drivers/spi/spi-topcliff-pch.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * SPI bus driver for the Topcliff PCH used by Intel SoCs
   4  *
   5  * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
   6  */
   7
   8 #include <linux/delay.h>
   9 #include <linux/pci.h>
  10 #include <linux/wait.h>
  11 #include <linux/spi/spi.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/sched.h>
  14 #include <linux/spi/spidev.h>
  15 #include <linux/module.h>
  16 #include <linux/device.h>
  17 #include <linux/platform_device.h>
  18
  19 #include <linux/dmaengine.h>
  20 #include <linux/pch_dma.h>
  21
  22 /* Register offsets */
  23 #define PCH_SPCR                0x00    /* SPI control register */
  24 #define PCH_SPBRR               0x04    /* SPI baud rate register */
  25 #define PCH_SPSR                0x08    /* SPI status register */
  26 #define PCH_SPDWR               0x0C    /* SPI write data register */
  27 #define PCH_SPDRR               0x10    /* SPI read data register */
  28 #define PCH_SSNXCR              0x18    /* SSN Expand Control Register */
  29 #define PCH_SRST                0x1C    /* SPI reset register */
  30 #define PCH_ADDRESS_SIZE        0x20
  31
  32 #define PCH_SPSR_TFD            0x000007C0
  33 #define PCH_SPSR_RFD            0x0000F800
  34
  35 #define PCH_READABLE(x)         (((x) & PCH_SPSR_RFD)>>11)
  36 #define PCH_WRITABLE(x)         (((x) & PCH_SPSR_TFD)>>6)
  37
  38 #define PCH_RX_THOLD            7
  39 #define PCH_RX_THOLD_MAX        15
  40
  41 #define PCH_TX_THOLD            2
  42
  43 #define PCH_MAX_BAUDRATE        5000000
  44 #define PCH_MAX_FIFO_DEPTH      16
  45
  46 #define STATUS_RUNNING          1
  47 #define STATUS_EXITING          2
  48 #define PCH_SLEEP_TIME          10
  49
  50 #define SSN_LOW                 0x02U
  51 #define SSN_HIGH                0x03U
  52 #define SSN_NO_CONTROL          0x00U
  53 #define PCH_MAX_CS              0xFF
  54 #define PCI_DEVICE_ID_GE_SPI    0x8816
  55
  56 #define SPCR_SPE_BIT            (1 << 0)
  57 #define SPCR_MSTR_BIT           (1 << 1)
  58 #define SPCR_LSBF_BIT           (1 << 4)
  59 #define SPCR_CPHA_BIT           (1 << 5)
  60 #define SPCR_CPOL_BIT           (1 << 6)
  61 #define SPCR_TFIE_BIT           (1 << 8)
  62 #define SPCR_RFIE_BIT           (1 << 9)
  63 #define SPCR_FIE_BIT            (1 << 10)
  64 #define SPCR_ORIE_BIT           (1 << 11)
  65 #define SPCR_MDFIE_BIT          (1 << 12)
  66 #define SPCR_FICLR_BIT          (1 << 24)
  67 #define SPSR_TFI_BIT            (1 << 0)
  68 #define SPSR_RFI_BIT            (1 << 1)
  69 #define SPSR_FI_BIT             (1 << 2)
  70 #define SPSR_ORF_BIT            (1 << 3)
  71 #define SPBRR_SIZE_BIT          (1 << 10)
  72
  73 #define PCH_ALL                 (SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|\
  74                                 SPCR_ORIE_BIT|SPCR_MDFIE_BIT)
  75
  76 #define SPCR_RFIC_FIELD         20
  77 #define SPCR_TFIC_FIELD         16
  78
  79 #define MASK_SPBRR_SPBR_BITS    ((1 << 10) - 1)
  80 #define MASK_RFIC_SPCR_BITS     (0xf << SPCR_RFIC_FIELD)
  81 #define MASK_TFIC_SPCR_BITS     (0xf << SPCR_TFIC_FIELD)
  82
  83 #define PCH_CLOCK_HZ            50000000
  84 #define PCH_MAX_SPBR            1023
  85
  86 /* Definition for ML7213/ML7223/ML7831 by LAPIS Semiconductor */
  87 #define PCI_DEVICE_ID_ML7213_SPI        0x802c
  88 #define PCI_DEVICE_ID_ML7223_SPI        0x800F
  89 #define PCI_DEVICE_ID_ML7831_SPI        0x8816
  90
  91 /*
  92  * Set the number of SPI instance max
  93  * Intel EG20T PCH :            1ch
  94  * LAPIS Semiconductor ML7213 IOH :     2ch
  95  * LAPIS Semiconductor ML7223 IOH :     1ch
  96  * LAPIS Semiconductor ML7831 IOH :     1ch
  97 */
  98 #define PCH_SPI_MAX_DEV                 2
  99
 100 #define PCH_BUF_SIZE            4096
 101 #define PCH_DMA_TRANS_SIZE      12
 102
 103 static int use_dma = 1;
 104
 105 struct pch_spi_dma_ctrl {
 106         struct pci_dev          *dma_dev;
 107         struct dma_async_tx_descriptor  *desc_tx;
 108         struct dma_async_tx_descriptor  *desc_rx;
 109         struct pch_dma_slave            param_tx;
 110         struct pch_dma_slave            param_rx;
 111         struct dma_chan         *chan_tx;
 112         struct dma_chan         *chan_rx;
 113         struct scatterlist              *sg_tx_p;
 114         struct scatterlist              *sg_rx_p;
 115         struct scatterlist              sg_tx;
 116         struct scatterlist              sg_rx;
 117         int                             nent;
 118         void                            *tx_buf_virt;
 119         void                            *rx_buf_virt;
 120         dma_addr_t                      tx_buf_dma;
 121         dma_addr_t                      rx_buf_dma;
 122 };
 123 /**
 124  * struct pch_spi_data - Holds the SPI channel specific details
 125  * @io_remap_addr:              The remapped PCI base address
 126  * @io_base_addr:               Base address
 127  * @master:                     Pointer to the SPI master structure
 128  * @work:                       Reference to work queue handler
 129  * @wait:                       Wait queue for waking up upon receiving an
 130  *                              interrupt.
 131  * @transfer_complete:          Status of SPI Transfer
 132  * @bcurrent_msg_processing:    Status flag for message processing
 133  * @lock:                       Lock for protecting this structure
 134  * @queue:                      SPI Message queue
 135  * @status:                     Status of the SPI driver
 136  * @bpw_len:                    Length of data to be transferred in bits per
 137  *                              word
 138  * @transfer_active:            Flag showing active transfer
 139  * @tx_index:                   Transmit data count; for bookkeeping during
 140  *                              transfer
 141  * @rx_index:                   Receive data count; for bookkeeping during
 142  *                              transfer
 143  * @pkt_tx_buff:                Buffer for data to be transmitted
 144  * @pkt_rx_buff:                Buffer for received data
 145  * @n_curnt_chip:               The chip number that this SPI driver currently
 146  *                              operates on
 147  * @current_chip:               Reference to the current chip that this SPI
 148  *                              driver currently operates on
 149  * @current_msg:                The current message that this SPI driver is
 150  *                              handling
 151  * @cur_trans:                  The current transfer that this SPI driver is
 152  *                              handling
 153  * @board_dat:                  Reference to the SPI device data structure
 154  * @plat_dev:                   platform_device structure
 155  * @ch:                         SPI channel number
 156  * @dma:                        Local DMA information
 157  * @use_dma:                    True if DMA is to be used
 158  * @irq_reg_sts:                Status of IRQ registration
 159  * @save_total_len:             Save length while data is being transferred
 160  */
 161 struct pch_spi_data {
 162         void __iomem *io_remap_addr;
 163         unsigned long io_base_addr;
 164         struct spi_master *master;
 165         struct work_struct work;
 166         wait_queue_head_t wait;
 167         u8 transfer_complete;
 168         u8 bcurrent_msg_processing;
 169         spinlock_t lock;
 170         struct list_head queue;
 171         u8 status;
 172         u32 bpw_len;
 173         u8 transfer_active;
 174         u32 tx_index;
 175         u32 rx_index;
 176         u16 *pkt_tx_buff;
 177         u16 *pkt_rx_buff;
 178         u8 n_curnt_chip;
 179         struct spi_device *current_chip;
 180         struct spi_message *current_msg;
 181         struct spi_transfer *cur_trans;
 182         struct pch_spi_board_data *board_dat;
 183         struct platform_device  *plat_dev;
 184         int ch;
 185         struct pch_spi_dma_ctrl dma;
 186         int use_dma;
 187         u8 irq_reg_sts;
 188         int save_total_len;
 189 };
 190
 191 /**
 192  * struct pch_spi_board_data - Holds the SPI device specific details
 193  * @pdev:               Pointer to the PCI device
 194  * @suspend_sts:        Status of suspend
 195  * @num:                The number of SPI device instance
 196  */
 197 struct pch_spi_board_data {
 198         struct pci_dev *pdev;
 199         u8 suspend_sts;
 200         int num;
 201 };
 202
 203 struct pch_pd_dev_save {
 204         int num;
 205         struct platform_device *pd_save[PCH_SPI_MAX_DEV];
 206         struct pch_spi_board_data *board_dat;
 207 };
 208
 209 static const struct pci_device_id pch_spi_pcidev_id[] = {
 210         { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_GE_SPI),    1, },
 211         { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_SPI), 2, },
 212         { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_SPI), 1, },
 213         { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_SPI), 1, },
 214         { }
 215 };
 216
 217 /**
 218  * pch_spi_writereg() - Performs  register writes
 219  * @master:     Pointer to struct spi_master.
