drivers/spi/spi-s3c64xx.c

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This source file includes following definitions.
s3c64xx_flush_fifo
s3c64xx_spi_dmacb
prepare_dma
s3c64xx_spi_set_cs
s3c64xx_spi_prepare_transfer
s3c64xx_spi_can_dma
s3c64xx_enable_datapath
s3c64xx_spi_wait_for_timeout
s3c64xx_wait_for_dma
s3c64xx_wait_for_pio
s3c64xx_spi_config
s3c64xx_spi_prepare_message
s3c64xx_spi_transfer_one
s3c64xx_get_slave_ctrldata
s3c64xx_spi_setup
s3c64xx_spi_cleanup
s3c64xx_spi_irq
s3c64xx_spi_hwinit
s3c64xx_spi_parse_dt
s3c64xx_spi_parse_dt
s3c64xx_spi_get_port_config
s3c64xx_spi_probe
s3c64xx_spi_remove
s3c64xx_spi_suspend
s3c64xx_spi_resume
s3c64xx_spi_runtime_suspend
s3c64xx_spi_runtime_resume
   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // Copyright (c) 2009 Samsung Electronics Co., Ltd.
   4 //      Jaswinder Singh <jassi.brar@samsung.com>
   5 
   6 #include <linux/init.h>
   7 #include <linux/module.h>
   8 #include <linux/interrupt.h>
   9 #include <linux/delay.h>
  10 #include <linux/clk.h>
  11 #include <linux/dma-mapping.h>
  12 #include <linux/dmaengine.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/pm_runtime.h>
  15 #include <linux/spi/spi.h>
  16 #include <linux/gpio.h>
  17 #include <linux/of.h>
  18 #include <linux/of_gpio.h>
  19 
  20 #include <linux/platform_data/spi-s3c64xx.h>
  21 
  22 #define MAX_SPI_PORTS           6
  23 #define S3C64XX_SPI_QUIRK_POLL          (1 << 0)
  24 #define S3C64XX_SPI_QUIRK_CS_AUTO       (1 << 1)
  25 #define AUTOSUSPEND_TIMEOUT     2000
  26 
  27 /* Registers and bit-fields */
  28 
  29 #define S3C64XX_SPI_CH_CFG              0x00
  30 #define S3C64XX_SPI_CLK_CFG             0x04
  31 #define S3C64XX_SPI_MODE_CFG            0x08
  32 #define S3C64XX_SPI_SLAVE_SEL           0x0C
  33 #define S3C64XX_SPI_INT_EN              0x10
  34 #define S3C64XX_SPI_STATUS              0x14
  35 #define S3C64XX_SPI_TX_DATA             0x18
  36 #define S3C64XX_SPI_RX_DATA             0x1C
  37 #define S3C64XX_SPI_PACKET_CNT          0x20
  38 #define S3C64XX_SPI_PENDING_CLR         0x24
  39 #define S3C64XX_SPI_SWAP_CFG            0x28
  40 #define S3C64XX_SPI_FB_CLK              0x2C
  41 
  42 #define S3C64XX_SPI_CH_HS_EN            (1<<6)  /* High Speed Enable */
  43 #define S3C64XX_SPI_CH_SW_RST           (1<<5)
  44 #define S3C64XX_SPI_CH_SLAVE            (1<<4)
  45 #define S3C64XX_SPI_CPOL_L              (1<<3)
  46 #define S3C64XX_SPI_CPHA_B              (1<<2)
  47 #define S3C64XX_SPI_CH_RXCH_ON          (1<<1)
  48 #define S3C64XX_SPI_CH_TXCH_ON          (1<<0)
  49 
  50 #define S3C64XX_SPI_CLKSEL_SRCMSK       (3<<9)
  51 #define S3C64XX_SPI_CLKSEL_SRCSHFT      9
  52 #define S3C64XX_SPI_ENCLK_ENABLE        (1<<8)
  53 #define S3C64XX_SPI_PSR_MASK            0xff
  54 
  55 #define S3C64XX_SPI_MODE_CH_TSZ_BYTE            (0<<29)
  56 #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD        (1<<29)
  57 #define S3C64XX_SPI_MODE_CH_TSZ_WORD            (2<<29)
  58 #define S3C64XX_SPI_MODE_CH_TSZ_MASK            (3<<29)
  59 #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE           (0<<17)
  60 #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD       (1<<17)
  61 #define S3C64XX_SPI_MODE_BUS_TSZ_WORD           (2<<17)
  62 #define S3C64XX_SPI_MODE_BUS_TSZ_MASK           (3<<17)
  63 #define S3C64XX_SPI_MODE_RXDMA_ON               (1<<2)
  64 #define S3C64XX_SPI_MODE_TXDMA_ON               (1<<1)
  65 #define S3C64XX_SPI_MODE_4BURST                 (1<<0)
  66 
  67 #define S3C64XX_SPI_SLAVE_AUTO                  (1<<1)
  68 #define S3C64XX_SPI_SLAVE_SIG_INACT             (1<<0)
  69 #define S3C64XX_SPI_SLAVE_NSC_CNT_2             (2<<4)
  70 
  71 #define S3C64XX_SPI_INT_TRAILING_EN             (1<<6)
  72 #define S3C64XX_SPI_INT_RX_OVERRUN_EN           (1<<5)
  73 #define S3C64XX_SPI_INT_RX_UNDERRUN_EN          (1<<4)
  74 #define S3C64XX_SPI_INT_TX_OVERRUN_EN           (1<<3)
  75 #define S3C64XX_SPI_INT_TX_UNDERRUN_EN          (1<<2)
  76 #define S3C64XX_SPI_INT_RX_FIFORDY_EN           (1<<1)
  77 #define S3C64XX_SPI_INT_TX_FIFORDY_EN           (1<<0)
  78 
  79 #define S3C64XX_SPI_ST_RX_OVERRUN_ERR           (1<<5)
  80 #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR          (1<<4)
  81 #define S3C64XX_SPI_ST_TX_OVERRUN_ERR           (1<<3)
  82 #define S3C64XX_SPI_ST_TX_UNDERRUN_ERR          (1<<2)
  83 #define S3C64XX_SPI_ST_RX_FIFORDY               (1<<1)
  84 #define S3C64XX_SPI_ST_TX_FIFORDY               (1<<0)
  85 
  86 #define S3C64XX_SPI_PACKET_CNT_EN               (1<<16)
  87 
  88 #define S3C64XX_SPI_PND_TX_UNDERRUN_CLR         (1<<4)
  89 #define S3C64XX_SPI_PND_TX_OVERRUN_CLR          (1<<3)
  90 #define S3C64XX_SPI_PND_RX_UNDERRUN_CLR         (1<<2)
  91 #define S3C64XX_SPI_PND_RX_OVERRUN_CLR          (1<<1)
  92 #define S3C64XX_SPI_PND_TRAILING_CLR            (1<<0)
  93 
  94 #define S3C64XX_SPI_SWAP_RX_HALF_WORD           (1<<7)
  95 #define S3C64XX_SPI_SWAP_RX_BYTE                (1<<6)
  96 #define S3C64XX_SPI_SWAP_RX_BIT                 (1<<5)
  97 #define S3C64XX_SPI_SWAP_RX_EN                  (1<<4)
  98 #define S3C64XX_SPI_SWAP_TX_HALF_WORD           (1<<3)
  99 #define S3C64XX_SPI_SWAP_TX_BYTE                (1<<2)
 100 #define S3C64XX_SPI_SWAP_TX_BIT                 (1<<1)
 101 #define S3C64XX_SPI_SWAP_TX_EN                  (1<<0)
 102 
 103 #define S3C64XX_SPI_FBCLK_MSK                   (3<<0)
 104 
 105 #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
 106 #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
 107                                 (1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
 108 #define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
 109 #define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
 110                                         FIFO_LVL_MASK(i))
 111 
 112 #define S3C64XX_SPI_MAX_TRAILCNT        0x3ff
 113 #define S3C64XX_SPI_TRAILCNT_OFF        19
 114 
 115 #define S3C64XX_SPI_TRAILCNT            S3C64XX_SPI_MAX_TRAILCNT
 116 
 117 #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
 118 #define is_polling(x)   (x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
 119 
 120 #define RXBUSY    (1<<2)
 121 #define TXBUSY    (1<<3)
 122 
 123 struct s3c64xx_spi_dma_data {
 124         struct dma_chan *ch;
 125         enum dma_transfer_direction direction;
 126 };
 127 
 128 /**
 129  * struct s3c64xx_spi_info - SPI Controller hardware info
 130  * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
 131  * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
 132  * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
 133  * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
 134  * @clk_from_cmu: True, if the controller does not include a clock mux and
 135  *      prescaler unit.
