drivers/spi/spi-orion.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Marvell Orion SPI controller driver
   4  *
   5  * Author: Shadi Ammouri <shadi@marvell.com>
   6  * Copyright (C) 2007-2008 Marvell Ltd.
   7  */
   8
   9 #include <linux/interrupt.h>
  10 #include <linux/delay.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/err.h>
  13 #include <linux/io.h>
  14 #include <linux/spi/spi.h>
  15 #include <linux/module.h>
  16 #include <linux/pm_runtime.h>
  17 #include <linux/of.h>
  18 #include <linux/of_address.h>
  19 #include <linux/of_device.h>
  20 #include <linux/clk.h>
  21 #include <linux/sizes.h>
  22 #include <asm/unaligned.h>
  23
  24 #define DRIVER_NAME                     "orion_spi"
  25
  26 /* Runtime PM autosuspend timeout: PM is fairly light on this driver */
  27 #define SPI_AUTOSUSPEND_TIMEOUT         200
  28
  29 /* Some SoCs using this driver support up to 8 chip selects.
  30  * It is up to the implementer to only use the chip selects
  31  * that are available.
  32  */
  33 #define ORION_NUM_CHIPSELECTS           8
  34
  35 #define ORION_SPI_WAIT_RDY_MAX_LOOP     2000 /* in usec */
  36
  37 #define ORION_SPI_IF_CTRL_REG           0x00
  38 #define ORION_SPI_IF_CONFIG_REG         0x04
  39 #define ORION_SPI_IF_RXLSBF             BIT(14)
  40 #define ORION_SPI_IF_TXLSBF             BIT(13)
  41 #define ORION_SPI_DATA_OUT_REG          0x08
  42 #define ORION_SPI_DATA_IN_REG           0x0c
  43 #define ORION_SPI_INT_CAUSE_REG         0x10
  44 #define ORION_SPI_TIMING_PARAMS_REG     0x18
  45
  46 /* Register for the "Direct Mode" */
  47 #define SPI_DIRECT_WRITE_CONFIG_REG     0x20
  48
  49 #define ORION_SPI_TMISO_SAMPLE_MASK     (0x3 << 6)
  50 #define ORION_SPI_TMISO_SAMPLE_1        (1 << 6)
  51 #define ORION_SPI_TMISO_SAMPLE_2        (2 << 6)
  52
  53 #define ORION_SPI_MODE_CPOL             (1 << 11)
  54 #define ORION_SPI_MODE_CPHA             (1 << 12)
  55 #define ORION_SPI_IF_8_16_BIT_MODE      (1 << 5)
  56 #define ORION_SPI_CLK_PRESCALE_MASK     0x1F
  57 #define ARMADA_SPI_CLK_PRESCALE_MASK    0xDF
  58 #define ORION_SPI_MODE_MASK             (ORION_SPI_MODE_CPOL | \
  59                                          ORION_SPI_MODE_CPHA)
  60 #define ORION_SPI_CS_MASK       0x1C
  61 #define ORION_SPI_CS_SHIFT      2
  62 #define ORION_SPI_CS(cs)        ((cs << ORION_SPI_CS_SHIFT) & \
  63                                         ORION_SPI_CS_MASK)
  64
  65 enum orion_spi_type {
  66         ORION_SPI,
  67         ARMADA_SPI,
  68 };
  69
  70 struct orion_spi_dev {
  71         enum orion_spi_type     typ;
  72         /*
  73          * min_divisor and max_hz should be exclusive, the only we can
  74          * have both is for managing the armada-370-spi case with old
  75          * device tree
  76          */
  77         unsigned long           max_hz;
  78         unsigned int            min_divisor;
  79         unsigned int            max_divisor;
  80         u32                     prescale_mask;
  81         bool                    is_errata_50mhz_ac;
  82 };
  83
  84 struct orion_direct_acc {
  85         void __iomem            *vaddr;
  86         u32                     size;
  87 };
  88
  89 struct orion_child_options {
  90         struct orion_direct_acc direct_access;
  91 };
  92
  93 struct orion_spi {
  94         struct spi_master       *master;
  95         void __iomem            *base;
  96         struct clk              *clk;
  97         struct clk              *axi_clk;
  98         const struct orion_spi_dev *devdata;
  99         struct device           *dev;
 100
 101         struct orion_child_options      child[ORION_NUM_CHIPSELECTS];
 102 };
 103
 104 #ifdef CONFIG_PM
 105 static int orion_spi_runtime_suspend(struct device *dev);
 106 static int orion_spi_runtime_resume(struct device *dev);
 107 #endif
 108
 109 static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg)
 110 {
 111         return orion_spi->base + reg;
 112 }
 113
 114 static inline void
 115 orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
 116 {
 117         void __iomem *reg_addr = spi_reg(orion_spi, reg);
 118         u32 val;
 119
 120         val = readl(reg_addr);
 121         val |= mask;
 122         writel(val, reg_addr);
 123 }
 124
 125 static inline void
 126 orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
 127 {
 128         void __iomem *reg_addr = spi_reg(orion_spi, reg);
 129         u32 val;
 130
 131         val = readl(reg_addr);
 132         val &= ~mask;
 133         writel(val, reg_addr);
 134 }
 135
 136 static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
 137 {
 138         u32 tclk_hz;
 139         u32 rate;
 140         u32 prescale;
 141         u32 reg;
 142         struct orion_spi *orion_spi;
 143         const struct orion_spi_dev *devdata;
 144
 145         orion_spi = spi_master_get_devdata(spi->master);
 146         devdata = orion_spi->devdata;
 147
