spi/topcliff: Add topcliff platform controller hub (PCH) spi bus driver

Topcliff PCH is the platform controller hub that is going to be used
in Intel's upcoming general embedded platform. All IO peripherals in
Topcliff PCH are actually devices sitting on AMBA bus.  This patch
adds a driver for the SPI bus integrated into the Topcliff device.

Signed-off-by: Masayuki Ohtake <masa-korg@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 1529 insertions, 0 deletions

diff --git a/drivers/spi/spi_topcliff_pch.c b/drivers/spi/spi_topcliff_pch.c
new file mode 100644
index 000000000000..58b183f6eec0
--- /dev/null
+++ b/drivers/spi/spi_topcliff_pch.c
@@ -0,0 +1,1529 @@
+/*
+ * SPI bus driver for the Topcliff PCH used by Intel SoCs
+ */
+
+/*
+ * Copyright (C) 2010 OKI 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#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>
+
+/* 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_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_RX			1
+#define PCH_TX			2
+
+/* various interrupts */
+#define PCH_TFI			0x1
+#define PCH_RFI			0x2
+#define PCH_FI			0x4
+#define PCH_ORI			0x8
+#define PCH_MDFI		0x10
+
+#define PCH_ALL			(PCH_TFI|PCH_RFI|PCH_FI|PCH_ORI|PCH_MDFI)
+#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 PCH_ADDRESS_SIZE	0x20
+
+#define SSN_LOW			0x02U
+#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 SPBRR_SIZE_BIT		(1 << 10)
+
+#define SPCR_RFIC_FIELD		20
+#define SPCR_TFIC_FIELD		16
+
+#define SPSR_INT_BITS		0x1F
+#define MASK_SPBRR_SPBR_BITS	(~((1 << 10) - 1))
+#define MASK_RFIC_SPCR_BITS	(~(0xf << 20))
+#define MASK_TFIC_SPCR_BITS	(~(0xf000f << 12))
+
+#define PCH_CLOCK_HZ		50000000
+#define PCH_MAX_SPBR		1023
+
+
+/**
+ * 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
+ */
+struct pch_spi_data {
+	void __iomem *io_remap_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 pch_spi_board_data - Holds the SPI device specific details
+ * @pdev:		Pointer to the PCI device
+ * @irq_reg_sts:	Status of IRQ registration
+ * @pci_req_sts:	Status of pci_request_regions
+ * @suspend_sts:	Status of suspend
+ * @data:		Pointer to SPI channel data structure
+ */
+struct pch_spi_board_data {
+	struct pci_dev *pdev;
+	u8 irq_reg_sts;
+	u8 pci_req_sts;
+	u8 suspend_sts;
+	struct pch_spi_data *data;
+};
+
+static struct pci_device_id pch_spi_pcidev_id[] = {
+	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_GE_SPI)},
+	{0,}
+};
+
+static inline void pch_set_bitmsk(u32 *var, u32 bitmask)
+{
+	*var |= bitmask;
+}
+
+static inline void pch_clr_bitmsk(u32 *var, u32 bitmask)
+{
+	*var &= (~(bitmask));
+}
+
+/**
+ * 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);
+}
+
+/* ope==true:Set bit, ope==false:Clear bit */
+static inline void pch_spi_setclr_bit(u32 *val, u32 pos, bool ope)
+{
+	if (ope)
+		*val |= pos;
+	else
+		*val &= (~(pos));
+}
+
+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);
+}
+
+/**
+ * ch_spi_disable_interrupts() - Disables specified interrupts
+ * @master:	Pointer to struct spi_master.
+ * @interrupt:	Interrups to be enabled.
