drivers/spi/spi-sun6i.c

   1 /*
   2  * Copyright (C) 2012 - 2014 Allwinner Tech
   3  * Pan Nan <pannan@allwinnertech.com>
   4  *
   5  * Copyright (C) 2014 Maxime Ripard
   6  * Maxime Ripard <maxime.ripard@free-electrons.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  */
  13
  14 #include <linux/clk.h>
  15 #include <linux/delay.h>
  16 #include <linux/device.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/io.h>
  19 #include <linux/module.h>
  20 #include <linux/of_device.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/pm_runtime.h>
  23 #include <linux/reset.h>
  24
  25 #include <linux/spi/spi.h>
  26
  27 #define SUN6I_FIFO_DEPTH                128
  28 #define SUN8I_FIFO_DEPTH                64
  29
  30 #define SUN6I_GBL_CTL_REG               0x04
  31 #define SUN6I_GBL_CTL_BUS_ENABLE                BIT(0)
  32 #define SUN6I_GBL_CTL_MASTER                    BIT(1)
  33 #define SUN6I_GBL_CTL_TP                        BIT(7)
  34 #define SUN6I_GBL_CTL_RST                       BIT(31)
  35
  36 #define SUN6I_TFR_CTL_REG               0x08
  37 #define SUN6I_TFR_CTL_CPHA                      BIT(0)
  38 #define SUN6I_TFR_CTL_CPOL                      BIT(1)
  39 #define SUN6I_TFR_CTL_SPOL                      BIT(2)
  40 #define SUN6I_TFR_CTL_CS_MASK                   0x30
  41 #define SUN6I_TFR_CTL_CS(cs)                    (((cs) << 4) & SUN6I_TFR_CTL_CS_MASK)
  42 #define SUN6I_TFR_CTL_CS_MANUAL                 BIT(6)
  43 #define SUN6I_TFR_CTL_CS_LEVEL                  BIT(7)
  44 #define SUN6I_TFR_CTL_DHB                       BIT(8)
  45 #define SUN6I_TFR_CTL_FBS                       BIT(12)
  46 #define SUN6I_TFR_CTL_XCH                       BIT(31)
  47
  48 #define SUN6I_INT_CTL_REG               0x10
  49 #define SUN6I_INT_CTL_RF_RDY                    BIT(0)
  50 #define SUN6I_INT_CTL_TF_ERQ                    BIT(4)
  51 #define SUN6I_INT_CTL_RF_OVF                    BIT(8)
  52 #define SUN6I_INT_CTL_TC                        BIT(12)
  53
  54 #define SUN6I_INT_STA_REG               0x14
  55
  56 #define SUN6I_FIFO_CTL_REG              0x18
  57 #define SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_MASK   0xff
  58 #define SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS   0
  59 #define SUN6I_FIFO_CTL_RF_RST                   BIT(15)
  60 #define SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_MASK   0xff
  61 #define SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_BITS   16
  62 #define SUN6I_FIFO_CTL_TF_RST                   BIT(31)
  63
  64 #define SUN6I_FIFO_STA_REG              0x1c
  65 #define SUN6I_FIFO_STA_RF_CNT_MASK              0x7f
  66 #define SUN6I_FIFO_STA_RF_CNT_BITS              0
  67 #define SUN6I_FIFO_STA_TF_CNT_MASK              0x7f
  68 #define SUN6I_FIFO_STA_TF_CNT_BITS              16
  69
  70 #define SUN6I_CLK_CTL_REG               0x24
  71 #define SUN6I_CLK_CTL_CDR2_MASK                 0xff
  72 #define SUN6I_CLK_CTL_CDR2(div)                 (((div) & SUN6I_CLK_CTL_CDR2_MASK) << 0)
  73 #define SUN6I_CLK_CTL_CDR1_MASK                 0xf
  74 #define SUN6I_CLK_CTL_CDR1(div)                 (((div) & SUN6I_CLK_CTL_CDR1_MASK) << 8)
  75 #define SUN6I_CLK_CTL_DRS                       BIT(12)
  76
  77 #define SUN6I_MAX_XFER_SIZE             0xffffff
  78
  79 #define SUN6I_BURST_CNT_REG             0x30
  80 #define SUN6I_BURST_CNT(cnt)                    ((cnt) & SUN6I_MAX_XFER_SIZE)
  81
  82 #define SUN6I_XMIT_CNT_REG              0x34
