drivers/spi/spi-imx.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 // Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   3 // Copyright (C) 2008 Juergen Beisert
   4
   5 #include <linux/clk.h>
   6 #include <linux/completion.h>
   7 #include <linux/delay.h>
   8 #include <linux/dmaengine.h>
   9 #include <linux/dma-mapping.h>
  10 #include <linux/err.h>
  11 #include <linux/gpio.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/io.h>
  14 #include <linux/irq.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/slab.h>
  19 #include <linux/spi/spi.h>
  20 #include <linux/spi/spi_bitbang.h>
  21 #include <linux/types.h>
  22 #include <linux/of.h>
  23 #include <linux/of_device.h>
  24 #include <linux/of_gpio.h>
  25
  26 #include <linux/platform_data/dma-imx.h>
  27 #include <linux/platform_data/spi-imx.h>
  28
  29 #define DRIVER_NAME "spi_imx"
  30
  31 #define MXC_CSPIRXDATA          0x00
  32 #define MXC_CSPITXDATA          0x04
  33 #define MXC_CSPICTRL            0x08
  34 #define MXC_CSPIINT             0x0c
  35 #define MXC_RESET               0x1c
  36
  37 /* generic defines to abstract from the different register layouts */
  38 #define MXC_INT_RR      (1 << 0) /* Receive data ready interrupt */
  39 #define MXC_INT_TE      (1 << 1) /* Transmit FIFO empty interrupt */
  40 #define MXC_INT_RDR     BIT(4) /* Receive date threshold interrupt */
  41
  42 /* The maximum  bytes that a sdma BD can transfer.*/
  43 #define MAX_SDMA_BD_BYTES  (1 << 15)
  44 #define MX51_ECSPI_CTRL_MAX_BURST       512
  45 /* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
  46 #define MX53_MAX_TRANSFER_BYTES         512
  47
  48 enum spi_imx_devtype {
  49         IMX1_CSPI,
  50         IMX21_CSPI,
  51         IMX27_CSPI,
  52         IMX31_CSPI,
  53         IMX35_CSPI,     /* CSPI on all i.mx except above */
  54         IMX51_ECSPI,    /* ECSPI on i.mx51 */
  55         IMX53_ECSPI,    /* ECSPI on i.mx53 and later */
  56 };
  57
  58 struct spi_imx_data;
  59
  60 struct spi_imx_devtype_data {
  61         void (*intctrl)(struct spi_imx_data *, int);
  62         int (*config)(struct spi_device *);
  63         void (*trigger)(struct spi_imx_data *);
  64         int (*rx_available)(struct spi_imx_data *);
  65         void (*reset)(struct spi_imx_data *);
  66         void (*disable)(struct spi_imx_data *);
  67         bool has_dmamode;
  68         bool has_slavemode;
  69         unsigned int fifo_size;
  70         bool dynamic_burst;
  71         enum spi_imx_devtype devtype;
  72 };
  73
  74 struct spi_imx_data {
  75         struct spi_bitbang bitbang;
  76         struct device *dev;
  77
  78         struct completion xfer_done;
  79         void __iomem *base;
  80         unsigned long base_phys;
  81
  82         struct clk *clk_per;
  83         struct clk *clk_ipg;
  84         unsigned long spi_clk;
  85         unsigned int spi_bus_clk;
  86
  87         unsigned int speed_hz;
  88         unsigned int bits_per_word;
  89         unsigned int spi_drctl;
  90
  91         unsigned int count, remainder;
  92         void (*tx)(struct spi_imx_data *);
  93         void (*rx)(struct spi_imx_data *);
  94         void *rx_buf;
  95         const void *tx_buf;
  96         unsigned int txfifo; /* number of words pushed in tx FIFO */
  97         unsigned int dynamic_burst;
  98
  99         /* Slave mode */
 100         bool slave_mode;
 101         bool slave_aborted;
 102         unsigned int slave_burst;
 103
 104         /* DMA */
 105         bool usedma;
 106         u32 wml;
 107         struct completion dma_rx_completion;
 108         struct completion dma_tx_completion;
 109
 110         const struct spi_imx_devtype_data *devtype_data;
 111 };
 112
 113 static inline int is_imx27_cspi(struct spi_imx_data *d)
 114 {
 115         return d->devtype_data->devtype == IMX27_CSPI;
 116 }
 117
 118 static inline int is_imx35_cspi(struct spi_imx_data *d)
 119 {
 120         return d->devtype_data->devtype == IMX35_CSPI;
 121 }
 122
 123 static inline int is_imx51_ecspi(struct spi_imx_data *d)
 124 {
 125         return d->devtype_data->devtype == IMX51_ECSPI;
 126 }
 127
 128 static inline int is_imx53_ecspi(struct spi_imx_data *d)
 129 {
 130         return d->devtype_data->devtype == IMX53_ECSPI;
 131 }
 132
 133 #define MXC_SPI_BUF_RX(type)                                            \
 134 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)         \
 135 {                                                                       \
 136         unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);       \
 137                                                                         \
 138         if (spi_imx->rx_buf) {                                          \
 139                 *(type *)spi_imx->rx_buf = val;                         \
 140                 spi_imx->rx_buf += sizeof(type);                        \
 141         }                                                               \
 142                                                                         \
 143         spi_imx->remainder -= sizeof(type);                             \
 144 }
 145
 146 #define MXC_SPI_BUF_TX(type)                                            \
 147 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)         \
 148 {                                                                       \
 149         type val = 0;                                                   \
 150                                                                         \
 151         if (spi_imx->tx_buf) {                                          \
 152                 val = *(type *)spi_imx->tx_buf;                         \
 153                 spi_imx->tx_buf += sizeof(type);                        \
 154         }                                                               \
 155                                                                         \
 156         spi_imx->count -= sizeof(type);                                 \
 157                                                                         \
 158         writel(val, spi_imx->base + MXC_CSPITXDATA);                    \
 159 }
 160
 161 MXC_SPI_BUF_RX(u8)
 162 MXC_SPI_BUF_TX(u8)
 163 MXC_SPI_BUF_RX(u16)
 164 MXC_SPI_BUF_TX(u16)
 165 MXC_SPI_BUF_RX(u32)
 166 MXC_SPI_BUF_TX(u32)
 167
 168 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 169  * (which is currently not the case in this driver)
 170  */
 171 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 172         256, 384, 512, 768, 1024};
 173
 174 /* MX21, MX27 */
 175 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 176                 unsigned int fspi, unsigned int max, unsigned int *fres)
 177 {
 178         int i;
 179
 180         for (i = 2; i < max; i++)
 181                 if (fspi * mxc_clkdivs[i] >= fin)
 182                         break;
 183
 184         *fres = fin / mxc_clkdivs[i];
 185         return i;
 186 }
 187
 188 /* MX1, MX31, MX35, MX51 CSPI */
 189 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 190                 unsigned int fspi, unsigned int *fres)
 191 {
 192         int i, div = 4;
 193
 194         for (i = 0; i < 7; i++) {
 195                 if (fspi * div >= fin)
 196                         goto out;
 197                 div <<= 1;
 198         }
 199
 200 out:
 201         *fres = fin / div;
 202         return i;
 203 }
 204
 205 static int spi_imx_bytes_per_word(const int bits_per_word)
 206 {
 207         if (bits_per_word <= 8)
 208                 return 1;
 209         else if (bits_per_word <= 16)
 210                 return 2;
 211         else
 212                 return 4;
 213 }
 214
 215 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 216                          struct spi_transfer *transfer)
 217 {
 218         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 219         unsigned int bytes_per_word, i;
