root/drivers/spi/spi-fsl-dspi.c

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DEFINITIONS

This source file includes following definitions.
  1. dspi_pop_tx
  2. dspi_pop_tx_pushr
  3. dspi_push_rx
  4. dspi_tx_dma_callback
  5. dspi_rx_dma_callback
  6. dspi_next_xfer_dma_submit
  7. dspi_dma_xfer
  8. dspi_request_dma
  9. dspi_release_dma
  10. hz_to_spi_baud
  11. ns_delay_scale
  12. fifo_write
  13. cmd_fifo_write
  14. tx_fifo_write
  15. dspi_tcfq_write
  16. fifo_read
  17. dspi_tcfq_read
  18. dspi_eoq_write
  19. dspi_eoq_read
  20. dspi_rxtx
  21. dspi_poll
  22. dspi_interrupt
  23. dspi_transfer_one_message
  24. dspi_setup
  25. dspi_cleanup
  26. dspi_suspend
  27. dspi_resume
  28. dspi_init
  29. dspi_probe
  30. dspi_remove

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // Copyright 2013 Freescale Semiconductor, Inc.
   4 //
   5 // Freescale DSPI driver
   6 // This file contains a driver for the Freescale DSPI
   7 
   8 #include <linux/clk.h>
   9 #include <linux/delay.h>
  10 #include <linux/dmaengine.h>
  11 #include <linux/dma-mapping.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/of_device.h>
  16 #include <linux/pinctrl/consumer.h>
  17 #include <linux/regmap.h>
  18 #include <linux/spi/spi.h>
  19 #include <linux/spi/spi-fsl-dspi.h>
  20 
  21 #define DRIVER_NAME                     "fsl-dspi"
  22 
  23 #ifdef CONFIG_M5441x
  24 #define DSPI_FIFO_SIZE                  16
  25 #else
  26 #define DSPI_FIFO_SIZE                  4
  27 #endif
  28 #define DSPI_DMA_BUFSIZE                (DSPI_FIFO_SIZE * 1024)
  29 
  30 #define SPI_MCR                         0x00
  31 #define SPI_MCR_MASTER                  BIT(31)
  32 #define SPI_MCR_PCSIS                   (0x3F << 16)
  33 #define SPI_MCR_CLR_TXF                 BIT(11)
  34 #define SPI_MCR_CLR_RXF                 BIT(10)
  35 #define SPI_MCR_XSPI                    BIT(3)
  36 
  37 #define SPI_TCR                         0x08
  38 #define SPI_TCR_GET_TCNT(x)             (((x) & GENMASK(31, 16)) >> 16)
  39 
  40 #define SPI_CTAR(x)                     (0x0c + (((x) & GENMASK(1, 0)) * 4))
  41 #define SPI_CTAR_FMSZ(x)                (((x) << 27) & GENMASK(30, 27))
  42 #define SPI_CTAR_CPOL                   BIT(26)
  43 #define SPI_CTAR_CPHA                   BIT(25)
  44 #define SPI_CTAR_LSBFE                  BIT(24)
  45 #define SPI_CTAR_PCSSCK(x)              (((x) << 22) & GENMASK(23, 22))
  46 #define SPI_CTAR_PASC(x)                (((x) << 20) & GENMASK(21, 20))
  47 #define SPI_CTAR_PDT(x)                 (((x) << 18) & GENMASK(19, 18))
  48 #define SPI_CTAR_PBR(x)                 (((x) << 16) & GENMASK(17, 16))
  49 #define SPI_CTAR_CSSCK(x)               (((x) << 12) & GENMASK(15, 12))
  50 #define SPI_CTAR_ASC(x)                 (((x) << 8) & GENMASK(11, 8))
  51 #define SPI_CTAR_DT(x)                  (((x) << 4) & GENMASK(7, 4))
  52 #define SPI_CTAR_BR(x)                  ((x) & GENMASK(3, 0))
  53 #define SPI_CTAR_SCALE_BITS             0xf
  54 
  55 #define SPI_CTAR0_SLAVE                 0x0c
  56 
  57 #define SPI_SR                          0x2c
  58 #define SPI_SR_TCFQF                    BIT(31)
  59 #define SPI_SR_EOQF                     BIT(28)
  60 #define SPI_SR_TFUF                     BIT(27)
  61 #define SPI_SR_TFFF                     BIT(25)
  62 #define SPI_SR_CMDTCF                   BIT(23)
  63 #define SPI_SR_SPEF                     BIT(21)
  64 #define SPI_SR_RFOF                     BIT(19)
  65 #define SPI_SR_TFIWF                    BIT(18)
  66 #define SPI_SR_RFDF                     BIT(17)
  67 #define SPI_SR_CMDFFF                   BIT(16)
  68 #define SPI_SR_CLEAR                    (SPI_SR_TCFQF | SPI_SR_EOQF | \
  69                                         SPI_SR_TFUF | SPI_SR_TFFF | \
  70                                         SPI_SR_CMDTCF | SPI_SR_SPEF | \
  71                                         SPI_SR_RFOF | SPI_SR_TFIWF | \
  72                                         SPI_SR_RFDF | SPI_SR_CMDFFF)
  73 
  74 #define SPI_RSER_TFFFE                  BIT(25)
  75 #define SPI_RSER_TFFFD                  BIT(24)
  76 #define SPI_RSER_RFDFE                  BIT(17)
  77 #define SPI_RSER_RFDFD                  BIT(16)
  78 
  79 #define SPI_RSER                        0x30
  80 #define SPI_RSER_TCFQE                  BIT(31)
  81 #define SPI_RSER_EOQFE                  BIT(28)
  82 
  83 #define SPI_PUSHR                       0x34
  84 #define SPI_PUSHR_CMD_CONT              BIT(15)
  85 #define SPI_PUSHR_CMD_CTAS(x)           (((x) << 12 & GENMASK(14, 12)))
  86 #define SPI_PUSHR_CMD_EOQ               BIT(11)
  87 #define SPI_PUSHR_CMD_CTCNT             BIT(10)
  88 #define SPI_PUSHR_CMD_PCS(x)            (BIT(x) & GENMASK(5, 0))
  89 
  90 #define SPI_PUSHR_SLAVE                 0x34
  91 
  92 #define SPI_POPR                        0x38
  93 
  94 #define SPI_TXFR0                       0x3c
  95 #define SPI_TXFR1                       0x40
  96 #define SPI_TXFR2                       0x44
  97 #define SPI_TXFR3                       0x48
  98 #define SPI_RXFR0                       0x7c
  99 #define SPI_RXFR1                       0x80
 100 #define SPI_RXFR2                       0x84
 101 #define SPI_RXFR3                       0x88
 102 
 103 #define SPI_CTARE(x)                    (0x11c + (((x) & GENMASK(1, 0)) * 4))
 104 #define SPI_CTARE_FMSZE(x)              (((x) & 0x1) << 16)
 105 #define SPI_CTARE_DTCP(x)               ((x) & 0x7ff)
 106 
 107 #define SPI_SREX                        0x13c
 108 
 109 #define SPI_FRAME_BITS(bits)            SPI_CTAR_FMSZ((bits) - 1)
 110 #define SPI_FRAME_EBITS(bits)           SPI_CTARE_FMSZE(((bits) - 1) >> 4)
 111 
 112 /* Register offsets for regmap_pushr */
 113 #define PUSHR_CMD                       0x0
 114 #define PUSHR_TX                        0x2
 115 
 116 #define DMA_COMPLETION_TIMEOUT          msecs_to_jiffies(3000)
 117 
 118 struct chip_data {
 119         u32                     ctar_val;