 136  *
 137  * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
 138  * differ in some aspects such as the size of the fifo and spi bus clock
 139  * setup. Such differences are specified to the driver using this structure
 140  * which is provided as driver data to the driver.
 141  */
 142 struct s3c64xx_spi_port_config {
 143         int     fifo_lvl_mask[MAX_SPI_PORTS];
 144         int     rx_lvl_offset;
 145         int     tx_st_done;
 146         int     quirks;
 147         bool    high_speed;
 148         bool    clk_from_cmu;
 149         bool    clk_ioclk;
 150 };
 151 
 152 /**
 153  * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
 154  * @clk: Pointer to the spi clock.
 155  * @src_clk: Pointer to the clock used to generate SPI signals.
 156  * @ioclk: Pointer to the i/o clock between master and slave
 157  * @master: Pointer to the SPI Protocol master.
 158  * @cntrlr_info: Platform specific data for the controller this driver manages.
 159  * @lock: Controller specific lock.
 160  * @state: Set of FLAGS to indicate status.
 161  * @rx_dmach: Controller's DMA channel for Rx.
 162  * @tx_dmach: Controller's DMA channel for Tx.
 163  * @sfr_start: BUS address of SPI controller regs.
 164  * @regs: Pointer to ioremap'ed controller registers.
 165  * @irq: interrupt
 166  * @xfer_completion: To indicate completion of xfer task.
 167  * @cur_mode: Stores the active configuration of the controller.
 168  * @cur_bpw: Stores the active bits per word settings.
 169  * @cur_speed: Stores the active xfer clock speed.
 170  */
 171 struct s3c64xx_spi_driver_data {
 172         void __iomem                    *regs;
 173         struct clk                      *clk;
 174         struct clk                      *src_clk;
 175         struct clk                      *ioclk;
 176         struct platform_device          *pdev;
 177         struct spi_master               *master;
 178         struct s3c64xx_spi_info  *cntrlr_info;
 179         spinlock_t                      lock;
 180         unsigned long                   sfr_start;
 181         struct completion               xfer_completion;
 182         unsigned                        state;
 183         unsigned                        cur_mode, cur_bpw;
 184         unsigned                        cur_speed;
 185         struct s3c64xx_spi_dma_data     rx_dma;
 186         struct s3c64xx_spi_dma_data     tx_dma;
 187         struct s3c64xx_spi_port_config  *port_conf;
 188         unsigned int                    port_id;
 189 };
 190 
 191 static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd)
 192 {
 193         void __iomem *regs = sdd->regs;
 194         unsigned long loops;
 195         u32 val;
 196 
 197         writel(0, regs + S3C64XX_SPI_PACKET_CNT);
 198 
 199         val = readl(regs + S3C64XX_SPI_CH_CFG);
 200         val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
 201         writel(val, regs + S3C64XX_SPI_CH_CFG);
 202 
 203         val = readl(regs + S3C64XX_SPI_CH_CFG);
 204         val |= S3C64XX_SPI_CH_SW_RST;
 205         val &= ~S3C64XX_SPI_CH_HS_EN;
 206         writel(val, regs + S3C64XX_SPI_CH_CFG);
 207 
 208         /* Flush TxFIFO*/
 209         loops = msecs_to_loops(1);
 210         do {
 211                 val = readl(regs + S3C64XX_SPI_STATUS);
 212         } while (TX_FIFO_LVL(val, sdd) && loops--);
 213 
 214         if (loops == 0)
 215                 dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
 216 
 217         /* Flush RxFIFO*/
 218         loops = msecs_to_loops(1);
 219         do {
 220                 val = readl(regs + S3C64XX_SPI_STATUS);
 221                 if (RX_FIFO_LVL(val, sdd))
 222                         readl(regs + S3C64XX_SPI_RX_DATA);
 223                 else
 224                         break;
 225         } while (loops--);
 226 
 227         if (loops == 0)
 228                 dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
 229 
 230         val = readl(regs + S3C64XX_SPI_CH_CFG);
 231         val &= ~S3C64XX_SPI_CH_SW_RST;
 232         writel(val, regs + S3C64XX_SPI_CH_CFG);
 233 
 234         val = readl(regs + S3C64XX_SPI_MODE_CFG);
 235         val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
 236         writel(val, regs + S3C64XX_SPI_MODE_CFG);
 237 }
 238 
 239 static void s3c64xx_spi_dmacb(void *data)
 240 {
 241         struct s3c64xx_spi_driver_data *sdd;
 242         struct s3c64xx_spi_dma_data *dma = data;
 243         unsigned long flags;
 244 
 245         if (dma->direction == DMA_DEV_TO_MEM)
 246                 sdd = container_of(data,
 247                         struct s3c64xx_spi_driver_data, rx_dma);
 248         else
 249                 sdd = container_of(data,
 250                         struct s3c64xx_spi_driver_data, tx_dma);
 251 
 252         spin_lock_irqsave(&sdd->lock, flags);
 253 
 254         if (dma->direction == DMA_DEV_TO_MEM) {
 255                 sdd->state &= ~RXBUSY;
 256                 if (!(sdd->state & TXBUSY))
 257                         complete(&sdd->xfer_completion);
 258         } else {
 259                 sdd->state &= ~TXBUSY;
 260                 if (!(sdd->state & RXBUSY))
 261                         complete(&sdd->xfer_completion);
 262         }
 263 
 264         spin_unlock_irqrestore(&sdd->lock, flags);
 265 }
 266 
 267 static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
 268                         struct sg_table *sgt)
 269 {
 270         struct s3c64xx_spi_driver_data *sdd;
 271         struct dma_slave_config config;
 272         struct dma_async_tx_descriptor *desc;
 273 
 274         memset(&config, 0, sizeof(config));
 275 
 276         if (dma->direction == DMA_DEV_TO_MEM) {
 277                 sdd = container_of((void *)dma,
 278                         struct s3c64xx_spi_driver_data, rx_dma);
 279                 config.direction = dma->direction;
 280                 config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
 281                 config.src_addr_width = sdd->cur_bpw / 8;
 282                 config.src_maxburst = 1;
 283                 dmaengine_slave_config(dma->ch, &config);
 284         } else {
 285                 sdd = container_of((void *)dma,
 286                         struct s3c64xx_spi_driver_data, tx_dma);
 287                 config.direction = dma->direction;
 288                 config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
 289                 config.dst_addr_width = sdd->cur_bpw / 8;
 290                 config.dst_maxburst = 1;
 291                 dmaengine_slave_config(dma->ch, &config);
 292         }
 293 
 294         desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
 295                                        dma->direction, DMA_PREP_INTERRUPT);
 296 
 297         desc->callback = s3c64xx_spi_dmacb;
 298         desc->callback_param = dma;
 299 
 300         dmaengine_submit(desc);