 220
 221         if (!master->dma_rx)
 222                 return false;
 223
 224         if (spi_imx->slave_mode)
 225                 return false;
 226
 227         bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
 228
 229         for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
 230                 if (!(transfer->len % (i * bytes_per_word)))
 231                         break;
 232         }
 233
 234         spi_imx->wml = i;
 235         spi_imx->dynamic_burst = 0;
 236
 237         return true;
 238 }
 239
 240 #define MX51_ECSPI_CTRL         0x08
 241 #define MX51_ECSPI_CTRL_ENABLE          (1 <<  0)
 242 #define MX51_ECSPI_CTRL_XCH             (1 <<  2)
 243 #define MX51_ECSPI_CTRL_SMC             (1 << 3)
 244 #define MX51_ECSPI_CTRL_MODE_MASK       (0xf << 4)
 245 #define MX51_ECSPI_CTRL_DRCTL(drctl)    ((drctl) << 16)
 246 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET  8
 247 #define MX51_ECSPI_CTRL_PREDIV_OFFSET   12
 248 #define MX51_ECSPI_CTRL_CS(cs)          ((cs) << 18)
 249 #define MX51_ECSPI_CTRL_BL_OFFSET       20
 250 #define MX51_ECSPI_CTRL_BL_MASK         (0xfff << 20)
 251
 252 #define MX51_ECSPI_CONFIG       0x0c
 253 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)   (1 << ((cs) +  0))
 254 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)   (1 << ((cs) +  4))
 255 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)   (1 << ((cs) +  8))
 256 #define MX51_ECSPI_CONFIG_SSBPOL(cs)    (1 << ((cs) + 12))
 257 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)   (1 << ((cs) + 20))
 258
 259 #define MX51_ECSPI_INT          0x10
 260 #define MX51_ECSPI_INT_TEEN             (1 <<  0)
 261 #define MX51_ECSPI_INT_RREN             (1 <<  3)
 262 #define MX51_ECSPI_INT_RDREN            (1 <<  4)
 263
 264 #define MX51_ECSPI_DMA      0x14
 265 #define MX51_ECSPI_DMA_TX_WML(wml)      ((wml) & 0x3f)
 266 #define MX51_ECSPI_DMA_RX_WML(wml)      (((wml) & 0x3f) << 16)
 267 #define MX51_ECSPI_DMA_RXT_WML(wml)     (((wml) & 0x3f) << 24)
 268
 269 #define MX51_ECSPI_DMA_TEDEN            (1 << 7)
 270 #define MX51_ECSPI_DMA_RXDEN            (1 << 23)
 271 #define MX51_ECSPI_DMA_RXTDEN           (1 << 31)
 272
 273 #define MX51_ECSPI_STAT         0x18
 274 #define MX51_ECSPI_STAT_RR              (1 <<  3)
 275
 276 #define MX51_ECSPI_TESTREG      0x20
 277 #define MX51_ECSPI_TESTREG_LBC  BIT(31)
 278
 279 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
 280 {
 281         unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
 282 #ifdef __LITTLE_ENDIAN
 283         unsigned int bytes_per_word;
 284 #endif
 285
 286         if (spi_imx->rx_buf) {
 287 #ifdef __LITTLE_ENDIAN
 288                 bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 289                 if (bytes_per_word == 1)
 290                         val = cpu_to_be32(val);
 291                 else if (bytes_per_word == 2)
 292                         val = (val << 16) | (val >> 16);
 293 #endif
 294                 *(u32 *)spi_imx->rx_buf = val;
 295                 spi_imx->rx_buf += sizeof(u32);
 296         }
 297
 298         spi_imx->remainder -= sizeof(u32);
 299 }
 300
 301 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
 302 {
 303         int unaligned;
 304         u32 val;
 305
 306         unaligned = spi_imx->remainder % 4;
 307
 308         if (!unaligned) {
 309                 spi_imx_buf_rx_swap_u32(spi_imx);
 310                 return;
 311         }
 312
 313         if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 314                 spi_imx_buf_rx_u16(spi_imx);
 315                 return;
 316         }
 317
 318         val = readl(spi_imx->base + MXC_CSPIRXDATA);
 319
 320         while (unaligned--) {
 321                 if (spi_imx->rx_buf) {
 322                         *(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
 323                         spi_imx->rx_buf++;
 324                 }
 325                 spi_imx->remainder--;
 326         }
 327 }
 328
 329 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
 330 {
 331         u32 val = 0;
 332 #ifdef __LITTLE_ENDIAN
 333         unsigned int bytes_per_word;
 334 #endif
 335
 336         if (spi_imx->tx_buf) {
 337                 val = *(u32 *)spi_imx->tx_buf;
 338                 spi_imx->tx_buf += sizeof(u32);
 339         }
 340
 341         spi_imx->count -= sizeof(u32);
 342 #ifdef __LITTLE_ENDIAN
 343         bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 344
 345         if (bytes_per_word == 1)
 346                 val = cpu_to_be32(val);
 347         else if (bytes_per_word == 2)
 348                 val = (val << 16) | (val >> 16);
 349 #endif
 350         writel(val, spi_imx->base + MXC_CSPITXDATA);
 351 }
 352
 353 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
 354 {
 355         int unaligned;
 356         u32 val = 0;
 357
 358         unaligned = spi_imx->count % 4;
 359
 360         if (!unaligned) {
 361                 spi_imx_buf_tx_swap_u32(spi_imx);
 362                 return;
 363         }
 364
 365         if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 366                 spi_imx_buf_tx_u16(spi_imx);
 367                 return;
 368         }
 369
 370         while (unaligned--) {
 371                 if (spi_imx->tx_buf) {
 372                         val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
 373                         spi_imx->tx_buf++;
 374                 }
 375                 spi_imx->count--;
 376         }
 377
 378         writel(val, spi_imx->base + MXC_CSPITXDATA);
 379 }
 380
 381 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
 382 {
 383         u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
 384
 385         if (spi_imx->rx_buf) {
 386                 int n_bytes = spi_imx->slave_burst % sizeof(val);
 387
 388                 if (!n_bytes)
 389                         n_bytes = sizeof(val);
 390
 391                 memcpy(spi_imx->rx_buf,
 392                        ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
 393
 394                 spi_imx->rx_buf += n_bytes;
 395                 spi_imx->slave_burst -= n_bytes;
 396         }
 397
 398         spi_imx->remainder -= sizeof(u32);
 399 }
 400
 401 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
 402 {
 403         u32 val = 0;
 404         int n_bytes = spi_imx->count % sizeof(val);
 405
 406         if (!n_bytes)
 407                 n_bytes = sizeof(val);
 408
 409         if (spi_imx->tx_buf) {
 410                 memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
 411                        spi_imx->tx_buf, n_bytes);
 412                 val = cpu_to_be32(val);
 413                 spi_imx->tx_buf += n_bytes;
 414         }
 415
 416         spi_imx->count -= n_bytes;
 417
 418         writel(val, spi_imx->base + MXC_CSPITXDATA);
 419 }
 420
 421 /* MX51 eCSPI */
 422 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 423                                       unsigned int fspi, unsigned int *fres)
 424 {
 425         /*
 426          * there are two 4-bit dividers, the pre-divider divides by
 427          * $pre, the post-divider by 2^$post
 428          */
 429         unsigned int pre, post;
 430         unsigned int fin = spi_imx->spi_clk;
 431
 432         if (unlikely(fspi > fin))
 433                 return 0;
 434
 435         post = fls(fin) - fls(fspi);
 436         if (fin > fspi << post)
 437                 post++;
 438
 439         /* now we have: (fin <= fspi << post) with post being minimal */
 440
 441         post = max(4U, post) - 4;
 442         if (unlikely(post > 0xf)) {
 443                 dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 444                                 fspi, fin);
 445                 return 0xff;
 446         }
 447
