drivers/spi/spi-fsl-lpspi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // Freescale i.MX7ULP LPSPI driver
   4 //
   5 // Copyright 2016 Freescale Semiconductor, Inc.
   6 // Copyright 2018 NXP Semiconductors
   7
   8 #include <linux/clk.h>
   9 #include <linux/completion.h>
  10 #include <linux/delay.h>
  11 #include <linux/dmaengine.h>
  12 #include <linux/dma-mapping.h>
  13 #include <linux/err.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/io.h>
  16 #include <linux/irq.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/of.h>
  20 #include <linux/pinctrl/consumer.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/dma/imx-dma.h>
  23 #include <linux/pm_runtime.h>
  24 #include <linux/slab.h>
  25 #include <linux/spi/spi.h>
  26 #include <linux/spi/spi_bitbang.h>
  27 #include <linux/types.h>
  28
  29 #define DRIVER_NAME "fsl_lpspi"
  30
  31 #define FSL_LPSPI_RPM_TIMEOUT 50 /* 50ms */
  32
  33 /* The maximum bytes that edma can transfer once.*/
  34 #define FSL_LPSPI_MAX_EDMA_BYTES  ((1 << 15) - 1)
  35
  36 /* i.MX7ULP LPSPI registers */
  37 #define IMX7ULP_VERID   0x0
  38 #define IMX7ULP_PARAM   0x4
  39 #define IMX7ULP_CR      0x10
  40 #define IMX7ULP_SR      0x14
  41 #define IMX7ULP_IER     0x18
  42 #define IMX7ULP_DER     0x1c
  43 #define IMX7ULP_CFGR0   0x20
  44 #define IMX7ULP_CFGR1   0x24
  45 #define IMX7ULP_DMR0    0x30
  46 #define IMX7ULP_DMR1    0x34
  47 #define IMX7ULP_CCR     0x40
  48 #define IMX7ULP_FCR     0x58
  49 #define IMX7ULP_FSR     0x5c
  50 #define IMX7ULP_TCR     0x60
  51 #define IMX7ULP_TDR     0x64
  52 #define IMX7ULP_RSR     0x70
  53 #define IMX7ULP_RDR     0x74
  54
  55 /* General control register field define */
  56 #define CR_RRF          BIT(9)
  57 #define CR_RTF          BIT(8)
  58 #define CR_RST          BIT(1)
  59 #define CR_MEN          BIT(0)
  60 #define SR_MBF          BIT(24)
  61 #define SR_TCF          BIT(10)
  62 #define SR_FCF          BIT(9)
  63 #define SR_RDF          BIT(1)
  64 #define SR_TDF          BIT(0)
  65 #define IER_TCIE        BIT(10)
  66 #define IER_FCIE        BIT(9)
  67 #define IER_RDIE        BIT(1)
  68 #define IER_TDIE        BIT(0)
  69 #define DER_RDDE        BIT(1)
  70 #define DER_TDDE        BIT(0)
  71 #define CFGR1_PCSCFG    BIT(27)
  72 #define CFGR1_PINCFG    (BIT(24)|BIT(25))
  73 #define CFGR1_PCSPOL    BIT(8)
  74 #define CFGR1_NOSTALL   BIT(3)
  75 #define CFGR1_HOST      BIT(0)
  76 #define FSR_TXCOUNT     (0xFF)
  77 #define RSR_RXEMPTY     BIT(1)
  78 #define TCR_CPOL        BIT(31)
  79 #define TCR_CPHA        BIT(30)
  80 #define TCR_CONT        BIT(21)
  81 #define TCR_CONTC       BIT(20)
  82 #define TCR_RXMSK       BIT(19)
  83 #define TCR_TXMSK       BIT(18)
  84
  85 struct fsl_lpspi_devtype_data {
  86         u8 prescale_max;
  87 };
  88
  89 struct lpspi_config {
  90         u8 bpw;
  91         u8 chip_select;
  92         u8 prescale;
  93         u16 mode;
  94         u32 speed_hz;
  95         u32 effective_speed_hz;
  96 };
  97
  98 struct fsl_lpspi_data {
  99         struct device *dev;
 100         void __iomem *base;
 101         unsigned long base_phys;
 102         struct clk *clk_ipg;
 103         struct clk *clk_per;
 104         bool is_target;
 105         bool is_only_cs1;
 106         bool is_first_byte;
 107
 108         void *rx_buf;
 109         const void *tx_buf;
 110         void (*tx)(struct fsl_lpspi_data *);
 111         void (*rx)(struct fsl_lpspi_data *);
 112
 113         u32 remain;
 114         u8 watermark;
 115         u8 txfifosize;
 116         u8 rxfifosize;
 117
 118         struct lpspi_config config;
 119         struct completion xfer_done;
 120
 121         bool target_aborted;
 122
 123         /* DMA */
 124         bool usedma;
 125         struct completion dma_rx_completion;
 126         struct completion dma_tx_completion;
 127
 128         const struct fsl_lpspi_devtype_data *devtype_data;
 129 };
 130
 131 /*
 132  * ERR051608 fixed or not:
 133  * https://www.nxp.com/docs/en/errata/i.MX93_1P87f.pdf
 134  */
 135 static struct fsl_lpspi_devtype_data imx93_lpspi_devtype_data = {
 136         .prescale_max = 1,
 137 };
 138
 139 static struct fsl_lpspi_devtype_data imx7ulp_lpspi_devtype_data = {
 140         .prescale_max = 7,
 141 };
 142
 143 static const struct of_device_id fsl_lpspi_dt_ids[] = {
 144         { .compatible = "fsl,imx7ulp-spi", .data = &imx7ulp_lpspi_devtype_data,},
 145         { .compatible = "fsl,imx93-spi", .data = &imx93_lpspi_devtype_data,},
 146         { /* sentinel */ }
 147 };
 148 MODULE_DEVICE_TABLE(of, fsl_lpspi_dt_ids);
 149
 150 #define LPSPI_BUF_RX(type)                                              \
 151 static void fsl_lpspi_buf_rx_##type(struct fsl_lpspi_data *fsl_lpspi)   \
 152 {                                                                       \
 153         unsigned int val = readl(fsl_lpspi->base + IMX7ULP_RDR);        \