+ */
+static void pch_spi_disable_interrupts(struct spi_master *master, u8 interrupt)
+{
+	u32 clr_flags = 0;
+
+	if (interrupt & PCH_RFI)
+		clr_flags |= SPCR_RFIE_BIT;
+
+	if (interrupt & PCH_TFI)
+		clr_flags |= SPCR_TFIE_BIT;
+
+	if (interrupt & PCH_FI)
+		clr_flags |= SPCR_FIE_BIT;
+
+	if (interrupt & PCH_ORI)
+		clr_flags |= SPCR_ORIE_BIT;
+
+	if (interrupt & PCH_MDFI)
+		clr_flags |= SPCR_MDFIE_BIT;
+
+	pch_spi_setclr_reg(master, PCH_SPCR, 0, clr_flags);
+
+	dev_dbg(&master->dev, "%s clearing bits =%x\n", __func__, clr_flags);
+}
+
+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);
+
+			/* disable RFI */
+			pch_clr_bitmsk(&reg_spcr_val, SPCR_RFIE_BIT);
+
+			/* reset rx threshold */
+			reg_spcr_val &= MASK_RFIC_SPCR_BITS;
+			reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
+			iowrite32(((reg_spcr_val) &= (~(SPCR_RFIE_BIT))),
+				 (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) {
+		/* disable FI & RFI interrupts */
+		pch_spi_disable_interrupts(data->master, PCH_FI | PCH_RFI);
+
+		/* transfer is completed;inform pch_spi_process_messages */
+		data->transfer_complete = true;
+		wake_up(&data->wait);
+	}
+}
+
+
+/**
+ * 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;
+	struct pch_spi_data *data;
+	void __iomem *spsr;
+	void __iomem *io_remap_addr;
+	irqreturn_t ret = IRQ_NONE;
+
+	struct pch_spi_board_data *board_dat = dev_id;
+
+	if (board_dat->suspend_sts) {
+		dev_dbg(&board_dat->pdev->dev,
+			"%s returning due to suspend\n", __func__);
+		return IRQ_NONE;
+	}
+
+	data = board_dat->data;
+	io_remap_addr = data->io_remap_addr;
+	spsr = io_remap_addr + PCH_SPSR;
+
+	reg_spsr_val = ioread32(spsr);
+
+	/* 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;
+
+	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 reg_spcr_val;
+
+	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)
+		pch_spi_setclr_reg(spi->master, PCH_SPCR, 0, SPCR_LSBF_BIT);
+	else
+		pch_spi_setclr_reg(spi->master, PCH_SPCR, SPCR_LSBF_BIT, 0);
+
+	if (spi->mode & SPI_CPOL)
+		pch_spi_setclr_reg(spi->master, PCH_SPCR, SPCR_CPOL_BIT, 0);
+	else
+		pch_spi_setclr_reg(spi->master, PCH_SPCR, 0, SPCR_CPOL_BIT);
+
+	if (spi->mode & SPI_CPHA)
+		pch_spi_setclr_reg(spi->master, PCH_SPCR, SPCR_CPHA_BIT, 0);
+	else
+		pch_spi_setclr_reg(spi->master, PCH_SPCR, 0, SPCR_CPHA_BIT);
+
+	dev_dbg(&spi->dev,
+		"%s SPCR content after setting LSB/MSB and MODE= %x\n",
+		__func__, reg_spcr_val);
+
+	/* Clear the FIFO by toggling  FICLR to 1 and back to 0 */
+	pch_spi_clear_fifo(spi->master);
+}
+
+/**
+ * pch_spi_enable_interrupts() - Enables specified interrupts
+ * @master:	Pointer to struct spi_master.
+ * @interrupt:	Interrups to be enabled.
+ */
+static void pch_spi_enable_interrupts(struct spi_master *master, u8 interrupt)
+{
+	u32 reg_val_spcr;
+
+	dev_dbg(&master->dev, "%s SPCR content=%x\n", __func__, reg_val_spcr);
+
+	if (interrupt & PCH_RFI) {
+		/* set RFIE bit in SPCR */
+		dev_dbg(&master->dev, "setting RFI in %s\n", __func__);
+		pch_spi_setclr_reg(master, PCH_SPCR, SPCR_RFIE_BIT, 0);
+	}
+
+	if (interrupt & PCH_TFI) {
+		/* set TFIE bit in SPCR */
+		dev_dbg(&master->dev, "setting TFI in %s\n", __func__);
+		pch_spi_setclr_reg(master, PCH_SPCR, SPCR_TFIE_BIT, 0);
+	}
+
+	if (interrupt & PCH_FI) {
+		/* set FIE bit in SPCR */
+		dev_dbg(&master->dev, "setting FI in %s\n", __func__);
+		pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FIE_BIT, 0);
+	}
+
+	if (interrupt & PCH_ORI) {
+		/* set ORIE bit in SPCR */
+		dev_dbg(&master->dev, "setting ORI in %s\n", __func__);
+		pch_spi_setclr_reg(master, PCH_SPCR, SPCR_ORIE_BIT, 0);
+	}
+
+	if (interrupt & PCH_MDFI) {
+		/* set MODFIE bit in SPCR */
+		dev_dbg(&master->dev, "setting MDFI in %s\n", __func__);
+		pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MDFIE_BIT, 0);
+	}
+}
+
+/**
+ * pch_spi_set_threshold() - Sets Tx/Rx FIFO thresholds
+ * @spi:	Pointer to struct spi_device.