 448         pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 449
 450         dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 451                         __func__, fin, fspi, post, pre);
 452
 453         /* Resulting frequency for the SCLK line. */
 454         *fres = (fin / (pre + 1)) >> post;
 455
 456         return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 457                 (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 458 }
 459
 460 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 461 {
 462         unsigned val = 0;
 463
 464         if (enable & MXC_INT_TE)
 465                 val |= MX51_ECSPI_INT_TEEN;
 466
 467         if (enable & MXC_INT_RR)
 468                 val |= MX51_ECSPI_INT_RREN;
 469
 470         if (enable & MXC_INT_RDR)
 471                 val |= MX51_ECSPI_INT_RDREN;
 472
 473         writel(val, spi_imx->base + MX51_ECSPI_INT);
 474 }
 475
 476 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 477 {
 478         u32 reg;
 479
 480         reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 481         reg |= MX51_ECSPI_CTRL_XCH;
 482         writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 483 }
 484
 485 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
 486 {
 487         u32 ctrl;
 488
 489         ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 490         ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
 491         writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 492 }
 493
 494 static int mx51_ecspi_config(struct spi_device *spi)
 495 {
 496         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 497         u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 498         u32 clk = spi_imx->speed_hz, delay, reg;
 499         u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 500
 501         /* set Master or Slave mode */
 502         if (spi_imx->slave_mode)
 503                 ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
 504         else
 505                 ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 506
 507         /*
 508          * Enable SPI_RDY handling (falling edge/level triggered).
 509          */
 510         if (spi->mode & SPI_READY)
 511                 ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
 512
 513         /* set clock speed */
 514         ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->speed_hz, &clk);
 515         spi_imx->spi_bus_clk = clk;
 516
 517         /* set chip select to use */
 518         ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
 519
 520         if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 521                 ctrl |= (spi_imx->slave_burst * 8 - 1)
 522                         << MX51_ECSPI_CTRL_BL_OFFSET;
 523         else
 524                 ctrl |= (spi_imx->bits_per_word - 1)
 525                         << MX51_ECSPI_CTRL_BL_OFFSET;
 526
 527         /*
 528          * eCSPI burst completion by Chip Select signal in Slave mode
 529          * is not functional for imx53 Soc, config SPI burst completed when
 530          * BURST_LENGTH + 1 bits are received
 531          */
 532         if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 533                 cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 534         else
 535                 cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 536
 537         if (spi->mode & SPI_CPHA)
 538                 cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 539         else
 540                 cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 541
 542         if (spi->mode & SPI_CPOL) {
 543                 cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 544                 cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 545         } else {
 546                 cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 547                 cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 548         }
 549         if (spi->mode & SPI_CS_HIGH)
 550                 cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 551         else
 552                 cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 553
 554         if (spi_imx->usedma)
 555                 ctrl |= MX51_ECSPI_CTRL_SMC;
 556
 557         /* CTRL register always go first to bring out controller from reset */
 558         writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 559
 560         reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 561         if (spi->mode & SPI_LOOP)
 562                 reg |= MX51_ECSPI_TESTREG_LBC;
 563         else
 564                 reg &= ~MX51_ECSPI_TESTREG_LBC;
 565         writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
 566
 567         writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 568
 569         /*
 570          * Wait until the changes in the configuration register CONFIGREG
 571          * propagate into the hardware. It takes exactly one tick of the
 572          * SCLK clock, but we will wait two SCLK clock just to be sure. The
 573          * effect of the delay it takes for the hardware to apply changes
 574          * is noticable if the SCLK clock run very slow. In such a case, if
 575          * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 576          * be asserted before the SCLK polarity changes, which would disrupt
 577          * the SPI communication as the device on the other end would consider
 578          * the change of SCLK polarity as a clock tick already.
 579          */
 580         delay = (2 * 1000000) / clk;
 581         if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
 582                 udelay(delay);
 583         else                    /* SCLK is _very_ slow */
 584                 usleep_range(delay, delay + 10);
 585
 586         /*
 587          * Configure the DMA register: setup the watermark
 588          * and enable DMA request.
 589          */
 590
 591         writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) |
 592                 MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
 593                 MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 594                 MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 595                 MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 596
 597         return 0;
 598 }
 599
 600 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 601 {
 602         return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 603 }
 604
 605 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 606 {
 607         /* drain receive buffer */
 608         while (mx51_ecspi_rx_available(spi_imx))
 609                 readl(spi_imx->base + MXC_CSPIRXDATA);
 610 }
 611
 612 #define MX31_INTREG_TEEN        (1 << 0)
 613 #define MX31_INTREG_RREN        (1 << 3)
 614
 615 #define MX31_CSPICTRL_ENABLE    (1 << 0)
 616 #define MX31_CSPICTRL_MASTER    (1 << 1)
 617 #define MX31_CSPICTRL_XCH       (1 << 2)
 618 #define MX31_CSPICTRL_SMC       (1 << 3)
 619 #define MX31_CSPICTRL_POL       (1 << 4)
 620 #define MX31_CSPICTRL_PHA       (1 << 5)
 621 #define MX31_CSPICTRL_SSCTL     (1 << 6)
 622 #define MX31_CSPICTRL_SSPOL     (1 << 7)
 623 #define MX31_CSPICTRL_BC_SHIFT  8
 624 #define MX35_CSPICTRL_BL_SHIFT  20
 625 #define MX31_CSPICTRL_CS_SHIFT  24
 626 #define MX35_CSPICTRL_CS_SHIFT  12
 627 #define MX31_CSPICTRL_DR_SHIFT  16
 628
 629 #define MX31_CSPI_DMAREG        0x10
 630 #define MX31_DMAREG_RH_DEN      (1<<4)
 631 #define MX31_DMAREG_TH_DEN      (1<<1)
 632
 633 #define MX31_CSPISTATUS         0x14
 634 #define MX31_STATUS_RR          (1 << 3)
 635
 636 #define MX31_CSPI_TESTREG       0x1C
 637 #define MX31_TEST_LBC           (1 << 14)
 638
 639 /* These functions also work for the i.MX35, but be aware that
 640  * the i.MX35 has a slightly different register layout for bits
 641  * we do not use here.
