linux/drivers/spi/spi-adi-v3.c
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   1/*
   2 * Analog Devices SPI3 controller driver
   3 *
   4 * Copyright (c) 2014 Analog Devices Inc.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   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
  16#include <linux/clk.h>
  17#include <linux/delay.h>
  18#include <linux/device.h>
  19#include <linux/dma-mapping.h>
  20#include <linux/errno.h>
  21#include <linux/gpio.h>
  22#include <linux/init.h>
  23#include <linux/interrupt.h>
  24#include <linux/io.h>
  25#include <linux/ioport.h>
  26#include <linux/module.h>
  27#include <linux/platform_device.h>
  28#include <linux/slab.h>
  29#include <linux/spi/spi.h>
  30#include <linux/spi/adi_spi3.h>
  31#include <linux/types.h>
  32
  33#include <asm/dma.h>
  34#include <asm/portmux.h>
  35
  36enum adi_spi_state {
  37        START_STATE,
  38        RUNNING_STATE,
  39        DONE_STATE,
  40        ERROR_STATE
  41};
  42
  43struct adi_spi_master;
  44
  45struct adi_spi_transfer_ops {
  46        void (*write) (struct adi_spi_master *);
  47        void (*read) (struct adi_spi_master *);
  48        void (*duplex) (struct adi_spi_master *);
  49};
  50
  51/* runtime info for spi master */
  52struct adi_spi_master {
  53        /* SPI framework hookup */
  54        struct spi_master *master;
  55
  56        /* Regs base of SPI controller */
  57        struct adi_spi_regs __iomem *regs;
  58
  59        /* Pin request list */
  60        u16 *pin_req;
  61
  62        /* Message Transfer pump */
  63        struct tasklet_struct pump_transfers;
  64
  65        /* Current message transfer state info */
  66        struct spi_message *cur_msg;
  67        struct spi_transfer *cur_transfer;
  68        struct adi_spi_device *cur_chip;
  69        unsigned transfer_len;
  70
  71        /* transfer buffer */
  72        void *tx;
  73        void *tx_end;
  74        void *rx;
  75        void *rx_end;
  76
  77        /* dma info */
  78        unsigned int tx_dma;
  79        unsigned int rx_dma;
  80        dma_addr_t tx_dma_addr;
  81        dma_addr_t rx_dma_addr;
  82        unsigned long dummy_buffer; /* used in unidirectional transfer */
  83        unsigned long tx_dma_size;
  84        unsigned long rx_dma_size;
  85        int tx_num;
  86        int rx_num;
  87
  88        /* store register value for suspend/resume */
  89        u32 control;
  90        u32 ssel;
  91
  92        unsigned long sclk;
  93        enum adi_spi_state state;
  94
  95        const struct adi_spi_transfer_ops *ops;
  96};
  97
  98struct adi_spi_device {
  99        u32 control;
 100        u32 clock;
 101        u32 ssel;
 102
 103        u8 cs;
 104        u16 cs_chg_udelay; /* Some devices require > 255usec delay */
 105        u32 cs_gpio;
 106        u32 tx_dummy_val; /* tx value for rx only transfer */
 107        bool enable_dma;
 108        const struct adi_spi_transfer_ops *ops;
 109};
 110
 111static void adi_spi_enable(struct adi_spi_master *drv_data)
 112{
 113        u32 ctl;
 114
 115        ctl = ioread32(&drv_data->regs->control);
 116        ctl |= SPI_CTL_EN;
 117        iowrite32(ctl, &drv_data->regs->control);
 118}
 119
 120static void adi_spi_disable(struct adi_spi_master *drv_data)
 121{
 122        u32 ctl;
 123
 124        ctl = ioread32(&drv_data->regs->control);
 125        ctl &= ~SPI_CTL_EN;
 126        iowrite32(ctl, &drv_data->regs->control);
 127}
 128
 129/* Caculate the SPI_CLOCK register value based on input HZ */
 130static u32 hz_to_spi_clock(u32 sclk, u32 speed_hz)
 131{
 132        u32 spi_clock = sclk / speed_hz;
 133
 134        if (spi_clock)
 135                spi_clock--;
 136        return spi_clock;
 137}
 138
 139static int adi_spi_flush(struct adi_spi_master *drv_data)
 140{
 141        unsigned long limit = loops_per_jiffy << 1;
 142
 143        /* wait for stop and clear stat */
 144        while (!(ioread32(&drv_data->regs->status) & SPI_STAT_SPIF) && --limit)
 145                cpu_relax();
 146
 147        iowrite32(0xFFFFFFFF, &drv_data->regs->status);
 148
 149        return limit;
 150}
 151
 152/* Chip select operation functions for cs_change flag */
 153static void adi_spi_cs_active(struct adi_spi_master *drv_data, struct adi_spi_device *chip)
 154{
 155        if (likely(chip->cs < MAX_CTRL_CS)) {
 156                u32 reg;
 157                reg = ioread32(&drv_data->regs->ssel);
 158                reg &= ~chip->ssel;
 159                iowrite32(reg, &drv_data->regs->ssel);