+ * @threshold:	Threshold value to be set.
+ * @dir:	Rx or Tx threshold to be set.
+ */
+static void pch_spi_set_threshold(struct spi_device *spi, u32 threshold, u8 dir)
+{
+
+	if (dir == PCH_RX) {
+		dev_dbg(&spi->dev, "%s setting Rx threshold\n", __func__);
+		pch_spi_setclr_reg(spi->master, PCH_SPCR,
+				   threshold << SPCR_RFIC_FIELD,
+				   ~MASK_RFIC_SPCR_BITS);
+
+	} else if (dir == PCH_TX) {
+		dev_dbg(&spi->dev, "%s setting Tx threshold\n",  __func__);
+		pch_spi_setclr_reg(spi->master, PCH_SPCR,
+				  (threshold << SPCR_TFIC_FIELD) ,
+				   ~MASK_TFIC_SPCR_BITS);
+	}
+}
+
+/**
+ * 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_setup(struct spi_device *pspi)
+{
+	/* check bits per word */
+	if ((pspi->bits_per_word) == 0) {
+		pspi->bits_per_word = 8;
+		dev_dbg(&pspi->dev, "%s 8 bits per word\n", __func__);
+	}
+
+	if (((pspi->bits_per_word) != 8) &&
+	    ((pspi->bits_per_word != 16))) {
+		dev_err(&pspi->dev, "%s Invalid bits per word\n", __func__);
+		return -EINVAL;
+	}
+
+	/* Check baud rate setting */
+	/* if baud rate of chip is greater than
+	   max we can support,return error */
+	if ((pspi->max_speed_hz) > PCH_MAX_BAUDRATE)
+		pspi->max_speed_hz = PCH_MAX_BAUDRATE;
+
+	dev_dbg(&pspi->dev, "%s MODE = %x\n", __func__,
+		((pspi->mode) & (SPI_CPOL | SPI_CPHA)));
+
+	return 0;
+}
+
+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;
+
+	/* validate spi message and baud rate */
+	if (unlikely((list_empty(&pmsg->transfers) == 1) ||
+		     (pspi->max_speed_hz == 0))) {
+		if (list_empty(&pmsg->transfers) == 1)
+			dev_err(&pspi->dev, "%s list empty\n", __func__);
+
+		if ((pspi->max_speed_hz) == 0) {
+			dev_err(&pspi->dev, "%s pch_spi_tranfer maxspeed=%d\n",
+				__func__, pspi->max_speed_hz);
+		}
+		dev_err(&pspi->dev, "%s returning EINVAL\n", __func__);
+
+		retval = -EINVAL;
+		goto err_out;
+	}
+
+	dev_dbg(&pspi->dev, "%s Transfer List not empty. "
+		"Transfer Speed is set.\n", __func__);
+
+	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__);
+
+		/* if baud rate hs been specified validate the same */
+		if (transfer->speed_hz) {
+			if ((transfer->speed_hz) > PCH_MAX_BAUDRATE)
+				transfer->speed_hz = PCH_MAX_BAUDRATE;
+		}
+
+		/* if bits per word has been specified validate the same */
+		if (transfer->bits_per_word) {
+			if ((transfer->bits_per_word != 8)
+			    && (transfer->bits_per_word != 16)) {
+				retval = -EINVAL;
+				dev_err(&pspi->dev,
+					"%s Invalid bits per word\n", __func__);
+				goto err_return_spinlock;
+			}
+		}
+	}
+
+	/* We won't process any messages if we have been asked to terminate */
+
+	if (STATUS_EXITING == (data->status)) {
+		dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
+		retval = -ESHUTDOWN;
+		goto err_return_spinlock;
+	}
+
+	/* If suspended ,return -EINVAL */
+	if (data->board_dat->suspend_sts) {
+		dev_err(&pspi->dev,
+			"%s bSuspending= true returning EINVAL\n", __func__);
+		retval = -EINVAL;
+		goto err_return_spinlock;
+	}
+
+	/* set status of message */
+	pmsg->actual_length = 0;
+
+	dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
+
+	pmsg->status = -EINPROGRESS;
+
+	/* add message to queue */
+	list_add_tail(&pmsg->queue, &data->queue);
+
+	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_return_spinlock:
+	spin_unlock_irqrestore(&data->lock, flags);
+err_out:
+	dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