 120         u16                     void_write_data;
 121 };
 122 
 123 enum dspi_trans_mode {
 124         DSPI_EOQ_MODE = 0,
 125         DSPI_TCFQ_MODE,
 126         DSPI_DMA_MODE,
 127 };
 128 
 129 struct fsl_dspi_devtype_data {
 130         enum dspi_trans_mode    trans_mode;
 131         u8                      max_clock_factor;
 132         bool                    xspi_mode;
 133 };
 134 
 135 static const struct fsl_dspi_devtype_data vf610_data = {
 136         .trans_mode             = DSPI_DMA_MODE,
 137         .max_clock_factor       = 2,
 138 };
 139 
 140 static const struct fsl_dspi_devtype_data ls1021a_v1_data = {
 141         .trans_mode             = DSPI_TCFQ_MODE,
 142         .max_clock_factor       = 8,
 143         .xspi_mode              = true,
 144 };
 145 
 146 static const struct fsl_dspi_devtype_data ls2085a_data = {
 147         .trans_mode             = DSPI_TCFQ_MODE,
 148         .max_clock_factor       = 8,
 149 };
 150 
 151 static const struct fsl_dspi_devtype_data coldfire_data = {
 152         .trans_mode             = DSPI_EOQ_MODE,
 153         .max_clock_factor       = 8,
 154 };
 155 
 156 struct fsl_dspi_dma {
 157         /* Length of transfer in words of DSPI_FIFO_SIZE */
 158         u32                                     curr_xfer_len;
 159 
 160         u32                                     *tx_dma_buf;
 161         struct dma_chan                         *chan_tx;
 162         dma_addr_t                              tx_dma_phys;
 163         struct completion                       cmd_tx_complete;
 164         struct dma_async_tx_descriptor          *tx_desc;
 165 
 166         u32                                     *rx_dma_buf;
 167         struct dma_chan                         *chan_rx;
 168         dma_addr_t                              rx_dma_phys;
 169         struct completion                       cmd_rx_complete;
 170         struct dma_async_tx_descriptor          *rx_desc;
 171 };
 172 
 173 struct fsl_dspi {
 174         struct spi_controller                   *ctlr;
 175         struct platform_device                  *pdev;
 176 
 177         struct regmap                           *regmap;
 178         struct regmap                           *regmap_pushr;
 179         int                                     irq;
 180         struct clk                              *clk;
 181 
 182         struct spi_transfer                     *cur_transfer;
 183         struct spi_message                      *cur_msg;
 184         struct chip_data                        *cur_chip;
 185         size_t                                  len;
 186         const void                              *tx;
 187         void                                    *rx;
 188         void                                    *rx_end;
 189         u16                                     void_write_data;
 190         u16                                     tx_cmd;
 191         u8                                      bits_per_word;
 192         u8                                      bytes_per_word;
 193         const struct fsl_dspi_devtype_data      *devtype_data;
 194 
 195         struct completion                       xfer_done;
 196 
 197         struct fsl_dspi_dma                     *dma;
 198 };
 199 
 200 static u32 dspi_pop_tx(struct fsl_dspi *dspi)
 201 {
 202         u32 txdata = 0;
 203 
 204         if (dspi->tx) {
 205                 if (dspi->bytes_per_word == 1)
 206                         txdata = *(u8 *)dspi->tx;
 207                 else if (dspi->bytes_per_word == 2)
 208                         txdata = *(u16 *)dspi->tx;
 209                 else  /* dspi->bytes_per_word == 4 */
 210                         txdata = *(u32 *)dspi->tx;
 211                 dspi->tx += dspi->bytes_per_word;
 212         }
 213         dspi->len -= dspi->bytes_per_word;
 214         return txdata;
 215 }
 216 
 217 static u32 dspi_pop_tx_pushr(struct fsl_dspi *dspi)
 218 {
 219         u16 cmd = dspi->tx_cmd, data = dspi_pop_tx(dspi);
 220 
 221         if (spi_controller_is_slave(dspi->ctlr))
 222                 return data;
 223 
 224         if (dspi->len > 0)
 225                 cmd |= SPI_PUSHR_CMD_CONT;
 226         return cmd << 16 | data;
 227 }
 228 
 229 static void dspi_push_rx(struct fsl_dspi *dspi, u32 rxdata)
 230 {
 231         if (!dspi->rx)
 232                 return;
 233 
 234         /* Mask off undefined bits */
 235         rxdata &= (1 << dspi->bits_per_word) - 1;
 236 
 237         if (dspi->bytes_per_word == 1)
 238                 *(u8 *)dspi->rx = rxdata;
 239         else if (dspi->bytes_per_word == 2)
 240                 *(u16 *)dspi->rx = rxdata;
 241         else /* dspi->bytes_per_word == 4 */
 242                 *(u32 *)dspi->rx = rxdata;
 243         dspi->rx += dspi->bytes_per_word;
 244 }
 245 
 246 static void dspi_tx_dma_callback(void *arg)
 247 {
 248         struct fsl_dspi *dspi = arg;
 249         struct fsl_dspi_dma *dma = dspi->dma;
 250 
 251         complete(&dma->cmd_tx_complete);
 252 }
 253 
 254 static void dspi_rx_dma_callback(void *arg)
 255 {
 256         struct fsl_dspi *dspi = arg;
 257         struct fsl_dspi_dma *dma = dspi->dma;
 258         int i;
 259 
 260         if (dspi->rx) {
 261                 for (i = 0; i < dma->curr_xfer_len; i++)
 262                         dspi_push_rx(dspi, dspi->dma->rx_dma_buf[i]);
 263         }
 264 
 265         complete(&dma->cmd_rx_complete);
 266 }
 267 
 268 static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
 269 {
 270         struct device *dev = &dspi->pdev->dev;
 271         struct fsl_dspi_dma *dma = dspi->dma;
 272         int time_left;
 273         int i;
 274 
 275         for (i = 0; i < dma->curr_xfer_len; i++)
 276                 dspi->dma->tx_dma_buf[i] = dspi_pop_tx_pushr(dspi);
 277 
 278         dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
 279                                         dma->tx_dma_phys,
 280                                         dma->curr_xfer_len *
