTRL2_RTSEN; 425 else 426 ctrl |= AUART_CTRL2_RTS; 427 } 428 429 writel(ctrl, u->membase + AUART_CTRL2); 430 431 mctrl_gpio_set(s->gpios, mctrl); 432 } 433 434 #define MCTRL_ANY_DELTA (TIOCM_RI | TIOCM_DSR | TIOCM_CD | TIOCM_CTS) 435 static u32 mxs_auart_modem_status(struct mxs_auart_port *s, u32 mctrl) 436 { 437 u32 mctrl_diff; 438 439 mctrl_diff = mctrl ^ s->mctrl_prev; 440 s->mctrl_prev = mctrl; 441 if (mctrl_diff & MCTRL_ANY_DELTA && s->ms_irq_enabled && 442 s->port.state != NULL) { 443 if (mctrl_diff & TIOCM_RI) 444 s->port.icount.rng++; 445 if (mctrl_diff & TIOCM_DSR) 446 s->port.icount.dsr++; 447 if (mctrl_diff & TIOCM_CD) 448 uart_handle_dcd_change(&s->port, mctrl & TIOCM_CD); 449 if (mctrl_diff & TIOCM_CTS) 450 uart_handle_cts_change(&s->port, mctrl & TIOCM_CTS); 451 452 wake_up_interruptible(&s->port.state->port.delta_msr_wait); 453 } 454 return mctrl; 455 } 456 457 static u32 mxs_auart_get_mctrl(struct uart_port *u) 458 { 459 struct mxs_auart_port *s = to_auart_port(u); 460 u32 stat = readl(u->membase + AUART_STAT); 461 u32 mctrl = 0; 462 463 if (stat & AUART_STAT_CTS) 464 mctrl |= TIOCM_CTS; 465 466 return mctrl_gpio_get(s->gpios, &mctrl); 467 } 468 469 /* 470 * Enable modem status interrupts 471 */ 472 static void mxs_auart_enable_ms(struct uart_port *port) 473 { 474 struct mxs_auart_port *s = to_auart_port(port); 475 476 /* 477 * Interrupt should not be enabled twice 478 */ 479 if (s->ms_irq_enabled) 480 return; 481 482 s->ms_irq_enabled = true; 483 484 if (s->gpio_irq[UART_GPIO_CTS] >= 0) 485 enable_irq(s->gpio_irq[UART_GPIO_CTS]); 486 /* TODO: enable AUART_INTR_CTSMIEN otherwise */ 487 488 if (s->gpio_irq[UART_GPIO_DSR] >= 0) 489 enable_irq(s->gpio_irq[UART_GPIO_DSR]); 490 491 if (s->gpio_irq[UART_GPIO_RI] >= 0) 492 enable_irq(s->gpio_irq[UART_GPIO_RI]); 493 494 if (s->gpio_irq[UART_GPIO_DCD] >= 0) 495 enable_irq(s->gpio_irq[UART_GPIO_DCD]); 496 } 497 498 /* 499 * Disable modem status interrupts 500 */ 501 static void mxs_auart_disable_ms(struct uart_port *port) 502 { 503 struct mxs_auart_port *s = to_auart_port(port); 504 505 /* 506 * Interrupt should not be disabled twice 507 */ 508 if (!s->ms_irq_enabled) 509 return; 510 511 s->ms_irq_enabled = false; 512 513 if (s->gpio_irq[UART_GPIO_CTS] >= 0) 514 disable_irq(s->gpio_irq[UART_GPIO_CTS]); 515 /* TODO: disable AUART_INTR_CTSMIEN otherwise */ 516 517 if (s->gpio_irq[UART_GPIO_DSR] >= 0) 518 disable_irq(s->gpio_irq[UART_GPIO_DSR]); 519 520 if (s->gpio_irq[UART_GPIO_RI] >= 0) 521 disable_irq(s->gpio_irq[UART_GPIO_RI]); 522 523 if (s->gpio_irq[UART_GPIO_DCD] >= 0) 524 disable_irq(s->gpio_irq[UART_GPIO_DCD]); 525 } 526 527 static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s); 528 static void dma_rx_callback(void *arg) 529 { 530 struct mxs_auart_port *s = (struct mxs_auart_port *) arg; 531 struct tty_port *port = &s->port.state->port; 532 int count; 533 u32 stat; 534 535 dma_unmap_sg(s->dev, &s->rx_sgl, 1, DMA_FROM_DEVICE); 536 537 stat = readl(s->port.membase + AUART_STAT); 538 stat &= ~(AUART_STAT_OERR | AUART_STAT_BERR | 539 AUART_STAT_PERR | AUART_STAT_FERR); 540 541 count = stat & AUART_STAT_RXCOUNT_MASK; 542 