 301         dma_async_issue_pending(dma->ch);
 302 }
 303 
 304 static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
 305 {
 306         struct s3c64xx_spi_driver_data *sdd =
 307                                         spi_master_get_devdata(spi->master);
 308 
 309         if (sdd->cntrlr_info->no_cs)
 310                 return;
 311 
 312         if (enable) {
 313                 if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
 314                         writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 315                 } else {
 316                         u32 ssel = readl(sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 317 
 318                         ssel |= (S3C64XX_SPI_SLAVE_AUTO |
 319                                                 S3C64XX_SPI_SLAVE_NSC_CNT_2);
 320                         writel(ssel, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 321                 }
 322         } else {
 323                 if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
 324                         writel(S3C64XX_SPI_SLAVE_SIG_INACT,
 325                                sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 326         }
 327 }
 328 
 329 static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
 330 {
 331         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
 332 
 333         if (is_polling(sdd))
 334                 return 0;
 335 
 336         spi->dma_rx = sdd->rx_dma.ch;
 337         spi->dma_tx = sdd->tx_dma.ch;
 338 
 339         return 0;
 340 }
 341 
 342 static bool s3c64xx_spi_can_dma(struct spi_master *master,
 343                                 struct spi_device *spi,
 344                                 struct spi_transfer *xfer)
 345 {
 346         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
 347 
 348         return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
 349 }
 350 
 351 static void s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data *sdd,
 352                                     struct spi_transfer *xfer, int dma_mode)
 353 {
 354         void __iomem *regs = sdd->regs;
 355         u32 modecfg, chcfg;
 356 
 357         modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
 358         modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
 359 
 360         chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
 361         chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
 362 
 363         if (dma_mode) {
 364                 chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
 365         } else {
 366                 /* Always shift in data in FIFO, even if xfer is Tx only,
 367                  * this helps setting PCKT_CNT value for generating clocks
 368                  * as exactly needed.
 369                  */
 370                 chcfg |= S3C64XX_SPI_CH_RXCH_ON;
 371                 writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
 372                                         | S3C64XX_SPI_PACKET_CNT_EN,
 373                                         regs + S3C64XX_SPI_PACKET_CNT);
 374         }
 375 
 376         if (xfer->tx_buf != NULL) {
 377                 sdd->state |= TXBUSY;
 378                 chcfg |= S3C64XX_SPI_CH_TXCH_ON;
 379                 if (dma_mode) {
 380                         modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
 381                         prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
 382                 } else {
 383                         switch (sdd->cur_bpw) {
 384                         case 32:
 385                                 iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
 386                                         xfer->tx_buf, xfer->len / 4);
 387                                 break;
 388                         case 16:
 389                                 iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
 390                                         xfer->tx_buf, xfer->len / 2);
 391                                 break;
 392                         default:
 393                                 iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
 394                                         xfer->tx_buf, xfer->len);
 395                                 break;
 396                         }
 397                 }
 398         }
 399 
 400         if (xfer->rx_buf != NULL) {
 401                 sdd->state |= RXBUSY;
 402 
 403                 if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
 404                                         && !(sdd->cur_mode & SPI_CPHA))
 405                         chcfg |= S3C64XX_SPI_CH_HS_EN;
 406 
 407                 if (dma_mode) {
 408                         modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
 409                         chcfg |= S3C64XX_SPI_CH_RXCH_ON;
 410                         writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
 411                                         | S3C64XX_SPI_PACKET_CNT_EN,
 412                                         regs + S3C64XX_SPI_PACKET_CNT);
 413                         prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
 414                 }
 415         }
 416 
 417         writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
 418         writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
 419 }
 420 
 421 static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
 422                                         int timeout_ms)
 423 {
 424         void __iomem *regs = sdd->regs;
 425         unsigned long val = 1;
 426         u32 status;
 427 
 428         /* max fifo depth available */
 429         u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
 430 
 431         if (timeout_ms)
 432                 val = msecs_to_loops(timeout_ms);
 433 
 434         do {
 435                 status = readl(regs + S3C64XX_SPI_STATUS);
 436         } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
 437 
 438         /* return the actual received data length */
 439         return RX_FIFO_LVL(status, sdd);
 440 }
 441 
 442 static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
 443                                 struct spi_transfer *xfer)
 444 {
 445         void __iomem *regs = sdd->regs;
 446         unsigned long val;
 447         u32 status;
 448         int ms;
 449 
 450         /* millisecs to xfer 'len' bytes @ 'cur_speed' */
 451         ms = xfer->len * 8 * 1000 / sdd->cur_speed;
 452         ms += 10; /* some tolerance */
 453 
 454         val = msecs_to_jiffies(ms) + 10;
 455         val = wait_for_completion_timeout(&sdd->xfer_completion, val);
 456 
 457         /*
 458          * If the previous xfer was completed within timeout, then
 459          * proceed further else return -EIO.
 460          * DmaTx returns after simply writing data in the FIFO,
 461          * w/o waiting for real transmission on the bus to finish.
