Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / spi / spi-topcliff-pch.c
diff --git a/kernel/drivers/spi/spi-topcliff-pch.c b/kernel/drivers/spi/spi-topcliff-pch.c
new file mode 100644 (file)
index 0000000..93dfcee
--- /dev/null
@@ -0,0 +1,1754 @@
+/*
+ * SPI bus driver for the Topcliff PCH used by Intel SoCs
+ *
+ * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+#include <linux/spi/spi.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/spi/spidev.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+
+#include <linux/dmaengine.h>
+#include <linux/pch_dma.h>
+
+/* Register offsets */
+#define PCH_SPCR               0x00    /* SPI control register */
+#define PCH_SPBRR              0x04    /* SPI baud rate register */
+#define PCH_SPSR               0x08    /* SPI status register */
+#define PCH_SPDWR              0x0C    /* SPI write data register */
+#define PCH_SPDRR              0x10    /* SPI read data register */
+#define PCH_SSNXCR             0x18    /* SSN Expand Control Register */
+#define PCH_SRST               0x1C    /* SPI reset register */
+#define PCH_ADDRESS_SIZE       0x20
+
+#define PCH_SPSR_TFD           0x000007C0
+#define PCH_SPSR_RFD           0x0000F800
+
+#define PCH_READABLE(x)                (((x) & PCH_SPSR_RFD)>>11)
+#define PCH_WRITABLE(x)                (((x) & PCH_SPSR_TFD)>>6)
+
+#define PCH_RX_THOLD           7
+#define PCH_RX_THOLD_MAX       15
+
+#define PCH_TX_THOLD           2
+
+#define PCH_MAX_BAUDRATE       5000000
+#define PCH_MAX_FIFO_DEPTH     16
+
+#define STATUS_RUNNING         1
+#define STATUS_EXITING         2
+#define PCH_SLEEP_TIME         10
+
+#define SSN_LOW                        0x02U
+#define SSN_HIGH               0x03U
+#define SSN_NO_CONTROL         0x00U
+#define PCH_MAX_CS             0xFF
+#define PCI_DEVICE_ID_GE_SPI   0x8816
+
+#define SPCR_SPE_BIT           (1 << 0)
+#define SPCR_MSTR_BIT          (1 << 1)
+#define SPCR_LSBF_BIT          (1 << 4)
+#define SPCR_CPHA_BIT          (1 << 5)
+#define SPCR_CPOL_BIT          (1 << 6)
+#define SPCR_TFIE_BIT          (1 << 8)
+#define SPCR_RFIE_BIT          (1 << 9)
+#define SPCR_FIE_BIT           (1 << 10)
+#define SPCR_ORIE_BIT          (1 << 11)
+#define SPCR_MDFIE_BIT         (1 << 12)
+#define SPCR_FICLR_BIT         (1 << 24)
+#define SPSR_TFI_BIT           (1 << 0)
+#define SPSR_RFI_BIT           (1 << 1)
+#define SPSR_FI_BIT            (1 << 2)
+#define SPSR_ORF_BIT           (1 << 3)
+#define SPBRR_SIZE_BIT         (1 << 10)
+
+#define PCH_ALL                        (SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|\
+                               SPCR_ORIE_BIT|SPCR_MDFIE_BIT)
+
+#define SPCR_RFIC_FIELD                20
+#define SPCR_TFIC_FIELD                16
+
+#define MASK_SPBRR_SPBR_BITS   ((1 << 10) - 1)
+#define MASK_RFIC_SPCR_BITS    (0xf << SPCR_RFIC_FIELD)
+#define MASK_TFIC_SPCR_BITS    (0xf << SPCR_TFIC_FIELD)
+
+#define PCH_CLOCK_HZ           50000000
+#define PCH_MAX_SPBR           1023
+
+/* Definition for ML7213/ML7223/ML7831 by LAPIS Semiconductor */
+#define PCI_VENDOR_ID_ROHM             0x10DB
+#define PCI_DEVICE_ID_ML7213_SPI       0x802c
+#define PCI_DEVICE_ID_ML7223_SPI       0x800F
+#define PCI_DEVICE_ID_ML7831_SPI       0x8816
+
+/*
+ * Set the number of SPI instance max
+ * Intel EG20T PCH :           1ch
+ * LAPIS Semiconductor ML7213 IOH :    2ch
+ * LAPIS Semiconductor ML7223 IOH :    1ch
+ * LAPIS Semiconductor ML7831 IOH :    1ch
+*/
+#define PCH_SPI_MAX_DEV                        2
+
+#define PCH_BUF_SIZE           4096
+#define PCH_DMA_TRANS_SIZE     12
+
+static int use_dma = 1;
+
+struct pch_spi_dma_ctrl {
+       struct dma_async_tx_descriptor  *desc_tx;
+       struct dma_async_tx_descriptor  *desc_rx;
+       struct pch_dma_slave            param_tx;
+       struct pch_dma_slave            param_rx;
+       struct dma_chan         *chan_tx;
+       struct dma_chan         *chan_rx;
+       struct scatterlist              *sg_tx_p;
+       struct scatterlist              *sg_rx_p;
+       struct scatterlist              sg_tx;
+       struct scatterlist              sg_rx;
+       int                             nent;
+       void                            *tx_buf_virt;
+       void                            *rx_buf_virt;
+       dma_addr_t                      tx_buf_dma;
+       dma_addr_t                      rx_buf_dma;
+};
+/**
+ * struct pch_spi_data - Holds the SPI channel specific details
+ * @io_remap_addr:             The remapped PCI base address
+ * @master:                    Pointer to the SPI master structure
+ * @work:                      Reference to work queue handler
+ * @wk:                                Workqueue for carrying out execution of the
+ *                             requests
+ * @wait:                      Wait queue for waking up upon receiving an
+ *                             interrupt.
+ * @transfer_complete:         Status of SPI Transfer
+ * @bcurrent_msg_processing:   Status flag for message processing
+ * @lock:                      Lock for protecting this structure
+ * @queue:                     SPI Message queue
+ * @status:                    Status of the SPI driver
+ * @bpw_len:                   Length of data to be transferred in bits per
+ *                             word
+ * @transfer_active:           Flag showing active transfer
+ * @tx_index:                  Transmit data count; for bookkeeping during
+ *                             transfer
+ * @rx_index:                  Receive data count; for bookkeeping during
+ *                             transfer
+ * @tx_buff:                   Buffer for data to be transmitted
+ * @rx_index:                  Buffer for Received data
+ * @n_curnt_chip:              The chip number that this SPI driver currently
+ *                             operates on
+ * @current_chip:              Reference to the current chip that this SPI
+ *                             driver currently operates on
+ * @current_msg:               The current message that this SPI driver is
+ *                             handling
+ * @cur_trans:                 The current transfer that this SPI driver is
+ *                             handling
+ * @board_dat:                 Reference to the SPI device data structure
+ * @plat_dev:                  platform_device structure
+ * @ch:                                SPI channel number
+ * @irq_reg_sts:               Status of IRQ registration
+ */
+struct pch_spi_data {
+       void __iomem *io_remap_addr;
+       unsigned long io_base_addr;
+       struct spi_master *master;
+       struct work_struct work;
+       struct workqueue_struct *wk;
+       wait_queue_head_t wait;
+       u8 transfer_complete;
+       u8 bcurrent_msg_processing;
+       spinlock_t lock;
+       struct list_head queue;
+       u8 status;
+       u32 bpw_len;
+       u8 transfer_active;
+       u32 tx_index;
+       u32 rx_index;
+       u16 *pkt_tx_buff;
+       u16 *pkt_rx_buff;
+       u8 n_curnt_chip;
+       struct spi_device *current_chip;
+       struct spi_message *current_msg;
+       struct spi_transfer *cur_trans;
+       struct pch_spi_board_data *board_dat;
+       struct platform_device  *plat_dev;
+       int ch;
+       struct pch_spi_dma_ctrl dma;
+       int use_dma;
+       u8 irq_reg_sts;
+       int save_total_len;
+};
+
+/**
+ * struct pch_spi_board_data - Holds the SPI device specific details
+ * @pdev:              Pointer to the PCI device
+ * @suspend_sts:       Status of suspend
+ * @num:               The number of SPI device instance
+ */
+struct pch_spi_board_data {
+       struct pci_dev *pdev;
+       u8 suspend_sts;
+       int num;
+};
+
+struct pch_pd_dev_save {
+       int num;
+       struct platform_device *pd_save[PCH_SPI_MAX_DEV];
+       struct pch_spi_board_data *board_dat;
+};
+
+static const struct pci_device_id pch_spi_pcidev_id[] = {
+       { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_GE_SPI),    1, },
+       { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_SPI), 2, },
+       { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_SPI), 1, },
+       { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_SPI), 1, },
+       { }
+};
+
+/**
+ * pch_spi_writereg() - Performs  register writes
+ * @master:    Pointer to struct spi_master.