 160        } else {
 161                gpio_set_value(chip->cs_gpio, 0);
 162        }
 163}
 164
 165static void adi_spi_cs_deactive(struct adi_spi_master *drv_data,
 166                                struct adi_spi_device *chip)
 167{
 168        if (likely(chip->cs < MAX_CTRL_CS)) {
 169                u32 reg;
 170                reg = ioread32(&drv_data->regs->ssel);
 171                reg |= chip->ssel;
 172                iowrite32(reg, &drv_data->regs->ssel);
 173        } else {
 174                gpio_set_value(chip->cs_gpio, 1);
 175        }
 176
 177        /* Move delay here for consistency */
 178        if (chip->cs_chg_udelay)
 179                udelay(chip->cs_chg_udelay);
 180}
 181
 182/* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */
 183static inline void adi_spi_cs_enable(struct adi_spi_master *drv_data,
 184                                        struct adi_spi_device *chip)
 185{
 186        if (chip->cs < MAX_CTRL_CS) {
 187                u32 reg;
 188                reg = ioread32(&drv_data->regs->ssel);
 189                reg |= chip->ssel >> 8;
 190                iowrite32(reg, &drv_data->regs->ssel);
 191        }
 192}
 193
 194static inline void adi_spi_cs_disable(struct adi_spi_master *drv_data,
 195                                        struct adi_spi_device *chip)
 196{
 197        if (chip->cs < MAX_CTRL_CS) {
 198                u32 reg;
 199                reg = ioread32(&drv_data->regs->ssel);
 200                reg &= ~(chip->ssel >> 8);
 201                iowrite32(reg, &drv_data->regs->ssel);
 202        }
 203}
 204
 205/* stop controller and re-config current chip*/
 206static void adi_spi_restore_state(struct adi_spi_master *drv_data)
 207{
 208        struct adi_spi_device *chip = drv_data->cur_chip;
 209
 210        /* Clear status and disable clock */
 211        iowrite32(0xFFFFFFFF, &drv_data->regs->status);
 212        iowrite32(0x0, &drv_data->regs->rx_control);
 213        iowrite32(0x0, &drv_data->regs->tx_control);
 214        adi_spi_disable(drv_data);
 215
 216        /* Load the registers */
 217        iowrite32(chip->control, &drv_data->regs->control);
 218        iowrite32(chip->clock, &drv_data->regs->clock);
 219
 220        adi_spi_enable(drv_data);
 221        drv_data->tx_num = drv_data->rx_num = 0;
 222        /* we always choose tx transfer initiate */
 223        iowrite32(SPI_RXCTL_REN, &drv_data->regs->rx_control);
 224        iowrite32(SPI_TXCTL_TEN | SPI_TXCTL_TTI, &drv_data->regs->tx_control);
 225        adi_spi_cs_active(drv_data, chip);
 226}
 227
 228/* discard invalid rx data and empty rfifo */
 229static inline void dummy_read(struct adi_spi_master *drv_data)
 230{
 231        while (!(ioread32(&drv_data->regs->status) & SPI_STAT_RFE))
 232                ioread32(&drv_data->regs->rfifo);
 233}
 234
 235static void adi_spi_u8_write(struct adi_spi_master *drv_data)
 236{
 237        dummy_read(drv_data);
 238        while (drv_data->tx < drv_data->tx_end) {
 239                iowrite32(*(u8 *)(drv_data->tx++), &drv_data->regs->tfifo);
 240                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 241                        cpu_relax();
 242                ioread32(&drv_data->regs->rfifo);
 243        }
 244}
 245
 246static void adi_spi_u8_read(struct adi_spi_master *drv_data)
 247{
 248        u32 tx_val = drv_data->cur_chip->tx_dummy_val;
 249
 250        dummy_read(drv_data);
 251        while (drv_data->rx < drv_data->rx_end) {
 252                iowrite32(tx_val, &drv_data->regs->tfifo);
 253                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 254                        cpu_relax();
 255                *(u8 *)(drv_data->rx++) = ioread32(&drv_data->regs->rfifo);
 256        }
 257}
 258
 259static void adi_spi_u8_duplex(struct adi_spi_master *drv_data)
 260{
 261        dummy_read(drv_data);
 262        while (drv_data->rx < drv_data->rx_end) {
 263                iowrite32(*(u8 *)(drv_data->tx++), &drv_data->regs->tfifo);
 264                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 265                        cpu_relax();
 266                *(u8 *)(drv_data->rx++) = ioread32(&drv_data->regs->rfifo);
 267        }
 268}
 269
 270static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u8 = {
 271        .write  = adi_spi_u8_write,
 272        .read   = adi_spi_u8_read,
 273        .duplex = adi_spi_u8_duplex,
 274};
 275
 276static void adi_spi_u16_write(struct adi_spi_master *drv_data)
 277{
 278        dummy_read(drv_data);