 148         tclk_hz = clk_get_rate(orion_spi->clk);
 149
 150         if (devdata->typ == ARMADA_SPI) {
 151                 /*
 152                  * Given the core_clk (tclk_hz) and the target rate (speed) we
 153                  * determine the best values for SPR (in [0 .. 15]) and SPPR (in
 154                  * [0..7]) such that
 155                  *
 156                  *      core_clk / (SPR * 2 ** SPPR)
 157                  *
 158                  * is as big as possible but not bigger than speed.
 159                  */
 160
 161                 /* best integer divider: */
 162                 unsigned divider = DIV_ROUND_UP(tclk_hz, speed);
 163                 unsigned spr, sppr;
 164
 165                 if (divider < 16) {
 166                         /* This is the easy case, divider is less than 16 */
 167                         spr = divider;
 168                         sppr = 0;
 169
 170                 } else {
 171                         unsigned two_pow_sppr;
 172                         /*
 173                          * Find the highest bit set in divider. This and the
 174                          * three next bits define SPR (apart from rounding).
 175                          * SPPR is then the number of zero bits that must be
 176                          * appended:
 177                          */
 178                         sppr = fls(divider) - 4;
 179
 180                         /*
 181                          * As SPR only has 4 bits, we have to round divider up
 182                          * to the next multiple of 2 ** sppr.
 183                          */
 184                         two_pow_sppr = 1 << sppr;
 185                         divider = (divider + two_pow_sppr - 1) & -two_pow_sppr;
 186
 187                         /*
 188                          * recalculate sppr as rounding up divider might have
 189                          * increased it enough to change the position of the
 190                          * highest set bit. In this case the bit that now
 191                          * doesn't make it into SPR is 0, so there is no need to
 192                          * round again.
 193                          */
 194                         sppr = fls(divider) - 4;
 195                         spr = divider >> sppr;
 196
 197                         /*
 198                          * Now do range checking. SPR is constructed to have a
 199                          * width of 4 bits, so this is fine for sure. So we
 200                          * still need to check for sppr to fit into 3 bits:
 201                          */
 202                         if (sppr > 7)
 203                                 return -EINVAL;
 204                 }
 205
 206                 prescale = ((sppr & 0x6) << 5) | ((sppr & 0x1) << 4) | spr;
 207         } else {
 208                 /*
 209                  * the supported rates are: 4,6,8...30
 210                  * round up as we look for equal or less speed
 211                  */
 212                 rate = DIV_ROUND_UP(tclk_hz, speed);
 213                 rate = roundup(rate, 2);
 214
 215                 /* check if requested speed is too small */
 216                 if (rate > 30)
 217                         return -EINVAL;
 218
 219                 if (rate < 4)
 220                         rate = 4;
 221
 222                 /* Convert the rate to SPI clock divisor value. */
 223                 prescale = 0x10 + rate/2;
 224         }
 225
 226         reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
 227         reg = ((reg & ~devdata->prescale_mask) | prescale);
 228         writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
 229
 230         return 0;
 231 }
 232
 233 static void
 234 orion_spi_mode_set(struct spi_device *spi)
 235 {
 236         u32 reg;
 237         struct orion_spi *orion_spi;
 238
 239         orion_spi = spi_master_get_devdata(spi->master);
 240
 241         reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
 242         reg &= ~ORION_SPI_MODE_MASK;
 243         if (spi->mode & SPI_CPOL)
 244                 reg |= ORION_SPI_MODE_CPOL;
 245         if (spi->mode & SPI_CPHA)
 246                 reg |= ORION_SPI_MODE_CPHA;
 247         if (spi->mode & SPI_LSB_FIRST)
 248                 reg |= ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF;
 249         else
 250                 reg &= ~(ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF);
 251
 252         writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
 253 }
 254
 255 static void
 256 orion_spi_50mhz_ac_timing_erratum(struct spi_device *spi, unsigned int speed)
 257 {
 258         u32 reg;
 259         struct orion_spi *orion_spi;
 260
 261         orion_spi = spi_master_get_devdata(spi->master);
 262
 263         /*
 264          * Erratum description: (Erratum NO. FE-9144572) The device
 265          * SPI interface supports frequencies of up to 50 MHz.