 220  * @idx:        Register offset.
 221  * @val:        Value to be written to register.
 222  */
 223 static inline void pch_spi_writereg(struct spi_master *master, int idx, u32 val)
 224 {
 225         struct pch_spi_data *data = spi_master_get_devdata(master);
 226         iowrite32(val, (data->io_remap_addr + idx));
 227 }
 228
 229 /**
 230  * pch_spi_readreg() - Performs register reads
 231  * @master:     Pointer to struct spi_master.
 232  * @idx:        Register offset.
 233  */
 234 static inline u32 pch_spi_readreg(struct spi_master *master, int idx)
 235 {
 236         struct pch_spi_data *data = spi_master_get_devdata(master);
 237         return ioread32(data->io_remap_addr + idx);
 238 }
 239
 240 static inline void pch_spi_setclr_reg(struct spi_master *master, int idx,
 241                                       u32 set, u32 clr)
 242 {
 243         u32 tmp = pch_spi_readreg(master, idx);
 244         tmp = (tmp & ~clr) | set;
 245         pch_spi_writereg(master, idx, tmp);
 246 }
 247
 248 static void pch_spi_set_master_mode(struct spi_master *master)
 249 {
 250         pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MSTR_BIT, 0);
 251 }
 252
 253 /**
 254  * pch_spi_clear_fifo() - Clears the Transmit and Receive FIFOs
 255  * @master:     Pointer to struct spi_master.
 256  */
 257 static void pch_spi_clear_fifo(struct spi_master *master)
 258 {
 259         pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FICLR_BIT, 0);
 260         pch_spi_setclr_reg(master, PCH_SPCR, 0, SPCR_FICLR_BIT);
 261 }
 262
 263 static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
 264                                 void __iomem *io_remap_addr)
 265 {
 266         u32 n_read, tx_index, rx_index, bpw_len;
 267         u16 *pkt_rx_buffer, *pkt_tx_buff;
 268         int read_cnt;
 269         u32 reg_spcr_val;
 270         void __iomem *spsr;
 271         void __iomem *spdrr;
 272         void __iomem *spdwr;
 273
 274         spsr = io_remap_addr + PCH_SPSR;
 275         iowrite32(reg_spsr_val, spsr);
 276
 277         if (data->transfer_active) {
 278                 rx_index = data->rx_index;
 279                 tx_index = data->tx_index;
 280                 bpw_len = data->bpw_len;
 281                 pkt_rx_buffer = data->pkt_rx_buff;
 282                 pkt_tx_buff = data->pkt_tx_buff;
 283
 284                 spdrr = io_remap_addr + PCH_SPDRR;
 285                 spdwr = io_remap_addr + PCH_SPDWR;
 286
 287                 n_read = PCH_READABLE(reg_spsr_val);
 288
 289                 for (read_cnt = 0; (read_cnt < n_read); read_cnt++) {
 290                         pkt_rx_buffer[rx_index++] = ioread32(spdrr);
 291                         if (tx_index < bpw_len)
 292                                 iowrite32(pkt_tx_buff[tx_index++], spdwr);
 293                 }
 294
 295                 /* disable RFI if not needed */
 296                 if ((bpw_len - rx_index) <= PCH_MAX_FIFO_DEPTH) {
 297                         reg_spcr_val = ioread32(io_remap_addr + PCH_SPCR);
 298                         reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */
 299
 300                         /* reset rx threshold */
 301                         reg_spcr_val &= ~MASK_RFIC_SPCR_BITS;
 302                         reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
 303
 304                         iowrite32(reg_spcr_val, (io_remap_addr + PCH_SPCR));
 305                 }
 306
 307                 /* update counts */
 308                 data->tx_index = tx_index;
 309                 data->rx_index = rx_index;
 310
 311                 /* if transfer complete interrupt */
 312                 if (reg_spsr_val & SPSR_FI_BIT) {
 313                         if ((tx_index == bpw_len) && (rx_index == tx_index)) {
 314                                 /* disable interrupts */
 315                                 pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
 316                                                    PCH_ALL);
 317
 318                                 /* transfer is completed;
 319                                    inform pch_spi_process_messages */
 320                                 data->transfer_complete = true;
 321                                 data->transfer_active = false;
 322                                 wake_up(&data->wait);
 323                         } else {
 324                                 dev_vdbg(&data->master->dev,
 325                                         "%s : Transfer is not completed",
 326                                         __func__);
 327                         }
 328                 }
 329         }
 330 }
 331
 332 /**
 333  * pch_spi_handler() - Interrupt handler
 334  * @irq:        The interrupt number.
 335  * @dev_id:     Pointer to struct pch_spi_board_data.
 336  */
 337 static irqreturn_t pch_spi_handler(int irq, void *dev_id)
 338 {
 339         u32 reg_spsr_val;
 340         void __iomem *spsr;
 341         void __iomem *io_remap_addr;
 342         irqreturn_t ret = IRQ_NONE;
 343         struct pch_spi_data *data = dev_id;
 344         struct pch_spi_board_data *board_dat = data->board_dat;
 345
 346         if (board_dat->suspend_sts) {
 347                 dev_dbg(&board_dat->pdev->dev,
 348                         "%s returning due to suspend\n", __func__);
 349                 return IRQ_NONE;
 350         }
 351
 352         io_remap_addr = data->io_remap_addr;
 353         spsr = io_remap_addr + PCH_SPSR;
 354
 355         reg_spsr_val = ioread32(spsr);
 356
 357         if (reg_spsr_val & SPSR_ORF_BIT) {
 358                 dev_err(&board_dat->pdev->dev, "%s Over run error\n", __func__);
 359                 if (data->current_msg->complete) {
 360                         data->transfer_complete = true;
 361                         data->current_msg->status = -EIO;
 362                         data->current_msg->complete(data->current_msg->context);
 363                         data->bcurrent_msg_processing = false;
 364                         data->current_msg = NULL;
 365                         data->cur_trans = NULL;
 366                 }
 367         }
 368
 369         if (data->use_dma)
 370                 return IRQ_NONE;
 371
 372         /* Check if the interrupt is for SPI device */
 373         if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
 374                 pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
 375                 ret = IRQ_HANDLED;
 376         }
 377
 378         dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n",
 379                 __func__, ret);
 380
 381         return ret;
 382 }
 383
 384 /**
 385  * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR
 386  * @master:     Pointer to struct spi_master.
 387  * @speed_hz:   Baud rate.
 388  */
 389 static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
 390 {
 391         u32 n_spbr = PCH_CLOCK_HZ / (speed_hz * 2);
 392
 393         /* if baud rate is less than we can support limit it */
 394         if (n_spbr > PCH_MAX_SPBR)
 395                 n_spbr = PCH_MAX_SPBR;
 396
 397         pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, MASK_SPBRR_SPBR_BITS);
 398 }
 399
 400 /**
 401  * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR
 402  * @master:             Pointer to struct spi_master.
