drivers/tty/serial/fsl_lpuart.c

   1 /*
   2  *  Freescale lpuart serial port driver
   3  *
   4  *  Copyright 2012-2014 Freescale Semiconductor, Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #if defined(CONFIG_SERIAL_FSL_LPUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  13 #define SUPPORT_SYSRQ
  14 #endif
  15
  16 #include <linux/clk.h>
  17 #include <linux/console.h>
  18 #include <linux/dma-mapping.h>
  19 #include <linux/dmaengine.h>
  20 #include <linux/dmapool.h>
  21 #include <linux/io.h>
  22 #include <linux/irq.h>
  23 #include <linux/module.h>
  24 #include <linux/of.h>
  25 #include <linux/of_device.h>
  26 #include <linux/of_dma.h>
  27 #include <linux/serial_core.h>
  28 #include <linux/slab.h>
  29 #include <linux/tty_flip.h>
  30
  31 /* All registers are 8-bit width */
  32 #define UARTBDH                 0x00
  33 #define UARTBDL                 0x01
  34 #define UARTCR1                 0x02
  35 #define UARTCR2                 0x03
  36 #define UARTSR1                 0x04
  37 #define UARTCR3                 0x06
  38 #define UARTDR                  0x07
  39 #define UARTCR4                 0x0a
  40 #define UARTCR5                 0x0b
  41 #define UARTMODEM               0x0d
  42 #define UARTPFIFO               0x10
  43 #define UARTCFIFO               0x11
  44 #define UARTSFIFO               0x12
  45 #define UARTTWFIFO              0x13
  46 #define UARTTCFIFO              0x14
  47 #define UARTRWFIFO              0x15
  48
  49 #define UARTBDH_LBKDIE          0x80
  50 #define UARTBDH_RXEDGIE         0x40
  51 #define UARTBDH_SBR_MASK        0x1f
  52
  53 #define UARTCR1_LOOPS           0x80
  54 #define UARTCR1_RSRC            0x20
  55 #define UARTCR1_M               0x10
  56 #define UARTCR1_WAKE            0x08
  57 #define UARTCR1_ILT             0x04
  58 #define UARTCR1_PE              0x02
  59 #define UARTCR1_PT              0x01
  60
  61 #define UARTCR2_TIE             0x80
  62 #define UARTCR2_TCIE            0x40
  63 #define UARTCR2_RIE             0x20
  64 #define UARTCR2_ILIE            0x10
  65 #define UARTCR2_TE              0x08
  66 #define UARTCR2_RE              0x04
  67 #define UARTCR2_RWU             0x02
  68 #define UARTCR2_SBK             0x01
  69
  70 #define UARTSR1_TDRE            0x80
  71 #define UARTSR1_TC              0x40
  72 #define UARTSR1_RDRF            0x20
  73 #define UARTSR1_IDLE            0x10
  74 #define UARTSR1_OR              0x08
  75 #define UARTSR1_NF              0x04
  76 #define UARTSR1_FE              0x02
  77 #define UARTSR1_PE              0x01
  78
  79 #define UARTCR3_R8              0x80
  80 #define UARTCR3_T8              0x40
  81 #define UARTCR3_TXDIR           0x20
  82 #define UARTCR3_TXINV           0x10
  83 #define UARTCR3_ORIE            0x08
  84 #define UARTCR3_NEIE            0x04
  85 #define UARTCR3_FEIE            0x02
  86 #define UARTCR3_PEIE            0x01
  87
  88 #define UARTCR4_MAEN1           0x80
  89 #define UARTCR4_MAEN2           0x40
  90 #define UARTCR4_M10             0x20
  91 #define UARTCR4_BRFA_MASK       0x1f
  92 #define UARTCR4_BRFA_OFF        0
  93
  94 #define UARTCR5_TDMAS           0x80
  95 #define UARTCR5_RDMAS           0x20
  96
  97 #define UARTMODEM_RXRTSE        0x08
  98 #define UARTMODEM_TXRTSPOL      0x04
  99 #define UARTMODEM_TXRTSE        0x02
 100 #define UARTMODEM_TXCTSE        0x01
 101
 102 #define UARTPFIFO_TXFE          0x80
 103 #define UARTPFIFO_FIFOSIZE_MASK 0x7
 104 #define UARTPFIFO_TXSIZE_OFF    4
 105 #define UARTPFIFO_RXFE          0x08
 106 #define UARTPFIFO_RXSIZE_OFF    0
 107
 108 #define UARTCFIFO_TXFLUSH       0x80
 109 #define UARTCFIFO_RXFLUSH       0x40
 110 #define UARTCFIFO_RXOFE         0x04
 111 #define UARTCFIFO_TXOFE         0x02
 112 #define UARTCFIFO_RXUFE         0x01
 113
 114 #define UARTSFIFO_TXEMPT        0x80
 115 #define UARTSFIFO_RXEMPT        0x40
 116 #define UARTSFIFO_RXOF          0x04
 117 #define UARTSFIFO_TXOF          0x02
 118 #define UARTSFIFO_RXUF          0x01
 119
 120 /* 32-bit register definition */
 121 #define UARTBAUD                0x00
 122 #define UARTSTAT                0x04
 123 #define UARTCTRL                0x08
 124 #define UARTDATA                0x0C
 125 #define UARTMATCH               0x10
 126 #define UARTMODIR               0x14
 127 #define UARTFIFO                0x18
 128 #define UARTWATER               0x1c
 129
 130 #define UARTBAUD_MAEN1          0x80000000
 131 #define UARTBAUD_MAEN2          0x40000000
 132 #define UARTBAUD_M10            0x20000000
 133 #define UARTBAUD_TDMAE          0x00800000
 134 #define UARTBAUD_RDMAE          0x00200000
 135 #define UARTBAUD_MATCFG         0x00400000
 136 #define UARTBAUD_BOTHEDGE       0x00020000
 137 #define UARTBAUD_RESYNCDIS      0x00010000
 138 #define UARTBAUD_LBKDIE         0x00008000
 139 #define UARTBAUD_RXEDGIE        0x00004000
 140 #define UARTBAUD_SBNS           0x00002000
 141 #define UARTBAUD_SBR            0x00000000
 142 #define UARTBAUD_SBR_MASK       0x1fff
 143 #define UARTBAUD_OSR_MASK       0x1f
 144 #define UARTBAUD_OSR_SHIFT      24
 145
 146 #define UARTSTAT_LBKDIF         0x80000000
 147 #define UARTSTAT_RXEDGIF        0x40000000
 148 #define UARTSTAT_MSBF           0x20000000
 149 #define UARTSTAT_RXINV          0x10000000
 150 #define UARTSTAT_RWUID          0x08000000
 151 #define UARTSTAT_BRK13          0x04000000
 152 #define UARTSTAT_LBKDE          0x02000000
 153 #define UARTSTAT_RAF            0x01000000
 154 #define UARTSTAT_TDRE           0x00800000
 155 #define UARTSTAT_TC             0x00400000
 156 #define UARTSTAT_RDRF           0x00200000
 157 #define UARTSTAT_IDLE           0x00100000
 158 #define UARTSTAT_OR             0x00080000
 159 #define UARTSTAT_NF             0x00040000
 160 #define UARTSTAT_FE             0x00020000
 161 #define UARTSTAT_PE             0x00010000
 162 #define UARTSTAT_MA1F           0x00008000
 163 #define UARTSTAT_M21F           0x00004000
 164
 165 #define UARTCTRL_R8T9           0x80000000
 166 #define UARTCTRL_R9T8           0x40000000
 167 #define UARTCTRL_TXDIR          0x20000000
 168 #define UARTCTRL_TXINV          0x10000000
 169 #define UARTCTRL_ORIE           0x08000000
 170 #define UARTCTRL_NEIE           0x04000000
 171 #define UARTCTRL_FEIE           0x02000000
 172 #define UARTCTRL_PEIE           0x01000000
 173 #define UARTCTRL_TIE            0x00800000
 174 #define UARTCTRL_TCIE           0x00400000
 175 #define UARTCTRL_RIE            0x00200000
 176 #define UARTCTRL_ILIE           0x00100000
 177 #define UARTCTRL_TE             0x00080000
 178 #define UARTCTRL_RE             0x00040000
 179 #define UARTCTRL_RWU            0x00020000
 180 #define UARTCTRL_SBK            0x00010000
 181 #define UARTCTRL_MA1IE          0x00008000
 182 #define UARTCTRL_MA2IE          0x00004000
 183 #define UARTCTRL_IDLECFG        0x00000100
 184 #define UARTCTRL_LOOPS          0x00000080
 185 #define UARTCTRL_DOZEEN         0x00000040
 186 #define UARTCTRL_RSRC           0x00000020
 187 #define UARTCTRL_M              0x00000010
 188 #define UARTCTRL_WAKE           0x00000008
 189 #define UARTCTRL_ILT            0x00000004
 190 #define UARTCTRL_PE             0x00000002
 191 #define UARTCTRL_PT             0x00000001
 192
 193 #define UARTDATA_NOISY          0x00008000
 194 #define UARTDATA_PARITYE        0x00004000
 195 #define UARTDATA_FRETSC         0x00002000
 196 #define UARTDATA_RXEMPT         0x00001000
 197 #define UARTDATA_IDLINE         0x00000800
 198 #define UARTDATA_MASK           0x3ff
 199
 200 #define UARTMODIR_IREN          0x00020000
 201 #define UARTMODIR_TXCTSSRC      0x00000020
 202 #define UARTMODIR_TXCTSC        0x00000010
 203 #define UARTMODIR_RXRTSE        0x00000008
 204 #define UARTMODIR_TXRTSPOL      0x00000004
 205 #define UARTMODIR_TXRTSE        0x00000002
 206 #define UARTMODIR_TXCTSE        0x00000001
 207
 208 #define UARTFIFO_TXEMPT         0x00800000
 209 #define UARTFIFO_RXEMPT         0x00400000
 210 #define UARTFIFO_TXOF           0x00020000
 211 #define UARTFIFO_RXUF           0x00010000
 212 #define UARTFIFO_TXFLUSH        0x00008000
 213 #define UARTFIFO_RXFLUSH        0x00004000
 214 #define UARTFIFO_TXOFE          0x00000200
 215 #define UARTFIFO_RXUFE          0x00000100
 216 #define UARTFIFO_TXFE           0x00000080
 217 #define UARTFIFO_FIFOSIZE_MASK  0x7
 218 #define UARTFIFO_TXSIZE_OFF     4
 219 #define UARTFIFO_RXFE           0x00000008
 220 #define UARTFIFO_RXSIZE_OFF     0
 221
 222 #define UARTWATER_COUNT_MASK    0xff
 223 #define UARTWATER_TXCNT_OFF     8
 224 #define UARTWATER_RXCNT_OFF     24
 225 #define UARTWATER_WATER_MASK    0xff
 226 #define UARTWATER_TXWATER_OFF   0
 227 #define UARTWATER_RXWATER_OFF   16
 228
 229 /* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */
 230 #define DMA_RX_TIMEOUT          (10)
 231
 232 #define DRIVER_NAME     "fsl-lpuart"
 233 #define DEV_NAME        "ttyLP"
 234 #define UART_NR         6
 235
 236 /* IMX lpuart has four extra unused regs located at the beginning */
 237 #define IMX_REG_OFF     0x10
 238
 239 struct lpuart_port {
 240         struct uart_port        port;
 241         struct clk              *clk;
 242         unsigned int            txfifo_size;
 243         unsigned int            rxfifo_size;
 244
 245         bool                    lpuart_dma_tx_use;
 246         bool                    lpuart_dma_rx_use;
 247         struct dma_chan         *dma_tx_chan;
 248         struct dma_chan         *dma_rx_chan;
 249         struct dma_async_tx_descriptor  *dma_tx_desc;
 250         struct dma_async_tx_descriptor  *dma_rx_desc;
 251         dma_cookie_t            dma_tx_cookie;
 252         dma_cookie_t            dma_rx_cookie;
 253         unsigned int            dma_tx_bytes;
 254         unsigned int            dma_rx_bytes;
 255         bool                    dma_tx_in_progress;
 256         unsigned int            dma_rx_timeout;
 257         struct timer_list       lpuart_timer;
 258         struct scatterlist      rx_sgl, tx_sgl[2];
 259         struct circ_buf         rx_ring;
 260         int                     rx_dma_rng_buf_len;
 261         unsigned int            dma_tx_nents;
 262         wait_queue_head_t       dma_wait;
 263 };
 264
 265 struct lpuart_soc_data {
 266         char    iotype;
 267         u8      reg_off;
 268 };
 269
 270 static const struct lpuart_soc_data vf_data = {
 271         .iotype = UPIO_MEM,
 272 };
 273
 274 static const struct lpuart_soc_data ls_data = {
 275         .iotype = UPIO_MEM32BE,
 276 };
 277
 278 static struct lpuart_soc_data imx_data = {
 279         .iotype = UPIO_MEM32,
 280         .reg_off = IMX_REG_OFF,
 281 };
 282
 283 static const struct of_device_id lpuart_dt_ids[] = {
 284         { .compatible = "fsl,vf610-lpuart",     .data = &vf_data, },
 285         { .compatible = "fsl,ls1021a-lpuart",   .data = &ls_data, },
 286         { .compatible = "fsl,imx7ulp-lpuart",   .data = &imx_data, },
 287         { /* sentinel */ }
 288 };
 289 MODULE_DEVICE_TABLE(of, lpuart_dt_ids);
 290
 291 /* Forward declare this for the dma callbacks*/
 292 static void lpuart_dma_tx_complete(void *arg);
 293
 294 static inline u32 lpuart32_read(struct uart_port *port, u32 off)
 295 {
 296         switch (port->iotype) {
 297         case UPIO_MEM32:
 298                 return readl(port->membase + off);
 299         case UPIO_MEM32BE:
 300                 return ioread32be(port->membase + off);
 301         default:
 302                 return 0;
 303         }
 304 }
 305
 306 static inline void lpuart32_write(struct uart_port *port, u32 val,
 307                                   u32 off)
 308 {
 309         switch (port->iotype) {
 310         case UPIO_MEM32:
 311                 writel(val, port->membase + off);
 312                 break;
 313         case UPIO_MEM32BE:
 314                 iowrite32be(val, port->membase + off);
 315                 break;
 316         }
 317 }
 318
 319 static void lpuart_stop_tx(struct uart_port *port)
 320 {
 321         unsigned char temp;
 322
 323         temp = readb(port->membase + UARTCR2);
 324         temp &= ~(UARTCR2_TIE | UARTCR2_TCIE);
 325         writeb(temp, port->membase + UARTCR2);
 326 }
 327
 328 static void lpuart32_stop_tx(struct uart_port *port)
 329 {
 330         unsigned long temp;
 331
 332         temp = lpuart32_read(port, UARTCTRL);
 333         temp &= ~(UARTCTRL_TIE | UARTCTRL_TCIE);
 334         lpuart32_write(port, temp, UARTCTRL);
 335 }
 336
 337 static void lpuart_stop_rx(struct uart_port *port)
 338 {
 339         unsigned char temp;
 340
 341         temp = readb(port->membase + UARTCR2);
 342         writeb(temp & ~UARTCR2_RE, port->membase + UARTCR2);
 343 }
 344
 345 static void lpuart32_stop_rx(struct uart_port *port)
 346 {
 347         unsigned long temp;
 348
 349         temp = lpuart32_read(port, UARTCTRL);
 350         lpuart32_write(port, temp & ~UARTCTRL_RE, UARTCTRL);
 351 }
 352
 353 static void lpuart_dma_tx(struct lpuart_port *sport)
 354 {
 355         struct circ_buf *xmit = &sport->port.state->xmit;
 356         struct scatterlist *sgl = sport->tx_sgl;
 357         struct device *dev = sport->port.dev;
 358         int ret;
 359
 360         if (sport->dma_tx_in_progress)
 361                 return;
 362
 363         sport->dma_tx_bytes = uart_circ_chars_pending(xmit);
 364
 365         if (xmit->tail < xmit->head || xmit->head == 0) {
 366                 sport->dma_tx_nents = 1;
 367                 sg_init_one(sgl, xmit->buf + xmit->tail, sport->dma_tx_bytes);
 368         } else {
 369                 sport->dma_tx_nents = 2;
 370                 sg_init_table(sgl, 2);
 371                 sg_set_buf(sgl, xmit->buf + xmit->tail,
 372                                 UART_XMIT_SIZE - xmit->tail);
 373                 sg_set_buf(sgl + 1, xmit->buf, xmit->head);
 374         }
 375
 376         ret = dma_map_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
 377         if (!ret) {
 378                 dev_err(dev, "DMA mapping error for TX.\n");
 379                 return;
 380         }
 381
 382         sport->dma_tx_desc = dmaengine_prep_slave_sg(sport->dma_tx_chan, sgl,
 383                                         ret, DMA_MEM_TO_DEV,
 384                                         DMA_PREP_INTERRUPT);
 385         if (!sport->dma_tx_desc) {
 386                 dma_unmap_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
 387                 dev_err(dev, "Cannot prepare TX slave DMA!\n");
 388                 return;
 389         }
 390
 391         sport->dma_tx_desc->callback = lpuart_dma_tx_complete;
 392         sport->dma_tx_desc->callback_param = sport;
 393         sport->dma_tx_in_progress = true;
 394         sport->dma_tx_cookie = dmaengine_submit(sport->dma_tx_desc);
 395         dma_async_issue_pending(sport->dma_tx_chan);
 396 }
 397
 398 static void lpuart_dma_tx_complete(void *arg)
 399 {
 400         struct lpuart_port *sport = arg;
 401         struct scatterlist *sgl = &sport->tx_sgl[0];
 402         struct circ_buf *xmit = &sport->port.state->xmit;
 403         unsigned long flags;
 404
 405         spin_lock_irqsave(&sport->port.lock, flags);
 406
 407         dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
 408
 409         xmit->tail = (xmit->tail + sport->dma_tx_bytes) & (UART_XMIT_SIZE - 1);
 410
 411         sport->port.icount.tx += sport->dma_tx_bytes;
 412         sport->dma_tx_in_progress = false;
 413         spin_unlock_irqrestore(&sport->port.lock, flags);
 414
 415         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 416                 uart_write_wakeup(&sport->port);
 417
 418         if (waitqueue_active(&sport->dma_wait)) {
 419                 wake_up(&sport->dma_wait);
 420                 return;
 421         }
 422
 423         spin_lock_irqsave(&sport->port.lock, flags);
 424
 425         if (!uart_circ_empty(xmit) && !uart_tx_stopped(&sport->port))
 426                 lpuart_dma_tx(sport);
 427
 428         spin_unlock_irqrestore(&sport->port.lock, flags);
 429 }
 430
 431 static int lpuart_dma_tx_request(struct uart_port *port)
 432 {
 433         struct lpuart_port *sport = container_of(port,
 434                                         struct lpuart_port, port);
 435         struct dma_slave_config dma_tx_sconfig = {};
 436         int ret;
 437
 438         dma_tx_sconfig.dst_addr = sport->port.mapbase + UARTDR;
 439         dma_tx_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 440         dma_tx_sconfig.dst_maxburst = 1;
 441         dma_tx_sconfig.direction = DMA_MEM_TO_DEV;
 442         ret = dmaengine_slave_config(sport->dma_tx_chan, &dma_tx_sconfig);
 443
 444         if (ret) {
 445                 dev_err(sport->port.dev,
 446                                 "DMA slave config failed, err = %d\n", ret);
 447                 return ret;
 448         }
 449
 450         return 0;
 451 }
 452
 453 static void lpuart_flush_buffer(struct uart_port *port)
 454 {
 455         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 456
 457         if (sport->lpuart_dma_tx_use) {
 458                 if (sport->dma_tx_in_progress) {
 459                         dma_unmap_sg(sport->port.dev, &sport->tx_sgl[0],
 460                                 sport->dma_tx_nents, DMA_TO_DEVICE);
 461                         sport->dma_tx_in_progress = false;
 462                 }
 463                 dmaengine_terminate_all(sport->dma_tx_chan);
 464         }
 465 }
 466
 467 #if defined(CONFIG_CONSOLE_POLL)
 468
 469 static int lpuart_poll_init(struct uart_port *port)
 470 {
 471         struct lpuart_port *sport = container_of(port,
 472                                         struct lpuart_port, port);
 473         unsigned long flags;
 474         unsigned char temp;
 475
 476         sport->port.fifosize = 0;
 477
 478         spin_lock_irqsave(&sport->port.lock, flags);
 479         /* Disable Rx & Tx */
 480         writeb(0, sport->port.membase + UARTCR2);
 481
 482         temp = readb(sport->port.membase + UARTPFIFO);
 483         /* Enable Rx and Tx FIFO */
 484         writeb(temp | UARTPFIFO_RXFE | UARTPFIFO_TXFE,
 485                         sport->port.membase + UARTPFIFO);
 486
 487         /* flush Tx and Rx FIFO */
 488         writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
 489                         sport->port.membase + UARTCFIFO);
 490
 491         /* explicitly clear RDRF */
 492         if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
 493                 readb(sport->port.membase + UARTDR);
 494                 writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
 495         }
 496
 497         writeb(0, sport->port.membase + UARTTWFIFO);
 498         writeb(1, sport->port.membase + UARTRWFIFO);
 499
 500         /* Enable Rx and Tx */
 501         writeb(UARTCR2_RE | UARTCR2_TE, sport->port.membase + UARTCR2);
 502         spin_unlock_irqrestore(&sport->port.lock, flags);
 503
 504         return 0;
 505 }
 506
 507 static void lpuart_poll_put_char(struct uart_port *port, unsigned char c)
 508 {
 509         /* drain */
 510         while (!(readb(port->membase + UARTSR1) & UARTSR1_TDRE))
 511                 barrier();
 512
 513         writeb(c, port->membase + UARTDR);
 514 }
 515
 516 static int lpuart_poll_get_char(struct uart_port *port)
 517 {
 518         if (!(readb(port->membase + UARTSR1) & UARTSR1_RDRF))
 519                 return NO_POLL_CHAR;
 520
 521         return readb(port->membase + UARTDR);
 522 }
 523
 524 static int lpuart32_poll_init(struct uart_port *port)
 525 {
 526         unsigned long flags;
 527         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 528         u32 temp;
 529
 530         sport->port.fifosize = 0;
 531
 532         spin_lock_irqsave(&sport->port.lock, flags);
 533
 534         /* Disable Rx & Tx */
 535         lpuart32_write(&sport->port, UARTCTRL, 0);
 536
 537         temp = lpuart32_read(&sport->port, UARTFIFO);
 538
 539         /* Enable Rx and Tx FIFO */
 540         lpuart32_write(&sport->port, UARTFIFO,
 541                        temp | UARTFIFO_RXFE | UARTFIFO_TXFE);
 542
 543         /* flush Tx and Rx FIFO */
 544         lpuart32_write(&sport->port, UARTFIFO,
 545                        UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH);
 546
 547         /* explicitly clear RDRF */
 548         if (lpuart32_read(&sport->port, UARTSTAT) & UARTSTAT_RDRF) {
 549                 lpuart32_read(&sport->port, UARTDATA);
 550                 lpuart32_write(&sport->port, UARTFIFO, UARTFIFO_RXUF);
 551         }
 552
 553         /* Enable Rx and Tx */
 554         lpuart32_write(&sport->port, UARTCTRL, UARTCTRL_RE | UARTCTRL_TE);
 555         spin_unlock_irqrestore(&sport->port.lock, flags);
 556
 557         return 0;
 558 }
 559
 560 static void lpuart32_poll_put_char(struct uart_port *port, unsigned char c)
 561 {
 562         while (!(lpuart32_read(port, UARTSTAT) & UARTSTAT_TDRE))
 563                 barrier();
 564
 565         lpuart32_write(port, UARTDATA, c);
 566 }
 567
 568 static int lpuart32_poll_get_char(struct uart_port *port)
 569 {
 570         if (!(lpuart32_read(port, UARTWATER) >> UARTWATER_RXCNT_OFF))
 571                 return NO_POLL_CHAR;
 572
 573         return lpuart32_read(port, UARTDATA);
 574 }
 575 #endif
 576
 577 static inline void lpuart_transmit_buffer(struct lpuart_port *sport)
 578 {
 579         struct circ_buf *xmit = &sport->port.state->xmit;
 580
 581         while (!uart_circ_empty(xmit) &&
 582                 (readb(sport->port.membase + UARTTCFIFO) < sport->txfifo_size)) {
 583                 writeb(xmit->buf[xmit->tail], sport->port.membase + UARTDR);
 584                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 585                 sport->port.icount.tx++;
 586         }
 587
 588         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 589                 uart_write_wakeup(&sport->port);
 590
 591         if (uart_circ_empty(xmit))
 592                 lpuart_stop_tx(&sport->port);
 593 }
 594
 595 static inline void lpuart32_transmit_buffer(struct lpuart_port *sport)
 596 {
 597         struct circ_buf *xmit = &sport->port.state->xmit;
 598         unsigned long txcnt;
 599
 600         txcnt = lpuart32_read(&sport->port, UARTWATER);
 601         txcnt = txcnt >> UARTWATER_TXCNT_OFF;
 602         txcnt &= UARTWATER_COUNT_MASK;
 603         while (!uart_circ_empty(xmit) && (txcnt < sport->txfifo_size)) {
 604                 lpuart32_write(&sport->port, xmit->buf[xmit->tail], UARTDATA);
 605                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 606                 sport->port.icount.tx++;
 607                 txcnt = lpuart32_read(&sport->port, UARTWATER);
 608                 txcnt = txcnt >> UARTWATER_TXCNT_OFF;
