drivers/spi/spi-s3c64xx.c

   1 /*
   2  * Copyright (C) 2009 Samsung Electronics Ltd.
   3  *      Jaswinder Singh <jassi.brar@samsung.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19
  20 #include <linux/init.h>
  21 #include <linux/module.h>
  22 #include <linux/workqueue.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/delay.h>
  25 #include <linux/clk.h>
  26 #include <linux/dma-mapping.h>
  27 #include <linux/dmaengine.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/pm_runtime.h>
  30 #include <linux/spi/spi.h>
  31 #include <linux/gpio.h>
  32 #include <linux/of.h>
  33 #include <linux/of_gpio.h>
  34
  35 #include <linux/platform_data/spi-s3c64xx.h>
  36
  37 #define MAX_SPI_PORTS           3
  38 #define S3C64XX_SPI_QUIRK_POLL          (1 << 0)
  39
  40 /* Registers and bit-fields */
  41
  42 #define S3C64XX_SPI_CH_CFG              0x00
  43 #define S3C64XX_SPI_CLK_CFG             0x04
  44 #define S3C64XX_SPI_MODE_CFG    0x08
  45 #define S3C64XX_SPI_SLAVE_SEL   0x0C
  46 #define S3C64XX_SPI_INT_EN              0x10
  47 #define S3C64XX_SPI_STATUS              0x14
  48 #define S3C64XX_SPI_TX_DATA             0x18
  49 #define S3C64XX_SPI_RX_DATA             0x1C
  50 #define S3C64XX_SPI_PACKET_CNT  0x20
  51 #define S3C64XX_SPI_PENDING_CLR 0x24
  52 #define S3C64XX_SPI_SWAP_CFG    0x28
  53 #define S3C64XX_SPI_FB_CLK              0x2C
  54
  55 #define S3C64XX_SPI_CH_HS_EN            (1<<6)  /* High Speed Enable */
  56 #define S3C64XX_SPI_CH_SW_RST           (1<<5)
  57 #define S3C64XX_SPI_CH_SLAVE            (1<<4)
  58 #define S3C64XX_SPI_CPOL_L              (1<<3)
  59 #define S3C64XX_SPI_CPHA_B              (1<<2)
  60 #define S3C64XX_SPI_CH_RXCH_ON          (1<<1)
  61 #define S3C64XX_SPI_CH_TXCH_ON          (1<<0)
  62
  63 #define S3C64XX_SPI_CLKSEL_SRCMSK       (3<<9)
  64 #define S3C64XX_SPI_CLKSEL_SRCSHFT      9
  65 #define S3C64XX_SPI_ENCLK_ENABLE        (1<<8)
  66 #define S3C64XX_SPI_PSR_MASK            0xff
  67
  68 #define S3C64XX_SPI_MODE_CH_TSZ_BYTE            (0<<29)
  69 #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD        (1<<29)
  70 #define S3C64XX_SPI_MODE_CH_TSZ_WORD            (2<<29)
  71 #define S3C64XX_SPI_MODE_CH_TSZ_MASK            (3<<29)
  72 #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE           (0<<17)
  73 #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD       (1<<17)
  74 #define S3C64XX_SPI_MODE_BUS_TSZ_WORD           (2<<17)
  75 #define S3C64XX_SPI_MODE_BUS_TSZ_MASK           (3<<17)
  76 #define S3C64XX_SPI_MODE_RXDMA_ON               (1<<2)
  77 #define S3C64XX_SPI_MODE_TXDMA_ON               (1<<1)
  78 #define S3C64XX_SPI_MODE_4BURST                 (1<<0)
  79
  80 #define S3C64XX_SPI_SLAVE_AUTO                  (1<<1)
  81 #define S3C64XX_SPI_SLAVE_SIG_INACT             (1<<0)
  82
  83 #define S3C64XX_SPI_INT_TRAILING_EN             (1<<6)
  84 #define S3C64XX_SPI_INT_RX_OVERRUN_EN           (1<<5)
  85 #define S3C64XX_SPI_INT_RX_UNDERRUN_EN          (1<<4)
  86 #define S3C64XX_SPI_INT_TX_OVERRUN_EN           (1<<3)
  87 #define S3C64XX_SPI_INT_TX_UNDERRUN_EN          (1<<2)
  88 #define S3C64XX_SPI_INT_RX_FIFORDY_EN           (1<<1)
  89 #define S3C64XX_SPI_INT_TX_FIFORDY_EN           (1<<0)
  90
  91 #define S3C64XX_SPI_ST_RX_OVERRUN_ERR           (1<<5)
  92 #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR  (1<<4)
  93 #define S3C64XX_SPI_ST_TX_OVERRUN_ERR           (1<<3)
  94 #define S3C64XX_SPI_ST_TX_UNDERRUN_ERR  (1<<2)
  95 #define S3C64XX_SPI_ST_RX_FIFORDY               (1<<1)
  96 #define S3C64XX_SPI_ST_TX_FIFORDY               (1<<0)
  97
  98 #define S3C64XX_SPI_PACKET_CNT_EN               (1<<16)
  99
 100 #define S3C64XX_SPI_PND_TX_UNDERRUN_CLR         (1<<4)
 101 #define S3C64XX_SPI_PND_TX_OVERRUN_CLR          (1<<3)
 102 #define S3C64XX_SPI_PND_RX_UNDERRUN_CLR         (1<<2)
 103 #define S3C64XX_SPI_PND_RX_OVERRUN_CLR          (1<<1)
 104 #define S3C64XX_SPI_PND_TRAILING_CLR            (1<<0)
 105
 106 #define S3C64XX_SPI_SWAP_RX_HALF_WORD           (1<<7)
 107 #define S3C64XX_SPI_SWAP_RX_BYTE                (1<<6)
 108 #define S3C64XX_SPI_SWAP_RX_BIT                 (1<<5)
 109 #define S3C64XX_SPI_SWAP_RX_EN                  (1<<4)
 110 #define S3C64XX_SPI_SWAP_TX_HALF_WORD           (1<<3)
 111 #define S3C64XX_SPI_SWAP_TX_BYTE                (1<<2)
 112 #define S3C64XX_SPI_SWAP_TX_BIT                 (1<<1)
 113 #define S3C64XX_SPI_SWAP_TX_EN                  (1<<0)
 114
 115 #define S3C64XX_SPI_FBCLK_MSK           (3<<0)
 116
 117 #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
 118 #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
 119                                 (1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
 120 #define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
 121 #define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
 122                                         FIFO_LVL_MASK(i))
 123
 124 #define S3C64XX_SPI_MAX_TRAILCNT        0x3ff
 125 #define S3C64XX_SPI_TRAILCNT_OFF        19
 126
 127 #define S3C64XX_SPI_TRAILCNT            S3C64XX_SPI_MAX_TRAILCNT
 128
 129 #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
 130 #define is_polling(x)   (x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
 131
 132 #define RXBUSY    (1<<2)
 133 #define TXBUSY    (1<<3)
 134
 135 struct s3c64xx_spi_dma_data {
 136         struct dma_chan *ch;
 137         enum dma_transfer_direction direction;
 138         unsigned int dmach;
 139 };
 140
 141 /**
 142  * struct s3c64xx_spi_info - SPI Controller hardware info
 143  * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
 144  * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
 145  * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
 146  * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
 147  * @clk_from_cmu: True, if the controller does not include a clock mux and
 148  *      prescaler unit.
