drivers/spi/spi-img-spfi.c

   1 /*
   2  * IMG SPFI controller driver
   3  *
   4  * Copyright (C) 2007,2008,2013 Imagination Technologies Ltd.
   5  * Copyright (C) 2014 Google, Inc.
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms and conditions of the GNU General Public License,
   9  * version 2, as published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/clk.h>
  13 #include <linux/delay.h>
  14 #include <linux/dmaengine.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/io.h>
  17 #include <linux/irq.h>
  18 #include <linux/module.h>
  19 #include <linux/of.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/pm_runtime.h>
  22 #include <linux/scatterlist.h>
  23 #include <linux/slab.h>
  24 #include <linux/spi/spi.h>
  25 #include <linux/spinlock.h>
  26
  27 #define SPFI_DEVICE_PARAMETER(x)                (0x00 + 0x4 * (x))
  28 #define SPFI_DEVICE_PARAMETER_BITCLK_SHIFT      24
  29 #define SPFI_DEVICE_PARAMETER_BITCLK_MASK       0xff
  30 #define SPFI_DEVICE_PARAMETER_CSSETUP_SHIFT     16
  31 #define SPFI_DEVICE_PARAMETER_CSSETUP_MASK      0xff
  32 #define SPFI_DEVICE_PARAMETER_CSHOLD_SHIFT      8
  33 #define SPFI_DEVICE_PARAMETER_CSHOLD_MASK       0xff
  34 #define SPFI_DEVICE_PARAMETER_CSDELAY_SHIFT     0
  35 #define SPFI_DEVICE_PARAMETER_CSDELAY_MASK      0xff
  36
  37 #define SPFI_CONTROL                            0x14
  38 #define SPFI_CONTROL_CONTINUE                   BIT(12)
  39 #define SPFI_CONTROL_SOFT_RESET                 BIT(11)
  40 #define SPFI_CONTROL_SEND_DMA                   BIT(10)
  41 #define SPFI_CONTROL_GET_DMA                    BIT(9)
  42 #define SPFI_CONTROL_TMODE_SHIFT                5
  43 #define SPFI_CONTROL_TMODE_MASK                 0x7
  44 #define SPFI_CONTROL_TMODE_SINGLE               0
  45 #define SPFI_CONTROL_TMODE_DUAL                 1
  46 #define SPFI_CONTROL_TMODE_QUAD                 2
  47 #define SPFI_CONTROL_SPFI_EN                    BIT(0)
  48
  49 #define SPFI_TRANSACTION                        0x18
  50 #define SPFI_TRANSACTION_TSIZE_SHIFT            16
  51 #define SPFI_TRANSACTION_TSIZE_MASK             0xffff
  52
  53 #define SPFI_PORT_STATE                         0x1c
  54 #define SPFI_PORT_STATE_DEV_SEL_SHIFT           20
  55 #define SPFI_PORT_STATE_DEV_SEL_MASK            0x7
  56 #define SPFI_PORT_STATE_CK_POL(x)               BIT(19 - (x))
  57 #define SPFI_PORT_STATE_CK_PHASE(x)             BIT(14 - (x))
  58
  59 #define SPFI_TX_32BIT_VALID_DATA                0x20
  60 #define SPFI_TX_8BIT_VALID_DATA                 0x24
  61 #define SPFI_RX_32BIT_VALID_DATA                0x28
  62 #define SPFI_RX_8BIT_VALID_DATA                 0x2c
  63
  64 #define SPFI_INTERRUPT_STATUS                   0x30
  65 #define SPFI_INTERRUPT_ENABLE                   0x34
  66 #define SPFI_INTERRUPT_CLEAR                    0x38
  67 #define SPFI_INTERRUPT_IACCESS                  BIT(12)
  68 #define SPFI_INTERRUPT_GDEX8BIT                 BIT(11)
  69 #define SPFI_INTERRUPT_ALLDONETRIG              BIT(9)
  70 #define SPFI_INTERRUPT_GDFUL                    BIT(8)
  71 #define SPFI_INTERRUPT_GDHF                     BIT(7)
  72 #define SPFI_INTERRUPT_GDEX32BIT                BIT(6)
  73 #define SPFI_INTERRUPT_GDTRIG                   BIT(5)
  74 #define SPFI_INTERRUPT_SDFUL                    BIT(3)
  75 #define SPFI_INTERRUPT_SDHF                     BIT(2)
  76 #define SPFI_INTERRUPT_SDE                      BIT(1)
  77 #define SPFI_INTERRUPT_SDTRIG                   BIT(0)
  78
  79 /*
  80  * There are four parallel FIFOs of 16 bytes each.  The word buffer
  81  * (*_32BIT_VALID_DATA) accesses all four FIFOs at once, resulting in an
  82  * effective FIFO size of 64 bytes.  The byte buffer (*_8BIT_VALID_DATA)
  83  * accesses only a single FIFO, resulting in an effective FIFO size of
  84  * 16 bytes.