+ * @idx:       Register offset.
+ * @val:       Value to be written to register.
+ */
+static inline void pch_spi_writereg(struct spi_master *master, int idx, u32 val)
+{
+       struct pch_spi_data *data = spi_master_get_devdata(master);
+       iowrite32(val, (data->io_remap_addr + idx));
+}
+
+/**
+ * pch_spi_readreg() - Performs register reads
+ * @master:    Pointer to struct spi_master.
+ * @idx:       Register offset.
+ */
+static inline u32 pch_spi_readreg(struct spi_master *master, int idx)
+{
+       struct pch_spi_data *data = spi_master_get_devdata(master);
+       return ioread32(data->io_remap_addr + idx);
+}
+
+static inline void pch_spi_setclr_reg(struct spi_master *master, int idx,
+                                     u32 set, u32 clr)
+{
+       u32 tmp = pch_spi_readreg(master, idx);
+       tmp = (tmp & ~clr) | set;
+       pch_spi_writereg(master, idx, tmp);
+}
+
+static void pch_spi_set_master_mode(struct spi_master *master)
+{
+       pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MSTR_BIT, 0);
+}
+
+/**
+ * pch_spi_clear_fifo() - Clears the Transmit and Receive FIFOs
+ * @master:    Pointer to struct spi_master.
+ */
+static void pch_spi_clear_fifo(struct spi_master *master)
+{
+       pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FICLR_BIT, 0);
+       pch_spi_setclr_reg(master, PCH_SPCR, 0, SPCR_FICLR_BIT);
+}
+
+static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
+                               void __iomem *io_remap_addr)
+{
+       u32 n_read, tx_index, rx_index, bpw_len;
+       u16 *pkt_rx_buffer, *pkt_tx_buff;
+       int read_cnt;
+       u32 reg_spcr_val;
+       void __iomem *spsr;
+       void __iomem *spdrr;
+       void __iomem *spdwr;
+
+       spsr = io_remap_addr + PCH_SPSR;
+       iowrite32(reg_spsr_val, spsr);
+
+       if (data->transfer_active) {
+               rx_index = data->rx_index;
+               tx_index = data->tx_index;
+               bpw_len = data->bpw_len;
+               pkt_rx_buffer = data->pkt_rx_buff;
+               pkt_tx_buff = data->pkt_tx_buff;
+
+               spdrr = io_remap_addr + PCH_SPDRR;
+               spdwr = io_remap_addr + PCH_SPDWR;
+
+               n_read = PCH_READABLE(reg_spsr_val);
+
+               for (read_cnt = 0; (read_cnt < n_read); read_cnt++) {
+                       pkt_rx_buffer[rx_index++] = ioread32(spdrr);
+                       if (tx_index < bpw_len)
+                               iowrite32(pkt_tx_buff[tx_index++], spdwr);
+               }
+
+               /* disable RFI if not needed */
+               if ((bpw_len - rx_index) <= PCH_MAX_FIFO_DEPTH) {
+                       reg_spcr_val = ioread32(io_remap_addr + PCH_SPCR);
+                       reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */
+
+                       /* reset rx threshold */
+                       reg_spcr_val &= ~MASK_RFIC_SPCR_BITS;
+                       reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
+
+                       iowrite32(reg_spcr_val, (io_remap_addr + PCH_SPCR));
+               }
+
+               /* update counts */
+               data->tx_index = tx_index;
+               data->rx_index = rx_index;
+
+               /* if transfer complete interrupt */
+               if (reg_spsr_val & SPSR_FI_BIT) {
+                       if ((tx_index == bpw_len) && (rx_index == tx_index)) {
+                               /* disable interrupts */
+                               pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
+                                                  PCH_ALL);
+
+                               /* transfer is completed;
+                                  inform pch_spi_process_messages */
+                               data->transfer_complete = true;
+                               data->transfer_active = false;
+                               wake_up(&data->wait);
+                       } else {
+                               dev_vdbg(&data->master->dev,
+                                       "%s : Transfer is not completed",
+                                       __func__);
+                       }
+               }
+       }
+}
+
+/**
+ * pch_spi_handler() - Interrupt handler
+ * @irq:       The interrupt number.
+ * @dev_id:    Pointer to struct pch_spi_board_data.
+ */
+static irqreturn_t pch_spi_handler(int irq, void *dev_id)
+{
+       u32 reg_spsr_val;
+       void __iomem *spsr;
+       void __iomem *io_remap_addr;
+       irqreturn_t ret = IRQ_NONE;
+       struct pch_spi_data *data = dev_id;
+       struct pch_spi_board_data *board_dat = data->board_dat;
+
+       if (board_dat->suspend_sts) {
+               dev_dbg(&board_dat->pdev->dev,
+                       "%s returning due to suspend\n", __func__);
+               return IRQ_NONE;
+       }
+
+       io_remap_addr = data->io_remap_addr;
+       spsr = io_remap_addr + PCH_SPSR;
+
+       reg_spsr_val = ioread32(spsr);
+
+       if (reg_spsr_val & SPSR_ORF_BIT) {
+               dev_err(&board_dat->pdev->dev, "%s Over run error\n", __func__);
+               if (data->current_msg->complete) {
+                       data->transfer_complete = true;
+                       data->current_msg->status = -EIO;
+                       data->current_msg->complete(data->current_msg->context);
+                       data->bcurrent_msg_processing = false;
+                       data->current_msg = NULL;
+                       data->cur_trans = NULL;
+               }
+       }
+
+       if (data->use_dma)
+               return IRQ_NONE;
+
+       /* Check if the interrupt is for SPI device */
+       if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
+               pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
+               ret = IRQ_HANDLED;
+       }
+
+       dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n",
+               __func__, ret);
+
+       return ret;
+}
+
+/**
+ * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR
+ * @master:    Pointer to struct spi_master.
+ * @speed_hz:  Baud rate.
+ */
+static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
+{
+       u32 n_spbr = PCH_CLOCK_HZ / (speed_hz * 2);
+
+       /* if baud rate is less than we can support limit it */
+       if (n_spbr > PCH_MAX_SPBR)
+               n_spbr = PCH_MAX_SPBR;
+
+       pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, MASK_SPBRR_SPBR_BITS);
+}
+
+/**
+ * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR
+ * @master:            Pointer to struct spi_master.
+ * @bits_per_word:     Bits per word for SPI transfer.