 149  *
 150  * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
 151  * differ in some aspects such as the size of the fifo and spi bus clock
 152  * setup. Such differences are specified to the driver using this structure
 153  * which is provided as driver data to the driver.
 154  */
 155 struct s3c64xx_spi_port_config {
 156         int     fifo_lvl_mask[MAX_SPI_PORTS];
 157         int     rx_lvl_offset;
 158         int     tx_st_done;
 159         int     quirks;
 160         bool    high_speed;
 161         bool    clk_from_cmu;
 162 };
 163
 164 /**
 165  * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
 166  * @clk: Pointer to the spi clock.
 167  * @src_clk: Pointer to the clock used to generate SPI signals.
 168  * @master: Pointer to the SPI Protocol master.
 169  * @cntrlr_info: Platform specific data for the controller this driver manages.
 170  * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint.
 171  * @lock: Controller specific lock.
 172  * @state: Set of FLAGS to indicate status.
 173  * @rx_dmach: Controller's DMA channel for Rx.
 174  * @tx_dmach: Controller's DMA channel for Tx.
 175  * @sfr_start: BUS address of SPI controller regs.
 176  * @regs: Pointer to ioremap'ed controller registers.
 177  * @irq: interrupt
 178  * @xfer_completion: To indicate completion of xfer task.
 179  * @cur_mode: Stores the active configuration of the controller.
 180  * @cur_bpw: Stores the active bits per word settings.
 181  * @cur_speed: Stores the active xfer clock speed.
 182  */
 183 struct s3c64xx_spi_driver_data {
 184         void __iomem                    *regs;
 185         struct clk                      *clk;
 186         struct clk                      *src_clk;
 187         struct platform_device          *pdev;
 188         struct spi_master               *master;
 189         struct s3c64xx_spi_info  *cntrlr_info;
 190         struct spi_device               *tgl_spi;
 191         spinlock_t                      lock;
 192         unsigned long                   sfr_start;
 193         struct completion               xfer_completion;
 194         unsigned                        state;
 195         unsigned                        cur_mode, cur_bpw;
 196         unsigned                        cur_speed;
 197         struct s3c64xx_spi_dma_data     rx_dma;
 198         struct s3c64xx_spi_dma_data     tx_dma;
 199         struct s3c64xx_spi_port_config  *port_conf;
 200         unsigned int                    port_id;
 201         bool                            cs_gpio;
 202 };
 203
 204 static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
 205 {
 206         void __iomem *regs = sdd->regs;
 207         unsigned long loops;
 208         u32 val;
 209
 210         writel(0, regs + S3C64XX_SPI_PACKET_CNT);
 211
 212         val = readl(regs + S3C64XX_SPI_CH_CFG);
 213         val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
 214         writel(val, regs + S3C64XX_SPI_CH_CFG);
 215
 216         val = readl(regs + S3C64XX_SPI_CH_CFG);
 217         val |= S3C64XX_SPI_CH_SW_RST;
 218         val &= ~S3C64XX_SPI_CH_HS_EN;
 219         writel(val, regs + S3C64XX_SPI_CH_CFG);
 220
 221         /* Flush TxFIFO*/
 222         loops = msecs_to_loops(1);
 223         do {
 224                 val = readl(regs + S3C64XX_SPI_STATUS);
 225         } while (TX_FIFO_LVL(val, sdd) && loops--);
 226
 227         if (loops == 0)
 228                 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
 229
 230         /* Flush RxFIFO*/
 231         loops = msecs_to_loops(1);
 232         do {
 233                 val = readl(regs + S3C64XX_SPI_STATUS);
 234                 if (RX_FIFO_LVL(val, sdd))
 235                         readl(regs + S3C64XX_SPI_RX_DATA);
 236                 else
 237                         break;
 238         } while (loops--);
 239
 240         if (loops == 0)
 241                 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
 242
 243         val = readl(regs + S3C64XX_SPI_CH_CFG);
 244         val &= ~S3C64XX_SPI_CH_SW_RST;
 245         writel(val, regs + S3C64XX_SPI_CH_CFG);
 246
 247         val = readl(regs + S3C64XX_SPI_MODE_CFG);
 248         val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
 249         writel(val, regs + S3C64XX_SPI_MODE_CFG);
 250 }
 251
 252 static void s3c64xx_spi_dmacb(void *data)
 253 {
 254         struct s3c64xx_spi_driver_data *sdd;
 255         struct s3c64xx_spi_dma_data *dma = data;
 256         unsigned long flags;
 257
 258         if (dma->direction == DMA_DEV_TO_MEM)
 259                 sdd = container_of(data,
 260                         struct s3c64xx_spi_driver_data, rx_dma);
 261         else
 262                 sdd = container_of(data,
 263                         struct s3c64xx_spi_driver_data, tx_dma);
 264
 265         spin_lock_irqsave(&sdd->lock, flags);
 266
 267         if (dma->direction == DMA_DEV_TO_MEM) {
 268                 sdd->state &= ~RXBUSY;
 269                 if (!(sdd->state & TXBUSY))
 270                         complete(&sdd->xfer_completion);
 271         } else {
 272                 sdd->state &= ~TXBUSY;
 273                 if (!(sdd->state & RXBUSY))
 274                         complete(&sdd->xfer_completion);
 275         }
 276
 277         spin_unlock_irqrestore(&sdd->lock, flags);
 278 }
 279
 280 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
 281                         struct sg_table *sgt)
 282 {
 283         struct s3c64xx_spi_driver_data *sdd;
 284         struct dma_slave_config config;
 285         struct dma_async_tx_descriptor *desc;
 286
 287         memset(&config, 0, sizeof(config));
 288
 289         if (dma->direction == DMA_DEV_TO_MEM) {
 290                 sdd = container_of((void *)dma,
 291                         struct s3c64xx_spi_driver_data, rx_dma);
 292                 config.direction = dma->direction;
 293                 config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
 294                 config.src_addr_width = sdd->cur_bpw / 8;
 295                 config.src_maxburst = 1;
 296                 dmaengine_slave_config(dma->ch, &config);
 297         } else {
 298                 sdd = container_of((void *)dma,
 299                         struct s3c64xx_spi_driver_data, tx_dma);
 300                 config.direction = dma->direction;
 301                 config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
 302                 config.dst_addr_width = sdd->cur_bpw / 8;
 303                 config.dst_maxburst = 1;
 304                 dmaengine_slave_config(dma->ch, &config);
 305         }
 306
 307         desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
 308                                        dma->direction, DMA_PREP_INTERRUPT);
 309
 310         desc->callback = s3c64xx_spi_dmacb;
 311         desc->callback_param = dma;
 312
 313         dmaengine_submit(desc);
 314         dma_async_issue_pending(dma->ch);
 315 }
 316
 317 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
 318 {
 319         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
 320         dma_filter_fn filter = sdd->cntrlr_info->filter;
 321         struct device *dev = &sdd->pdev->dev;
 322         dma_cap_mask_t mask;
