drivers/spi/spi-imx.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
is_imx27_cspi
is_imx35_cspi
is_imx51_ecspi
is_imx53_ecspi
spi_imx_clkdiv_1
spi_imx_clkdiv_2
spi_imx_bytes_per_word
spi_imx_can_dma
spi_imx_buf_rx_swap_u32
spi_imx_buf_rx_swap
spi_imx_buf_tx_swap_u32
spi_imx_buf_tx_swap
mx53_ecspi_rx_slave
mx53_ecspi_tx_slave
mx51_ecspi_clkdiv
mx51_ecspi_intctrl
mx51_ecspi_trigger
mx51_ecspi_disable
mx51_ecspi_prepare_message
mx51_ecspi_prepare_transfer
mx51_setup_wml
mx51_ecspi_rx_available
mx51_ecspi_reset
mx31_intctrl
mx31_trigger
mx31_prepare_message
mx31_prepare_transfer
mx31_rx_available
mx31_reset
mx21_intctrl
mx21_trigger
mx21_prepare_message
mx21_prepare_transfer
mx21_rx_available
mx21_reset
mx1_intctrl
mx1_trigger
mx1_prepare_message
mx1_prepare_transfer
mx1_rx_available
mx1_reset
spi_imx_chipselect
spi_imx_set_burst_len
spi_imx_push
spi_imx_isr
spi_imx_dma_configure
spi_imx_setupxfer
spi_imx_sdma_exit
spi_imx_sdma_init
spi_imx_dma_rx_callback
spi_imx_dma_tx_callback
spi_imx_calculate_timeout
spi_imx_dma_transfer
spi_imx_pio_transfer
spi_imx_pio_transfer_slave
spi_imx_transfer
spi_imx_setup
spi_imx_cleanup
spi_imx_prepare_message
spi_imx_unprepare_message
spi_imx_slave_abort
spi_imx_probe
spi_imx_remove
   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 static bool use_dma = true;
  32 module_param(use_dma, bool, 0644);
  33 MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
  34 
  35 #define MXC_CSPIRXDATA          0x00
  36 #define MXC_CSPITXDATA          0x04
  37 #define MXC_CSPICTRL            0x08
  38 #define MXC_CSPIINT             0x0c
  39 #define MXC_RESET               0x1c
  40 
  41 /* generic defines to abstract from the different register layouts */
  42 #define MXC_INT_RR      (1 << 0) /* Receive data ready interrupt */
  43 #define MXC_INT_TE      (1 << 1) /* Transmit FIFO empty interrupt */
  44 #define MXC_INT_RDR     BIT(4) /* Receive date threshold interrupt */
  45 
  46 /* The maximum bytes that a sdma BD can transfer. */
  47 #define MAX_SDMA_BD_BYTES (1 << 15)
  48 #define MX51_ECSPI_CTRL_MAX_BURST       512
  49 /* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
  50 #define MX53_MAX_TRANSFER_BYTES         512
  51 
  52 enum spi_imx_devtype {
  53         IMX1_CSPI,
  54         IMX21_CSPI,
  55         IMX27_CSPI,
  56         IMX31_CSPI,
  57         IMX35_CSPI,     /* CSPI on all i.mx except above */
  58         IMX51_ECSPI,    /* ECSPI on i.mx51 */
  59         IMX53_ECSPI,    /* ECSPI on i.mx53 and later */
  60 };
  61 
  62 struct spi_imx_data;
  63 
  64 struct spi_imx_devtype_data {
  65         void (*intctrl)(struct spi_imx_data *, int);
  66         int (*prepare_message)(struct spi_imx_data *, struct spi_message *);
  67         int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *,
  68                                 struct spi_transfer *);
  69         void (*trigger)(struct spi_imx_data *);
  70         int (*rx_available)(struct spi_imx_data *);
  71         void (*reset)(struct spi_imx_data *);
  72         void (*setup_wml)(struct spi_imx_data *);
  73         void (*disable)(struct spi_imx_data *);
  74         bool has_dmamode;
  75         bool has_slavemode;
  76         unsigned int fifo_size;
  77         bool dynamic_burst;
  78         enum spi_imx_devtype devtype;
  79 };
  80 
  81 struct spi_imx_data {
  82         struct spi_bitbang bitbang;
  83         struct device *dev;
  84 
  85         struct completion xfer_done;
  86         void __iomem *base;
  87         unsigned long base_phys;
  88 
  89         struct clk *clk_per;
  90         struct clk *clk_ipg;
  91         unsigned long spi_clk;
  92         unsigned int spi_bus_clk;
  93 
  94         unsigned int bits_per_word;
  95         unsigned int spi_drctl;
  96 
  97         unsigned int count, remainder;
  98         void (*tx)(struct spi_imx_data *);
  99         void (*rx)(struct spi_imx_data *);
 100         void *rx_buf;
 101         const void *tx_buf;
 102         unsigned int txfifo; /* number of words pushed in tx FIFO */
 103         unsigned int dynamic_burst;
 104 
 105         /* Slave mode */
 106         bool slave_mode;
 107         bool slave_aborted;
 108         unsigned int slave_burst;
 109 
 110         /* DMA */
 111         bool usedma;
 112         u32 wml;
 113         struct completion dma_rx_completion;
 114         struct completion dma_tx_completion;
 115 
 116         const struct spi_imx_devtype_data *devtype_data;
 117 };
 118 
 119 static inline int is_imx27_cspi(struct spi_imx_data *d)
 120 {
 121         return d->devtype_data->devtype == IMX27_CSPI;
 122 }
 123 
 124 static inline int is_imx35_cspi(struct spi_imx_data *d)
 125 {
 126         return d->devtype_data->devtype == IMX35_CSPI;
 127 }
 128 
 129 static inline int is_imx51_ecspi(struct spi_imx_data *d)
 130 {
 131         return d->devtype_data->devtype == IMX51_ECSPI;
 132 }
 133 
 134 static inline int is_imx53_ecspi(struct spi_imx_data *d)
 135 {
 136         return d->devtype_data->devtype == IMX53_ECSPI;
 137 }
 138 
 139 #define MXC_SPI_BUF_RX(type)                                            \
 140 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)         \
 141 {                                                                       \
 142         unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);       \
 143                                                                         \
 144         if (spi_imx->rx_buf) {                                          \
 145                 *(type *)spi_imx->rx_buf = val;                         \
 146                 spi_imx->rx_buf += sizeof(type);                        \
 147         }                                                               \
 148                                                                         \
 149         spi_imx->remainder -= sizeof(type);                             \
 150 }
 151 
 152 #define MXC_SPI_BUF_TX(type)                                            \
 153 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)         \
 154 {                                                                       \
 155         type val = 0;                                                   \
 156                                                                         \
 157         if (spi_imx->tx_buf) {                                          \
 158                 val = *(type *)spi_imx->tx_buf;                         \
 159                 spi_imx->tx_buf += sizeof(type);                        \
 160         }                                                               \
 161                                                                         \
 162         spi_imx->count -= sizeof(type);                                 \
 163                                                                         \
 164         writel(val, spi_imx->base + MXC_CSPITXDATA);                    \
 165 }
 166 
 167 MXC_SPI_BUF_RX(u8)
 168 MXC_SPI_BUF_TX(u8)
 169 MXC_SPI_BUF_RX(u16)
 170 MXC_SPI_BUF_TX(u16)
 171 MXC_SPI_BUF_RX(u32)
 172 MXC_SPI_BUF_TX(u32)
 173 
 174 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 175  * (which is currently not the case in this driver)
 176  */
 177 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 178         256, 384, 512, 768, 1024};
 179 
 180 /* MX21, MX27 */
 181 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 182                 unsigned int fspi, unsigned int max, unsigned int *fres)
 183 {
 184         int i;
 185 
 186         for (i = 2; i < max; i++)
 187                 if (fspi * mxc_clkdivs[i] >= fin)
 188                         break;
 189 
 190         *fres = fin / mxc_clkdivs[i];
 191         return i;
 192 }
 193 
 194 /* MX1, MX31, MX35, MX51 CSPI */
 195 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 196                 unsigned int fspi, unsigned int *fres)
 197 {
 198         int i, div = 4;
 199 
 200         for (i = 0; i < 7; i++) {
 201                 if (fspi * div >= fin)
 202                         goto out;
 203                 div <<= 1;
 204         }
 205 
 206 out:
 207         *fres = fin / div;
 208         return i;
 209 }
 210 
 211 static int spi_imx_bytes_per_word(const int bits_per_word)
 212 {
 213         if (bits_per_word <= 8)
 214                 return 1;
 215         else if (bits_per_word <= 16)
 216                 return 2;
 217         else