+ */
+static void pch_spi_set_bits_per_word(struct spi_master *master,
+                                     u8 bits_per_word)
+{
+       if (bits_per_word == 8)
+               pch_spi_setclr_reg(master, PCH_SPBRR, 0, SPBRR_SIZE_BIT);
+       else
+               pch_spi_setclr_reg(master, PCH_SPBRR, SPBRR_SIZE_BIT, 0);
+}
+
+/**
+ * pch_spi_setup_transfer() - Configures the PCH SPI hardware for transfer
+ * @spi:       Pointer to struct spi_device.
+ */
+static void pch_spi_setup_transfer(struct spi_device *spi)
+{
+       u32 flags = 0;
+
+       dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n",
+               __func__, pch_spi_readreg(spi->master, PCH_SPBRR),
+               spi->max_speed_hz);
+       pch_spi_set_baud_rate(spi->master, spi->max_speed_hz);
+
+       /* set bits per word */
+       pch_spi_set_bits_per_word(spi->master, spi->bits_per_word);
+
+       if (!(spi->mode & SPI_LSB_FIRST))
+               flags |= SPCR_LSBF_BIT;
+       if (spi->mode & SPI_CPOL)
+               flags |= SPCR_CPOL_BIT;
+       if (spi->mode & SPI_CPHA)
+               flags |= SPCR_CPHA_BIT;
+       pch_spi_setclr_reg(spi->master, PCH_SPCR, flags,
+                          (SPCR_LSBF_BIT | SPCR_CPOL_BIT | SPCR_CPHA_BIT));
+
+       /* Clear the FIFO by toggling  FICLR to 1 and back to 0 */
+       pch_spi_clear_fifo(spi->master);
+}
+
+/**
+ * pch_spi_reset() - Clears SPI registers
+ * @master:    Pointer to struct spi_master.
+ */
+static void pch_spi_reset(struct spi_master *master)
+{
+       /* write 1 to reset SPI */
+       pch_spi_writereg(master, PCH_SRST, 0x1);
+
+       /* clear reset */
+       pch_spi_writereg(master, PCH_SRST, 0x0);
+}
+
+static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
+{
+
+       struct spi_transfer *transfer;
+       struct pch_spi_data *data = spi_master_get_devdata(pspi->master);
+       int retval;
+       unsigned long flags;
+
+       spin_lock_irqsave(&data->lock, flags);
+       /* validate Tx/Rx buffers and Transfer length */
+       list_for_each_entry(transfer, &pmsg->transfers, transfer_list) {
+               if (!transfer->tx_buf && !transfer->rx_buf) {
+                       dev_err(&pspi->dev,
+                               "%s Tx and Rx buffer NULL\n", __func__);
+                       retval = -EINVAL;
+                       goto err_return_spinlock;
+               }
+
+               if (!transfer->len) {
+                       dev_err(&pspi->dev, "%s Transfer length invalid\n",
+                               __func__);
+                       retval = -EINVAL;
+                       goto err_return_spinlock;
+               }
+
+               dev_dbg(&pspi->dev,
+                       "%s Tx/Rx buffer valid. Transfer length valid\n",
+                       __func__);
+       }
+       spin_unlock_irqrestore(&data->lock, flags);
+
+       /* We won't process any messages if we have been asked to terminate */
+       if (data->status == STATUS_EXITING) {
+               dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
+               retval = -ESHUTDOWN;
+               goto err_out;
+       }
+
+       /* If suspended ,return -EINVAL */
+       if (data->board_dat->suspend_sts) {
+               dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
+               retval = -EINVAL;
+               goto err_out;
+       }
+
+       /* set status of message */
+       pmsg->actual_length = 0;
+       dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
+
+       pmsg->status = -EINPROGRESS;
+       spin_lock_irqsave(&data->lock, flags);
+       /* add message to queue */
+       list_add_tail(&pmsg->queue, &data->queue);
+       spin_unlock_irqrestore(&data->lock, flags);
+
+       dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
+
+       /* schedule work queue to run */
+       queue_work(data->wk, &data->work);
+       dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__);
+
+       retval = 0;
+
+err_out:
+       dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
+       return retval;
+err_return_spinlock:
+       dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
+       spin_unlock_irqrestore(&data->lock, flags);
+       return retval;
+}
+
+static inline void pch_spi_select_chip(struct pch_spi_data *data,
+                                      struct spi_device *pspi)
+{
+       if (data->current_chip != NULL) {
+               if (pspi->chip_select != data->n_curnt_chip) {
+                       dev_dbg(&pspi->dev, "%s : different slave\n", __func__);
+                       data->current_chip = NULL;
+               }
+       }
+
+       data->current_chip = pspi;
+
+       data->n_curnt_chip = data->current_chip->chip_select;
+
+       dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__);
+       pch_spi_setup_transfer(pspi);
+}
+
+static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw)
+{
+       int size;
+       u32 n_writes;
+       int j;
+       struct spi_message *pmsg, *tmp;
+       const u8 *tx_buf;
+       const u16 *tx_sbuf;
+
+       /* set baud rate if needed */
+       if (data->cur_trans->speed_hz) {
+               dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
+               pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
+       }
+
+       /* set bits per word if needed */
+       if (data->cur_trans->bits_per_word &&
+           (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) {
+               dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
+               pch_spi_set_bits_per_word(data->master,
+                                         data->cur_trans->bits_per_word);
+               *bpw = data->cur_trans->bits_per_word;
+       } else {
+               *bpw = data->current_msg->spi->bits_per_word;
+       }
+
+       /* reset Tx/Rx index */
+       data->tx_index = 0;
+       data->rx_index = 0;
+
+       data->bpw_len = data->cur_trans->len / (*bpw / 8);
+
+       /* find alloc size */
+       size = data->cur_trans->len * sizeof(*data->pkt_tx_buff);
+
+       /* allocate memory for pkt_tx_buff & pkt_rx_buffer */
+       data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
+       if (data->pkt_tx_buff != NULL) {
+               data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
+               if (!data->pkt_rx_buff)
+                       kfree(data->pkt_tx_buff);
+       }
+
+       if (!data->pkt_rx_buff) {
+               /* flush queue and set status of all transfers to -ENOMEM */
+               dev_err(&data->master->dev, "%s :kzalloc failed\n", __func__);
+               list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
+                       pmsg->status = -ENOMEM;
+
+                       if (pmsg->complete)
+                               pmsg->complete(pmsg->context);
+
+                       /* delete from queue */
+                       list_del_init(&pmsg->queue);
+               }
+               return;
+       }
+
+       /* copy Tx Data */
+       if (data->cur_trans->tx_buf != NULL) {
+               if (*bpw == 8) {
+                       tx_buf = data->cur_trans->tx_buf;
+                       for (j = 0; j < data->bpw_len; j++)
+                               data->pkt_tx_buff[j] = *tx_buf++;
+               } else {
+                       tx_sbuf = data->cur_trans->tx_buf;
+                       for (j = 0; j < data->bpw_len; j++)
+                               data->pkt_tx_buff[j] = *tx_sbuf++;
+               }
+       }
+
+       /* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
+       n_writes = data->bpw_len;
+       if (n_writes > PCH_MAX_FIFO_DEPTH)
+               n_writes = PCH_MAX_FIFO_DEPTH;
+
+       dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
+               "0x2 to SSNXCR\n", __func__);
+       pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
+
+       for (j = 0; j < n_writes; j++)
+               pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]);
+
+       /* update tx_index */
+       data->tx_index = j;
+
+       /* reset transfer complete flag */
+       data->transfer_complete = false;