 323         int ret;
 324
 325         if (!is_polling(sdd)) {
 326                 dma_cap_zero(mask);
 327                 dma_cap_set(DMA_SLAVE, mask);
 328
 329                 /* Acquire DMA channels */
 330                 sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter,
 331                                    (void *)sdd->rx_dma.dmach, dev, "rx");
 332                 if (!sdd->rx_dma.ch) {
 333                         dev_err(dev, "Failed to get RX DMA channel\n");
 334                         ret = -EBUSY;
 335                         goto out;
 336                 }
 337                 spi->dma_rx = sdd->rx_dma.ch;
 338
 339                 sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter,
 340                                    (void *)sdd->tx_dma.dmach, dev, "tx");
 341                 if (!sdd->tx_dma.ch) {
 342                         dev_err(dev, "Failed to get TX DMA channel\n");
 343                         ret = -EBUSY;
 344                         goto out_rx;
 345                 }
 346                 spi->dma_tx = sdd->tx_dma.ch;
 347         }
 348
 349         ret = pm_runtime_get_sync(&sdd->pdev->dev);
 350         if (ret < 0) {
 351                 dev_err(dev, "Failed to enable device: %d\n", ret);
 352                 goto out_tx;
 353         }
 354
 355         return 0;
 356
 357 out_tx:
 358         dma_release_channel(sdd->tx_dma.ch);
 359 out_rx:
 360         dma_release_channel(sdd->rx_dma.ch);
 361 out:
 362         return ret;
 363 }
 364
 365 static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
 366 {
 367         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
 368
 369         /* Free DMA channels */
 370         if (!is_polling(sdd)) {
 371                 dma_release_channel(sdd->rx_dma.ch);
 372                 dma_release_channel(sdd->tx_dma.ch);
 373         }
 374
 375         pm_runtime_put(&sdd->pdev->dev);
 376         return 0;
 377 }
 378
 379 static bool s3c64xx_spi_can_dma(struct spi_master *master,
 380                                 struct spi_device *spi,
 381                                 struct spi_transfer *xfer)
 382 {
 383         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
 384
 385         return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
 386 }
 387
 388 static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
 389                                 struct spi_device *spi,
 390                                 struct spi_transfer *xfer, int dma_mode)
 391 {
 392         void __iomem *regs = sdd->regs;
 393         u32 modecfg, chcfg;
 394
 395         modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
 396         modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
 397
 398         chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
 399         chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
 400
 401         if (dma_mode) {
 402                 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
 403         } else {
 404                 /* Always shift in data in FIFO, even if xfer is Tx only,
 405                  * this helps setting PCKT_CNT value for generating clocks
 406                  * as exactly needed.
 407                  */
 408                 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
 409                 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
 410                                         | S3C64XX_SPI_PACKET_CNT_EN,
 411                                         regs + S3C64XX_SPI_PACKET_CNT);
 412         }
 413
 414         if (xfer->tx_buf != NULL) {
 415                 sdd->state |= TXBUSY;
 416                 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
 417                 if (dma_mode) {
 418                         modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
 419                         prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
 420                 } else {
 421                         switch (sdd->cur_bpw) {
 422                         case 32:
 423                                 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
 424                                         xfer->tx_buf, xfer->len / 4);
 425                                 break;
 426                         case 16:
 427                                 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
 428                                         xfer->tx_buf, xfer->len / 2);
 429                                 break;
 430                         default:
 431                                 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
 432                                         xfer->tx_buf, xfer->len);
 433                                 break;
 434                         }
 435                 }
 436         }
 437
 438         if (xfer->rx_buf != NULL) {
 439                 sdd->state |= RXBUSY;
 440
 441                 if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
 442                                         && !(sdd->cur_mode & SPI_CPHA))
 443                         chcfg |= S3C64XX_SPI_CH_HS_EN;
 444
 445                 if (dma_mode) {
 446                         modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
 447                         chcfg |= S3C64XX_SPI_CH_RXCH_ON;
 448                         writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
 449                                         | S3C64XX_SPI_PACKET_CNT_EN,
 450                                         regs + S3C64XX_SPI_PACKET_CNT);
 451                         prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
 452                 }
 453         }
 454
 455         writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
 456         writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
 457 }
 458
 459 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
 460                                         int timeout_ms)
 461 {
 462         void __iomem *regs = sdd->regs;
 463         unsigned long val = 1;
 464         u32 status;
 465
 466         /* max fifo depth available */
 467         u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
 468
 469         if (timeout_ms)
 470                 val = msecs_to_loops(timeout_ms);
 471
 472         do {
 473                 status = readl(regs + S3C64XX_SPI_STATUS);
 474         } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
 475
 476         /* return the actual received data length */
 477         return RX_FIFO_LVL(status, sdd);
 478 }
 479
 480 static int wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
 481                         struct spi_transfer *xfer)
 482 {
 483         void __iomem *regs = sdd->regs;
 484         unsigned long val;
 485         u32 status;
 486         int ms;
 487
 488         /* millisecs to xfer 'len' bytes @ 'cur_speed' */
 489         ms = xfer->len * 8 * 1000 / sdd->cur_speed;
 490         ms += 10; /* some tolerance */
 491
 492         val = msecs_to_jiffies(ms) + 10;
 493         val = wait_for_completion_timeout(&sdd->xfer_completion, val);
 494
 495         /*
 496          * If the previous xfer was completed within timeout, then
 497          * proceed further else return -EIO.