 281                                         DMA_SLAVE_BUSWIDTH_4_BYTES,
 282                                         DMA_MEM_TO_DEV,
 283                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 284         if (!dma->tx_desc) {
 285                 dev_err(dev, "Not able to get desc for DMA xfer\n");
 286                 return -EIO;
 287         }
 288 
 289         dma->tx_desc->callback = dspi_tx_dma_callback;
 290         dma->tx_desc->callback_param = dspi;
 291         if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
 292                 dev_err(dev, "DMA submit failed\n");
 293                 return -EINVAL;
 294         }
 295 
 296         dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
 297                                         dma->rx_dma_phys,
 298                                         dma->curr_xfer_len *
 299                                         DMA_SLAVE_BUSWIDTH_4_BYTES,
 300                                         DMA_DEV_TO_MEM,
 301                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 302         if (!dma->rx_desc) {
 303                 dev_err(dev, "Not able to get desc for DMA xfer\n");
 304                 return -EIO;
 305         }
 306 
 307         dma->rx_desc->callback = dspi_rx_dma_callback;
 308         dma->rx_desc->callback_param = dspi;
 309         if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
 310                 dev_err(dev, "DMA submit failed\n");
 311                 return -EINVAL;
 312         }
 313 
 314         reinit_completion(&dspi->dma->cmd_rx_complete);
 315         reinit_completion(&dspi->dma->cmd_tx_complete);
 316 
 317         dma_async_issue_pending(dma->chan_rx);
 318         dma_async_issue_pending(dma->chan_tx);
 319 
 320         if (spi_controller_is_slave(dspi->ctlr)) {
 321                 wait_for_completion_interruptible(&dspi->dma->cmd_rx_complete);
 322                 return 0;
 323         }
 324 
 325         time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
 326                                                 DMA_COMPLETION_TIMEOUT);
 327         if (time_left == 0) {
 328                 dev_err(dev, "DMA tx timeout\n");
 329                 dmaengine_terminate_all(dma->chan_tx);
 330                 dmaengine_terminate_all(dma->chan_rx);
 331                 return -ETIMEDOUT;
 332         }
 333 
 334         time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
 335                                                 DMA_COMPLETION_TIMEOUT);
 336         if (time_left == 0) {
 337                 dev_err(dev, "DMA rx timeout\n");
 338                 dmaengine_terminate_all(dma->chan_tx);
 339                 dmaengine_terminate_all(dma->chan_rx);
 340                 return -ETIMEDOUT;
 341         }
 342 
 343         return 0;
 344 }
 345 
 346 static int dspi_dma_xfer(struct fsl_dspi *dspi)
 347 {
 348         struct spi_message *message = dspi->cur_msg;
 349         struct device *dev = &dspi->pdev->dev;
 350         struct fsl_dspi_dma *dma = dspi->dma;
 351         int curr_remaining_bytes;
 352         int bytes_per_buffer;
 353         int ret = 0;
 354 
 355         curr_remaining_bytes = dspi->len;
 356         bytes_per_buffer = DSPI_DMA_BUFSIZE / DSPI_FIFO_SIZE;
 357         while (curr_remaining_bytes) {
 358                 /* Check if current transfer fits the DMA buffer */
 359                 dma->curr_xfer_len = curr_remaining_bytes
 360                         / dspi->bytes_per_word;
 361                 if (dma->curr_xfer_len > bytes_per_buffer)
 362                         dma->curr_xfer_len = bytes_per_buffer;
 363 
 364                 ret = dspi_next_xfer_dma_submit(dspi);
 365                 if (ret) {
 366                         dev_err(dev, "DMA transfer failed\n");
 367                         goto exit;
 368 
 369                 } else {
 370                         const int len =
 371                                 dma->curr_xfer_len * dspi->bytes_per_word;
 372                         curr_remaining_bytes -= len;
 373                         message->actual_length += len;
 374                         if (curr_remaining_bytes < 0)
 375                                 curr_remaining_bytes = 0;
 376                 }
 377         }
 378 
 379 exit:
 380         return ret;
 381 }
 382 
 383 static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
 384 {
 385         struct device *dev = &dspi->pdev->dev;
 386         struct dma_slave_config cfg;
 387         struct fsl_dspi_dma *dma;
 388         int ret;
 389 
 390         dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
 391         if (!dma)
 392                 return -ENOMEM;
 393 
 394         dma->chan_rx = dma_request_slave_channel(dev, "rx");
 395         if (!dma->chan_rx) {
 396                 dev_err(dev, "rx dma channel not available\n");
 397                 ret = -ENODEV;
 398                 return ret;
 399         }
 400 
 401         dma->chan_tx = dma_request_slave_channel(dev, "tx");
 402         if (!dma->chan_tx) {
 403                 dev_err(dev, "tx dma channel not available\n");
 404                 ret = -ENODEV;
 405                 goto err_tx_channel;
 406         }
 407 
 408         dma->tx_dma_buf = dma_alloc_coherent(dev, DSPI_DMA_BUFSIZE,
 409                                              &dma->tx_dma_phys, GFP_KERNEL);
 410         if (!dma->tx_dma_buf) {
 411                 ret = -ENOMEM;
 412                 goto err_tx_dma_buf;
 413         }
 414 
 415         dma->rx_dma_buf = dma_alloc_coherent(dev, DSPI_DMA_BUFSIZE,
 416                                              &dma->rx_dma_phys, GFP_KERNEL);
 417         if (!dma->rx_dma_buf) {
 418                 ret = -ENOMEM;
 419                 goto err_rx_dma_buf;
 420         }
 421 
 422         cfg.src_addr = phy_addr + SPI_POPR;
 423         cfg.dst_addr = phy_addr + SPI_PUSHR;
 424         cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 425         cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 426         cfg.src_maxburst = 1;