tty_insert_flip_string(port, s->rx_dma_buf, count); 543 544 writel(stat, s->port.membase + AUART_STAT); 545 tty_flip_buffer_push(port); 546 547 /* start the next DMA for RX. */ 548 mxs_auart_dma_prep_rx(s); 549 } 550 551 static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s) 552 { 553 struct dma_async_tx_descriptor *desc; 554 struct scatterlist *sgl = &s->rx_sgl; 555 struct dma_chan *channel = s->rx_dma_chan; 556 u32 pio[1]; 557 558 /* [1] : send PIO */ 559 pio[0] = AUART_CTRL0_RXTO_ENABLE 560 | AUART_CTRL0_RXTIMEOUT(0x80) 561 | AUART_CTRL0_XFER_COUNT(UART_XMIT_SIZE); 562 desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)pio, 563 1, DMA_TRANS_NONE, 0); 564 if (!desc) { 565 dev_err(s->dev, "step 1 error\n"); 566 return -EINVAL; 567 } 568 569 /* [2] : send DMA request */ 570 sg_init_one(sgl, s->rx_dma_buf, UART_XMIT_SIZE); 571 dma_map_sg(s->dev, sgl, 1, DMA_FROM_DEVICE); 572 desc = dmaengine_prep_slave_sg(channel, sgl, 1, DMA_DEV_TO_MEM, 573 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 574 if (!desc) { 575 dev_err(s->dev, "step 2 error\n"); 576 return -1; 577 } 578 579 /* [3] : submit the DMA, but do not issue it. */ 580 desc->callback = dma_rx_callback; 581 desc->callback_param = s; 582 dmaengine_submit(desc); 583 dma_async_issue_pending(channel); 584 return 0; 585 } 586 587 static void mxs_auart_dma_exit_channel(struct mxs_auart_port *s) 588 { 589 if (s->tx_dma_chan) { 590 dma_release_channel(s->tx_dma_chan); 591 s->tx_dma_chan = NULL; 592 } 593 if (s->rx_dma_chan) { 594 dma_release_channel(s->rx_dma_chan); 595 s->rx_dma_chan = NULL; 596 } 597 598 kfree(s->tx_dma_buf); 599 kfree(s->rx_dma_buf); 600 s->tx_dma_buf = NULL; 601 s->rx_dma_buf = NULL; 602 } 603 604 static void mxs_auart_dma_exit(struct mxs_auart_port *s) 605 { 606 607 writel(AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE | AUART_CTRL2_DMAONERR, 608 s->port.membase + AUART_CTRL2_CLR); 609 610 mxs_auart_dma_exit_channel(s); 611 s->flags &= ~MXS_AUART_DMA_ENABLED; 612 clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); 613 clear_bit(MXS_AUART_DMA_RX_READY, &s->flags); 614 } 615 616 static int mxs_auart_dma_init(struct mxs_auart_port *s) 617 { 618 if (auart_dma_enabled(s)) 619 return 0; 620 621 /* init for RX */ 622 s->rx_dma_chan = dma_request_slave_channel(s->dev, "rx"); 623 if (!s->rx_dma_chan) 624 goto err_out; 625 s->rx_dma_buf = kzalloc(UART_XMIT_SIZE, GFP_KERNEL | GFP_DMA); 626 if (!s->rx_dma_buf) 627 goto err_out; 628 629 /* init for TX */ 630 s->tx_dma_chan = dma_request_slave_channel(s->dev, "tx"); 631 if (!s->tx_dma_chan) 632 goto err_out; 633 s->tx_dma_buf = kzalloc(UART_XMIT_SIZE, GFP_KERNEL | GFP_DMA); 634 if (!s->tx_dma_buf) 635 goto err_out; 636 637 /* set the flags */ 638 s->flags |= MXS_AUART_DMA_ENABLED; 639 dev_dbg(s->dev, "enabled the DMA support."); 640 641 /* The DMA buffer is now the FIFO the TTY subsystem can use */ 642 s->port.fifosize = UART_XMIT_SIZE; 643 644 return 0; 645 646 err_out: 647 mxs_auart_dma_exit_channel(s); 648 return -EINVAL; 649 650 } 651 652 #define RTS_AT_AUART() IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(s->gpios, \ 653 UART_GPIO_RTS)) 654 #define