 498          * DmaTx returns after simply writing data in the FIFO,
 499          * w/o waiting for real transmission on the bus to finish.
 500          * DmaRx returns only after Dma read data from FIFO which
 501          * needs bus transmission to finish, so we don't worry if
 502          * Xfer involved Rx(with or without Tx).
 503          */
 504         if (val && !xfer->rx_buf) {
 505                 val = msecs_to_loops(10);
 506                 status = readl(regs + S3C64XX_SPI_STATUS);
 507                 while ((TX_FIFO_LVL(status, sdd)
 508                         || !S3C64XX_SPI_ST_TX_DONE(status, sdd))
 509                        && --val) {
 510                         cpu_relax();
 511                         status = readl(regs + S3C64XX_SPI_STATUS);
 512                 }
 513
 514         }
 515
 516         /* If timed out while checking rx/tx status return error */
 517         if (!val)
 518                 return -EIO;
 519
 520         return 0;
 521 }
 522
 523 static int wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
 524                         struct spi_transfer *xfer)
 525 {
 526         void __iomem *regs = sdd->regs;
 527         unsigned long val;
 528         u32 status;
 529         int loops;
 530         u32 cpy_len;
 531         u8 *buf;
 532         int ms;
 533
 534         /* millisecs to xfer 'len' bytes @ 'cur_speed' */
 535         ms = xfer->len * 8 * 1000 / sdd->cur_speed;
 536         ms += 10; /* some tolerance */
 537
 538         val = msecs_to_loops(ms);
 539         do {
 540                 status = readl(regs + S3C64XX_SPI_STATUS);
 541         } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
 542
 543
 544         /* If it was only Tx */
 545         if (!xfer->rx_buf) {
 546                 sdd->state &= ~TXBUSY;
 547                 return 0;
 548         }
 549
 550         /*
 551          * If the receive length is bigger than the controller fifo
 552          * size, calculate the loops and read the fifo as many times.
 553          * loops = length / max fifo size (calculated by using the
 554          * fifo mask).
 555          * For any size less than the fifo size the below code is
 556          * executed atleast once.
 557          */
 558         loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
 559         buf = xfer->rx_buf;
 560         do {
 561                 /* wait for data to be received in the fifo */
 562                 cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
 563                                                        (loops ? ms : 0));
 564
 565                 switch (sdd->cur_bpw) {
 566                 case 32:
 567                         ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
 568                                      buf, cpy_len / 4);
 569                         break;
 570                 case 16:
 571                         ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
 572                                      buf, cpy_len / 2);
 573                         break;
 574                 default:
 575                         ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
 576                                     buf, cpy_len);
 577                         break;
 578                 }
 579
 580                 buf = buf + cpy_len;
 581         } while (loops--);
 582         sdd->state &= ~RXBUSY;
 583
 584         return 0;
 585 }
 586
 587 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
 588 {
 589         void __iomem *regs = sdd->regs;
 590         u32 val;
 591
 592         /* Disable Clock */
 593         if (sdd->port_conf->clk_from_cmu) {
 594                 clk_disable_unprepare(sdd->src_clk);
 595         } else {
 596                 val = readl(regs + S3C64XX_SPI_CLK_CFG);
 597                 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
 598                 writel(val, regs + S3C64XX_SPI_CLK_CFG);
 599         }
 600
 601         /* Set Polarity and Phase */
 602         val = readl(regs + S3C64XX_SPI_CH_CFG);
 603         val &= ~(S3C64XX_SPI_CH_SLAVE |
 604                         S3C64XX_SPI_CPOL_L |
 605                         S3C64XX_SPI_CPHA_B);
 606
 607         if (sdd->cur_mode & SPI_CPOL)
 608                 val |= S3C64XX_SPI_CPOL_L;
 609
 610         if (sdd->cur_mode & SPI_CPHA)
 611                 val |= S3C64XX_SPI_CPHA_B;
 612
 613         writel(val, regs + S3C64XX_SPI_CH_CFG);
 614
 615         /* Set Channel & DMA Mode */
 616         val = readl(regs + S3C64XX_SPI_MODE_CFG);
 617         val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
 618                         | S3C64XX_SPI_MODE_CH_TSZ_MASK);
 619
 620         switch (sdd->cur_bpw) {
 621         case 32:
 622                 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
 623                 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
 624                 break;
 625         case 16:
 626                 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
 627                 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
 628                 break;
 629         default:
 630                 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
 631                 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
 632                 break;
 633         }
 634
 635         writel(val, regs + S3C64XX_SPI_MODE_CFG);
 636
 637         if (sdd->port_conf->clk_from_cmu) {
 638                 /* Configure Clock */
 639                 /* There is half-multiplier before the SPI */
 640                 clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
 641                 /* Enable Clock */
 642                 clk_prepare_enable(sdd->src_clk);
 643         } else {
 644                 /* Configure Clock */
 645                 val = readl(regs + S3C64XX_SPI_CLK_CFG);
 646                 val &= ~S3C64XX_SPI_PSR_MASK;
 647                 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
 648                                 & S3C64XX_SPI_PSR_MASK);
 649                 writel(val, regs + S3C64XX_SPI_CLK_CFG);
 650
 651                 /* Enable Clock */