 154                                                                         \
 155         if (fsl_lpspi->rx_buf) {                                        \
 156                 *(type *)fsl_lpspi->rx_buf = val;                       \
 157                 fsl_lpspi->rx_buf += sizeof(type);                      \
 158         }                                                               \
 159 }
 160
 161 #define LPSPI_BUF_TX(type)                                              \
 162 static void fsl_lpspi_buf_tx_##type(struct fsl_lpspi_data *fsl_lpspi)   \
 163 {                                                                       \
 164         type val = 0;                                                   \
 165                                                                         \
 166         if (fsl_lpspi->tx_buf) {                                        \
 167                 val = *(type *)fsl_lpspi->tx_buf;                       \
 168                 fsl_lpspi->tx_buf += sizeof(type);                      \
 169         }                                                               \
 170                                                                         \
 171         fsl_lpspi->remain -= sizeof(type);                              \
 172         writel(val, fsl_lpspi->base + IMX7ULP_TDR);                     \
 173 }
 174
 175 LPSPI_BUF_RX(u8)
 176 LPSPI_BUF_TX(u8)
 177 LPSPI_BUF_RX(u16)
 178 LPSPI_BUF_TX(u16)
 179 LPSPI_BUF_RX(u32)
 180 LPSPI_BUF_TX(u32)
 181
 182 static void fsl_lpspi_intctrl(struct fsl_lpspi_data *fsl_lpspi,
 183                               unsigned int enable)
 184 {
 185         writel(enable, fsl_lpspi->base + IMX7ULP_IER);
 186 }
 187
 188 static int fsl_lpspi_bytes_per_word(const int bpw)
 189 {
 190         return DIV_ROUND_UP(bpw, BITS_PER_BYTE);
 191 }
 192
 193 static bool fsl_lpspi_can_dma(struct spi_controller *controller,
 194                               struct spi_device *spi,
 195                               struct spi_transfer *transfer)
 196 {
 197         unsigned int bytes_per_word;
 198
 199         if (!controller->dma_rx)
 200                 return false;
 201
 202         bytes_per_word = fsl_lpspi_bytes_per_word(transfer->bits_per_word);
 203
 204         switch (bytes_per_word) {
 205         case 1:
 206         case 2:
 207         case 4:
 208                 break;
 209         default:
 210                 return false;
 211         }
 212
 213         return true;
 214 }
 215
 216 static int lpspi_prepare_xfer_hardware(struct spi_controller *controller)
 217 {
 218         struct fsl_lpspi_data *fsl_lpspi =
 219                                 spi_controller_get_devdata(controller);
 220         int ret;
 221
 222         ret = pm_runtime_resume_and_get(fsl_lpspi->dev);
 223         if (ret < 0) {
 224                 dev_err(fsl_lpspi->dev, "failed to enable clock\n");
 225                 return ret;
 226         }
 227
 228         return 0;
 229 }
 230
 231 static int lpspi_unprepare_xfer_hardware(struct spi_controller *controller)
 232 {
 233         struct fsl_lpspi_data *fsl_lpspi =
 234                                 spi_controller_get_devdata(controller);
 235
 236         pm_runtime_mark_last_busy(fsl_lpspi->dev);
 237         pm_runtime_put_autosuspend(fsl_lpspi->dev);
 238
 239         return 0;
 240 }
 241
 242 static void fsl_lpspi_write_tx_fifo(struct fsl_lpspi_data *fsl_lpspi)
 243 {
 244         u8 txfifo_cnt;
 245         u32 temp;
 246
 247         txfifo_cnt = readl(fsl_lpspi->base + IMX7ULP_FSR) & 0xff;
 248
 249         while (txfifo_cnt < fsl_lpspi->txfifosize) {
 250                 if (!fsl_lpspi->remain)
 251                         break;
 252                 fsl_lpspi->tx(fsl_lpspi);
 253                 txfifo_cnt++;
 254         }
 255
 256         if (txfifo_cnt < fsl_lpspi->txfifosize) {
 257                 if (!fsl_lpspi->is_target) {
 258                         temp = readl(fsl_lpspi->base + IMX7ULP_TCR);
 259                         temp &= ~TCR_CONTC;
 260                         writel(temp, fsl_lpspi->base + IMX7ULP_TCR);
 261                 }
 262
 263                 fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE);
 264         } else
 265                 fsl_lpspi_intctrl(fsl_lpspi, IER_TDIE);
 266 }
 267
 268 static void fsl_lpspi_read_rx_fifo(struct fsl_lpspi_data *fsl_lpspi)
 269 {
 270         while (!(readl(fsl_lpspi->base + IMX7ULP_RSR) & RSR_RXEMPTY))
 271                 fsl_lpspi->rx(fsl_lpspi);
 272 }
 273
 274 static void fsl_lpspi_set_cmd(struct fsl_lpspi_data *fsl_lpspi)
 275 {
 276         u32 temp = 0;
 277
 278         temp |= fsl_lpspi->config.bpw - 1;
 279         temp |= (fsl_lpspi->config.mode & 0x3) << 30;
 280         temp |= (fsl_lpspi->config.chip_select & 0x3) << 24;
 281         if (!fsl_lpspi->is_target) {
 282                 temp |= fsl_lpspi->config.prescale << 27;
 283                 /*
 284                  * Set TCR_CONT will keep SS asserted after current transfer.