 218                 return 4;
 219 }
 220 
 221 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 222                          struct spi_transfer *transfer)
 223 {
 224         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 225 
 226         if (!use_dma)
 227                 return false;
 228 
 229         if (!master->dma_rx)
 230                 return false;
 231 
 232         if (spi_imx->slave_mode)
 233                 return false;
 234 
 235         if (transfer->len < spi_imx->devtype_data->fifo_size)
 236                 return false;
 237 
 238         spi_imx->dynamic_burst = 0;
 239 
 240         return true;
 241 }
 242 
 243 #define MX51_ECSPI_CTRL         0x08
 244 #define MX51_ECSPI_CTRL_ENABLE          (1 <<  0)
 245 #define MX51_ECSPI_CTRL_XCH             (1 <<  2)
 246 #define MX51_ECSPI_CTRL_SMC             (1 << 3)
 247 #define MX51_ECSPI_CTRL_MODE_MASK       (0xf << 4)
 248 #define MX51_ECSPI_CTRL_DRCTL(drctl)    ((drctl) << 16)
 249 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET  8
 250 #define MX51_ECSPI_CTRL_PREDIV_OFFSET   12
 251 #define MX51_ECSPI_CTRL_CS(cs)          ((cs) << 18)
 252 #define MX51_ECSPI_CTRL_BL_OFFSET       20
 253 #define MX51_ECSPI_CTRL_BL_MASK         (0xfff << 20)
 254 
 255 #define MX51_ECSPI_CONFIG       0x0c
 256 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)   (1 << ((cs) +  0))
 257 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)   (1 << ((cs) +  4))
 258 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)   (1 << ((cs) +  8))
 259 #define MX51_ECSPI_CONFIG_SSBPOL(cs)    (1 << ((cs) + 12))
 260 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)   (1 << ((cs) + 20))
 261 
 262 #define MX51_ECSPI_INT          0x10
 263 #define MX51_ECSPI_INT_TEEN             (1 <<  0)
 264 #define MX51_ECSPI_INT_RREN             (1 <<  3)
 265 #define MX51_ECSPI_INT_RDREN            (1 <<  4)
 266 
 267 #define MX51_ECSPI_DMA          0x14
 268 #define MX51_ECSPI_DMA_TX_WML(wml)      ((wml) & 0x3f)
 269 #define MX51_ECSPI_DMA_RX_WML(wml)      (((wml) & 0x3f) << 16)
 270 #define MX51_ECSPI_DMA_RXT_WML(wml)     (((wml) & 0x3f) << 24)
 271 
 272 #define MX51_ECSPI_DMA_TEDEN            (1 << 7)
 273 #define MX51_ECSPI_DMA_RXDEN            (1 << 23)
 274 #define MX51_ECSPI_DMA_RXTDEN           (1 << 31)
 275 
 276 #define MX51_ECSPI_STAT         0x18
 277 #define MX51_ECSPI_STAT_RR              (1 <<  3)
 278 
 279 #define MX51_ECSPI_TESTREG      0x20
 280 #define MX51_ECSPI_TESTREG_LBC  BIT(31)
 281 
 282 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
 283 {
 284         unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
 285 #ifdef __LITTLE_ENDIAN
 286         unsigned int bytes_per_word;
 287 #endif
 288 
 289         if (spi_imx->rx_buf) {
 290 #ifdef __LITTLE_ENDIAN
 291                 bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 292                 if (bytes_per_word == 1)
 293                         val = cpu_to_be32(val);
 294                 else if (bytes_per_word == 2)
 295                         val = (val << 16) | (val >> 16);
 296 #endif
 297                 *(u32 *)spi_imx->rx_buf = val;
 298                 spi_imx->rx_buf += sizeof(u32);
 299         }
 300 
 301         spi_imx->remainder -= sizeof(u32);
 302 }
 303 
 304 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
 305 {
 306         int unaligned;
 307         u32 val;
 308 
 309         unaligned = spi_imx->remainder % 4;
 310 
 311         if (!unaligned) {
 312                 spi_imx_buf_rx_swap_u32(spi_imx);
 313                 return;
 314         }
 315 
 316         if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 317                 spi_imx_buf_rx_u16(spi_imx);
 318                 return;
 319         }
 320 
 321         val = readl(spi_imx->base + MXC_CSPIRXDATA);
 322 
 323         while (unaligned--) {
 324                 if (spi_imx->rx_buf) {
 325                         *(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
 326                         spi_imx->rx_buf++;
 327                 }
 328                 spi_imx->remainder--;
 329         }
 330 }
 331 
 332 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
 333 {
 334         u32 val = 0;
 335 #ifdef __LITTLE_ENDIAN
 336         unsigned int bytes_per_word;
 337 #endif
 338 
 339         if (spi_imx->tx_buf) {
 340                 val = *(u32 *)spi_imx->tx_buf;
 341                 spi_imx->tx_buf += sizeof(u32);
 342         }
 343 
 344         spi_imx->count -= sizeof(u32);
 345 #ifdef __LITTLE_ENDIAN
 346         bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
 347 
 348         if (bytes_per_word == 1)
 349                 val = cpu_to_be32(val);
 350         else if (bytes_per_word == 2)
 351                 val = (val << 16) | (val >> 16);
 352 #endif
 353         writel(val, spi_imx->base + MXC_CSPITXDATA);
 354 }
 355 
 356 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
 357 {
 358         int unaligned;
 359         u32 val = 0;
 360 
 361         unaligned = spi_imx->count % 4;
 362 
 363         if (!unaligned) {
 364                 spi_imx_buf_tx_swap_u32(spi_imx);
 365                 return;
 366         }
 367 
 368         if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
 369                 spi_imx_buf_tx_u16(spi_imx);
 370                 return;
 371         }
 372 
 373         while (unaligned--) {
 374                 if (spi_imx->tx_buf) {
 375                         val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
 376                         spi_imx->tx_buf++;
 377                 }
 378                 spi_imx->count--;
 379         }
 380 
 381         writel(val, spi_imx->base + MXC_CSPITXDATA);
 382 }
 383 
 384 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
 385 {
 386         u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
 387 
 388         if (spi_imx->rx_buf) {
 389                 int n_bytes = spi_imx->slave_burst % sizeof(val);
 390 
 391                 if (!n_bytes)
 392                         n_bytes = sizeof(val);
 393 
 394                 memcpy(spi_imx->rx_buf,
 395                        ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
 396 
 397                 spi_imx->rx_buf += n_bytes;
 398                 spi_imx->slave_burst -= n_bytes;
 399         }
 400 
 401         spi_imx->remainder -= sizeof(u32);
 402 }
 403 
 404 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
 405 {
 406         u32 val = 0;
 407         int n_bytes = spi_imx->count % sizeof(val);
 408 
 409         if (!n_bytes)
 410                 n_bytes = sizeof(val);
 411 
 412         if (spi_imx->tx_buf) {
 413                 memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
 414                        spi_imx->tx_buf, n_bytes);
 415                 val = cpu_to_be32(val);
 416                 spi_imx->tx_buf += n_bytes;
 417         }
 418 
 419         spi_imx->count -= n_bytes;
 420 
 421         writel(val, spi_imx->base + MXC_CSPITXDATA);
 422 }
 423 
 424 /* MX51 eCSPI */
 425 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 426                                       unsigned int fspi, unsigned int *fres)
 427 {
 428         /*
 429          * there are two 4-bit dividers, the pre-divider divides by
 430          * $pre, the post-divider by 2^$post
 431          */
 432         unsigned int pre, post;
 433         unsigned int fin = spi_imx->spi_clk;
 434 
 435         if (unlikely(fspi > fin))
 436                 return 0;
 437 
 438         post = fls(fin) - fls(fspi);
 439         if (fin > fspi << post)
 440                 post++;
 441 
 442         /* now we have: (fin <= fspi << post) with post being minimal */
 443 
 444         post = max(4U, post) - 4;
 445         if (unlikely(post > 0xf)) {
 446                 dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
 447                                 fspi, fin);
 448                 return 0xff;
 449         }
 450 
 451         pre = DIV_ROUND_UP(fin, fspi << post) - 1;
 452 
 453         dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
 454                         __func__, fin, fspi, post, pre);
 455 
 456         /* Resulting frequency for the SCLK line. */
 457         *fres = (fin / (pre + 1)) >> post;
 458 
 459         return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
 460                 (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