 652                 val = readl(regs + S3C64XX_SPI_CLK_CFG);
 653                 val |= S3C64XX_SPI_ENCLK_ENABLE;
 654                 writel(val, regs + S3C64XX_SPI_CLK_CFG);
 655         }
 656 }
 657
 658 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
 659
 660 static int s3c64xx_spi_prepare_message(struct spi_master *master,
 661                                        struct spi_message *msg)
 662 {
 663         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
 664         struct spi_device *spi = msg->spi;
 665         struct s3c64xx_spi_csinfo *cs = spi->controller_data;
 666
 667         /* If Master's(controller) state differs from that needed by Slave */
 668         if (sdd->cur_speed != spi->max_speed_hz
 669                         || sdd->cur_mode != spi->mode
 670                         || sdd->cur_bpw != spi->bits_per_word) {
 671                 sdd->cur_bpw = spi->bits_per_word;
 672                 sdd->cur_speed = spi->max_speed_hz;
 673                 sdd->cur_mode = spi->mode;
 674                 s3c64xx_spi_config(sdd);
 675         }
 676
 677         /* Configure feedback delay */
 678         writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
 679
 680         return 0;
 681 }
 682
 683 static int s3c64xx_spi_transfer_one(struct spi_master *master,
 684                                     struct spi_device *spi,
 685                                     struct spi_transfer *xfer)
 686 {
 687         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
 688         int status;
 689         u32 speed;
 690         u8 bpw;
 691         unsigned long flags;
 692         int use_dma;
 693
 694         reinit_completion(&sdd->xfer_completion);
 695
 696         /* Only BPW and Speed may change across transfers */
 697         bpw = xfer->bits_per_word;
 698         speed = xfer->speed_hz ? : spi->max_speed_hz;
 699
 700         if (xfer->len % (bpw / 8)) {
 701                 dev_err(&spi->dev,
 702                         "Xfer length(%u) not a multiple of word size(%u)\n",
 703                         xfer->len, bpw / 8);
 704                 return -EIO;
 705         }
 706
 707         if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
 708                 sdd->cur_bpw = bpw;
 709                 sdd->cur_speed = speed;
 710                 s3c64xx_spi_config(sdd);
 711         }
 712
 713         /* Polling method for xfers not bigger than FIFO capacity */
 714         use_dma = 0;
 715         if (!is_polling(sdd) &&
 716             (sdd->rx_dma.ch && sdd->tx_dma.ch &&
 717              (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1))))
 718                 use_dma = 1;
 719
 720         spin_lock_irqsave(&sdd->lock, flags);
 721
 722         /* Pending only which is to be done */
 723         sdd->state &= ~RXBUSY;
 724         sdd->state &= ~TXBUSY;
 725
 726         enable_datapath(sdd, spi, xfer, use_dma);
 727
 728         /* Start the signals */
 729         writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 730
 731         spin_unlock_irqrestore(&sdd->lock, flags);
 732
 733         if (use_dma)
 734                 status = wait_for_dma(sdd, xfer);
 735         else
 736                 status = wait_for_pio(sdd, xfer);
 737
 738         if (status) {
 739                 dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
 740                         xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
 741                         (sdd->state & RXBUSY) ? 'f' : 'p',
 742                         (sdd->state & TXBUSY) ? 'f' : 'p',
 743                         xfer->len);
 744
 745                 if (use_dma) {
 746                         if (xfer->tx_buf != NULL
 747                             && (sdd->state & TXBUSY))
 748                                 dmaengine_terminate_all(sdd->tx_dma.ch);
 749                         if (xfer->rx_buf != NULL
 750                             && (sdd->state & RXBUSY))
 751                                 dmaengine_terminate_all(sdd->rx_dma.ch);
 752                 }
 753         } else {
 754                 flush_fifo(sdd);
 755         }
 756
 757         return status;
 758 }
 759
 760 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
 761                                 struct spi_device *spi)
 762 {
 763         struct s3c64xx_spi_csinfo *cs;
 764         struct device_node *slave_np, *data_np = NULL;
 765         struct s3c64xx_spi_driver_data *sdd;
 766         u32 fb_delay = 0;
 767
 768         sdd = spi_master_get_devdata(spi->master);
 769         slave_np = spi->dev.of_node;
 770         if (!slave_np) {
 771                 dev_err(&spi->dev, "device node not found\n");
 772                 return ERR_PTR(-EINVAL);
 773         }
 774
 775         data_np = of_get_child_by_name(slave_np, "controller-data");
 776         if (!data_np) {
 777                 dev_err(&spi->dev, "child node 'controller-data' not found\n");
 778                 return ERR_PTR(-EINVAL);
 779         }
 780
 781         cs = kzalloc(sizeof(*cs), GFP_KERNEL);
 782         if (!cs) {
 783                 dev_err(&spi->dev, "could not allocate memory for controller data\n");
 784                 of_node_put(data_np);
 785                 return ERR_PTR(-ENOMEM);
 786         }
 787
 788         /* The CS line is asserted/deasserted by the gpio pin */
 789         if (sdd->cs_gpio)
 790                 cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
 791
 792         if (!gpio_is_valid(cs->line)) {
 793                 dev_err(&spi->dev, "chip select gpio is not specified or invalid\n");
 794                 kfree(cs);
 795                 of_node_put(data_np);
 796                 return ERR_PTR(-EINVAL);
 797         }
 798
 799         of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
 800         cs->fb_delay = fb_delay;
 801         of_node_put(data_np);
 802         return cs;
 803 }
 804
 805 /*
 806  * Here we only check the validity of requested configuration
 807  * and save the configuration in a local data-structure.
 808  * The controller is actually configured only just before we
 809  * get a message to transfer.