 285                  * For the first transfer, clear TCR_CONTC to assert SS.
 286                  * For subsequent transfer, set TCR_CONTC to keep SS asserted.
 287                  */
 288                 if (!fsl_lpspi->usedma) {
 289                         temp |= TCR_CONT;
 290                         if (fsl_lpspi->is_first_byte)
 291                                 temp &= ~TCR_CONTC;
 292                         else
 293                                 temp |= TCR_CONTC;
 294                 }
 295         }
 296         writel(temp, fsl_lpspi->base + IMX7ULP_TCR);
 297
 298         dev_dbg(fsl_lpspi->dev, "TCR=0x%x\n", temp);
 299 }
 300
 301 static void fsl_lpspi_set_watermark(struct fsl_lpspi_data *fsl_lpspi)
 302 {
 303         u32 temp;
 304
 305         if (!fsl_lpspi->usedma)
 306                 temp = fsl_lpspi->watermark >> 1 |
 307                        (fsl_lpspi->watermark >> 1) << 16;
 308         else
 309                 temp = fsl_lpspi->watermark >> 1;
 310
 311         writel(temp, fsl_lpspi->base + IMX7ULP_FCR);
 312
 313         dev_dbg(fsl_lpspi->dev, "FCR=0x%x\n", temp);
 314 }
 315
 316 static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi)
 317 {
 318         struct lpspi_config config = fsl_lpspi->config;
 319         unsigned int perclk_rate, div;
 320         u8 prescale_max;
 321         u8 prescale;
 322         int scldiv;
 323
 324         perclk_rate = clk_get_rate(fsl_lpspi->clk_per);
 325         prescale_max = fsl_lpspi->devtype_data->prescale_max;
 326
 327         if (!config.speed_hz) {
 328                 dev_err(fsl_lpspi->dev,
 329                         "error: the transmission speed provided is 0!\n");
 330                 return -EINVAL;
 331         }
 332
 333         if (config.speed_hz > perclk_rate / 2) {
 334                 dev_err(fsl_lpspi->dev,
 335                       "per-clk should be at least two times of transfer speed");
 336                 return -EINVAL;
 337         }
 338
 339         div = DIV_ROUND_UP(perclk_rate, config.speed_hz);
 340
 341         for (prescale = 0; prescale <= prescale_max; prescale++) {
 342                 scldiv = div / (1 << prescale) - 2;
 343                 if (scldiv >= 0 && scldiv < 256) {
 344                         fsl_lpspi->config.prescale = prescale;
 345                         break;
 346                 }
 347         }
 348
 349         if (scldiv < 0 || scldiv >= 256)
 350                 return -EINVAL;
 351
 352         writel(scldiv | (scldiv << 8) | ((scldiv >> 1) << 16),
 353                                         fsl_lpspi->base + IMX7ULP_CCR);
 354
 355         fsl_lpspi->config.effective_speed_hz = perclk_rate / (scldiv + 2) *
 356                                                (1 << prescale);
 357
 358         dev_dbg(fsl_lpspi->dev, "perclk=%u, speed=%u, prescale=%u, scldiv=%d\n",
 359                 perclk_rate, config.speed_hz, prescale, scldiv);
 360
 361         return 0;
 362 }
 363
 364 static int fsl_lpspi_dma_configure(struct spi_controller *controller)
 365 {
 366         int ret;
 367         enum dma_slave_buswidth buswidth;
 368         struct dma_slave_config rx = {}, tx = {};
 369         struct fsl_lpspi_data *fsl_lpspi =
 370                                 spi_controller_get_devdata(controller);
 371
 372         switch (fsl_lpspi_bytes_per_word(fsl_lpspi->config.bpw)) {
 373         case 4:
 374                 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
 375                 break;
 376         case 2:
 377                 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
 378                 break;
 379         case 1:
 380                 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
 381                 break;
 382         default:
 383                 return -EINVAL;
 384         }
 385
 386         tx.direction = DMA_MEM_TO_DEV;
 387         tx.dst_addr = fsl_lpspi->base_phys + IMX7ULP_TDR;
 388         tx.dst_addr_width = buswidth;
 389         tx.dst_maxburst = 1;
 390         ret = dmaengine_slave_config(controller->dma_tx, &tx);
 391         if (ret) {
 392                 dev_err(fsl_lpspi->dev, "TX dma configuration failed with %d\n",
 393                         ret);
 394                 return ret;
 395         }
 396
 397         rx.direction = DMA_DEV_TO_MEM;
 398         rx.src_addr = fsl_lpspi->base_phys + IMX7ULP_RDR;
 399         rx.src_addr_width = buswidth;
 400         rx.src_maxburst = 1;
 401         ret = dmaengine_slave_config(controller->dma_rx, &rx);
 402         if (ret) {
 403                 dev_err(fsl_lpspi->dev, "RX dma configuration failed with %d\n",
 404                         ret);
 405                 return ret;
 406         }
 407
 408         return 0;
 409 }
 410