 642  */
 643 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 644 {
 645         unsigned int val = 0;
 646
 647         if (enable & MXC_INT_TE)
 648                 val |= MX31_INTREG_TEEN;
 649         if (enable & MXC_INT_RR)
 650                 val |= MX31_INTREG_RREN;
 651
 652         writel(val, spi_imx->base + MXC_CSPIINT);
 653 }
 654
 655 static void mx31_trigger(struct spi_imx_data *spi_imx)
 656 {
 657         unsigned int reg;
 658
 659         reg = readl(spi_imx->base + MXC_CSPICTRL);
 660         reg |= MX31_CSPICTRL_XCH;
 661         writel(reg, spi_imx->base + MXC_CSPICTRL);
 662 }
 663
 664 static int mx31_config(struct spi_device *spi)
 665 {
 666         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 667         unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 668         unsigned int clk;
 669
 670         reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->speed_hz, &clk) <<
 671                 MX31_CSPICTRL_DR_SHIFT;
 672         spi_imx->spi_bus_clk = clk;
 673
 674         if (is_imx35_cspi(spi_imx)) {
 675                 reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
 676                 reg |= MX31_CSPICTRL_SSCTL;
 677         } else {
 678                 reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
 679         }
 680
 681         if (spi->mode & SPI_CPHA)
 682                 reg |= MX31_CSPICTRL_PHA;
 683         if (spi->mode & SPI_CPOL)
 684                 reg |= MX31_CSPICTRL_POL;
 685         if (spi->mode & SPI_CS_HIGH)
 686                 reg |= MX31_CSPICTRL_SSPOL;
 687         if (!gpio_is_valid(spi->cs_gpio))
 688                 reg |= (spi->chip_select) <<
 689                         (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 690                                                   MX31_CSPICTRL_CS_SHIFT);
 691
 692         if (spi_imx->usedma)
 693                 reg |= MX31_CSPICTRL_SMC;
 694
 695         writel(reg, spi_imx->base + MXC_CSPICTRL);
 696
 697         reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
 698         if (spi->mode & SPI_LOOP)
 699                 reg |= MX31_TEST_LBC;
 700         else
 701                 reg &= ~MX31_TEST_LBC;
 702         writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
 703
 704         if (spi_imx->usedma) {
 705                 /* configure DMA requests when RXFIFO is half full and
 706                    when TXFIFO is half empty */
 707                 writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
 708                         spi_imx->base + MX31_CSPI_DMAREG);
 709         }
 710
 711         return 0;
 712 }
 713
 714 static int mx31_rx_available(struct spi_imx_data *spi_imx)
 715 {
 716         return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 717 }
 718
 719 static void mx31_reset(struct spi_imx_data *spi_imx)
 720 {
 721         /* drain receive buffer */
 722         while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 723                 readl(spi_imx->base + MXC_CSPIRXDATA);
 724 }
 725
 726 #define MX21_INTREG_RR          (1 << 4)
 727 #define MX21_INTREG_TEEN        (1 << 9)
 728 #define MX21_INTREG_RREN        (1 << 13)
 729
 730 #define MX21_CSPICTRL_POL       (1 << 5)
 731 #define MX21_CSPICTRL_PHA       (1 << 6)
 732 #define MX21_CSPICTRL_SSPOL     (1 << 8)
 733 #define MX21_CSPICTRL_XCH       (1 << 9)
 734 #define MX21_CSPICTRL_ENABLE    (1 << 10)
 735 #define MX21_CSPICTRL_MASTER    (1 << 11)
 736 #define MX21_CSPICTRL_DR_SHIFT  14
 737 #define MX21_CSPICTRL_CS_SHIFT  19
 738
 739 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 740 {
 741         unsigned int val = 0;
 742
 743         if (enable & MXC_INT_TE)
 744                 val |= MX21_INTREG_TEEN;
 745         if (enable & MXC_INT_RR)
 746                 val |= MX21_INTREG_RREN;
 747
 748         writel(val, spi_imx->base + MXC_CSPIINT);
 749 }
 750
 751 static void mx21_trigger(struct spi_imx_data *spi_imx)
 752 {
 753         unsigned int reg;
 754
 755         reg = readl(spi_imx->base + MXC_CSPICTRL);
 756         reg |= MX21_CSPICTRL_XCH;
 757         writel(reg, spi_imx->base + MXC_CSPICTRL);
 758 }
 759
 760 static int mx21_config(struct spi_device *spi)
 761 {
 762         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 763         unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 764         unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 765         unsigned int clk;
 766
 767         reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->speed_hz, max, &clk)
 768                 << MX21_CSPICTRL_DR_SHIFT;
 769         spi_imx->spi_bus_clk = clk;
 770
 771         reg |= spi_imx->bits_per_word - 1;
 772
 773         if (spi->mode & SPI_CPHA)
 774                 reg |= MX21_CSPICTRL_PHA;
 775         if (spi->mode & SPI_CPOL)
 776                 reg |= MX21_CSPICTRL_POL;
 777         if (spi->mode & SPI_CS_HIGH)
 778                 reg |= MX21_CSPICTRL_SSPOL;
 779         if (!gpio_is_valid(spi->cs_gpio))
 780                 reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
 781
 782         writel(reg, spi_imx->base + MXC_CSPICTRL);
 783
 784         return 0;
 785 }
 786
 787 static int mx21_rx_available(struct spi_imx_data *spi_imx)
 788 {
 789         return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 790 }
 791
 792 static void mx21_reset(struct spi_imx_data *spi_imx)
 793 {
 794         writel(1, spi_imx->base + MXC_RESET);
 795 }
 796
 797 #define MX1_INTREG_RR           (1 << 3)
 798 #define MX1_INTREG_TEEN         (1 << 8)
 799 #define MX1_INTREG_RREN         (1 << 11)
 800
 801 #define MX1_CSPICTRL_POL        (1 << 4)
 802 #define MX1_CSPICTRL_PHA        (1 << 5)
 803 #define MX1_CSPICTRL_XCH        (1 << 8)
 804 #define MX1_CSPICTRL_ENABLE     (1 << 9)
 805 #define MX1_CSPICTRL_MASTER     (1 << 10)
 806 #define MX1_CSPICTRL_DR_SHIFT   13
 807
 808 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 809 {
 810         unsigned int val = 0;
 811
 812         if (enable & MXC_INT_TE)
 813                 val |= MX1_INTREG_TEEN;
 814         if (enable & MXC_INT_RR)
 815                 val |= MX1_INTREG_RREN;
 816
 817         writel(val, spi_imx->base + MXC_CSPIINT);
 818 }
 819
 820 static void mx1_trigger(struct spi_imx_data *spi_imx)
 821 {
 822         unsigned int reg;
 823
 824         reg = readl(spi_imx->base + MXC_CSPICTRL);
 825         reg |= MX1_CSPICTRL_XCH;
 826         writel(reg, spi_imx->base + MXC_CSPICTRL);
 827 }
 828
 829 static int mx1_config(struct spi_device *spi)
 830 {
 831         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 832         unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 833         unsigned int clk;
 834
 835         reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->speed_hz, &clk) <<
 836                 MX1_CSPICTRL_DR_SHIFT;
 837         spi_imx->spi_bus_clk = clk;
 838
 839         reg |= spi_imx->bits_per_word - 1;
 840
 841         if (spi->mode & SPI_CPHA)
 842                 reg |= MX1_CSPICTRL_PHA;
 843         if (spi->mode & SPI_CPOL)
 844                 reg |= MX1_CSPICTRL_POL;
 845
 846         writel(reg, spi_imx->base + MXC_CSPICTRL);
 847
 848         return 0;
 849 }
 850
 851 static int mx1_rx_available(struct spi_imx_data *spi_imx)
 852 {
 853         return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 854 }
 855
 856 static void mx1_reset(struct spi_imx_data *spi_imx)
 857 {
 858         writel(1, spi_imx->base + MXC_RESET);
 859 }
 860
 861 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 862         .intctrl = mx1_intctrl,
 863         .config = mx1_config,
 864         .trigger = mx1_trigger,
 865         .rx_available = mx1_rx_available,
 866         .reset = mx1_reset,
 867         .fifo_size = 8,
 868         .has_dmamode = false,
 869         .dynamic_burst = false,
 870         .has_slavemode = false,
 871         .devtype = IMX1_CSPI,