 609                 txcnt &= UARTWATER_COUNT_MASK;
 610         }
 611
 612         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 613                 uart_write_wakeup(&sport->port);
 614
 615         if (uart_circ_empty(xmit))
 616                 lpuart32_stop_tx(&sport->port);
 617 }
 618
 619 static void lpuart_start_tx(struct uart_port *port)
 620 {
 621         struct lpuart_port *sport = container_of(port,
 622                         struct lpuart_port, port);
 623         struct circ_buf *xmit = &sport->port.state->xmit;
 624         unsigned char temp;
 625
 626         temp = readb(port->membase + UARTCR2);
 627         writeb(temp | UARTCR2_TIE, port->membase + UARTCR2);
 628
 629         if (sport->lpuart_dma_tx_use) {
 630                 if (!uart_circ_empty(xmit) && !uart_tx_stopped(port))
 631                         lpuart_dma_tx(sport);
 632         } else {
 633                 if (readb(port->membase + UARTSR1) & UARTSR1_TDRE)
 634                         lpuart_transmit_buffer(sport);
 635         }
 636 }
 637
 638 static void lpuart32_start_tx(struct uart_port *port)
 639 {
 640         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 641         unsigned long temp;
 642
 643         temp = lpuart32_read(port, UARTCTRL);
 644         lpuart32_write(port, temp | UARTCTRL_TIE, UARTCTRL);
 645
 646         if (lpuart32_read(port, UARTSTAT) & UARTSTAT_TDRE)
 647                 lpuart32_transmit_buffer(sport);
 648 }
 649
 650 /* return TIOCSER_TEMT when transmitter is not busy */
 651 static unsigned int lpuart_tx_empty(struct uart_port *port)
 652 {
 653         struct lpuart_port *sport = container_of(port,
 654                         struct lpuart_port, port);
 655         unsigned char sr1 = readb(port->membase + UARTSR1);
 656         unsigned char sfifo = readb(port->membase + UARTSFIFO);
 657
 658         if (sport->dma_tx_in_progress)
 659                 return 0;
 660
 661         if (sr1 & UARTSR1_TC && sfifo & UARTSFIFO_TXEMPT)
 662                 return TIOCSER_TEMT;
 663
 664         return 0;
 665 }
 666
 667 static unsigned int lpuart32_tx_empty(struct uart_port *port)
 668 {
 669         return (lpuart32_read(port, UARTSTAT) & UARTSTAT_TC) ?
 670                 TIOCSER_TEMT : 0;
 671 }
 672
 673 static bool lpuart_is_32(struct lpuart_port *sport)
 674 {
 675         return sport->port.iotype == UPIO_MEM32 ||
 676                sport->port.iotype ==  UPIO_MEM32BE;
 677 }
 678
 679 static irqreturn_t lpuart_txint(int irq, void *dev_id)
 680 {
 681         struct lpuart_port *sport = dev_id;
 682         struct circ_buf *xmit = &sport->port.state->xmit;
 683         unsigned long flags;
 684
 685         spin_lock_irqsave(&sport->port.lock, flags);
 686         if (sport->port.x_char) {
 687                 if (lpuart_is_32(sport))
 688                         lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);
 689                 else
 690                         writeb(sport->port.x_char, sport->port.membase + UARTDR);
 691                 goto out;
 692         }
 693
 694         if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
 695                 if (lpuart_is_32(sport))
 696                         lpuart32_stop_tx(&sport->port);
 697                 else
 698                         lpuart_stop_tx(&sport->port);
 699                 goto out;
 700         }
 701
 702         if (lpuart_is_32(sport))
 703                 lpuart32_transmit_buffer(sport);
 704         else
 705                 lpuart_transmit_buffer(sport);
 706
 707         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 708                 uart_write_wakeup(&sport->port);
 709
 710 out:
 711         spin_unlock_irqrestore(&sport->port.lock, flags);
 712         return IRQ_HANDLED;
 713 }
 714
 715 static irqreturn_t lpuart_rxint(int irq, void *dev_id)
 716 {
 717         struct lpuart_port *sport = dev_id;
 718         unsigned int flg, ignored = 0;
 719         struct tty_port *port = &sport->port.state->port;
 720         unsigned long flags;
 721         unsigned char rx, sr;
 722
 723         spin_lock_irqsave(&sport->port.lock, flags);
 724
 725         while (!(readb(sport->port.membase + UARTSFIFO) & UARTSFIFO_RXEMPT)) {
 726                 flg = TTY_NORMAL;
 727                 sport->port.icount.rx++;
 728                 /*
 729                  * to clear the FE, OR, NF, FE, PE flags,
 730                  * read SR1 then read DR
 731                  */
 732                 sr = readb(sport->port.membase + UARTSR1);
 733                 rx = readb(sport->port.membase + UARTDR);
 734
 735                 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
 736                         continue;
 737
 738                 if (sr & (UARTSR1_PE | UARTSR1_OR | UARTSR1_FE)) {
 739                         if (sr & UARTSR1_PE)
 740                                 sport->port.icount.parity++;
 741                         else if (sr & UARTSR1_FE)
 742                                 sport->port.icount.frame++;
 743
 744                         if (sr & UARTSR1_OR)
 745                                 sport->port.icount.overrun++;
 746
 747                         if (sr & sport->port.ignore_status_mask) {
 748                                 if (++ignored > 100)
 749                                         goto out;
 750                                 continue;
 751                         }
 752
 753                         sr &= sport->port.read_status_mask;
 754
 755                         if (sr & UARTSR1_PE)
 756                                 flg = TTY_PARITY;
 757                         else if (sr & UARTSR1_FE)
 758                                 flg = TTY_FRAME;
 759
 760                         if (sr & UARTSR1_OR)
 761                                 flg = TTY_OVERRUN;
 762
 763 #ifdef SUPPORT_SYSRQ
 764                         sport->port.sysrq = 0;
 765 #endif
 766                 }
 767
 768                 tty_insert_flip_char(port, rx, flg);
 769         }
 770
 771 out:
 772         spin_unlock_irqrestore(&sport->port.lock, flags);
 773
 774         tty_flip_buffer_push(port);
 775         return IRQ_HANDLED;
 776 }
 777
 778 static irqreturn_t lpuart32_rxint(int irq, void *dev_id)
 779 {
 780         struct lpuart_port *sport = dev_id;
 781         unsigned int flg, ignored = 0;
 782         struct tty_port *port = &sport->port.state->port;
 783         unsigned long flags;
 784         unsigned long rx, sr;
 785
 786         spin_lock_irqsave(&sport->port.lock, flags);
 787
 788         while (!(lpuart32_read(&sport->port, UARTFIFO) & UARTFIFO_RXEMPT)) {
 789                 flg = TTY_NORMAL;
 790                 sport->port.icount.rx++;
 791                 /*
 792                  * to clear the FE, OR, NF, FE, PE flags,
 793                  * read STAT then read DATA reg
 794                  */
 795                 sr = lpuart32_read(&sport->port, UARTSTAT);
 796                 rx = lpuart32_read(&sport->port, UARTDATA);
 797                 rx &= 0x3ff;
 798
 799                 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
 800                         continue;
 801
 802                 if (sr & (UARTSTAT_PE | UARTSTAT_OR | UARTSTAT_FE)) {
 803                         if (sr & UARTSTAT_PE)
 804                                 sport->port.icount.parity++;
 805                         else if (sr & UARTSTAT_FE)
 806                                 sport->port.icount.frame++;
 807
 808                         if (sr & UARTSTAT_OR)
 809                                 sport->port.icount.overrun++;
 810
 811                         if (sr & sport->port.ignore_status_mask) {
 812                                 if (++ignored > 100)
 813                                         goto out;
 814                                 continue;
 815                         }
 816
 817                         sr &= sport->port.read_status_mask;
 818
 819                         if (sr & UARTSTAT_PE)
 820                                 flg = TTY_PARITY;
 821                         else if (sr & UARTSTAT_FE)
 822                                 flg = TTY_FRAME;
 823
 824                         if (sr & UARTSTAT_OR)
 825                                 flg = TTY_OVERRUN;
 826
 827 #ifdef SUPPORT_SYSRQ
 828                         sport->port.sysrq = 0;
 829 #endif
 830                 }
 831
 832                 tty_insert_flip_char(port, rx, flg);
 833         }
 834
 835 out:
 836         spin_unlock_irqrestore(&sport->port.lock, flags);
 837
 838         tty_flip_buffer_push(port);
 839         return IRQ_HANDLED;
 840 }
 841
 842 static irqreturn_t lpuart_int(int irq, void *dev_id)
 843 {
 844         struct lpuart_port *sport = dev_id;
 845         unsigned char sts;
 846
 847         sts = readb(sport->port.membase + UARTSR1);
 848
 849         if (sts & UARTSR1_RDRF)
 850                 lpuart_rxint(irq, dev_id);
 851
 852         if (sts & UARTSR1_TDRE)
 853                 lpuart_txint(irq, dev_id);
 854
 855         return IRQ_HANDLED;
 856 }
 857
 858 static irqreturn_t lpuart32_int(int irq, void *dev_id)
 859 {
 860         struct lpuart_port *sport = dev_id;
 861         unsigned long sts, rxcount;
 862
 863         sts = lpuart32_read(&sport->port, UARTSTAT);
 864         rxcount = lpuart32_read(&sport->port, UARTWATER);
 865         rxcount = rxcount >> UARTWATER_RXCNT_OFF;
 866
 867         if (sts & UARTSTAT_RDRF || rxcount > 0)
 868                 lpuart32_rxint(irq, dev_id);
 869
 870         if ((sts & UARTSTAT_TDRE) &&
 871                 !(lpuart32_read(&sport->port, UARTBAUD) & UARTBAUD_TDMAE))
 872                 lpuart_txint(irq, dev_id);
 873
 874         lpuart32_write(&sport->port, sts, UARTSTAT);
 875         return IRQ_HANDLED;
 876 }
 877
 878 static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
 879 {
 880         struct tty_port *port = &sport->port.state->port;
 881         struct dma_tx_state state;
 882         enum dma_status dmastat;
 883         struct circ_buf *ring = &sport->rx_ring;
 884         unsigned long flags;
 885         int count = 0;
 886         unsigned char sr;
 887
 888         sr = readb(sport->port.membase + UARTSR1);
 889
 890         if (sr & (UARTSR1_PE | UARTSR1_FE)) {
 891                 /* Read DR to clear the error flags */
 892                 readb(sport->port.membase + UARTDR);
 893
 894                 if (sr & UARTSR1_PE)
 895                     sport->port.icount.parity++;
 896                 else if (sr & UARTSR1_FE)
 897                     sport->port.icount.frame++;
 898         }
 899
 900         async_tx_ack(sport->dma_rx_desc);
 901
 902         spin_lock_irqsave(&sport->port.lock, flags);
 903
 904         dmastat = dmaengine_tx_status(sport->dma_rx_chan,
 905                                 sport->dma_rx_cookie,
 906                                 &state);
 907
 908         if (dmastat == DMA_ERROR) {
 909                 dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
 910                 spin_unlock_irqrestore(&sport->port.lock, flags);
 911                 return;
 912         }
 913
 914         /* CPU claims ownership of RX DMA buffer */
 915         dma_sync_sg_for_cpu(sport->port.dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
 916
 917         /*
 918          * ring->head points to the end of data already written by the DMA.