 411 static int fsl_lpspi_config(struct fsl_lpspi_data *fsl_lpspi)
 412 {
 413         u32 temp;
 414         int ret;
 415
 416         if (!fsl_lpspi->is_target) {
 417                 ret = fsl_lpspi_set_bitrate(fsl_lpspi);
 418                 if (ret)
 419                         return ret;
 420         }
 421
 422         fsl_lpspi_set_watermark(fsl_lpspi);
 423
 424         if (!fsl_lpspi->is_target)
 425                 temp = CFGR1_HOST;
 426         else
 427                 temp = CFGR1_PINCFG;
 428         if (fsl_lpspi->config.mode & SPI_CS_HIGH)
 429                 temp |= CFGR1_PCSPOL;
 430         writel(temp, fsl_lpspi->base + IMX7ULP_CFGR1);
 431
 432         temp = readl(fsl_lpspi->base + IMX7ULP_CR);
 433         temp |= CR_RRF | CR_RTF | CR_MEN;
 434         writel(temp, fsl_lpspi->base + IMX7ULP_CR);
 435
 436         temp = 0;
 437         if (fsl_lpspi->usedma)
 438                 temp = DER_TDDE | DER_RDDE;
 439         writel(temp, fsl_lpspi->base + IMX7ULP_DER);
 440
 441         return 0;
 442 }
 443
 444 static int fsl_lpspi_setup_transfer(struct spi_controller *controller,
 445                                      struct spi_device *spi,
 446                                      struct spi_transfer *t)
 447 {
 448         struct fsl_lpspi_data *fsl_lpspi =
 449                                 spi_controller_get_devdata(spi->controller);
 450
 451         if (t == NULL)
 452                 return -EINVAL;
 453
 454         fsl_lpspi->config.mode = spi->mode;
 455         fsl_lpspi->config.bpw = t->bits_per_word;
 456         fsl_lpspi->config.speed_hz = t->speed_hz;
 457         if (fsl_lpspi->is_only_cs1)
 458                 fsl_lpspi->config.chip_select = 1;
 459         else
 460                 fsl_lpspi->config.chip_select = spi_get_chipselect(spi, 0);
 461
 462         if (!fsl_lpspi->config.speed_hz)
 463                 fsl_lpspi->config.speed_hz = spi->max_speed_hz;
 464         if (!fsl_lpspi->config.bpw)
 465                 fsl_lpspi->config.bpw = spi->bits_per_word;
 466
 467         /* Initialize the functions for transfer */
 468         if (fsl_lpspi->config.bpw <= 8) {
 469                 fsl_lpspi->rx = fsl_lpspi_buf_rx_u8;
 470                 fsl_lpspi->tx = fsl_lpspi_buf_tx_u8;
 471         } else if (fsl_lpspi->config.bpw <= 16) {
 472                 fsl_lpspi->rx = fsl_lpspi_buf_rx_u16;
 473                 fsl_lpspi->tx = fsl_lpspi_buf_tx_u16;
 474         } else {
 475                 fsl_lpspi->rx = fsl_lpspi_buf_rx_u32;
 476                 fsl_lpspi->tx = fsl_lpspi_buf_tx_u32;
 477         }
 478
 479         if (t->len <= fsl_lpspi->txfifosize)
 480                 fsl_lpspi->watermark = t->len;
 481         else
 482                 fsl_lpspi->watermark = fsl_lpspi->txfifosize;
 483
 484         if (fsl_lpspi_can_dma(controller, spi, t))
 485                 fsl_lpspi->usedma = true;
 486         else
 487                 fsl_lpspi->usedma = false;
 488
 489         return fsl_lpspi_config(fsl_lpspi);
 490 }
 491
 492 static int fsl_lpspi_target_abort(struct spi_controller *controller)
 493 {
 494         struct fsl_lpspi_data *fsl_lpspi =
 495                                 spi_controller_get_devdata(controller);
 496
 497         fsl_lpspi->target_aborted = true;
 498         if (!fsl_lpspi->usedma)
 499                 complete(&fsl_lpspi->xfer_done);
 500         else {
 501                 complete(&fsl_lpspi->dma_tx_completion);
 502                 complete(&fsl_lpspi->dma_rx_completion);
 503         }
 504
 505         return 0;
 506 }
 507
 508 static int fsl_lpspi_wait_for_completion(struct spi_controller *controller)
 509 {
 510         struct fsl_lpspi_data *fsl_lpspi =
 511                                 spi_controller_get_devdata(controller);
 512
 513         if (fsl_lpspi->is_target) {
 514                 if (wait_for_completion_interruptible(&fsl_lpspi->xfer_done) ||
 515                         fsl_lpspi->target_aborted) {
 516                         dev_dbg(fsl_lpspi->dev, "interrupted\n");
 517                         return -EINTR;
 518                 }
 519         } else {
 520                 if (!wait_for_completion_timeout(&fsl_lpspi->xfer_done, HZ)) {
 521                         dev_dbg(fsl_lpspi->dev, "wait for completion timeout\n");
 522                         return -ETIMEDOUT;
 523                 }
 524         }
 525
 526         return 0;
 527 }
 528
 529 static int fsl_lpspi_reset(struct fsl_lpspi_data *fsl_lpspi)
 530 {
 531         u32 temp;
 532
 533         if (!fsl_lpspi->usedma) {
 534                 /* Disable all interrupt */
 535                 fsl_lpspi_intctrl(fsl_lpspi, 0);
 536         }
 537
 538         /* W1C for all flags in SR */
 539         temp = 0x3F << 8;