 462          * DmaRx returns only after Dma read data from FIFO which
 463          * needs bus transmission to finish, so we don't worry if
 464          * Xfer involved Rx(with or without Tx).
 465          */
 466         if (val && !xfer->rx_buf) {
 467                 val = msecs_to_loops(10);
 468                 status = readl(regs + S3C64XX_SPI_STATUS);
 469                 while ((TX_FIFO_LVL(status, sdd)
 470                         || !S3C64XX_SPI_ST_TX_DONE(status, sdd))
 471                        && --val) {
 472                         cpu_relax();
 473                         status = readl(regs + S3C64XX_SPI_STATUS);
 474                 }
 475 
 476         }
 477 
 478         /* If timed out while checking rx/tx status return error */
 479         if (!val)
 480                 return -EIO;
 481 
 482         return 0;
 483 }
 484 
 485 static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
 486                                 struct spi_transfer *xfer)
 487 {
 488         void __iomem *regs = sdd->regs;
 489         unsigned long val;
 490         u32 status;
 491         int loops;
 492         u32 cpy_len;
 493         u8 *buf;
 494         int ms;
 495 
 496         /* millisecs to xfer 'len' bytes @ 'cur_speed' */
 497         ms = xfer->len * 8 * 1000 / sdd->cur_speed;
 498         ms += 10; /* some tolerance */
 499 
 500         val = msecs_to_loops(ms);
 501         do {
 502                 status = readl(regs + S3C64XX_SPI_STATUS);
 503         } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
 504 
 505         if (!val)
 506                 return -EIO;
 507 
 508         /* If it was only Tx */
 509         if (!xfer->rx_buf) {
 510                 sdd->state &= ~TXBUSY;
 511                 return 0;
 512         }
 513 
 514         /*
 515          * If the receive length is bigger than the controller fifo
 516          * size, calculate the loops and read the fifo as many times.
 517          * loops = length / max fifo size (calculated by using the
 518          * fifo mask).
 519          * For any size less than the fifo size the below code is
 520          * executed atleast once.
 521          */
 522         loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
 523         buf = xfer->rx_buf;
 524         do {
 525                 /* wait for data to be received in the fifo */
 526                 cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
 527                                                        (loops ? ms : 0));
 528 
 529                 switch (sdd->cur_bpw) {
 530                 case 32:
 531                         ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
 532                                      buf, cpy_len / 4);
 533                         break;
 534                 case 16:
 535                         ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
 536                                      buf, cpy_len / 2);
 537                         break;
 538                 default:
 539                         ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
 540                                     buf, cpy_len);
 541                         break;
 542                 }
 543 
 544                 buf = buf + cpy_len;
 545         } while (loops--);
 546         sdd->state &= ~RXBUSY;
 547 
 548         return 0;
 549 }
 550 
 551 static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
 552 {
 553         void __iomem *regs = sdd->regs;
 554         u32 val;
 555 
 556         /* Disable Clock */
 557         if (!sdd->port_conf->clk_from_cmu) {
 558                 val = readl(regs + S3C64XX_SPI_CLK_CFG);
 559                 val &= ~S3C64XX_SPI_ENCLK_ENABLE;
 560                 writel(val, regs + S3C64XX_SPI_CLK_CFG);
 561         }
 562 
 563         /* Set Polarity and Phase */
 564         val = readl(regs + S3C64XX_SPI_CH_CFG);
 565         val &= ~(S3C64XX_SPI_CH_SLAVE |
 566                         S3C64XX_SPI_CPOL_L |
 567                         S3C64XX_SPI_CPHA_B);
 568 
 569         if (sdd->cur_mode & SPI_CPOL)
 570                 val |= S3C64XX_SPI_CPOL_L;
 571 
 572         if (sdd->cur_mode & SPI_CPHA)
 573                 val |= S3C64XX_SPI_CPHA_B;
 574 
 575         writel(val, regs + S3C64XX_SPI_CH_CFG);
 576 
 577         /* Set Channel & DMA Mode */
 578         val = readl(regs + S3C64XX_SPI_MODE_CFG);
 579         val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
 580                         | S3C64XX_SPI_MODE_CH_TSZ_MASK);
 581 
 582         switch (sdd->cur_bpw) {
 583         case 32:
 584                 val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
 585                 val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
 586                 break;
 587         case 16:
 588                 val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
 589                 val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
 590                 break;
 591         default:
 592                 val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
 593                 val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
 594                 break;
 595         }
 596 
 597         writel(val, regs + S3C64XX_SPI_MODE_CFG);
 598 
 599         if (sdd->port_conf->clk_from_cmu) {
 600                 /* The src_clk clock is divided internally by 2 */
 601                 clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
 602         } else {
 603                 /* Configure Clock */
 604                 val = readl(regs + S3C64XX_SPI_CLK_CFG);
 605                 val &= ~S3C64XX_SPI_PSR_MASK;
 606                 val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
 607                                 & S3C64XX_SPI_PSR_MASK);
 608                 writel(val, regs + S3C64XX_SPI_CLK_CFG);
 609 
 610                 /* Enable Clock */
 611                 val = readl(regs + S3C64XX_SPI_CLK_CFG);
 612                 val |= S3C64XX_SPI_ENCLK_ENABLE;
 613                 writel(val, regs + S3C64XX_SPI_CLK_CFG);
 614         }
 615 }
 616 
 617 #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
 618 
 619 static int s3c64xx_spi_prepare_message(struct spi_master *master,
 620                                        struct spi_message *msg)
 621 {
 622         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
 623         struct spi_device *spi = msg->spi;
 624         struct s3c64xx_spi_csinfo *cs = spi->controller_data;
 625 
 626         /* Configure feedback delay */
 627         writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
 628 
 629         return 0;
 630 }
 631 
 632 static int s3c64xx_spi_transfer_one(struct spi_master *master,
 633                                     struct spi_device *spi,
 634                                     struct spi_transfer *xfer)
 635 {
 636         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
 637         const unsigned int fifo_len = (FIFO_LVL_MASK(sdd) >> 1) + 1;
 638         const void *tx_buf = NULL;
 639         void *rx_buf = NULL;
 640         int target_len = 0, origin_len = 0;
 641         int use_dma = 0;
 642         int status;
 643         u32 speed;
 644         u8 bpw;
 645         unsigned long flags;
 646 
 647         reinit_completion(&sdd->xfer_completion);
 648 
 649         /* Only BPW and Speed may change across transfers */
 650         bpw = xfer->bits_per_word;
 651         speed = xfer->speed_hz;
 652 
 653         if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
 654                 sdd->cur_bpw = bpw;
 655                 sdd->cur_speed = speed;
 656                 sdd->cur_mode = spi->mode;
 657                 s3c64xx_spi_config(sdd);
 658         }
 659 
 660         if (!is_polling(sdd) && (xfer->len > fifo_len) &&
 661             sdd->rx_dma.ch && sdd->tx_dma.ch) {
 662                 use_dma = 1;
 663 
 664         } else if (is_polling(sdd) && xfer->len > fifo_len) {
 665                 tx_buf = xfer->tx_buf;
 666                 rx_buf = xfer->rx_buf;
 667                 origin_len = xfer->len;
 668 
 669                 target_len = xfer->len;
 670                 if (xfer->len > fifo_len)
 671                         xfer->len = fifo_len;
 672         }
 673 
 674         do {
 675                 spin_lock_irqsave(&sdd->lock, flags);
 676 
 677                 /* Pending only which is to be done */