  83 #define SUN6I_XMIT_CNT(cnt)                     ((cnt) & SUN6I_MAX_XFER_SIZE)
  84
  85 #define SUN6I_BURST_CTL_CNT_REG         0x38
  86 #define SUN6I_BURST_CTL_CNT_STC(cnt)            ((cnt) & SUN6I_MAX_XFER_SIZE)
  87
  88 #define SUN6I_TXDATA_REG                0x200
  89 #define SUN6I_RXDATA_REG                0x300
  90
  91 struct sun6i_spi {
  92         struct spi_master       *master;
  93         void __iomem            *base_addr;
  94         struct clk              *hclk;
  95         struct clk              *mclk;
  96         struct reset_control    *rstc;
  97
  98         struct completion       done;
  99
 100         const u8                *tx_buf;
 101         u8                      *rx_buf;
 102         int                     len;
 103         unsigned long           fifo_depth;
 104 };
 105
 106 static inline u32 sun6i_spi_read(struct sun6i_spi *sspi, u32 reg)
 107 {
 108         return readl(sspi->base_addr + reg);
 109 }
 110
 111 static inline void sun6i_spi_write(struct sun6i_spi *sspi, u32 reg, u32 value)
 112 {
 113         writel(value, sspi->base_addr + reg);
 114 }
 115
 116 static inline u32 sun6i_spi_get_tx_fifo_count(struct sun6i_spi *sspi)
 117 {
 118         u32 reg = sun6i_spi_read(sspi, SUN6I_FIFO_STA_REG);
 119
 120         reg >>= SUN6I_FIFO_STA_TF_CNT_BITS;
 121
 122         return reg & SUN6I_FIFO_STA_TF_CNT_MASK;
 123 }
 124
 125 static inline void sun6i_spi_enable_interrupt(struct sun6i_spi *sspi, u32 mask)
 126 {
 127         u32 reg = sun6i_spi_read(sspi, SUN6I_INT_CTL_REG);
 128
 129         reg |= mask;
 130         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, reg);
 131 }
 132
 133 static inline void sun6i_spi_disable_interrupt(struct sun6i_spi *sspi, u32 mask)
 134 {
 135         u32 reg = sun6i_spi_read(sspi, SUN6I_INT_CTL_REG);
 136
 137         reg &= ~mask;
 138         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, reg);
 139 }
 140
 141 static inline void sun6i_spi_drain_fifo(struct sun6i_spi *sspi, int len)
 142 {
 143         u32 reg, cnt;
 144         u8 byte;
 145
 146         /* See how much data is available */
 147         reg = sun6i_spi_read(sspi, SUN6I_FIFO_STA_REG);
 148         reg &= SUN6I_FIFO_STA_RF_CNT_MASK;
 149         cnt = reg >> SUN6I_FIFO_STA_RF_CNT_BITS;
 150
 151         if (len > cnt)
 152                 len = cnt;
 153
 154         while (len--) {
 155                 byte = readb(sspi->base_addr + SUN6I_RXDATA_REG);
 156                 if (sspi->rx_buf)
 157                         *sspi->rx_buf++ = byte;
 158         }
 159 }
 160
 161 static inline void sun6i_spi_fill_fifo(struct sun6i_spi *sspi, int len)
 162 {
 163         u32 cnt;
 164         u8 byte;
 165
 166         /* See how much data we can fit */
 167         cnt = sspi->fifo_depth - sun6i_spi_get_tx_fifo_count(sspi);
 168
 169         len = min3(len, (int)cnt, sspi->len);
 170
 171         while (len--) {
 172                 byte = sspi->tx_buf ? *sspi->tx_buf++ : 0;
 173                 writeb(byte, sspi->base_addr + SUN6I_TXDATA_REG);
 174                 sspi->len--;
 175         }
 176 }
 177
 178 static void sun6i_spi_set_cs(struct spi_device *spi, bool enable)
 179 {
 180         struct sun6i_spi *sspi = spi_master_get_devdata(spi->master);
 181         u32 reg;
 182
 183         reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
 184         reg &= ~SUN6I_TFR_CTL_CS_MASK;
 185         reg |= SUN6I_TFR_CTL_CS(spi->chip_select);
 186
 187         if (enable)