 461 }
 462 
 463 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 464 {
 465         unsigned val = 0;
 466 
 467         if (enable & MXC_INT_TE)
 468                 val |= MX51_ECSPI_INT_TEEN;
 469 
 470         if (enable & MXC_INT_RR)
 471                 val |= MX51_ECSPI_INT_RREN;
 472 
 473         if (enable & MXC_INT_RDR)
 474                 val |= MX51_ECSPI_INT_RDREN;
 475 
 476         writel(val, spi_imx->base + MX51_ECSPI_INT);
 477 }
 478 
 479 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 480 {
 481         u32 reg;
 482 
 483         reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
 484         reg |= MX51_ECSPI_CTRL_XCH;
 485         writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 486 }
 487 
 488 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
 489 {
 490         u32 ctrl;
 491 
 492         ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 493         ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
 494         writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 495 }
 496 
 497 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
 498                                       struct spi_message *msg)
 499 {
 500         struct spi_device *spi = msg->spi;
 501         u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
 502         u32 testreg;
 503         u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 504 
 505         /* set Master or Slave mode */
 506         if (spi_imx->slave_mode)
 507                 ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
 508         else
 509                 ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 510 
 511         /*
 512          * Enable SPI_RDY handling (falling edge/level triggered).
 513          */
 514         if (spi->mode & SPI_READY)
 515                 ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
 516 
 517         /* set chip select to use */
 518         ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
 519 
 520         /*
 521          * The ctrl register must be written first, with the EN bit set other
 522          * registers must not be written to.
 523          */
 524         writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 525 
 526         testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
 527         if (spi->mode & SPI_LOOP)
 528                 testreg |= MX51_ECSPI_TESTREG_LBC;
 529         else
 530                 testreg &= ~MX51_ECSPI_TESTREG_LBC;
 531         writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
 532 
 533         /*
 534          * eCSPI burst completion by Chip Select signal in Slave mode
 535          * is not functional for imx53 Soc, config SPI burst completed when
 536          * BURST_LENGTH + 1 bits are received
 537          */
 538         if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 539                 cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 540         else
 541                 cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 542 
 543         if (spi->mode & SPI_CPHA)
 544                 cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 545         else
 546                 cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
 547 
 548         if (spi->mode & SPI_CPOL) {
 549                 cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 550                 cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 551         } else {
 552                 cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
 553                 cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
 554         }
 555 
 556         if (spi->mode & SPI_CS_HIGH)
 557                 cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 558         else
 559                 cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
 560 
 561         writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
 562 
 563         return 0;
 564 }
 565 
 566 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
 567                                        struct spi_device *spi,
 568                                        struct spi_transfer *t)
 569 {
 570         u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
 571         u32 clk = t->speed_hz, delay;
 572 
 573         /* Clear BL field and set the right value */
 574         ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
 575         if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
 576                 ctrl |= (spi_imx->slave_burst * 8 - 1)
 577                         << MX51_ECSPI_CTRL_BL_OFFSET;
 578         else
 579                 ctrl |= (spi_imx->bits_per_word - 1)
 580                         << MX51_ECSPI_CTRL_BL_OFFSET;
 581 
 582         /* set clock speed */
 583         ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
 584                   0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
 585         ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk);
 586         spi_imx->spi_bus_clk = clk;
 587 
 588         if (spi_imx->usedma)
 589                 ctrl |= MX51_ECSPI_CTRL_SMC;
 590 
 591         writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
 592 
 593         /*
 594          * Wait until the changes in the configuration register CONFIGREG
 595          * propagate into the hardware. It takes exactly one tick of the
 596          * SCLK clock, but we will wait two SCLK clock just to be sure. The
 597          * effect of the delay it takes for the hardware to apply changes
 598          * is noticable if the SCLK clock run very slow. In such a case, if
 599          * the polarity of SCLK should be inverted, the GPIO ChipSelect might
 600          * be asserted before the SCLK polarity changes, which would disrupt
 601          * the SPI communication as the device on the other end would consider
 602          * the change of SCLK polarity as a clock tick already.
 603          */
 604         delay = (2 * 1000000) / clk;
 605         if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
 606                 udelay(delay);
 607         else                    /* SCLK is _very_ slow */
 608                 usleep_range(delay, delay + 10);
 609 
 610         return 0;
 611 }
 612 
 613 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
 614 {
 615         /*
 616          * Configure the DMA register: setup the watermark
 617          * and enable DMA request.
 618          */
 619         writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
 620                 MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
 621                 MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
 622                 MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
 623                 MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
 624 }
 625 
 626 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
 627 {
 628         return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
 629 }
 630 
 631 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 632 {
 633         /* drain receive buffer */
 634         while (mx51_ecspi_rx_available(spi_imx))
 635                 readl(spi_imx->base + MXC_CSPIRXDATA);
 636 }
 637 
 638 #define MX31_INTREG_TEEN        (1 << 0)
 639 #define MX31_INTREG_RREN        (1 << 3)
 640 
 641 #define MX31_CSPICTRL_ENABLE    (1 << 0)
 642 #define MX31_CSPICTRL_MASTER    (1 << 1)
 643 #define MX31_CSPICTRL_XCH       (1 << 2)
 644 #define MX31_CSPICTRL_SMC       (1 << 3)
 645 #define MX31_CSPICTRL_POL       (1 << 4)
 646 #define MX31_CSPICTRL_PHA       (1 << 5)
 647 #define MX31_CSPICTRL_SSCTL     (1 << 6)
 648 #define MX31_CSPICTRL_SSPOL     (1 << 7)
 649 #define MX31_CSPICTRL_BC_SHIFT  8
 650 #define MX35_CSPICTRL_BL_SHIFT  20
 651 #define MX31_CSPICTRL_CS_SHIFT  24
 652 #define MX35_CSPICTRL_CS_SHIFT  12
 653 #define MX31_CSPICTRL_DR_SHIFT  16
 654 
 655 #define MX31_CSPI_DMAREG        0x10
 656 #define MX31_DMAREG_RH_DEN      (1<<4)
 657 #define MX31_DMAREG_TH_DEN      (1<<1)
 658 
 659 #define MX31_CSPISTATUS         0x14
 660 #define MX31_STATUS_RR          (1 << 3)
 661 
 662 #define MX31_CSPI_TESTREG       0x1C
 663 #define MX31_TEST_LBC           (1 << 14)
 664 
 665 /* These functions also work for the i.MX35, but be aware that
 666  * the i.MX35 has a slightly different register layout for bits
 667  * we do not use here.