 919          * ring->tail points to the beginning of data to be read by the
 920          * framework.
 921          * The current transfer size should not be larger than the dma buffer
 922          * length.
 923          */
 924         ring->head = sport->rx_sgl.length - state.residue;
 925         BUG_ON(ring->head > sport->rx_sgl.length);
 926         /*
 927          * At this point ring->head may point to the first byte right after the
 928          * last byte of the dma buffer:
 929          * 0 <= ring->head <= sport->rx_sgl.length
 930          *
 931          * However ring->tail must always points inside the dma buffer:
 932          * 0 <= ring->tail <= sport->rx_sgl.length - 1
 933          *
 934          * Since we use a ring buffer, we have to handle the case
 935          * where head is lower than tail. In such a case, we first read from
 936          * tail to the end of the buffer then reset tail.
 937          */
 938         if (ring->head < ring->tail) {
 939                 count = sport->rx_sgl.length - ring->tail;
 940
 941                 tty_insert_flip_string(port, ring->buf + ring->tail, count);
 942                 ring->tail = 0;
 943                 sport->port.icount.rx += count;
 944         }
 945
 946         /* Finally we read data from tail to head */
 947         if (ring->tail < ring->head) {
 948                 count = ring->head - ring->tail;
 949                 tty_insert_flip_string(port, ring->buf + ring->tail, count);
 950                 /* Wrap ring->head if needed */
 951                 if (ring->head >= sport->rx_sgl.length)
 952                         ring->head = 0;
 953                 ring->tail = ring->head;
 954                 sport->port.icount.rx += count;
 955         }
 956
 957         dma_sync_sg_for_device(sport->port.dev, &sport->rx_sgl, 1,
 958                                DMA_FROM_DEVICE);
 959
 960         spin_unlock_irqrestore(&sport->port.lock, flags);
 961
 962         tty_flip_buffer_push(port);
 963         mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
 964 }
 965
 966 static void lpuart_dma_rx_complete(void *arg)
 967 {
 968         struct lpuart_port *sport = arg;
 969
 970         lpuart_copy_rx_to_tty(sport);
 971 }
 972
 973 static void lpuart_timer_func(unsigned long data)
 974 {
 975         struct lpuart_port *sport = (struct lpuart_port *)data;
 976
 977         lpuart_copy_rx_to_tty(sport);
 978 }
 979
 980 static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
 981 {
 982         struct dma_slave_config dma_rx_sconfig = {};
 983         struct circ_buf *ring = &sport->rx_ring;
 984         int ret, nent;
 985         int bits, baud;
 986         struct tty_port *port = &sport->port.state->port;
 987         struct tty_struct *tty = port->tty;
 988         struct ktermios *termios = &tty->termios;
 989
 990         baud = tty_get_baud_rate(tty);
 991
 992         bits = (termios->c_cflag & CSIZE) == CS7 ? 9 : 10;
 993         if (termios->c_cflag & PARENB)
 994                 bits++;
 995
 996         /*
 997          * Calculate length of one DMA buffer size to keep latency below
 998          * 10ms at any baud rate.
 999          */
1000         sport->rx_dma_rng_buf_len = (DMA_RX_TIMEOUT * baud /  bits / 1000) * 2;
1001         sport->rx_dma_rng_buf_len = (1 << (fls(sport->rx_dma_rng_buf_len) - 1));
1002         if (sport->rx_dma_rng_buf_len < 16)
1003                 sport->rx_dma_rng_buf_len = 16;
1004
1005         ring->buf = kmalloc(sport->rx_dma_rng_buf_len, GFP_ATOMIC);
1006         if (!ring->buf) {
1007                 dev_err(sport->port.dev, "Ring buf alloc failed\n");
1008                 return -ENOMEM;
1009         }
1010
1011         sg_init_one(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
1012         sg_set_buf(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
1013         nent = dma_map_sg(sport->port.dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
1014
1015         if (!nent) {
1016                 dev_err(sport->port.dev, "DMA Rx mapping error\n");
1017                 return -EINVAL;
1018         }
1019
1020         dma_rx_sconfig.src_addr = sport->port.mapbase + UARTDR;
1021         dma_rx_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1022         dma_rx_sconfig.src_maxburst = 1;
1023         dma_rx_sconfig.direction = DMA_DEV_TO_MEM;
1024         ret = dmaengine_slave_config(sport->dma_rx_chan, &dma_rx_sconfig);
1025
1026         if (ret < 0) {
1027                 dev_err(sport->port.dev,
1028                                 "DMA Rx slave config failed, err = %d\n", ret);
1029                 return ret;
1030         }
1031
1032         sport->dma_rx_desc = dmaengine_prep_dma_cyclic(sport->dma_rx_chan,
1033                                  sg_dma_address(&sport->rx_sgl),
1034                                  sport->rx_sgl.length,
1035                                  sport->rx_sgl.length / 2,
1036                                  DMA_DEV_TO_MEM,
1037                                  DMA_PREP_INTERRUPT);
1038         if (!sport->dma_rx_desc) {
1039                 dev_err(sport->port.dev, "Cannot prepare cyclic DMA\n");
1040                 return -EFAULT;
1041         }
1042
1043         sport->dma_rx_desc->callback = lpuart_dma_rx_complete;
1044         sport->dma_rx_desc->callback_param = sport;
1045         sport->dma_rx_cookie = dmaengine_submit(sport->dma_rx_desc);
1046         dma_async_issue_pending(sport->dma_rx_chan);
1047
1048         writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_RDMAS,
1049                                 sport->port.membase + UARTCR5);
1050
1051         return 0;
1052 }
1053
1054 static void lpuart_dma_rx_free(struct uart_port *port)
1055 {
1056         struct lpuart_port *sport = container_of(port,
1057                                         struct lpuart_port, port);
1058
1059         if (sport->dma_rx_chan)
1060                 dmaengine_terminate_all(sport->dma_rx_chan);
1061
1062         dma_unmap_sg(sport->port.dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
1063         kfree(sport->rx_ring.buf);
1064         sport->rx_ring.tail = 0;
1065         sport->rx_ring.head = 0;
1066         sport->dma_rx_desc = NULL;
1067         sport->dma_rx_cookie = -EINVAL;
1068 }
1069
1070 static int lpuart_config_rs485(struct uart_port *port,
1071                         struct serial_rs485 *rs485)
1072 {
1073         struct lpuart_port *sport = container_of(port,
1074                         struct lpuart_port, port);
1075
1076         u8 modem = readb(sport->port.membase + UARTMODEM) &
1077                 ~(UARTMODEM_TXRTSPOL | UARTMODEM_TXRTSE);
1078         writeb(modem, sport->port.membase + UARTMODEM);
1079
1080         /* clear unsupported configurations */
1081         rs485->delay_rts_before_send = 0;
1082         rs485->delay_rts_after_send = 0;
1083         rs485->flags &= ~SER_RS485_RX_DURING_TX;
1084
1085         if (rs485->flags & SER_RS485_ENABLED) {
1086                 /* Enable auto RS-485 RTS mode */
1087                 modem |= UARTMODEM_TXRTSE;
1088
1089                 /*
1090                  * RTS needs to be logic HIGH either during transer _or_ after
1091                  * transfer, other variants are not supported by the hardware.
1092                  */
1093
1094                 if (!(rs485->flags & (SER_RS485_RTS_ON_SEND |
1095                                 SER_RS485_RTS_AFTER_SEND)))
1096                         rs485->flags |= SER_RS485_RTS_ON_SEND;
1097
1098                 if (rs485->flags & SER_RS485_RTS_ON_SEND &&
1099                                 rs485->flags & SER_RS485_RTS_AFTER_SEND)
1100                         rs485->flags &= ~SER_RS485_RTS_AFTER_SEND;
1101
1102                 /*
1103                  * The hardware defaults to RTS logic HIGH while transfer.
1104                  * Switch polarity in case RTS shall be logic HIGH
1105                  * after transfer.
1106                  * Note: UART is assumed to be active high.
1107                  */
1108                 if (rs485->flags & SER_RS485_RTS_ON_SEND)
1109                         modem |= UARTMODEM_TXRTSPOL;
1110                 else if (rs485->flags & SER_RS485_RTS_AFTER_SEND)
1111                         modem &= ~UARTMODEM_TXRTSPOL;
1112         }
1113
1114         /* Store the new configuration */
1115         sport->port.rs485 = *rs485;
1116
1117         writeb(modem, sport->port.membase + UARTMODEM);
1118         return 0;
1119 }
1120
1121 static unsigned int lpuart_get_mctrl(struct uart_port *port)
1122 {
1123         unsigned int temp = 0;
1124         unsigned char reg;
1125
1126         reg = readb(port->membase + UARTMODEM);
1127         if (reg & UARTMODEM_TXCTSE)
1128                 temp |= TIOCM_CTS;
1129
1130         if (reg & UARTMODEM_RXRTSE)
1131                 temp |= TIOCM_RTS;
1132
1133         return temp;
1134 }
1135
1136 static unsigned int lpuart32_get_mctrl(struct uart_port *port)
1137 {
1138         unsigned int temp = 0;
1139         unsigned long reg;
1140
1141         reg = lpuart32_read(port, UARTMODIR);
1142         if (reg & UARTMODIR_TXCTSE)
1143                 temp |= TIOCM_CTS;
1144
1145         if (reg & UARTMODIR_RXRTSE)
1146                 temp |= TIOCM_RTS;
1147
1148         return temp;
1149 }
1150
1151 static void lpuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1152 {
1153         unsigned char temp;
1154         struct lpuart_port *sport = container_of(port,
1155                                 struct lpuart_port, port);
1156
1157         /* Make sure RXRTSE bit is not set when RS485 is enabled */
1158         if (!(sport->port.rs485.flags & SER_RS485_ENABLED)) {
1159                 temp = readb(sport->port.membase + UARTMODEM) &
1160                         ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1161
1162                 if (mctrl & TIOCM_RTS)
1163                         temp |= UARTMODEM_RXRTSE;
1164
1165                 if (mctrl & TIOCM_CTS)
1166                         temp |= UARTMODEM_TXCTSE;
1167
1168                 writeb(temp, port->membase + UARTMODEM);
1169         }
1170 }
1171
1172 static void lpuart32_set_mctrl(struct uart_port *port, unsigned int mctrl)
1173 {
1174         unsigned long temp;
1175
1176         temp = lpuart32_read(port, UARTMODIR) &
1177                         ~(UARTMODIR_RXRTSE | UARTMODIR_TXCTSE);
1178
1179         if (mctrl & TIOCM_RTS)
1180                 temp |= UARTMODIR_RXRTSE;
1181
1182         if (mctrl & TIOCM_CTS)
1183                 temp |= UARTMODIR_TXCTSE;
1184
1185         lpuart32_write(port, temp, UARTMODIR);
1186 }
1187
1188 static void lpuart_break_ctl(struct uart_port *port, int break_state)
1189 {
1190         unsigned char temp;
1191
1192         temp = readb(port->membase + UARTCR2) & ~UARTCR2_SBK;
1193
1194         if (break_state != 0)
1195                 temp |= UARTCR2_SBK;
1196
1197         writeb(temp, port->membase + UARTCR2);
1198 }
1199
1200 static void lpuart32_break_ctl(struct uart_port *port, int break_state)
1201 {
1202         unsigned long temp, modem;
1203         struct tty_struct *tty;
1204         unsigned int cflag = 0;
1205
1206         tty = tty_port_tty_get(&port->state->port);
1207         if (tty) {
1208                 cflag = tty->termios.c_cflag;
1209                 tty_kref_put(tty);
1210         }
1211
1212         temp = lpuart32_read(port, UARTCTRL) & ~UARTCTRL_SBK;
1213         modem = lpuart32_read(port, UARTMODIR);
1214
1215         if (break_state != 0) {
1216                 temp |= UARTCTRL_SBK;
1217                 /*
1218                  * LPUART CTS has higher priority than SBK, need to disable CTS before
1219                  * asserting SBK to avoid any interference if flow control is enabled.