 188                 reg |= SUN6I_TFR_CTL_CS_LEVEL;
 189         else
 190                 reg &= ~SUN6I_TFR_CTL_CS_LEVEL;
 191
 192         sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg);
 193 }
 194
 195 static size_t sun6i_spi_max_transfer_size(struct spi_device *spi)
 196 {
 197         return SUN6I_MAX_XFER_SIZE - 1;
 198 }
 199
 200 static int sun6i_spi_transfer_one(struct spi_master *master,
 201                                   struct spi_device *spi,
 202                                   struct spi_transfer *tfr)
 203 {
 204         struct sun6i_spi *sspi = spi_master_get_devdata(master);
 205         unsigned int mclk_rate, div, div_cdr1, div_cdr2, timeout;
 206         unsigned int start, end, tx_time;
 207         unsigned int trig_level;
 208         unsigned int tx_len = 0;
 209         int ret = 0;
 210         u32 reg;
 211
 212         if (tfr->len > SUN6I_MAX_XFER_SIZE)
 213                 return -EINVAL;
 214
 215         reinit_completion(&sspi->done);
 216         sspi->tx_buf = tfr->tx_buf;
 217         sspi->rx_buf = tfr->rx_buf;
 218         sspi->len = tfr->len;
 219
 220         /* Clear pending interrupts */
 221         sun6i_spi_write(sspi, SUN6I_INT_STA_REG, ~0);
 222
 223         /* Reset FIFO */
 224         sun6i_spi_write(sspi, SUN6I_FIFO_CTL_REG,
 225                         SUN6I_FIFO_CTL_RF_RST | SUN6I_FIFO_CTL_TF_RST);
 226
 227         /*
 228          * Setup FIFO interrupt trigger level
 229          * Here we choose 3/4 of the full fifo depth, as it's the hardcoded
 230          * value used in old generation of Allwinner SPI controller.
 231          * (See spi-sun4i.c)
 232          */
 233         trig_level = sspi->fifo_depth / 4 * 3;
 234         sun6i_spi_write(sspi, SUN6I_FIFO_CTL_REG,
 235                         (trig_level << SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS) |
 236                         (trig_level << SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_BITS));
 237
 238         /*
 239          * Setup the transfer control register: Chip Select,
 240          * polarities, etc.
 241          */
 242         reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
 243
 244         if (spi->mode & SPI_CPOL)
 245                 reg |= SUN6I_TFR_CTL_CPOL;
 246         else
 247                 reg &= ~SUN6I_TFR_CTL_CPOL;
 248
 249         if (spi->mode & SPI_CPHA)
 250                 reg |= SUN6I_TFR_CTL_CPHA;
 251         else
 252                 reg &= ~SUN6I_TFR_CTL_CPHA;
 253
 254         if (spi->mode & SPI_LSB_FIRST)
 255                 reg |= SUN6I_TFR_CTL_FBS;
 256         else
 257                 reg &= ~SUN6I_TFR_CTL_FBS;
 258
 259         /*
 260          * If it's a TX only transfer, we don't want to fill the RX
 261          * FIFO with bogus data
 262          */
 263         if (sspi->rx_buf)
 264                 reg &= ~SUN6I_TFR_CTL_DHB;
 265         else
 266                 reg |= SUN6I_TFR_CTL_DHB;
 267
 268         /* We want to control the chip select manually */
 269         reg |= SUN6I_TFR_CTL_CS_MANUAL;
 270
 271         sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg);
 272
 273         /* Ensure that we have a parent clock fast enough */
 274         mclk_rate = clk_get_rate(sspi->mclk);
 275         if (mclk_rate < (2 * tfr->speed_hz)) {
 276                 clk_set_rate(sspi->mclk, 2 * tfr->speed_hz);
 277                 mclk_rate = clk_get_rate(sspi->mclk);
 278         }
 279
 280         /*
 281          * Setup clock divider.