 668  */
 669 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 670 {
 671         unsigned int val = 0;
 672 
 673         if (enable & MXC_INT_TE)
 674                 val |= MX31_INTREG_TEEN;
 675         if (enable & MXC_INT_RR)
 676                 val |= MX31_INTREG_RREN;
 677 
 678         writel(val, spi_imx->base + MXC_CSPIINT);
 679 }
 680 
 681 static void mx31_trigger(struct spi_imx_data *spi_imx)
 682 {
 683         unsigned int reg;
 684 
 685         reg = readl(spi_imx->base + MXC_CSPICTRL);
 686         reg |= MX31_CSPICTRL_XCH;
 687         writel(reg, spi_imx->base + MXC_CSPICTRL);
 688 }
 689 
 690 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
 691                                 struct spi_message *msg)
 692 {
 693         return 0;
 694 }
 695 
 696 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
 697                                  struct spi_device *spi,
 698                                  struct spi_transfer *t)
 699 {
 700         unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 701         unsigned int clk;
 702 
 703         reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
 704                 MX31_CSPICTRL_DR_SHIFT;
 705         spi_imx->spi_bus_clk = clk;
 706 
 707         if (is_imx35_cspi(spi_imx)) {
 708                 reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
 709                 reg |= MX31_CSPICTRL_SSCTL;
 710         } else {
 711                 reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
 712         }
 713 
 714         if (spi->mode & SPI_CPHA)
 715                 reg |= MX31_CSPICTRL_PHA;
 716         if (spi->mode & SPI_CPOL)
 717                 reg |= MX31_CSPICTRL_POL;
 718         if (spi->mode & SPI_CS_HIGH)
 719                 reg |= MX31_CSPICTRL_SSPOL;
 720         if (!gpio_is_valid(spi->cs_gpio))
 721                 reg |= (spi->chip_select) <<
 722                         (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 723                                                   MX31_CSPICTRL_CS_SHIFT);
 724 
 725         if (spi_imx->usedma)
 726                 reg |= MX31_CSPICTRL_SMC;
 727 
 728         writel(reg, spi_imx->base + MXC_CSPICTRL);
 729 
 730         reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
 731         if (spi->mode & SPI_LOOP)
 732                 reg |= MX31_TEST_LBC;
 733         else
 734                 reg &= ~MX31_TEST_LBC;
 735         writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
 736 
 737         if (spi_imx->usedma) {
 738                 /*
 739                  * configure DMA requests when RXFIFO is half full and
 740                  * when TXFIFO is half empty
 741                  */
 742                 writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
 743                         spi_imx->base + MX31_CSPI_DMAREG);
 744         }
 745 
 746         return 0;
 747 }
 748 
 749 static int mx31_rx_available(struct spi_imx_data *spi_imx)
 750 {
 751         return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 752 }
 753 
 754 static void mx31_reset(struct spi_imx_data *spi_imx)
 755 {
 756         /* drain receive buffer */
 757         while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
 758                 readl(spi_imx->base + MXC_CSPIRXDATA);
 759 }
 760 
 761 #define MX21_INTREG_RR          (1 << 4)
 762 #define MX21_INTREG_TEEN        (1 << 9)
 763 #define MX21_INTREG_RREN        (1 << 13)
 764 
 765 #define MX21_CSPICTRL_POL       (1 << 5)
 766 #define MX21_CSPICTRL_PHA       (1 << 6)
 767 #define MX21_CSPICTRL_SSPOL     (1 << 8)
 768 #define MX21_CSPICTRL_XCH       (1 << 9)
 769 #define MX21_CSPICTRL_ENABLE    (1 << 10)
 770 #define MX21_CSPICTRL_MASTER    (1 << 11)
 771 #define MX21_CSPICTRL_DR_SHIFT  14
 772 #define MX21_CSPICTRL_CS_SHIFT  19
 773 
 774 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
 775 {
 776         unsigned int val = 0;
 777 
 778         if (enable & MXC_INT_TE)
 779                 val |= MX21_INTREG_TEEN;
 780         if (enable & MXC_INT_RR)
 781                 val |= MX21_INTREG_RREN;
 782 
 783         writel(val, spi_imx->base + MXC_CSPIINT);
 784 }
 785 
 786 static void mx21_trigger(struct spi_imx_data *spi_imx)
 787 {
 788         unsigned int reg;
 789 
 790         reg = readl(spi_imx->base + MXC_CSPICTRL);
 791         reg |= MX21_CSPICTRL_XCH;
 792         writel(reg, spi_imx->base + MXC_CSPICTRL);
 793 }
 794 
 795 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
 796                                 struct spi_message *msg)
 797 {
 798         return 0;
 799 }
 800 
 801 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
 802                                  struct spi_device *spi,
 803                                  struct spi_transfer *t)
 804 {
 805         unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
 806         unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
 807         unsigned int clk;
 808 
 809         reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, t->speed_hz, max, &clk)
 810                 << MX21_CSPICTRL_DR_SHIFT;
 811         spi_imx->spi_bus_clk = clk;
 812 
 813         reg |= spi_imx->bits_per_word - 1;
 814 
 815         if (spi->mode & SPI_CPHA)
 816                 reg |= MX21_CSPICTRL_PHA;
 817         if (spi->mode & SPI_CPOL)
 818                 reg |= MX21_CSPICTRL_POL;
 819         if (spi->mode & SPI_CS_HIGH)
 820                 reg |= MX21_CSPICTRL_SSPOL;
 821         if (!gpio_is_valid(spi->cs_gpio))
 822                 reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
 823 
 824         writel(reg, spi_imx->base + MXC_CSPICTRL);
 825 
 826         return 0;
 827 }
 828 
 829 static int mx21_rx_available(struct spi_imx_data *spi_imx)
 830 {
 831         return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
 832 }
 833 
 834 static void mx21_reset(struct spi_imx_data *spi_imx)
 835 {
 836         writel(1, spi_imx->base + MXC_RESET);
 837 }
 838 
 839 #define MX1_INTREG_RR           (1 << 3)
 840 #define MX1_INTREG_TEEN         (1 << 8)
 841 #define MX1_INTREG_RREN         (1 << 11)
 842 
 843 #define MX1_CSPICTRL_POL        (1 << 4)
 844 #define MX1_CSPICTRL_PHA        (1 << 5)
 845 #define MX1_CSPICTRL_XCH        (1 << 8)
 846 #define MX1_CSPICTRL_ENABLE     (1 << 9)
 847 #define MX1_CSPICTRL_MASTER     (1 << 10)
 848 #define MX1_CSPICTRL_DR_SHIFT   13
 849 
 850 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 851 {
 852         unsigned int val = 0;
 853 
 854         if (enable & MXC_INT_TE)
 855                 val |= MX1_INTREG_TEEN;
 856         if (enable & MXC_INT_RR)
 857                 val |= MX1_INTREG_RREN;
 858 
 859         writel(val, spi_imx->base + MXC_CSPIINT);
 860 }
 861 
 862 static void mx1_trigger(struct spi_imx_data *spi_imx)
 863 {
 864         unsigned int reg;
 865 
 866         reg = readl(spi_imx->base + MXC_CSPICTRL);
 867         reg |= MX1_CSPICTRL_XCH;
 868         writel(reg, spi_imx->base + MXC_CSPICTRL);
 869 }
 870 
 871 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
 872                                struct spi_message *msg)
 873 {
 874         return 0;
 875 }
 876 
 877 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
 878                                 struct spi_device *spi,
 879                                 struct spi_transfer *t)
 880 {
 881         unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 882         unsigned int clk;
 883 
 884         reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
 885                 MX1_CSPICTRL_DR_SHIFT;