 403  * @bits_per_word:      Bits per word for SPI transfer.
 404  */
 405 static void pch_spi_set_bits_per_word(struct spi_master *master,
 406                                       u8 bits_per_word)
 407 {
 408         if (bits_per_word == 8)
 409                 pch_spi_setclr_reg(master, PCH_SPBRR, 0, SPBRR_SIZE_BIT);
 410         else
 411                 pch_spi_setclr_reg(master, PCH_SPBRR, SPBRR_SIZE_BIT, 0);
 412 }
 413
 414 /**
 415  * pch_spi_setup_transfer() - Configures the PCH SPI hardware for transfer
 416  * @spi:        Pointer to struct spi_device.
 417  */
 418 static void pch_spi_setup_transfer(struct spi_device *spi)
 419 {
 420         u32 flags = 0;
 421
 422         dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n",
 423                 __func__, pch_spi_readreg(spi->master, PCH_SPBRR),
 424                 spi->max_speed_hz);
 425         pch_spi_set_baud_rate(spi->master, spi->max_speed_hz);
 426
 427         /* set bits per word */
 428         pch_spi_set_bits_per_word(spi->master, spi->bits_per_word);
 429
 430         if (!(spi->mode & SPI_LSB_FIRST))
 431                 flags |= SPCR_LSBF_BIT;
 432         if (spi->mode & SPI_CPOL)
 433                 flags |= SPCR_CPOL_BIT;
 434         if (spi->mode & SPI_CPHA)
 435                 flags |= SPCR_CPHA_BIT;
 436         pch_spi_setclr_reg(spi->master, PCH_SPCR, flags,
 437                            (SPCR_LSBF_BIT | SPCR_CPOL_BIT | SPCR_CPHA_BIT));
 438
 439         /* Clear the FIFO by toggling  FICLR to 1 and back to 0 */
 440         pch_spi_clear_fifo(spi->master);
 441 }
 442
 443 /**
 444  * pch_spi_reset() - Clears SPI registers
 445  * @master:     Pointer to struct spi_master.
 446  */
 447 static void pch_spi_reset(struct spi_master *master)
 448 {
 449         /* write 1 to reset SPI */
 450         pch_spi_writereg(master, PCH_SRST, 0x1);
 451
 452         /* clear reset */
 453         pch_spi_writereg(master, PCH_SRST, 0x0);
 454 }
 455
 456 static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
 457 {
 458         struct pch_spi_data *data = spi_master_get_devdata(pspi->master);
 459         int retval;
 460         unsigned long flags;
 461
 462         /* We won't process any messages if we have been asked to terminate */
 463         if (data->status == STATUS_EXITING) {
 464                 dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
 465                 retval = -ESHUTDOWN;
 466                 goto err_out;
 467         }
 468
 469         /* If suspended ,return -EINVAL */
 470         if (data->board_dat->suspend_sts) {
 471                 dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
 472                 retval = -EINVAL;
 473                 goto err_out;
 474         }
 475
 476         /* set status of message */
 477         pmsg->actual_length = 0;
 478         dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
 479
 480         pmsg->status = -EINPROGRESS;
 481         spin_lock_irqsave(&data->lock, flags);
 482         /* add message to queue */
 483         list_add_tail(&pmsg->queue, &data->queue);
 484         spin_unlock_irqrestore(&data->lock, flags);
 485
 486         dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
 487
 488         schedule_work(&data->work);
 489         dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__);
 490
 491         retval = 0;
 492
 493 err_out:
 494         dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
 495         return retval;
 496 }
 497
 498 static inline void pch_spi_select_chip(struct pch_spi_data *data,
 499                                        struct spi_device *pspi)
 500 {
 501         if (data->current_chip != NULL) {
 502                 if (spi_get_chipselect(pspi, 0) != data->n_curnt_chip) {
 503                         dev_dbg(&pspi->dev, "%s : different slave\n", __func__);
 504                         data->current_chip = NULL;
 505                 }
 506         }
 507
 508         data->current_chip = pspi;
 509
 510         data->n_curnt_chip = spi_get_chipselect(data->current_chip, 0);
 511
 512         dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__);
 513         pch_spi_setup_transfer(pspi);
 514 }
 515
 516 static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw)
 517 {
 518         int size;
 519         u32 n_writes;
 520         int j;
 521         struct spi_message *pmsg, *tmp;
 522         const u8 *tx_buf;
 523         const u16 *tx_sbuf;
 524
 525         /* set baud rate if needed */
 526         if (data->cur_trans->speed_hz) {
 527                 dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
 528                 pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
 529         }
 530
 531         /* set bits per word if needed */
 532         if (data->cur_trans->bits_per_word &&
 533             (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) {
 534                 dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
 535                 pch_spi_set_bits_per_word(data->master,
 536                                           data->cur_trans->bits_per_word);
 537                 *bpw = data->cur_trans->bits_per_word;
 538         } else {
 539                 *bpw = data->current_msg->spi->bits_per_word;
 540         }
 541
 542         /* reset Tx/Rx index */
 543         data->tx_index = 0;
 544         data->rx_index = 0;
 545
 546         data->bpw_len = data->cur_trans->len / (*bpw / 8);
 547
 548         /* find alloc size */
 549         size = data->cur_trans->len * sizeof(*data->pkt_tx_buff);
 550
 551         /* allocate memory for pkt_tx_buff & pkt_rx_buffer */
 552         data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
 553         if (data->pkt_tx_buff != NULL) {
 554                 data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
 555                 if (!data->pkt_rx_buff) {
 556                         kfree(data->pkt_tx_buff);
 557                         data->pkt_tx_buff = NULL;
 558                 }
 559         }
 560
 561         if (!data->pkt_rx_buff) {
 562                 /* flush queue and set status of all transfers to -ENOMEM */
 563                 list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
 564                         pmsg->status = -ENOMEM;
 565
 566                         if (pmsg->complete)
 567                                 pmsg->complete(pmsg->context);
 568
 569                         /* delete from queue */
 570                         list_del_init(&pmsg->queue);
 571                 }
 572                 return;
 573         }
 574
 575         /* copy Tx Data */
 576         if (data->cur_trans->tx_buf != NULL) {
 577                 if (*bpw == 8) {
 578                         tx_buf = data->cur_trans->tx_buf;
 579                         for (j = 0; j < data->bpw_len; j++)
 580                                 data->pkt_tx_buff[j] = *tx_buf++;
 581                 } else {
 582                         tx_sbuf = data->cur_trans->tx_buf;
 583                         for (j = 0; j < data->bpw_len; j++)
 584                                 data->pkt_tx_buff[j] = *tx_sbuf++;
 585                 }
 586         }
 587
 588         /* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
 589         n_writes = data->bpw_len;
 590         if (n_writes > PCH_MAX_FIFO_DEPTH)
 591                 n_writes = PCH_MAX_FIFO_DEPTH;
 592
 593         dev_dbg(&data->master->dev,
 594                 "\n%s:Pulling down SSN low - writing 0x2 to SSNXCR\n",
 595                 __func__);
 596         pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
 597
 598         for (j = 0; j < n_writes; j++)
 599                 pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]);
 600
 601         /* update tx_index */
 602         data->tx_index = j;
 603
 604         /* reset transfer complete flag */
 605         data->transfer_complete = false;
 606         data->transfer_active = true;
 607 }
 608
 609 static void pch_spi_nomore_transfer(struct pch_spi_data *data)
 610 {
 611         struct spi_message *pmsg, *tmp;
 612         dev_dbg(&data->master->dev, "%s called\n", __func__);
 613         /* Invoke complete callback
 614          * [To the spi core..indicating end of transfer] */
 615         data->current_msg->status = 0;
 616
 617         if (data->current_msg->complete) {
 618                 dev_dbg(&data->master->dev,
 619                         "%s:Invoking callback of SPI core\n", __func__);
 620                 data->current_msg->complete(data->current_msg->context);
 621         }
 622
 623         /* update status in global variable */