 427         cfg.dst_maxburst = 1;
 428 
 429         cfg.direction = DMA_DEV_TO_MEM;
 430         ret = dmaengine_slave_config(dma->chan_rx, &cfg);
 431         if (ret) {
 432                 dev_err(dev, "can't configure rx dma channel\n");
 433                 ret = -EINVAL;
 434                 goto err_slave_config;
 435         }
 436 
 437         cfg.direction = DMA_MEM_TO_DEV;
 438         ret = dmaengine_slave_config(dma->chan_tx, &cfg);
 439         if (ret) {
 440                 dev_err(dev, "can't configure tx dma channel\n");
 441                 ret = -EINVAL;
 442                 goto err_slave_config;
 443         }
 444 
 445         dspi->dma = dma;
 446         init_completion(&dma->cmd_tx_complete);
 447         init_completion(&dma->cmd_rx_complete);
 448 
 449         return 0;
 450 
 451 err_slave_config:
 452         dma_free_coherent(dev, DSPI_DMA_BUFSIZE,
 453                         dma->rx_dma_buf, dma->rx_dma_phys);
 454 err_rx_dma_buf:
 455         dma_free_coherent(dev, DSPI_DMA_BUFSIZE,
 456                         dma->tx_dma_buf, dma->tx_dma_phys);
 457 err_tx_dma_buf:
 458         dma_release_channel(dma->chan_tx);
 459 err_tx_channel:
 460         dma_release_channel(dma->chan_rx);
 461 
 462         devm_kfree(dev, dma);
 463         dspi->dma = NULL;
 464 
 465         return ret;
 466 }
 467 
 468 static void dspi_release_dma(struct fsl_dspi *dspi)
 469 {
 470         struct fsl_dspi_dma *dma = dspi->dma;
 471         struct device *dev = &dspi->pdev->dev;
 472 
 473         if (!dma)
 474                 return;
 475 
 476         if (dma->chan_tx) {
 477                 dma_unmap_single(dev, dma->tx_dma_phys,
 478                                  DSPI_DMA_BUFSIZE, DMA_TO_DEVICE);
 479                 dma_release_channel(dma->chan_tx);
 480         }
 481 
 482         if (dma->chan_rx) {
 483                 dma_unmap_single(dev, dma->rx_dma_phys,
 484                                  DSPI_DMA_BUFSIZE, DMA_FROM_DEVICE);
 485                 dma_release_channel(dma->chan_rx);
 486         }
 487 }
 488 
 489 static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
 490                            unsigned long clkrate)
 491 {
 492         /* Valid baud rate pre-scaler values */
 493         int pbr_tbl[4] = {2, 3, 5, 7};
 494         int brs[16] = { 2,      4,      6,      8,
 495                         16,     32,     64,     128,
 496                         256,    512,    1024,   2048,
 497                         4096,   8192,   16384,  32768 };
 498         int scale_needed, scale, minscale = INT_MAX;
 499         int i, j;
 500 
 501         scale_needed = clkrate / speed_hz;
 502         if (clkrate % speed_hz)
 503                 scale_needed++;
 504 
 505         for (i = 0; i < ARRAY_SIZE(brs); i++)
 506                 for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) {
 507                         scale = brs[i] * pbr_tbl[j];
 508                         if (scale >= scale_needed) {
 509                                 if (scale < minscale) {
 510                                         minscale = scale;
 511                                         *br = i;
 512                                         *pbr = j;
 513                                 }
 514                                 break;
 515                         }
 516                 }
 517 
 518         if (minscale == INT_MAX) {
 519                 pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n",
 520                         speed_hz, clkrate);
 521                 *pbr = ARRAY_SIZE(pbr_tbl) - 1;
 522                 *br =  ARRAY_SIZE(brs) - 1;
 523         }
 524 }
 525 
 526 static void ns_delay_scale(char *psc, char *sc, int delay_ns,
 527                            unsigned long clkrate)
 528 {
 529         int scale_needed, scale, minscale = INT_MAX;
 530         int pscale_tbl[4] = {1, 3, 5, 7};
 531         u32 remainder;
 532         int i, j;
 533 
 534         scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
 535                                    &remainder);
 536         if (remainder)
 537                 scale_needed++;
 538 
 539         for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
 540                 for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
 541                         scale = pscale_tbl[i] * (2 << j);
 542                         if (scale >= scale_needed) {
 543                                 if (scale < minscale) {
 544                                         minscale = scale;
 545                                         *psc = i;
 546                                         *sc = j;
 547                                 }
 548                                 break;
 549                         }
 550                 }
 551 
 552         if (minscale == INT_MAX) {
 553                 pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
 554                         delay_ns, clkrate);
 555                 *psc = ARRAY_SIZE(pscale_tbl) - 1;
 556                 *sc = SPI_CTAR_SCALE_BITS;
 557         }
 558 }
 559 
 560 static void fifo_write(struct fsl_dspi *dspi)
 561 {
 562         regmap_write(dspi->regmap, SPI_PUSHR, dspi_pop_tx_pushr(dspi));
 563 }
 564 
 565 static void cmd_fifo_write(struct fsl_dspi *dspi)
 566 {
 567         u16 cmd = dspi->tx_cmd;
 568 
 569         if (dspi->len > 0)
 570                 cmd |= SPI_PUSHR_CMD_CONT;
 571         regmap_write(dspi->regmap_pushr, PUSHR_CMD, cmd);
 572 }
 573 
 574 static void tx_fifo_write(struct fsl_dspi *dspi, u16 txdata)
 575 {
 576         regmap_write(dspi->regmap_pushr, PUSHR_TX, txdata);
 577 }
 578 
 579 static void dspi_tcfq_write(struct fsl_dspi *dspi)
 580 {
 581         /* Clear transfer count */
 582         dspi->tx_cmd |= SPI_PUSHR_CMD_CTCNT;
 583 
 584         if (dspi->devtype_data->xspi_mode && dspi->bits_per_word > 16) {
 585                 /* Write the CMD FIFO entry first, and then the two
 586                  * corresponding TX FIFO entries.