+	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-Invoking\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,
+						struct spi_message **ppmsg)
+{
+	int b_mem_fail;
+	int size;
+	u32 n_writes;
+	int j;
+	struct spi_message *pmsg;
+	const u8 *tx_buf;
+	const u16 *tx_sbuf;
+
+	pmsg = *ppmsg;
+
+	/* set baud rate if needed */
+	if (data->cur_trans->speed_hz) {
+		dev_dbg(&data->master->dev,
+			"%s:pctrldatasetting 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:setting 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);
+	b_mem_fail = false;
+
+	/* 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 == NULL) {
+			b_mem_fail = true;
+			kfree(data->pkt_tx_buff);
+		}
+	} else {
+		b_mem_fail = true;
+	}
+
+	if (b_mem_fail) {
+		/* flush queue and set status of all transfers to -ENOMEM */
+		dev_err(&data->master->dev,
+			"Kzalloc fail in %s messages\n", __func__);
+		list_for_each_entry(pmsg, data->queue.next, queue) {
+			pmsg->status = -ENOMEM;
+
+			if (pmsg->complete != 0)
+				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) {
+			for (j = 0; j < (data->bpw_len); j++) {
+				tx_buf = data->cur_trans->tx_buf;
+				data->pkt_tx_buff[j] = tx_buf[j];
+			}
+		} else {
+			for (j = 0; j < (data->bpw_len); j++) {
+				tx_sbuf = data->cur_trans->tx_buf;
+				data->pkt_tx_buff[j] = tx_sbuf[j];
+			}
+		}
+	}
+
+	/* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
+	if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
+		n_writes = PCH_MAX_FIFO_DEPTH;
+	else
+		n_writes = (data->bpw_len);
+
+	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)
+{
+	dev_dbg(&data->master->dev,
+		"%s:no more transfers in this message\n", __func__);
+	/* Invoke complete callback
+	 [To the spi core..indicating end of transfer] */
+	data->current_msg->status = 0;
+
+	if ((data->current_msg->complete) != 0) {
+		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:we have pending messages-Invoking 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(pmsg, data->queue.next, queue) {
+			pmsg->status = -EIO;
+
+			if (pmsg->complete != 0)
+				pmsg->complete(pmsg->context);
+
+			/* delete from queue */
+			list_del_init(&pmsg->queue);
+		}
+	}
+}
+
+static void pch_spi_set_ir(struct pch_spi_data *data)
+{
+	u32 reg_spcr_val;
+
+	/* enable interrupts */
+	if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) {
+		/* set receive threhold to PCH_RX_THOLD */
+		pch_spi_set_threshold(data->current_chip, PCH_RX_THOLD, PCH_RX);
+		/* enable FI and RFI interrupts */
+		pch_spi_enable_interrupts(data->master, PCH_RFI | PCH_FI);
+	} else {
+		/* set receive threhold to maximum */
+		pch_spi_set_threshold(data->current_chip, PCH_RX_THOLD_MAX,
+				      PCH_RX);
+		/* enable FI interrupt */
+		pch_spi_enable_interrupts(data->master, PCH_FI);
+	}
+
+	dev_dbg(&data->master->dev,
+		"%s:invoking pch_spi_set_enable to enable SPI\n", __func__);
+
+	/* SPI set enable */
+	reg_spcr_val = pch_spi_readreg(data->current_chip->master, PCH_SPCR);
+	pch_set_bitmsk(&reg_spcr_val, SPCR_SPE_BIT);
+	pch_spi_writereg(data->current_chip->master, PCH_SPCR, reg_spcr_val);
+
+
+	/* 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);
+
+	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
+	dev_dbg(&data->master->dev,
+		"%s:no more control over SSN-writing 0 to SSNXCR.", __func__);
+
+	data->transfer_active = false;
+	dev_dbg(&data->master->dev,