 266          * However, due to this erratum, when the device core clock is
 267          * 250 MHz and the SPI interfaces is configured for 50MHz SPI
 268          * clock and CPOL=CPHA=1 there might occur data corruption on
 269          * reads from the SPI device.
 270          * Erratum Workaround:
 271          * Work in one of the following configurations:
 272          * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
 273          * Register".
 274          * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
 275          * Register" before setting the interface.
 276          */
 277         reg = readl(spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
 278         reg &= ~ORION_SPI_TMISO_SAMPLE_MASK;
 279
 280         if (clk_get_rate(orion_spi->clk) == 250000000 &&
 281                         speed == 50000000 && spi->mode & SPI_CPOL &&
 282                         spi->mode & SPI_CPHA)
 283                 reg |= ORION_SPI_TMISO_SAMPLE_2;
 284         else
 285                 reg |= ORION_SPI_TMISO_SAMPLE_1; /* This is the default value */
 286
 287         writel(reg, spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
 288 }
 289
 290 /*
 291  * called only when no transfer is active on the bus
 292  */
 293 static int
 294 orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
 295 {
 296         struct orion_spi *orion_spi;
 297         unsigned int speed = spi->max_speed_hz;
 298         unsigned int bits_per_word = spi->bits_per_word;
 299         int     rc;
 300
 301         orion_spi = spi_master_get_devdata(spi->master);
 302
 303         if ((t != NULL) && t->speed_hz)
 304                 speed = t->speed_hz;
 305
 306         if ((t != NULL) && t->bits_per_word)
 307                 bits_per_word = t->bits_per_word;
 308
 309         orion_spi_mode_set(spi);
 310
 311         if (orion_spi->devdata->is_errata_50mhz_ac)
 312                 orion_spi_50mhz_ac_timing_erratum(spi, speed);
 313
 314         rc = orion_spi_baudrate_set(spi, speed);
 315         if (rc)
 316                 return rc;
 317
 318         if (bits_per_word == 16)
 319                 orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
 320                                   ORION_SPI_IF_8_16_BIT_MODE);
 321         else
 322                 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
 323                                   ORION_SPI_IF_8_16_BIT_MODE);
 324
 325         return 0;
 326 }
 327
 328 static void orion_spi_set_cs(struct spi_device *spi, bool enable)
 329 {
 330         struct orion_spi *orion_spi;
 331
 332         orion_spi = spi_master_get_devdata(spi->master);
 333
 334         /*
 335          * If this line is using a GPIO to control chip select, this internal
 336          * .set_cs() function will still be called, so we clear any previous
 337          * chip select. The CS we activate will not have any elecrical effect,
 338          * as it is handled by a GPIO, but that doesn't matter. What we need
 339          * is to deassert the old chip select and assert some other chip select.
 340          */
 341         orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK);
 342         orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG,
 343                           ORION_SPI_CS(spi->chip_select));
 344
 345         /*
 346          * Chip select logic is inverted from spi_set_cs(). For lines using a
 347          * GPIO to do chip select SPI_CS_HIGH is enforced and inversion happens
 348          * in the GPIO library, but we don't care about that, because in those
 349          * cases we are dealing with an unused native CS anyways so the polarity
 350          * doesn't matter.