 587                  */
 588                 u32 data = dspi_pop_tx(dspi);
 589 
 590                 cmd_fifo_write(dspi);
 591                 tx_fifo_write(dspi, data & 0xFFFF);
 592                 tx_fifo_write(dspi, data >> 16);
 593         } else {
 594                 /* Write one entry to both TX FIFO and CMD FIFO
 595                  * simultaneously.
 596                  */
 597                 fifo_write(dspi);
 598         }
 599 }
 600 
 601 static u32 fifo_read(struct fsl_dspi *dspi)
 602 {
 603         u32 rxdata = 0;
 604 
 605         regmap_read(dspi->regmap, SPI_POPR, &rxdata);
 606         return rxdata;
 607 }
 608 
 609 static void dspi_tcfq_read(struct fsl_dspi *dspi)
 610 {
 611         dspi_push_rx(dspi, fifo_read(dspi));
 612 }
 613 
 614 static void dspi_eoq_write(struct fsl_dspi *dspi)
 615 {
 616         int fifo_size = DSPI_FIFO_SIZE;
 617         u16 xfer_cmd = dspi->tx_cmd;
 618 
 619         /* Fill TX FIFO with as many transfers as possible */
 620         while (dspi->len && fifo_size--) {
 621                 dspi->tx_cmd = xfer_cmd;
 622                 /* Request EOQF for last transfer in FIFO */
 623                 if (dspi->len == dspi->bytes_per_word || fifo_size == 0)
 624                         dspi->tx_cmd |= SPI_PUSHR_CMD_EOQ;
 625                 /* Clear transfer count for first transfer in FIFO */
 626                 if (fifo_size == (DSPI_FIFO_SIZE - 1))
 627                         dspi->tx_cmd |= SPI_PUSHR_CMD_CTCNT;
 628                 /* Write combined TX FIFO and CMD FIFO entry */
 629                 fifo_write(dspi);
 630         }
 631 }
 632 
 633 static void dspi_eoq_read(struct fsl_dspi *dspi)
 634 {
 635         int fifo_size = DSPI_FIFO_SIZE;
 636 
 637         /* Read one FIFO entry and push to rx buffer */
 638         while ((dspi->rx < dspi->rx_end) && fifo_size--)
 639                 dspi_push_rx(dspi, fifo_read(dspi));
 640 }
 641 
 642 static int dspi_rxtx(struct fsl_dspi *dspi)
 643 {
 644         struct spi_message *msg = dspi->cur_msg;
 645         enum dspi_trans_mode trans_mode;
 646         u16 spi_tcnt;
 647         u32 spi_tcr;
 648 
 649         /* Get transfer counter (in number of SPI transfers). It was
 650          * reset to 0 when transfer(s) were started.
 651          */
 652         regmap_read(dspi->regmap, SPI_TCR, &spi_tcr);
 653         spi_tcnt = SPI_TCR_GET_TCNT(spi_tcr);
 654         /* Update total number of bytes that were transferred */
 655         msg->actual_length += spi_tcnt * dspi->bytes_per_word;
 656 
 657         trans_mode = dspi->devtype_data->trans_mode;
 658         if (trans_mode == DSPI_EOQ_MODE)
 659                 dspi_eoq_read(dspi);
 660         else if (trans_mode == DSPI_TCFQ_MODE)
 661                 dspi_tcfq_read(dspi);
 662 
 663         if (!dspi->len)
 664                 /* Success! */
 665                 return 0;
 666 
 667         if (trans_mode == DSPI_EOQ_MODE)
 668                 dspi_eoq_write(dspi);
 669         else if (trans_mode == DSPI_TCFQ_MODE)
 670                 dspi_tcfq_write(dspi);
 671 
 672         return -EINPROGRESS;
 673 }
 674 
 675 static int dspi_poll(struct fsl_dspi *dspi)
 676 {
 677         int tries = 1000;
 678         u32 spi_sr;
 679 
 680         do {
 681                 regmap_read(dspi->regmap, SPI_SR, &spi_sr);
 682                 regmap_write(dspi->regmap, SPI_SR, spi_sr);
 683 
 684                 if (spi_sr & (SPI_SR_EOQF | SPI_SR_TCFQF))
 685                         break;
 686         } while (--tries);
 687 
 688         if (!tries)
 689                 return -ETIMEDOUT;
 690 
 691         return dspi_rxtx(dspi);
 692 }
 693 
 694 static irqreturn_t dspi_interrupt(int irq, void *dev_id)
 695 {
 696         struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
 697         u32 spi_sr;
 698 
 699         regmap_read(dspi->regmap, SPI_SR, &spi_sr);
 700         regmap_write(dspi->regmap, SPI_SR, spi_sr);
 701 
 702         if (!(spi_sr & (SPI_SR_EOQF | SPI_SR_TCFQF)))
 703                 return IRQ_NONE;
 704 
 705         if (dspi_rxtx(dspi) == 0)
 706                 complete(&dspi->xfer_done);
 707 
 708         return IRQ_HANDLED;
 709 }
 710 
 711 static int dspi_transfer_one_message(struct spi_controller *ctlr,
 712                                      struct spi_message *message)
 713 {
 714         struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
 715         struct spi_device *spi = message->spi;
 716         enum dspi_trans_mode trans_mode;
 717         struct spi_transfer *transfer;
 718         int status = 0;
 719 
 720         message->actual_length = 0;
 721 
 722         list_for_each_entry(transfer, &message->transfers, transfer_list) {
 723                 dspi->cur_transfer = transfer;
 724                 dspi->cur_msg = message;
 725                 dspi->cur_chip = spi_get_ctldata(spi);
 726                 /* Prepare command word for CMD FIFO */
 727                 dspi->tx_cmd = SPI_PUSHR_CMD_CTAS(0) |
 728                                SPI_PUSHR_CMD_PCS(spi->chip_select);
 729                 if (list_is_last(&dspi->cur_transfer->transfer_list,
 730                                  &dspi->cur_msg->transfers)) {
 731                         /* Leave PCS activated after last transfer when
 732                          * cs_change is set.