 678                 sdd->state &= ~RXBUSY;
 679                 sdd->state &= ~TXBUSY;
 680 
 681                 s3c64xx_enable_datapath(sdd, xfer, use_dma);
 682 
 683                 /* Start the signals */
 684                 s3c64xx_spi_set_cs(spi, true);
 685 
 686                 spin_unlock_irqrestore(&sdd->lock, flags);
 687 
 688                 if (use_dma)
 689                         status = s3c64xx_wait_for_dma(sdd, xfer);
 690                 else
 691                         status = s3c64xx_wait_for_pio(sdd, xfer);
 692 
 693                 if (status) {
 694                         dev_err(&spi->dev,
 695                                 "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
 696                                 xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
 697                                 (sdd->state & RXBUSY) ? 'f' : 'p',
 698                                 (sdd->state & TXBUSY) ? 'f' : 'p',
 699                                 xfer->len);
 700 
 701                         if (use_dma) {
 702                                 if (xfer->tx_buf && (sdd->state & TXBUSY))
 703                                         dmaengine_terminate_all(sdd->tx_dma.ch);
 704                                 if (xfer->rx_buf && (sdd->state & RXBUSY))
 705                                         dmaengine_terminate_all(sdd->rx_dma.ch);
 706                         }
 707                 } else {
 708                         s3c64xx_flush_fifo(sdd);
 709                 }
 710                 if (target_len > 0) {
 711                         target_len -= xfer->len;
 712 
 713                         if (xfer->tx_buf)
 714                                 xfer->tx_buf += xfer->len;
 715 
 716                         if (xfer->rx_buf)
 717                                 xfer->rx_buf += xfer->len;
 718 
 719                         if (target_len > fifo_len)
 720                                 xfer->len = fifo_len;
 721                         else
 722                                 xfer->len = target_len;
 723                 }
 724         } while (target_len > 0);
 725 
 726         if (origin_len) {
 727                 /* Restore original xfer buffers and length */
 728                 xfer->tx_buf = tx_buf;
 729                 xfer->rx_buf = rx_buf;
 730                 xfer->len = origin_len;
 731         }
 732 
 733         return status;
 734 }
 735 
 736 static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
 737                                 struct spi_device *spi)
 738 {
 739         struct s3c64xx_spi_csinfo *cs;
 740         struct device_node *slave_np, *data_np = NULL;
 741         u32 fb_delay = 0;
 742 
 743         slave_np = spi->dev.of_node;
 744         if (!slave_np) {
 745                 dev_err(&spi->dev, "device node not found\n");
 746                 return ERR_PTR(-EINVAL);
 747         }
 748 
 749         data_np = of_get_child_by_name(slave_np, "controller-data");
 750         if (!data_np) {
 751                 dev_err(&spi->dev, "child node 'controller-data' not found\n");
 752                 return ERR_PTR(-EINVAL);
 753         }
 754 
 755         cs = kzalloc(sizeof(*cs), GFP_KERNEL);
 756         if (!cs) {
 757                 of_node_put(data_np);
 758                 return ERR_PTR(-ENOMEM);
 759         }
 760 
 761         of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
 762         cs->fb_delay = fb_delay;
 763         of_node_put(data_np);
 764         return cs;
 765 }
 766 
 767 /*
 768  * Here we only check the validity of requested configuration
 769  * and save the configuration in a local data-structure.
 770  * The controller is actually configured only just before we
 771  * get a message to transfer.
 772  */
 773 static int s3c64xx_spi_setup(struct spi_device *spi)
 774 {
 775         struct s3c64xx_spi_csinfo *cs = spi->controller_data;
 776         struct s3c64xx_spi_driver_data *sdd;
 777         int err;
 778 
 779         sdd = spi_master_get_devdata(spi->master);
 780         if (spi->dev.of_node) {
 781                 cs = s3c64xx_get_slave_ctrldata(spi);
 782                 spi->controller_data = cs;
 783         } else if (cs) {
 784                 /* On non-DT platforms the SPI core will set spi->cs_gpio
 785                  * to -ENOENT. The GPIO pin used to drive the chip select
 786                  * is defined by using platform data so spi->cs_gpio value
 787                  * has to be override to have the proper GPIO pin number.
 788                  */
 789                 spi->cs_gpio = cs->line;
 790         }
 791 
 792         if (IS_ERR_OR_NULL(cs)) {
 793                 dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
 794                 return -ENODEV;
 795         }
 796 
 797         if (!spi_get_ctldata(spi)) {
 798                 if (gpio_is_valid(spi->cs_gpio)) {
 799                         err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
 800                                                dev_name(&spi->dev));
 801                         if (err) {
 802                                 dev_err(&spi->dev,
 803                                         "Failed to get /CS gpio [%d]: %d\n",
 804                                         spi->cs_gpio, err);
 805                                 goto err_gpio_req;
 806                         }
 807                 }
 808 
 809                 spi_set_ctldata(spi, cs);
 810         }
 811 
 812         pm_runtime_get_sync(&sdd->pdev->dev);
 813 
 814         /* Check if we can provide the requested rate */
 815         if (!sdd->port_conf->clk_from_cmu) {
 816                 u32 psr, speed;
 817 
 818                 /* Max possible */
 819                 speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
 820 
 821                 if (spi->max_speed_hz > speed)
 822                         spi->max_speed_hz = speed;
 823 
 824                 psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
 825                 psr &= S3C64XX_SPI_PSR_MASK;
 826                 if (psr == S3C64XX_SPI_PSR_MASK)
 827                         psr--;
 828 
 829                 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
 830                 if (spi->max_speed_hz < speed) {
 831                         if (psr+1 < S3C64XX_SPI_PSR_MASK) {
 832                                 psr++;
 833                         } else {
 834                                 err = -EINVAL;
 835                                 goto setup_exit;
 836                         }
 837                 }
 838 
 839                 speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
 840                 if (spi->max_speed_hz >= speed) {
 841                         spi->max_speed_hz = speed;
 842                 } else {
 843                         dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
 844                                 spi->max_speed_hz);
 845                         err = -EINVAL;
 846                         goto setup_exit;
 847                 }
 848         }
 849 
 850         pm_runtime_mark_last_busy(&sdd->pdev->dev);
 851         pm_runtime_put_autosuspend(&sdd->pdev->dev);
 852         s3c64xx_spi_set_cs(spi, false);
 853 
 854         return 0;
 855 
 856 setup_exit:
 857         pm_runtime_mark_last_busy(&sdd->pdev->dev);
 858         pm_runtime_put_autosuspend(&sdd->pdev->dev);
 859         /* setup() returns with device de-selected */
 860         s3c64xx_spi_set_cs(spi, false);
 861 
 862         if (gpio_is_valid(spi->cs_gpio))
 863                 gpio_free(spi->cs_gpio);
 864         spi_set_ctldata(spi, NULL);
 865 
 866 err_gpio_req:
 867         if (spi->dev.of_node)
 868                 kfree(cs);
 869 
 870         return err;
 871 }
 872 
 873 static void s3c64xx_spi_cleanup(struct spi_device *spi)
 874 {
 875         struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
 876 
 877         if (gpio_is_valid(spi->cs_gpio)) {
 878                 gpio_free(spi->cs_gpio);
 879                 if (spi->dev.of_node)
 880                         kfree(cs);
 881                 else {
 882                         /* On non-DT platforms, the SPI core sets
 883                          * spi->cs_gpio to -ENOENT and .setup()
 884                          * overrides it with the GPIO pin value
 885                          * passed using platform data.