 351          */
 352         if (!enable)
 353                 orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
 354         else
 355                 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
 356 }
 357
 358 static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi)
 359 {
 360         int i;
 361
 362         for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) {
 363                 if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG)))
 364                         return 1;
 365
 366                 udelay(1);
 367         }
 368
 369         return -1;
 370 }
 371
 372 static inline int
 373 orion_spi_write_read_8bit(struct spi_device *spi,
 374                           const u8 **tx_buf, u8 **rx_buf)
 375 {
 376         void __iomem *tx_reg, *rx_reg, *int_reg;
 377         struct orion_spi *orion_spi;
 378         bool cs_single_byte;
 379
 380         cs_single_byte = spi->mode & SPI_CS_WORD;
 381
 382         orion_spi = spi_master_get_devdata(spi->master);
 383
 384         if (cs_single_byte)
 385                 orion_spi_set_cs(spi, 0);
 386
 387         tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
 388         rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
 389         int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
 390
 391         /* clear the interrupt cause register */
 392         writel(0x0, int_reg);
 393
 394         if (tx_buf && *tx_buf)
 395                 writel(*(*tx_buf)++, tx_reg);
 396         else
 397                 writel(0, tx_reg);
 398
 399         if (orion_spi_wait_till_ready(orion_spi) < 0) {
 400                 if (cs_single_byte) {
 401                         orion_spi_set_cs(spi, 1);
 402                         /* Satisfy some SLIC devices requirements */
 403                         udelay(4);
 404                 }
 405                 dev_err(&spi->dev, "TXS timed out\n");
 406                 return -1;
 407         }
 408
 409         if (rx_buf && *rx_buf)
 410                 *(*rx_buf)++ = readl(rx_reg);
 411
 412         if (cs_single_byte) {
 413                 orion_spi_set_cs(spi, 1);
 414                 /* Satisfy some SLIC devices requirements */
 415                 udelay(4);
 416         }
 417
 418         return 1;
 419 }
 420
 421 static inline int
 422 orion_spi_write_read_16bit(struct spi_device *spi,
 423                            const u16 **tx_buf, u16 **rx_buf)
 424 {
 425         void __iomem *tx_reg, *rx_reg, *int_reg;
 426         struct orion_spi *orion_spi;
 427
 428         if (spi->mode & SPI_CS_WORD) {
 429                 dev_err(&spi->dev, "SPI_CS_WORD is only supported for 8 bit words\n");
 430                 return -1;
 431         }
 432
 433         orion_spi = spi_master_get_devdata(spi->master);
 434         tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
 435         rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
 436         int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
 437
 438         /* clear the interrupt cause register */
 439         writel(0x0, int_reg);
 440
 441         if (tx_buf && *tx_buf)
 442                 writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg);
 443         else
 444                 writel(0, tx_reg);
 445
 446         if (orion_spi_wait_till_ready(orion_spi) < 0) {
 447                 dev_err(&spi->dev, "TXS timed out\n");
 448                 return -1;
 449         }
 450
 451         if (rx_buf && *rx_buf)
 452                 put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++);
 453
 454         return 1;
 455 }
 456
 457 static unsigned int
 458 orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
 459 {
 460         unsigned int count;
 461         int word_len;
 462         struct orion_spi *orion_spi;
 463         int cs = spi->chip_select;
 464         void __iomem *vaddr;
 465
 466         word_len = spi->bits_per_word;
 467         count = xfer->len;
 468
 469         orion_spi = spi_master_get_devdata(spi->master);
 470
 471         /*
 472          * Use SPI direct write mode if base address is available
 473          * and SPI_CS_WORD flag is not set.
 474          * Otherwise fall back to PIO mode for this transfer.