 540         writel(temp, fsl_lpspi->base + IMX7ULP_SR);
 541
 542         /* Clear FIFO and disable module */
 543         temp = CR_RRF | CR_RTF;
 544         writel(temp, fsl_lpspi->base + IMX7ULP_CR);
 545
 546         return 0;
 547 }
 548
 549 static void fsl_lpspi_dma_rx_callback(void *cookie)
 550 {
 551         struct fsl_lpspi_data *fsl_lpspi = (struct fsl_lpspi_data *)cookie;
 552
 553         complete(&fsl_lpspi->dma_rx_completion);
 554 }
 555
 556 static void fsl_lpspi_dma_tx_callback(void *cookie)
 557 {
 558         struct fsl_lpspi_data *fsl_lpspi = (struct fsl_lpspi_data *)cookie;
 559
 560         complete(&fsl_lpspi->dma_tx_completion);
 561 }
 562
 563 static int fsl_lpspi_calculate_timeout(struct fsl_lpspi_data *fsl_lpspi,
 564                                        int size)
 565 {
 566         unsigned long timeout = 0;
 567
 568         /* Time with actual data transfer and CS change delay related to HW */
 569         timeout = (8 + 4) * size / fsl_lpspi->config.speed_hz;
 570
 571         /* Add extra second for scheduler related activities */
 572         timeout += 1;
 573
 574         /* Double calculated timeout */
 575         return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
 576 }
 577
 578 static int fsl_lpspi_dma_transfer(struct spi_controller *controller,
 579                                 struct fsl_lpspi_data *fsl_lpspi,
 580                                 struct spi_transfer *transfer)
 581 {
 582         struct dma_async_tx_descriptor *desc_tx, *desc_rx;
 583         unsigned long transfer_timeout;
 584         unsigned long time_left;
 585         struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
 586         int ret;
 587
 588         ret = fsl_lpspi_dma_configure(controller);
 589         if (ret)
 590                 return ret;
 591
 592         desc_rx = dmaengine_prep_slave_sg(controller->dma_rx,
 593                                 rx->sgl, rx->nents, DMA_DEV_TO_MEM,
 594                                 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 595         if (!desc_rx)
 596                 return -EINVAL;
 597
 598         desc_rx->callback = fsl_lpspi_dma_rx_callback;
 599         desc_rx->callback_param = (void *)fsl_lpspi;
 600         dmaengine_submit(desc_rx);
 601         reinit_completion(&fsl_lpspi->dma_rx_completion);
 602         dma_async_issue_pending(controller->dma_rx);
 603
 604         desc_tx = dmaengine_prep_slave_sg(controller->dma_tx,
 605                                 tx->sgl, tx->nents, DMA_MEM_TO_DEV,
 606                                 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 607         if (!desc_tx) {
 608                 dmaengine_terminate_all(controller->dma_tx);
 609                 return -EINVAL;
 610         }
 611
 612         desc_tx->callback = fsl_lpspi_dma_tx_callback;
 613         desc_tx->callback_param = (void *)fsl_lpspi;
 614         dmaengine_submit(desc_tx);
 615         reinit_completion(&fsl_lpspi->dma_tx_completion);
 616         dma_async_issue_pending(controller->dma_tx);
 617
 618         fsl_lpspi->target_aborted = false;
 619
 620         if (!fsl_lpspi->is_target) {
 621                 transfer_timeout = fsl_lpspi_calculate_timeout(fsl_lpspi,
 622                                                                transfer->len);
 623
 624                 /* Wait eDMA to finish the data transfer.*/
 625                 time_left = wait_for_completion_timeout(&fsl_lpspi->dma_tx_completion,
 626                                                         transfer_timeout);
 627                 if (!time_left) {
 628                         dev_err(fsl_lpspi->dev, "I/O Error in DMA TX\n");
 629                         dmaengine_terminate_all(controller->dma_tx);
 630                         dmaengine_terminate_all(controller->dma_rx);
 631                         fsl_lpspi_reset(fsl_lpspi);
 632                         return -ETIMEDOUT;
 633                 }
 634
 635                 time_left = wait_for_completion_timeout(&fsl_lpspi->dma_rx_completion,
 636                                                         transfer_timeout);
 637                 if (!time_left) {
 638                         dev_err(fsl_lpspi->dev, "I/O Error in DMA RX\n");
 639                         dmaengine_terminate_all(controller->dma_tx);
 640                         dmaengine_terminate_all(controller->dma_rx);
 641                         fsl_lpspi_reset(fsl_lpspi);
 642                         return -ETIMEDOUT;
 643                 }
 644         } else {
 645                 if (wait_for_completion_interruptible(&fsl_lpspi->dma_tx_completion) ||
 646                         fsl_lpspi->target_aborted) {
 647                         dev_dbg(fsl_lpspi->dev,