  85  */
  86 #define SPFI_32BIT_FIFO_SIZE                    64
  87 #define SPFI_8BIT_FIFO_SIZE                     16
  88
  89 struct img_spfi {
  90         struct device *dev;
  91         struct spi_master *master;
  92         spinlock_t lock;
  93
  94         void __iomem *regs;
  95         phys_addr_t phys;
  96         int irq;
  97         struct clk *spfi_clk;
  98         struct clk *sys_clk;
  99
 100         struct dma_chan *rx_ch;
 101         struct dma_chan *tx_ch;
 102         bool tx_dma_busy;
 103         bool rx_dma_busy;
 104 };
 105
 106 static inline u32 spfi_readl(struct img_spfi *spfi, u32 reg)
 107 {
 108         return readl(spfi->regs + reg);
 109 }
 110
 111 static inline void spfi_writel(struct img_spfi *spfi, u32 val, u32 reg)
 112 {
 113         writel(val, spfi->regs + reg);
 114 }
 115
 116 static inline void spfi_start(struct img_spfi *spfi)
 117 {
 118         u32 val;
 119
 120         val = spfi_readl(spfi, SPFI_CONTROL);
 121         val |= SPFI_CONTROL_SPFI_EN;
 122         spfi_writel(spfi, val, SPFI_CONTROL);
 123 }
 124
 125 static inline void spfi_stop(struct img_spfi *spfi)
 126 {
 127         u32 val;
 128
 129         val = spfi_readl(spfi, SPFI_CONTROL);
 130         val &= ~SPFI_CONTROL_SPFI_EN;
 131         spfi_writel(spfi, val, SPFI_CONTROL);
 132 }
 133
 134 static inline void spfi_reset(struct img_spfi *spfi)
 135 {
 136         spfi_writel(spfi, SPFI_CONTROL_SOFT_RESET, SPFI_CONTROL);
 137         udelay(1);
 138         spfi_writel(spfi, 0, SPFI_CONTROL);
 139 }
 140
 141 static void spfi_flush_tx_fifo(struct img_spfi *spfi)
 142 {
 143         unsigned long timeout = jiffies + msecs_to_jiffies(10);
 144
 145         spfi_writel(spfi, SPFI_INTERRUPT_SDE, SPFI_INTERRUPT_CLEAR);
 146         while (time_before(jiffies, timeout)) {
 147                 if (spfi_readl(spfi, SPFI_INTERRUPT_STATUS) &
 148                     SPFI_INTERRUPT_SDE)
 149                         return;
 150                 cpu_relax();
 151         }
 152
 153         dev_err(spfi->dev, "Timed out waiting for FIFO to drain\n");
 154         spfi_reset(spfi);
 155 }
 156
 157 static unsigned int spfi_pio_write32(struct img_spfi *spfi, const u32 *buf,
 158                                      unsigned int max)
 159 {
 160         unsigned int count = 0;
 161         u32 status;
 162
 163         while (count < max / 4) {
 164                 spfi_writel(spfi, SPFI_INTERRUPT_SDFUL, SPFI_INTERRUPT_CLEAR);
 165                 status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
 166                 if (status & SPFI_INTERRUPT_SDFUL)
 167                         break;
 168                 spfi_writel(spfi, buf[count], SPFI_TX_32BIT_VALID_DATA);
 169                 count++;
 170         }
 171
 172         return count * 4;
 173 }
 174
 175 static unsigned int spfi_pio_write8(struct img_spfi *spfi, const u8 *buf,
 176                                     unsigned int max)
 177 {
 178         unsigned int count = 0;
 179         u32 status;
 180
 181         while (count < max) {
 182                 spfi_writel(spfi, SPFI_INTERRUPT_SDFUL, SPFI_INTERRUPT_CLEAR);
 183                 status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
 184                 if (status & SPFI_INTERRUPT_SDFUL)
 185                         break;
 186                 spfi_writel(spfi, buf[count], SPFI_TX_8BIT_VALID_DATA);
 187                 count++;
 188         }
 189
 190         return count;
 191 }
 192
 193 static unsigned int spfi_pio_read32(struct img_spfi *spfi, u32 *buf,
 194                                     unsigned int max)