1220                  */
1221                 if (cflag & CRTSCTS && modem & UARTMODIR_TXCTSE)
1222                         lpuart32_write(port, modem & ~UARTMODIR_TXCTSE, UARTMODIR);
1223         } else {
1224                 /* Re-enable the CTS when break off. */
1225                 if (cflag & CRTSCTS && !(modem & UARTMODIR_TXCTSE))
1226                         lpuart32_write(port, modem | UARTMODIR_TXCTSE, UARTMODIR);
1227         }
1228
1229         lpuart32_write(port, temp, UARTCTRL);
1230 }
1231
1232 static void lpuart_setup_watermark(struct lpuart_port *sport)
1233 {
1234         unsigned char val, cr2;
1235         unsigned char cr2_saved;
1236
1237         cr2 = readb(sport->port.membase + UARTCR2);
1238         cr2_saved = cr2;
1239         cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_TE |
1240                         UARTCR2_RIE | UARTCR2_RE);
1241         writeb(cr2, sport->port.membase + UARTCR2);
1242
1243         val = readb(sport->port.membase + UARTPFIFO);
1244         writeb(val | UARTPFIFO_TXFE | UARTPFIFO_RXFE,
1245                         sport->port.membase + UARTPFIFO);
1246
1247         /* flush Tx and Rx FIFO */
1248         writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
1249                         sport->port.membase + UARTCFIFO);
1250
1251         /* explicitly clear RDRF */
1252         if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
1253                 readb(sport->port.membase + UARTDR);
1254                 writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
1255         }
1256
1257         writeb(0, sport->port.membase + UARTTWFIFO);
1258         writeb(1, sport->port.membase + UARTRWFIFO);
1259
1260         /* Restore cr2 */
1261         writeb(cr2_saved, sport->port.membase + UARTCR2);
1262 }
1263
1264 static void lpuart32_setup_watermark(struct lpuart_port *sport)
1265 {
1266         unsigned long val, ctrl;
1267         unsigned long ctrl_saved;
1268
1269         ctrl = lpuart32_read(&sport->port, UARTCTRL);
1270         ctrl_saved = ctrl;
1271         ctrl &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_TE |
1272                         UARTCTRL_RIE | UARTCTRL_RE);
1273         lpuart32_write(&sport->port, ctrl, UARTCTRL);
1274
1275         /* enable FIFO mode */
1276         val = lpuart32_read(&sport->port, UARTFIFO);
1277         val |= UARTFIFO_TXFE | UARTFIFO_RXFE;
1278         val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
1279         lpuart32_write(&sport->port, val, UARTFIFO);
1280
1281         /* set the watermark */
1282         val = (0x1 << UARTWATER_RXWATER_OFF) | (0x0 << UARTWATER_TXWATER_OFF);
1283         lpuart32_write(&sport->port, val, UARTWATER);
1284
1285         /* Restore cr2 */
1286         lpuart32_write(&sport->port, ctrl_saved, UARTCTRL);
1287 }
1288
1289 static void rx_dma_timer_init(struct lpuart_port *sport)
1290 {
1291                 setup_timer(&sport->lpuart_timer, lpuart_timer_func,
1292                                 (unsigned long)sport);
1293                 sport->lpuart_timer.expires = jiffies + sport->dma_rx_timeout;
1294                 add_timer(&sport->lpuart_timer);
1295 }
1296
1297 static int lpuart_startup(struct uart_port *port)
1298 {
1299         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1300         unsigned long flags;
1301         unsigned char temp;
1302
1303         /* determine FIFO size and enable FIFO mode */
1304         temp = readb(sport->port.membase + UARTPFIFO);
1305
1306         sport->txfifo_size = 0x1 << (((temp >> UARTPFIFO_TXSIZE_OFF) &
1307                 UARTPFIFO_FIFOSIZE_MASK) + 1);
1308
1309         sport->port.fifosize = sport->txfifo_size;
1310
1311         sport->rxfifo_size = 0x1 << (((temp >> UARTPFIFO_RXSIZE_OFF) &
1312                 UARTPFIFO_FIFOSIZE_MASK) + 1);
1313
1314         spin_lock_irqsave(&sport->port.lock, flags);
1315
1316         lpuart_setup_watermark(sport);
1317
1318         temp = readb(sport->port.membase + UARTCR2);
1319         temp |= (UARTCR2_RIE | UARTCR2_TIE | UARTCR2_RE | UARTCR2_TE);
1320         writeb(temp, sport->port.membase + UARTCR2);
1321
1322         if (sport->dma_rx_chan && !lpuart_start_rx_dma(sport)) {
1323                 /* set Rx DMA timeout */
1324                 sport->dma_rx_timeout = msecs_to_jiffies(DMA_RX_TIMEOUT);
1325                 if (!sport->dma_rx_timeout)
1326                      sport->dma_rx_timeout = 1;
1327
1328                 sport->lpuart_dma_rx_use = true;
1329                 rx_dma_timer_init(sport);
1330         } else {
1331                 sport->lpuart_dma_rx_use = false;
1332         }
1333
1334         if (sport->dma_tx_chan && !lpuart_dma_tx_request(port)) {
1335                 init_waitqueue_head(&sport->dma_wait);
1336                 sport->lpuart_dma_tx_use = true;
1337                 temp = readb(port->membase + UARTCR5);
1338                 writeb(temp | UARTCR5_TDMAS, port->membase + UARTCR5);
1339         } else {
1340                 sport->lpuart_dma_tx_use = false;
1341         }
1342
1343         spin_unlock_irqrestore(&sport->port.lock, flags);
1344
1345         return 0;
1346 }
1347
1348 static int lpuart32_startup(struct uart_port *port)
1349 {
1350         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1351         unsigned long flags;
1352         unsigned long temp;
1353
1354         /* determine FIFO size */
1355         temp = lpuart32_read(&sport->port, UARTFIFO);
1356
1357         sport->txfifo_size = 0x1 << (((temp >> UARTFIFO_TXSIZE_OFF) &
1358                 UARTFIFO_FIFOSIZE_MASK) - 1);
1359
1360         sport->rxfifo_size = 0x1 << (((temp >> UARTFIFO_RXSIZE_OFF) &
1361                 UARTFIFO_FIFOSIZE_MASK) - 1);
1362
1363         spin_lock_irqsave(&sport->port.lock, flags);
1364
1365         lpuart32_setup_watermark(sport);
1366
1367         temp = lpuart32_read(&sport->port, UARTCTRL);
1368         temp |= (UARTCTRL_RIE | UARTCTRL_TIE | UARTCTRL_RE | UARTCTRL_TE);
1369         temp |= UARTCTRL_ILIE;
1370         lpuart32_write(&sport->port, temp, UARTCTRL);
1371
1372         spin_unlock_irqrestore(&sport->port.lock, flags);
1373         return 0;
1374 }
1375
1376 static void lpuart_shutdown(struct uart_port *port)
1377 {
1378         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1379         unsigned char temp;
1380         unsigned long flags;
1381
1382         spin_lock_irqsave(&port->lock, flags);
1383
1384         /* disable Rx/Tx and interrupts */
1385         temp = readb(port->membase + UARTCR2);
1386         temp &= ~(UARTCR2_TE | UARTCR2_RE |
1387                         UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
1388         writeb(temp, port->membase + UARTCR2);
1389
1390         spin_unlock_irqrestore(&port->lock, flags);
1391
1392         if (sport->lpuart_dma_rx_use) {
1393                 del_timer_sync(&sport->lpuart_timer);
1394                 lpuart_dma_rx_free(&sport->port);
1395         }
1396
1397         if (sport->lpuart_dma_tx_use) {
1398                 if (wait_event_interruptible(sport->dma_wait,
1399                         !sport->dma_tx_in_progress) != false) {
1400                         sport->dma_tx_in_progress = false;
1401                         dmaengine_terminate_all(sport->dma_tx_chan);
1402                 }
1403
1404                 lpuart_stop_tx(port);
1405         }
1406 }
1407
1408 static void lpuart32_shutdown(struct uart_port *port)
1409 {
1410         unsigned long temp;
1411         unsigned long flags;
1412
1413         spin_lock_irqsave(&port->lock, flags);
1414
1415         /* disable Rx/Tx and interrupts */
1416         temp = lpuart32_read(port, UARTCTRL);
1417         temp &= ~(UARTCTRL_TE | UARTCTRL_RE |
1418                         UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
1419         lpuart32_write(port, temp, UARTCTRL);
1420
1421         spin_unlock_irqrestore(&port->lock, flags);
1422 }
1423
1424 static void
1425 lpuart_set_termios(struct uart_port *port, struct ktermios *termios,
1426                    struct ktermios *old)
1427 {
1428         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1429         unsigned long flags;
1430         unsigned char cr1, old_cr1, old_cr2, cr3, cr4, bdh, modem;
1431         unsigned int  baud;
1432         unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1433         unsigned int sbr, brfa;
1434
1435         cr1 = old_cr1 = readb(sport->port.membase + UARTCR1);
1436         old_cr2 = readb(sport->port.membase + UARTCR2);
1437         cr3 = readb(sport->port.membase + UARTCR3);
1438         cr4 = readb(sport->port.membase + UARTCR4);
1439         bdh = readb(sport->port.membase + UARTBDH);
1440         modem = readb(sport->port.membase + UARTMODEM);
1441         /*
1442          * only support CS8 and CS7, and for CS7 must enable PE.
1443          * supported mode:
1444          *  - (7,e/o,1)
1445          *  - (8,n,1)
1446          *  - (8,m/s,1)
1447          *  - (8,e/o,1)
1448          */
1449         while ((termios->c_cflag & CSIZE) != CS8 &&
1450                 (termios->c_cflag & CSIZE) != CS7) {
1451                 termios->c_cflag &= ~CSIZE;
1452                 termios->c_cflag |= old_csize;
1453                 old_csize = CS8;
1454         }
1455
1456         if ((termios->c_cflag & CSIZE) == CS8 ||
1457                 (termios->c_cflag & CSIZE) == CS7)
1458                 cr1 = old_cr1 & ~UARTCR1_M;
1459
1460         if (termios->c_cflag & CMSPAR) {
1461                 if ((termios->c_cflag & CSIZE) != CS8) {
1462                         termios->c_cflag &= ~CSIZE;
1463                         termios->c_cflag |= CS8;
1464                 }
1465                 cr1 |= UARTCR1_M;
1466         }
1467
1468         /*
1469          * When auto RS-485 RTS mode is enabled,
1470          * hardware flow control need to be disabled.
1471          */
1472         if (sport->port.rs485.flags & SER_RS485_ENABLED)
1473                 termios->c_cflag &= ~CRTSCTS;
1474
1475         if (termios->c_cflag & CRTSCTS) {
1476                 modem |= (UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1477         } else {
1478                 termios->c_cflag &= ~CRTSCTS;
1479                 modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1480         }
1481
1482         if (termios->c_cflag & CSTOPB)
1483                 termios->c_cflag &= ~CSTOPB;
1484
1485         /* parity must be enabled when CS7 to match 8-bits format */
1486         if ((termios->c_cflag & CSIZE) == CS7)
1487                 termios->c_cflag |= PARENB;
1488
1489         if ((termios->c_cflag & PARENB)) {
1490                 if (termios->c_cflag & CMSPAR) {
1491                         cr1 &= ~UARTCR1_PE;
1492                         if (termios->c_cflag & PARODD)
1493                                 cr3 |= UARTCR3_T8;
1494                         else
1495                                 cr3 &= ~UARTCR3_T8;
1496                 } else {
1497                         cr1 |= UARTCR1_PE;
1498                         if ((termios->c_cflag & CSIZE) == CS8)
1499                                 cr1 |= UARTCR1_M;
1500                         if (termios->c_cflag & PARODD)
1501                                 cr1 |= UARTCR1_PT;
1502                         else
1503                                 cr1 &= ~UARTCR1_PT;
1504                 }
1505         } else {
1506                 cr1 &= ~UARTCR1_PE;
1507         }
1508
1509         /* ask the core to calculate the divisor */
1510         baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1511
1512         /*
1513          * Need to update the Ring buffer length according to the selected
1514          * baud rate and restart Rx DMA path.
