Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1704 insertions, 0 deletions

diff --git a/drivers/spi/spi-topcliff-pch.c b/drivers/spi/spi-topcliff-pch.c
new file mode 100644
index 000000000..7fb020a1d
--- /dev/null
+++ b/drivers/spi/spi-topcliff-pch.c
@@ -0,0 +1,1704 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SPI bus driver for the Topcliff PCH used by Intel SoCs
+ *
+ * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
+ */
+
+#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_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
+ * @io_base_addr:		Base address
+ * @master:			Pointer to the SPI master structure
+ * @work:			Reference to work queue handler
+ * @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
+ * @pkt_tx_buff:		Buffer for data to be transmitted
+ * @pkt_rx_buff:		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
+ * @dma:			Local DMA information
+ * @use_dma:			True if DMA is to be used
+ * @irq_reg_sts:		Status of IRQ registration
+ * @save_total_len:		Save length while data is being transferred
+ */
+struct pch_spi_data {
+	void __iomem *io_remap_addr;
+	unsigned long io_base_addr;
+	struct spi_master *master;
+	struct work_struct work;
+	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(&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);
+			data->pkt_tx_buff = NULL;
+		}
+	}
+
+	if (!data->pkt_rx_buff) {
+		/* flush queue and set status of all transfers to -ENOMEM */
+		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__);
+		schedule_work(&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;
+	}
+}
+
+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 = kmalloc_array(num, sizeof(*dma->sg_rx_p), GFP_ATOMIC);
+	if (!dma->sg_rx_p)
+		return;
+
+	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 = kmalloc_array(num, sizeof(*dma->sg_tx_p), GFP_ATOMIC);
+	if (!dma->sg_tx_p)
+		return;
+
+	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);
+
+		spi_transfer_delay_exec(data->cur_trans);
+
+		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__);
+
+	flush_work(&data->work);
+}
+
+static int pch_spi_get_resources(struct pch_spi_board_data *board_dat,
+				 struct pch_spi_data *data)
+{
+	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
+
+	/* 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__);
+
+	return 0;
+}
+
+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);
+}
+
+static int pch_alloc_dma_buf(struct pch_spi_board_data *board_dat,
+			      struct pch_spi_data *data)
+{
+	struct pch_spi_dma_ctrl *dma;
+	int ret;
+
+	dma = &data->dma;
+	ret = 0;
+	/* 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);
+	if (!dma->tx_buf_virt)
+		ret = -ENOMEM;
+
+	/* 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);
+	if (!dma->rx_buf_virt)
+		ret = -ENOMEM;
+
+	return ret;
+}
+
+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");
+		ret = pch_alloc_dma_buf(board_dat, data);
+		if (ret)
+			goto err_spi_register_master;
+	}
+
+	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(*pd_dev_save), GFP_KERNEL);
+	if (!pd_dev_save)
+		return -ENOMEM;
+
+	board_dat = kzalloc(sizeof(*board_dat), 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);
+}
+
+static int __maybe_unused pch_spi_suspend(struct device *dev)
+{
+	struct pch_pd_dev_save *pd_dev_save = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "%s ENTRY\n", __func__);
+
+	pd_dev_save->board_dat->suspend_sts = true;
+
+	return 0;
+}
+
+static int __maybe_unused pch_spi_resume(struct device *dev)
+{
+	struct pch_pd_dev_save *pd_dev_save = dev_get_drvdata(dev);
+
+	dev_dbg(dev, "%s ENTRY\n", __func__);
+
+	/* set suspend status to false */
+	pd_dev_save->board_dat->suspend_sts = false;
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(pch_spi_pm_ops, pch_spi_suspend, pch_spi_resume);
+
+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,
+	.driver.pm = &pch_spi_pm_ops,
+};
+
+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);
+