+       data->transfer_active = true;
+}
+
+static void pch_spi_nomore_transfer(struct pch_spi_data *data)
+{
+       struct spi_message *pmsg, *tmp;
+       dev_dbg(&data->master->dev, "%s called\n", __func__);
+       /* Invoke complete callback
+        * [To the spi core..indicating end of transfer] */
+       data->current_msg->status = 0;
+
+       if (data->current_msg->complete) {
+               dev_dbg(&data->master->dev,
+                       "%s:Invoking callback of SPI core\n", __func__);
+               data->current_msg->complete(data->current_msg->context);
+       }
+
+       /* update status in global variable */
+       data->bcurrent_msg_processing = false;
+
+       dev_dbg(&data->master->dev,
+               "%s:data->bcurrent_msg_processing = false\n", __func__);
+
+       data->current_msg = NULL;
+       data->cur_trans = NULL;
+
+       /* check if we have items in list and not suspending
+        * return 1 if list empty */
+       if ((list_empty(&data->queue) == 0) &&
+           (!data->board_dat->suspend_sts) &&
+           (data->status != STATUS_EXITING)) {
+               /* We have some more work to do (either there is more tranint
+                * bpw;sfer requests in the current message or there are
+                *more messages)
+                */
+               dev_dbg(&data->master->dev, "%s:Invoke queue_work\n", __func__);
+               queue_work(data->wk, &data->work);
+       } else if (data->board_dat->suspend_sts ||
+                  data->status == STATUS_EXITING) {
+               dev_dbg(&data->master->dev,
+                       "%s suspend/remove initiated, flushing queue\n",
+                       __func__);
+               list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
+                       pmsg->status = -EIO;
+
+                       if (pmsg->complete)
+                               pmsg->complete(pmsg->context);
+
+                       /* delete from queue */
+                       list_del_init(&pmsg->queue);
+               }
+       }
+}
+
+static void pch_spi_set_ir(struct pch_spi_data *data)
+{
+       /* enable interrupts, set threshold, enable SPI */
+       if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
+               /* set receive threshold to PCH_RX_THOLD */
+               pch_spi_setclr_reg(data->master, PCH_SPCR,
+                                  PCH_RX_THOLD << SPCR_RFIC_FIELD |
+                                  SPCR_FIE_BIT | SPCR_RFIE_BIT |
+                                  SPCR_ORIE_BIT | SPCR_SPE_BIT,
+                                  MASK_RFIC_SPCR_BITS | PCH_ALL);
+       else
+               /* set receive threshold to maximum */
+               pch_spi_setclr_reg(data->master, PCH_SPCR,
+                                  PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD |
+                                  SPCR_FIE_BIT | SPCR_ORIE_BIT |
+                                  SPCR_SPE_BIT,
+                                  MASK_RFIC_SPCR_BITS | PCH_ALL);
+
+       /* Wait until the transfer completes; go to sleep after
+                                initiating the transfer. */
+       dev_dbg(&data->master->dev,
+               "%s:waiting for transfer to get over\n", __func__);
+
+       wait_event_interruptible(data->wait, data->transfer_complete);
+
+       /* clear all interrupts */
+       pch_spi_writereg(data->master, PCH_SPSR,
+                        pch_spi_readreg(data->master, PCH_SPSR));
+       /* Disable interrupts and SPI transfer */
+       pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL | SPCR_SPE_BIT);
+       /* clear FIFO */
+       pch_spi_clear_fifo(data->master);
+}
+
+static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
+{
+       int j;
+       u8 *rx_buf;
+       u16 *rx_sbuf;
+
+       /* copy Rx Data */
+       if (!data->cur_trans->rx_buf)
+               return;
+
+       if (bpw == 8) {
+               rx_buf = data->cur_trans->rx_buf;
+               for (j = 0; j < data->bpw_len; j++)
+                       *rx_buf++ = data->pkt_rx_buff[j] & 0xFF;
+       } else {
+               rx_sbuf = data->cur_trans->rx_buf;
+               for (j = 0; j < data->bpw_len; j++)
+                       *rx_sbuf++ = data->pkt_rx_buff[j];
+       }
+}
+
+static void pch_spi_copy_rx_data_for_dma(struct pch_spi_data *data, int bpw)
+{
+       int j;
+       u8 *rx_buf;
+       u16 *rx_sbuf;
+       const u8 *rx_dma_buf;
+       const u16 *rx_dma_sbuf;
+
+       /* copy Rx Data */
+       if (!data->cur_trans->rx_buf)
+               return;
+
+       if (bpw == 8) {
+               rx_buf = data->cur_trans->rx_buf;
+               rx_dma_buf = data->dma.rx_buf_virt;
+               for (j = 0; j < data->bpw_len; j++)
+                       *rx_buf++ = *rx_dma_buf++ & 0xFF;
+               data->cur_trans->rx_buf = rx_buf;
+       } else {
+               rx_sbuf = data->cur_trans->rx_buf;
+               rx_dma_sbuf = data->dma.rx_buf_virt;
+               for (j = 0; j < data->bpw_len; j++)
+                       *rx_sbuf++ = *rx_dma_sbuf++;
+               data->cur_trans->rx_buf = rx_sbuf;
+       }
+}
+
+static int pch_spi_start_transfer(struct pch_spi_data *data)
+{
+       struct pch_spi_dma_ctrl *dma;
+       unsigned long flags;
+       int rtn;
+
+       dma = &data->dma;
+
+       spin_lock_irqsave(&data->lock, flags);
+
+       /* disable interrupts, SPI set enable */
+       pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_SPE_BIT, PCH_ALL);
+
+       spin_unlock_irqrestore(&data->lock, flags);
+
+       /* Wait until the transfer completes; go to sleep after
+                                initiating the transfer. */
+       dev_dbg(&data->master->dev,
+               "%s:waiting for transfer to get over\n", __func__);
+       rtn = wait_event_interruptible_timeout(data->wait,
+                                              data->transfer_complete,
+                                              msecs_to_jiffies(2 * HZ));
+       if (!rtn)
+               dev_err(&data->master->dev,
+                       "%s wait-event timeout\n", __func__);
+
+       dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent,
+                           DMA_FROM_DEVICE);
+
+       dma_sync_sg_for_cpu(&data->master->dev, dma->sg_tx_p, dma->nent,
+                           DMA_FROM_DEVICE);
+       memset(data->dma.tx_buf_virt, 0, PAGE_SIZE);
+
+       async_tx_ack(dma->desc_rx);
+       async_tx_ack(dma->desc_tx);
+       kfree(dma->sg_tx_p);
+       kfree(dma->sg_rx_p);
+
+       spin_lock_irqsave(&data->lock, flags);
+
+       /* clear fifo threshold, disable interrupts, disable SPI transfer */
+       pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
+                          MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS | PCH_ALL |
+                          SPCR_SPE_BIT);
+       /* clear all interrupts */
+       pch_spi_writereg(data->master, PCH_SPSR,
+                        pch_spi_readreg(data->master, PCH_SPSR));
+       /* clear FIFO */
+       pch_spi_clear_fifo(data->master);
+
+       spin_unlock_irqrestore(&data->lock, flags);
+
+       return rtn;
+}
+
+static void pch_dma_rx_complete(void *arg)
+{
+       struct pch_spi_data *data = arg;
+
+       /* transfer is completed;inform pch_spi_process_messages_dma */
+       data->transfer_complete = true;
+       wake_up_interruptible(&data->wait);
+}
+
+static bool pch_spi_filter(struct dma_chan *chan, void *slave)
+{
+       struct pch_dma_slave *param = slave;
+
+       if ((chan->chan_id == param->chan_id) &&
+           (param->dma_dev == chan->device->dev)) {
+               chan->private = param;
+               return true;
+       } else {
+               return false;
+       }
+}
+
+static void pch_spi_request_dma(struct pch_spi_data *data, int bpw)
+{
+       dma_cap_mask_t mask;
+       struct dma_chan *chan;
+       struct pci_dev *dma_dev;
+       struct pch_dma_slave *param;
+       struct pch_spi_dma_ctrl *dma;
+       unsigned int width;
+
+       if (bpw == 8)
+               width = PCH_DMA_WIDTH_1_BYTE;
+       else