 475          */
 476         vaddr = orion_spi->child[cs].direct_access.vaddr;
 477
 478         if (vaddr && xfer->tx_buf && word_len == 8 && (spi->mode & SPI_CS_WORD) == 0) {
 479                 unsigned int cnt = count / 4;
 480                 unsigned int rem = count % 4;
 481
 482                 /*
 483                  * Send the TX-data to the SPI device via the direct
 484                  * mapped address window
 485                  */
 486                 iowrite32_rep(vaddr, xfer->tx_buf, cnt);
 487                 if (rem) {
 488                         u32 *buf = (u32 *)xfer->tx_buf;
 489
 490                         iowrite8_rep(vaddr, &buf[cnt], rem);
 491                 }
 492
 493                 return count;
 494         }
 495
 496         if (word_len == 8) {
 497                 const u8 *tx = xfer->tx_buf;
 498                 u8 *rx = xfer->rx_buf;
 499
 500                 do {
 501                         if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0)
 502                                 goto out;
 503                         count--;
 504                         spi_delay_exec(&xfer->word_delay, xfer);
 505                 } while (count);
 506         } else if (word_len == 16) {
 507                 const u16 *tx = xfer->tx_buf;
 508                 u16 *rx = xfer->rx_buf;
 509
 510                 do {
 511                         if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0)
 512                                 goto out;
 513                         count -= 2;
 514                         spi_delay_exec(&xfer->word_delay, xfer);
 515                 } while (count);
 516         }
 517
 518 out:
 519         return xfer->len - count;
 520 }
 521
 522 static int orion_spi_transfer_one(struct spi_master *master,
 523                                         struct spi_device *spi,
 524                                         struct spi_transfer *t)
 525 {
 526         int status = 0;
 527
 528         status = orion_spi_setup_transfer(spi, t);
 529         if (status < 0)
 530                 return status;
 531
 532         if (t->len)
 533                 orion_spi_write_read(spi, t);
 534
 535         return status;
 536 }
 537
 538 static int orion_spi_setup(struct spi_device *spi)
 539 {
 540         int ret;
 541 #ifdef CONFIG_PM
 542         struct orion_spi *orion_spi = spi_master_get_devdata(spi->master);
 543         struct device *dev = orion_spi->dev;
 544
 545         orion_spi_runtime_resume(dev);
 546 #endif
 547
 548         ret = orion_spi_setup_transfer(spi, NULL);
 549
 550 #ifdef CONFIG_PM
 551         orion_spi_runtime_suspend(dev);
 552 #endif
 553
 554         return ret;
 555 }
 556
 557 static int orion_spi_reset(struct orion_spi *orion_spi)
 558 {
 559         /* Verify that the CS is deasserted */
 560         orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
 561
 562         /* Don't deassert CS between the direct mapped SPI transfers */
 563         writel(0, spi_reg(orion_spi, SPI_DIRECT_WRITE_CONFIG_REG));
 564
 565         return 0;
 566 }
 567
 568 static const struct orion_spi_dev orion_spi_dev_data = {
 569         .typ = ORION_SPI,
 570         .min_divisor = 4,
 571         .max_divisor = 30,
 572         .prescale_mask = ORION_SPI_CLK_PRESCALE_MASK,
 573 };
 574
 575 static const struct orion_spi_dev armada_370_spi_dev_data = {
 576         .typ = ARMADA_SPI,
 577         .min_divisor = 4,
 578         .max_divisor = 1920,
 579         .max_hz = 50000000,
 580         .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
 581 };
 582
 583 static const struct orion_spi_dev armada_xp_spi_dev_data = {
 584         .typ = ARMADA_SPI,
 585         .max_hz = 50000000,
 586         .max_divisor = 1920,
 587         .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
 588 };
 589
 590 static const struct orion_spi_dev armada_375_spi_dev_data = {
 591         .typ = ARMADA_SPI,
 592         .min_divisor = 15,
 593         .max_divisor = 1920,
 594         .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
 595 };
 596
 597 static const struct orion_spi_dev armada_380_spi_dev_data = {
 598         .typ = ARMADA_SPI,
 599         .max_hz = 50000000,
 600         .max_divisor = 1920,
 601         .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
 602         .is_errata_50mhz_ac = true,
 603 };
 604
 605 static const struct of_device_id orion_spi_of_match_table[] = {
 606         {
 607                 .compatible = "marvell,orion-spi",
 608                 .data = &orion_spi_dev_data,
 609         },
 610         {
 611                 .compatible = "marvell,armada-370-spi",
 612                 .data = &armada_370_spi_dev_data,
 613         },
 614         {
 615                 .compatible = "marvell,armada-375-spi",
 616                 .data = &armada_375_spi_dev_data,
 617         },
 618         {
 619                 .compatible = "marvell,armada-380-spi",
 620                 .data = &armada_380_spi_dev_data,
 621         },
 622         {
 623                 .compatible = "marvell,armada-390-spi",
 624                 .data = &armada_xp_spi_dev_data,