 195 {
 196         unsigned int count = 0;
 197         u32 status;
 198
 199         while (count < max / 4) {
 200                 spfi_writel(spfi, SPFI_INTERRUPT_GDEX32BIT,
 201                             SPFI_INTERRUPT_CLEAR);
 202                 status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
 203                 if (!(status & SPFI_INTERRUPT_GDEX32BIT))
 204                         break;
 205                 buf[count] = spfi_readl(spfi, SPFI_RX_32BIT_VALID_DATA);
 206                 count++;
 207         }
 208
 209         return count * 4;
 210 }
 211
 212 static unsigned int spfi_pio_read8(struct img_spfi *spfi, u8 *buf,
 213                                    unsigned int max)
 214 {
 215         unsigned int count = 0;
 216         u32 status;
 217
 218         while (count < max) {
 219                 spfi_writel(spfi, SPFI_INTERRUPT_GDEX8BIT,
 220                             SPFI_INTERRUPT_CLEAR);
 221                 status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
 222                 if (!(status & SPFI_INTERRUPT_GDEX8BIT))
 223                         break;
 224                 buf[count] = spfi_readl(spfi, SPFI_RX_8BIT_VALID_DATA);
 225                 count++;
 226         }
 227
 228         return count;
 229 }
 230
 231 static int img_spfi_start_pio(struct spi_master *master,
 232                                struct spi_device *spi,
 233                                struct spi_transfer *xfer)
 234 {
 235         struct img_spfi *spfi = spi_master_get_devdata(spi->master);
 236         unsigned int tx_bytes = 0, rx_bytes = 0;
 237         const void *tx_buf = xfer->tx_buf;
 238         void *rx_buf = xfer->rx_buf;
 239         unsigned long timeout;
 240
 241         if (tx_buf)
 242                 tx_bytes = xfer->len;
 243         if (rx_buf)
 244                 rx_bytes = xfer->len;
 245
 246         spfi_start(spfi);
 247
 248         timeout = jiffies +
 249                 msecs_to_jiffies(xfer->len * 8 * 1000 / xfer->speed_hz + 100);
 250         while ((tx_bytes > 0 || rx_bytes > 0) &&
 251                time_before(jiffies, timeout)) {
 252                 unsigned int tx_count, rx_count;
 253
 254                 if (tx_bytes >= 4)
 255                         tx_count = spfi_pio_write32(spfi, tx_buf, tx_bytes);
 256                 else
 257                         tx_count = spfi_pio_write8(spfi, tx_buf, tx_bytes);
 258
 259                 if (rx_bytes >= 4)
 260                         rx_count = spfi_pio_read32(spfi, rx_buf, rx_bytes);
 261                 else
 262                         rx_count = spfi_pio_read8(spfi, rx_buf, rx_bytes);
 263
 264                 tx_buf += tx_count;
 265                 rx_buf += rx_count;
 266                 tx_bytes -= tx_count;
 267                 rx_bytes -= rx_count;
 268
 269                 cpu_relax();
 270         }
 271
 272         if (rx_bytes > 0 || tx_bytes > 0) {
 273                 dev_err(spfi->dev, "PIO transfer timed out\n");
 274                 spfi_reset(spfi);
 275                 return -ETIMEDOUT;
 276         }
 277
 278         if (tx_buf)
 279                 spfi_flush_tx_fifo(spfi);
 280         spfi_stop(spfi);
 281
 282         return 0;
 283 }
 284
 285 static void img_spfi_dma_rx_cb(void *data)
 286 {
 287         struct img_spfi *spfi = data;
 288         unsigned long flags;
 289
 290         spin_lock_irqsave(&spfi->lock, flags);
 291
 292         spfi->rx_dma_busy = false;
 293         if (!spfi->tx_dma_busy) {
 294                 spfi_stop(spfi);
 295                 spi_finalize_current_transfer(spfi->master);