+               width = PCH_DMA_WIDTH_2_BYTES;
+
+       dma = &data->dma;
+       dma_cap_zero(mask);
+       dma_cap_set(DMA_SLAVE, mask);
+
+       /* Get DMA's dev information */
+       dma_dev = pci_get_slot(data->board_dat->pdev->bus,
+                       PCI_DEVFN(PCI_SLOT(data->board_dat->pdev->devfn), 0));
+
+       /* Set Tx DMA */
+       param = &dma->param_tx;
+       param->dma_dev = &dma_dev->dev;
+       param->chan_id = data->ch * 2; /* Tx = 0, 2 */;
+       param->tx_reg = data->io_base_addr + PCH_SPDWR;
+       param->width = width;
+       chan = dma_request_channel(mask, pch_spi_filter, param);
+       if (!chan) {
+               dev_err(&data->master->dev,
+                       "ERROR: dma_request_channel FAILS(Tx)\n");
+               data->use_dma = 0;
+               return;
+       }
+       dma->chan_tx = chan;
+
+       /* Set Rx DMA */
+       param = &dma->param_rx;
+       param->dma_dev = &dma_dev->dev;
+       param->chan_id = data->ch * 2 + 1; /* Rx = Tx + 1 */;
+       param->rx_reg = data->io_base_addr + PCH_SPDRR;
+       param->width = width;
+       chan = dma_request_channel(mask, pch_spi_filter, param);
+       if (!chan) {
+               dev_err(&data->master->dev,
+                       "ERROR: dma_request_channel FAILS(Rx)\n");
+               dma_release_channel(dma->chan_tx);
+               dma->chan_tx = NULL;
+               data->use_dma = 0;
+               return;
+       }
+       dma->chan_rx = chan;
+}
+
+static void pch_spi_release_dma(struct pch_spi_data *data)
+{
+       struct pch_spi_dma_ctrl *dma;
+
+       dma = &data->dma;
+       if (dma->chan_tx) {
+               dma_release_channel(dma->chan_tx);
+               dma->chan_tx = NULL;
+       }
+       if (dma->chan_rx) {
+               dma_release_channel(dma->chan_rx);
+               dma->chan_rx = NULL;
+       }
+       return;
+}
+
+static void pch_spi_handle_dma(struct pch_spi_data *data, int *bpw)
+{
+       const u8 *tx_buf;
+       const u16 *tx_sbuf;
+       u8 *tx_dma_buf;
+       u16 *tx_dma_sbuf;
+       struct scatterlist *sg;
+       struct dma_async_tx_descriptor *desc_tx;
+       struct dma_async_tx_descriptor *desc_rx;
+       int num;
+       int i;
+       int size;
+       int rem;
+       int head;
+       unsigned long flags;
+       struct pch_spi_dma_ctrl *dma;
+
+       dma = &data->dma;
+
+       /* set baud rate if needed */
+       if (data->cur_trans->speed_hz) {
+               dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
+               spin_lock_irqsave(&data->lock, flags);
+               pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
+               spin_unlock_irqrestore(&data->lock, flags);
+       }
+
+       /* set bits per word if needed */
+       if (data->cur_trans->bits_per_word &&
+           (data->current_msg->spi->bits_per_word !=
+            data->cur_trans->bits_per_word)) {
+               dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
+               spin_lock_irqsave(&data->lock, flags);
+               pch_spi_set_bits_per_word(data->master,
+                                         data->cur_trans->bits_per_word);
+               spin_unlock_irqrestore(&data->lock, flags);
+               *bpw = data->cur_trans->bits_per_word;
+       } else {
+               *bpw = data->current_msg->spi->bits_per_word;
+       }
+       data->bpw_len = data->cur_trans->len / (*bpw / 8);
+
+       if (data->bpw_len > PCH_BUF_SIZE) {
+               data->bpw_len = PCH_BUF_SIZE;
+               data->cur_trans->len -= PCH_BUF_SIZE;
+       }
+
+       /* copy Tx Data */
+       if (data->cur_trans->tx_buf != NULL) {
+               if (*bpw == 8) {
+                       tx_buf = data->cur_trans->tx_buf;
+                       tx_dma_buf = dma->tx_buf_virt;
+                       for (i = 0; i < data->bpw_len; i++)
+                               *tx_dma_buf++ = *tx_buf++;
+               } else {
+                       tx_sbuf = data->cur_trans->tx_buf;
+                       tx_dma_sbuf = dma->tx_buf_virt;
+                       for (i = 0; i < data->bpw_len; i++)
+                               *tx_dma_sbuf++ = *tx_sbuf++;
+               }
+       }
+
+       /* Calculate Rx parameter for DMA transmitting */
+       if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
+               if (data->bpw_len % PCH_DMA_TRANS_SIZE) {
+                       num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
+                       rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
+               } else {
+                       num = data->bpw_len / PCH_DMA_TRANS_SIZE;
+                       rem = PCH_DMA_TRANS_SIZE;
+               }
+               size = PCH_DMA_TRANS_SIZE;
+       } else {
+               num = 1;
+               size = data->bpw_len;
+               rem = data->bpw_len;
+       }
+       dev_dbg(&data->master->dev, "%s num=%d size=%d rem=%d\n",
+               __func__, num, size, rem);
+       spin_lock_irqsave(&data->lock, flags);
+
+       /* set receive fifo threshold and transmit fifo threshold */
+       pch_spi_setclr_reg(data->master, PCH_SPCR,
+                          ((size - 1) << SPCR_RFIC_FIELD) |
+                          (PCH_TX_THOLD << SPCR_TFIC_FIELD),
+                          MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS);
+
+       spin_unlock_irqrestore(&data->lock, flags);
+
+       /* RX */
+       dma->sg_rx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
+       sg_init_table(dma->sg_rx_p, num); /* Initialize SG table */
+       /* offset, length setting */
+       sg = dma->sg_rx_p;
+       for (i = 0; i < num; i++, sg++) {
+               if (i == (num - 2)) {
+                       sg->offset = size * i;
+                       sg->offset = sg->offset * (*bpw / 8);
+                       sg_set_page(sg, virt_to_page(dma->rx_buf_virt), rem,
+                                   sg->offset);
+                       sg_dma_len(sg) = rem;
+               } else if (i == (num - 1)) {
+                       sg->offset = size * (i - 1) + rem;
+                       sg->offset = sg->offset * (*bpw / 8);
+                       sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
+                                   sg->offset);
+                       sg_dma_len(sg) = size;
+               } else {
+                       sg->offset = size * i;
+                       sg->offset = sg->offset * (*bpw / 8);
+                       sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
+                                   sg->offset);
+                       sg_dma_len(sg) = size;
+               }
+               sg_dma_address(sg) = dma->rx_buf_dma + sg->offset;
+       }
+       sg = dma->sg_rx_p;
+       desc_rx = dmaengine_prep_slave_sg(dma->chan_rx, sg,
+                                       num, DMA_DEV_TO_MEM,
+                                       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+       if (!desc_rx) {
+               dev_err(&data->master->dev,
+                       "%s:dmaengine_prep_slave_sg Failed\n", __func__);
+               return;
+       }
+       dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_FROM_DEVICE);
+       desc_rx->callback = pch_dma_rx_complete;
+       desc_rx->callback_param = data;
+       dma->nent = num;
+       dma->desc_rx = desc_rx;
+
+       /* Calculate Tx parameter for DMA transmitting */
+       if (data->bpw_len > PCH_MAX_FIFO_DEPTH) {
+               head = PCH_MAX_FIFO_DEPTH - PCH_DMA_TRANS_SIZE;
+               if (data->bpw_len % PCH_DMA_TRANS_SIZE > 4) {
+                       num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
+                       rem = data->bpw_len % PCH_DMA_TRANS_SIZE - head;
+               } else {
+                       num = data->bpw_len / PCH_DMA_TRANS_SIZE;
+                       rem = data->bpw_len % PCH_DMA_TRANS_SIZE +
+                             PCH_DMA_TRANS_SIZE - head;
+               }
+               size = PCH_DMA_TRANS_SIZE;
+       } else {
+               num = 1;
+               size = data->bpw_len;