 279        while (drv_data->tx < drv_data->tx_end) {
 280                iowrite32(*(u16 *)drv_data->tx, &drv_data->regs->tfifo);
 281                drv_data->tx += 2;
 282                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 283                        cpu_relax();
 284                ioread32(&drv_data->regs->rfifo);
 285        }
 286}
 287
 288static void adi_spi_u16_read(struct adi_spi_master *drv_data)
 289{
 290        u32 tx_val = drv_data->cur_chip->tx_dummy_val;
 291
 292        dummy_read(drv_data);
 293        while (drv_data->rx < drv_data->rx_end) {
 294                iowrite32(tx_val, &drv_data->regs->tfifo);
 295                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 296                        cpu_relax();
 297                *(u16 *)drv_data->rx = ioread32(&drv_data->regs->rfifo);
 298                drv_data->rx += 2;
 299        }
 300}
 301
 302static void adi_spi_u16_duplex(struct adi_spi_master *drv_data)
 303{
 304        dummy_read(drv_data);
 305        while (drv_data->rx < drv_data->rx_end) {
 306                iowrite32(*(u16 *)drv_data->tx, &drv_data->regs->tfifo);
 307                drv_data->tx += 2;
 308                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 309                        cpu_relax();
 310                *(u16 *)drv_data->rx = ioread32(&drv_data->regs->rfifo);
 311                drv_data->rx += 2;
 312        }
 313}
 314
 315static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u16 = {
 316        .write  = adi_spi_u16_write,
 317        .read   = adi_spi_u16_read,
 318        .duplex = adi_spi_u16_duplex,
 319};
 320
 321static void adi_spi_u32_write(struct adi_spi_master *drv_data)
 322{
 323        dummy_read(drv_data);
 324        while (drv_data->tx < drv_data->tx_end) {
 325                iowrite32(*(u32 *)drv_data->tx, &drv_data->regs->tfifo);
 326                drv_data->tx += 4;
 327                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 328                        cpu_relax();
 329                ioread32(&drv_data->regs->rfifo);
 330        }
 331}
 332
 333static void adi_spi_u32_read(struct adi_spi_master *drv_data)
 334{
 335        u32 tx_val = drv_data->cur_chip->tx_dummy_val;
 336
 337        dummy_read(drv_data);
 338        while (drv_data->rx < drv_data->rx_end) {
 339                iowrite32(tx_val, &drv_data->regs->tfifo);
 340                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 341                        cpu_relax();
 342                *(u32 *)drv_data->rx = ioread32(&drv_data->regs->rfifo);
 343                drv_data->rx += 4;
 344        }
 345}
 346
 347static void adi_spi_u32_duplex(struct adi_spi_master *drv_data)
 348{
 349        dummy_read(drv_data);
 350        while (drv_data->rx < drv_data->rx_end) {
 351                iowrite32(*(u32 *)drv_data->tx, &drv_data->regs->tfifo);
 352                drv_data->tx += 4;
 353                while (ioread32(&drv_data->regs->status) & SPI_STAT_RFE)
 354                        cpu_relax();
 355                *(u32 *)drv_data->rx = ioread32(&drv_data->regs->rfifo);
 356                drv_data->rx += 4;
 357        }
 358}
 359
 360static const struct adi_spi_transfer_ops adi_spi_transfer_ops_u32 = {
 361        .write  = adi_spi_u32_write,
 362        .read   = adi_spi_u32_read,
 363        .duplex = adi_spi_u32_duplex,
 364};
 365
 366
 367/* test if there is more transfer to be done */
 368static void adi_spi_next_transfer(struct adi_spi_master *drv)
 369{
 370        struct spi_message *msg = drv->cur_msg;
 371        struct spi_transfer *t = drv->cur_transfer;
 372
 373        /* Move to next transfer */
 374        if (t->transfer_list.next != &msg->transfers) {
 375                drv->cur_transfer = list_entry(t->transfer_list.next,
 376                               struct spi_transfer, transfer_list);
 377                drv->state = RUNNING_STATE;
 378        } else {
 379                drv->state = DONE_STATE;
 380                drv->cur_transfer = NULL;
 381        }
 382}
 383
 384static void adi_spi_giveback(struct adi_spi_master *drv_data)
 385{
 386        struct adi_spi_device *chip = drv_data->cur_chip;
 387
 388        adi_spi_cs_deactive(drv_data, chip);
 389        spi_finalize_current_message(drv_data->master);
 390}
 391
 392static int adi_spi_setup_transfer(struct adi_spi_master *drv)
 393{
 394        struct spi_transfer *t = drv->cur_transfer;
 395        u32 cr, cr_width;
 396
 397        if (t->tx_buf) {
 398                drv->tx = (void *)t->tx_buf;