 886                          */
 887                         spi->cs_gpio = -ENOENT;
 888                 }
 889         }
 890 
 891         spi_set_ctldata(spi, NULL);
 892 }
 893 
 894 static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
 895 {
 896         struct s3c64xx_spi_driver_data *sdd = data;
 897         struct spi_master *spi = sdd->master;
 898         unsigned int val, clr = 0;
 899 
 900         val = readl(sdd->regs + S3C64XX_SPI_STATUS);
 901 
 902         if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
 903                 clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
 904                 dev_err(&spi->dev, "RX overrun\n");
 905         }
 906         if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
 907                 clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
 908                 dev_err(&spi->dev, "RX underrun\n");
 909         }
 910         if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
 911                 clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
 912                 dev_err(&spi->dev, "TX overrun\n");
 913         }
 914         if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
 915                 clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
 916                 dev_err(&spi->dev, "TX underrun\n");
 917         }
 918 
 919         /* Clear the pending irq by setting and then clearing it */
 920         writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
 921         writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
 922 
 923         return IRQ_HANDLED;
 924 }
 925 
 926 static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd)
 927 {
 928         struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
 929         void __iomem *regs = sdd->regs;
 930         unsigned int val;
 931 
 932         sdd->cur_speed = 0;
 933 
 934         if (sci->no_cs)
 935                 writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 936         else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
 937                 writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
 938 
 939         /* Disable Interrupts - we use Polling if not DMA mode */
 940         writel(0, regs + S3C64XX_SPI_INT_EN);
 941 
 942         if (!sdd->port_conf->clk_from_cmu)
 943                 writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
 944                                 regs + S3C64XX_SPI_CLK_CFG);
 945         writel(0, regs + S3C64XX_SPI_MODE_CFG);
 946         writel(0, regs + S3C64XX_SPI_PACKET_CNT);
 947 
 948         /* Clear any irq pending bits, should set and clear the bits */
 949         val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
 950                 S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
 951                 S3C64XX_SPI_PND_TX_OVERRUN_CLR |
 952                 S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
 953         writel(val, regs + S3C64XX_SPI_PENDING_CLR);
 954         writel(0, regs + S3C64XX_SPI_PENDING_CLR);
 955 
 956         writel(0, regs + S3C64XX_SPI_SWAP_CFG);
 957 
 958         val = readl(regs + S3C64XX_SPI_MODE_CFG);
 959         val &= ~S3C64XX_SPI_MODE_4BURST;
 960         val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
 961         val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
 962         writel(val, regs + S3C64XX_SPI_MODE_CFG);
 963 
 964         s3c64xx_flush_fifo(sdd);
 965 }
 966 
 967 #ifdef CONFIG_OF
 968 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
 969 {
 970         struct s3c64xx_spi_info *sci;
 971         u32 temp;
 972 
 973         sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
 974         if (!sci)
 975                 return ERR_PTR(-ENOMEM);
 976 
 977         if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
 978                 dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
 979                 sci->src_clk_nr = 0;
 980         } else {
 981                 sci->src_clk_nr = temp;
 982         }
 983 
 984         if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
 985                 dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
 986                 sci->num_cs = 1;
 987         } else {
 988                 sci->num_cs = temp;
 989         }
 990 
 991         sci->no_cs = of_property_read_bool(dev->of_node, "no-cs-readback");
 992 
 993         return sci;
 994 }
 995 #else
 996 static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
 997 {
 998         return dev_get_platdata(dev);
 999 }
1000 #endif
1001 
1002 static const struct of_device_id s3c64xx_spi_dt_match[];
1003 
1004 static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1005                                                 struct platform_device *pdev)
1006 {
1007 #ifdef CONFIG_OF
1008         if (pdev->dev.of_node) {
1009                 const struct of_device_id *match;
1010                 match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
1011                 return (struct s3c64xx_spi_port_config *)match->data;
1012         }
1013 #endif
1014         return (struct s3c64xx_spi_port_config *)
1015                          platform_get_device_id(pdev)->driver_data;
1016 }
1017 
1018 static int s3c64xx_spi_probe(struct platform_device *pdev)
1019 {
1020         struct resource *mem_res;
1021         struct s3c64xx_spi_driver_data *sdd;
1022         struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1023         struct spi_master *master;
1024         int ret, irq;
1025         char clk_name[16];
1026 
1027         if (!sci && pdev->dev.of_node) {
1028                 sci = s3c64xx_spi_parse_dt(&pdev->dev);
1029                 if (IS_ERR(sci))
1030                         return PTR_ERR(sci);
1031         }
1032 
1033         if (!sci) {
1034                 dev_err(&pdev->dev, "platform_data missing!\n");
1035                 return -ENODEV;
1036         }
1037 
1038         mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1039         if (mem_res == NULL) {
1040                 dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
1041                 return -ENXIO;
1042         }
1043 
1044         irq = platform_get_irq(pdev, 0);
1045         if (irq < 0) {
1046                 dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
1047                 return irq;
1048         }
1049 
1050         master = spi_alloc_master(&pdev->dev,
1051                                 sizeof(struct s3c64xx_spi_driver_data));
1052         if (master == NULL) {
1053                 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
1054                 return -ENOMEM;
1055         }
1056 
1057         platform_set_drvdata(pdev, master);
1058 
1059         sdd = spi_master_get_devdata(master);
1060         sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1061         sdd->master = master;
1062         sdd->cntrlr_info = sci;
1063         sdd->pdev = pdev;
1064         sdd->sfr_start = mem_res->start;
1065         if (pdev->dev.of_node) {
1066                 ret = of_alias_get_id(pdev->dev.of_node, "spi");
1067                 if (ret < 0) {
1068                         dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