 296         }
 297
 298         spin_unlock_irqrestore(&spfi->lock, flags);
 299 }
 300
 301 static void img_spfi_dma_tx_cb(void *data)
 302 {
 303         struct img_spfi *spfi = data;
 304         unsigned long flags;
 305
 306         spfi_flush_tx_fifo(spfi);
 307
 308         spin_lock_irqsave(&spfi->lock, flags);
 309
 310         spfi->tx_dma_busy = false;
 311         if (!spfi->rx_dma_busy) {
 312                 spfi_stop(spfi);
 313                 spi_finalize_current_transfer(spfi->master);
 314         }
 315
 316         spin_unlock_irqrestore(&spfi->lock, flags);
 317 }
 318
 319 static int img_spfi_start_dma(struct spi_master *master,
 320                               struct spi_device *spi,
 321                               struct spi_transfer *xfer)
 322 {
 323         struct img_spfi *spfi = spi_master_get_devdata(spi->master);
 324         struct dma_async_tx_descriptor *rxdesc = NULL, *txdesc = NULL;
 325         struct dma_slave_config rxconf, txconf;
 326
 327         spfi->rx_dma_busy = false;
 328         spfi->tx_dma_busy = false;
 329
 330         if (xfer->rx_buf) {
 331                 rxconf.direction = DMA_DEV_TO_MEM;
 332                 if (xfer->len % 4 == 0) {
 333                         rxconf.src_addr = spfi->phys + SPFI_RX_32BIT_VALID_DATA;
 334                         rxconf.src_addr_width = 4;
 335                         rxconf.src_maxburst = 4;
 336                 } else {
 337                         rxconf.src_addr = spfi->phys + SPFI_RX_8BIT_VALID_DATA;
 338                         rxconf.src_addr_width = 1;
 339                         rxconf.src_maxburst = 4;
 340                 }
 341                 dmaengine_slave_config(spfi->rx_ch, &rxconf);
 342
 343                 rxdesc = dmaengine_prep_slave_sg(spfi->rx_ch, xfer->rx_sg.sgl,
 344                                                  xfer->rx_sg.nents,
 345                                                  DMA_DEV_TO_MEM,
 346                                                  DMA_PREP_INTERRUPT);
 347                 if (!rxdesc)
 348                         goto stop_dma;
 349
 350                 rxdesc->callback = img_spfi_dma_rx_cb;
 351                 rxdesc->callback_param = spfi;
 352         }
 353
 354         if (xfer->tx_buf) {
 355                 txconf.direction = DMA_MEM_TO_DEV;
 356                 if (xfer->len % 4 == 0) {
 357                         txconf.dst_addr = spfi->phys + SPFI_TX_32BIT_VALID_DATA;
 358                         txconf.dst_addr_width = 4;
 359                         txconf.dst_maxburst = 4;
 360                 } else {
 361                         txconf.dst_addr = spfi->phys + SPFI_TX_8BIT_VALID_DATA;
 362                         txconf.dst_addr_width = 1;
 363                         txconf.dst_maxburst = 4;
 364                 }
 365                 dmaengine_slave_config(spfi->tx_ch, &txconf);
 366
 367                 txdesc = dmaengine_prep_slave_sg(spfi->tx_ch, xfer->tx_sg.sgl,
 368                                                  xfer->tx_sg.nents,
 369                                                  DMA_MEM_TO_DEV,
 370                                                  DMA_PREP_INTERRUPT);
 371                 if (!txdesc)
 372                         goto stop_dma;
 373
 374                 txdesc->callback = img_spfi_dma_tx_cb;
 375                 txdesc->callback_param = spfi;
 376         }
 377
 378         if (xfer->rx_buf) {
 379                 spfi->rx_dma_busy = true;
 380                 dmaengine_submit(rxdesc);
 381                 dma_async_issue_pending(spfi->rx_ch);