 399                drv->tx_end = drv->tx + t->len;
 400        } else {
 401                drv->tx = NULL;
 402        }
 403
 404        if (t->rx_buf) {
 405                drv->rx = t->rx_buf;
 406                drv->rx_end = drv->rx + t->len;
 407        } else {
 408                drv->rx = NULL;
 409        }
 410
 411        drv->transfer_len = t->len;
 412
 413        /* bits per word setup */
 414        switch (t->bits_per_word) {
 415        case 8:
 416                cr_width = SPI_CTL_SIZE08;
 417                drv->ops = &adi_spi_transfer_ops_u8;
 418                break;
 419        case 16:
 420                cr_width = SPI_CTL_SIZE16;
 421                drv->ops = &adi_spi_transfer_ops_u16;
 422                break;
 423        case 32:
 424                cr_width = SPI_CTL_SIZE32;
 425                drv->ops = &adi_spi_transfer_ops_u32;
 426                break;
 427        default:
 428                return -EINVAL;
 429        }
 430        cr = ioread32(&drv->regs->control) & ~SPI_CTL_SIZE;
 431        cr |= cr_width;
 432        iowrite32(cr, &drv->regs->control);
 433
 434        /* speed setup */
 435        iowrite32(hz_to_spi_clock(drv->sclk, t->speed_hz), &drv->regs->clock);
 436        return 0;
 437}
 438
 439static int adi_spi_dma_xfer(struct adi_spi_master *drv_data)
 440{
 441        struct spi_transfer *t = drv_data->cur_transfer;
 442        struct spi_message *msg = drv_data->cur_msg;
 443        struct adi_spi_device *chip = drv_data->cur_chip;
 444        u32 dma_config;
 445        unsigned long word_count, word_size;
 446        void *tx_buf, *rx_buf;
 447
 448        switch (t->bits_per_word) {
 449        case 8:
 450                dma_config = WDSIZE_8 | PSIZE_8;
 451                word_count = drv_data->transfer_len;
 452                word_size = 1;
 453                break;
 454        case 16:
 455                dma_config = WDSIZE_16 | PSIZE_16;
 456                word_count = drv_data->transfer_len / 2;
 457                word_size = 2;
 458                break;
 459        default:
 460                dma_config = WDSIZE_32 | PSIZE_32;
 461                word_count = drv_data->transfer_len / 4;
 462                word_size = 4;
 463                break;
 464        }
 465
 466        if (!drv_data->rx) {
 467                tx_buf = drv_data->tx;
 468                rx_buf = &drv_data->dummy_buffer;
 469                drv_data->tx_dma_size = drv_data->transfer_len;
 470                drv_data->rx_dma_size = sizeof(drv_data->dummy_buffer);
 471                set_dma_x_modify(drv_data->tx_dma, word_size);
 472                set_dma_x_modify(drv_data->rx_dma, 0);
 473        } else if (!drv_data->tx) {
 474                drv_data->dummy_buffer = chip->tx_dummy_val;
 475                tx_buf = &drv_data->dummy_buffer;
 476                rx_buf = drv_data->rx;
 477                drv_data->tx_dma_size = sizeof(drv_data->dummy_buffer);
 478                drv_data->rx_dma_size = drv_data->transfer_len;
 479                set_dma_x_modify(drv_data->tx_dma, 0);
 480                set_dma_x_modify(drv_data->rx_dma, word_size);
 481        } else {
 482                tx_buf = drv_data->tx;
 483                rx_buf = drv_data->rx;
 484                drv_data->tx_dma_size = drv_data->rx_dma_size
 485                                        = drv_data->transfer_len;
 486                set_dma_x_modify(drv_data->tx_dma, word_size);
 487                set_dma_x_modify(drv_data->rx_dma, word_size);
 488        }
 489
 490        drv_data->tx_dma_addr = dma_map_single(&msg->spi->dev,
 491                                (void *)tx_buf,
 492                                drv_data->tx_dma_size,
 493                                DMA_TO_DEVICE);
 494        if (dma_mapping_error(&msg->spi->dev,
 495                                drv_data->tx_dma_addr))
 496                return -ENOMEM;
 497
 498        drv_data->rx_dma_addr = dma_map_single(&msg->spi->dev,
 499                                (void *)rx_buf,
 500                                drv_data->rx_dma_size,
 501                                DMA_FROM_DEVICE);
 502        if (dma_mapping_error(&msg->spi->dev,
 503                                drv_data->rx_dma_addr)) {
 504                dma_unmap_single(&msg->spi->dev,
 505                                drv_data->tx_dma_addr,
 506                                drv_data->tx_dma_size,
 507                                DMA_TO_DEVICE);
 508                return -ENOMEM;
 509        }