CTS_AT_AUART() IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(s->gpios, \ 655 UART_GPIO_CTS)) 656 static void mxs_auart_settermios(struct uart_port *u, 657 struct ktermios *termios, 658 struct ktermios *old) 659 { 660 struct mxs_auart_port *s = to_auart_port(u); 661 u32 bm, ctrl, ctrl2, div; 662 unsigned int cflag, baud; 663 664 cflag = termios->c_cflag; 665 666 ctrl = AUART_LINECTRL_FEN; 667 ctrl2 = readl(u->membase + AUART_CTRL2); 668 669 /* byte size */ 670 switch (cflag & CSIZE) { 671 case CS5: 672 bm = 0; 673 break; 674 case CS6: 675 bm = 1; 676 break; 677 case CS7: 678 bm = 2; 679 break; 680 case CS8: 681 bm = 3; 682 break; 683 default: 684 return; 685 } 686 687 ctrl |= AUART_LINECTRL_WLEN(bm); 688 689 /* parity */ 690 if (cflag & PARENB) { 691 ctrl |= AUART_LINECTRL_PEN; 692 if ((cflag & PARODD) == 0) 693 ctrl |= AUART_LINECTRL_EPS; 694 } 695 696 u->read_status_mask = 0; 697 698 if (termios->c_iflag & INPCK) 699 u->read_status_mask |= AUART_STAT_PERR; 700 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) 701 u->read_status_mask |= AUART_STAT_BERR; 702 703 /* 704 * Characters to ignore 705 */ 706 u->ignore_status_mask = 0; 707 if (termios->c_iflag & IGNPAR) 708 u->ignore_status_mask |= AUART_STAT_PERR; 709 if (termios->c_iflag & IGNBRK) { 710 u->ignore_status_mask |= AUART_STAT_BERR; 711 /* 712 * If we're ignoring parity and break indicators, 713 * ignore overruns too (for real raw support). 714 */ 715 if (termios->c_iflag & IGNPAR) 716 u->ignore_status_mask |= AUART_STAT_OERR; 717 } 718 719 /* 720 * ignore all characters if CREAD is not set 721 */ 722 if (cflag & CREAD) 723 ctrl2 |= AUART_CTRL2_RXE; 724 else 725 ctrl2 &= ~AUART_CTRL2_RXE; 726 727 /* figure out the stop bits requested */ 728 if (cflag & CSTOPB) 729 ctrl |= AUART_LINECTRL_STP2; 730 731 /* figure out the hardware flow control settings */ 732 ctrl2 &= ~(AUART_CTRL2_CTSEN | AUART_CTRL2_RTSEN); 733 if (cflag & CRTSCTS) { 734 /* 735 * The DMA has a bug(see errata:2836) in mx23. 736 * So we can not implement the DMA for auart in mx23, 737 * we can only implement the DMA support for auart 738 * in mx28. 739 */ 740 if (is_imx28_auart(s) 741 && test_bit(MXS_AUART_RTSCTS, &s->flags)) { 742 if (!mxs_auart_dma_init(s)) 743 /* enable DMA tranfer */ 744 ctrl2 |= AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE 745 | AUART_CTRL2_DMAONERR; 746 } 747 /* Even if RTS is GPIO line RTSEN can be enabled because 748 * the pinctrl configuration decides about RTS pin function */ 749 ctrl2 |= AUART_CTRL2_RTSEN; 750 if (CTS_AT_AUART()) 751 ctrl2 |= AUART_CTRL2_CTSEN; 752 } 753 754 /* set baud rate */ 755 baud = uart_get_baud_rate(u, termios, old, 0, u->uartclk); 756 div = u->uartclk * 32 / baud; 757 ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F); 758 ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6); 759 760 writel(ctrl, u->membase + AUART_LINECTRL); 761 writel(ctrl2, u->membase + AUART_CTRL2); 762 763 uart_update_timeout(u, termios->c_cflag, baud); 764 765 /* prepare for the DMA RX. */ 766 if (auart_dma_enabled(s) && 767 !test_and_set_bit(MXS_AUART_DMA_RX_READY, &s->flags)) { 768 if (!mxs_auart_dma_prep_rx(s)) { 769 /* Disable the normal RX interrupt. */ 770 writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN, 771 u->membase + AUART_INTR_CLR); 772 } else { 773 mxs_auart_dma_exit(s); 774 dev_err(s->dev, "We can not start up the DMA.