 733                          */
 734                         if (transfer->cs_change)
 735                                 dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
 736                 } else {
 737                         /* Keep PCS active between transfers in same message
 738                          * when cs_change is not set, and de-activate PCS
 739                          * between transfers in the same message when
 740                          * cs_change is set.
 741                          */
 742                         if (!transfer->cs_change)
 743                                 dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
 744                 }
 745 
 746                 dspi->void_write_data = dspi->cur_chip->void_write_data;
 747 
 748                 dspi->tx = transfer->tx_buf;
 749                 dspi->rx = transfer->rx_buf;
 750                 dspi->rx_end = dspi->rx + transfer->len;
 751                 dspi->len = transfer->len;
 752                 /* Validated transfer specific frame size (defaults applied) */
 753                 dspi->bits_per_word = transfer->bits_per_word;
 754                 if (transfer->bits_per_word <= 8)
 755                         dspi->bytes_per_word = 1;
 756                 else if (transfer->bits_per_word <= 16)
 757                         dspi->bytes_per_word = 2;
 758                 else
 759                         dspi->bytes_per_word = 4;
 760 
 761                 regmap_update_bits(dspi->regmap, SPI_MCR,
 762                                    SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
 763                                    SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
 764                 regmap_write(dspi->regmap, SPI_CTAR(0),
 765                              dspi->cur_chip->ctar_val |
 766                              SPI_FRAME_BITS(transfer->bits_per_word));
 767                 if (dspi->devtype_data->xspi_mode)
 768                         regmap_write(dspi->regmap, SPI_CTARE(0),
 769                                      SPI_FRAME_EBITS(transfer->bits_per_word) |
 770                                      SPI_CTARE_DTCP(1));
 771 
 772                 trans_mode = dspi->devtype_data->trans_mode;
 773                 switch (trans_mode) {
 774                 case DSPI_EOQ_MODE:
 775                         regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_EOQFE);
 776                         dspi_eoq_write(dspi);
 777                         break;
 778                 case DSPI_TCFQ_MODE:
 779                         regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_TCFQE);
 780                         dspi_tcfq_write(dspi);
 781                         break;
 782                 case DSPI_DMA_MODE:
 783                         regmap_write(dspi->regmap, SPI_RSER,
 784                                      SPI_RSER_TFFFE | SPI_RSER_TFFFD |
 785                                      SPI_RSER_RFDFE | SPI_RSER_RFDFD);
 786                         status = dspi_dma_xfer(dspi);
 787                         break;
 788                 default:
 789                         dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
 790                                 trans_mode);
 791                         status = -EINVAL;
 792                         goto out;
 793                 }
 794 
 795                 if (!dspi->irq) {
 796                         do {
 797                                 status = dspi_poll(dspi);
 798                         } while (status == -EINPROGRESS);
 799                 } else if (trans_mode != DSPI_DMA_MODE) {
 800                         wait_for_completion(&dspi->xfer_done);
 801                         reinit_completion(&dspi->xfer_done);
 802                 }
 803 
 804                 if (transfer->delay_usecs)
 805                         udelay(transfer->delay_usecs);
 806         }
 807 
 808 out:
 809         message->status = status;
 810         spi_finalize_current_message(ctlr);
 811 
 812         return status;
 813 }
 814 
 815 static int dspi_setup(struct spi_device *spi)
 816 {
 817         struct fsl_dspi *dspi = spi_controller_get_devdata(spi->controller);
 818         unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
 819         u32 cs_sck_delay = 0, sck_cs_delay = 0;
 820         struct fsl_dspi_platform_data *pdata;
 821         unsigned char pasc = 0, asc = 0;
 822         struct chip_data *chip;
 823         unsigned long clkrate;
 824 
 825         /* Only alloc on first setup */
 826         chip = spi_get_ctldata(spi);
 827         if (chip == NULL) {
 828                 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
 829                 if (!chip)
 830                         return -ENOMEM;
 831         }
 832 
 833         pdata = dev_get_platdata(&dspi->pdev->dev);
 834 
 835         if (!pdata) {
 836                 of_property_read_u32(spi->dev.of_node, "fsl,spi-cs-sck-delay",
 837                                      &cs_sck_delay);
 838 
 839                 of_property_read_u32(spi->dev.of_node, "fsl,spi-sck-cs-delay",
 840                                      &sck_cs_delay);
 841         } else {
 842                 cs_sck_delay = pdata->cs_sck_delay;
 843                 sck_cs_delay = pdata->sck_cs_delay;
 844         }
 845 
 846         chip->void_write_data = 0;
 847 
 848         clkrate = clk_get_rate(dspi->clk);
 849         hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate);
 850 
 851         /* Set PCS to SCK delay scale values */
 852         ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
 853 
 854         /* Set After SCK delay scale values */
 855         ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
 856 
 857         chip->ctar_val = 0;
 858         if (spi->mode & SPI_CPOL)
 859                 chip->ctar_val |= SPI_CTAR_CPOL;
 860         if (spi->mode & SPI_CPHA)