1515          *
1516          * Since timer function acqures sport->port.lock, need to stop before
1517          * acquring same lock because otherwise del_timer_sync() can deadlock.
1518          */
1519         if (old && sport->lpuart_dma_rx_use) {
1520                 del_timer_sync(&sport->lpuart_timer);
1521                 lpuart_dma_rx_free(&sport->port);
1522         }
1523
1524         spin_lock_irqsave(&sport->port.lock, flags);
1525
1526         sport->port.read_status_mask = 0;
1527         if (termios->c_iflag & INPCK)
1528                 sport->port.read_status_mask |= (UARTSR1_FE | UARTSR1_PE);
1529         if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1530                 sport->port.read_status_mask |= UARTSR1_FE;
1531
1532         /* characters to ignore */
1533         sport->port.ignore_status_mask = 0;
1534         if (termios->c_iflag & IGNPAR)
1535                 sport->port.ignore_status_mask |= UARTSR1_PE;
1536         if (termios->c_iflag & IGNBRK) {
1537                 sport->port.ignore_status_mask |= UARTSR1_FE;
1538                 /*
1539                  * if we're ignoring parity and break indicators,
1540                  * ignore overruns too (for real raw support).
1541                  */
1542                 if (termios->c_iflag & IGNPAR)
1543                         sport->port.ignore_status_mask |= UARTSR1_OR;
1544         }
1545
1546         /* update the per-port timeout */
1547         uart_update_timeout(port, termios->c_cflag, baud);
1548
1549         /* wait transmit engin complete */
1550         while (!(readb(sport->port.membase + UARTSR1) & UARTSR1_TC))
1551                 barrier();
1552
1553         /* disable transmit and receive */
1554         writeb(old_cr2 & ~(UARTCR2_TE | UARTCR2_RE),
1555                         sport->port.membase + UARTCR2);
1556
1557         sbr = sport->port.uartclk / (16 * baud);
1558         brfa = ((sport->port.uartclk - (16 * sbr * baud)) * 2) / baud;
1559         bdh &= ~UARTBDH_SBR_MASK;
1560         bdh |= (sbr >> 8) & 0x1F;
1561         cr4 &= ~UARTCR4_BRFA_MASK;
1562         brfa &= UARTCR4_BRFA_MASK;
1563         writeb(cr4 | brfa, sport->port.membase + UARTCR4);
1564         writeb(bdh, sport->port.membase + UARTBDH);
1565         writeb(sbr & 0xFF, sport->port.membase + UARTBDL);
1566         writeb(cr3, sport->port.membase + UARTCR3);
1567         writeb(cr1, sport->port.membase + UARTCR1);
1568         writeb(modem, sport->port.membase + UARTMODEM);
1569
1570         /* restore control register */
1571         writeb(old_cr2, sport->port.membase + UARTCR2);
1572
1573         if (old && sport->lpuart_dma_rx_use) {
1574                 if (!lpuart_start_rx_dma(sport))
1575                         rx_dma_timer_init(sport);
1576                 else
1577                         sport->lpuart_dma_rx_use = false;
1578         }
1579
1580         spin_unlock_irqrestore(&sport->port.lock, flags);
1581 }
1582
1583 static void
1584 lpuart32_serial_setbrg(struct lpuart_port *sport, unsigned int baudrate)
1585 {
1586         u32 sbr, osr, baud_diff, tmp_osr, tmp_sbr, tmp_diff, tmp;
1587         u32 clk = sport->port.uartclk;
1588
1589         /*
1590          * The idea is to use the best OSR (over-sampling rate) possible.
1591          * Note, OSR is typically hard-set to 16 in other LPUART instantiations.
1592          * Loop to find the best OSR value possible, one that generates minimum
1593          * baud_diff iterate through the rest of the supported values of OSR.
1594          *
1595          * Calculation Formula:
1596          *  Baud Rate = baud clock / ((OSR+1) × SBR)
1597          */
1598         baud_diff = baudrate;
1599         osr = 0;
1600         sbr = 0;
1601
1602         for (tmp_osr = 4; tmp_osr <= 32; tmp_osr++) {
1603                 /* calculate the temporary sbr value  */
1604                 tmp_sbr = (clk / (baudrate * tmp_osr));
1605                 if (tmp_sbr == 0)
1606                         tmp_sbr = 1;
1607
1608                 /*
1609                  * calculate the baud rate difference based on the temporary
1610                  * osr and sbr values
1611                  */
1612                 tmp_diff = clk / (tmp_osr * tmp_sbr) - baudrate;
1613
1614                 /* select best values between sbr and sbr+1 */
1615                 tmp = clk / (tmp_osr * (tmp_sbr + 1));
1616                 if (tmp_diff > (baudrate - tmp)) {
1617                         tmp_diff = baudrate - tmp;
1618                         tmp_sbr++;
1619                 }
1620
1621                 if (tmp_diff <= baud_diff) {
1622                         baud_diff = tmp_diff;
1623                         osr = tmp_osr;
1624                         sbr = tmp_sbr;
1625
1626                         if (!baud_diff)
1627                                 break;
1628                 }
1629         }
1630
1631         /* handle buadrate outside acceptable rate */
1632         if (baud_diff > ((baudrate / 100) * 3))
1633                 dev_warn(sport->port.dev,
1634                          "unacceptable baud rate difference of more than 3%%\n");
1635
1636         tmp = lpuart32_read(&sport->port, UARTBAUD);
1637
1638         if ((osr > 3) && (osr < 8))
1639                 tmp |= UARTBAUD_BOTHEDGE;
1640
1641         tmp &= ~(UARTBAUD_OSR_MASK << UARTBAUD_OSR_SHIFT);
1642         tmp |= (((osr-1) & UARTBAUD_OSR_MASK) << UARTBAUD_OSR_SHIFT);
1643
1644         tmp &= ~UARTBAUD_SBR_MASK;
1645         tmp |= sbr & UARTBAUD_SBR_MASK;
1646
1647         tmp &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE);
1648
1649         lpuart32_write(&sport->port, tmp, UARTBAUD);
1650 }
1651
1652 static void
1653 lpuart32_set_termios(struct uart_port *port, struct ktermios *termios,
1654                    struct ktermios *old)
1655 {
1656         struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1657         unsigned long flags;
1658         unsigned long ctrl, old_ctrl, bd, modem;
1659         unsigned int  baud;
1660         unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1661
1662         ctrl = old_ctrl = lpuart32_read(&sport->port, UARTCTRL);
1663         bd = lpuart32_read(&sport->port, UARTBAUD);
1664         modem = lpuart32_read(&sport->port, UARTMODIR);
1665         /*
1666          * only support CS8 and CS7, and for CS7 must enable PE.
1667          * supported mode:
1668          *  - (7,e/o,1)
1669          *  - (8,n,1)
1670          *  - (8,m/s,1)
1671          *  - (8,e/o,1)
1672          */
1673         while ((termios->c_cflag & CSIZE) != CS8 &&
1674                 (termios->c_cflag & CSIZE) != CS7) {
1675                 termios->c_cflag &= ~CSIZE;
1676                 termios->c_cflag |= old_csize;
1677                 old_csize = CS8;
1678         }
1679
1680         if ((termios->c_cflag & CSIZE) == CS8 ||
1681                 (termios->c_cflag & CSIZE) == CS7)
1682                 ctrl = old_ctrl & ~UARTCTRL_M;
1683
1684         if (termios->c_cflag & CMSPAR) {
1685                 if ((termios->c_cflag & CSIZE) != CS8) {
1686                         termios->c_cflag &= ~CSIZE;
1687                         termios->c_cflag |= CS8;
1688                 }
1689                 ctrl |= UARTCTRL_M;
1690         }
1691
1692         if (termios->c_cflag & CRTSCTS) {
1693                 modem |= (UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1694         } else {
1695                 termios->c_cflag &= ~CRTSCTS;
1696                 modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1697         }
1698
1699         if (termios->c_cflag & CSTOPB)
1700                 termios->c_cflag &= ~CSTOPB;
1701
1702         /* parity must be enabled when CS7 to match 8-bits format */
1703         if ((termios->c_cflag & CSIZE) == CS7)
1704                 termios->c_cflag |= PARENB;
1705
1706         if ((termios->c_cflag & PARENB)) {
1707                 if (termios->c_cflag & CMSPAR) {
1708                         ctrl &= ~UARTCTRL_PE;
1709                         ctrl |= UARTCTRL_M;
1710                 } else {
1711                         ctrl |= UARTCR1_PE;
1712                         if ((termios->c_cflag & CSIZE) == CS8)
1713                                 ctrl |= UARTCTRL_M;
1714                         if (termios->c_cflag & PARODD)
1715                                 ctrl |= UARTCTRL_PT;
1716                         else
1717                                 ctrl &= ~UARTCTRL_PT;
1718                 }
1719         } else {
1720                 ctrl &= ~UARTCTRL_PE;
1721         }
1722
1723         /* ask the core to calculate the divisor */
1724         baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 4);
1725
1726         spin_lock_irqsave(&sport->port.lock, flags);
1727
1728         sport->port.read_status_mask = 0;
1729         if (termios->c_iflag & INPCK)
1730                 sport->port.read_status_mask |= (UARTSTAT_FE | UARTSTAT_PE);
1731         if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1732                 sport->port.read_status_mask |= UARTSTAT_FE;
1733
1734         /* characters to ignore */
1735         sport->port.ignore_status_mask = 0;
1736         if (termios->c_iflag & IGNPAR)
1737                 sport->port.ignore_status_mask |= UARTSTAT_PE;
1738         if (termios->c_iflag & IGNBRK) {
1739                 sport->port.ignore_status_mask |= UARTSTAT_FE;
1740                 /*
1741                  * if we're ignoring parity and break indicators,
1742                  * ignore overruns too (for real raw support).