+               rem = data->bpw_len;
+               head = 0;
+       }
+
+       dma->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
+       sg_init_table(dma->sg_tx_p, num); /* Initialize SG table */
+       /* offset, length setting */
+       sg = dma->sg_tx_p;
+       for (i = 0; i < num; i++, sg++) {
+               if (i == 0) {
+                       sg->offset = 0;
+                       sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size + head,
+                                   sg->offset);
+                       sg_dma_len(sg) = size + head;
+               } else if (i == (num - 1)) {
+                       sg->offset = head + size * i;
+                       sg->offset = sg->offset * (*bpw / 8);
+                       sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem,
+                                   sg->offset);
+                       sg_dma_len(sg) = rem;
+               } else {
+                       sg->offset = head + size * i;
+                       sg->offset = sg->offset * (*bpw / 8);
+                       sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size,
+                                   sg->offset);
+                       sg_dma_len(sg) = size;
+               }
+               sg_dma_address(sg) = dma->tx_buf_dma + sg->offset;
+       }
+       sg = dma->sg_tx_p;
+       desc_tx = dmaengine_prep_slave_sg(dma->chan_tx,
+                                       sg, num, DMA_MEM_TO_DEV,
+                                       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+       if (!desc_tx) {
+               dev_err(&data->master->dev,
+                       "%s:dmaengine_prep_slave_sg Failed\n", __func__);
+               return;
+       }
+       dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_TO_DEVICE);
+       desc_tx->callback = NULL;
+       desc_tx->callback_param = data;
+       dma->nent = num;
+       dma->desc_tx = desc_tx;
+
+       dev_dbg(&data->master->dev, "%s:Pulling down SSN low - writing 0x2 to SSNXCR\n", __func__);
+
+       spin_lock_irqsave(&data->lock, flags);
+       pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
+       desc_rx->tx_submit(desc_rx);
+       desc_tx->tx_submit(desc_tx);
+       spin_unlock_irqrestore(&data->lock, flags);
+
+       /* reset transfer complete flag */
+       data->transfer_complete = false;
+}
+
+static void pch_spi_process_messages(struct work_struct *pwork)
+{
+       struct spi_message *pmsg, *tmp;
+       struct pch_spi_data *data;
+       int bpw;
+
+       data = container_of(pwork, struct pch_spi_data, work);
+       dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
+
+       spin_lock(&data->lock);
+       /* check if suspend has been initiated;if yes flush queue */
+       if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
+               dev_dbg(&data->master->dev,
+                       "%s suspend/remove initiated, flushing queue\n", __func__);
+               list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
+                       pmsg->status = -EIO;
+
+                       if (pmsg->complete) {
+                               spin_unlock(&data->lock);
+                               pmsg->complete(pmsg->context);
+                               spin_lock(&data->lock);
+                       }
+
+                       /* delete from queue */
+                       list_del_init(&pmsg->queue);
+               }
+
+               spin_unlock(&data->lock);
+               return;
+       }
+
+       data->bcurrent_msg_processing = true;
+       dev_dbg(&data->master->dev,
+               "%s Set data->bcurrent_msg_processing= true\n", __func__);
+
+       /* Get the message from the queue and delete it from there. */
+       data->current_msg = list_entry(data->queue.next, struct spi_message,
+                                       queue);
+
+       list_del_init(&data->current_msg->queue);
+
+       data->current_msg->status = 0;
+
+       pch_spi_select_chip(data, data->current_msg->spi);
+
+       spin_unlock(&data->lock);
+
+       if (data->use_dma)
+               pch_spi_request_dma(data,
+                                   data->current_msg->spi->bits_per_word);
+       pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
+       do {
+               int cnt;
+               /* If we are already processing a message get the next
+               transfer structure from the message otherwise retrieve
+               the 1st transfer request from the message. */
+               spin_lock(&data->lock);
+               if (data->cur_trans == NULL) {
+                       data->cur_trans =
+                               list_entry(data->current_msg->transfers.next,
+                                          struct spi_transfer, transfer_list);
+                       dev_dbg(&data->master->dev, "%s "
+                               ":Getting 1st transfer message\n", __func__);
+               } else {
+                       data->cur_trans =
+                               list_entry(data->cur_trans->transfer_list.next,
+                                          struct spi_transfer, transfer_list);
+                       dev_dbg(&data->master->dev, "%s "
+                               ":Getting next transfer message\n", __func__);
+               }
+               spin_unlock(&data->lock);
+
+               if (!data->cur_trans->len)
+                       goto out;
+               cnt = (data->cur_trans->len - 1) / PCH_BUF_SIZE + 1;
+               data->save_total_len = data->cur_trans->len;
+               if (data->use_dma) {
+                       int i;
+                       char *save_rx_buf = data->cur_trans->rx_buf;
+                       for (i = 0; i < cnt; i ++) {
+                               pch_spi_handle_dma(data, &bpw);
+                               if (!pch_spi_start_transfer(data)) {
+                                       data->transfer_complete = true;
+                                       data->current_msg->status = -EIO;
+                                       data->current_msg->complete
+                                                  (data->current_msg->context);
+                                       data->bcurrent_msg_processing = false;
+                                       data->current_msg = NULL;
+                                       data->cur_trans = NULL;
+                                       goto out;
+                               }
+                               pch_spi_copy_rx_data_for_dma(data, bpw);
+                       }
+                       data->cur_trans->rx_buf = save_rx_buf;
+               } else {
+                       pch_spi_set_tx(data, &bpw);
+                       pch_spi_set_ir(data);
+                       pch_spi_copy_rx_data(data, bpw);
+                       kfree(data->pkt_rx_buff);
+                       data->pkt_rx_buff = NULL;
+                       kfree(data->pkt_tx_buff);
+                       data->pkt_tx_buff = NULL;
+               }
+               /* increment message count */
+               data->cur_trans->len = data->save_total_len;
+               data->current_msg->actual_length += data->cur_trans->len;
+
+               dev_dbg(&data->master->dev,
+                       "%s:data->current_msg->actual_length=%d\n",
+                       __func__, data->current_msg->actual_length);
+
+               /* check for delay */
+               if (data->cur_trans->delay_usecs) {
+                       dev_dbg(&data->master->dev, "%s:"
+                               "delay in usec=%d\n", __func__,
+                               data->cur_trans->delay_usecs);
+                       udelay(data->cur_trans->delay_usecs);
+               }
+
+               spin_lock(&data->lock);
+
+               /* No more transfer in this message. */
+               if ((data->cur_trans->transfer_list.next) ==
+                   &(data->current_msg->transfers)) {
+                       pch_spi_nomore_transfer(data);
+               }
+
+               spin_unlock(&data->lock);
+