 624         data->bcurrent_msg_processing = false;
 625
 626         dev_dbg(&data->master->dev,
 627                 "%s:data->bcurrent_msg_processing = false\n", __func__);
 628
 629         data->current_msg = NULL;
 630         data->cur_trans = NULL;
 631
 632         /* check if we have items in list and not suspending
 633          * return 1 if list empty */
 634         if ((list_empty(&data->queue) == 0) &&
 635             (!data->board_dat->suspend_sts) &&
 636             (data->status != STATUS_EXITING)) {
 637                 /* We have some more work to do (either there is more tranint
 638                  * bpw;sfer requests in the current message or there are
 639                  *more messages)
 640                  */
 641                 dev_dbg(&data->master->dev, "%s:Invoke queue_work\n", __func__);
 642                 schedule_work(&data->work);
 643         } else if (data->board_dat->suspend_sts ||
 644                    data->status == STATUS_EXITING) {
 645                 dev_dbg(&data->master->dev,
 646                         "%s suspend/remove initiated, flushing queue\n",
 647                         __func__);
 648                 list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
 649                         pmsg->status = -EIO;
 650
 651                         if (pmsg->complete)
 652                                 pmsg->complete(pmsg->context);
 653
 654                         /* delete from queue */
 655                         list_del_init(&pmsg->queue);
 656                 }
 657         }
 658 }
 659
 660 static void pch_spi_set_ir(struct pch_spi_data *data)
 661 {
 662         /* enable interrupts, set threshold, enable SPI */
 663         if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
 664                 /* set receive threshold to PCH_RX_THOLD */
 665                 pch_spi_setclr_reg(data->master, PCH_SPCR,
 666                                    PCH_RX_THOLD << SPCR_RFIC_FIELD |
 667                                    SPCR_FIE_BIT | SPCR_RFIE_BIT |
 668                                    SPCR_ORIE_BIT | SPCR_SPE_BIT,
 669                                    MASK_RFIC_SPCR_BITS | PCH_ALL);
 670         else
 671                 /* set receive threshold to maximum */
 672                 pch_spi_setclr_reg(data->master, PCH_SPCR,
 673                                    PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD |
 674                                    SPCR_FIE_BIT | SPCR_ORIE_BIT |
 675                                    SPCR_SPE_BIT,
 676                                    MASK_RFIC_SPCR_BITS | PCH_ALL);
 677
 678         /* Wait until the transfer completes; go to sleep after
 679                                  initiating the transfer. */
 680         dev_dbg(&data->master->dev,
 681                 "%s:waiting for transfer to get over\n", __func__);
 682
 683         wait_event_interruptible(data->wait, data->transfer_complete);
 684
 685         /* clear all interrupts */
 686         pch_spi_writereg(data->master, PCH_SPSR,
 687                          pch_spi_readreg(data->master, PCH_SPSR));
 688         /* Disable interrupts and SPI transfer */
 689         pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL | SPCR_SPE_BIT);
 690         /* clear FIFO */
 691         pch_spi_clear_fifo(data->master);
 692 }
 693
 694 static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
 695 {
 696         int j;
 697         u8 *rx_buf;
 698         u16 *rx_sbuf;
 699
 700         /* copy Rx Data */
 701         if (!data->cur_trans->rx_buf)
 702                 return;
 703
 704         if (bpw == 8) {
 705                 rx_buf = data->cur_trans->rx_buf;
 706                 for (j = 0; j < data->bpw_len; j++)
 707                         *rx_buf++ = data->pkt_rx_buff[j] & 0xFF;
 708         } else {
 709                 rx_sbuf = data->cur_trans->rx_buf;
 710                 for (j = 0; j < data->bpw_len; j++)
 711                         *rx_sbuf++ = data->pkt_rx_buff[j];
 712         }
 713 }
 714
 715 static void pch_spi_copy_rx_data_for_dma(struct pch_spi_data *data, int bpw)
 716 {
 717         int j;
 718         u8 *rx_buf;
 719         u16 *rx_sbuf;
 720         const u8 *rx_dma_buf;
 721         const u16 *rx_dma_sbuf;
 722
 723         /* copy Rx Data */
 724         if (!data->cur_trans->rx_buf)
 725                 return;
 726
 727         if (bpw == 8) {
 728                 rx_buf = data->cur_trans->rx_buf;
 729                 rx_dma_buf = data->dma.rx_buf_virt;
 730                 for (j = 0; j < data->bpw_len; j++)
 731                         *rx_buf++ = *rx_dma_buf++ & 0xFF;
 732                 data->cur_trans->rx_buf = rx_buf;
 733         } else {
 734                 rx_sbuf = data->cur_trans->rx_buf;
 735                 rx_dma_sbuf = data->dma.rx_buf_virt;
 736                 for (j = 0; j < data->bpw_len; j++)
 737                         *rx_sbuf++ = *rx_dma_sbuf++;
 738                 data->cur_trans->rx_buf = rx_sbuf;
 739         }
 740 }
 741
 742 static int pch_spi_start_transfer(struct pch_spi_data *data)
 743 {
 744         struct pch_spi_dma_ctrl *dma;
 745         unsigned long flags;
 746         int rtn;
 747
 748         dma = &data->dma;
 749
 750         spin_lock_irqsave(&data->lock, flags);
 751
 752         /* disable interrupts, SPI set enable */
 753         pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_SPE_BIT, PCH_ALL);
 754
 755         spin_unlock_irqrestore(&data->lock, flags);
 756
 757         /* Wait until the transfer completes; go to sleep after
 758                                  initiating the transfer. */
 759         dev_dbg(&data->master->dev,
 760                 "%s:waiting for transfer to get over\n", __func__);
 761         rtn = wait_event_interruptible_timeout(data->wait,
 762                                                data->transfer_complete,
 763                                                msecs_to_jiffies(2 * HZ));
 764         if (!rtn)
 765                 dev_err(&data->master->dev,
 766                         "%s wait-event timeout\n", __func__);
 767
 768         dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent,
 769                             DMA_FROM_DEVICE);
 770
 771         dma_sync_sg_for_cpu(&data->master->dev, dma->sg_tx_p, dma->nent,
 772                             DMA_FROM_DEVICE);
 773         memset(data->dma.tx_buf_virt, 0, PAGE_SIZE);
 774
 775         async_tx_ack(dma->desc_rx);
 776         async_tx_ack(dma->desc_tx);
 777         kfree(dma->sg_tx_p);
 778         kfree(dma->sg_rx_p);
 779
 780         spin_lock_irqsave(&data->lock, flags);
 781
 782         /* clear fifo threshold, disable interrupts, disable SPI transfer */
 783         pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
 784                            MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS | PCH_ALL |
 785                            SPCR_SPE_BIT);
 786         /* clear all interrupts */
 787         pch_spi_writereg(data->master, PCH_SPSR,
 788                          pch_spi_readreg(data->master, PCH_SPSR));
 789         /* clear FIFO */
 790         pch_spi_clear_fifo(data->master);
 791
 792         spin_unlock_irqrestore(&data->lock, flags);
 793
 794         return rtn;
 795 }
 796
 797 static void pch_dma_rx_complete(void *arg)
 798 {
 799         struct pch_spi_data *data = arg;
 800
 801         /* transfer is completed;inform pch_spi_process_messages_dma */
 802         data->transfer_complete = true;
 803         wake_up_interruptible(&data->wait);
 804 }
 805
 806 static bool pch_spi_filter(struct dma_chan *chan, void *slave)
 807 {
 808         struct pch_dma_slave *param = slave;
 809
 810         if ((chan->chan_id == param->chan_id) &&
 811             (param->dma_dev == chan->device->dev)) {
 812                 chan->private = param;
 813                 return true;
 814         } else {
 815                 return false;
 816         }
 817 }
 818
 819 static void pch_spi_request_dma(struct pch_spi_data *data, int bpw)
 820 {
 821         dma_cap_mask_t mask;
 822         struct dma_chan *chan;
 823         struct pci_dev *dma_dev;
 824         struct pch_dma_slave *param;
 825         struct pch_spi_dma_ctrl *dma;
 826         unsigned int width;
 827
 828         if (bpw == 8)
 829                 width = PCH_DMA_WIDTH_1_BYTE;
 830         else
 831                 width = PCH_DMA_WIDTH_2_BYTES;
 832
 833         dma = &data->dma;
 834         dma_cap_zero(mask);
 835         dma_cap_set(DMA_SLAVE, mask);
 836
 837         /* Get DMA's dev information */
 838         dma_dev = pci_get_slot(data->board_dat->pdev->bus,