 886         spi_imx->spi_bus_clk = clk;
 887 
 888         reg |= spi_imx->bits_per_word - 1;
 889 
 890         if (spi->mode & SPI_CPHA)
 891                 reg |= MX1_CSPICTRL_PHA;
 892         if (spi->mode & SPI_CPOL)
 893                 reg |= MX1_CSPICTRL_POL;
 894 
 895         writel(reg, spi_imx->base + MXC_CSPICTRL);
 896 
 897         return 0;
 898 }
 899 
 900 static int mx1_rx_available(struct spi_imx_data *spi_imx)
 901 {
 902         return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 903 }
 904 
 905 static void mx1_reset(struct spi_imx_data *spi_imx)
 906 {
 907         writel(1, spi_imx->base + MXC_RESET);
 908 }
 909 
 910 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 911         .intctrl = mx1_intctrl,
 912         .prepare_message = mx1_prepare_message,
 913         .prepare_transfer = mx1_prepare_transfer,
 914         .trigger = mx1_trigger,
 915         .rx_available = mx1_rx_available,
 916         .reset = mx1_reset,
 917         .fifo_size = 8,
 918         .has_dmamode = false,
 919         .dynamic_burst = false,
 920         .has_slavemode = false,
 921         .devtype = IMX1_CSPI,
 922 };
 923 
 924 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 925         .intctrl = mx21_intctrl,
 926         .prepare_message = mx21_prepare_message,
 927         .prepare_transfer = mx21_prepare_transfer,
 928         .trigger = mx21_trigger,
 929         .rx_available = mx21_rx_available,
 930         .reset = mx21_reset,
 931         .fifo_size = 8,
 932         .has_dmamode = false,
 933         .dynamic_burst = false,
 934         .has_slavemode = false,
 935         .devtype = IMX21_CSPI,
 936 };
 937 
 938 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 939         /* i.mx27 cspi shares the functions with i.mx21 one */
 940         .intctrl = mx21_intctrl,
 941         .prepare_message = mx21_prepare_message,
 942         .prepare_transfer = mx21_prepare_transfer,
 943         .trigger = mx21_trigger,
 944         .rx_available = mx21_rx_available,
 945         .reset = mx21_reset,
 946         .fifo_size = 8,
 947         .has_dmamode = false,
 948         .dynamic_burst = false,
 949         .has_slavemode = false,
 950         .devtype = IMX27_CSPI,
 951 };
 952 
 953 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 954         .intctrl = mx31_intctrl,
 955         .prepare_message = mx31_prepare_message,
 956         .prepare_transfer = mx31_prepare_transfer,
 957         .trigger = mx31_trigger,
 958         .rx_available = mx31_rx_available,
 959         .reset = mx31_reset,
 960         .fifo_size = 8,
 961         .has_dmamode = false,
 962         .dynamic_burst = false,
 963         .has_slavemode = false,
 964         .devtype = IMX31_CSPI,
 965 };
 966 
 967 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 968         /* i.mx35 and later cspi shares the functions with i.mx31 one */
 969         .intctrl = mx31_intctrl,
 970         .prepare_message = mx31_prepare_message,
 971         .prepare_transfer = mx31_prepare_transfer,
 972         .trigger = mx31_trigger,
 973         .rx_available = mx31_rx_available,
 974         .reset = mx31_reset,
 975         .fifo_size = 8,
 976         .has_dmamode = true,
 977         .dynamic_burst = false,
 978         .has_slavemode = false,
 979         .devtype = IMX35_CSPI,
 980 };
 981 
 982 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 983         .intctrl = mx51_ecspi_intctrl,
 984         .prepare_message = mx51_ecspi_prepare_message,
 985         .prepare_transfer = mx51_ecspi_prepare_transfer,
 986         .trigger = mx51_ecspi_trigger,
 987         .rx_available = mx51_ecspi_rx_available,
 988         .reset = mx51_ecspi_reset,
 989         .setup_wml = mx51_setup_wml,
 990         .fifo_size = 64,
 991         .has_dmamode = true,
 992         .dynamic_burst = true,
 993         .has_slavemode = true,
 994         .disable = mx51_ecspi_disable,
 995         .devtype = IMX51_ECSPI,
 996 };
 997 
 998 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
 999         .intctrl = mx51_ecspi_intctrl,
1000         .prepare_message = mx51_ecspi_prepare_message,
1001         .prepare_transfer = mx51_ecspi_prepare_transfer,
1002         .trigger = mx51_ecspi_trigger,
1003         .rx_available = mx51_ecspi_rx_available,
1004         .reset = mx51_ecspi_reset,
1005         .fifo_size = 64,
1006         .has_dmamode = true,
1007         .has_slavemode = true,
1008         .disable = mx51_ecspi_disable,
1009         .devtype = IMX53_ECSPI,
1010 };
1011 
1012 static const struct platform_device_id spi_imx_devtype[] = {
1013         {
1014                 .name = "imx1-cspi",
1015                 .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
1016         }, {
1017                 .name = "imx21-cspi",
1018                 .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
1019         }, {
1020                 .name = "imx27-cspi",
1021                 .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
1022         }, {
1023                 .name = "imx31-cspi",
1024                 .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
1025         }, {
1026                 .name = "imx35-cspi",
1027                 .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
1028         }, {
1029                 .name = "imx51-ecspi",
1030                 .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
1031         }, {
1032                 .name = "imx53-ecspi",
1033                 .driver_data = (kernel_ulong_t) &imx53_ecspi_devtype_data,
1034         }, {
1035                 /* sentinel */
1036         }
1037 };
1038 
1039 static const struct of_device_id spi_imx_dt_ids[] = {
1040         { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1041         { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1042         { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1043         { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1044         { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1045         { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1046         { .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1047         { /* sentinel */ }
1048 };
1049 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1050 
1051 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
1052 {
1053         int active = is_active != BITBANG_CS_INACTIVE;
1054         int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
1055 
1056         if (spi->mode & SPI_NO_CS)
1057                 return;
1058 
1059         if (!gpio_is_valid(spi->cs_gpio))
1060                 return;
1061 
1062         gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active);
1063 }
1064 
1065 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1066 {
1067         u32 ctrl;
1068 
1069         ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1070         ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1071         ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1072         writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1073 }
1074 
1075 static void spi_imx_push(struct spi_imx_data *spi_imx)
1076 {
1077         unsigned int burst_len, fifo_words;
1078 
1079         if (spi_imx->dynamic_burst)
1080                 fifo_words = 4;
1081         else
1082                 fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1083         /*
1084          * Reload the FIFO when the remaining bytes to be transferred in the
1085          * current burst is 0. This only applies when bits_per_word is a
1086          * multiple of 8.