+       } while (data->cur_trans != NULL);
+
+out:
+       pch_spi_writereg(data->master, PCH_SSNXCR, SSN_HIGH);
+       if (data->use_dma)
+               pch_spi_release_dma(data);
+}
+
+static void pch_spi_free_resources(struct pch_spi_board_data *board_dat,
+                                  struct pch_spi_data *data)
+{
+       dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
+
+       /* free workqueue */
+       if (data->wk != NULL) {
+               destroy_workqueue(data->wk);
+               data->wk = NULL;
+               dev_dbg(&board_dat->pdev->dev,
+                       "%s destroy_workqueue invoked successfully\n",
+                       __func__);
+       }
+}
+
+static int pch_spi_get_resources(struct pch_spi_board_data *board_dat,
+                                struct pch_spi_data *data)
+{
+       int retval = 0;
+
+       dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
+
+       /* create workqueue */
+       data->wk = create_singlethread_workqueue(KBUILD_MODNAME);
+       if (!data->wk) {
+               dev_err(&board_dat->pdev->dev,
+                       "%s create_singlet hread_workqueue failed\n", __func__);
+               retval = -EBUSY;
+               goto err_return;
+       }
+
+       /* reset PCH SPI h/w */
+       pch_spi_reset(data->master);
+       dev_dbg(&board_dat->pdev->dev,
+               "%s pch_spi_reset invoked successfully\n", __func__);
+
+       dev_dbg(&board_dat->pdev->dev, "%s data->irq_reg_sts=true\n", __func__);
+
+err_return:
+       if (retval != 0) {
+               dev_err(&board_dat->pdev->dev,
+                       "%s FAIL:invoking pch_spi_free_resources\n", __func__);
+               pch_spi_free_resources(board_dat, data);
+       }
+
+       dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval);
+
+       return retval;
+}
+
+static void pch_free_dma_buf(struct pch_spi_board_data *board_dat,
+                            struct pch_spi_data *data)
+{
+       struct pch_spi_dma_ctrl *dma;
+
+       dma = &data->dma;
+       if (dma->tx_buf_dma)
+               dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
+                                 dma->tx_buf_virt, dma->tx_buf_dma);
+       if (dma->rx_buf_dma)
+               dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
+                                 dma->rx_buf_virt, dma->rx_buf_dma);
+       return;
+}
+
+static void pch_alloc_dma_buf(struct pch_spi_board_data *board_dat,
+                             struct pch_spi_data *data)
+{
+       struct pch_spi_dma_ctrl *dma;
+
+       dma = &data->dma;
+       /* Get Consistent memory for Tx DMA */
+       dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
+                               PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL);
+       /* Get Consistent memory for Rx DMA */
+       dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
+                               PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL);
+}
+
+static int pch_spi_pd_probe(struct platform_device *plat_dev)
+{
+       int ret;
+       struct spi_master *master;
+       struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
+       struct pch_spi_data *data;
+
+       dev_dbg(&plat_dev->dev, "%s:debug\n", __func__);
+
+       master = spi_alloc_master(&board_dat->pdev->dev,
+                                 sizeof(struct pch_spi_data));
+       if (!master) {
+               dev_err(&plat_dev->dev, "spi_alloc_master[%d] failed.\n",
+                       plat_dev->id);
+               return -ENOMEM;
+       }
+
+       data = spi_master_get_devdata(master);
+       data->master = master;
+
+       platform_set_drvdata(plat_dev, data);
+
+       /* baseaddress + address offset) */
+       data->io_base_addr = pci_resource_start(board_dat->pdev, 1) +
+                                        PCH_ADDRESS_SIZE * plat_dev->id;
+       data->io_remap_addr = pci_iomap(board_dat->pdev, 1, 0);
+       if (!data->io_remap_addr) {
+               dev_err(&plat_dev->dev, "%s pci_iomap failed\n", __func__);
+               ret = -ENOMEM;
+               goto err_pci_iomap;
+       }
+       data->io_remap_addr += PCH_ADDRESS_SIZE * plat_dev->id;
+
+       dev_dbg(&plat_dev->dev, "[ch%d] remap_addr=%p\n",
+               plat_dev->id, data->io_remap_addr);
+
+       /* initialize members of SPI master */
+       master->num_chipselect = PCH_MAX_CS;
+       master->transfer = pch_spi_transfer;
+       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+       master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
+       master->max_speed_hz = PCH_MAX_BAUDRATE;
+
+       data->board_dat = board_dat;
+       data->plat_dev = plat_dev;
+       data->n_curnt_chip = 255;
+       data->status = STATUS_RUNNING;
+       data->ch = plat_dev->id;
+       data->use_dma = use_dma;
+
+       INIT_LIST_HEAD(&data->queue);
+       spin_lock_init(&data->lock);
+       INIT_WORK(&data->work, pch_spi_process_messages);
+       init_waitqueue_head(&data->wait);
+
+       ret = pch_spi_get_resources(board_dat, data);
+       if (ret) {
+               dev_err(&plat_dev->dev, "%s fail(retval=%d)\n", __func__, ret);
+               goto err_spi_get_resources;
+       }
+
+       ret = request_irq(board_dat->pdev->irq, pch_spi_handler,
+                         IRQF_SHARED, KBUILD_MODNAME, data);
+       if (ret) {
+               dev_err(&plat_dev->dev,
+                       "%s request_irq failed\n", __func__);
+               goto err_request_irq;
+       }
+       data->irq_reg_sts = true;
+
+       pch_spi_set_master_mode(master);
+
+       if (use_dma) {
+               dev_info(&plat_dev->dev, "Use DMA for data transfers\n");
+               pch_alloc_dma_buf(board_dat, data);
+       }
+
+       ret = spi_register_master(master);
+       if (ret != 0) {
+               dev_err(&plat_dev->dev,
+                       "%s spi_register_master FAILED\n", __func__);
+               goto err_spi_register_master;
+       }
+
+       return 0;
+
+err_spi_register_master:
+       pch_free_dma_buf(board_dat, data);
+       free_irq(board_dat->pdev->irq, data);
+err_request_irq:
+       pch_spi_free_resources(board_dat, data);
+err_spi_get_resources:
+       pci_iounmap(board_dat->pdev, data->io_remap_addr);
+err_pci_iomap:
+       spi_master_put(master);
+
+       return ret;
+}
+
+static int pch_spi_pd_remove(struct platform_device *plat_dev)
+{
+       struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
+       struct pch_spi_data *data = platform_get_drvdata(plat_dev);
+       int count;
+       unsigned long flags;
+
+       dev_dbg(&plat_dev->dev, "%s:[ch%d] irq=%d\n",
+               __func__, plat_dev->id, board_dat->pdev->irq);
+
+       if (use_dma)
+               pch_free_dma_buf(board_dat, data);
+
+       /* check for any pending messages; no action is taken if the queue
+        * is still full; but at least we tried.  Unload anyway */
+       count = 500;
+       spin_lock_irqsave(&data->lock, flags);
+       data->status = STATUS_EXITING;
+       while ((list_empty(&data->queue) == 0) && --count) {
+               dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
+                       __func__);
+               spin_unlock_irqrestore(&data->lock, flags);
+               msleep(PCH_SLEEP_TIME);
+               spin_lock_irqsave(&data->lock, flags);
+       }
+       spin_unlock_irqrestore(&data->lock, flags);
+
+       pch_spi_free_resources(board_dat, data);
+       /* disable interrupts & free IRQ */
+       if (data->irq_reg_sts) {
+               /* disable interrupts */
+               pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
+               data->irq_reg_sts = false;
+               free_irq(board_dat->pdev->irq, data);
+       }
+
+       pci_iounmap(board_dat->pdev, data->io_remap_addr);
+       spi_unregister_master(data->master);
+
+       return 0;
+}
+#ifdef CONFIG_PM
+static int pch_spi_pd_suspend(struct platform_device *pd_dev,
+                             pm_message_t state)
+{
+       u8 count;
+       struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