 282          *
 283          * We have two choices there. Either we can use the clock
 284          * divide rate 1, which is calculated thanks to this formula:
 285          * SPI_CLK = MOD_CLK / (2 ^ cdr)
 286          * Or we can use CDR2, which is calculated with the formula:
 287          * SPI_CLK = MOD_CLK / (2 * (cdr + 1))
 288          * Wether we use the former or the latter is set through the
 289          * DRS bit.
 290          *
 291          * First try CDR2, and if we can't reach the expected
 292          * frequency, fall back to CDR1.
 293          */
 294         div_cdr1 = DIV_ROUND_UP(mclk_rate, tfr->speed_hz);
 295         div_cdr2 = DIV_ROUND_UP(div_cdr1, 2);
 296         if (div_cdr2 <= (SUN6I_CLK_CTL_CDR2_MASK + 1)) {
 297                 reg = SUN6I_CLK_CTL_CDR2(div_cdr2 - 1) | SUN6I_CLK_CTL_DRS;
 298         } else {
 299                 div = min(SUN6I_CLK_CTL_CDR1_MASK, order_base_2(div_cdr1));
 300                 reg = SUN6I_CLK_CTL_CDR1(div);
 301         }
 302
 303         sun6i_spi_write(sspi, SUN6I_CLK_CTL_REG, reg);
 304         /* Finally enable the bus - doing so before might raise SCK to HIGH */
 305         reg = sun6i_spi_read(sspi, SUN6I_GBL_CTL_REG);
 306         reg |= SUN6I_GBL_CTL_BUS_ENABLE;
 307         sun6i_spi_write(sspi, SUN6I_GBL_CTL_REG, reg);
 308
 309         /* Setup the transfer now... */
 310         if (sspi->tx_buf)
 311                 tx_len = tfr->len;
 312
 313         /* Setup the counters */
 314         sun6i_spi_write(sspi, SUN6I_BURST_CNT_REG, SUN6I_BURST_CNT(tfr->len));
 315         sun6i_spi_write(sspi, SUN6I_XMIT_CNT_REG, SUN6I_XMIT_CNT(tx_len));
 316         sun6i_spi_write(sspi, SUN6I_BURST_CTL_CNT_REG,
 317                         SUN6I_BURST_CTL_CNT_STC(tx_len));
 318
 319         /* Fill the TX FIFO */
 320         sun6i_spi_fill_fifo(sspi, sspi->fifo_depth);
 321
 322         /* Enable the interrupts */
 323         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, SUN6I_INT_CTL_TC);
 324         sun6i_spi_enable_interrupt(sspi, SUN6I_INT_CTL_TC |
 325                                          SUN6I_INT_CTL_RF_RDY);
 326         if (tx_len > sspi->fifo_depth)
 327                 sun6i_spi_enable_interrupt(sspi, SUN6I_INT_CTL_TF_ERQ);
 328
 329         /* Start the transfer */
 330         reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
 331         sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg | SUN6I_TFR_CTL_XCH);
 332
 333         tx_time = max(tfr->len * 8 * 2 / (tfr->speed_hz / 1000), 100U);
 334         start = jiffies;
 335         timeout = wait_for_completion_timeout(&sspi->done,
 336                                               msecs_to_jiffies(tx_time));
 337         end = jiffies;
 338         if (!timeout) {
 339                 dev_warn(&master->dev,
 340                          "%s: timeout transferring %u bytes@%iHz for %i(%i)ms",
 341                          dev_name(&spi->dev), tfr->len, tfr->speed_hz,
 342                          jiffies_to_msecs(end - start), tx_time);
 343                 ret = -ETIMEDOUT;
 344                 goto out;
 345         }
 346
 347 out:
 348         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, 0);
 349
 350         return ret;
 351 }
 352
 353 static irqreturn_t sun6i_spi_handler(int irq, void *dev_id)
 354 {
 355         struct sun6i_spi *sspi = dev_id;
 356         u32 status = sun6i_spi_read(sspi, SUN6I_INT_STA_REG);
 357
 358         /* Transfer complete */
 359         if (status & SUN6I_INT_CTL_TC) {
 360                 sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TC);
 361                 sun6i_spi_drain_fifo(sspi, sspi->fifo_depth);
 362                 complete(&sspi->done);
 363                 return IRQ_HANDLED;
 364         }
 365
 366         /* Receive FIFO 3/4 full */
 367         if (status & SUN6I_INT_CTL_RF_RDY) {