 872 };
 873
 874 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 875         .intctrl = mx21_intctrl,
 876         .config = mx21_config,
 877         .trigger = mx21_trigger,
 878         .rx_available = mx21_rx_available,
 879         .reset = mx21_reset,
 880         .fifo_size = 8,
 881         .has_dmamode = false,
 882         .dynamic_burst = false,
 883         .has_slavemode = false,
 884         .devtype = IMX21_CSPI,
 885 };
 886
 887 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 888         /* i.mx27 cspi shares the functions with i.mx21 one */
 889         .intctrl = mx21_intctrl,
 890         .config = mx21_config,
 891         .trigger = mx21_trigger,
 892         .rx_available = mx21_rx_available,
 893         .reset = mx21_reset,
 894         .fifo_size = 8,
 895         .has_dmamode = false,
 896         .dynamic_burst = false,
 897         .has_slavemode = false,
 898         .devtype = IMX27_CSPI,
 899 };
 900
 901 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 902         .intctrl = mx31_intctrl,
 903         .config = mx31_config,
 904         .trigger = mx31_trigger,
 905         .rx_available = mx31_rx_available,
 906         .reset = mx31_reset,
 907         .fifo_size = 8,
 908         .has_dmamode = false,
 909         .dynamic_burst = false,
 910         .has_slavemode = false,
 911         .devtype = IMX31_CSPI,
 912 };
 913
 914 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 915         /* i.mx35 and later cspi shares the functions with i.mx31 one */
 916         .intctrl = mx31_intctrl,
 917         .config = mx31_config,
 918         .trigger = mx31_trigger,
 919         .rx_available = mx31_rx_available,
 920         .reset = mx31_reset,
 921         .fifo_size = 8,
 922         .has_dmamode = true,
 923         .dynamic_burst = false,
 924         .has_slavemode = false,
 925         .devtype = IMX35_CSPI,
 926 };
 927
 928 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 929         .intctrl = mx51_ecspi_intctrl,
 930         .config = mx51_ecspi_config,
 931         .trigger = mx51_ecspi_trigger,
 932         .rx_available = mx51_ecspi_rx_available,
 933         .reset = mx51_ecspi_reset,
 934         .fifo_size = 64,
 935         .has_dmamode = true,
 936         .dynamic_burst = true,
 937         .has_slavemode = true,
 938         .disable = mx51_ecspi_disable,
 939         .devtype = IMX51_ECSPI,
 940 };
 941
 942 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
 943         .intctrl = mx51_ecspi_intctrl,
 944         .config = mx51_ecspi_config,
 945         .trigger = mx51_ecspi_trigger,
 946         .rx_available = mx51_ecspi_rx_available,
 947         .reset = mx51_ecspi_reset,
 948         .fifo_size = 64,
 949         .has_dmamode = true,
 950         .has_slavemode = true,
 951         .disable = mx51_ecspi_disable,
 952         .devtype = IMX53_ECSPI,
 953 };
 954
 955 static const struct platform_device_id spi_imx_devtype[] = {
 956         {
 957                 .name = "imx1-cspi",
 958                 .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
 959         }, {
 960                 .name = "imx21-cspi",
 961                 .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
 962         }, {
 963                 .name = "imx27-cspi",
 964                 .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
 965         }, {
 966                 .name = "imx31-cspi",
 967                 .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
 968         }, {
 969                 .name = "imx35-cspi",
 970                 .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
 971         }, {
 972                 .name = "imx51-ecspi",
 973                 .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
 974         }, {
 975                 .name = "imx53-ecspi",
 976                 .driver_data = (kernel_ulong_t) &imx53_ecspi_devtype_data,
 977         }, {
 978                 /* sentinel */
 979         }
 980 };
 981
 982 static const struct of_device_id spi_imx_dt_ids[] = {
 983         { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
 984         { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
 985         { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
 986         { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
 987         { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
 988         { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
 989         { .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
 990         { /* sentinel */ }
 991 };
 992 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
 993
 994 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
 995 {
 996         int active = is_active != BITBANG_CS_INACTIVE;
 997         int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
 998
 999         if (spi->mode & SPI_NO_CS)
1000                 return;
1001
1002         if (!gpio_is_valid(spi->cs_gpio))
1003                 return;
1004
1005         gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active);
1006 }
1007
1008 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1009 {
1010         u32 ctrl;
1011
1012         ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1013         ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1014         ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1015         writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1016 }
1017
1018 static void spi_imx_push(struct spi_imx_data *spi_imx)
1019 {
1020         unsigned int burst_len, fifo_words;
1021
1022         if (spi_imx->dynamic_burst)
1023                 fifo_words = 4;
1024         else
1025                 fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1026         /*
1027          * Reload the FIFO when the remaining bytes to be transferred in the
1028          * current burst is 0. This only applies when bits_per_word is a
1029          * multiple of 8.
1030          */
1031         if (!spi_imx->remainder) {
1032                 if (spi_imx->dynamic_burst) {
1033
1034                         /* We need to deal unaligned data first */
1035                         burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1036
1037                         if (!burst_len)
1038                                 burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1039
1040                         spi_imx_set_burst_len(spi_imx, burst_len * 8);
1041
1042                         spi_imx->remainder = burst_len;
1043                 } else {
1044                         spi_imx->remainder = fifo_words;
1045                 }
1046         }
1047
1048         while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1049                 if (!spi_imx->count)
1050                         break;
1051                 if (spi_imx->dynamic_burst &&
1052                     spi_imx->txfifo >=  DIV_ROUND_UP(spi_imx->remainder,
1053                                                      fifo_words))
1054                         break;
1055                 spi_imx->tx(spi_imx);
1056                 spi_imx->txfifo++;
1057         }
1058
1059         if (!spi_imx->slave_mode)
1060                 spi_imx->devtype_data->trigger(spi_imx);
1061 }
1062
1063 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1064 {
1065         struct spi_imx_data *spi_imx = dev_id;
1066
1067         while (spi_imx->txfifo &&
1068                spi_imx->devtype_data->rx_available(spi_imx)) {
1069                 spi_imx->rx(spi_imx);
1070                 spi_imx->txfifo--;
1071         }
1072
1073         if (spi_imx->count) {
1074                 spi_imx_push(spi_imx);
1075                 return IRQ_HANDLED;
1076         }
1077
1078         if (spi_imx->txfifo) {
1079                 /* No data left to push, but still waiting for rx data,
1080                  * enable receive data available interrupt.