 382         }
 383
 384         spfi_start(spfi);
 385
 386         if (xfer->tx_buf) {
 387                 spfi->tx_dma_busy = true;
 388                 dmaengine_submit(txdesc);
 389                 dma_async_issue_pending(spfi->tx_ch);
 390         }
 391
 392         return 1;
 393
 394 stop_dma:
 395         dmaengine_terminate_all(spfi->rx_ch);
 396         dmaengine_terminate_all(spfi->tx_ch);
 397         return -EIO;
 398 }
 399
 400 static void img_spfi_config(struct spi_master *master, struct spi_device *spi,
 401                             struct spi_transfer *xfer)
 402 {
 403         struct img_spfi *spfi = spi_master_get_devdata(spi->master);
 404         u32 val, div;
 405
 406         /*
 407          * output = spfi_clk * (BITCLK / 512), where BITCLK must be a
 408          * power of 2 up to 256 (where 255 == 256 since BITCLK is 8 bits)
 409          */
 410         div = DIV_ROUND_UP(master->max_speed_hz, xfer->speed_hz);
 411         div = clamp(512 / (1 << get_count_order(div)), 1, 255);
 412
 413         val = spfi_readl(spfi, SPFI_DEVICE_PARAMETER(spi->chip_select));
 414         val &= ~(SPFI_DEVICE_PARAMETER_BITCLK_MASK <<
 415                  SPFI_DEVICE_PARAMETER_BITCLK_SHIFT);
 416         val |= div << SPFI_DEVICE_PARAMETER_BITCLK_SHIFT;
 417         spfi_writel(spfi, val, SPFI_DEVICE_PARAMETER(spi->chip_select));
 418
 419         val = spfi_readl(spfi, SPFI_CONTROL);
 420         val &= ~(SPFI_CONTROL_SEND_DMA | SPFI_CONTROL_GET_DMA);
 421         if (xfer->tx_buf)
 422                 val |= SPFI_CONTROL_SEND_DMA;
 423         if (xfer->rx_buf)
 424                 val |= SPFI_CONTROL_GET_DMA;
 425         val &= ~(SPFI_CONTROL_TMODE_MASK << SPFI_CONTROL_TMODE_SHIFT);
 426         if (xfer->tx_nbits == SPI_NBITS_DUAL &&
 427             xfer->rx_nbits == SPI_NBITS_DUAL)
 428                 val |= SPFI_CONTROL_TMODE_DUAL << SPFI_CONTROL_TMODE_SHIFT;
 429         else if (xfer->tx_nbits == SPI_NBITS_QUAD &&
 430                  xfer->rx_nbits == SPI_NBITS_QUAD)
 431                 val |= SPFI_CONTROL_TMODE_QUAD << SPFI_CONTROL_TMODE_SHIFT;
 432         val &= ~SPFI_CONTROL_CONTINUE;
 433         if (!xfer->cs_change && !list_is_last(&xfer->transfer_list,
 434                                               &master->cur_msg->transfers))
 435                 val |= SPFI_CONTROL_CONTINUE;
 436         spfi_writel(spfi, val, SPFI_CONTROL);
 437
 438         val = spfi_readl(spfi, SPFI_PORT_STATE);
 439         if (spi->mode & SPI_CPHA)
 440                 val |= SPFI_PORT_STATE_CK_PHASE(spi->chip_select);
 441         else
 442                 val &= ~SPFI_PORT_STATE_CK_PHASE(spi->chip_select);
 443         if (spi->mode & SPI_CPOL)
 444                 val |= SPFI_PORT_STATE_CK_POL(spi->chip_select);
 445         else
 446                 val &= ~SPFI_PORT_STATE_CK_POL(spi->chip_select);
 447         spfi_writel(spfi, val, SPFI_PORT_STATE);
 448
 449         spfi_writel(spfi, xfer->len << SPFI_TRANSACTION_TSIZE_SHIFT,
 450                     SPFI_TRANSACTION);
 451 }
 452
 453 static int img_spfi_transfer_one(struct spi_master *master,
 454                                  struct spi_device *spi,
 455                                  struct spi_transfer *xfer)
 456 {
 457         struct img_spfi *spfi = spi_master_get_devdata(spi->master);
 458         bool dma_reset = false;
 459         unsigned long flags;
 460         int ret;
 461
 462         /*
 463          * Stop all DMA and reset the controller if the previous transaction
 464          * timed-out and never completed it's DMA.