1069                                 ret);
1070                         goto err_deref_master;
1071                 }
1072                 sdd->port_id = ret;
1073         } else {
1074                 sdd->port_id = pdev->id;
1075         }
1076 
1077         sdd->cur_bpw = 8;
1078 
1079         sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1080         sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1081 
1082         master->dev.of_node = pdev->dev.of_node;
1083         master->bus_num = sdd->port_id;
1084         master->setup = s3c64xx_spi_setup;
1085         master->cleanup = s3c64xx_spi_cleanup;
1086         master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1087         master->prepare_message = s3c64xx_spi_prepare_message;
1088         master->transfer_one = s3c64xx_spi_transfer_one;
1089         master->num_chipselect = sci->num_cs;
1090         master->dma_alignment = 8;
1091         master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1092                                         SPI_BPW_MASK(8);
1093         /* the spi->mode bits understood by this driver: */
1094         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1095         master->auto_runtime_pm = true;
1096         if (!is_polling(sdd))
1097                 master->can_dma = s3c64xx_spi_can_dma;
1098 
1099         sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
1100         if (IS_ERR(sdd->regs)) {
1101                 ret = PTR_ERR(sdd->regs);
1102                 goto err_deref_master;
1103         }
1104 
1105         if (sci->cfg_gpio && sci->cfg_gpio()) {
1106                 dev_err(&pdev->dev, "Unable to config gpio\n");
1107                 ret = -EBUSY;
1108                 goto err_deref_master;
1109         }
1110 
1111         /* Setup clocks */
1112         sdd->clk = devm_clk_get(&pdev->dev, "spi");
1113         if (IS_ERR(sdd->clk)) {
1114                 dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
1115                 ret = PTR_ERR(sdd->clk);
1116                 goto err_deref_master;
1117         }
1118 
1119         ret = clk_prepare_enable(sdd->clk);
1120         if (ret) {
1121                 dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
1122                 goto err_deref_master;
1123         }
1124 
1125         sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1126         sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
1127         if (IS_ERR(sdd->src_clk)) {
1128                 dev_err(&pdev->dev,
1129                         "Unable to acquire clock '%s'\n", clk_name);
1130                 ret = PTR_ERR(sdd->src_clk);
1131                 goto err_disable_clk;
1132         }
1133 
1134         ret = clk_prepare_enable(sdd->src_clk);
1135         if (ret) {
1136                 dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
1137                 goto err_disable_clk;
1138         }
1139 
1140         if (sdd->port_conf->clk_ioclk) {
1141                 sdd->ioclk = devm_clk_get(&pdev->dev, "spi_ioclk");
1142                 if (IS_ERR(sdd->ioclk)) {
1143                         dev_err(&pdev->dev, "Unable to acquire 'ioclk'\n");
1144                         ret = PTR_ERR(sdd->ioclk);
1145                         goto err_disable_src_clk;
1146                 }
1147 
1148                 ret = clk_prepare_enable(sdd->ioclk);
1149                 if (ret) {
1150                         dev_err(&pdev->dev, "Couldn't enable clock 'ioclk'\n");
1151                         goto err_disable_src_clk;
1152                 }
1153         }
1154 
1155         if (!is_polling(sdd)) {
1156                 /* Acquire DMA channels */
1157                 sdd->rx_dma.ch = dma_request_slave_channel_reason(&pdev->dev,
1158                                                                   "rx");
1159                 if (IS_ERR(sdd->rx_dma.ch)) {
1160                         dev_err(&pdev->dev, "Failed to get RX DMA channel\n");
1161                         ret = PTR_ERR(sdd->rx_dma.ch);
1162                         goto err_disable_io_clk;
1163                 }
1164                 sdd->tx_dma.ch = dma_request_slave_channel_reason(&pdev->dev,
1165                                                                   "tx");
1166                 if (IS_ERR(sdd->tx_dma.ch)) {
1167                         dev_err(&pdev->dev, "Failed to get TX DMA channel\n");
1168                         ret = PTR_ERR(sdd->tx_dma.ch);
1169                         goto err_release_rx_dma;
1170                 }
1171         }
1172 
1173         pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
1174         pm_runtime_use_autosuspend(&pdev->dev);
1175         pm_runtime_set_active(&pdev->dev);
1176         pm_runtime_enable(&pdev->dev);
1177         pm_runtime_get_sync(&pdev->dev);
1178 
1179         /* Setup Deufult Mode */
1180         s3c64xx_spi_hwinit(sdd);
1181 
1182         spin_lock_init(&sdd->lock);
1183         init_completion(&sdd->xfer_completion);
1184 
1185         ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1186                                 "spi-s3c64xx", sdd);
1187         if (ret != 0) {
1188                 dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1189                         irq, ret);
1190                 goto err_pm_put;
1191         }
1192 
1193         writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1194                S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1195                sdd->regs + S3C64XX_SPI_INT_EN);
1196 
1197         ret = devm_spi_register_master(&pdev->dev, master);
1198         if (ret != 0) {
1199                 dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
1200                 goto err_pm_put;
1201         }
1202 
1203         dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
1204                                         sdd->port_id, master->num_chipselect);
1205         dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\n",
1206                                         mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1);
1207 
1208         pm_runtime_mark_last_busy(&pdev->dev);
1209         pm_runtime_put_autosuspend(&pdev->dev);
1210 
1211         return 0;
1212 
1213 err_pm_put:
1214         pm_runtime_put_noidle(&pdev->dev);
1215         pm_runtime_disable(&pdev->dev);
1216         pm_runtime_set_suspended(&pdev->dev);
1217 
1218         if (!is_polling(sdd))
1219                 dma_release_channel(sdd->tx_dma.ch);
1220 err_release_rx_dma:
1221         if (!is_polling(sdd))
1222                 dma_release_channel(sdd->rx_dma.ch);
1223 err_disable_io_clk:
1224         clk_disable_unprepare(sdd->ioclk);
1225 err_disable_src_clk:
1226         clk_disable_unprepare(sdd->src_clk);
1227 err_disable_clk:
1228         clk_disable_unprepare(sdd->clk);
1229 err_deref_master:
1230         spi_master_put(master);
1231 
1232         return ret;
1233 }
1234 
1235 static int s3c64xx_spi_remove(struct platform_device *pdev)
1236 {
1237         struct spi_master *master = platform_get_drvdata(pdev);
1238         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1239 
1240         pm_runtime_get_sync(&pdev->dev);
1241 