 810  */
 811 static int s3c64xx_spi_setup(struct spi_device *spi)
 812 {
 813         struct s3c64xx_spi_csinfo *cs = spi->controller_data;
 814         struct s3c64xx_spi_driver_data *sdd;
 815         struct s3c64xx_spi_info *sci;
 816         int err;
 817
 818         sdd = spi_master_get_devdata(spi->master);
 819         if (!cs && spi->dev.of_node) {
 820                 cs = s3c64xx_get_slave_ctrldata(spi);
 821                 spi->controller_data = cs;
 822         }
 823
 824         if (IS_ERR_OR_NULL(cs)) {
 825                 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
 826                 return -ENODEV;
 827         }
 828
 829         if (!spi_get_ctldata(spi)) {
 830                 /* Request gpio only if cs line is asserted by gpio pins */
 831                 if (sdd->cs_gpio) {
 832                         err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH,
 833                                         dev_name(&spi->dev));
 834                         if (err) {
 835                                 dev_err(&spi->dev,
 836                                         "Failed to get /CS gpio [%d]: %d\n",
 837                                         cs->line, err);
 838                                 goto err_gpio_req;
 839                         }
 840
 841                         spi->cs_gpio = cs->line;
 842                 }
 843
 844                 spi_set_ctldata(spi, cs);
 845         }
 846
 847         sci = sdd->cntrlr_info;
 848
 849         pm_runtime_get_sync(&sdd->pdev->dev);
 850
 851         /* Check if we can provide the requested rate */
 852         if (!sdd->port_conf->clk_from_cmu) {
 853                 u32 psr, speed;
 854
 855                 /* Max possible */
 856                 speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
 857
 858                 if (spi->max_speed_hz > speed)
 859                         spi->max_speed_hz = speed;
 860
 861                 psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
 862                 psr &= S3C64XX_SPI_PSR_MASK;
 863                 if (psr == S3C64XX_SPI_PSR_MASK)
 864                         psr--;
 865
 866                 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
 867                 if (spi->max_speed_hz < speed) {
 868                         if (psr+1 < S3C64XX_SPI_PSR_MASK) {
 869                                 psr++;
 870                         } else {
 871                                 err = -EINVAL;
 872                                 goto setup_exit;
 873                         }
 874                 }
 875
 876                 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
 877                 if (spi->max_speed_hz >= speed) {
 878                         spi->max_speed_hz = speed;
 879                 } else {
 880                         dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
 881                                 spi->max_speed_hz);
 882                         err = -EINVAL;
 883                         goto setup_exit;
 884                 }
 885         }
 886
 887         pm_runtime_put(&sdd->pdev->dev);
 888         writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 889         return 0;
 890
 891 setup_exit:
 892         pm_runtime_put(&sdd->pdev->dev);
 893         /* setup() returns with device de-selected */
 894         writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 895
 896         gpio_free(cs->line);
 897         spi_set_ctldata(spi, NULL);
 898
 899 err_gpio_req:
 900         if (spi->dev.of_node)
 901                 kfree(cs);
 902
 903         return err;
 904 }
 905
 906 static void s3c64xx_spi_cleanup(struct spi_device *spi)
 907 {
 908         struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
 909         struct s3c64xx_spi_driver_data *sdd;
 910
 911         sdd = spi_master_get_devdata(spi->master);
 912         if (spi->cs_gpio) {
 913                 gpio_free(spi->cs_gpio);
 914                 if (spi->dev.of_node)
 915                         kfree(cs);
 916         }
 917         spi_set_ctldata(spi, NULL);
 918 }
 919
 920 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
 921 {
 922         struct s3c64xx_spi_driver_data *sdd = data;
 923         struct spi_master *spi = sdd->master;
 924         unsigned int val, clr = 0;
 925
 926         val = readl(sdd->regs + S3C64XX_SPI_STATUS);
 927
 928         if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
 929                 clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
 930                 dev_err(&spi->dev, "RX overrun\n");
 931         }
 932         if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
 933                 clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
 934                 dev_err(&spi->dev, "RX underrun\n");
 935         }
 936         if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
 937                 clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
 938                 dev_err(&spi->dev, "TX overrun\n");
 939         }
 940         if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
 941                 clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
 942                 dev_err(&spi->dev, "TX underrun\n");
 943         }
 944
 945         /* Clear the pending irq by setting and then clearing it */
 946         writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
 947         writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
 948
 949         return IRQ_HANDLED;
 950 }
 951
 952 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
 953 {
 954         struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
 955         void __iomem *regs = sdd->regs;
 956         unsigned int val;
 957
 958         sdd->cur_speed = 0;
 959
 960         writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 961
 962         /* Disable Interrupts - we use Polling if not DMA mode */
 963         writel(0, regs + S3C64XX_SPI_INT_EN);
 964
 965         if (!sdd->port_conf->clk_from_cmu)
 966                 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
 967                                 regs + S3C64XX_SPI_CLK_CFG);
 968         writel(0, regs + S3C64XX_SPI_MODE_CFG);
 969         writel(0, regs + S3C64XX_SPI_PACKET_CNT);
 970
 971         /* Clear any irq pending bits, should set and clear the bits */
 972         val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
 973                 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
 974                 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
 975                 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
 976         writel(val, regs + S3C64XX_SPI_PENDING_CLR);
 977         writel(0, regs + S3C64XX_SPI_PENDING_CLR);
 978
 979         writel(0, regs + S3C64XX_SPI_SWAP_CFG);
 980
 981         val = readl(regs + S3C64XX_SPI_MODE_CFG);
 982         val &= ~S3C64XX_SPI_MODE_4BURST;
 983         val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
 984         val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
 985         writel(val, regs + S3C64XX_SPI_MODE_CFG);
 986
 987         flush_fifo(sdd);
 988 }
 989
 990 #ifdef CONFIG_OF
 991 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
 992 {
 993         struct s3c64xx_spi_info *sci;
 994         u32 temp;
 995
 996         sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
 997         if (!sci) {
 998                 dev_err(dev, "memory allocation for spi_info failed\n");
 999                 return ERR_PTR(-ENOMEM);
1000         }
1001
1002         if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1003                 dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1004                 sci->src_clk_nr = 0;
1005         } else {
1006                 sci->src_clk_nr = temp;
1007         }
1008
1009         if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1010                 dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1011                 sci->num_cs = 1;