\n"); 775 } 776 } 777 778 /* CTS flow-control and modem-status interrupts */ 779 if (UART_ENABLE_MS(u, termios->c_cflag)) 780 mxs_auart_enable_ms(u); 781 else 782 mxs_auart_disable_ms(u); 783 } 784 785 static void mxs_auart_set_ldisc(struct uart_port *port, 786 struct ktermios *termios) 787 { 788 if (termios->c_line == N_PPS) { 789 port->flags |= UPF_HARDPPS_CD; 790 mxs_auart_enable_ms(port); 791 } else { 792 port->flags &= ~UPF_HARDPPS_CD; 793 } 794 } 795 796 static irqreturn_t mxs_auart_irq_handle(int irq, void *context) 797 { 798 u32 istat; 799 struct mxs_auart_port *s = context; 800 u32 mctrl_temp = s->mctrl_prev; 801 u32 stat = readl(s->port.membase + AUART_STAT); 802 803 istat = readl(s->port.membase + AUART_INTR); 804 805 /* ack irq */ 806 writel(istat & (AUART_INTR_RTIS 807 | AUART_INTR_TXIS 808 | AUART_INTR_RXIS 809 | AUART_INTR_CTSMIS), 810 s->port.membase + AUART_INTR_CLR); 811 812 /* 813 * Dealing with GPIO interrupt 814 */ 815 if (irq == s->gpio_irq[UART_GPIO_CTS] || 816 irq == s->gpio_irq[UART_GPIO_DCD] || 817 irq == s->gpio_irq[UART_GPIO_DSR] || 818 irq == s->gpio_irq[UART_GPIO_RI]) 819 mxs_auart_modem_status(s, 820 mctrl_gpio_get(s->gpios, &mctrl_temp)); 821 822 if (istat & AUART_INTR_CTSMIS) { 823 if (CTS_AT_AUART() && s->ms_irq_enabled) 824 uart_handle_cts_change(&s->port, 825 stat & AUART_STAT_CTS); 826 writel(AUART_INTR_CTSMIS, 827 s->port.membase + AUART_INTR_CLR); 828 istat &= ~AUART_INTR_CTSMIS; 829 } 830 831 if (istat & (AUART_INTR_RTIS | AUART_INTR_RXIS)) { 832 if (!auart_dma_enabled(s)) 833 mxs_auart_rx_chars(s); 834 istat &= ~(AUART_INTR_RTIS | AUART_INTR_RXIS); 835 } 836 837 if (istat & AUART_INTR_TXIS) { 838 mxs_auart_tx_chars(s); 839 istat &= ~AUART_INTR_TXIS; 840 } 841 842 return IRQ_HANDLED; 843 } 844 845 static void mxs_auart_reset(struct uart_port *u) 846 { 847 int i; 848 unsigned int reg; 849 850 writel(AUART_CTRL0_SFTRST, u->membase + AUART_CTRL0_CLR); 851 852 for (i = 0; i < 10000; i++) { 853 reg = readl(u->membase + AUART_CTRL0); 854 if (!(reg & AUART_CTRL0_SFTRST)) 855 break; 856 udelay(3); 857 } 858 writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR); 859 } 860 861 static int mxs_auart_startup(struct uart_port *u) 862 { 863 int ret; 864 struct mxs_auart_port *s = to_auart_port(u); 865 866 ret = clk_prepare_enable(s->clk); 867 if (ret) 868 return ret; 869 870 writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_CLR); 871 872 writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_SET); 873 874 writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN, 875 u->membase + AUART_INTR); 876 877 /* Reset FIFO size (it could have changed if DMA was enabled) */ 878 u->fifosize = MXS_AUART_FIFO_SIZE; 879 880 /* 881 * Enable fifo so all four bytes of a DMA word are written to 882 * output (otherwise, only the LSB is written, ie. 1 in 4 bytes) 883 */ 884 writel(AUART_LINECTRL_FEN, u->membase + AUART_LINECTRL_SET); 885 886 /* get