 625         },
 626         {
 627                 .compatible = "marvell,armada-xp-spi",
 628                 .data = &armada_xp_spi_dev_data,
 629         },
 630
 631         {}
 632 };
 633 MODULE_DEVICE_TABLE(of, orion_spi_of_match_table);
 634
 635 static int orion_spi_probe(struct platform_device *pdev)
 636 {
 637         const struct orion_spi_dev *devdata;
 638         struct spi_master *master;
 639         struct orion_spi *spi;
 640         struct resource *r;
 641         unsigned long tclk_hz;
 642         int status = 0;
 643         struct device_node *np;
 644
 645         master = spi_alloc_master(&pdev->dev, sizeof(*spi));
 646         if (master == NULL) {
 647                 dev_dbg(&pdev->dev, "master allocation failed\n");
 648                 return -ENOMEM;
 649         }
 650
 651         if (pdev->id != -1)
 652                 master->bus_num = pdev->id;
 653         if (pdev->dev.of_node) {
 654                 u32 cell_index;
 655
 656                 if (!of_property_read_u32(pdev->dev.of_node, "cell-index",
 657                                           &cell_index))
 658                         master->bus_num = cell_index;
 659         }
 660
 661         /* we support all 4 SPI modes and LSB first option */
 662         master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST | SPI_CS_WORD;
 663         master->set_cs = orion_spi_set_cs;
 664         master->transfer_one = orion_spi_transfer_one;
 665         master->num_chipselect = ORION_NUM_CHIPSELECTS;
 666         master->setup = orion_spi_setup;
 667         master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
 668         master->auto_runtime_pm = true;
 669         master->use_gpio_descriptors = true;
 670         master->flags = SPI_MASTER_GPIO_SS;
 671
 672         platform_set_drvdata(pdev, master);
 673
 674         spi = spi_master_get_devdata(master);
 675         spi->master = master;
 676         spi->dev = &pdev->dev;
 677
 678         devdata = device_get_match_data(&pdev->dev);
 679         devdata = devdata ? devdata : &orion_spi_dev_data;
 680         spi->devdata = devdata;
 681
 682         spi->clk = devm_clk_get(&pdev->dev, NULL);
 683         if (IS_ERR(spi->clk)) {
 684                 status = PTR_ERR(spi->clk);
 685                 goto out;
 686         }
 687
 688         status = clk_prepare_enable(spi->clk);
 689         if (status)
 690                 goto out;
 691
 692         /* The following clock is only used by some SoCs */
 693         spi->axi_clk = devm_clk_get(&pdev->dev, "axi");
 694         if (PTR_ERR(spi->axi_clk) == -EPROBE_DEFER) {
 695                 status = -EPROBE_DEFER;
 696                 goto out_rel_clk;
 697         }
 698         if (!IS_ERR(spi->axi_clk))
 699                 clk_prepare_enable(spi->axi_clk);
 700
 701         tclk_hz = clk_get_rate(spi->clk);
 702
 703         /*
 704          * With old device tree, armada-370-spi could be used with
 705          * Armada XP, however for this SoC the maximum frequency is
 706          * 50MHz instead of tclk/4. On Armada 370, tclk cannot be
 707          * higher than 200MHz. So, in order to be able to handle both
 708          * SoCs, we can take the minimum of 50MHz and tclk/4.
 709          */
 710         if (of_device_is_compatible(pdev->dev.of_node,
 711                                         "marvell,armada-370-spi"))
 712                 master->max_speed_hz = min(devdata->max_hz,
 713                                 DIV_ROUND_UP(tclk_hz, devdata->min_divisor));
 714         else if (devdata->min_divisor)
 715                 master->max_speed_hz =
 716                         DIV_ROUND_UP(tclk_hz, devdata->min_divisor);
 717         else
 718                 master->max_speed_hz = devdata->max_hz;
 719         master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor);
 720
 721         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 722         spi->base = devm_ioremap_resource(&pdev->dev, r);
 723         if (IS_ERR(spi->base)) {
 724                 status = PTR_ERR(spi->base);
 725                 goto out_rel_axi_clk;
 726         }
 727
 728         for_each_available_child_of_node(pdev->dev.of_node, np) {
 729                 struct orion_direct_acc *dir_acc;
 730                 u32 cs;
 731
 732                 /* Get chip-select number from the "reg" property */
 733                 status = of_property_read_u32(np, "reg", &cs);
 734                 if (status) {
 735                         dev_err(&pdev->dev,
 736                                 "%pOF has no valid 'reg' property (%d)\n",
 737                                 np, status);
 738                         continue;
 739                 }
 740
 741                 /*
 742                  * Check if an address is configured for this SPI device. If
 743                  * not, the MBus mapping via the 'ranges' property in the 'soc'
 744                  * node is not configured and this device should not use the
 745                  * direct mode. In this case, just continue with the next
 746                  * device.