1012         } else {
1013                 sci->num_cs = temp;
1014         }
1015
1016         return sci;
1017 }
1018 #else
1019 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1020 {
1021         return dev_get_platdata(dev);
1022 }
1023 #endif
1024
1025 static const struct of_device_id s3c64xx_spi_dt_match[];
1026
1027 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1028                                                 struct platform_device *pdev)
1029 {
1030 #ifdef CONFIG_OF
1031         if (pdev->dev.of_node) {
1032                 const struct of_device_id *match;
1033                 match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1034                 return (struct s3c64xx_spi_port_config *)match->data;
1035         }
1036 #endif
1037         return (struct s3c64xx_spi_port_config *)
1038                          platform_get_device_id(pdev)->driver_data;
1039 }
1040
1041 static int s3c64xx_spi_probe(struct platform_device *pdev)
1042 {
1043         struct resource *mem_res;
1044         struct resource *res;
1045         struct s3c64xx_spi_driver_data *sdd;
1046         struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1047         struct spi_master *master;
1048         int ret, irq;
1049         char clk_name[16];
1050
1051         if (!sci && pdev->dev.of_node) {
1052                 sci = s3c64xx_spi_parse_dt(&pdev->dev);
1053                 if (IS_ERR(sci))
1054                         return PTR_ERR(sci);
1055         }
1056
1057         if (!sci) {
1058                 dev_err(&pdev->dev, "platform_data missing!\n");
1059                 return -ENODEV;
1060         }
1061
1062         mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1063         if (mem_res == NULL) {
1064                 dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1065                 return -ENXIO;
1066         }
1067
1068         irq = platform_get_irq(pdev, 0);
1069         if (irq < 0) {
1070                 dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1071                 return irq;
1072         }
1073
1074         master = spi_alloc_master(&pdev->dev,
1075                                 sizeof(struct s3c64xx_spi_driver_data));
1076         if (master == NULL) {
1077                 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1078                 return -ENOMEM;
1079         }
1080
1081         platform_set_drvdata(pdev, master);
1082
1083         sdd = spi_master_get_devdata(master);
1084         sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1085         sdd->master = master;
1086         sdd->cntrlr_info = sci;
1087         sdd->pdev = pdev;
1088         sdd->sfr_start = mem_res->start;
1089         sdd->cs_gpio = true;
1090         if (pdev->dev.of_node) {
1091                 if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL))
1092                         sdd->cs_gpio = false;
1093
1094                 ret = of_alias_get_id(pdev->dev.of_node, "spi");
1095                 if (ret < 0) {
1096                         dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1097                                 ret);
1098                         goto err0;
1099                 }
1100                 sdd->port_id = ret;
1101         } else {
1102                 sdd->port_id = pdev->id;
1103         }
1104
1105         sdd->cur_bpw = 8;
1106
1107         if (!sdd->pdev->dev.of_node) {
1108                 res = platform_get_resource(pdev, IORESOURCE_DMA,  0);
1109                 if (!res) {
1110                         dev_warn(&pdev->dev, "Unable to get SPI tx dma resource. Switching to poll mode\n");
1111                         sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1112                 } else
1113                         sdd->tx_dma.dmach = res->start;
1114
1115                 res = platform_get_resource(pdev, IORESOURCE_DMA,  1);
1116                 if (!res) {
1117                         dev_warn(&pdev->dev, "Unable to get SPI rx dma resource. Switching to poll mode\n");
1118                         sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL;
1119                 } else
1120                         sdd->rx_dma.dmach = res->start;
1121         }
1122
1123         sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1124         sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1125
1126         master->dev.of_node = pdev->dev.of_node;
1127         master->bus_num = sdd->port_id;
1128         master->setup = s3c64xx_spi_setup;
1129         master->cleanup = s3c64xx_spi_cleanup;
1130         master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1131         master->prepare_message = s3c64xx_spi_prepare_message;
1132         master->transfer_one = s3c64xx_spi_transfer_one;
1133         master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1134         master->num_chipselect = sci->num_cs;
1135         master->dma_alignment = 8;
1136         master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1137                                         SPI_BPW_MASK(8);
1138         /* the spi->mode bits understood by this driver: */
1139         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1140         master->auto_runtime_pm = true;
1141         if (!is_polling(sdd))
1142                 master->can_dma = s3c64xx_spi_can_dma;
1143
1144         sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1145         if (IS_ERR(sdd->regs)) {
1146                 ret = PTR_ERR(sdd->regs);
1147                 goto err0;
1148         }
1149
1150         if (sci->cfg_gpio && sci->cfg_gpio()) {
1151                 dev_err(&pdev->dev, "Unable to config gpio\n");
1152                 ret = -EBUSY;
1153                 goto err0;
1154         }
1155
1156         /* Setup clocks */
1157         sdd->clk = devm_clk_get(&pdev->dev, "spi");
1158         if (IS_ERR(sdd->clk)) {
1159                 dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1160                 ret = PTR_ERR(sdd->clk);
1161                 goto err0;
1162         }
1163
1164         if (clk_prepare_enable(sdd->clk)) {
1165                 dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1166                 ret = -EBUSY;
1167                 goto err0;
1168         }
1169
1170         sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1171         sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1172         if (IS_ERR(sdd->src_clk)) {
1173                 dev_err(&pdev->dev,
1174                         "Unable to acquire clock '%s'\n", clk_name);
1175                 ret = PTR_ERR(sdd->src_clk);
1176                 goto err2;
1177         }
1178
1179         if (clk_prepare_enable(sdd->src_clk)) {
1180                 dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1181                 ret = -EBUSY;
1182                 goto err2;
1183         }
1184
1185         /* Setup Deufult Mode */
1186         s3c64xx_spi_hwinit(sdd, sdd->port_id);
1187
1188         spin_lock_init(&sdd->lock);
1189         init_completion(&sdd->xfer_completion);
1190
1191         ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1192                                 "spi-s3c64xx", sdd);
1193         if (ret != 0) {
1194                 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1195                         irq, ret);
1196                 goto err3;
1197         }
1198
1199         writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1200                S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1201                sdd->regs + S3C64XX_SPI_INT_EN);
1202
1203         pm_runtime_set_active(&pdev->dev);
1204         pm_runtime_enable(&pdev->dev);
1205
1206         ret = devm_spi_register_master(&pdev->dev, master);
1207         if (ret != 0) {
1208                 dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1209                 goto err3;
1210         }
1211