1743                  */
1744                 if (termios->c_iflag & IGNPAR)
1745                         sport->port.ignore_status_mask |= UARTSTAT_OR;
1746         }
1747
1748         /* update the per-port timeout */
1749         uart_update_timeout(port, termios->c_cflag, baud);
1750
1751         /* wait transmit engin complete */
1752         while (!(lpuart32_read(&sport->port, UARTSTAT) & UARTSTAT_TC))
1753                 barrier();
1754
1755         /* disable transmit and receive */
1756         lpuart32_write(&sport->port, old_ctrl & ~(UARTCTRL_TE | UARTCTRL_RE),
1757                        UARTCTRL);
1758
1759         lpuart32_serial_setbrg(sport, baud);
1760         lpuart32_write(&sport->port, modem, UARTMODIR);
1761         lpuart32_write(&sport->port, ctrl, UARTCTRL);
1762         /* restore control register */
1763
1764         spin_unlock_irqrestore(&sport->port.lock, flags);
1765 }
1766
1767 static const char *lpuart_type(struct uart_port *port)
1768 {
1769         return "FSL_LPUART";
1770 }
1771
1772 static void lpuart_release_port(struct uart_port *port)
1773 {
1774         /* nothing to do */
1775 }
1776
1777 static int lpuart_request_port(struct uart_port *port)
1778 {
1779         return  0;
1780 }
1781
1782 /* configure/autoconfigure the port */
1783 static void lpuart_config_port(struct uart_port *port, int flags)
1784 {
1785         if (flags & UART_CONFIG_TYPE)
1786                 port->type = PORT_LPUART;
1787 }
1788
1789 static int lpuart_verify_port(struct uart_port *port, struct serial_struct *ser)
1790 {
1791         int ret = 0;
1792
1793         if (ser->type != PORT_UNKNOWN && ser->type != PORT_LPUART)
1794                 ret = -EINVAL;
1795         if (port->irq != ser->irq)
1796                 ret = -EINVAL;
1797         if (ser->io_type != UPIO_MEM)
1798                 ret = -EINVAL;
1799         if (port->uartclk / 16 != ser->baud_base)
1800                 ret = -EINVAL;
1801         if (port->iobase != ser->port)
1802                 ret = -EINVAL;
1803         if (ser->hub6 != 0)
1804                 ret = -EINVAL;
1805         return ret;
1806 }
1807
1808 static const struct uart_ops lpuart_pops = {
1809         .tx_empty       = lpuart_tx_empty,
1810         .set_mctrl      = lpuart_set_mctrl,
1811         .get_mctrl      = lpuart_get_mctrl,
1812         .stop_tx        = lpuart_stop_tx,
1813         .start_tx       = lpuart_start_tx,
1814         .stop_rx        = lpuart_stop_rx,
1815         .break_ctl      = lpuart_break_ctl,
1816         .startup        = lpuart_startup,
1817         .shutdown       = lpuart_shutdown,
1818         .set_termios    = lpuart_set_termios,
1819         .type           = lpuart_type,
1820         .request_port   = lpuart_request_port,
1821         .release_port   = lpuart_release_port,
1822         .config_port    = lpuart_config_port,
1823         .verify_port    = lpuart_verify_port,
1824         .flush_buffer   = lpuart_flush_buffer,
1825 #if defined(CONFIG_CONSOLE_POLL)
1826         .poll_init      = lpuart_poll_init,
1827         .poll_get_char  = lpuart_poll_get_char,
1828         .poll_put_char  = lpuart_poll_put_char,
1829 #endif
1830 };
1831
1832 static const struct uart_ops lpuart32_pops = {
1833         .tx_empty       = lpuart32_tx_empty,
1834         .set_mctrl      = lpuart32_set_mctrl,
1835         .get_mctrl      = lpuart32_get_mctrl,
1836         .stop_tx        = lpuart32_stop_tx,
1837         .start_tx       = lpuart32_start_tx,
1838         .stop_rx        = lpuart32_stop_rx,
1839         .break_ctl      = lpuart32_break_ctl,
1840         .startup        = lpuart32_startup,
1841         .shutdown       = lpuart32_shutdown,
1842         .set_termios    = lpuart32_set_termios,
1843         .type           = lpuart_type,
1844         .request_port   = lpuart_request_port,
1845         .release_port   = lpuart_release_port,
1846         .config_port    = lpuart_config_port,
1847         .verify_port    = lpuart_verify_port,
1848         .flush_buffer   = lpuart_flush_buffer,
1849 #if defined(CONFIG_CONSOLE_POLL)
1850         .poll_init      = lpuart32_poll_init,
1851         .poll_get_char  = lpuart32_poll_get_char,
1852         .poll_put_char  = lpuart32_poll_put_char,
1853 #endif
1854 };
1855
1856 static struct lpuart_port *lpuart_ports[UART_NR];
1857
1858 #ifdef CONFIG_SERIAL_FSL_LPUART_CONSOLE
1859 static void lpuart_console_putchar(struct uart_port *port, int ch)
1860 {
1861         while (!(readb(port->membase + UARTSR1) & UARTSR1_TDRE))
1862                 barrier();
1863
1864         writeb(ch, port->membase + UARTDR);
1865 }
1866
1867 static void lpuart32_console_putchar(struct uart_port *port, int ch)
1868 {
1869         while (!(lpuart32_read(port, UARTSTAT) & UARTSTAT_TDRE))
1870                 barrier();
1871
1872         lpuart32_write(port, ch, UARTDATA);
1873 }
1874
1875 static void
1876 lpuart_console_write(struct console *co, const char *s, unsigned int count)
1877 {
1878         struct lpuart_port *sport = lpuart_ports[co->index];
1879         unsigned char  old_cr2, cr2;
1880         unsigned long flags;
1881         int locked = 1;
1882
1883         if (sport->port.sysrq || oops_in_progress)
1884                 locked = spin_trylock_irqsave(&sport->port.lock, flags);
1885         else
1886                 spin_lock_irqsave(&sport->port.lock, flags);
1887
1888         /* first save CR2 and then disable interrupts */
1889         cr2 = old_cr2 = readb(sport->port.membase + UARTCR2);
1890         cr2 |= (UARTCR2_TE |  UARTCR2_RE);
1891         cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
1892         writeb(cr2, sport->port.membase + UARTCR2);
1893
1894         uart_console_write(&sport->port, s, count, lpuart_console_putchar);
1895
1896         /* wait for transmitter finish complete and restore CR2 */
1897         while (!(readb(sport->port.membase + UARTSR1) & UARTSR1_TC))
1898                 barrier();
1899
1900         writeb(old_cr2, sport->port.membase + UARTCR2);
1901
1902         if (locked)
1903                 spin_unlock_irqrestore(&sport->port.lock, flags);
1904 }
1905
1906 static void
1907 lpuart32_console_write(struct console *co, const char *s, unsigned int count)
1908 {
1909         struct lpuart_port *sport = lpuart_ports[co->index];
1910         unsigned long  old_cr, cr;
1911         unsigned long flags;
1912         int locked = 1;
1913
1914         if (sport->port.sysrq || oops_in_progress)
1915                 locked = spin_trylock_irqsave(&sport->port.lock, flags);
1916         else
1917                 spin_lock_irqsave(&sport->port.lock, flags);
1918
1919         /* first save CR2 and then disable interrupts */
1920         cr = old_cr = lpuart32_read(&sport->port, UARTCTRL);
1921         cr |= (UARTCTRL_TE |  UARTCTRL_RE);
1922         cr &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
1923         lpuart32_write(&sport->port, cr, UARTCTRL);
1924
1925         uart_console_write(&sport->port, s, count, lpuart32_console_putchar);
1926
1927         /* wait for transmitter finish complete and restore CR2 */
1928         while (!(lpuart32_read(&sport->port, UARTSTAT) & UARTSTAT_TC))
1929                 barrier();
1930
1931         lpuart32_write(&sport->port, old_cr, UARTCTRL);
1932
1933         if (locked)
1934                 spin_unlock_irqrestore(&sport->port.lock, flags);
1935 }
1936
1937 /*
1938  * if the port was already initialised (eg, by a boot loader),
1939  * try to determine the current setup.
1940  */
1941 static void __init
1942 lpuart_console_get_options(struct lpuart_port *sport, int *baud,
1943                            int *parity, int *bits)
1944 {
1945         unsigned char cr, bdh, bdl, brfa;
1946         unsigned int sbr, uartclk, baud_raw;
1947
1948         cr = readb(sport->port.membase + UARTCR2);
1949         cr &= UARTCR2_TE | UARTCR2_RE;
1950         if (!cr)
1951                 return;
1952
1953         /* ok, the port was enabled */
1954
1955         cr = readb(sport->port.membase + UARTCR1);
1956
1957         *parity = 'n';
1958         if (cr & UARTCR1_PE) {
1959                 if (cr & UARTCR1_PT)
1960                         *parity = 'o';
1961                 else
1962                         *parity = 'e';
1963         }
1964
1965         if (cr & UARTCR1_M)
1966                 *bits = 9;
1967         else
1968                 *bits = 8;
1969
1970         bdh = readb(sport->port.membase + UARTBDH);
1971         bdh &= UARTBDH_SBR_MASK;
1972         bdl = readb(sport->port.membase + UARTBDL);
1973         sbr = bdh;
1974         sbr <<= 8;
1975         sbr |= bdl;
1976         brfa = readb(sport->port.membase + UARTCR4);
1977         brfa &= UARTCR4_BRFA_MASK;
1978
1979         uartclk = clk_get_rate(sport->clk);
1980         /*
1981          * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
1982          */
1983         baud_raw = uartclk / (16 * (sbr + brfa / 32));
1984
1985         if (*baud != baud_raw)
1986                 printk(KERN_INFO "Serial: Console lpuart rounded baud rate"
1987                                 "from %d to %d\n", baud_raw, *baud);
1988 }
1989
1990 static void __init
1991 lpuart32_console_get_options(struct lpuart_port *sport, int *baud,
1992                            int *parity, int *bits)
1993 {
1994         unsigned long cr, bd;
1995         unsigned int sbr, uartclk, baud_raw;
1996
1997         cr = lpuart32_read(&sport->port, UARTCTRL);
1998         cr &= UARTCTRL_TE | UARTCTRL_RE;
1999         if (!cr)
2000                 return;
2001
2002         /* ok, the port was enabled */
2003
2004         cr = lpuart32_read(&sport->port, UARTCTRL);
2005
2006         *parity = 'n';
2007         if (cr & UARTCTRL_PE) {
2008                 if (cr & UARTCTRL_PT)
2009                         *parity = 'o';
2010                 else
2011                         *parity = 'e';
2012         }
2013
2014         if (cr & UARTCTRL_M)
2015                 *bits = 9;
2016         else
2017                 *bits = 8;
2018
2019         bd = lpuart32_read(&sport->port, UARTBAUD);
2020         bd &= UARTBAUD_SBR_MASK;
2021         if (!bd)
2022                 return;
2023
2024         sbr = bd;
2025         uartclk = clk_get_rate(sport->clk);
2026         /*
2027          * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
2028          */
2029         baud_raw = uartclk / (16 * sbr);
2030
2031         if (*baud != baud_raw)
2032                 printk(KERN_INFO "Serial: Console lpuart rounded baud rate"
2033                                 "from %d to %d\n", baud_raw, *baud);
2034 }
2035
2036 static int __init lpuart_console_setup(struct console *co, char *options)
2037 {
2038         struct lpuart_port *sport;
2039         int baud = 115200;
2040         int bits = 8;
2041         int parity = 'n';
2042         int flow = 'n';
2043
2044         /*
2045          * check whether an invalid uart number has been specified, and
2046          * if so, search for the first available port that does have
2047          * console support.