 465          */
 466         spin_lock_irqsave(&spfi->lock, flags);
 467         if (spfi->tx_dma_busy || spfi->rx_dma_busy) {
 468                 dev_err(spfi->dev, "SPI DMA still busy\n");
 469                 dma_reset = true;
 470         }
 471         spin_unlock_irqrestore(&spfi->lock, flags);
 472
 473         if (dma_reset) {
 474                 dmaengine_terminate_all(spfi->tx_ch);
 475                 dmaengine_terminate_all(spfi->rx_ch);
 476                 spfi_reset(spfi);
 477         }
 478
 479         img_spfi_config(master, spi, xfer);
 480         if (master->can_dma && master->can_dma(master, spi, xfer))
 481                 ret = img_spfi_start_dma(master, spi, xfer);
 482         else
 483                 ret = img_spfi_start_pio(master, spi, xfer);
 484
 485         return ret;
 486 }
 487
 488 static void img_spfi_set_cs(struct spi_device *spi, bool enable)
 489 {
 490         struct img_spfi *spfi = spi_master_get_devdata(spi->master);
 491         u32 val;
 492
 493         val = spfi_readl(spfi, SPFI_PORT_STATE);
 494         val &= ~(SPFI_PORT_STATE_DEV_SEL_MASK << SPFI_PORT_STATE_DEV_SEL_SHIFT);
 495         val |= spi->chip_select << SPFI_PORT_STATE_DEV_SEL_SHIFT;
 496         spfi_writel(spfi, val, SPFI_PORT_STATE);
 497 }
 498
 499 static bool img_spfi_can_dma(struct spi_master *master, struct spi_device *spi,
 500                              struct spi_transfer *xfer)
 501 {
 502         if (xfer->len > SPFI_32BIT_FIFO_SIZE)
 503                 return true;
 504         return false;
 505 }
 506
 507 static irqreturn_t img_spfi_irq(int irq, void *dev_id)
 508 {
 509         struct img_spfi *spfi = (struct img_spfi *)dev_id;
 510         u32 status;
 511
 512         status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
 513         if (status & SPFI_INTERRUPT_IACCESS) {
 514                 spfi_writel(spfi, SPFI_INTERRUPT_IACCESS, SPFI_INTERRUPT_CLEAR);
 515                 dev_err(spfi->dev, "Illegal access interrupt");
 516                 return IRQ_HANDLED;
 517         }
 518
 519         return IRQ_NONE;
 520 }
 521
 522 static int img_spfi_probe(struct platform_device *pdev)
 523 {
 524         struct spi_master *master;
 525         struct img_spfi *spfi;
 526         struct resource *res;
 527         int ret;
 528
 529         master = spi_alloc_master(&pdev->dev, sizeof(*spfi));
 530         if (!master)
 531                 return -ENOMEM;
 532         platform_set_drvdata(pdev, master);
 533
 534         spfi = spi_master_get_devdata(master);
 535         spfi->dev = &pdev->dev;
 536         spfi->master = master;
 537         spin_lock_init(&spfi->lock);
 538
 539         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 540         spfi->regs = devm_ioremap_resource(spfi->dev, res);
 541         if (IS_ERR(spfi->regs)) {
 542                 ret = PTR_ERR(spfi->regs);
 543                 goto put_spi;
 544         }
 545         spfi->phys = res->start;
 546
 547         spfi->irq = platform_get_irq(pdev, 0);
 548         if (spfi->irq < 0) {
 549                 ret = spfi->irq;
 550                 goto put_spi;
 551         }
 552         ret = devm_request_irq(spfi->dev, spfi->irq, img_spfi_irq,