1212         dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1213                                         sdd->port_id, master->num_chipselect);
1214         dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tDMA=[Rx-%d, Tx-%d]\n",
1215                                         mem_res,
1216                                         sdd->rx_dma.dmach, sdd->tx_dma.dmach);
1217
1218         return 0;
1219
1220 err3:
1221         clk_disable_unprepare(sdd->src_clk);
1222 err2:
1223         clk_disable_unprepare(sdd->clk);
1224 err0:
1225         spi_master_put(master);
1226
1227         return ret;
1228 }
1229
1230 static int s3c64xx_spi_remove(struct platform_device *pdev)
1231 {
1232         struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
1233         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1234
1235         pm_runtime_disable(&pdev->dev);
1236
1237         writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1238
1239         clk_disable_unprepare(sdd->src_clk);
1240
1241         clk_disable_unprepare(sdd->clk);
1242
1243         return 0;
1244 }
1245
1246 #ifdef CONFIG_PM_SLEEP
1247 static int s3c64xx_spi_suspend(struct device *dev)
1248 {
1249         struct spi_master *master = dev_get_drvdata(dev);
1250         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1251
1252         int ret = spi_master_suspend(master);
1253         if (ret)
1254                 return ret;
1255
1256         if (!pm_runtime_suspended(dev)) {
1257                 clk_disable_unprepare(sdd->clk);
1258                 clk_disable_unprepare(sdd->src_clk);
1259         }
1260
1261         sdd->cur_speed = 0; /* Output Clock is stopped */
1262
1263         return 0;
1264 }
1265
1266 static int s3c64xx_spi_resume(struct device *dev)
1267 {
1268         struct spi_master *master = dev_get_drvdata(dev);
1269         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1270         struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1271
1272         if (sci->cfg_gpio)
1273                 sci->cfg_gpio();
1274
1275         if (!pm_runtime_suspended(dev)) {
1276                 clk_prepare_enable(sdd->src_clk);
1277                 clk_prepare_enable(sdd->clk);
1278         }
1279
1280         s3c64xx_spi_hwinit(sdd, sdd->port_id);
1281
1282         return spi_master_resume(master);
1283 }
1284 #endif /* CONFIG_PM_SLEEP */
1285
1286 #ifdef CONFIG_PM_RUNTIME
1287 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1288 {
1289         struct spi_master *master = dev_get_drvdata(dev);
1290         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1291
1292         clk_disable_unprepare(sdd->clk);
1293         clk_disable_unprepare(sdd->src_clk);
1294
1295         return 0;
1296 }
1297
1298 static int s3c64xx_spi_runtime_resume(struct device *dev)
1299 {
1300         struct spi_master *master = dev_get_drvdata(dev);
1301         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1302         int ret;
1303
1304         ret = clk_prepare_enable(sdd->src_clk);
1305         if (ret != 0)
1306                 return ret;
1307
1308         ret = clk_prepare_enable(sdd->clk);
1309         if (ret != 0) {
1310                 clk_disable_unprepare(sdd->src_clk);
1311                 return ret;
1312         }
1313
1314         return 0;
1315 }
1316 #endif /* CONFIG_PM_RUNTIME */
1317
1318 static const struct dev_pm_ops s3c64xx_spi_pm = {
1319         SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1320         SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1321                            s3c64xx_spi_runtime_resume, NULL)
1322 };
1323
1324 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1325         .fifo_lvl_mask  = { 0x7f },
1326         .rx_lvl_offset  = 13,
1327         .tx_st_done     = 21,
1328         .high_speed     = true,
1329 };
1330
1331 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1332         .fifo_lvl_mask  = { 0x7f, 0x7F },
1333         .rx_lvl_offset  = 13,
1334         .tx_st_done     = 21,
1335 };
1336
1337 static struct s3c64xx_spi_port_config s5p64x0_spi_port_config = {
1338         .fifo_lvl_mask  = { 0x1ff, 0x7F },
1339         .rx_lvl_offset  = 15,
1340         .tx_st_done     = 25,
1341 };
1342
1343 static struct s3c64xx_spi_port_config s5pc100_spi_port_config = {
1344         .fifo_lvl_mask  = { 0x7f, 0x7F },
1345         .rx_lvl_offset  = 13,
1346         .tx_st_done     = 21,
1347         .high_speed     = true,
1348 };
1349
1350 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1351         .fifo_lvl_mask  = { 0x1ff, 0x7F },
1352         .rx_lvl_offset  = 15,
1353         .tx_st_done     = 25,
1354         .high_speed     = true,
1355 };
1356
1357 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1358         .fifo_lvl_mask  = { 0x1ff, 0x7F, 0x7F },
1359         .rx_lvl_offset  = 15,
1360         .tx_st_done     = 25,
1361         .high_speed     = true,
1362         .clk_from_cmu   = true,
1363 };
1364
1365 static struct s3c64xx_spi_port_config exynos5440_spi_port_config = {
1366         .fifo_lvl_mask  = { 0x1ff },
1367         .rx_lvl_offset  = 15,
1368         .tx_st_done     = 25,
1369         .high_speed     = true,
1370         .clk_from_cmu   = true,
1371         .quirks         = S3C64XX_SPI_QUIRK_POLL,
1372 };
1373
1374 static struct platform_device_id s3c64xx_spi_driver_ids[] = {
1375         {
1376                 .name           = "s3c2443-spi",
1377                 .driver_data    = (kernel_ulong_t)&s3c2443_spi_port_config,
1378         }, {
1379                 .name           = "s3c6410-spi",
1380                 .driver_data    = (kernel_ulong_t)&s3c6410_spi_port_config,
1381         }, {
1382                 .name           = "s5p64x0-spi",
1383                 .driver_data    = (kernel_ulong_t)&s5p64x0_spi_port_config,
1384         }, {
1385                 .name           = "s5pc100-spi",
1386                 .driver_data    = (kernel_ulong_t)&s5pc100_spi_port_config,
1387         }, {
1388                 .name           = "s5pv210-spi",
1389                 .driver_data    = (kernel_ulong_t)&s5pv210_spi_port_config,
1390         }, {
1391                 .name           = "exynos4210-spi",
1392                 .driver_data    = (kernel_ulong_t)&exynos4_spi_port_config,
1393         },
1394         { },
1395 };
1396
1397 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1398         { .compatible = "samsung,s3c2443-spi",
1399                         .data = (void *)&s3c2443_spi_port_config,
1400         },
1401         { .compatible = "samsung,s3c6410-spi",
1402                         .data = (void *)&s3c6410_spi_port_config,
1403         },
1404         { .compatible = "samsung,s5pc100-spi",
1405                         .data = (void *)&s5pc100_spi_port_config,
1406         },
1407         { .compatible = "samsung,s5pv210-spi",
1408                         .data = (void *)&s5pv210_spi_port_config,
1409         },
1410         { .compatible = "samsung,exynos4210-spi",
1411                         .data = (void *)&exynos4_spi_port_config,
1412         },
1413         { .compatible = "samsung,exynos5440-spi",
1414                         .data = (void *)&exynos5440_spi_port_config,
1415         },
1416         { },
1417 };
1418 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1419
1420 static struct platform_driver s3c64xx_spi_driver = {
1421         .driver = {
1422                 .name   = "s3c64xx-spi",
1423                 .owner = THIS_MODULE,
1424                 .pm = &s3c64xx_spi_pm,
1425                 .of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1426         },
1427         .probe = s3c64xx_spi_probe,
1428         .remove = s3c64xx_spi_remove,
1429         .id_table = s3c64xx_spi_driver_ids,
1430 };
1431 MODULE_ALIAS("platform:s3c64xx-spi");
1432
1433 module_platform_driver(s3c64xx_spi_driver);
1434
1435 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1436 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1437 MODULE_LICENSE("GPL");