 839                         PCI_DEVFN(PCI_SLOT(data->board_dat->pdev->devfn), 0));
 840
 841         /* Set Tx DMA */
 842         param = &dma->param_tx;
 843         param->dma_dev = &dma_dev->dev;
 844         param->chan_id = data->ch * 2; /* Tx = 0, 2 */
 845         param->tx_reg = data->io_base_addr + PCH_SPDWR;
 846         param->width = width;
 847         chan = dma_request_channel(mask, pch_spi_filter, param);
 848         if (!chan) {
 849                 dev_err(&data->master->dev,
 850                         "ERROR: dma_request_channel FAILS(Tx)\n");
 851                 goto out;
 852         }
 853         dma->chan_tx = chan;
 854
 855         /* Set Rx DMA */
 856         param = &dma->param_rx;
 857         param->dma_dev = &dma_dev->dev;
 858         param->chan_id = data->ch * 2 + 1; /* Rx = Tx + 1 */
 859         param->rx_reg = data->io_base_addr + PCH_SPDRR;
 860         param->width = width;
 861         chan = dma_request_channel(mask, pch_spi_filter, param);
 862         if (!chan) {
 863                 dev_err(&data->master->dev,
 864                         "ERROR: dma_request_channel FAILS(Rx)\n");
 865                 dma_release_channel(dma->chan_tx);
 866                 dma->chan_tx = NULL;
 867                 goto out;
 868         }
 869         dma->chan_rx = chan;
 870
 871         dma->dma_dev = dma_dev;
 872         return;
 873 out:
 874         pci_dev_put(dma_dev);
 875         data->use_dma = 0;
 876 }
 877
 878 static void pch_spi_release_dma(struct pch_spi_data *data)
 879 {
 880         struct pch_spi_dma_ctrl *dma;
 881
 882         dma = &data->dma;
 883         if (dma->chan_tx) {
 884                 dma_release_channel(dma->chan_tx);
 885                 dma->chan_tx = NULL;
 886         }
 887         if (dma->chan_rx) {
 888                 dma_release_channel(dma->chan_rx);
 889                 dma->chan_rx = NULL;
 890         }
 891
 892         pci_dev_put(dma->dma_dev);
 893 }
 894
 895 static void pch_spi_handle_dma(struct pch_spi_data *data, int *bpw)
 896 {
 897         const u8 *tx_buf;
 898         const u16 *tx_sbuf;
 899         u8 *tx_dma_buf;
 900         u16 *tx_dma_sbuf;
 901         struct scatterlist *sg;
 902         struct dma_async_tx_descriptor *desc_tx;
 903         struct dma_async_tx_descriptor *desc_rx;
 904         int num;
 905         int i;
 906         int size;
 907         int rem;
 908         int head;
 909         unsigned long flags;
 910         struct pch_spi_dma_ctrl *dma;
 911
 912         dma = &data->dma;
 913
 914         /* set baud rate if needed */
 915         if (data->cur_trans->speed_hz) {
 916                 dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
 917                 spin_lock_irqsave(&data->lock, flags);
 918                 pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
 919                 spin_unlock_irqrestore(&data->lock, flags);
 920         }
 921
 922         /* set bits per word if needed */
 923         if (data->cur_trans->bits_per_word &&
 924             (data->current_msg->spi->bits_per_word !=
 925              data->cur_trans->bits_per_word)) {
 926                 dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
 927                 spin_lock_irqsave(&data->lock, flags);
 928                 pch_spi_set_bits_per_word(data->master,
 929                                           data->cur_trans->bits_per_word);
 930                 spin_unlock_irqrestore(&data->lock, flags);
 931                 *bpw = data->cur_trans->bits_per_word;
 932         } else {
 933                 *bpw = data->current_msg->spi->bits_per_word;
 934         }
 935         data->bpw_len = data->cur_trans->len / (*bpw / 8);
 936
 937         if (data->bpw_len > PCH_BUF_SIZE) {
 938                 data->bpw_len = PCH_BUF_SIZE;
 939                 data->cur_trans->len -= PCH_BUF_SIZE;
 940         }
 941
 942         /* copy Tx Data */
 943         if (data->cur_trans->tx_buf != NULL) {
 944                 if (*bpw == 8) {
 945                         tx_buf = data->cur_trans->tx_buf;
 946                         tx_dma_buf = dma->tx_buf_virt;
 947                         for (i = 0; i < data->bpw_len; i++)
 948                                 *tx_dma_buf++ = *tx_buf++;
 949                 } else {
 950                         tx_sbuf = data->cur_trans->tx_buf;
 951                         tx_dma_sbuf = dma->tx_buf_virt;
 952                         for (i = 0; i < data->bpw_len; i++)
 953                                 *tx_dma_sbuf++ = *tx_sbuf++;
 954                 }
 955         }
 956
 957         /* Calculate Rx parameter for DMA transmitting */
 958         if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
 959                 if (data->bpw_len % PCH_DMA_TRANS_SIZE) {
 960                         num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
 961                         rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
 962                 } else {
 963                         num = data->bpw_len / PCH_DMA_TRANS_SIZE;
 964                         rem = PCH_DMA_TRANS_SIZE;
 965                 }
 966                 size = PCH_DMA_TRANS_SIZE;
 967         } else {
 968                 num = 1;
 969                 size = data->bpw_len;
 970                 rem = data->bpw_len;
 971         }
 972         dev_dbg(&data->master->dev, "%s num=%d size=%d rem=%d\n",
 973                 __func__, num, size, rem);
 974         spin_lock_irqsave(&data->lock, flags);
 975
 976         /* set receive fifo threshold and transmit fifo threshold */
 977         pch_spi_setclr_reg(data->master, PCH_SPCR,
 978                            ((size - 1) << SPCR_RFIC_FIELD) |
 979                            (PCH_TX_THOLD << SPCR_TFIC_FIELD),
 980                            MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS);
 981
 982         spin_unlock_irqrestore(&data->lock, flags);
 983
 984         /* RX */
 985         dma->sg_rx_p = kmalloc_array(num, sizeof(*dma->sg_rx_p), GFP_ATOMIC);
 986         if (!dma->sg_rx_p)
 987                 return;
 988
 989         sg_init_table(dma->sg_rx_p, num); /* Initialize SG table */
 990         /* offset, length setting */
 991         sg = dma->sg_rx_p;
 992         for (i = 0; i < num; i++, sg++) {
 993                 if (i == (num - 2)) {
 994                         sg->offset = size * i;
 995                         sg->offset = sg->offset * (*bpw / 8);
 996                         sg_set_page(sg, virt_to_page(dma->rx_buf_virt), rem,
 997                                     sg->offset);
 998                         sg_dma_len(sg) = rem;
 999                 } else if (i == (num - 1)) {
1000                         sg->offset = size * (i - 1) + rem;
1001                         sg->offset = sg->offset * (*bpw / 8);
1002                         sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
1003                                     sg->offset);
1004                         sg_dma_len(sg) = size;
1005                 } else {
1006                         sg->offset = size * i;
1007                         sg->offset = sg->offset * (*bpw / 8);
1008                         sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
1009                                     sg->offset);
1010                         sg_dma_len(sg) = size;
1011                 }
1012                 sg_dma_address(sg) = dma->rx_buf_dma + sg->offset;
1013         }
1014         sg = dma->sg_rx_p;
1015         desc_rx = dmaengine_prep_slave_sg(dma->chan_rx, sg,
1016                                         num, DMA_DEV_TO_MEM,
1017                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1018         if (!desc_rx) {
1019                 dev_err(&data->master->dev,
1020                         "%s:dmaengine_prep_slave_sg Failed\n", __func__);
1021                 return;
1022         }
1023         dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_FROM_DEVICE);
1024         desc_rx->callback = pch_dma_rx_complete;
1025         desc_rx->callback_param = data;
1026         dma->nent = num;
1027         dma->desc_rx = desc_rx;
1028
1029         /* Calculate Tx parameter for DMA transmitting */
1030         if (data->bpw_len > PCH_MAX_FIFO_DEPTH) {
1031                 head = PCH_MAX_FIFO_DEPTH - PCH_DMA_TRANS_SIZE;
1032                 if (data->bpw_len % PCH_DMA_TRANS_SIZE > 4) {
1033                         num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
1034                         rem = data->bpw_len % PCH_DMA_TRANS_SIZE - head;
1035                 } else {