initial status of modem lines */ 887 mctrl_gpio_get(s->gpios, &s->mctrl_prev); 888 889 s->ms_irq_enabled = false; 890 return 0; 891 } 892 893 static void mxs_auart_shutdown(struct uart_port *u) 894 { 895 struct mxs_auart_port *s = to_auart_port(u); 896 897 mxs_auart_disable_ms(u); 898 899 if (auart_dma_enabled(s)) 900 mxs_auart_dma_exit(s); 901 902 writel(AUART_CTRL2_UARTEN, u->membase + AUART_CTRL2_CLR); 903 904 writel(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN, 905 u->membase + AUART_INTR_CLR); 906 907 writel(AUART_CTRL0_CLKGATE, u->membase + AUART_CTRL0_SET); 908 909 clk_disable_unprepare(s->clk); 910 } 911 912 static unsigned int mxs_auart_tx_empty(struct uart_port *u) 913 { 914 if ((readl(u->membase + AUART_STAT) & 915 (AUART_STAT_TXFE | AUART_STAT_BUSY)) == AUART_STAT_TXFE) 916 return TIOCSER_TEMT; 917 918 return 0; 919 } 920 921 static void mxs_auart_start_tx(struct uart_port *u) 922 { 923 struct mxs_auart_port *s = to_auart_port(u); 924 925 /* enable transmitter */ 926 writel(AUART_CTRL2_TXE, u->membase + AUART_CTRL2_SET); 927 928 mxs_auart_tx_chars(s); 929 } 930 931 static void mxs_auart_stop_tx(struct uart_port *u) 932 { 933 writel(AUART_CTRL2_TXE, u->membase + AUART_CTRL2_CLR); 934 } 935 936 static void mxs_auart_stop_rx(struct uart_port *u) 937 { 938 writel(AUART_CTRL2_RXE, u->membase + AUART_CTRL2_CLR); 939 } 940 941 static void mxs_auart_break_ctl(struct uart_port *u, int ctl) 942 { 943 if (ctl) 944 writel(AUART_LINECTRL_BRK, 945 u->membase + AUART_LINECTRL_SET); 946 else 947 writel(AUART_LINECTRL_BRK, 948 u->membase + AUART_LINECTRL_CLR); 949 } 950 951 static struct uart_ops mxs_auart_ops = { 952 .tx_empty = mxs_auart_tx_empty, 953 .start_tx = mxs_auart_start_tx, 954 .stop_tx = mxs_auart_stop_tx, 955 .stop_rx = mxs_auart_stop_rx, 956 .enable_ms = mxs_auart_enable_ms, 957 .break_ctl = mxs_auart_break_ctl, 958 .set_mctrl = mxs_auart_set_mctrl, 959 .get_mctrl = mxs_auart_get_mctrl, 960 .startup = mxs_auart_startup, 961 .shutdown = mxs_auart_shutdown, 962 .set_termios = mxs_auart_settermios, 963 .set_ldisc = mxs_auart_set_ldisc, 964 .type = mxs_auart_type, 965 .release_port = mxs_auart_release_port, 966 .request_port = mxs_auart_request_port, 967 .config_port = mxs_auart_config_port, 968 .verify_port = mxs_auart_verify_port, 969 }; 970 971 static struct mxs_auart_port *auart_port[MXS_AUART_PORTS]; 972 973 #ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE 974 static void mxs_auart_console_putchar(struct uart_port *port, int ch) 975 { 976 unsigned int to = 1000; 977 978 while (readl(port->membase + AUART_STAT) & AUART_STAT_TXFF) { 979 if (!to--) 980 break; 981 udelay(1); 982 } 983 984 writel(ch, port->membase + AUART_DATA); 985 } 986 987 static void 988 auart_console_write(struct console *co, const char *str, unsigned int count) 989 { 990 struct mxs_auart_port *s; 991 struct uart_port *port; 992 unsigned int old_ctrl0, old_ctrl2; 993 unsigned int to = 20000; 994 995 if (co->index >= MXS_AUART_PORTS || co->index < 0) 996 return; 997 998 s = auart_port[co->index]; 999 port = &s->port; 1000 1001 clk_enable(s->clk); 1002 1003 /* First save the CR then disable the interrupts */ 1004 old_ctrl2 = readl(port->membase + AUART_CTRL2); 1005 old_ctrl0 = readl(port->membase + AUART_CTRL0); 1006 1007 writel(AUART_CTRL0_CLKGATE, 1008 port->membase + AUART_CTRL0_CLR); 1009 writel(AUART_CTRL2_UARTEN | AUART_CTRL2_TXE, 1010 port->membase + AUART_CTRL2_SET); 1011 1012 uart_console_write(port, str, count, mxs_auart_console_putchar); 1013 1014 /* Finally, wait for transmitter to become empty ... */ 1015 while (readl(port->membase + AUART_STAT) & AUART_STAT_BUSY) { 1016 udelay(1); 1017 if (!to--) 1018 break; 1019 } 1020 1021 /* 1022 * ... and restore the TCR if we waited long enough for the transmitter 1023 * to be idle. This might keep the transmitter enabled although it is 1024 * unused, but that is better than to disable it while it is still 1025 * transmitting. 1026 */ 1027 if (!(readl(port->membase + AUART_STAT) & AUART_STAT_BUSY)) { 1028 writel(old_ctrl0, port->membase + AUART_CTRL0); 1029 writel(old_ctrl2, port->membase + AUART_CTRL2); 1030 } 1031 1032 clk_disable(s->clk); 1033 } 1034 1035 static void __init 1036 auart_console_get_options(struct uart_port *port, int *baud, 1037 int *parity, int *bits) 1038 { 1039 unsigned int lcr_h, quot; 1040 1041 if (!(readl(port->membase + AUART_CTRL2) & AUART_CTRL2_UARTEN)) 1042 return; 1043 1044 lcr_h = readl(port->membase + AUART_LINECTRL); 1045 1046 *parity = 'n'; 1047 if (lcr_h & AUART_LINECTRL_PEN) { 1048 if (lcr_h & AUART_LINECTRL_EPS) 1049 *parity = 'e'; 1050 else 1051 *parity = 'o'; 1052 } 1053 1054 if ((lcr_h & AUART_LINECTRL_WLEN_MASK) == AUART_LINECTRL_WLEN(2)) 1055 *bits = 7; 1056 else 1057 *bits = 8; 1058 1059 quot = ((readl(port->membase + AUART_LINECTRL) 1060 & AUART_LINECTRL_BAUD_DIVINT_MASK)) 1061 >> (AUART_LINECTRL_BAUD_DIVINT_SHIFT - 6); 1062 quot |= ((readl(port->membase + AUART_LINECTRL) 1063 & AUART_LINECTRL_BAUD_DIVFRAC_MASK)) 1064 >> AUART_LINECTRL_BAUD_DIVFRAC_SHIFT; 1065 if (quot == 0) 1066 quot = 1; 1067 1068 *baud = (port->uartclk << 2) / quot; 1069 } 1070 1071 static int __init 1072 auart_console_setup(struct console *co, char *options) 1073 { 1074 struct mxs_auart_port *s; 1075 int baud = 9600; 1076 int bits = 8; 1077 int parity = 'n'; 1078 int flow = 'n'; 1079 int ret; 1080 1081 /* 1082 * Check whether an invalid uart number has been specified, and 1083 * if so, search for the first available port that does have 1084 * console support. 1085 */ 1086 if (co->index == -1 || co->index >= ARRAY_SIZE(auart_port)) 1087 co->index = 0; 1088 s = auart_port[co->index]; 1089 if (!s) 1090 return -ENODEV; 1091 1092 ret = clk_prepare_enable(s->clk); 1093 if (ret) 1094 return ret; 1095 1096 if (options) 1097 uart_parse_options(options, &baud, &parity, &bits, &flow); 1098 else 1099 auart_console_get_options(&s->port, &baud, &parity, &bits); 1100 1101 ret = uart_set_options(&s->port, co, baud, parity, bits, flow); 1102 1103 clk_disable_unprepare(s->clk); 1104 1105 return ret; 1106 } 1107 1108 static struct console auart_console = { 1109 .name = "ttyAPP", 1110 .write = auart_console_write, 1111 .device = uart_console_device, 1112 .setup = auart_console_setup, 1113 .flags = CON_PRINTBUFFER, 1114 .index = -1, 1115 .data = &auart_driver, 1116 }; 1117 #endif 1118 1119 static struct uart_driver auart_driver = { 1120 .owner = THIS_MODULE, 1121 .driver_name = "ttyAPP", 1122 .dev_name = "ttyAPP", 1123 .major = 0, 1124 .minor = 0, 1125 .nr = MXS_AUART_PORTS, 1126 #ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE 1127 .cons = &auart_console, 1128 #endif 1129 }; 1130 1131 /* 1132 * This function returns 1 if pdev isn't a device instatiated by dt, 0 if it 1133 * could successfully get all information from dt or a negative errno. 1134 */ 1135 static int serial_mxs_probe_dt(struct mxs_auart_port *s, 1136 struct platform_device *pdev) 1137 { 1138 struct device_node *np = pdev->dev.of_node; 1139 int ret; 1140 1141 if (!np) 1142 /* no device tree device */ 1143 return 1; 1144 1145 ret = of_alias_get_id(np, "serial"); 1146 if (ret < 0) { 1147 dev_err(&pdev->dev, "failed to get alias id: %d\n", ret); 1148 return ret; 1149 } 1150 s->port.line = ret; 1151 1152 if (of_get_property(np, "fsl,uart-has-rtscts", NULL)) 1153 set_bit(MXS_AUART_RTSCTS, &s->flags); 1154 1155 return 0; 1156 } 1157 1158 static int mxs_auart_init_gpios(struct mxs_auart_port *s, struct device *dev) 1159 { 1160 enum mctrl_gpio_idx i; 1161 struct gpio_desc *gpiod; 1162 1163 s->gpios = mctrl_gpio_init(dev, 0); 1164 if (IS_ERR(s->gpios)) 1165 return PTR_ERR(s->gpios); 1166 1167 /* Block (enabled before) DMA option if RTS or CTS is GPIO line */ 1168 if (!RTS_AT_AUART() || !CTS_AT_AUART()) { 1169 if (test_bit(MXS_AUART_RTSCTS, &s->flags)) 1170 dev_warn(dev, 1171 "DMA and flow control via gpio may cause some problems. DMA disabled!\n"); 1172 clear_bit(MXS_AUART_RTSCTS, &s->flags); 1173 } 1174 1175 for (i = 0; i < UART_GPIO_MAX; i++) { 1176 gpiod = mctrl_gpio_to_gpiod(s->gpios, i); 1177 if (gpiod && (gpiod_get_direction(gpiod) == GPIOF_DIR_IN)) 1178 s->gpio_irq[i] = gpiod_to_irq(gpiod); 1179 else 1180 s->gpio_irq[i] = -EINVAL; 1181 } 1182 1183 return 0; 1184 } 1185 1186 static void mxs_auart_free_gpio_irq(struct mxs_auart_port *s) 1187 { 1188 enum mctrl_gpio_idx i; 1189 1190 for (i = 0; i < UART_GPIO_MAX; i++) 1191 if (s->gpio_irq[i] >= 0) 1192 free_irq(s->gpio_irq[i], s); 1193 } 1194 1195 static int mxs_auart_request_gpio_irq(struct mxs_auart_port *s) 1196 { 1197 int *irq = s->gpio_irq; 1198 enum mctrl_gpio_idx i; 1199 int err = 0; 1200 1201 for (i = 0; (i < UART_GPIO_MAX) && !err; i++) { 1202 if (irq[i] < 0) 1203 continue; 1204 1205 irq_set_status_flags(irq[i], IRQ_NOAUTOEN); 1206 err = request_irq(irq[i], mxs_auart_irq_handle, 1207 IRQ_TYPE_EDGE_BOTH, dev_name(s->dev), s); 1208 if (err) 1209 dev_err(s->dev, "%s - Can't get %d irq\n", 1210 __func__, irq[i]); 1211 } 1212 1213 /* 1214 * If something went wrong, rollback. 1215 */ 1216 while (err && (--i >= 0)) 1217 if (irq[i] >= 0) 1218 free_irq(irq[i], s); 1219 1220 return err; 1221 } 1222 1223 static int mxs_auart_probe(struct platform_device *pdev) 1224 { 1225 const struct of_device_id *of_id = 1226 of_match_device(mxs_auart_dt_ids, &pdev->dev); 1227 struct mxs_auart_port *s; 1228 u32 version; 1229 int ret, irq; 1230 struct resource *r; 1231 1232 s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL); 1233 if (!s) 1234 return -ENOMEM; 1235 1236 ret = serial_mxs_probe_dt(s, pdev); 1237 if (ret > 0) 1238 s->port.line = pdev->id < 0 ? 