1087          */
1088         if (!spi_imx->remainder) {
1089                 if (spi_imx->dynamic_burst) {
1090 
1091                         /* We need to deal unaligned data first */
1092                         burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1093 
1094                         if (!burst_len)
1095                                 burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1096 
1097                         spi_imx_set_burst_len(spi_imx, burst_len * 8);
1098 
1099                         spi_imx->remainder = burst_len;
1100                 } else {
1101                         spi_imx->remainder = fifo_words;
1102                 }
1103         }
1104 
1105         while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1106                 if (!spi_imx->count)
1107                         break;
1108                 if (spi_imx->dynamic_burst &&
1109                     spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
1110                                                      fifo_words))
1111                         break;
1112                 spi_imx->tx(spi_imx);
1113                 spi_imx->txfifo++;
1114         }
1115 
1116         if (!spi_imx->slave_mode)
1117                 spi_imx->devtype_data->trigger(spi_imx);
1118 }
1119 
1120 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1121 {
1122         struct spi_imx_data *spi_imx = dev_id;
1123 
1124         while (spi_imx->txfifo &&
1125                spi_imx->devtype_data->rx_available(spi_imx)) {
1126                 spi_imx->rx(spi_imx);
1127                 spi_imx->txfifo--;
1128         }
1129 
1130         if (spi_imx->count) {
1131                 spi_imx_push(spi_imx);
1132                 return IRQ_HANDLED;
1133         }
1134 
1135         if (spi_imx->txfifo) {
1136                 /* No data left to push, but still waiting for rx data,
1137                  * enable receive data available interrupt.
1138                  */
1139                 spi_imx->devtype_data->intctrl(
1140                                 spi_imx, MXC_INT_RR);
1141                 return IRQ_HANDLED;
1142         }
1143 
1144         spi_imx->devtype_data->intctrl(spi_imx, 0);
1145         complete(&spi_imx->xfer_done);
1146 
1147         return IRQ_HANDLED;
1148 }
1149 
1150 static int spi_imx_dma_configure(struct spi_master *master)
1151 {
1152         int ret;
1153         enum dma_slave_buswidth buswidth;
1154         struct dma_slave_config rx = {}, tx = {};
1155         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1156 
1157         switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1158         case 4:
1159                 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1160                 break;
1161         case 2:
1162                 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1163                 break;
1164         case 1:
1165                 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1166                 break;
1167         default:
1168                 return -EINVAL;
1169         }
1170 
1171         tx.direction = DMA_MEM_TO_DEV;
1172         tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1173         tx.dst_addr_width = buswidth;
1174         tx.dst_maxburst = spi_imx->wml;
1175         ret = dmaengine_slave_config(master->dma_tx, &tx);
1176         if (ret) {
1177                 dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1178                 return ret;
1179         }
1180 
1181         rx.direction = DMA_DEV_TO_MEM;
1182         rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1183         rx.src_addr_width = buswidth;
1184         rx.src_maxburst = spi_imx->wml;
1185         ret = dmaengine_slave_config(master->dma_rx, &rx);
1186         if (ret) {
1187                 dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1188                 return ret;
1189         }
1190 
1191         return 0;
1192 }
1193 
1194 static int spi_imx_setupxfer(struct spi_device *spi,
1195                                  struct spi_transfer *t)
1196 {
1197         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1198 
1199         if (!t)
1200                 return 0;
1201 
1202         spi_imx->bits_per_word = t->bits_per_word;
1203 
1204         /*
1205          * Initialize the functions for transfer. To transfer non byte-aligned
1206          * words, we have to use multiple word-size bursts, we can't use
1207          * dynamic_burst in that case.
1208          */
1209         if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1210             (spi_imx->bits_per_word == 8 ||
1211             spi_imx->bits_per_word == 16 ||
1212             spi_imx->bits_per_word == 32)) {
1213 
1214                 spi_imx->rx = spi_imx_buf_rx_swap;
1215                 spi_imx->tx = spi_imx_buf_tx_swap;
1216                 spi_imx->dynamic_burst = 1;
1217 
1218         } else {
1219                 if (spi_imx->bits_per_word <= 8) {
1220                         spi_imx->rx = spi_imx_buf_rx_u8;
1221                         spi_imx->tx = spi_imx_buf_tx_u8;
1222                 } else if (spi_imx->bits_per_word <= 16) {
1223                         spi_imx->rx = spi_imx_buf_rx_u16;
1224                         spi_imx->tx = spi_imx_buf_tx_u16;
1225                 } else {
1226                         spi_imx->rx = spi_imx_buf_rx_u32;
1227                         spi_imx->tx = spi_imx_buf_tx_u32;
1228                 }
1229                 spi_imx->dynamic_burst = 0;
1230         }
1231 
1232         if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1233                 spi_imx->usedma = 1;
1234         else
1235                 spi_imx->usedma = 0;
1236 
1237         if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1238                 spi_imx->rx = mx53_ecspi_rx_slave;
1239                 spi_imx->tx = mx53_ecspi_tx_slave;
1240                 spi_imx->slave_burst = t->len;
1241         }
1242 
1243         spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
1244 
1245         return 0;
1246 }
1247 
1248 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1249 {
1250         struct spi_master *master = spi_imx->bitbang.master;
1251 
1252         if (master->dma_rx) {
1253                 dma_release_channel(master->dma_rx);
1254                 master->dma_rx = NULL;
1255         }
1256 
1257         if (master->dma_tx) {
1258                 dma_release_channel(master->dma_tx);
1259                 master->dma_tx = NULL;
1260         }
1261 }
1262 
1263 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1264                              struct spi_master *master)
1265 {
1266         int ret;
1267 
1268         /* use pio mode for i.mx6dl chip TKT238285 */
1269         if (of_machine_is_compatible("fsl,imx6dl"))
1270                 return 0;
1271 
1272         spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1273 
1274         /* Prepare for TX DMA: */
1275         master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
1276         if (IS_ERR(master->dma_tx)) {
1277                 ret = PTR_ERR(master->dma_tx);
1278                 dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1279                 master->dma_tx = NULL;
1280                 goto err;
1281         }
1282 
1283         /* Prepare for RX : */
1284         master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
1285         if (IS_ERR(master->dma_rx)) {
1286                 ret = PTR_ERR(master->dma_rx);
1287                 dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1288                 master->dma_rx = NULL;
1289                 goto err;
1290         }
1291 
1292         init_completion(&spi_imx->dma_rx_completion);
1293         init_completion(&spi_imx->dma_tx_completion);
1294         master->can_dma = spi_imx_can_dma;
1295         master->max_dma_len = MAX_SDMA_BD_BYTES;
1296         spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1297                                          SPI_MASTER_MUST_TX;
1298 
1299         return 0;
1300 err:
1301         spi_imx_sdma_exit(spi_imx);
1302         return ret;
1303 }
1304 
1305 static void spi_imx_dma_rx_callback(void *cookie)
1306 {
1307         struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1308 
1309         complete(&spi_imx->dma_rx_completion);
1310 }
1311 
1312 static void spi_imx_dma_tx_callback(void *cookie)
1313 {
1314         struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1315 
1316         complete(&spi_imx->dma_tx_completion);
1317 }
1318 
1319 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1320 {
1321         unsigned long timeout = 0;
1322 
1323         /* Time with actual data transfer and CS change delay related to HW */
1324         timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1325 
1326         /* Add extra second for scheduler related activities */
1327         timeout += 1;
1328 
1329         /* Double calculated timeout */
1330         return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1331 }
1332 
1333 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1334                                 struct spi_transfer *transfer)
1335 {
1336         struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1337         unsigned long transfer_timeout;
1338         unsigned long timeout;
1339         struct spi_master *master = spi_imx->bitbang.master;
1340         struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1341         struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1342         unsigned int bytes_per_word, i;
1343         int ret;
1344 
1345         /* Get the right burst length from the last sg to ensure no tail data */
1346         bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1347         for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1348                 if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1349                         break;
1350         }
1351         /* Use 1 as wml in case no available burst length got */
1352         if (i == 0)
1353                 i = 1;
1354 
1355         spi_imx->wml =  i;
1356 
1357         ret = spi_imx_dma_configure(master);
1358         if (ret)
1359                 return ret;
1360 
1361         if (!spi_imx->devtype_data->setup_wml) {
1362                 dev_err(spi_imx->dev, "No setup_wml()?\n");
1363                 return -EINVAL;
1364         }
1365         spi_imx->devtype_data->setup_wml(spi_imx);
1366 
1367         /*
1368          * The TX DMA setup starts the transfer, so make sure RX is configured
1369          * before TX.