+		"%s set data->transfer_active = false\n", __func__);
+
+	/* clear all interrupts */
+	pch_spi_writereg(data->master, PCH_SPSR,
+			 (pch_spi_readreg(data->master, PCH_SPSR)));
+	/* disable interrupts */
+	pch_spi_disable_interrupts(data->master, PCH_ALL);
+}
+
+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) {
+		for (j = 0; j < (data->bpw_len); j++) {
+			rx_buf = data->cur_trans->rx_buf;
+			rx_buf[j] = (data->pkt_rx_buff[j]) & 0xFF;
+		}
+	} else {
+		for (j = 0; j < (data->bpw_len); j++) {
+			rx_sbuf = data->cur_trans->rx_buf;
+			rx_sbuf[j] = data->pkt_rx_buff[j];
+		}
+	}
+}
+
+
+static void pch_spi_process_messages(struct work_struct *pwork)
+{
+	struct spi_message *pmsg;
+	int bpw;
+
+	struct pch_spi_data *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(pmsg, data->queue.next, queue) {
+			pmsg->status = -EIO;
+
+			if (pmsg->complete != 0) {
+				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);
+
+	do {
+		/* 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);
+
+		pch_spi_set_tx(data, &bpw, &pmsg);
+
+		/* Control interrupt*/
+		pch_spi_set_ir(data);
+
+		/* Disable SPI transfer */
+		pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, 0,
+				   SPCR_SPE_BIT);
+
+		/* clear FIFO */
+		pch_spi_clear_fifo(data->master);
+
+		/* copy Rx Data */
+		pch_spi_copy_rx_data(data, bpw);
+
+		/* free memory */
+		kfree(data->pkt_rx_buff);
+		data->pkt_rx_buff = NULL;
+
+		kfree(data->pkt_tx_buff);
+		data->pkt_tx_buff = NULL;
+
+		/* increment message count */
+		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, pmsg);
+		}
+
+		spin_unlock(&data->lock);
+
+	} while ((data->cur_trans) != NULL);
+}
+
+static void pch_spi_free_resources(struct pch_spi_board_data *board_dat)
+{
+	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
+
+	/* free workqueue */
+	if (board_dat->data->wk != NULL) {
+		destroy_workqueue(board_dat->data->wk);
+		board_dat->data->wk = NULL;
+		dev_dbg(&board_dat->pdev->dev,
+			"%s destroy_workqueue invoked successfully\n",
+			__func__);
+	}
+
+	/* disable interrupts & free IRQ */
+	if (board_dat->irq_reg_sts) {
+		/* disable interrupts */
+		pch_spi_disable_interrupts(board_dat->data->
+					   master, PCH_ALL);
+		dev_dbg(&board_dat->pdev->dev,
+			"%s pch_spi_disable_interrupts invoked "
+			"successfully\n", __func__);
+
+		/* free IRQ */
+		free_irq(board_dat->pdev->irq, (void *)board_dat);
+
+		dev_dbg(&board_dat->pdev->dev,
+			"%s free_irq invoked successfully\n", __func__);
+
+		board_dat->irq_reg_sts = false;
+	}
+
+	/* unmap PCI base address */
+	if ((board_dat->data->io_remap_addr) != 0) {
+		pci_iounmap(board_dat->pdev, board_dat->data->io_remap_addr);
+
+		board_dat->data->io_remap_addr = 0;
+
+		dev_dbg(&board_dat->pdev->dev,
+			"%s pci_iounmap invoked successfully\n", __func__);
+	}
+
+	/* release PCI region */
+	if (board_dat->pci_req_sts) {
+		pci_release_regions(board_dat->pdev);
+		dev_dbg(&board_dat->pdev->dev,
+			"%s pci_release_regions invoked successfully\n",
+			__func__);
+		board_dat->pci_req_sts = false;
+	}
+}
+
+static int pch_spi_get_resources(struct pch_spi_board_data *board_dat)
+{
+	void __iomem *io_remap_addr;
+	int retval;
+	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
+
+	/* iniatize queue of pending messages */
+	INIT_LIST_HEAD(&(board_dat->data->queue));
+
+	/* initialize spin locks */
+	spin_lock_init(&(board_dat->data->lock));