 510
 511        dummy_read(drv_data);
 512        set_dma_x_count(drv_data->tx_dma, word_count);
 513        set_dma_x_count(drv_data->rx_dma, word_count);
 514        set_dma_start_addr(drv_data->tx_dma, drv_data->tx_dma_addr);
 515        set_dma_start_addr(drv_data->rx_dma, drv_data->rx_dma_addr);
 516        dma_config |= DMAFLOW_STOP | RESTART | DI_EN;
 517        set_dma_config(drv_data->tx_dma, dma_config);
 518        set_dma_config(drv_data->rx_dma, dma_config | WNR);
 519        enable_dma(drv_data->tx_dma);
 520        enable_dma(drv_data->rx_dma);
 521
 522        iowrite32(SPI_RXCTL_REN | SPI_RXCTL_RDR_NE,
 523                        &drv_data->regs->rx_control);
 524        iowrite32(SPI_TXCTL_TEN | SPI_TXCTL_TTI | SPI_TXCTL_TDR_NF,
 525                        &drv_data->regs->tx_control);
 526
 527        return 0;
 528}
 529
 530static int adi_spi_pio_xfer(struct adi_spi_master *drv_data)
 531{
 532        struct spi_message *msg = drv_data->cur_msg;
 533
 534        if (!drv_data->rx) {
 535                /* write only half duplex */
 536                drv_data->ops->write(drv_data);
 537                if (drv_data->tx != drv_data->tx_end)
 538                        return -EIO;
 539        } else if (!drv_data->tx) {
 540                /* read only half duplex */
 541                drv_data->ops->read(drv_data);
 542                if (drv_data->rx != drv_data->rx_end)
 543                        return -EIO;
 544        } else {
 545                /* full duplex mode */
 546                drv_data->ops->duplex(drv_data);
 547                if (drv_data->tx != drv_data->tx_end)
 548                        return -EIO;
 549        }
 550
 551        if (!adi_spi_flush(drv_data))
 552                return -EIO;
 553        msg->actual_length += drv_data->transfer_len;
 554        tasklet_schedule(&drv_data->pump_transfers);
 555        return 0;
 556}
 557
 558static void adi_spi_pump_transfers(unsigned long data)
 559{
 560        struct adi_spi_master *drv_data = (struct adi_spi_master *)data;
 561        struct spi_message *msg = NULL;
 562        struct spi_transfer *t = NULL;
 563        struct adi_spi_device *chip = NULL;
 564        int ret;
 565
 566        /* Get current state information */
 567        msg = drv_data->cur_msg;
 568        t = drv_data->cur_transfer;
 569        chip = drv_data->cur_chip;
 570
 571        /* Handle for abort */
 572        if (drv_data->state == ERROR_STATE) {
 573                msg->status = -EIO;
 574                adi_spi_giveback(drv_data);
 575                return;
 576        }
 577
 578        if (drv_data->state == RUNNING_STATE) {
 579                if (t->delay_usecs)
 580                        udelay(t->delay_usecs);
 581                if (t->cs_change)
 582                        adi_spi_cs_deactive(drv_data, chip);
 583                adi_spi_next_transfer(drv_data);
 584                t = drv_data->cur_transfer;
 585        }
 586        /* Handle end of message */
 587        if (drv_data->state == DONE_STATE) {
 588                msg->status = 0;
 589                adi_spi_giveback(drv_data);
 590                return;
 591        }
 592
 593        if ((t->len == 0) || (t->tx_buf == NULL && t->rx_buf == NULL)) {
 594                /* Schedule next transfer tasklet */
 595                tasklet_schedule(&drv_data->pump_transfers);
 596                return;
 597        }
 598
 599        ret = adi_spi_setup_transfer(drv_data);
 600        if (ret) {
 601                msg->status = ret;
 602                adi_spi_giveback(drv_data);
 603        }
 604
 605        iowrite32(0xFFFFFFFF, &drv_data->regs->status);
 606        adi_spi_cs_active(drv_data, chip);
 607        drv_data->state = RUNNING_STATE;
 608
 609        if (chip->enable_dma)
 610                ret = adi_spi_dma_xfer(drv_data);
 611        else
 612                ret = adi_spi_pio_xfer(drv_data);
 613        if (ret) {
 614                msg->status = ret;
 615                adi_spi_giveback(drv_data);
 616        }
 617}
 618
 619static int adi_spi_transfer_one_message(struct spi_master *master,
 620                                        struct spi_message *m)
 621{
 622        struct adi_spi_master *drv_data = spi_master_get_devdata(master);
 623
 624        drv_data->cur_msg = m;
 625        drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
 626        adi_spi_restore_state(drv_data);
 627
 628        drv_data->state = START_STATE;
 629        drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