1370          */
1371         desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1372                                 rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1373                                 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1374         if (!desc_rx)
1375                 return -EINVAL;
1376 
1377         desc_rx->callback = spi_imx_dma_rx_callback;
1378         desc_rx->callback_param = (void *)spi_imx;
1379         dmaengine_submit(desc_rx);
1380         reinit_completion(&spi_imx->dma_rx_completion);
1381         dma_async_issue_pending(master->dma_rx);
1382 
1383         desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1384                                 tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1385                                 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1386         if (!desc_tx) {
1387                 dmaengine_terminate_all(master->dma_tx);
1388                 return -EINVAL;
1389         }
1390 
1391         desc_tx->callback = spi_imx_dma_tx_callback;
1392         desc_tx->callback_param = (void *)spi_imx;
1393         dmaengine_submit(desc_tx);
1394         reinit_completion(&spi_imx->dma_tx_completion);
1395         dma_async_issue_pending(master->dma_tx);
1396 
1397         transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1398 
1399         /* Wait SDMA to finish the data transfer.*/
1400         timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1401                                                 transfer_timeout);
1402         if (!timeout) {
1403                 dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1404                 dmaengine_terminate_all(master->dma_tx);
1405                 dmaengine_terminate_all(master->dma_rx);
1406                 return -ETIMEDOUT;
1407         }
1408 
1409         timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1410                                               transfer_timeout);
1411         if (!timeout) {
1412                 dev_err(&master->dev, "I/O Error in DMA RX\n");
1413                 spi_imx->devtype_data->reset(spi_imx);
1414                 dmaengine_terminate_all(master->dma_rx);
1415                 return -ETIMEDOUT;
1416         }
1417 
1418         return transfer->len;
1419 }
1420 
1421 static int spi_imx_pio_transfer(struct spi_device *spi,
1422                                 struct spi_transfer *transfer)
1423 {
1424         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1425         unsigned long transfer_timeout;
1426         unsigned long timeout;
1427 
1428         spi_imx->tx_buf = transfer->tx_buf;
1429         spi_imx->rx_buf = transfer->rx_buf;
1430         spi_imx->count = transfer->len;
1431         spi_imx->txfifo = 0;
1432         spi_imx->remainder = 0;
1433 
1434         reinit_completion(&spi_imx->xfer_done);
1435 
1436         spi_imx_push(spi_imx);
1437 
1438         spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1439 
1440         transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1441 
1442         timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1443                                               transfer_timeout);
1444         if (!timeout) {
1445                 dev_err(&spi->dev, "I/O Error in PIO\n");
1446                 spi_imx->devtype_data->reset(spi_imx);
1447                 return -ETIMEDOUT;
1448         }
1449 
1450         return transfer->len;
1451 }
1452 
1453 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1454                                       struct spi_transfer *transfer)
1455 {
1456         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1457         int ret = transfer->len;
1458 
1459         if (is_imx53_ecspi(spi_imx) &&
1460             transfer->len > MX53_MAX_TRANSFER_BYTES) {
1461                 dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1462                         MX53_MAX_TRANSFER_BYTES);
1463                 return -EMSGSIZE;
1464         }
1465 
1466         spi_imx->tx_buf = transfer->tx_buf;
1467         spi_imx->rx_buf = transfer->rx_buf;
1468         spi_imx->count = transfer->len;
1469         spi_imx->txfifo = 0;
1470         spi_imx->remainder = 0;
1471 
1472         reinit_completion(&spi_imx->xfer_done);
1473         spi_imx->slave_aborted = false;
1474 
1475         spi_imx_push(spi_imx);
1476 
1477         spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1478 
1479         if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1480             spi_imx->slave_aborted) {
1481                 dev_dbg(&spi->dev, "interrupted\n");
1482                 ret = -EINTR;
1483         }
1484 
1485         /* ecspi has a HW issue when works in Slave mode,
1486          * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1487          * ECSPI_TXDATA keeps shift out the last word data,
1488          * so we have to disable ECSPI when in slave mode after the
1489          * transfer completes
1490          */
1491         if (spi_imx->devtype_data->disable)
1492                 spi_imx->devtype_data->disable(spi_imx);
1493 
1494         return ret;
1495 }
1496 
1497 static int spi_imx_transfer(struct spi_device *spi,
1498                                 struct spi_transfer *transfer)
1499 {
1500         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1501 
1502         /* flush rxfifo before transfer */
1503         while (spi_imx->devtype_data->rx_available(spi_imx))
1504                 readl(spi_imx->base + MXC_CSPIRXDATA);
1505 
1506         if (spi_imx->slave_mode)
1507                 return spi_imx_pio_transfer_slave(spi, transfer);
1508 
1509         if (spi_imx->usedma)
1510                 return spi_imx_dma_transfer(spi_imx, transfer);
1511         else
1512                 return spi_imx_pio_transfer(spi, transfer);
1513 }
1514 
1515 static int spi_imx_setup(struct spi_device *spi)
1516 {
1517         dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1518                  spi->mode, spi->bits_per_word, spi->max_speed_hz);
1519 
1520         if (spi->mode & SPI_NO_CS)
1521                 return 0;
1522 
1523         if (gpio_is_valid(spi->cs_gpio))
1524                 gpio_direction_output(spi->cs_gpio,
1525                                       spi->mode & SPI_CS_HIGH ? 0 : 1);
1526 
1527         spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1528 
1529         return 0;
1530 }
1531 
1532 static void spi_imx_cleanup(struct spi_device *spi)
1533 {
1534 }
1535 
1536 static int
1537 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1538 {
1539         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1540         int ret;
1541 
1542         ret = clk_enable(spi_imx->clk_per);
1543         if (ret)
1544                 return ret;
1545 
1546         ret = clk_enable(spi_imx->clk_ipg);
1547         if (ret) {
1548                 clk_disable(spi_imx->clk_per);
1549                 return ret;
1550         }
1551 
1552         ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1553         if (ret) {
1554                 clk_disable(spi_imx->clk_ipg);
1555                 clk_disable(spi_imx->clk_per);
1556         }
1557 
1558         return ret;
1559 }
1560 
1561 static int
1562 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1563 {
1564         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1565 
1566         clk_disable(spi_imx->clk_ipg);
1567         clk_disable(spi_imx->clk_per);
1568         return 0;
1569 }
1570 
1571 static int spi_imx_slave_abort(struct spi_master *master)
1572 {
1573         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1574 
1575         spi_imx->slave_aborted = true;
1576         complete(&spi_imx->xfer_done);
1577 
1578         return 0;
1579 }
1580 
1581 static int spi_imx_probe(struct platform_device *pdev)
1582 {
1583         struct device_node *np = pdev->dev.of_node;
1584         const struct of_device_id *of_id =
1585                         of_match_device(spi_imx_dt_ids, &pdev->dev);
1586         struct spi_imx_master *mxc_platform_info =
1587                         dev_get_platdata(&pdev->dev);
1588         struct spi_master *master;
1589         struct spi_imx_data *spi_imx;
1590         struct resource *res;
1591         int i, ret, irq, spi_drctl;
1592         const struct spi_imx_devtype_data *devtype_data = of_id ? of_id->data :
1593                 (struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1594         bool slave_mode;
1595 
1596         if (!np && !mxc_platform_info) {
1597                 dev_err(&pdev->dev, "can't get the platform data\n");