1036                         num = data->bpw_len / PCH_DMA_TRANS_SIZE;
1037                         rem = data->bpw_len % PCH_DMA_TRANS_SIZE +
1038                               PCH_DMA_TRANS_SIZE - head;
1039                 }
1040                 size = PCH_DMA_TRANS_SIZE;
1041         } else {
1042                 num = 1;
1043                 size = data->bpw_len;
1044                 rem = data->bpw_len;
1045                 head = 0;
1046         }
1047
1048         dma->sg_tx_p = kmalloc_array(num, sizeof(*dma->sg_tx_p), GFP_ATOMIC);
1049         if (!dma->sg_tx_p)
1050                 return;
1051
1052         sg_init_table(dma->sg_tx_p, num); /* Initialize SG table */
1053         /* offset, length setting */
1054         sg = dma->sg_tx_p;
1055         for (i = 0; i < num; i++, sg++) {
1056                 if (i == 0) {
1057                         sg->offset = 0;
1058                         sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size + head,
1059                                     sg->offset);
1060                         sg_dma_len(sg) = size + head;
1061                 } else if (i == (num - 1)) {
1062                         sg->offset = head + size * i;
1063                         sg->offset = sg->offset * (*bpw / 8);
1064                         sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem,
1065                                     sg->offset);
1066                         sg_dma_len(sg) = rem;
1067                 } else {
1068                         sg->offset = head + size * i;
1069                         sg->offset = sg->offset * (*bpw / 8);
1070                         sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size,
1071                                     sg->offset);
1072                         sg_dma_len(sg) = size;
1073                 }
1074                 sg_dma_address(sg) = dma->tx_buf_dma + sg->offset;
1075         }
1076         sg = dma->sg_tx_p;
1077         desc_tx = dmaengine_prep_slave_sg(dma->chan_tx,
1078                                         sg, num, DMA_MEM_TO_DEV,
1079                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1080         if (!desc_tx) {
1081                 dev_err(&data->master->dev,
1082                         "%s:dmaengine_prep_slave_sg Failed\n", __func__);
1083                 return;
1084         }
1085         dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_TO_DEVICE);
1086         desc_tx->callback = NULL;
1087         desc_tx->callback_param = data;
1088         dma->nent = num;
1089         dma->desc_tx = desc_tx;
1090
1091         dev_dbg(&data->master->dev, "%s:Pulling down SSN low - writing 0x2 to SSNXCR\n", __func__);
1092
1093         spin_lock_irqsave(&data->lock, flags);
1094         pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
1095         desc_rx->tx_submit(desc_rx);
1096         desc_tx->tx_submit(desc_tx);
1097         spin_unlock_irqrestore(&data->lock, flags);
1098
1099         /* reset transfer complete flag */
1100         data->transfer_complete = false;
1101 }
1102
1103 static void pch_spi_process_messages(struct work_struct *pwork)
1104 {
1105         struct spi_message *pmsg, *tmp;
1106         struct pch_spi_data *data;
1107         int bpw;
1108
1109         data = container_of(pwork, struct pch_spi_data, work);
1110         dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
1111
1112         spin_lock(&data->lock);
1113         /* check if suspend has been initiated;if yes flush queue */
1114         if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
1115                 dev_dbg(&data->master->dev,
1116                         "%s suspend/remove initiated, flushing queue\n", __func__);
1117                 list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
1118                         pmsg->status = -EIO;
1119
1120                         if (pmsg->complete) {
1121                                 spin_unlock(&data->lock);
1122                                 pmsg->complete(pmsg->context);
1123                                 spin_lock(&data->lock);
1124                         }
1125
1126                         /* delete from queue */
1127                         list_del_init(&pmsg->queue);
1128                 }
1129
1130                 spin_unlock(&data->lock);
1131                 return;
1132         }
1133
1134         data->bcurrent_msg_processing = true;
1135         dev_dbg(&data->master->dev,
1136                 "%s Set data->bcurrent_msg_processing= true\n", __func__);
1137
1138         /* Get the message from the queue and delete it from there. */
1139         data->current_msg = list_entry(data->queue.next, struct spi_message,
1140                                         queue);
1141
1142         list_del_init(&data->current_msg->queue);
1143
1144         data->current_msg->status = 0;
1145
1146         pch_spi_select_chip(data, data->current_msg->spi);
1147
1148         spin_unlock(&data->lock);
1149
1150         if (data->use_dma)
1151                 pch_spi_request_dma(data,
1152                                     data->current_msg->spi->bits_per_word);
1153         pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
1154         do {
1155                 int cnt;
1156                 /* If we are already processing a message get the next
1157                 transfer structure from the message otherwise retrieve
1158                 the 1st transfer request from the message. */
1159                 spin_lock(&data->lock);
1160                 if (data->cur_trans == NULL) {
1161                         data->cur_trans =
1162                                 list_entry(data->current_msg->transfers.next,
1163                                            struct spi_transfer, transfer_list);
1164                         dev_dbg(&data->master->dev,
1165                                 "%s :Getting 1st transfer message\n",
1166                                 __func__);
1167                 } else {
1168                         data->cur_trans =
1169                                 list_entry(data->cur_trans->transfer_list.next,
1170                                            struct spi_transfer, transfer_list);
1171                         dev_dbg(&data->master->dev,
1172                                 "%s :Getting next transfer message\n",
1173                                 __func__);
1174                 }
1175                 spin_unlock(&data->lock);
1176
1177                 if (!data->cur_trans->len)
1178                         goto out;
1179                 cnt = (data->cur_trans->len - 1) / PCH_BUF_SIZE + 1;
1180                 data->save_total_len = data->cur_trans->len;
1181                 if (data->use_dma) {
1182                         int i;
1183                         char *save_rx_buf = data->cur_trans->rx_buf;
1184
1185                         for (i = 0; i < cnt; i++) {
1186                                 pch_spi_handle_dma(data, &bpw);
1187                                 if (!pch_spi_start_transfer(data)) {
1188                                         data->transfer_complete = true;
1189                                         data->current_msg->status = -EIO;
1190                                         data->current_msg->complete
1191                                                    (data->current_msg->context);
1192                                         data->bcurrent_msg_processing = false;
1193                                         data->current_msg = NULL;
1194                                         data->cur_trans = NULL;
1195                                         goto out;
1196                                 }
1197                                 pch_spi_copy_rx_data_for_dma(data, bpw);
1198                         }
1199                         data->cur_trans->rx_buf = save_rx_buf;
1200                 } else {
1201                         pch_spi_set_tx(data, &bpw);
1202                         pch_spi_set_ir(data);
1203                         pch_spi_copy_rx_data(data, bpw);
1204                         kfree(data->pkt_rx_buff);
1205                         data->pkt_rx_buff = NULL;
1206                         kfree(data->pkt_tx_buff);
1207                         data->pkt_tx_buff = NULL;
1208                 }
1209                 /* increment message count */
1210                 data->cur_trans->len = data->save_total_len;
1211                 data->current_msg->actual_length += data->cur_trans->len;
1212
1213                 dev_dbg(&data->master->dev,
1214                         "%s:data->current_msg->actual_length=%d\n",
1215                         __func__, data->current_msg->actual_length);