1081                  */
1082                 spi_imx->devtype_data->intctrl(
1083                                 spi_imx, MXC_INT_RR);
1084                 return IRQ_HANDLED;
1085         }
1086
1087         spi_imx->devtype_data->intctrl(spi_imx, 0);
1088         complete(&spi_imx->xfer_done);
1089
1090         return IRQ_HANDLED;
1091 }
1092
1093 static int spi_imx_dma_configure(struct spi_master *master)
1094 {
1095         int ret;
1096         enum dma_slave_buswidth buswidth;
1097         struct dma_slave_config rx = {}, tx = {};
1098         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1099
1100         switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1101         case 4:
1102                 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1103                 break;
1104         case 2:
1105                 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1106                 break;
1107         case 1:
1108                 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1109                 break;
1110         default:
1111                 return -EINVAL;
1112         }
1113
1114         tx.direction = DMA_MEM_TO_DEV;
1115         tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1116         tx.dst_addr_width = buswidth;
1117         tx.dst_maxburst = spi_imx->wml;
1118         ret = dmaengine_slave_config(master->dma_tx, &tx);
1119         if (ret) {
1120                 dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1121                 return ret;
1122         }
1123
1124         rx.direction = DMA_DEV_TO_MEM;
1125         rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1126         rx.src_addr_width = buswidth;
1127         rx.src_maxburst = spi_imx->wml;
1128         ret = dmaengine_slave_config(master->dma_rx, &rx);
1129         if (ret) {
1130                 dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1131                 return ret;
1132         }
1133
1134         return 0;
1135 }
1136
1137 static int spi_imx_setupxfer(struct spi_device *spi,
1138                                  struct spi_transfer *t)
1139 {
1140         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1141         int ret;
1142
1143         if (!t)
1144                 return 0;
1145
1146         spi_imx->bits_per_word = t->bits_per_word;
1147         spi_imx->speed_hz  = t->speed_hz;
1148
1149         /*
1150          * Initialize the functions for transfer. To transfer non byte-aligned
1151          * words, we have to use multiple word-size bursts, we can't use
1152          * dynamic_burst in that case.
1153          */
1154         if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1155             (spi_imx->bits_per_word == 8 ||
1156             spi_imx->bits_per_word == 16 ||
1157             spi_imx->bits_per_word == 32)) {
1158
1159                 spi_imx->rx = spi_imx_buf_rx_swap;
1160                 spi_imx->tx = spi_imx_buf_tx_swap;
1161                 spi_imx->dynamic_burst = 1;
1162
1163         } else {
1164                 if (spi_imx->bits_per_word <= 8) {
1165                         spi_imx->rx = spi_imx_buf_rx_u8;
1166                         spi_imx->tx = spi_imx_buf_tx_u8;
1167                 } else if (spi_imx->bits_per_word <= 16) {
1168                         spi_imx->rx = spi_imx_buf_rx_u16;
1169                         spi_imx->tx = spi_imx_buf_tx_u16;
1170                 } else {
1171                         spi_imx->rx = spi_imx_buf_rx_u32;
1172                         spi_imx->tx = spi_imx_buf_tx_u32;
1173                 }
1174                 spi_imx->dynamic_burst = 0;
1175         }
1176
1177         if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1178                 spi_imx->usedma = 1;
1179         else
1180                 spi_imx->usedma = 0;
1181
1182         if (spi_imx->usedma) {
1183                 ret = spi_imx_dma_configure(spi->master);
1184                 if (ret)
1185                         return ret;
1186         }
1187
1188         if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1189                 spi_imx->rx = mx53_ecspi_rx_slave;
1190                 spi_imx->tx = mx53_ecspi_tx_slave;
1191                 spi_imx->slave_burst = t->len;
1192         }
1193
1194         spi_imx->devtype_data->config(spi);
1195
1196         return 0;
1197 }
1198
1199 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1200 {
1201         struct spi_master *master = spi_imx->bitbang.master;
1202
1203         if (master->dma_rx) {
1204                 dma_release_channel(master->dma_rx);
1205                 master->dma_rx = NULL;
1206         }
1207
1208         if (master->dma_tx) {
1209                 dma_release_channel(master->dma_tx);
1210                 master->dma_tx = NULL;
1211         }
1212 }
1213
1214 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1215                              struct spi_master *master)
1216 {
1217         int ret;
1218
1219         /* use pio mode for i.mx6dl chip TKT238285 */
1220         if (of_machine_is_compatible("fsl,imx6dl"))
1221                 return 0;
1222
1223         spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1224
1225         /* Prepare for TX DMA: */
1226         master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
1227         if (IS_ERR(master->dma_tx)) {
1228                 ret = PTR_ERR(master->dma_tx);
1229                 dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1230                 master->dma_tx = NULL;
1231                 goto err;
1232         }
1233
1234         /* Prepare for RX : */
1235         master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
1236         if (IS_ERR(master->dma_rx)) {
1237                 ret = PTR_ERR(master->dma_rx);
1238                 dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1239                 master->dma_rx = NULL;
1240                 goto err;
1241         }
1242
1243         init_completion(&spi_imx->dma_rx_completion);
1244         init_completion(&spi_imx->dma_tx_completion);
1245         master->can_dma = spi_imx_can_dma;
1246         master->max_dma_len = MAX_SDMA_BD_BYTES;
1247         spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1248                                          SPI_MASTER_MUST_TX;
1249
1250         return 0;
1251 err:
1252         spi_imx_sdma_exit(spi_imx);
1253         return ret;
1254 }
1255
1256 static void spi_imx_dma_rx_callback(void *cookie)
1257 {
1258         struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1259
1260         complete(&spi_imx->dma_rx_completion);
1261 }
1262
1263 static void spi_imx_dma_tx_callback(void *cookie)
1264 {
1265         struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1266
1267         complete(&spi_imx->dma_tx_completion);
1268 }
1269
1270 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1271 {
1272         unsigned long timeout = 0;
1273
1274         /* Time with actual data transfer and CS change delay related to HW */
1275         timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1276
1277         /* Add extra second for scheduler related activities */
1278         timeout += 1;
1279
1280         /* Double calculated timeout */
1281         return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1282 }
1283
1284 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1285                                 struct spi_transfer *transfer)
1286 {
1287         struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1288         unsigned long transfer_timeout;
1289         unsigned long timeout;
1290         struct spi_master *master = spi_imx->bitbang.master;
1291         struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1292
1293         /*
1294          * The TX DMA setup starts the transfer, so make sure RX is configured
1295          * before TX.