 747                  */
 748                 status = of_address_to_resource(pdev->dev.of_node, cs + 1, r);
 749                 if (status)
 750                         continue;
 751
 752                 /*
 753                  * Only map one page for direct access. This is enough for the
 754                  * simple TX transfer which only writes to the first word.
 755                  * This needs to get extended for the direct SPI NOR / SPI NAND
 756                  * support, once this gets implemented.
 757                  */
 758                 dir_acc = &spi->child[cs].direct_access;
 759                 dir_acc->vaddr = devm_ioremap(&pdev->dev, r->start, PAGE_SIZE);
 760                 if (!dir_acc->vaddr) {
 761                         status = -ENOMEM;
 762                         goto out_rel_axi_clk;
 763                 }
 764                 dir_acc->size = PAGE_SIZE;
 765
 766                 dev_info(&pdev->dev, "CS%d configured for direct access\n", cs);
 767         }
 768
 769         pm_runtime_set_active(&pdev->dev);
 770         pm_runtime_use_autosuspend(&pdev->dev);
 771         pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
 772         pm_runtime_enable(&pdev->dev);
 773
 774         status = orion_spi_reset(spi);
 775         if (status < 0)
 776                 goto out_rel_pm;
 777
 778         master->dev.of_node = pdev->dev.of_node;
 779         status = spi_register_master(master);
 780         if (status < 0)
 781                 goto out_rel_pm;
 782
 783         return status;
 784
 785 out_rel_pm:
 786         pm_runtime_disable(&pdev->dev);
 787 out_rel_axi_clk:
 788         clk_disable_unprepare(spi->axi_clk);
 789 out_rel_clk:
 790         clk_disable_unprepare(spi->clk);
 791 out:
 792         spi_master_put(master);
 793         return status;
 794 }
 795
 796
 797 static int orion_spi_remove(struct platform_device *pdev)
 798 {
 799         struct spi_master *master = platform_get_drvdata(pdev);
 800         struct orion_spi *spi = spi_master_get_devdata(master);
 801
 802         pm_runtime_get_sync(&pdev->dev);
 803         clk_disable_unprepare(spi->axi_clk);
 804         clk_disable_unprepare(spi->clk);
 805
 806         spi_unregister_master(master);
 807         pm_runtime_disable(&pdev->dev);
 808
 809         return 0;
 810 }
 811
 812 MODULE_ALIAS("platform:" DRIVER_NAME);
 813
 814 #ifdef CONFIG_PM
 815 static int orion_spi_runtime_suspend(struct device *dev)
 816 {
 817         struct spi_master *master = dev_get_drvdata(dev);
 818         struct orion_spi *spi = spi_master_get_devdata(master);
 819
 820         clk_disable_unprepare(spi->axi_clk);
 821         clk_disable_unprepare(spi->clk);
 822         return 0;
 823 }
 824
 825 static int orion_spi_runtime_resume(struct device *dev)
 826 {
 827         struct spi_master *master = dev_get_drvdata(dev);
 828         struct orion_spi *spi = spi_master_get_devdata(master);
 829
 830         if (!IS_ERR(spi->axi_clk))
 831                 clk_prepare_enable(spi->axi_clk);
 832         return clk_prepare_enable(spi->clk);
 833 }
 834 #endif
 835
 836 static const struct dev_pm_ops orion_spi_pm_ops = {
 837         SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend,
 838                            orion_spi_runtime_resume,
 839                            NULL)
 840 };
 841
 842 static struct platform_driver orion_spi_driver = {
 843         .driver = {
 844                 .name   = DRIVER_NAME,
 845                 .pm     = &orion_spi_pm_ops,
 846                 .of_match_table = of_match_ptr(orion_spi_of_match_table),
 847         },
 848         .probe          = orion_spi_probe,
 849         .remove         = orion_spi_remove,
 850 };
 851
 852 module_platform_driver(orion_spi_driver);
 853
 854 MODULE_DESCRIPTION("Orion SPI driver");
 855 MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>");
 856 MODULE_LICENSE("GPL");