1216
1217                 spi_transfer_delay_exec(data->cur_trans);
1218
1219                 spin_lock(&data->lock);
1220
1221                 /* No more transfer in this message. */
1222                 if ((data->cur_trans->transfer_list.next) ==
1223                     &(data->current_msg->transfers)) {
1224                         pch_spi_nomore_transfer(data);
1225                 }
1226
1227                 spin_unlock(&data->lock);
1228
1229         } while (data->cur_trans != NULL);
1230
1231 out:
1232         pch_spi_writereg(data->master, PCH_SSNXCR, SSN_HIGH);
1233         if (data->use_dma)
1234                 pch_spi_release_dma(data);
1235 }
1236
1237 static void pch_spi_free_resources(struct pch_spi_board_data *board_dat,
1238                                    struct pch_spi_data *data)
1239 {
1240         dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
1241
1242         flush_work(&data->work);
1243 }
1244
1245 static int pch_spi_get_resources(struct pch_spi_board_data *board_dat,
1246                                  struct pch_spi_data *data)
1247 {
1248         dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
1249
1250         /* reset PCH SPI h/w */
1251         pch_spi_reset(data->master);
1252         dev_dbg(&board_dat->pdev->dev,
1253                 "%s pch_spi_reset invoked successfully\n", __func__);
1254
1255         dev_dbg(&board_dat->pdev->dev, "%s data->irq_reg_sts=true\n", __func__);
1256
1257         return 0;
1258 }
1259
1260 static void pch_free_dma_buf(struct pch_spi_board_data *board_dat,
1261                              struct pch_spi_data *data)
1262 {
1263         struct pch_spi_dma_ctrl *dma;
1264
1265         dma = &data->dma;
1266         if (dma->tx_buf_dma)
1267                 dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
1268                                   dma->tx_buf_virt, dma->tx_buf_dma);
1269         if (dma->rx_buf_dma)
1270                 dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
1271                                   dma->rx_buf_virt, dma->rx_buf_dma);
1272 }
1273
1274 static int pch_alloc_dma_buf(struct pch_spi_board_data *board_dat,
1275                               struct pch_spi_data *data)
1276 {
1277         struct pch_spi_dma_ctrl *dma;
1278         int ret;
1279
1280         dma = &data->dma;
1281         ret = 0;
1282         /* Get Consistent memory for Tx DMA */
1283         dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
1284                                 PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL);
1285         if (!dma->tx_buf_virt)
1286                 ret = -ENOMEM;
1287
1288         /* Get Consistent memory for Rx DMA */
1289         dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
1290                                 PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL);
1291         if (!dma->rx_buf_virt)
1292                 ret = -ENOMEM;
1293
1294         return ret;
1295 }
1296
1297 static int pch_spi_pd_probe(struct platform_device *plat_dev)
1298 {
1299         int ret;
1300         struct spi_master *master;
1301         struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
1302         struct pch_spi_data *data;
1303
1304         dev_dbg(&plat_dev->dev, "%s:debug\n", __func__);
1305
1306         master = spi_alloc_master(&board_dat->pdev->dev,
1307                                   sizeof(struct pch_spi_data));
1308         if (!master) {
1309                 dev_err(&plat_dev->dev, "spi_alloc_master[%d] failed.\n",
1310                         plat_dev->id);
1311                 return -ENOMEM;
1312         }
1313
1314         data = spi_master_get_devdata(master);
1315         data->master = master;
1316
1317         platform_set_drvdata(plat_dev, data);
1318
1319         /* baseaddress + address offset) */
1320         data->io_base_addr = pci_resource_start(board_dat->pdev, 1) +
1321                                          PCH_ADDRESS_SIZE * plat_dev->id;
1322         data->io_remap_addr = pci_iomap(board_dat->pdev, 1, 0);
1323         if (!data->io_remap_addr) {
1324                 dev_err(&plat_dev->dev, "%s pci_iomap failed\n", __func__);
1325                 ret = -ENOMEM;
1326                 goto err_pci_iomap;
1327         }
1328         data->io_remap_addr += PCH_ADDRESS_SIZE * plat_dev->id;
1329
1330         dev_dbg(&plat_dev->dev, "[ch%d] remap_addr=%p\n",
1331                 plat_dev->id, data->io_remap_addr);
1332
1333         /* initialize members of SPI master */
1334         master->num_chipselect = PCH_MAX_CS;
1335         master->transfer = pch_spi_transfer;
1336         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1337         master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
1338         master->max_speed_hz = PCH_MAX_BAUDRATE;
1339         master->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
1340
1341         data->board_dat = board_dat;
1342         data->plat_dev = plat_dev;
1343         data->n_curnt_chip = 255;
1344         data->status = STATUS_RUNNING;
1345         data->ch = plat_dev->id;
1346         data->use_dma = use_dma;
1347
1348         INIT_LIST_HEAD(&data->queue);
1349         spin_lock_init(&data->lock);
1350         INIT_WORK(&data->work, pch_spi_process_messages);
1351         init_waitqueue_head(&data->wait);
1352
1353         ret = pch_spi_get_resources(board_dat, data);
1354         if (ret) {
1355                 dev_err(&plat_dev->dev, "%s fail(retval=%d)\n", __func__, ret);
1356                 goto err_spi_get_resources;
1357         }
1358
1359         ret = request_irq(board_dat->pdev->irq, pch_spi_handler,
1360                           IRQF_SHARED, KBUILD_MODNAME, data);
1361         if (ret) {
1362                 dev_err(&plat_dev->dev,
1363                         "%s request_irq failed\n", __func__);
1364                 goto err_request_irq;
1365         }
1366         data->irq_reg_sts = true;
1367
1368         pch_spi_set_master_mode(master);
1369
1370         if (use_dma) {
1371                 dev_info(&plat_dev->dev, "Use DMA for data transfers\n");
1372                 ret = pch_alloc_dma_buf(board_dat, data);
1373                 if (ret)
1374                         goto err_spi_register_master;
1375         }
1376
1377         ret = spi_register_master(master);
1378         if (ret != 0) {
1379                 dev_err(&plat_dev->dev,
1380                         "%s spi_register_master FAILED\n", __func__);
1381                 goto err_spi_register_master;
1382         }
1383
1384         return 0;
1385
1386 err_spi_register_master:
1387         pch_free_dma_buf(board_dat, data);
1388         free_irq(board_dat->pdev->irq, data);
1389 err_request_irq:
1390         pch_spi_free_resources(board_dat, data);
1391 err_spi_get_resources:
1392         pci_iounmap(board_dat->pdev, data->io_remap_addr);
1393 err_pci_iomap:
1394         spi_master_put(master);
1395
1396         return ret;
1397 }
1398
1399 static void pch_spi_pd_remove(struct platform_device *plat_dev)
1400 {
1401         struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
1402         struct pch_spi_data *data = platform_get_drvdata(plat_dev);
1403         int count;
1404         unsigned long flags;
1405
1406         dev_dbg(&plat_dev->dev, "%s:[ch%d] irq=%d\n",
1407                 __func__, plat_dev->id, board_dat->pdev->irq);
1408
1409         if (use_dma)
1410                 pch_free_dma_buf(board_dat, data);
1411
1412         /* check for any pending messages; no action is taken if the queue
1413          * is still full; but at least we tried.  Unload anyway */
1414         count = 500;
1415         spin_lock_irqsave(&data->lock, flags);
1416         data->status = STATUS_EXITING;
1417         while ((list_empty(&data->queue) == 0) && --count) {
1418                 dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
1419                         __func__);
1420                 spin_unlock_irqrestore(&data->lock, flags);
1421                 msleep(PCH_SLEEP_TIME);
1422                 spin_lock_irqsave(&data->lock, flags);
1423         }
1424         spin_unlock_irqrestore(&data->lock, flags);
1425
1426         pch_spi_free_resources(board_dat, data);
1427         /* disable interrupts & free IRQ */
1428         if (data->irq_reg_sts) {
1429                 /* disable interrupts */
1430                 pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
1431                 data->irq_reg_sts = false;
1432                 free_irq(board_dat->pdev->irq, data);
1433         }
1434
1435         pci_iounmap(board_dat->pdev, data->io_remap_addr);