2048          */
2049         if (co->index == -1 || co->index >= ARRAY_SIZE(lpuart_ports))
2050                 co->index = 0;
2051
2052         sport = lpuart_ports[co->index];
2053         if (sport == NULL)
2054                 return -ENODEV;
2055
2056         if (options)
2057                 uart_parse_options(options, &baud, &parity, &bits, &flow);
2058         else
2059                 if (lpuart_is_32(sport))
2060                         lpuart32_console_get_options(sport, &baud, &parity, &bits);
2061                 else
2062                         lpuart_console_get_options(sport, &baud, &parity, &bits);
2063
2064         if (lpuart_is_32(sport))
2065                 lpuart32_setup_watermark(sport);
2066         else
2067                 lpuart_setup_watermark(sport);
2068
2069         return uart_set_options(&sport->port, co, baud, parity, bits, flow);
2070 }
2071
2072 static struct uart_driver lpuart_reg;
2073 static struct console lpuart_console = {
2074         .name           = DEV_NAME,
2075         .write          = lpuart_console_write,
2076         .device         = uart_console_device,
2077         .setup          = lpuart_console_setup,
2078         .flags          = CON_PRINTBUFFER,
2079         .index          = -1,
2080         .data           = &lpuart_reg,
2081 };
2082
2083 static struct console lpuart32_console = {
2084         .name           = DEV_NAME,
2085         .write          = lpuart32_console_write,
2086         .device         = uart_console_device,
2087         .setup          = lpuart_console_setup,
2088         .flags          = CON_PRINTBUFFER,
2089         .index          = -1,
2090         .data           = &lpuart_reg,
2091 };
2092
2093 static void lpuart_early_write(struct console *con, const char *s, unsigned n)
2094 {
2095         struct earlycon_device *dev = con->data;
2096
2097         uart_console_write(&dev->port, s, n, lpuart_console_putchar);
2098 }
2099
2100 static void lpuart32_early_write(struct console *con, const char *s, unsigned n)
2101 {
2102         struct earlycon_device *dev = con->data;
2103
2104         uart_console_write(&dev->port, s, n, lpuart32_console_putchar);
2105 }
2106
2107 static int __init lpuart_early_console_setup(struct earlycon_device *device,
2108                                           const char *opt)
2109 {
2110         if (!device->port.membase)
2111                 return -ENODEV;
2112
2113         device->con->write = lpuart_early_write;
2114         return 0;
2115 }
2116
2117 static int __init lpuart32_early_console_setup(struct earlycon_device *device,
2118                                           const char *opt)
2119 {
2120         if (!device->port.membase)
2121                 return -ENODEV;
2122
2123         device->port.iotype = UPIO_MEM32BE;
2124         device->con->write = lpuart32_early_write;
2125         return 0;
2126 }
2127
2128 static int __init lpuart32_imx_early_console_setup(struct earlycon_device *device,
2129                                                    const char *opt)
2130 {
2131         if (!device->port.membase)
2132                 return -ENODEV;
2133
2134         device->port.iotype = UPIO_MEM32;
2135         device->port.membase += IMX_REG_OFF;
2136         device->con->write = lpuart32_early_write;
2137
2138         return 0;
2139 }
2140 OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup);
2141 OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup);
2142 OF_EARLYCON_DECLARE(lpuart32, "fsl,imx7ulp-lpuart", lpuart32_imx_early_console_setup);
2143 EARLYCON_DECLARE(lpuart, lpuart_early_console_setup);
2144 EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup);
2145
2146 #define LPUART_CONSOLE  (&lpuart_console)
2147 #define LPUART32_CONSOLE        (&lpuart32_console)
2148 #else
2149 #define LPUART_CONSOLE  NULL
2150 #define LPUART32_CONSOLE        NULL
2151 #endif
2152
2153 static struct uart_driver lpuart_reg = {
2154         .owner          = THIS_MODULE,
2155         .driver_name    = DRIVER_NAME,
2156         .dev_name       = DEV_NAME,
2157         .nr             = ARRAY_SIZE(lpuart_ports),
2158         .cons           = LPUART_CONSOLE,
2159 };
2160
2161 static int lpuart_probe(struct platform_device *pdev)
2162 {
2163         const struct of_device_id *of_id = of_match_device(lpuart_dt_ids,
2164                                                            &pdev->dev);
2165         const struct lpuart_soc_data *sdata = of_id->data;
2166         struct device_node *np = pdev->dev.of_node;
2167         struct lpuart_port *sport;
2168         struct resource *res;
2169         int ret;
2170
2171         sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
2172         if (!sport)
2173                 return -ENOMEM;
2174
2175         pdev->dev.coherent_dma_mask = 0;
2176
2177         ret = of_alias_get_id(np, "serial");
2178         if (ret < 0) {
2179                 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
2180                 return ret;
2181         }
2182         if (ret >= ARRAY_SIZE(lpuart_ports)) {
2183                 dev_err(&pdev->dev, "serial%d out of range\n", ret);
2184                 return -EINVAL;
2185         }
2186         sport->port.line = ret;
2187         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2188         sport->port.membase = devm_ioremap_resource(&pdev->dev, res);
2189         if (IS_ERR(sport->port.membase))
2190                 return PTR_ERR(sport->port.membase);
2191
2192         sport->port.membase += sdata->reg_off;
2193         sport->port.mapbase = res->start + sdata->reg_off;
2194         sport->port.dev = &pdev->dev;
2195         sport->port.type = PORT_LPUART;
2196         ret = platform_get_irq(pdev, 0);
2197         if (ret < 0) {
2198                 dev_err(&pdev->dev, "cannot obtain irq\n");
2199                 return ret;
2200         }
2201         sport->port.irq = ret;
2202         sport->port.iotype = sdata->iotype;
2203         if (lpuart_is_32(sport))
2204                 sport->port.ops = &lpuart32_pops;
2205         else
2206                 sport->port.ops = &lpuart_pops;
2207         sport->port.flags = UPF_BOOT_AUTOCONF;
2208
2209         sport->port.rs485_config = lpuart_config_rs485;
2210
2211         sport->clk = devm_clk_get(&pdev->dev, "ipg");
2212         if (IS_ERR(sport->clk)) {
2213                 ret = PTR_ERR(sport->clk);
2214                 dev_err(&pdev->dev, "failed to get uart clk: %d\n", ret);
2215                 return ret;
2216         }
2217
2218         ret = clk_prepare_enable(sport->clk);
2219         if (ret) {
2220                 dev_err(&pdev->dev, "failed to enable uart clk: %d\n", ret);
2221                 return ret;
2222         }
2223
2224         sport->port.uartclk = clk_get_rate(sport->clk);
2225
2226         lpuart_ports[sport->port.line] = sport;
2227
2228         platform_set_drvdata(pdev, &sport->port);
2229
2230         if (lpuart_is_32(sport)) {
2231                 lpuart_reg.cons = LPUART32_CONSOLE;
2232                 ret = devm_request_irq(&pdev->dev, sport->port.irq, lpuart32_int, 0,
2233                                         DRIVER_NAME, sport);
2234         } else {
2235                 lpuart_reg.cons = LPUART_CONSOLE;
2236                 ret = devm_request_irq(&pdev->dev, sport->port.irq, lpuart_int, 0,
2237                                         DRIVER_NAME, sport);
2238         }
2239
2240         if (ret)
2241                 goto failed_irq_request;
2242
2243         ret = uart_add_one_port(&lpuart_reg, &sport->port);
2244         if (ret)
2245                 goto failed_attach_port;
2246
2247         sport->dma_tx_chan = dma_request_slave_channel(sport->port.dev, "tx");
2248         if (!sport->dma_tx_chan)
2249                 dev_info(sport->port.dev, "DMA tx channel request failed, "
2250                                 "operating without tx DMA\n");
2251
2252         sport->dma_rx_chan = dma_request_slave_channel(sport->port.dev, "rx");
2253         if (!sport->dma_rx_chan)
2254                 dev_info(sport->port.dev, "DMA rx channel request failed, "
2255                                 "operating without rx DMA\n");
2256
2257         if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time")) {
2258                 sport->port.rs485.flags |= SER_RS485_ENABLED;
2259                 sport->port.rs485.flags |= SER_RS485_RTS_ON_SEND;
2260                 writeb(UARTMODEM_TXRTSE, sport->port.membase + UARTMODEM);
2261         }
2262
2263         return 0;
2264
2265 failed_attach_port:
2266 failed_irq_request:
2267         clk_disable_unprepare(sport->clk);
2268         return ret;
2269 }
2270
2271 static int lpuart_remove(struct platform_device *pdev)
2272 {
2273         struct lpuart_port *sport = platform_get_drvdata(pdev);
2274
2275         uart_remove_one_port(&lpuart_reg, &sport->port);
2276
2277         clk_disable_unprepare(sport->clk);
2278
2279         if (sport->dma_tx_chan)
2280                 dma_release_channel(sport->dma_tx_chan);
2281
2282         if (sport->dma_rx_chan)
2283                 dma_release_channel(sport->dma_rx_chan);
2284
2285         return 0;
2286 }
2287
2288 #ifdef CONFIG_PM_SLEEP
2289 static int lpuart_suspend(struct device *dev)
2290 {
2291         struct lpuart_port *sport = dev_get_drvdata(dev);
2292         unsigned long temp;
2293         bool irq_wake;
2294
2295         if (lpuart_is_32(sport)) {
2296                 /* disable Rx/Tx and interrupts */
2297                 temp = lpuart32_read(&sport->port, UARTCTRL);
2298                 temp &= ~(UARTCTRL_TE | UARTCTRL_TIE | UARTCTRL_TCIE);
2299                 lpuart32_write(&sport->port, temp, UARTCTRL);
2300         } else {
2301                 /* disable Rx/Tx and interrupts */
2302                 temp = readb(sport->port.membase + UARTCR2);
2303                 temp &= ~(UARTCR2_TE | UARTCR2_TIE | UARTCR2_TCIE);
2304                 writeb(temp, sport->port.membase + UARTCR2);
2305         }
2306
2307         uart_suspend_port(&lpuart_reg, &sport->port);
2308
2309         /* uart_suspend_port() might set wakeup flag */
2310         irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq));
2311
2312         if (sport->lpuart_dma_rx_use) {
2313                 /*
2314                  * EDMA driver during suspend will forcefully release any
2315                  * non-idle DMA channels. If port wakeup is enabled or if port
2316                  * is console port or 'no_console_suspend' is set the Rx DMA
2317                  * cannot resume as as expected, hence gracefully release the
2318                  * Rx DMA path before suspend and start Rx DMA path on resume.
2319                  */
2320                 if (irq_wake) {
2321                         del_timer_sync(&sport->lpuart_timer);
2322                         lpuart_dma_rx_free(&sport->port);
2323                 }
2324
2325                 /* Disable Rx DMA to use UART port as wakeup source */
2326                 writeb(readb(sport->port.membase + UARTCR5) & ~UARTCR5_RDMAS,
2327                                         sport->port.membase + UARTCR5);
2328         }
2329
2330         if (sport->lpuart_dma_tx_use) {
2331                 sport->dma_tx_in_progress = false;
2332                 dmaengine_terminate_all(sport->dma_tx_chan);
2333         }
2334
2335         if (sport->port.suspended && !irq_wake)
2336                 clk_disable_unprepare(sport->clk);
2337
2338         return 0;
2339 }
2340
2341 static int lpuart_resume(struct device *dev)
2342 {
2343         struct lpuart_port *sport = dev_get_drvdata(dev);
2344         bool irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq));
2345         unsigned long temp;
2346
2347         if (sport->port.suspended && !irq_wake)
2348                 clk_prepare_enable(sport->clk);
2349
2350         if (lpuart_is_32(sport)) {
2351                 lpuart32_setup_watermark(sport);
2352                 temp = lpuart32_read(&sport->port, UARTCTRL);
2353                 temp |= (UARTCTRL_RIE | UARTCTRL_TIE | UARTCTRL_RE |
2354                          UARTCTRL_TE | UARTCTRL_ILIE);
2355                 lpuart32_write(&sport->port, temp, UARTCTRL);
2356         } else {
2357                 lpuart_setup_watermark(sport);
2358                 temp = readb(sport->port.membase + UARTCR2);
2359                 temp |= (UARTCR2_RIE | UARTCR2_TIE | UARTCR2_RE | UARTCR2_TE);
2360                 writeb(temp, sport->port.membase + UARTCR2);
2361         }
2362
2363         if (sport->lpuart_dma_rx_use) {
2364                 if (irq_wake) {
2365                         if (!lpuart_start_rx_dma(sport))
2366                                 rx_dma_timer_init(sport);
2367                         else
2368                                 sport->lpuart_dma_rx_use = false;
2369                 }
2370         }
2371
2372         if (sport->dma_tx_chan && !lpuart_dma_tx_request(&sport->port)) {
2373                         init_waitqueue_head(&sport->dma_wait);
2374                         sport->lpuart_dma_tx_use = true;
2375                         writeb(readb(sport->port.membase + UARTCR5) |
2376                                 UARTCR5_TDMAS, sport->port.membase + UARTCR5);
2377         } else {
2378                 sport->lpuart_dma_tx_use = false;
2379         }
2380
2381         uart_resume_port(&lpuart_reg, &sport->port);
2382
2383         return 0;
2384 }
2385 #endif
2386
2387 static SIMPLE_DEV_PM_OPS(lpuart_pm_ops, lpuart_suspend, lpuart_resume);
2388
2389 static struct platform_driver lpuart_driver = {
2390         .probe          = lpuart_probe,
2391         .remove         = lpuart_remove,
2392         .driver         = {
2393                 .name   = "fsl-lpuart",
2394                 .of_match_table = lpuart_dt_ids,
2395                 .pm     = &lpuart_pm_ops,
2396         },
2397 };
2398
2399 static int __init lpuart_serial_init(void)
2400 {
2401         int ret = uart_register_driver(&lpuart_reg);
2402
2403         if (ret)
2404                 return ret;
2405
2406         ret = platform_driver_register(&lpuart_driver);
2407         if (ret)
2408                 uart_unregister_driver(&lpuart_reg);
2409
2410         return ret;
2411 }
2412
2413 static void __exit lpuart_serial_exit(void)
2414 {
2415         platform_driver_unregister(&lpuart_driver);
2416         uart_unregister_driver(&lpuart_reg);
2417 }
2418
2419 module_init(lpuart_serial_init);
2420 module_exit(lpuart_serial_exit);
2421
2422 MODULE_DESCRIPTION("Freescale lpuart serial port driver");
2423 MODULE_LICENSE("GPL v2");