 553                                IRQ_TYPE_LEVEL_HIGH, dev_name(spfi->dev), spfi);
 554         if (ret)
 555                 goto put_spi;
 556
 557         spfi->sys_clk = devm_clk_get(spfi->dev, "sys");
 558         if (IS_ERR(spfi->sys_clk)) {
 559                 ret = PTR_ERR(spfi->sys_clk);
 560                 goto put_spi;
 561         }
 562         spfi->spfi_clk = devm_clk_get(spfi->dev, "spfi");
 563         if (IS_ERR(spfi->spfi_clk)) {
 564                 ret = PTR_ERR(spfi->spfi_clk);
 565                 goto put_spi;
 566         }
 567
 568         ret = clk_prepare_enable(spfi->sys_clk);
 569         if (ret)
 570                 goto put_spi;
 571         ret = clk_prepare_enable(spfi->spfi_clk);
 572         if (ret)
 573                 goto disable_pclk;
 574
 575         spfi_reset(spfi);
 576         /*
 577          * Only enable the error (IACCESS) interrupt.  In PIO mode we'll
 578          * poll the status of the FIFOs.
 579          */
 580         spfi_writel(spfi, SPFI_INTERRUPT_IACCESS, SPFI_INTERRUPT_ENABLE);
 581
 582         master->auto_runtime_pm = true;
 583         master->bus_num = pdev->id;
 584         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_TX_DUAL | SPI_RX_DUAL;
 585         if (of_property_read_bool(spfi->dev->of_node, "img,supports-quad-mode"))
 586                 master->mode_bits |= SPI_TX_QUAD | SPI_RX_QUAD;
 587         master->num_chipselect = 5;
 588         master->dev.of_node = pdev->dev.of_node;
 589         master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(8);
 590         master->max_speed_hz = clk_get_rate(spfi->spfi_clk);
 591         master->min_speed_hz = master->max_speed_hz / 512;
 592
 593         master->set_cs = img_spfi_set_cs;
 594         master->transfer_one = img_spfi_transfer_one;
 595
 596         spfi->tx_ch = dma_request_slave_channel(spfi->dev, "tx");
 597         spfi->rx_ch = dma_request_slave_channel(spfi->dev, "rx");
 598         if (!spfi->tx_ch || !spfi->rx_ch) {
 599                 if (spfi->tx_ch)
 600                         dma_release_channel(spfi->tx_ch);
 601                 if (spfi->rx_ch)
 602                         dma_release_channel(spfi->rx_ch);
 603                 dev_warn(spfi->dev, "Failed to get DMA channels, falling back to PIO mode\n");
 604         } else {
 605                 master->dma_tx = spfi->tx_ch;
 606                 master->dma_rx = spfi->rx_ch;
 607                 master->can_dma = img_spfi_can_dma;
 608         }
 609
 610         pm_runtime_set_active(spfi->dev);
 611         pm_runtime_enable(spfi->dev);
 612
 613         ret = devm_spi_register_master(spfi->dev, master);
 614         if (ret)
 615                 goto disable_pm;
 616
 617         return 0;
 618
 619 disable_pm:
 620         pm_runtime_disable(spfi->dev);
 621         if (spfi->rx_ch)
 622                 dma_release_channel(spfi->rx_ch);
 623         if (spfi->tx_ch)
 624                 dma_release_channel(spfi->tx_ch);
 625         clk_disable_unprepare(spfi->spfi_clk);
 626 disable_pclk:
 627         clk_disable_unprepare(spfi->sys_clk);
 628 put_spi:
 629         spi_master_put(master);
 630
 631         return ret;
 632 }
 633
 634 static int img_spfi_remove(struct platform_device *pdev)
 635 {