 861                 chip->ctar_val |= SPI_CTAR_CPHA;
 862 
 863         if (!spi_controller_is_slave(dspi->ctlr)) {
 864                 chip->ctar_val |= SPI_CTAR_PCSSCK(pcssck) |
 865                                   SPI_CTAR_CSSCK(cssck) |
 866                                   SPI_CTAR_PASC(pasc) |
 867                                   SPI_CTAR_ASC(asc) |
 868                                   SPI_CTAR_PBR(pbr) |
 869                                   SPI_CTAR_BR(br);
 870 
 871                 if (spi->mode & SPI_LSB_FIRST)
 872                         chip->ctar_val |= SPI_CTAR_LSBFE;
 873         }
 874 
 875         spi_set_ctldata(spi, chip);
 876 
 877         return 0;
 878 }
 879 
 880 static void dspi_cleanup(struct spi_device *spi)
 881 {
 882         struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
 883 
 884         dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
 885                 spi->controller->bus_num, spi->chip_select);
 886 
 887         kfree(chip);
 888 }
 889 
 890 static const struct of_device_id fsl_dspi_dt_ids[] = {
 891         { .compatible = "fsl,vf610-dspi", .data = &vf610_data, },
 892         { .compatible = "fsl,ls1021a-v1.0-dspi", .data = &ls1021a_v1_data, },
 893         { .compatible = "fsl,ls2085a-dspi", .data = &ls2085a_data, },
 894         { /* sentinel */ }
 895 };
 896 MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
 897 
 898 #ifdef CONFIG_PM_SLEEP
 899 static int dspi_suspend(struct device *dev)
 900 {
 901         struct spi_controller *ctlr = dev_get_drvdata(dev);
 902         struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
 903 
 904         spi_controller_suspend(ctlr);
 905         clk_disable_unprepare(dspi->clk);
 906 
 907         pinctrl_pm_select_sleep_state(dev);
 908 
 909         return 0;
 910 }
 911 
 912 static int dspi_resume(struct device *dev)
 913 {
 914         struct spi_controller *ctlr = dev_get_drvdata(dev);
 915         struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
 916         int ret;
 917 
 918         pinctrl_pm_select_default_state(dev);
 919 
 920         ret = clk_prepare_enable(dspi->clk);
 921         if (ret)
 922                 return ret;
 923         spi_controller_resume(ctlr);
 924 
 925         return 0;
 926 }
 927 #endif /* CONFIG_PM_SLEEP */
 928 
 929 static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume);
 930 
 931 static const struct regmap_range dspi_volatile_ranges[] = {
 932         regmap_reg_range(SPI_MCR, SPI_TCR),
 933         regmap_reg_range(SPI_SR, SPI_SR),
 934         regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
 935 };
 936 
 937 static const struct regmap_access_table dspi_volatile_table = {
 938         .yes_ranges     = dspi_volatile_ranges,
 939         .n_yes_ranges   = ARRAY_SIZE(dspi_volatile_ranges),
 940 };
 941 
 942 static const struct regmap_config dspi_regmap_config = {
 943         .reg_bits       = 32,
 944         .val_bits       = 32,
 945         .reg_stride     = 4,
 946         .max_register   = 0x88,
 947         .volatile_table = &dspi_volatile_table,
 948 };
 949 
 950 static const struct regmap_range dspi_xspi_volatile_ranges[] = {
 951         regmap_reg_range(SPI_MCR, SPI_TCR),
 952         regmap_reg_range(SPI_SR, SPI_SR),
 953         regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
 954         regmap_reg_range(SPI_SREX, SPI_SREX),
 955 };
 956 
 957 static const struct regmap_access_table dspi_xspi_volatile_table = {
 958         .yes_ranges     = dspi_xspi_volatile_ranges,
 959         .n_yes_ranges   = ARRAY_SIZE(dspi_xspi_volatile_ranges),
 960 };
 961 
 962 static const struct regmap_config dspi_xspi_regmap_config[] = {
 963         {
 964                 .reg_bits       = 32,
 965                 .val_bits       = 32,
 966                 .reg_stride     = 4,
 967                 .max_register   = 0x13c,
 968                 .volatile_table = &dspi_xspi_volatile_table,
 969         },
 970         {
 971                 .name           = "pushr",
 972                 .reg_bits       = 16,
 973                 .val_bits       = 16,
 974                 .reg_stride     = 2,
 975                 .max_register   = 0x2,
 976         },
 977 };
 978 
 979 static void dspi_init(struct fsl_dspi *dspi)
 980 {
 981         unsigned int mcr = SPI_MCR_PCSIS;
 982 
 983         if (dspi->devtype_data->xspi_mode)
 984                 mcr |= SPI_MCR_XSPI;
 985         if (!spi_controller_is_slave(dspi->ctlr))
 986                 mcr |= SPI_MCR_MASTER;
 987 
 988         regmap_write(dspi->regmap, SPI_MCR, mcr);
 989         regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
 990         if (dspi->devtype_data->xspi_mode)
 991                 regmap_write(dspi->regmap, SPI_CTARE(0),
 992                              SPI_CTARE_FMSZE(0) | SPI_CTARE_DTCP(1));
 993 }
 994 
 995 static int dspi_probe(struct platform_device *pdev)
 996 {
 997         struct device_node *np = pdev->dev.of_node;
 998         const struct regmap_config *regmap_config;
 999         struct fsl_dspi_platform_data *pdata;
1000         struct spi_controller *ctlr;
1001         int ret, cs_num, bus_num;
1002         struct fsl_dspi *dspi;
1003         struct resource *res;
1004         void __iomem *base;
1005 
1006         ctlr = spi_alloc_master(&pdev->dev, sizeof(struct fsl_dspi));
1007         if (!ctlr)
1008                 return -ENOMEM;
1009 
1010         dspi = spi_controller_get_devdata(ctlr);
1011         dspi->pdev = pdev;
1012         dspi->ctlr = ctlr;
1013 
1014         ctlr->setup = dspi_setup;
1015         ctlr->transfer_one_message = dspi_transfer_one_message;
1016         ctlr->dev.of_node = pdev->dev.of_node;
1017 
1018         ctlr->cleanup = dspi_cleanup;
1019         ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1020 
1021         pdata = dev_get_platdata(&pdev->dev);
1022         if (pdata) {
1023                 ctlr->num_chipselect = pdata->cs_num;