1242         writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1243 
1244         if (!is_polling(sdd)) {
1245                 dma_release_channel(sdd->rx_dma.ch);
1246                 dma_release_channel(sdd->tx_dma.ch);
1247         }
1248 
1249         clk_disable_unprepare(sdd->ioclk);
1250 
1251         clk_disable_unprepare(sdd->src_clk);
1252 
1253         clk_disable_unprepare(sdd->clk);
1254 
1255         pm_runtime_put_noidle(&pdev->dev);
1256         pm_runtime_disable(&pdev->dev);
1257         pm_runtime_set_suspended(&pdev->dev);
1258 
1259         return 0;
1260 }
1261 
1262 #ifdef CONFIG_PM_SLEEP
1263 static int s3c64xx_spi_suspend(struct device *dev)
1264 {
1265         struct spi_master *master = dev_get_drvdata(dev);
1266         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1267 
1268         int ret = spi_master_suspend(master);
1269         if (ret)
1270                 return ret;
1271 
1272         ret = pm_runtime_force_suspend(dev);
1273         if (ret < 0)
1274                 return ret;
1275 
1276         sdd->cur_speed = 0; /* Output Clock is stopped */
1277 
1278         return 0;
1279 }
1280 
1281 static int s3c64xx_spi_resume(struct device *dev)
1282 {
1283         struct spi_master *master = dev_get_drvdata(dev);
1284         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1285         struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1286         int ret;
1287 
1288         if (sci->cfg_gpio)
1289                 sci->cfg_gpio();
1290 
1291         ret = pm_runtime_force_resume(dev);
1292         if (ret < 0)
1293                 return ret;
1294 
1295         return spi_master_resume(master);
1296 }
1297 #endif /* CONFIG_PM_SLEEP */
1298 
1299 #ifdef CONFIG_PM
1300 static int s3c64xx_spi_runtime_suspend(struct device *dev)
1301 {
1302         struct spi_master *master = dev_get_drvdata(dev);
1303         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1304 
1305         clk_disable_unprepare(sdd->clk);
1306         clk_disable_unprepare(sdd->src_clk);
1307         clk_disable_unprepare(sdd->ioclk);
1308 
1309         return 0;
1310 }
1311 
1312 static int s3c64xx_spi_runtime_resume(struct device *dev)
1313 {
1314         struct spi_master *master = dev_get_drvdata(dev);
1315         struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
1316         int ret;
1317 
1318         if (sdd->port_conf->clk_ioclk) {
1319                 ret = clk_prepare_enable(sdd->ioclk);
1320                 if (ret != 0)
1321                         return ret;
1322         }
1323 
1324         ret = clk_prepare_enable(sdd->src_clk);
1325         if (ret != 0)
1326                 goto err_disable_ioclk;
1327 
1328         ret = clk_prepare_enable(sdd->clk);
1329         if (ret != 0)
1330                 goto err_disable_src_clk;
1331 
1332         s3c64xx_spi_hwinit(sdd);
1333 
1334         return 0;
1335 
1336 err_disable_src_clk:
1337         clk_disable_unprepare(sdd->src_clk);
1338 err_disable_ioclk:
1339         clk_disable_unprepare(sdd->ioclk);
1340 
1341         return ret;
1342 }
1343 #endif /* CONFIG_PM */
1344 
1345 static const struct dev_pm_ops s3c64xx_spi_pm = {
1346         SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1347         SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1348                            s3c64xx_spi_runtime_resume, NULL)
1349 };
1350 
1351 static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1352         .fifo_lvl_mask  = { 0x7f },
1353         .rx_lvl_offset  = 13,
1354         .tx_st_done     = 21,
1355         .high_speed     = true,
1356 };
1357 
1358 static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1359         .fifo_lvl_mask  = { 0x7f, 0x7F },
1360         .rx_lvl_offset  = 13,
1361         .tx_st_done     = 21,
1362 };
1363 
1364 static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1365         .fifo_lvl_mask  = { 0x1ff, 0x7F },
1366         .rx_lvl_offset  = 15,
1367         .tx_st_done     = 25,
1368         .high_speed     = true,
1369 };
1370 
1371 static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1372         .fifo_lvl_mask  = { 0x1ff, 0x7F, 0x7F },
1373         .rx_lvl_offset  = 15,
1374         .tx_st_done     = 25,
1375         .high_speed     = true,
1376         .clk_from_cmu   = true,
1377 };
1378 
1379 static struct s3c64xx_spi_port_config exynos7_spi_port_config = {
1380         .fifo_lvl_mask  = { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
1381         .rx_lvl_offset  = 15,
1382         .tx_st_done     = 25,
1383         .high_speed     = true,
1384         .clk_from_cmu   = true,
1385         .quirks         = S3C64XX_SPI_QUIRK_CS_AUTO,
1386 };
1387 
1388 static struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
1389         .fifo_lvl_mask  = { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
1390         .rx_lvl_offset  = 15,
1391         .tx_st_done     = 25,
1392         .high_speed     = true,
1393         .clk_from_cmu   = true,
1394         .clk_ioclk      = true,
1395         .quirks         = S3C64XX_SPI_QUIRK_CS_AUTO,
1396 };
1397 
1398 static const struct platform_device_id s3c64xx_spi_driver_ids[] = {
1399         {
1400                 .name           = "s3c2443-spi",
1401                 .driver_data    = (kernel_ulong_t)&s3c2443_spi_port_config,
1402         }, {
1403                 .name           = "s3c6410-spi",
1404                 .driver_data    = (kernel_ulong_t)&s3c6410_spi_port_config,
1405         },
1406         { },
1407 };
1408 
1409 static const struct of_device_id s3c64xx_spi_dt_match[] = {
1410         { .compatible = "samsung,s3c2443-spi",
1411                         .data = (void *)&s3c2443_spi_port_config,
1412         },
1413         { .compatible = "samsung,s3c6410-spi",
1414                         .data = (void *)&s3c6410_spi_port_config,
1415         },
1416         { .compatible = "samsung,s5pv210-spi",
1417                         .data = (void *)&s5pv210_spi_port_config,
1418         },
1419         { .compatible = "samsung,exynos4210-spi",
1420                         .data = (void *)&exynos4_spi_port_config,
1421         },
1422         { .compatible = "samsung,exynos7-spi",
1423                         .data = (void *)&exynos7_spi_port_config,
1424         },
1425         { .compatible = "samsung,exynos5433-spi",
1426                         .data = (void *)&exynos5433_spi_port_config,
1427         },
1428         { },
1429 };
1430 MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1431 
1432 static struct platform_driver s3c64xx_spi_driver = {
1433         .driver = {
1434                 .name   = "s3c64xx-spi",
1435                 .pm = &s3c64xx_spi_pm,
1436                 .of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1437         },
1438         .probe = s3c64xx_spi_probe,
1439         .remove = s3c64xx_spi_remove,
1440         .id_table = s3c64xx_spi_driver_ids,
1441 };
1442 MODULE_ALIAS("platform:s3c64xx-spi");
1443 
1444 module_platform_driver(s3c64xx_spi_driver);
1445 
1446 MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1447 MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1448 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/spi/spi-s3c64xx.c

DEFINITIONS