 630                                            struct spi_transfer, transfer_list);
 631
 632        tasklet_schedule(&drv_data->pump_transfers);
 633        return 0;
 634}
 635
 636#define MAX_SPI_SSEL    7
 637
 638static const u16 ssel[][MAX_SPI_SSEL] = {
 639        {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3,
 640        P_SPI0_SSEL4, P_SPI0_SSEL5,
 641        P_SPI0_SSEL6, P_SPI0_SSEL7},
 642
 643        {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3,
 644        P_SPI1_SSEL4, P_SPI1_SSEL5,
 645        P_SPI1_SSEL6, P_SPI1_SSEL7},
 646
 647        {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3,
 648        P_SPI2_SSEL4, P_SPI2_SSEL5,
 649        P_SPI2_SSEL6, P_SPI2_SSEL7},
 650};
 651
 652static int adi_spi_setup(struct spi_device *spi)
 653{
 654        struct adi_spi_master *drv_data = spi_master_get_devdata(spi->master);
 655        struct adi_spi_device *chip = spi_get_ctldata(spi);
 656        u32 ctl_reg = SPI_CTL_ODM | SPI_CTL_PSSE;
 657        int ret = -EINVAL;
 658
 659        if (!chip) {
 660                struct adi_spi3_chip *chip_info = spi->controller_data;
 661
 662                chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 663                if (!chip) {
 664                        dev_err(&spi->dev, "can not allocate chip data\n");
 665                        return -ENOMEM;
 666                }
 667                if (chip_info) {
 668                        if (chip_info->control & ~ctl_reg) {
 669                                dev_err(&spi->dev,
 670                                        "do not set bits that the SPI framework manages\n");
 671                                goto error;
 672                        }
 673                        chip->control = chip_info->control;
 674                        chip->cs_chg_udelay = chip_info->cs_chg_udelay;
 675                        chip->tx_dummy_val = chip_info->tx_dummy_val;
 676                        chip->enable_dma = chip_info->enable_dma;
 677                }
 678                chip->cs = spi->chip_select;
 679
 680                if (chip->cs < MAX_CTRL_CS) {
 681                        chip->ssel = (1 << chip->cs) << 8;
 682                        ret = peripheral_request(ssel[spi->master->bus_num]
 683                                        [chip->cs-1], dev_name(&spi->dev));
 684                        if (ret) {
 685                                dev_err(&spi->dev, "peripheral_request() error\n");
 686                                goto error;
 687                        }
 688                } else {
 689                        chip->cs_gpio = chip->cs - MAX_CTRL_CS;
 690                        ret = gpio_request_one(chip->cs_gpio, GPIOF_OUT_INIT_HIGH,
 691                                                dev_name(&spi->dev));
 692                        if (ret) {
 693                                dev_err(&spi->dev, "gpio_request_one() error\n");
 694                                goto error;
 695                        }
 696                }
 697                spi_set_ctldata(spi, chip);
 698        }
 699
 700        /* force a default base state */
 701        chip->control &= ctl_reg;
 702
 703        if (spi->mode & SPI_CPOL)
 704                chip->control |= SPI_CTL_CPOL;
 705        if (spi->mode & SPI_CPHA)
 706                chip->control |= SPI_CTL_CPHA;
 707        if (spi->mode & SPI_LSB_FIRST)
 708                chip->control |= SPI_CTL_LSBF;
 709        chip->control |= SPI_CTL_MSTR;
 710        /* we choose software to controll cs */
 711        chip->control &= ~SPI_CTL_ASSEL;
 712
 713        chip->clock = hz_to_spi_clock(drv_data->sclk, spi->max_speed_hz);
 714
 715        adi_spi_cs_enable(drv_data, chip);
 716        adi_spi_cs_deactive(drv_data, chip);
 717
 718        return 0;
 719error:
 720        if (chip) {
 721                kfree(chip);
 722                spi_set_ctldata(spi, NULL);
 723        }
 724
 725        return ret;
 726}
 727
 728static void adi_spi_cleanup(struct spi_device *spi)
 729{
 730        struct adi_spi_device *chip = spi_get_ctldata(spi);
 731        struct adi_spi_master *drv_data = spi_master_get_devdata(spi->master);
 732
 733        if (!chip)
 734                return;
 735
 736        if (chip->cs < MAX_CTRL_CS) {
 737                peripheral_free(ssel[spi->master->bus_num]
 738                                        [chip->cs-1]);
 739                adi_spi_cs_disable(drv_data, chip);
 740        } else {
 741                gpio_free(chip->cs_gpio);
 742        }