1436         spi_unregister_master(data->master);
1437 }
1438 #ifdef CONFIG_PM
1439 static int pch_spi_pd_suspend(struct platform_device *pd_dev,
1440                               pm_message_t state)
1441 {
1442         u8 count;
1443         struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
1444         struct pch_spi_data *data = platform_get_drvdata(pd_dev);
1445
1446         dev_dbg(&pd_dev->dev, "%s ENTRY\n", __func__);
1447
1448         if (!board_dat) {
1449                 dev_err(&pd_dev->dev,
1450                         "%s pci_get_drvdata returned NULL\n", __func__);
1451                 return -EFAULT;
1452         }
1453
1454         /* check if the current message is processed:
1455            Only after thats done the transfer will be suspended */
1456         count = 255;
1457         while ((--count) > 0) {
1458                 if (!(data->bcurrent_msg_processing))
1459                         break;
1460                 msleep(PCH_SLEEP_TIME);
1461         }
1462
1463         /* Free IRQ */
1464         if (data->irq_reg_sts) {
1465                 /* disable all interrupts */
1466                 pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
1467                 pch_spi_reset(data->master);
1468                 free_irq(board_dat->pdev->irq, data);
1469
1470                 data->irq_reg_sts = false;
1471                 dev_dbg(&pd_dev->dev,
1472                         "%s free_irq invoked successfully.\n", __func__);
1473         }
1474
1475         return 0;
1476 }
1477
1478 static int pch_spi_pd_resume(struct platform_device *pd_dev)
1479 {
1480         struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
1481         struct pch_spi_data *data = platform_get_drvdata(pd_dev);
1482         int retval;
1483
1484         if (!board_dat) {
1485                 dev_err(&pd_dev->dev,
1486                         "%s pci_get_drvdata returned NULL\n", __func__);
1487                 return -EFAULT;
1488         }
1489
1490         if (!data->irq_reg_sts) {
1491                 /* register IRQ */
1492                 retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
1493                                      IRQF_SHARED, KBUILD_MODNAME, data);
1494                 if (retval < 0) {
1495                         dev_err(&pd_dev->dev,
1496                                 "%s request_irq failed\n", __func__);
1497                         return retval;
1498                 }
1499
1500                 /* reset PCH SPI h/w */
1501                 pch_spi_reset(data->master);
1502                 pch_spi_set_master_mode(data->master);
1503                 data->irq_reg_sts = true;
1504         }
1505         return 0;
1506 }
1507 #else
1508 #define pch_spi_pd_suspend NULL
1509 #define pch_spi_pd_resume NULL
1510 #endif
1511
1512 static struct platform_driver pch_spi_pd_driver = {
1513         .driver = {
1514                 .name = "pch-spi",
1515         },
1516         .probe = pch_spi_pd_probe,
1517         .remove_new = pch_spi_pd_remove,
1518         .suspend = pch_spi_pd_suspend,
1519         .resume = pch_spi_pd_resume
1520 };
1521
1522 static int pch_spi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1523 {
1524         struct pch_spi_board_data *board_dat;
1525         struct platform_device *pd_dev = NULL;
1526         int retval;
1527         int i;
1528         struct pch_pd_dev_save *pd_dev_save;
1529
1530         pd_dev_save = kzalloc(sizeof(*pd_dev_save), GFP_KERNEL);
1531         if (!pd_dev_save)
1532                 return -ENOMEM;
1533
1534         board_dat = kzalloc(sizeof(*board_dat), GFP_KERNEL);
1535         if (!board_dat) {
1536                 retval = -ENOMEM;
1537                 goto err_no_mem;
1538         }
1539
1540         retval = pci_request_regions(pdev, KBUILD_MODNAME);
1541         if (retval) {
1542                 dev_err(&pdev->dev, "%s request_region failed\n", __func__);
1543                 goto pci_request_regions;
1544         }
1545
1546         board_dat->pdev = pdev;
1547         board_dat->num = id->driver_data;
1548         pd_dev_save->num = id->driver_data;
1549         pd_dev_save->board_dat = board_dat;
1550
1551         retval = pci_enable_device(pdev);
1552         if (retval) {
1553                 dev_err(&pdev->dev, "%s pci_enable_device failed\n", __func__);
1554                 goto pci_enable_device;
1555         }
1556
1557         for (i = 0; i < board_dat->num; i++) {
1558                 pd_dev = platform_device_alloc("pch-spi", i);
1559                 if (!pd_dev) {
1560                         dev_err(&pdev->dev, "platform_device_alloc failed\n");
1561                         retval = -ENOMEM;
1562                         goto err_platform_device;
1563                 }
1564                 pd_dev_save->pd_save[i] = pd_dev;
1565                 pd_dev->dev.parent = &pdev->dev;
1566
1567                 retval = platform_device_add_data(pd_dev, board_dat,
1568                                                   sizeof(*board_dat));
1569                 if (retval) {
1570                         dev_err(&pdev->dev,
1571                                 "platform_device_add_data failed\n");
1572                         platform_device_put(pd_dev);
1573                         goto err_platform_device;
1574                 }
1575
1576                 retval = platform_device_add(pd_dev);
1577                 if (retval) {
1578                         dev_err(&pdev->dev, "platform_device_add failed\n");
1579                         platform_device_put(pd_dev);
1580                         goto err_platform_device;
1581                 }
1582         }
1583
1584         pci_set_drvdata(pdev, pd_dev_save);
1585
1586         return 0;
1587
1588 err_platform_device:
1589         while (--i >= 0)
1590                 platform_device_unregister(pd_dev_save->pd_save[i]);
1591         pci_disable_device(pdev);
1592 pci_enable_device:
1593         pci_release_regions(pdev);
1594 pci_request_regions:
1595         kfree(board_dat);
1596 err_no_mem:
1597         kfree(pd_dev_save);
1598
1599         return retval;
1600 }
1601
1602 static void pch_spi_remove(struct pci_dev *pdev)
1603 {
1604         int i;
1605         struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1606
1607         dev_dbg(&pdev->dev, "%s ENTRY:pdev=%p\n", __func__, pdev);
1608
1609         for (i = 0; i < pd_dev_save->num; i++)
1610                 platform_device_unregister(pd_dev_save->pd_save[i]);
1611
1612         pci_disable_device(pdev);
1613         pci_release_regions(pdev);
1614         kfree(pd_dev_save->board_dat);
1615         kfree(pd_dev_save);
1616 }
1617
1618 static int __maybe_unused pch_spi_suspend(struct device *dev)
1619 {
1620         struct pch_pd_dev_save *pd_dev_save = dev_get_drvdata(dev);
1621
1622         dev_dbg(dev, "%s ENTRY\n", __func__);
1623
1624         pd_dev_save->board_dat->suspend_sts = true;
1625
1626         return 0;
1627 }
1628
1629 static int __maybe_unused pch_spi_resume(struct device *dev)
1630 {
1631         struct pch_pd_dev_save *pd_dev_save = dev_get_drvdata(dev);
1632
1633         dev_dbg(dev, "%s ENTRY\n", __func__);
1634
1635         /* set suspend status to false */
1636         pd_dev_save->board_dat->suspend_sts = false;
1637
1638         return 0;
1639 }
1640
1641 static SIMPLE_DEV_PM_OPS(pch_spi_pm_ops, pch_spi_suspend, pch_spi_resume);
1642
1643 static struct pci_driver pch_spi_pcidev_driver = {
1644         .name = "pch_spi",
1645         .id_table = pch_spi_pcidev_id,
1646         .probe = pch_spi_probe,
1647         .remove = pch_spi_remove,
1648         .driver.pm = &pch_spi_pm_ops,
1649 };
1650
1651 static int __init pch_spi_init(void)
1652 {
1653         int ret;
1654         ret = platform_driver_register(&pch_spi_pd_driver);
1655         if (ret)
1656                 return ret;
1657
1658         ret = pci_register_driver(&pch_spi_pcidev_driver);
1659         if (ret) {
1660                 platform_driver_unregister(&pch_spi_pd_driver);
1661                 return ret;
1662         }
1663
1664         return 0;
1665 }
1666 module_init(pch_spi_init);
1667
1668 static void __exit pch_spi_exit(void)
1669 {
1670         pci_unregister_driver(&pch_spi_pcidev_driver);
1671         platform_driver_unregister(&pch_spi_pd_driver);
1672 }
1673 module_exit(pch_spi_exit);
1674
1675 module_param(use_dma, int, 0644);
1676 MODULE_PARM_DESC(use_dma,
1677                  "to use DMA for data transfers pass 1 else 0; default 1");
1678
1679 MODULE_LICENSE("GPL");
1680 MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semiconductor ML7xxx IOH SPI Driver");
1681 MODULE_DEVICE_TABLE(pci, pch_spi_pcidev_id);
1682