 648                                 "I/O Error in DMA TX interrupted\n");
 649                         dmaengine_terminate_all(controller->dma_tx);
 650                         dmaengine_terminate_all(controller->dma_rx);
 651                         fsl_lpspi_reset(fsl_lpspi);
 652                         return -EINTR;
 653                 }
 654
 655                 if (wait_for_completion_interruptible(&fsl_lpspi->dma_rx_completion) ||
 656                         fsl_lpspi->target_aborted) {
 657                         dev_dbg(fsl_lpspi->dev,
 658                                 "I/O Error in DMA RX interrupted\n");
 659                         dmaengine_terminate_all(controller->dma_tx);
 660                         dmaengine_terminate_all(controller->dma_rx);
 661                         fsl_lpspi_reset(fsl_lpspi);
 662                         return -EINTR;
 663                 }
 664         }
 665
 666         fsl_lpspi_reset(fsl_lpspi);
 667
 668         return 0;
 669 }
 670
 671 static void fsl_lpspi_dma_exit(struct spi_controller *controller)
 672 {
 673         if (controller->dma_rx) {
 674                 dma_release_channel(controller->dma_rx);
 675                 controller->dma_rx = NULL;
 676         }
 677
 678         if (controller->dma_tx) {
 679                 dma_release_channel(controller->dma_tx);
 680                 controller->dma_tx = NULL;
 681         }
 682 }
 683
 684 static int fsl_lpspi_dma_init(struct device *dev,
 685                               struct fsl_lpspi_data *fsl_lpspi,
 686                               struct spi_controller *controller)
 687 {
 688         int ret;
 689
 690         /* Prepare for TX DMA: */
 691         controller->dma_tx = dma_request_chan(dev, "tx");
 692         if (IS_ERR(controller->dma_tx)) {
 693                 ret = PTR_ERR(controller->dma_tx);
 694                 dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
 695                 controller->dma_tx = NULL;
 696                 goto err;
 697         }
 698
 699         /* Prepare for RX DMA: */
 700         controller->dma_rx = dma_request_chan(dev, "rx");
 701         if (IS_ERR(controller->dma_rx)) {
 702                 ret = PTR_ERR(controller->dma_rx);
 703                 dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
 704                 controller->dma_rx = NULL;
 705                 goto err;
 706         }
 707
 708         init_completion(&fsl_lpspi->dma_rx_completion);
 709         init_completion(&fsl_lpspi->dma_tx_completion);
 710         controller->can_dma = fsl_lpspi_can_dma;
 711         controller->max_dma_len = FSL_LPSPI_MAX_EDMA_BYTES;
 712
 713         return 0;
 714 err:
 715         fsl_lpspi_dma_exit(controller);
 716         return ret;
 717 }
 718
 719 static int fsl_lpspi_pio_transfer(struct spi_controller *controller,
 720                                   struct spi_transfer *t)
 721 {
 722         struct fsl_lpspi_data *fsl_lpspi =
 723                                 spi_controller_get_devdata(controller);
 724         int ret;
 725
 726         fsl_lpspi->tx_buf = t->tx_buf;
 727         fsl_lpspi->rx_buf = t->rx_buf;
 728         fsl_lpspi->remain = t->len;
 729
 730         reinit_completion(&fsl_lpspi->xfer_done);
 731         fsl_lpspi->target_aborted = false;
 732
 733         fsl_lpspi_write_tx_fifo(fsl_lpspi);
 734
 735         ret = fsl_lpspi_wait_for_completion(controller);
 736         if (ret)
 737                 return ret;
 738
 739         fsl_lpspi_reset(fsl_lpspi);
 740
 741         return 0;
 742 }
 743
 744 static int fsl_lpspi_transfer_one(struct spi_controller *controller,
 745                                   struct spi_device *spi,
 746                                   struct spi_transfer *t)
 747 {
 748         struct fsl_lpspi_data *fsl_lpspi =
 749                                         spi_controller_get_devdata(controller);
 750         int ret;
 751
 752         fsl_lpspi->is_first_byte = true;
 753         ret = fsl_lpspi_setup_transfer(controller, spi, t);
 754         if (ret < 0)
 755                 return ret;
 756
 757         t->effective_speed_hz = fsl_lpspi->config.effective_speed_hz;
 758
 759         fsl_lpspi_set_cmd(fsl_lpspi);
 760         fsl_lpspi->is_first_byte = false;
 761
 762         if (fsl_lpspi->usedma)
 763                 ret = fsl_lpspi_dma_transfer(controller, fsl_lpspi, t);
 764         else
 765                 ret = fsl_lpspi_pio_transfer(controller, t);
 766         if (ret < 0)
 767                 return ret;
 768
 769         return 0;
 770 }
 771
 772 static irqreturn_t fsl_lpspi_isr(int irq, void *dev_id)
 773 {
 774         u32 temp_SR, temp_IER;
 775         struct fsl_lpspi_data *fsl_lpspi = dev_id;
 776
 777         temp_IER = readl(fsl_lpspi->base + IMX7ULP_IER);