1296          */
1297         desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1298                                 rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1299                                 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1300         if (!desc_rx)
1301                 return -EINVAL;
1302
1303         desc_rx->callback = spi_imx_dma_rx_callback;
1304         desc_rx->callback_param = (void *)spi_imx;
1305         dmaengine_submit(desc_rx);
1306         reinit_completion(&spi_imx->dma_rx_completion);
1307         dma_async_issue_pending(master->dma_rx);
1308
1309         desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1310                                 tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1311                                 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1312         if (!desc_tx) {
1313                 dmaengine_terminate_all(master->dma_tx);
1314                 return -EINVAL;
1315         }
1316
1317         desc_tx->callback = spi_imx_dma_tx_callback;
1318         desc_tx->callback_param = (void *)spi_imx;
1319         dmaengine_submit(desc_tx);
1320         reinit_completion(&spi_imx->dma_tx_completion);
1321         dma_async_issue_pending(master->dma_tx);
1322
1323         transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1324
1325         /* Wait SDMA to finish the data transfer.*/
1326         timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1327                                                 transfer_timeout);
1328         if (!timeout) {
1329                 dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1330                 dmaengine_terminate_all(master->dma_tx);
1331                 dmaengine_terminate_all(master->dma_rx);
1332                 return -ETIMEDOUT;
1333         }
1334
1335         timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1336                                               transfer_timeout);
1337         if (!timeout) {
1338                 dev_err(&master->dev, "I/O Error in DMA RX\n");
1339                 spi_imx->devtype_data->reset(spi_imx);
1340                 dmaengine_terminate_all(master->dma_rx);
1341                 return -ETIMEDOUT;
1342         }
1343
1344         return transfer->len;
1345 }
1346
1347 static int spi_imx_pio_transfer(struct spi_device *spi,
1348                                 struct spi_transfer *transfer)
1349 {
1350         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1351         unsigned long transfer_timeout;
1352         unsigned long timeout;
1353
1354         spi_imx->tx_buf = transfer->tx_buf;
1355         spi_imx->rx_buf = transfer->rx_buf;
1356         spi_imx->count = transfer->len;
1357         spi_imx->txfifo = 0;
1358         spi_imx->remainder = 0;
1359
1360         reinit_completion(&spi_imx->xfer_done);
1361
1362         spi_imx_push(spi_imx);
1363
1364         spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1365
1366         transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1367
1368         timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1369                                               transfer_timeout);
1370         if (!timeout) {
1371                 dev_err(&spi->dev, "I/O Error in PIO\n");
1372                 spi_imx->devtype_data->reset(spi_imx);
1373                 return -ETIMEDOUT;
1374         }
1375
1376         return transfer->len;
1377 }
1378
1379 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1380                                       struct spi_transfer *transfer)
1381 {
1382         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1383         int ret = transfer->len;
1384
1385         if (is_imx53_ecspi(spi_imx) &&
1386             transfer->len > MX53_MAX_TRANSFER_BYTES) {
1387                 dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1388                         MX53_MAX_TRANSFER_BYTES);
1389                 return -EMSGSIZE;
1390         }
1391
1392         spi_imx->tx_buf = transfer->tx_buf;
1393         spi_imx->rx_buf = transfer->rx_buf;
1394         spi_imx->count = transfer->len;
1395         spi_imx->txfifo = 0;
1396         spi_imx->remainder = 0;
1397
1398         reinit_completion(&spi_imx->xfer_done);
1399         spi_imx->slave_aborted = false;
1400
1401         spi_imx_push(spi_imx);
1402
1403         spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1404
1405         if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1406             spi_imx->slave_aborted) {
1407                 dev_dbg(&spi->dev, "interrupted\n");
1408                 ret = -EINTR;
1409         }
1410
1411         /* ecspi has a HW issue when works in Slave mode,
1412          * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1413          * ECSPI_TXDATA keeps shift out the last word data,
1414          * so we have to disable ECSPI when in slave mode after the
1415          * transfer completes
1416          */
1417         if (spi_imx->devtype_data->disable)
1418                 spi_imx->devtype_data->disable(spi_imx);
1419
1420         return ret;
1421 }
1422
1423 static int spi_imx_transfer(struct spi_device *spi,
1424                                 struct spi_transfer *transfer)
1425 {
1426         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1427
1428         /* flush rxfifo before transfer */
1429         while (spi_imx->devtype_data->rx_available(spi_imx))
1430                 readl(spi_imx->base + MXC_CSPIRXDATA);
1431
1432         if (spi_imx->slave_mode)
1433                 return spi_imx_pio_transfer_slave(spi, transfer);
1434
1435         if (spi_imx->usedma)
1436                 return spi_imx_dma_transfer(spi_imx, transfer);
1437         else
1438                 return spi_imx_pio_transfer(spi, transfer);
1439 }
1440
1441 static int spi_imx_setup(struct spi_device *spi)
1442 {
1443         dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1444                  spi->mode, spi->bits_per_word, spi->max_speed_hz);
1445
1446         if (spi->mode & SPI_NO_CS)
1447                 return 0;
1448
1449         if (gpio_is_valid(spi->cs_gpio))
1450                 gpio_direction_output(spi->cs_gpio,
1451                                       spi->mode & SPI_CS_HIGH ? 0 : 1);
1452
1453         spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1454
1455         return 0;
1456 }
1457
1458 static void spi_imx_cleanup(struct spi_device *spi)
1459 {
1460 }
1461
1462 static int
1463 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1464 {
1465         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1466         int ret;
1467
1468         ret = clk_enable(spi_imx->clk_per);
1469         if (ret)
1470                 return ret;
1471
1472         ret = clk_enable(spi_imx->clk_ipg);
1473         if (ret) {
1474                 clk_disable(spi_imx->clk_per);
1475                 return ret;
1476         }
1477
1478         return 0;
1479 }
1480
1481 static int
1482 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1483 {
1484         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1485
1486         clk_disable(spi_imx->clk_ipg);
1487         clk_disable(spi_imx->clk_per);
1488         return 0;
1489 }
1490
1491 static int spi_imx_slave_abort(struct spi_master *master)
1492 {
1493         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1494
1495         spi_imx->slave_aborted = true;
1496         complete(&spi_imx->xfer_done);
1497
1498         return 0;
1499 }
1500
1501 static int spi_imx_probe(struct platform_device *pdev)
1502 {
1503         struct device_node *np = pdev->dev.of_node;
1504         const struct of_device_id *of_id =
1505                         of_match_device(spi_imx_dt_ids, &pdev->dev);
1506         struct spi_imx_master *mxc_platform_info =
1507                         dev_get_platdata(&pdev->dev);
1508         struct spi_master *master;
1509         struct spi_imx_data *spi_imx;
1510         struct resource *res;
1511         int i, ret, irq, spi_drctl;
1512         const struct spi_imx_devtype_data *devtype_data = of_id ? of_id->data :
1513                 (struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1514         bool slave_mode;
1515
1516         if (!np && !mxc_platform_info) {
1517                 dev_err(&pdev->dev, "can't get the platform data\n");
1518                 return -EINVAL;
1519         }