 743
 744        kfree(chip);
 745        spi_set_ctldata(spi, NULL);
 746}
 747
 748static irqreturn_t adi_spi_tx_dma_isr(int irq, void *dev_id)
 749{
 750        struct adi_spi_master *drv_data = dev_id;
 751        u32 dma_stat = get_dma_curr_irqstat(drv_data->tx_dma);
 752        u32 tx_ctl;
 753
 754        clear_dma_irqstat(drv_data->tx_dma);
 755        if (dma_stat & DMA_DONE) {
 756                drv_data->tx_num++;
 757        } else {
 758                dev_err(&drv_data->master->dev,
 759                                "spi tx dma error: %d\n", dma_stat);
 760                if (drv_data->tx)
 761                        drv_data->state = ERROR_STATE;
 762        }
 763        tx_ctl = ioread32(&drv_data->regs->tx_control);
 764        tx_ctl &= ~SPI_TXCTL_TDR_NF;
 765        iowrite32(tx_ctl, &drv_data->regs->tx_control);
 766        return IRQ_HANDLED;
 767}
 768
 769static irqreturn_t adi_spi_rx_dma_isr(int irq, void *dev_id)
 770{
 771        struct adi_spi_master *drv_data = dev_id;
 772        struct spi_message *msg = drv_data->cur_msg;
 773        u32 dma_stat = get_dma_curr_irqstat(drv_data->rx_dma);
 774
 775        clear_dma_irqstat(drv_data->rx_dma);
 776        if (dma_stat & DMA_DONE) {
 777                drv_data->rx_num++;
 778                /* we may fail on tx dma */
 779                if (drv_data->state != ERROR_STATE)
 780                        msg->actual_length += drv_data->transfer_len;
 781        } else {
 782                drv_data->state = ERROR_STATE;
 783                dev_err(&drv_data->master->dev,
 784                                "spi rx dma error: %d\n", dma_stat);
 785        }
 786        iowrite32(0, &drv_data->regs->tx_control);
 787        iowrite32(0, &drv_data->regs->rx_control);
 788        if (drv_data->rx_num != drv_data->tx_num)
 789                dev_dbg(&drv_data->master->dev,
 790                                "dma interrupt missing: tx=%d,rx=%d\n",
 791                                drv_data->tx_num, drv_data->rx_num);
 792        tasklet_schedule(&drv_data->pump_transfers);
 793        return IRQ_HANDLED;
 794}
 795
 796static int adi_spi_probe(struct platform_device *pdev)
 797{
 798        struct device *dev = &pdev->dev;
 799        struct adi_spi3_master *info = dev_get_platdata(dev);
 800        struct spi_master *master;
 801        struct adi_spi_master *drv_data;
 802        struct resource *mem, *res;
 803        unsigned int tx_dma, rx_dma;
 804        struct clk *sclk;
 805        int ret;
 806
 807        if (!info) {
 808                dev_err(dev, "platform data missing!\n");
 809                return -ENODEV;
 810        }
 811
 812        sclk = devm_clk_get(dev, "spi");
 813        if (IS_ERR(sclk)) {
 814                dev_err(dev, "can not get spi clock\n");
 815                return PTR_ERR(sclk);
 816        }
 817
 818        res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
 819        if (!res) {
 820                dev_err(dev, "can not get tx dma resource\n");
 821                return -ENXIO;
 822        }
 823        tx_dma = res->start;
 824
 825        res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
 826        if (!res) {
 827                dev_err(dev, "can not get rx dma resource\n");
 828                return -ENXIO;
 829        }
 830        rx_dma = res->start;
 831
 832        /* allocate master with space for drv_data */
 833        master = spi_alloc_master(dev, sizeof(*drv_data));
 834        if (!master) {
 835                dev_err(dev, "can not alloc spi_master\n");
 836                return -ENOMEM;
 837        }
 838        platform_set_drvdata(pdev, master);
 839
 840        /* the mode bits supported by this driver */
 841        master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
 842
 843        master->bus_num = pdev->id;
 844        master->num_chipselect = info->num_chipselect;
 845        master->cleanup = adi_spi_cleanup;
 846        master->setup = adi_spi_setup;
 847        master->transfer_one_message = adi_spi_transfer_one_message;
 848        master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
 849                                     SPI_BPW_MASK(8);
 850
 851        drv_data = spi_master_get_devdata(master);
 852        drv_data->master = master;
 853        drv_data->tx_dma = tx_dma;
 854        drv_data->rx_dma = rx_dma;
 855        drv_data->pin_req = info->pin_req;
 856        drv_data->sclk = clk_get_rate(sclk);
 857
 858        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 859        drv_data->regs = devm_ioremap_resource(dev, mem);