1024                 ctlr->bus_num = pdata->bus_num;
1025 
1026                 dspi->devtype_data = &coldfire_data;
1027         } else {
1028 
1029                 ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
1030                 if (ret < 0) {
1031                         dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
1032                         goto out_ctlr_put;
1033                 }
1034                 ctlr->num_chipselect = cs_num;
1035 
1036                 ret = of_property_read_u32(np, "bus-num", &bus_num);
1037                 if (ret < 0) {
1038                         dev_err(&pdev->dev, "can't get bus-num\n");
1039                         goto out_ctlr_put;
1040                 }
1041                 ctlr->bus_num = bus_num;
1042 
1043                 if (of_property_read_bool(np, "spi-slave"))
1044                         ctlr->slave = true;
1045 
1046                 dspi->devtype_data = of_device_get_match_data(&pdev->dev);
1047                 if (!dspi->devtype_data) {
1048                         dev_err(&pdev->dev, "can't get devtype_data\n");
1049                         ret = -EFAULT;
1050                         goto out_ctlr_put;
1051                 }
1052         }
1053 
1054         if (dspi->devtype_data->xspi_mode)
1055                 ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1056         else
1057                 ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1058 
1059         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1060         base = devm_ioremap_resource(&pdev->dev, res);
1061         if (IS_ERR(base)) {
1062                 ret = PTR_ERR(base);
1063                 goto out_ctlr_put;
1064         }
1065 
1066         if (dspi->devtype_data->xspi_mode)
1067                 regmap_config = &dspi_xspi_regmap_config[0];
1068         else
1069                 regmap_config = &dspi_regmap_config;
1070         dspi->regmap = devm_regmap_init_mmio(&pdev->dev, base, regmap_config);
1071         if (IS_ERR(dspi->regmap)) {
1072                 dev_err(&pdev->dev, "failed to init regmap: %ld\n",
1073                                 PTR_ERR(dspi->regmap));
1074                 ret = PTR_ERR(dspi->regmap);
1075                 goto out_ctlr_put;
1076         }
1077 
1078         if (dspi->devtype_data->xspi_mode) {
1079                 dspi->regmap_pushr = devm_regmap_init_mmio(
1080                         &pdev->dev, base + SPI_PUSHR,
1081                         &dspi_xspi_regmap_config[1]);
1082                 if (IS_ERR(dspi->regmap_pushr)) {
1083                         dev_err(&pdev->dev,
1084                                 "failed to init pushr regmap: %ld\n",
1085                                 PTR_ERR(dspi->regmap_pushr));
1086                         ret = PTR_ERR(dspi->regmap_pushr);
1087                         goto out_ctlr_put;
1088                 }
1089         }
1090 
1091         dspi->clk = devm_clk_get(&pdev->dev, "dspi");
1092         if (IS_ERR(dspi->clk)) {
1093                 ret = PTR_ERR(dspi->clk);
1094                 dev_err(&pdev->dev, "unable to get clock\n");
1095                 goto out_ctlr_put;
1096         }
1097         ret = clk_prepare_enable(dspi->clk);
1098         if (ret)
1099                 goto out_ctlr_put;
1100 
1101         dspi_init(dspi);
1102 
1103         dspi->irq = platform_get_irq(pdev, 0);
1104         if (dspi->irq <= 0) {
1105                 dev_info(&pdev->dev,
1106                          "can't get platform irq, using poll mode\n");
1107                 dspi->irq = 0;
1108                 goto poll_mode;
1109         }
1110 
1111         ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt,
1112                                IRQF_SHARED, pdev->name, dspi);
1113         if (ret < 0) {
1114                 dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
1115                 goto out_clk_put;
1116         }
1117 
1118         init_completion(&dspi->xfer_done);
1119 
1120 poll_mode:
1121         if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1122                 ret = dspi_request_dma(dspi, res->start);
1123                 if (ret < 0) {
1124                         dev_err(&pdev->dev, "can't get dma channels\n");
1125                         goto out_clk_put;
1126                 }
1127         }
1128 
1129         ctlr->max_speed_hz =
1130                 clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
1131 
1132         platform_set_drvdata(pdev, ctlr);
1133 
1134         ret = spi_register_controller(ctlr);
1135         if (ret != 0) {
1136                 dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");
1137                 goto out_clk_put;
1138         }
1139 
1140         return ret;
1141 
1142 out_clk_put:
1143         clk_disable_unprepare(dspi->clk);
1144 out_ctlr_put:
1145         spi_controller_put(ctlr);
1146 
1147         return ret;
1148 }
1149 
1150 static int dspi_remove(struct platform_device *pdev)
1151 {
1152         struct spi_controller *ctlr = platform_get_drvdata(pdev);
1153         struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
1154 
1155         /* Disconnect from the SPI framework */
1156         dspi_release_dma(dspi);
1157         clk_disable_unprepare(dspi->clk);
1158         spi_unregister_controller(dspi->ctlr);
1159 
1160         return 0;
1161 }
1162 
1163 static struct platform_driver fsl_dspi_driver = {
1164         .driver.name            = DRIVER_NAME,
1165         .driver.of_match_table  = fsl_dspi_dt_ids,
1166         .driver.owner           = THIS_MODULE,
1167         .driver.pm              = &dspi_pm,
1168         .probe                  = dspi_probe,
1169         .remove                 = dspi_remove,
1170 };
1171 module_platform_driver(fsl_dspi_driver);
1172 
1173 MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
1174 MODULE_LICENSE("GPL");
1175 MODULE_ALIAS("platform:" DRIVER_NAME);

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