0 : pdev->id; 1239 else if (ret < 0) 1240 return ret; 1241 1242 if (of_id) { 1243 pdev->id_entry = of_id->data; 1244 s->devtype = pdev->id_entry->driver_data; 1245 } 1246 1247 s->clk = devm_clk_get(&pdev->dev, NULL); 1248 if (IS_ERR(s->clk)) 1249 return PTR_ERR(s->clk); 1250 1251 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1252 if (!r) 1253 return -ENXIO; 1254 1255 1256 s->port.mapbase = r->start; 1257 s->port.membase = ioremap(r->start, resource_size(r)); 1258 s->port.ops = &mxs_auart_ops; 1259 s->port.iotype = UPIO_MEM; 1260 s->port.fifosize = MXS_AUART_FIFO_SIZE; 1261 s->port.uartclk = clk_get_rate(s->clk); 1262 s->port.type = PORT_IMX; 1263 s->port.dev = s->dev = &pdev->dev; 1264 1265 s->mctrl_prev = 0; 1266 1267 irq = platform_get_irq(pdev, 0); 1268 if (irq < 0) 1269 return irq; 1270 1271 s->port.irq = irq; 1272 ret = devm_request_irq(&pdev->dev, irq, mxs_auart_irq_handle, 0, 1273 dev_name(&pdev->dev), s); 1274 if (ret) 1275 return ret; 1276 1277 platform_set_drvdata(pdev, s); 1278 1279 ret = mxs_auart_init_gpios(s, &pdev->dev); 1280 if (ret) { 1281 dev_err(&pdev->dev, "Failed to initialize GPIOs.\n"); 1282 return ret; 1283 } 1284 1285 /* 1286 * Get the GPIO lines IRQ 1287 */ 1288 ret = mxs_auart_request_gpio_irq(s); 1289 if (ret) 1290 return ret; 1291 1292 auart_port[s->port.line] = s; 1293 1294 mxs_auart_reset(&s->port); 1295 1296 ret = uart_add_one_port(&auart_driver, &s->port); 1297 if (ret) 1298 goto out_free_gpio_irq; 1299 1300 version = readl(s->port.membase + AUART_VERSION); 1301 dev_info(&pdev->dev, "Found APPUART %d.%d.%d\n", 1302 (version >> 24) & 0xff, 1303 (version >> 16) & 0xff, version & 0xffff); 1304 1305 return 0; 1306 1307 out_free_gpio_irq: 1308 mxs_auart_free_gpio_irq(s); 1309 auart_port[pdev->id] = NULL; 1310 return ret; 1311 } 1312 1313 static int mxs_auart_remove(struct platform_device *pdev) 1314 { 1315 struct mxs_auart_port *s = platform_get_drvdata(pdev); 1316 1317 uart_remove_one_port(&auart_driver, &s->port); 1318 auart_port[pdev->id] = NULL; 1319 mxs_auart_free_gpio_irq(s); 1320 1321 return 0; 1322 } 1323 1324 static struct platform_driver mxs_auart_driver = { 1325 .probe = mxs_auart_probe, 1326 .remove = mxs_auart_remove, 1327 .driver = { 1328 .name = "mxs-auart", 1329 .of_match_table = mxs_auart_dt_ids, 1330 }, 1331 }; 1332 1333 static int __init mxs_auart_init(void) 1334 { 1335 int r; 1336 1337 r = uart_register_driver(&auart_driver); 1338 if (r) 1339 goto out; 1340 1341 r = platform_driver_register(&mxs_auart_driver); 1342 if (r) 1343 goto out_err; 1344 1345 return 0; 1346 out_err: 1347 uart_unregister_driver(&auart_driver); 1348 out: 1349 return r; 1350 } 1351 1352 static void __exit mxs_auart_exit(void) 1353 { 1354 platform_driver_unregister(&mxs_auart_driver); 1355 uart_unregister_driver(&auart_driver); 1356 } 1357 1358 module_init(mxs_auart_init); 1359 module_exit(mxs_auart_exit); 1360 MODULE_LICENSE("GPL"); 1361 MODULE_DESCRIPTION("Freescale MXS application uart driver"); 1362 MODULE_ALIAS("platform:mxs-auart"); 1363