 778         fsl_lpspi_intctrl(fsl_lpspi, 0);
 779         temp_SR = readl(fsl_lpspi->base + IMX7ULP_SR);
 780
 781         fsl_lpspi_read_rx_fifo(fsl_lpspi);
 782
 783         if ((temp_SR & SR_TDF) && (temp_IER & IER_TDIE)) {
 784                 fsl_lpspi_write_tx_fifo(fsl_lpspi);
 785                 return IRQ_HANDLED;
 786         }
 787
 788         if (temp_SR & SR_MBF ||
 789             readl(fsl_lpspi->base + IMX7ULP_FSR) & FSR_TXCOUNT) {
 790                 writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR);
 791                 fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE);
 792                 return IRQ_HANDLED;
 793         }
 794
 795         if (temp_SR & SR_FCF && (temp_IER & IER_FCIE)) {
 796                 writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR);
 797                 complete(&fsl_lpspi->xfer_done);
 798                 return IRQ_HANDLED;
 799         }
 800
 801         return IRQ_NONE;
 802 }
 803
 804 #ifdef CONFIG_PM
 805 static int fsl_lpspi_runtime_resume(struct device *dev)
 806 {
 807         struct spi_controller *controller = dev_get_drvdata(dev);
 808         struct fsl_lpspi_data *fsl_lpspi;
 809         int ret;
 810
 811         fsl_lpspi = spi_controller_get_devdata(controller);
 812
 813         ret = clk_prepare_enable(fsl_lpspi->clk_per);
 814         if (ret)
 815                 return ret;
 816
 817         ret = clk_prepare_enable(fsl_lpspi->clk_ipg);
 818         if (ret) {
 819                 clk_disable_unprepare(fsl_lpspi->clk_per);
 820                 return ret;
 821         }
 822
 823         return 0;
 824 }
 825
 826 static int fsl_lpspi_runtime_suspend(struct device *dev)
 827 {
 828         struct spi_controller *controller = dev_get_drvdata(dev);
 829         struct fsl_lpspi_data *fsl_lpspi;
 830
 831         fsl_lpspi = spi_controller_get_devdata(controller);
 832
 833         clk_disable_unprepare(fsl_lpspi->clk_per);
 834         clk_disable_unprepare(fsl_lpspi->clk_ipg);
 835
 836         return 0;
 837 }
 838 #endif
 839
 840 static int fsl_lpspi_init_rpm(struct fsl_lpspi_data *fsl_lpspi)
 841 {
 842         struct device *dev = fsl_lpspi->dev;
 843
 844         pm_runtime_enable(dev);
 845         pm_runtime_set_autosuspend_delay(dev, FSL_LPSPI_RPM_TIMEOUT);
 846         pm_runtime_use_autosuspend(dev);
 847
 848         return 0;
 849 }
 850
 851 static int fsl_lpspi_probe(struct platform_device *pdev)
 852 {
 853         const struct fsl_lpspi_devtype_data *devtype_data;
 854         struct fsl_lpspi_data *fsl_lpspi;
 855         struct spi_controller *controller;
 856         struct resource *res;
 857         int ret, irq;
 858         u32 num_cs;
 859         u32 temp;
 860         bool is_target;
 861
 862         devtype_data = of_device_get_match_data(&pdev->dev);
 863         if (!devtype_data)
 864                 return -ENODEV;
 865
 866         is_target = of_property_read_bool((&pdev->dev)->of_node, "spi-slave");
 867         if (is_target)
 868                 controller = devm_spi_alloc_target(&pdev->dev,
 869                                                    sizeof(struct fsl_lpspi_data));
 870         else
 871                 controller = devm_spi_alloc_host(&pdev->dev,
 872                                                  sizeof(struct fsl_lpspi_data));
 873
 874         if (!controller)
 875                 return -ENOMEM;
 876
 877         platform_set_drvdata(pdev, controller);
 878
 879         fsl_lpspi = spi_controller_get_devdata(controller);
 880         fsl_lpspi->dev = &pdev->dev;
 881         fsl_lpspi->is_target = is_target;
 882         fsl_lpspi->is_only_cs1 = of_property_read_bool((&pdev->dev)->of_node,
 883                                                 "fsl,spi-only-use-cs1-sel");
 884         fsl_lpspi->devtype_data = devtype_data;
 885
 886         init_completion(&fsl_lpspi->xfer_done);
 887
 888         fsl_lpspi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 889         if (IS_ERR(fsl_lpspi->base)) {
 890                 ret = PTR_ERR(fsl_lpspi->base);
 891                 return ret;
 892         }
 893         fsl_lpspi->base_phys = res->start;
 894
 895         irq = platform_get_irq(pdev, 0);
 896         if (irq < 0) {
 897                 ret = irq;
 898                 return ret;
 899         }
 900
 901         ret = devm_request_irq(&pdev->dev, irq, fsl_lpspi_isr, IRQF_NO_AUTOEN,
 902                                dev_name(&pdev->dev), fsl_lpspi);
 903         if (ret) {
 904                 dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
 905                 return ret;
 906         }
 907
 908         fsl_lpspi->clk_per = devm_clk_get(&pdev->dev, "per");
 909         if (IS_ERR(fsl_lpspi->clk_per)) {