+
+	/* set channel status */
+	board_dat->data->status = STATUS_RUNNING;
+
+	/* initialize work structure */
+	INIT_WORK(&(board_dat->data->work),
+		  pch_spi_process_messages);
+
+	/* initialize wait queues */
+	init_waitqueue_head(&(board_dat->data->wait));
+
+	/* create workqueue */
+	board_dat->data->wk = create_singlethread_workqueue(KBUILD_MODNAME);
+
+	if ((board_dat->data->wk) == NULL) {
+		dev_err(&board_dat->pdev->dev,
+			"%s create_singlet hread_workqueue failed\n", __func__);
+		retval = -EBUSY;
+		goto err_return;
+	}
+
+	dev_dbg(&board_dat->pdev->dev,
+		"%s create_singlethread_workqueue success\n", __func__);
+
+	retval = pci_request_regions(board_dat->pdev, KBUILD_MODNAME);
+	if (retval != 0) {
+		dev_err(&board_dat->pdev->dev,
+			"%s request_region failed\n", __func__);
+		goto err_return;
+	}
+
+	board_dat->pci_req_sts = true;
+
+	io_remap_addr = pci_iomap(board_dat->pdev, 1, 0);
+
+	if (io_remap_addr == 0) {
+		dev_err(&board_dat->pdev->dev,
+			"%s pci_iomap failed\n", __func__);
+		retval = -ENOMEM;
+		goto err_return;
+	}
+
+	/* calculate base address for all channels */
+	board_dat->data->io_remap_addr = io_remap_addr;
+
+	/* reset PCH SPI h/w */
+	pch_spi_reset(board_dat->data->master);
+	dev_dbg(&board_dat->pdev->dev,
+		"%s pch_spi_reset invoked successfully\n", __func__);
+
+	/* register IRQ */
+	retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
+			 IRQF_SHARED, KBUILD_MODNAME, (void *)board_dat);
+	if (retval != 0) {
+		dev_err(&board_dat->pdev->dev,
+			"%s request_irq failed\n", __func__);
+		goto err_return;
+	}
+
+	dev_dbg(&board_dat->pdev->dev, "%s request_irq returned=%d\n",
+		__func__, retval);
+
+	board_dat->irq_reg_sts = true;
+	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);
+	}
+
+	dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval);
+
+	return retval;
+}
+
+static int pch_spi_check_request_pending(struct pch_spi_board_data *board_dat)
+{
+	int sts;
+	u16 count;
+
+	count = 500;
+	spin_lock(&(board_dat->data->lock));
+	board_dat->data->status = STATUS_EXITING;
+
+	while ((list_empty(&(board_dat->data->queue)) == 0) &&
+	       (--count)) {
+		dev_dbg(&board_dat->pdev->dev,
+			"%s :queue not empty\n", __func__);
+		spin_unlock(&(board_dat->data->lock));
+		msleep(PCH_SLEEP_TIME);
+		spin_lock(&(board_dat->data->lock));
+	}
+
+	spin_unlock(&(board_dat->data->lock));
+
+	if (count) {
+		sts = 0;
+		dev_dbg(&board_dat->pdev->dev, "%s :queue empty\n", __func__);
+	} else {
+		sts = -EBUSY;
+	}
+
+	dev_dbg(&board_dat->pdev->dev, "%s : EXIT=%d\n", __func__, sts);
+
+	return sts;
+}
+
+static int pch_spi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+
+	struct spi_master *master;
+
+	struct pch_spi_board_data *board_dat;
+	int retval;
+
+	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+	/* allocate memory for private data */
+	board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL);
+	if (board_dat == NULL) {
+		dev_err(&pdev->dev,
+			" %s memory allocation for private data failed\n",
+			__func__);
+		retval = -ENOMEM;
+		goto err_kmalloc;
+	}
+
+	dev_dbg(&pdev->dev,
+		"%s memory allocation for private data success\n", __func__);
+
+	/* enable PCI device */
+	retval = pci_enable_device(pdev);
+	if (retval != 0) {
+		dev_err(&pdev->dev, "%s pci_enable_device FAILED\n", __func__);
+
+		goto err_pci_en_device;
+	}
+
+	dev_dbg(&pdev->dev, "%s pci_enable_device returned=%d\n",