 368                 sun6i_spi_drain_fifo(sspi, SUN6I_FIFO_DEPTH);
 369                 /* Only clear the interrupt _after_ draining the FIFO */
 370                 sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_RF_RDY);
 371                 return IRQ_HANDLED;
 372         }
 373
 374         /* Transmit FIFO 3/4 empty */
 375         if (status & SUN6I_INT_CTL_TF_ERQ) {
 376                 sun6i_spi_fill_fifo(sspi, SUN6I_FIFO_DEPTH);
 377
 378                 if (!sspi->len)
 379                         /* nothing left to transmit */
 380                         sun6i_spi_disable_interrupt(sspi, SUN6I_INT_CTL_TF_ERQ);
 381
 382                 /* Only clear the interrupt _after_ re-seeding the FIFO */
 383                 sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TF_ERQ);
 384
 385                 return IRQ_HANDLED;
 386         }
 387
 388         return IRQ_NONE;
 389 }
 390
 391 static int sun6i_spi_runtime_resume(struct device *dev)
 392 {
 393         struct spi_master *master = dev_get_drvdata(dev);
 394         struct sun6i_spi *sspi = spi_master_get_devdata(master);
 395         int ret;
 396
 397         ret = clk_prepare_enable(sspi->hclk);
 398         if (ret) {
 399                 dev_err(dev, "Couldn't enable AHB clock\n");
 400                 goto out;
 401         }
 402
 403         ret = clk_prepare_enable(sspi->mclk);
 404         if (ret) {
 405                 dev_err(dev, "Couldn't enable module clock\n");
 406                 goto err;
 407         }
 408
 409         ret = reset_control_deassert(sspi->rstc);
 410         if (ret) {
 411                 dev_err(dev, "Couldn't deassert the device from reset\n");
 412                 goto err2;
 413         }
 414
 415         sun6i_spi_write(sspi, SUN6I_GBL_CTL_REG,
 416                         SUN6I_GBL_CTL_MASTER | SUN6I_GBL_CTL_TP);
 417
 418         return 0;
 419
 420 err2:
 421         clk_disable_unprepare(sspi->mclk);
 422 err:
 423         clk_disable_unprepare(sspi->hclk);
 424 out:
 425         return ret;
 426 }
 427
 428 static int sun6i_spi_runtime_suspend(struct device *dev)
 429 {
 430         struct spi_master *master = dev_get_drvdata(dev);
 431         struct sun6i_spi *sspi = spi_master_get_devdata(master);
 432
 433         reset_control_assert(sspi->rstc);
 434         clk_disable_unprepare(sspi->mclk);
 435         clk_disable_unprepare(sspi->hclk);
 436
 437         return 0;
 438 }
 439
 440 static int sun6i_spi_probe(struct platform_device *pdev)
 441 {
 442         struct spi_master *master;
 443         struct sun6i_spi *sspi;
 444         struct resource *res;
 445         int ret = 0, irq;
 446
 447         master = spi_alloc_master(&pdev->dev, sizeof(struct sun6i_spi));
 448         if (!master) {
 449                 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
 450                 return -ENOMEM;
 451         }
 452
 453         platform_set_drvdata(pdev, master);
 454         sspi = spi_master_get_devdata(master);
 455
 456         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 457         sspi->base_addr = devm_ioremap_resource(&pdev->dev, res);
 458         if (IS_ERR(sspi->base_addr)) {
 459                 ret = PTR_ERR(sspi->base_addr);
 460                 goto err_free_master;
 461         }
 462
 463         irq = platform_get_irq(pdev, 0);
 464         if (irq < 0) {
 465                 dev_err(&pdev->dev, "No spi IRQ specified\n");
 466                 ret = -ENXIO;
 467                 goto err_free_master;
 468         }
 469
 470         ret = devm_request_irq(&pdev->dev, irq, sun6i_spi_handler,
 471                                0, "sun6i-spi", sspi);
 472         if (ret) {
 473                 dev_err(&pdev->dev, "Cannot request IRQ\n");
 474                 goto err_free_master;
 475         }
 476