1520
1521         slave_mode = devtype_data->has_slavemode &&
1522                         of_property_read_bool(np, "spi-slave");
1523         if (slave_mode)
1524                 master = spi_alloc_slave(&pdev->dev,
1525                                          sizeof(struct spi_imx_data));
1526         else
1527                 master = spi_alloc_master(&pdev->dev,
1528                                           sizeof(struct spi_imx_data));
1529         if (!master)
1530                 return -ENOMEM;
1531
1532         ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1533         if ((ret < 0) || (spi_drctl >= 0x3)) {
1534                 /* '11' is reserved */
1535                 spi_drctl = 0;
1536         }
1537
1538         platform_set_drvdata(pdev, master);
1539
1540         master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1541         master->bus_num = np ? -1 : pdev->id;
1542
1543         spi_imx = spi_master_get_devdata(master);
1544         spi_imx->bitbang.master = master;
1545         spi_imx->dev = &pdev->dev;
1546         spi_imx->slave_mode = slave_mode;
1547
1548         spi_imx->devtype_data = devtype_data;
1549
1550         /* Get number of chip selects, either platform data or OF */
1551         if (mxc_platform_info) {
1552                 master->num_chipselect = mxc_platform_info->num_chipselect;
1553                 if (mxc_platform_info->chipselect) {
1554                         master->cs_gpios = devm_kcalloc(&master->dev,
1555                                 master->num_chipselect, sizeof(int),
1556                                 GFP_KERNEL);
1557                         if (!master->cs_gpios)
1558                                 return -ENOMEM;
1559
1560                         for (i = 0; i < master->num_chipselect; i++)
1561                                 master->cs_gpios[i] = mxc_platform_info->chipselect[i];
1562                 }
1563         } else {
1564                 u32 num_cs;
1565
1566                 if (!of_property_read_u32(np, "num-cs", &num_cs))
1567                         master->num_chipselect = num_cs;
1568                 /* If not preset, default value of 1 is used */
1569         }
1570
1571         spi_imx->bitbang.chipselect = spi_imx_chipselect;
1572         spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1573         spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1574         spi_imx->bitbang.master->setup = spi_imx_setup;
1575         spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1576         spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1577         spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1578         spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1579         spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1580                                              | SPI_NO_CS;
1581         if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1582             is_imx53_ecspi(spi_imx))
1583                 spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1584
1585         spi_imx->spi_drctl = spi_drctl;
1586
1587         init_completion(&spi_imx->xfer_done);
1588
1589         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1590         spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1591         if (IS_ERR(spi_imx->base)) {
1592                 ret = PTR_ERR(spi_imx->base);
1593                 goto out_master_put;
1594         }
1595         spi_imx->base_phys = res->start;
1596
1597         irq = platform_get_irq(pdev, 0);
1598         if (irq < 0) {
1599                 ret = irq;
1600                 goto out_master_put;
1601         }
1602
1603         ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1604                                dev_name(&pdev->dev), spi_imx);
1605         if (ret) {
1606                 dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1607                 goto out_master_put;
1608         }
1609
1610         spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1611         if (IS_ERR(spi_imx->clk_ipg)) {
1612                 ret = PTR_ERR(spi_imx->clk_ipg);
1613                 goto out_master_put;
1614         }
1615
1616         spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1617         if (IS_ERR(spi_imx->clk_per)) {
1618                 ret = PTR_ERR(spi_imx->clk_per);
1619                 goto out_master_put;
1620         }
1621
1622         ret = clk_prepare_enable(spi_imx->clk_per);
1623         if (ret)
1624                 goto out_master_put;
1625
1626         ret = clk_prepare_enable(spi_imx->clk_ipg);
1627         if (ret)
1628                 goto out_put_per;
1629
1630         spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1631         /*
1632          * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1633          * if validated on other chips.
1634          */
1635         if (spi_imx->devtype_data->has_dmamode) {
1636                 ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1637                 if (ret == -EPROBE_DEFER)
1638                         goto out_clk_put;
1639
1640                 if (ret < 0)
1641                         dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1642                                 ret);
1643         }
1644
1645         spi_imx->devtype_data->reset(spi_imx);
1646
1647         spi_imx->devtype_data->intctrl(spi_imx, 0);
1648
1649         master->dev.of_node = pdev->dev.of_node;
1650         ret = spi_bitbang_start(&spi_imx->bitbang);
1651         if (ret) {
1652                 dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1653                 goto out_clk_put;
1654         }
1655
1656         /* Request GPIO CS lines, if any */
1657         if (!spi_imx->slave_mode && master->cs_gpios) {
1658                 for (i = 0; i < master->num_chipselect; i++) {
1659                         if (!gpio_is_valid(master->cs_gpios[i]))
1660                                 continue;
1661
1662                         ret = devm_gpio_request(&pdev->dev,
1663                                                 master->cs_gpios[i],
1664                                                 DRIVER_NAME);
1665                         if (ret) {
1666                                 dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
1667                                         master->cs_gpios[i]);
1668                                 goto out_spi_bitbang;
1669                         }
1670                 }
1671         }
1672
1673         dev_info(&pdev->dev, "probed\n");
1674
1675         clk_disable(spi_imx->clk_ipg);
1676         clk_disable(spi_imx->clk_per);
1677         return ret;
1678
1679 out_spi_bitbang:
1680         spi_bitbang_stop(&spi_imx->bitbang);
1681 out_clk_put:
1682         clk_disable_unprepare(spi_imx->clk_ipg);
1683 out_put_per:
1684         clk_disable_unprepare(spi_imx->clk_per);
1685 out_master_put:
1686         spi_master_put(master);
1687
1688         return ret;
1689 }
1690
1691 static int spi_imx_remove(struct platform_device *pdev)
1692 {
1693         struct spi_master *master = platform_get_drvdata(pdev);
1694         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1695         int ret;
1696
1697         spi_bitbang_stop(&spi_imx->bitbang);
1698
1699         ret = clk_enable(spi_imx->clk_per);
1700         if (ret)
1701                 return ret;
1702
1703         ret = clk_enable(spi_imx->clk_ipg);
1704         if (ret) {
1705                 clk_disable(spi_imx->clk_per);
1706                 return ret;
1707         }
1708
1709         writel(0, spi_imx->base + MXC_CSPICTRL);
1710         clk_disable_unprepare(spi_imx->clk_ipg);
1711         clk_disable_unprepare(spi_imx->clk_per);
1712         spi_imx_sdma_exit(spi_imx);
1713         spi_master_put(master);
1714
1715         return 0;
1716 }
1717
1718 static struct platform_driver spi_imx_driver = {
1719         .driver = {
1720                    .name = DRIVER_NAME,
1721                    .of_match_table = spi_imx_dt_ids,
1722                    },
1723         .id_table = spi_imx_devtype,
1724         .probe = spi_imx_probe,
1725         .remove = spi_imx_remove,
1726 };
1727 module_platform_driver(spi_imx_driver);
1728
1729 MODULE_DESCRIPTION("SPI Controller driver");
1730 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1731 MODULE_LICENSE("GPL");
1732 MODULE_ALIAS("platform:" DRIVER_NAME);