+		__func__, retval);
+
+	board_dat->pdev = pdev;
+
+	/* alllocate memory for SPI master */
+	master = spi_alloc_master(&pdev->dev, sizeof(struct pch_spi_data));
+	if (master == NULL) {
+		retval = -ENOMEM;
+		dev_err(&pdev->dev, "%s Fail.\n", __func__);
+		goto err_spi_alloc_master;
+	}
+
+	dev_dbg(&pdev->dev,
+		"%s spi_alloc_master returned non NULL\n", __func__);
+
+	/* initialize members of SPI master */
+	master->bus_num = -1;
+	master->num_chipselect = PCH_MAX_CS;
+	master->setup = pch_spi_setup;
+	master->transfer = pch_spi_transfer;
+	dev_dbg(&pdev->dev,
+		"%s transfer member of SPI master initialized\n", __func__);
+
+	board_dat->data = spi_master_get_devdata(master);
+
+	board_dat->data->master = master;
+	board_dat->data->n_curnt_chip = 255;
+	board_dat->data->board_dat = board_dat;
+
+	/* allocate resources for PCH SPI */
+	retval = pch_spi_get_resources(board_dat);
+	if (retval != 0) {
+		dev_err(&pdev->dev, "%s fail(retval=%d)\n",
+			__func__, retval);
+		goto err_spi_get_resources;
+	}
+
+	dev_dbg(&pdev->dev, "%s pch_spi_get_resources returned=%d\n",
+		__func__, retval);
+
+	/* save private data in dev */
+	pci_set_drvdata(pdev, (void *)board_dat);
+	dev_dbg(&pdev->dev, "%s invoked pci_set_drvdata\n", __func__);
+
+	/* set master mode */
+	pch_spi_set_master_mode(master);
+	dev_dbg(&pdev->dev,
+		"%s invoked pch_spi_set_master_mode\n", __func__);
+
+	/* Register the controller with the SPI core. */
+	retval = spi_register_master(master);
+	if (retval != 0) {
+		dev_err(&pdev->dev,
+			"%s spi_register_master FAILED\n", __func__);
+		goto err_spi_reg_master;
+	}
+
+	dev_dbg(&pdev->dev, "%s spi_register_master returned=%d\n",
+		__func__, retval);
+
+
+	return 0;
+
+err_spi_reg_master:
+	spi_unregister_master(master);
+err_spi_get_resources:
+err_spi_alloc_master:
+	spi_master_put(master);
+	pci_disable_device(pdev);
+err_pci_en_device:
+	kfree(board_dat);
+err_kmalloc:
+	return retval;
+}
+
+static void pch_spi_remove(struct pci_dev *pdev)
+{
+	struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
+
+	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+	if (!board_dat) {
+		dev_err(&pdev->dev,
+			"%s pci_get_drvdata returned NULL\n", __func__);
+		return;
+	}
+
+	/* check for any pending messages */
+	if ((-EBUSY) == pch_spi_check_request_pending(board_dat)) {
+		dev_dbg(&pdev->dev,
+			"%s pch_spi_check_request_pending returned"
+			" EBUSY\n", __func__);
+		/* no need to take any particular action; proceed with remove
+		even though queue is not empty */
+	}
+
+	/* Free resources allocated for PCH SPI */
+	pch_spi_free_resources(board_dat);
+
+	/* Unregister SPI master */
+	spi_unregister_master(board_dat->data->master);
+
+	/* free memory for private data */
+	kfree(board_dat);
+
+	pci_set_drvdata(pdev, NULL);
+
+	/* disable PCI device */
+	pci_disable_device(pdev);
+
+	dev_dbg(&pdev->dev, "%s invoked pci_disable_device\n", __func__);
+}
+
+#ifdef CONFIG_PM
+static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+	u8 count;
+	int retval;
+
+	struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
+
+	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+	if (!board_dat) {
+		dev_err(&pdev->dev,
+			"%s pci_get_drvdata returned NULL\n", __func__);
+		return -EFAULT;
+	}
+
+	retval = 0;
+	board_dat->suspend_sts = true;
+
+	/* check if the current message is processed:
+	   Only after thats done the transfer will be suspended */
+	count = 255;
+	while ((--count) > 0) {
+		if (!(board_dat->data->bcurrent_msg_processing)) {
+			dev_dbg(&pdev->dev, "%s board_dat->data->bCurrent_"
+				"msg_processing = false\n", __func__);
+			break;
+		} else {
+			dev_dbg(&pdev->dev, "%s board_dat->data->bCurrent_msg_"
+				"processing = true\n", __func__);
+		}
+		msleep(PCH_SLEEP_TIME);
+	}
+
+	/* Free IRQ */
+	if (board_dat->irq_reg_sts) {
+		/* disable all interrupts */
+		pch_spi_disable_interrupts(board_dat->data->master, PCH_ALL);
+		pch_spi_reset(board_dat->data->master);
+		dev_dbg(&pdev->dev,
+			"%s pch_spi_disable_interrupts invoked successfully\n",
+			__func__);
+
+		free_irq(board_dat->pdev->irq, (void *)board_dat);
+
+		board_dat->irq_reg_sts = false;
+		dev_dbg(&pdev->dev,
+			"%s free_irq invoked successfully.\n", __func__);
+	}
+
+	/* save config space */
+	retval = pci_save_state(pdev);
+
+	if (retval == 0) {
+		dev_dbg(&pdev->dev, "%s pci_save_state returned=%d\n",
+			__func__, retval);
+		/* disable PM notifications */
+		pci_enable_wake(pdev, PCI_D3hot, 0);
+		dev_dbg(&pdev->dev,
+			"%s pci_enable_wake invoked successfully\n", __func__);
+		/* disable PCI device */
+		pci_disable_device(pdev);
+		dev_dbg(&pdev->dev,
+			"%s pci_disable_device invoked successfully\n",
+			__func__);
+		/* move device to D3hot  state */
+		pci_set_power_state(pdev, PCI_D3hot);
+		dev_dbg(&pdev->dev,
+			"%s pci_set_power_state invoked successfully\n",
+			__func__);
+	} else {
+		dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__);
+	}
+
+	dev_dbg(&pdev->dev, "%s return=%d\n", __func__, retval);
+
+	return retval;
+}
+
+static int pch_spi_resume(struct pci_dev *pdev)
+{
+	int retval;
+
+	struct pch_spi_board_data *board = pci_get_drvdata(pdev);
+	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+	if (!board) {
+		dev_err(&pdev->dev,
+			"%s pci_get_drvdata returned NULL\n", __func__);
+		return -EFAULT;
+	}
+
+	/* move device to DO power state */
+	pci_set_power_state(pdev, PCI_D0);
+
+	/* restore state */
+	pci_restore_state(pdev);
+
+	retval = pci_enable_device(pdev);
+	if (retval < 0) {
+		dev_err(&pdev->dev,
+			"%s pci_enable_device failed\n", __func__);
+	} else {
+		/* disable PM notifications */
+		pci_enable_wake(pdev, PCI_D3hot, 0);
+
+		/* register IRQ handler */
+		if (!(board->irq_reg_sts)) {
+			/* register IRQ */
+			retval = request_irq(board->pdev->irq, pch_spi_handler,
+					     IRQF_SHARED, KBUILD_MODNAME,
+					     board);
+			if (retval < 0) {
+				dev_err(&pdev->dev,
+					"%s request_irq failed\n", __func__);
+				return retval;
+			}
+			board->irq_reg_sts = true;
+
+			/* reset PCH SPI h/w */
+			pch_spi_reset(board->data->master);
+			pch_spi_set_master_mode(board->data->master);
+
+			/* set suspend status to false */
+			board->suspend_sts = false;
+
+		}
+	}
+
+	dev_dbg(&pdev->dev, "%s returning=%d\n", __func__, retval);
+
+	return retval;
+}
+#else
+#define pch_spi_suspend NULL
+#define pch_spi_resume NULL
+
+#endif
+
+static struct pci_driver pch_spi_pcidev = {
+	.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)
+{
+	return pci_register_driver(&pch_spi_pcidev);
+}
+module_init(pch_spi_init);
+
+
+static void __exit pch_spi_exit(void)
+{
+	pci_unregister_driver(&pch_spi_pcidev);
+}
+module_exit(pch_spi_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("PCH SPI PCI Driver");