 910                 ret = PTR_ERR(fsl_lpspi->clk_per);
 911                 return ret;
 912         }
 913
 914         fsl_lpspi->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
 915         if (IS_ERR(fsl_lpspi->clk_ipg)) {
 916                 ret = PTR_ERR(fsl_lpspi->clk_ipg);
 917                 return ret;
 918         }
 919
 920         /* enable the clock */
 921         ret = fsl_lpspi_init_rpm(fsl_lpspi);
 922         if (ret)
 923                 return ret;
 924
 925         ret = pm_runtime_get_sync(fsl_lpspi->dev);
 926         if (ret < 0) {
 927                 dev_err(fsl_lpspi->dev, "failed to enable clock\n");
 928                 goto out_pm_get;
 929         }
 930
 931         temp = readl(fsl_lpspi->base + IMX7ULP_PARAM);
 932         fsl_lpspi->txfifosize = 1 << (temp & 0x0f);
 933         fsl_lpspi->rxfifosize = 1 << ((temp >> 8) & 0x0f);
 934         if (of_property_read_u32((&pdev->dev)->of_node, "num-cs",
 935                                  &num_cs)) {
 936                 if (of_device_is_compatible(pdev->dev.of_node, "fsl,imx93-spi"))
 937                         num_cs = ((temp >> 16) & 0xf);
 938                 else
 939                         num_cs = 1;
 940         }
 941
 942         controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
 943         controller->transfer_one = fsl_lpspi_transfer_one;
 944         controller->prepare_transfer_hardware = lpspi_prepare_xfer_hardware;
 945         controller->unprepare_transfer_hardware = lpspi_unprepare_xfer_hardware;
 946         controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 947         controller->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
 948         controller->dev.of_node = pdev->dev.of_node;
 949         controller->bus_num = pdev->id;
 950         controller->num_chipselect = num_cs;
 951         controller->target_abort = fsl_lpspi_target_abort;
 952         if (!fsl_lpspi->is_target)
 953                 controller->use_gpio_descriptors = true;
 954
 955         ret = fsl_lpspi_dma_init(&pdev->dev, fsl_lpspi, controller);
 956         if (ret == -EPROBE_DEFER)
 957                 goto out_pm_get;
 958         if (ret < 0) {
 959                 dev_warn(&pdev->dev, "dma setup error %d, use pio\n", ret);
 960                 enable_irq(irq);
 961         }
 962
 963         ret = devm_spi_register_controller(&pdev->dev, controller);
 964         if (ret < 0) {
 965                 dev_err_probe(&pdev->dev, ret, "spi_register_controller error\n");
 966                 goto free_dma;
 967         }
 968
 969         pm_runtime_mark_last_busy(fsl_lpspi->dev);
 970         pm_runtime_put_autosuspend(fsl_lpspi->dev);
 971
 972         return 0;
 973
 974 free_dma:
 975         fsl_lpspi_dma_exit(controller);
 976 out_pm_get:
 977         pm_runtime_dont_use_autosuspend(fsl_lpspi->dev);
 978         pm_runtime_put_sync(fsl_lpspi->dev);
 979         pm_runtime_disable(fsl_lpspi->dev);
 980
 981         return ret;
 982 }
 983
 984 static void fsl_lpspi_remove(struct platform_device *pdev)
 985 {
 986         struct spi_controller *controller = platform_get_drvdata(pdev);
 987         struct fsl_lpspi_data *fsl_lpspi =
 988                                 spi_controller_get_devdata(controller);
 989
 990         fsl_lpspi_dma_exit(controller);
 991
 992         pm_runtime_dont_use_autosuspend(fsl_lpspi->dev);
 993         pm_runtime_disable(fsl_lpspi->dev);
 994 }
 995
 996 static int fsl_lpspi_suspend(struct device *dev)
 997 {
 998         pinctrl_pm_select_sleep_state(dev);
 999         return pm_runtime_force_suspend(dev);
1000 }
1001
1002 static int fsl_lpspi_resume(struct device *dev)
1003 {
1004         int ret;
1005
1006         ret = pm_runtime_force_resume(dev);
1007         if (ret) {
1008                 dev_err(dev, "Error in resume: %d\n", ret);
1009                 return ret;
1010         }
1011
1012         pinctrl_pm_select_default_state(dev);
1013
1014         return 0;
1015 }
1016
1017 static const struct dev_pm_ops fsl_lpspi_pm_ops = {
1018         SET_RUNTIME_PM_OPS(fsl_lpspi_runtime_suspend,
1019                                 fsl_lpspi_runtime_resume, NULL)
1020         SYSTEM_SLEEP_PM_OPS(fsl_lpspi_suspend, fsl_lpspi_resume)
1021 };
1022
1023 static struct platform_driver fsl_lpspi_driver = {
1024         .driver = {
1025                 .name = DRIVER_NAME,
1026                 .of_match_table = fsl_lpspi_dt_ids,
1027                 .pm = pm_ptr(&fsl_lpspi_pm_ops),
1028         },
1029         .probe = fsl_lpspi_probe,
1030         .remove = fsl_lpspi_remove,
1031 };
1032 module_platform_driver(fsl_lpspi_driver);
1033
1034 MODULE_DESCRIPTION("LPSPI Controller driver");
1035 MODULE_AUTHOR("Gao Pan <[email protected]>");
1036 MODULE_LICENSE("GPL");