 477         sspi->master = master;
 478         sspi->fifo_depth = (unsigned long)of_device_get_match_data(&pdev->dev);
 479
 480         master->max_speed_hz = 100 * 1000 * 1000;
 481         master->min_speed_hz = 3 * 1000;
 482         master->set_cs = sun6i_spi_set_cs;
 483         master->transfer_one = sun6i_spi_transfer_one;
 484         master->num_chipselect = 4;
 485         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
 486         master->bits_per_word_mask = SPI_BPW_MASK(8);
 487         master->dev.of_node = pdev->dev.of_node;
 488         master->auto_runtime_pm = true;
 489         master->max_transfer_size = sun6i_spi_max_transfer_size;
 490
 491         sspi->hclk = devm_clk_get(&pdev->dev, "ahb");
 492         if (IS_ERR(sspi->hclk)) {
 493                 dev_err(&pdev->dev, "Unable to acquire AHB clock\n");
 494                 ret = PTR_ERR(sspi->hclk);
 495                 goto err_free_master;
 496         }
 497
 498         sspi->mclk = devm_clk_get(&pdev->dev, "mod");
 499         if (IS_ERR(sspi->mclk)) {
 500                 dev_err(&pdev->dev, "Unable to acquire module clock\n");
 501                 ret = PTR_ERR(sspi->mclk);
 502                 goto err_free_master;
 503         }
 504
 505         init_completion(&sspi->done);
 506
 507         sspi->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
 508         if (IS_ERR(sspi->rstc)) {
 509                 dev_err(&pdev->dev, "Couldn't get reset controller\n");
 510                 ret = PTR_ERR(sspi->rstc);
 511                 goto err_free_master;
 512         }
 513
 514         /*
 515          * This wake-up/shutdown pattern is to be able to have the
 516          * device woken up, even if runtime_pm is disabled
 517          */
 518         ret = sun6i_spi_runtime_resume(&pdev->dev);
 519         if (ret) {
 520                 dev_err(&pdev->dev, "Couldn't resume the device\n");
 521                 goto err_free_master;
 522         }
 523
 524         pm_runtime_set_active(&pdev->dev);
 525         pm_runtime_enable(&pdev->dev);
 526         pm_runtime_idle(&pdev->dev);
 527
 528         ret = devm_spi_register_master(&pdev->dev, master);
 529         if (ret) {
 530                 dev_err(&pdev->dev, "cannot register SPI master\n");
 531                 goto err_pm_disable;
 532         }
 533
 534         return 0;
 535
 536 err_pm_disable:
 537         pm_runtime_disable(&pdev->dev);
 538         sun6i_spi_runtime_suspend(&pdev->dev);
 539 err_free_master:
 540         spi_master_put(master);
 541         return ret;
 542 }
 543
 544 static int sun6i_spi_remove(struct platform_device *pdev)
 545 {
 546         pm_runtime_force_suspend(&pdev->dev);
 547
 548         return 0;
 549 }
 550
 551 static const struct of_device_id sun6i_spi_match[] = {
 552         { .compatible = "allwinner,sun6i-a31-spi", .data = (void *)SUN6I_FIFO_DEPTH },
 553         { .compatible = "allwinner,sun8i-h3-spi",  .data = (void *)SUN8I_FIFO_DEPTH },
 554         {}
 555 };
 556 MODULE_DEVICE_TABLE(of, sun6i_spi_match);
 557
 558 static const struct dev_pm_ops sun6i_spi_pm_ops = {
 559         .runtime_resume         = sun6i_spi_runtime_resume,
 560         .runtime_suspend        = sun6i_spi_runtime_suspend,
 561 };
 562
 563 static struct platform_driver sun6i_spi_driver = {
 564         .probe  = sun6i_spi_probe,
 565         .remove = sun6i_spi_remove,
 566         .driver = {
 567                 .name           = "sun6i-spi",
 568                 .of_match_table = sun6i_spi_match,
 569                 .pm             = &sun6i_spi_pm_ops,
 570         },
 571 };
 572 module_platform_driver(sun6i_spi_driver);
 573
 574 MODULE_AUTHOR("Pan Nan <pannan@allwinnertech.com>");
 575 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
 576 MODULE_DESCRIPTION("Allwinner A31 SPI controller driver");
 577 MODULE_LICENSE("GPL");