 860        if (IS_ERR(drv_data->regs)) {
 861                ret = PTR_ERR(drv_data->regs);
 862                goto err_put_master;
 863        }
 864
 865        /* request tx and rx dma */
 866        ret = request_dma(tx_dma, "SPI_TX_DMA");
 867        if (ret) {
 868                dev_err(dev, "can not request SPI TX DMA channel\n");
 869                goto err_put_master;
 870        }
 871        set_dma_callback(tx_dma, adi_spi_tx_dma_isr, drv_data);
 872
 873        ret = request_dma(rx_dma, "SPI_RX_DMA");
 874        if (ret) {
 875                dev_err(dev, "can not request SPI RX DMA channel\n");
 876                goto err_free_tx_dma;
 877        }
 878        set_dma_callback(drv_data->rx_dma, adi_spi_rx_dma_isr, drv_data);
 879
 880        /* request CLK, MOSI and MISO */
 881        ret = peripheral_request_list(drv_data->pin_req, "adi-spi3");
 882        if (ret < 0) {
 883                dev_err(dev, "can not request spi pins\n");
 884                goto err_free_rx_dma;
 885        }
 886
 887        iowrite32(SPI_CTL_MSTR | SPI_CTL_CPHA, &drv_data->regs->control);
 888        iowrite32(0x0000FE00, &drv_data->regs->ssel);
 889        iowrite32(0x0, &drv_data->regs->delay);
 890
 891        tasklet_init(&drv_data->pump_transfers,
 892                        adi_spi_pump_transfers, (unsigned long)drv_data);
 893        /* register with the SPI framework */
 894        ret = devm_spi_register_master(dev, master);
 895        if (ret) {
 896                dev_err(dev, "can not  register spi master\n");
 897                goto err_free_peripheral;
 898        }
 899
 900        return ret;
 901
 902err_free_peripheral:
 903        peripheral_free_list(drv_data->pin_req);
 904err_free_rx_dma:
 905        free_dma(rx_dma);
 906err_free_tx_dma:
 907        free_dma(tx_dma);
 908err_put_master:
 909        spi_master_put(master);
 910
 911        return ret;
 912}
 913
 914static int adi_spi_remove(struct platform_device *pdev)
 915{
 916        struct spi_master *master = platform_get_drvdata(pdev);
 917        struct adi_spi_master *drv_data = spi_master_get_devdata(master);
 918
 919        adi_spi_disable(drv_data);
 920        peripheral_free_list(drv_data->pin_req);
 921        free_dma(drv_data->rx_dma);
 922        free_dma(drv_data->tx_dma);
 923        return 0;
 924}
 925
 926#ifdef CONFIG_PM
 927static int adi_spi_suspend(struct device *dev)
 928{
 929        struct spi_master *master = dev_get_drvdata(dev);
 930        struct adi_spi_master *drv_data = spi_master_get_devdata(master);
 931
 932        spi_master_suspend(master);
 933
 934        drv_data->control = ioread32(&drv_data->regs->control);
 935        drv_data->ssel = ioread32(&drv_data->regs->ssel);
 936
 937        iowrite32(SPI_CTL_MSTR | SPI_CTL_CPHA, &drv_data->regs->control);
 938        iowrite32(0x0000FE00, &drv_data->regs->ssel);
 939        dma_disable_irq(drv_data->rx_dma);
 940        dma_disable_irq(drv_data->tx_dma);
 941
 942        return 0;
 943}
 944
 945static int adi_spi_resume(struct device *dev)
 946{
 947        struct spi_master *master = dev_get_drvdata(dev);
 948        struct adi_spi_master *drv_data = spi_master_get_devdata(master);
 949        int ret = 0;
 950
 951        /* bootrom may modify spi and dma status when resume in spi boot mode */
 952        disable_dma(drv_data->rx_dma);
 953
 954        dma_enable_irq(drv_data->rx_dma);
 955        dma_enable_irq(drv_data->tx_dma);
 956        iowrite32(drv_data->control, &drv_data->regs->control);
 957        iowrite32(drv_data->ssel, &drv_data->regs->ssel);
 958
 959        ret = spi_master_resume(master);
 960        if (ret) {
 961                free_dma(drv_data->rx_dma);
 962                free_dma(drv_data->tx_dma);
 963        }
 964
 965        return ret;
 966}
 967#endif
 968static const struct dev_pm_ops adi_spi_pm_ops = {
 969        SET_SYSTEM_SLEEP_PM_OPS(adi_spi_suspend, adi_spi_resume)
 970};
 971
 972MODULE_ALIAS("platform:adi-spi3");
 973static struct platform_driver adi_spi_driver = {
 974        .driver = {
 975                .name   = "adi-spi3",
 976                .owner  = THIS_MODULE,
 977                .pm     = &adi_spi_pm_ops,
 978        },
 979        .remove         = adi_spi_remove,
 980};
 981
 982module_platform_driver_probe(adi_spi_driver, adi_spi_probe);
 983
 984MODULE_DESCRIPTION("Analog Devices SPI3 controller driver");
 985MODULE_AUTHOR("Scott Jiang <Scott.Jiang.Linux@gmail.com>");
 986MODULE_LICENSE("GPL v2");
 987