1598                 return -EINVAL;
1599         }
1600 
1601         slave_mode = devtype_data->has_slavemode &&
1602                         of_property_read_bool(np, "spi-slave");
1603         if (slave_mode)
1604                 master = spi_alloc_slave(&pdev->dev,
1605                                          sizeof(struct spi_imx_data));
1606         else
1607                 master = spi_alloc_master(&pdev->dev,
1608                                           sizeof(struct spi_imx_data));
1609         if (!master)
1610                 return -ENOMEM;
1611 
1612         ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1613         if ((ret < 0) || (spi_drctl >= 0x3)) {
1614                 /* '11' is reserved */
1615                 spi_drctl = 0;
1616         }
1617 
1618         platform_set_drvdata(pdev, master);
1619 
1620         master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1621         master->bus_num = np ? -1 : pdev->id;
1622 
1623         spi_imx = spi_master_get_devdata(master);
1624         spi_imx->bitbang.master = master;
1625         spi_imx->dev = &pdev->dev;
1626         spi_imx->slave_mode = slave_mode;
1627 
1628         spi_imx->devtype_data = devtype_data;
1629 
1630         /* Get number of chip selects, either platform data or OF */
1631         if (mxc_platform_info) {
1632                 master->num_chipselect = mxc_platform_info->num_chipselect;
1633                 if (mxc_platform_info->chipselect) {
1634                         master->cs_gpios = devm_kcalloc(&master->dev,
1635                                 master->num_chipselect, sizeof(int),
1636                                 GFP_KERNEL);
1637                         if (!master->cs_gpios)
1638                                 return -ENOMEM;
1639 
1640                         for (i = 0; i < master->num_chipselect; i++)
1641                                 master->cs_gpios[i] = mxc_platform_info->chipselect[i];
1642                 }
1643         } else {
1644                 u32 num_cs;
1645 
1646                 if (!of_property_read_u32(np, "num-cs", &num_cs))
1647                         master->num_chipselect = num_cs;
1648                 /* If not preset, default value of 1 is used */
1649         }
1650 
1651         spi_imx->bitbang.chipselect = spi_imx_chipselect;
1652         spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1653         spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1654         spi_imx->bitbang.master->setup = spi_imx_setup;
1655         spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1656         spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1657         spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1658         spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1659         spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1660                                              | SPI_NO_CS;
1661         if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1662             is_imx53_ecspi(spi_imx))
1663                 spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1664 
1665         spi_imx->spi_drctl = spi_drctl;
1666 
1667         init_completion(&spi_imx->xfer_done);
1668 
1669         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1670         spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1671         if (IS_ERR(spi_imx->base)) {
1672                 ret = PTR_ERR(spi_imx->base);
1673                 goto out_master_put;
1674         }
1675         spi_imx->base_phys = res->start;
1676 
1677         irq = platform_get_irq(pdev, 0);
1678         if (irq < 0) {
1679                 ret = irq;
1680                 goto out_master_put;
1681         }
1682 
1683         ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1684                                dev_name(&pdev->dev), spi_imx);
1685         if (ret) {
1686                 dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1687                 goto out_master_put;
1688         }
1689 
1690         spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1691         if (IS_ERR(spi_imx->clk_ipg)) {
1692                 ret = PTR_ERR(spi_imx->clk_ipg);
1693                 goto out_master_put;
1694         }
1695 
1696         spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1697         if (IS_ERR(spi_imx->clk_per)) {
1698                 ret = PTR_ERR(spi_imx->clk_per);
1699                 goto out_master_put;
1700         }
1701 
1702         ret = clk_prepare_enable(spi_imx->clk_per);
1703         if (ret)
1704                 goto out_master_put;
1705 
1706         ret = clk_prepare_enable(spi_imx->clk_ipg);
1707         if (ret)
1708                 goto out_put_per;
1709 
1710         spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1711         /*
1712          * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1713          * if validated on other chips.
1714          */
1715         if (spi_imx->devtype_data->has_dmamode) {
1716                 ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1717                 if (ret == -EPROBE_DEFER)
1718                         goto out_clk_put;
1719 
1720                 if (ret < 0)
1721                         dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1722                                 ret);
1723         }
1724 
1725         spi_imx->devtype_data->reset(spi_imx);
1726 
1727         spi_imx->devtype_data->intctrl(spi_imx, 0);
1728 
1729         master->dev.of_node = pdev->dev.of_node;
1730         ret = spi_bitbang_start(&spi_imx->bitbang);
1731         if (ret) {
1732                 dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1733                 goto out_clk_put;
1734         }
1735 
1736         /* Request GPIO CS lines, if any */
1737         if (!spi_imx->slave_mode && master->cs_gpios) {
1738                 for (i = 0; i < master->num_chipselect; i++) {
1739                         if (!gpio_is_valid(master->cs_gpios[i]))
1740                                 continue;
1741 
1742                         ret = devm_gpio_request(&pdev->dev,
1743                                                 master->cs_gpios[i],
1744                                                 DRIVER_NAME);
1745                         if (ret) {
1746                                 dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
1747                                         master->cs_gpios[i]);
1748                                 goto out_spi_bitbang;
1749                         }
1750                 }
1751         }
1752 
1753         dev_info(&pdev->dev, "probed\n");
1754 
1755         clk_disable(spi_imx->clk_ipg);
1756         clk_disable(spi_imx->clk_per);
1757         return ret;
1758 
1759 out_spi_bitbang:
1760         spi_bitbang_stop(&spi_imx->bitbang);
1761 out_clk_put:
1762         clk_disable_unprepare(spi_imx->clk_ipg);
1763 out_put_per:
1764         clk_disable_unprepare(spi_imx->clk_per);
1765 out_master_put:
1766         spi_master_put(master);
1767 
1768         return ret;
1769 }
1770 
1771 static int spi_imx_remove(struct platform_device *pdev)
1772 {
1773         struct spi_master *master = platform_get_drvdata(pdev);
1774         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1775         int ret;
1776 
1777         spi_bitbang_stop(&spi_imx->bitbang);
1778 
1779         ret = clk_enable(spi_imx->clk_per);
1780         if (ret)
1781                 return ret;
1782 
1783         ret = clk_enable(spi_imx->clk_ipg);
1784         if (ret) {
1785                 clk_disable(spi_imx->clk_per);
1786                 return ret;
1787         }
1788 
1789         writel(0, spi_imx->base + MXC_CSPICTRL);
1790         clk_disable_unprepare(spi_imx->clk_ipg);
1791         clk_disable_unprepare(spi_imx->clk_per);
1792         spi_imx_sdma_exit(spi_imx);
1793         spi_master_put(master);
1794 
1795         return 0;
1796 }
1797 
1798 static struct platform_driver spi_imx_driver = {
1799         .driver = {
1800                    .name = DRIVER_NAME,
1801                    .of_match_table = spi_imx_dt_ids,
1802                    },
1803         .id_table = spi_imx_devtype,
1804         .probe = spi_imx_probe,
1805         .remove = spi_imx_remove,
1806 };
1807 module_platform_driver(spi_imx_driver);
1808 
1809 MODULE_DESCRIPTION("SPI Controller driver");
1810 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1811 MODULE_LICENSE("GPL");
1812 MODULE_ALIAS("platform:" DRIVER_NAME);
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/spi/spi-imx.c

DEFINITIONS