+       struct pch_spi_data *data = platform_get_drvdata(pd_dev);
+
+       dev_dbg(&pd_dev->dev, "%s ENTRY\n", __func__);
+
+       if (!board_dat) {
+               dev_err(&pd_dev->dev,
+                       "%s pci_get_drvdata returned NULL\n", __func__);
+               return -EFAULT;
+       }
+
+       /* check if the current message is processed:
+          Only after thats done the transfer will be suspended */
+       count = 255;
+       while ((--count) > 0) {
+               if (!(data->bcurrent_msg_processing))
+                       break;
+               msleep(PCH_SLEEP_TIME);
+       }
+
+       /* Free IRQ */
+       if (data->irq_reg_sts) {
+               /* disable all interrupts */
+               pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
+               pch_spi_reset(data->master);
+               free_irq(board_dat->pdev->irq, data);
+
+               data->irq_reg_sts = false;
+               dev_dbg(&pd_dev->dev,
+                       "%s free_irq invoked successfully.\n", __func__);
+       }
+
+       return 0;
+}
+
+static int pch_spi_pd_resume(struct platform_device *pd_dev)
+{
+       struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
+       struct pch_spi_data *data = platform_get_drvdata(pd_dev);
+       int retval;
+
+       if (!board_dat) {
+               dev_err(&pd_dev->dev,
+                       "%s pci_get_drvdata returned NULL\n", __func__);
+               return -EFAULT;
+       }
+
+       if (!data->irq_reg_sts) {
+               /* register IRQ */
+               retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
+                                    IRQF_SHARED, KBUILD_MODNAME, data);
+               if (retval < 0) {
+                       dev_err(&pd_dev->dev,
+                               "%s request_irq failed\n", __func__);
+                       return retval;
+               }
+
+               /* reset PCH SPI h/w */
+               pch_spi_reset(data->master);
+               pch_spi_set_master_mode(data->master);
+               data->irq_reg_sts = true;
+       }
+       return 0;
+}
+#else
+#define pch_spi_pd_suspend NULL
+#define pch_spi_pd_resume NULL
+#endif
+
+static struct platform_driver pch_spi_pd_driver = {
+       .driver = {
+               .name = "pch-spi",
+       },
+       .probe = pch_spi_pd_probe,
+       .remove = pch_spi_pd_remove,
+       .suspend = pch_spi_pd_suspend,
+       .resume = pch_spi_pd_resume
+};
+
+static int pch_spi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+       struct pch_spi_board_data *board_dat;
+       struct platform_device *pd_dev = NULL;
+       int retval;
+       int i;
+       struct pch_pd_dev_save *pd_dev_save;
+
+       pd_dev_save = kzalloc(sizeof(struct pch_pd_dev_save), GFP_KERNEL);
+       if (!pd_dev_save)
+               return -ENOMEM;
+
+       board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL);
+       if (!board_dat) {
+               retval = -ENOMEM;
+               goto err_no_mem;
+       }
+
+       retval = pci_request_regions(pdev, KBUILD_MODNAME);
+       if (retval) {
+               dev_err(&pdev->dev, "%s request_region failed\n", __func__);
+               goto pci_request_regions;
+       }
+
+       board_dat->pdev = pdev;
+       board_dat->num = id->driver_data;
+       pd_dev_save->num = id->driver_data;
+       pd_dev_save->board_dat = board_dat;
+
+       retval = pci_enable_device(pdev);
+       if (retval) {
+               dev_err(&pdev->dev, "%s pci_enable_device failed\n", __func__);
+               goto pci_enable_device;
+       }
+
+       for (i = 0; i < board_dat->num; i++) {
+               pd_dev = platform_device_alloc("pch-spi", i);
+               if (!pd_dev) {
+                       dev_err(&pdev->dev, "platform_device_alloc failed\n");
+                       retval = -ENOMEM;
+                       goto err_platform_device;
+               }
+               pd_dev_save->pd_save[i] = pd_dev;
+               pd_dev->dev.parent = &pdev->dev;
+
+               retval = platform_device_add_data(pd_dev, board_dat,
+                                                 sizeof(*board_dat));
+               if (retval) {
+                       dev_err(&pdev->dev,
+                               "platform_device_add_data failed\n");
+                       platform_device_put(pd_dev);
+                       goto err_platform_device;
+               }
+
+               retval = platform_device_add(pd_dev);
+               if (retval) {
+                       dev_err(&pdev->dev, "platform_device_add failed\n");
+                       platform_device_put(pd_dev);
+                       goto err_platform_device;
+               }
+       }
+
+       pci_set_drvdata(pdev, pd_dev_save);
+
+       return 0;
+
+err_platform_device:
+       while (--i >= 0)
+               platform_device_unregister(pd_dev_save->pd_save[i]);
+       pci_disable_device(pdev);
+pci_enable_device:
+       pci_release_regions(pdev);
+pci_request_regions:
+       kfree(board_dat);
+err_no_mem:
+       kfree(pd_dev_save);
+
+       return retval;
+}
+
+static void pch_spi_remove(struct pci_dev *pdev)
+{
+       int i;
+       struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
+
+       dev_dbg(&pdev->dev, "%s ENTRY:pdev=%p\n", __func__, pdev);
+
+       for (i = 0; i < pd_dev_save->num; i++)
+               platform_device_unregister(pd_dev_save->pd_save[i]);
+
+       pci_disable_device(pdev);
+       pci_release_regions(pdev);
+       kfree(pd_dev_save->board_dat);
+       kfree(pd_dev_save);
+}
+
+#ifdef CONFIG_PM
+static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+       int retval;
+       struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
+
+       dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+       pd_dev_save->board_dat->suspend_sts = true;
+
+       /* save config space */
+       retval = pci_save_state(pdev);
+       if (retval == 0) {
+               pci_enable_wake(pdev, PCI_D3hot, 0);
+               pci_disable_device(pdev);
+               pci_set_power_state(pdev, PCI_D3hot);
+       } else {
+               dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__);
+       }
+
+       return retval;
+}
+
+static int pch_spi_resume(struct pci_dev *pdev)
+{
+       int retval;
+       struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
+       dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+       pci_set_power_state(pdev, PCI_D0);
+       pci_restore_state(pdev);
+
+       retval = pci_enable_device(pdev);
+       if (retval < 0) {
+               dev_err(&pdev->dev,
+                       "%s pci_enable_device failed\n", __func__);
+       } else {
+               pci_enable_wake(pdev, PCI_D3hot, 0);
+
+               /* set suspend status to false */
+               pd_dev_save->board_dat->suspend_sts = false;
+       }
+
+       return retval;
+}
+#else
+#define pch_spi_suspend NULL
+#define pch_spi_resume NULL
+
+#endif
+
+static struct pci_driver pch_spi_pcidev_driver = {
+       .name = "pch_spi",
+       .id_table = pch_spi_pcidev_id,
+       .probe = pch_spi_probe,
+       .remove = pch_spi_remove,
+       .suspend = pch_spi_suspend,
+       .resume = pch_spi_resume,
+};
+
+static int __init pch_spi_init(void)
+{
+       int ret;
+       ret = platform_driver_register(&pch_spi_pd_driver);
+       if (ret)
+               return ret;
+
+       ret = pci_register_driver(&pch_spi_pcidev_driver);
+       if (ret) {
+               platform_driver_unregister(&pch_spi_pd_driver);
+               return ret;
+       }
+
+       return 0;
+}
+module_init(pch_spi_init);
+
+static void __exit pch_spi_exit(void)
+{
+       pci_unregister_driver(&pch_spi_pcidev_driver);
+       platform_driver_unregister(&pch_spi_pd_driver);
+}
+module_exit(pch_spi_exit);
+
+module_param(use_dma, int, 0644);
+MODULE_PARM_DESC(use_dma,
+                "to use DMA for data transfers pass 1 else 0; default 1");
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semiconductor ML7xxx IOH SPI Driver");
+MODULE_DEVICE_TABLE(pci, pch_spi_pcidev_id);
+