 636         struct spi_master *master = platform_get_drvdata(pdev);
 637         struct img_spfi *spfi = spi_master_get_devdata(master);
 638
 639         if (spfi->tx_ch)
 640                 dma_release_channel(spfi->tx_ch);
 641         if (spfi->rx_ch)
 642                 dma_release_channel(spfi->rx_ch);
 643
 644         pm_runtime_disable(spfi->dev);
 645         if (!pm_runtime_status_suspended(spfi->dev)) {
 646                 clk_disable_unprepare(spfi->spfi_clk);
 647                 clk_disable_unprepare(spfi->sys_clk);
 648         }
 649
 650         spi_master_put(master);
 651
 652         return 0;
 653 }
 654
 655 #ifdef CONFIG_PM
 656 static int img_spfi_runtime_suspend(struct device *dev)
 657 {
 658         struct spi_master *master = dev_get_drvdata(dev);
 659         struct img_spfi *spfi = spi_master_get_devdata(master);
 660
 661         clk_disable_unprepare(spfi->spfi_clk);
 662         clk_disable_unprepare(spfi->sys_clk);
 663
 664         return 0;
 665 }
 666
 667 static int img_spfi_runtime_resume(struct device *dev)
 668 {
 669         struct spi_master *master = dev_get_drvdata(dev);
 670         struct img_spfi *spfi = spi_master_get_devdata(master);
 671         int ret;
 672
 673         ret = clk_prepare_enable(spfi->sys_clk);
 674         if (ret)
 675                 return ret;
 676         ret = clk_prepare_enable(spfi->spfi_clk);
 677         if (ret) {
 678                 clk_disable_unprepare(spfi->sys_clk);
 679                 return ret;
 680         }
 681
 682         return 0;
 683 }
 684 #endif /* CONFIG_PM */
 685
 686 #ifdef CONFIG_PM_SLEEP
 687 static int img_spfi_suspend(struct device *dev)
 688 {
 689         struct spi_master *master = dev_get_drvdata(dev);
 690
 691         return spi_master_suspend(master);
 692 }
 693
 694 static int img_spfi_resume(struct device *dev)
 695 {
 696         struct spi_master *master = dev_get_drvdata(dev);
 697         struct img_spfi *spfi = spi_master_get_devdata(master);
 698         int ret;
 699
 700         ret = pm_runtime_get_sync(dev);
 701         if (ret)
 702                 return ret;
 703         spfi_reset(spfi);
 704         pm_runtime_put(dev);
 705
 706         return spi_master_resume(master);
 707 }
 708 #endif /* CONFIG_PM_SLEEP */
 709
 710 static const struct dev_pm_ops img_spfi_pm_ops = {
 711         SET_RUNTIME_PM_OPS(img_spfi_runtime_suspend, img_spfi_runtime_resume,
 712                            NULL)
 713         SET_SYSTEM_SLEEP_PM_OPS(img_spfi_suspend, img_spfi_resume)
 714 };
 715
 716 static const struct of_device_id img_spfi_of_match[] = {
 717         { .compatible = "img,spfi", },
 718         { },
 719 };
 720 MODULE_DEVICE_TABLE(of, img_spfi_of_match);
 721
 722 static struct platform_driver img_spfi_driver = {
 723         .driver = {
 724                 .name = "img-spfi",
 725                 .pm = &img_spfi_pm_ops,
 726                 .of_match_table = of_match_ptr(img_spfi_of_match),
 727         },
 728         .probe = img_spfi_probe,
 729         .remove = img_spfi_remove,
 730 };
 731 module_platform_driver(img_spfi_driver);
 732
 733 MODULE_DESCRIPTION("IMG SPFI controller driver");
 734 MODULE_AUTHOR("Andrew Bresticker <abrestic@chromium.org>");
 735 MODULE_LICENSE("GPL v2");