Initial import

1 files changed, 880 insertions, 0 deletions

diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
new file mode 100644
index 000000000..80d245ac8
--- /dev/null
+++ b/drivers/spi/spi-fsl-espi.c
@@ -0,0 +1,880 @@
+/*
+ * Freescale eSPI controller driver.
+ *
+ * Copyright 2010 Freescale Semiconductor, Inc.
+ *
+ * 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;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/fsl_devices.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <sysdev/fsl_soc.h>
+
+#include "spi-fsl-lib.h"
+
+/* eSPI Controller registers */
+struct fsl_espi_reg {
+	__be32 mode;		/* 0x000 - eSPI mode register */
+	__be32 event;		/* 0x004 - eSPI event register */
+	__be32 mask;		/* 0x008 - eSPI mask register */
+	__be32 command;		/* 0x00c - eSPI command register */
+	__be32 transmit;	/* 0x010 - eSPI transmit FIFO access register*/
+	__be32 receive;		/* 0x014 - eSPI receive FIFO access register*/
+	u8 res[8];		/* 0x018 - 0x01c reserved */
+	__be32 csmode[4];	/* 0x020 - 0x02c eSPI cs mode register */
+};
+
+struct fsl_espi_transfer {
+	const void *tx_buf;
+	void *rx_buf;
+	unsigned len;
+	unsigned n_tx;
+	unsigned n_rx;
+	unsigned actual_length;
+	int status;
+};
+
+/* eSPI Controller mode register definitions */
+#define SPMODE_ENABLE		(1 << 31)
+#define SPMODE_LOOP		(1 << 30)
+#define SPMODE_TXTHR(x)		((x) << 8)
+#define SPMODE_RXTHR(x)		((x) << 0)
+
+/* eSPI Controller CS mode register definitions */
+#define CSMODE_CI_INACTIVEHIGH	(1 << 31)
+#define CSMODE_CP_BEGIN_EDGECLK	(1 << 30)
+#define CSMODE_REV		(1 << 29)
+#define CSMODE_DIV16		(1 << 28)
+#define CSMODE_PM(x)		((x) << 24)
+#define CSMODE_POL_1		(1 << 20)
+#define CSMODE_LEN(x)		((x) << 16)
+#define CSMODE_BEF(x)		((x) << 12)
+#define CSMODE_AFT(x)		((x) << 8)
+#define CSMODE_CG(x)		((x) << 3)
+
+/* Default mode/csmode for eSPI controller */
+#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(3))
+#define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
+		| CSMODE_AFT(0) | CSMODE_CG(1))
+
+/* SPIE register values */
+#define	SPIE_NE		0x00000200	/* Not empty */
+#define	SPIE_NF		0x00000100	/* Not full */
+
+/* SPIM register values */
+#define	SPIM_NE		0x00000200	/* Not empty */
+#define	SPIM_NF		0x00000100	/* Not full */
+#define SPIE_RXCNT(reg)     ((reg >> 24) & 0x3F)
+#define SPIE_TXCNT(reg)     ((reg >> 16) & 0x3F)
+
+/* SPCOM register values */
+#define SPCOM_CS(x)		((x) << 30)
+#define SPCOM_TRANLEN(x)	((x) << 0)
+#define	SPCOM_TRANLEN_MAX	0xFFFF	/* Max transaction length */
+
+static void fsl_espi_change_mode(struct spi_device *spi)
+{
+	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+	struct spi_mpc8xxx_cs *cs = spi->controller_state;
+	struct fsl_espi_reg *reg_base = mspi->reg_base;
+	__be32 __iomem *mode = &reg_base->csmode[spi->chip_select];
+	__be32 __iomem *espi_mode = &reg_base->mode;
+	u32 tmp;
+	unsigned long flags;
+
+	/* Turn off IRQs locally to minimize time that SPI is disabled. */
+	local_irq_save(flags);
+
+	/* Turn off SPI unit prior changing mode */
+	tmp = mpc8xxx_spi_read_reg(espi_mode);
+	mpc8xxx_spi_write_reg(espi_mode, tmp & ~SPMODE_ENABLE);
+	mpc8xxx_spi_write_reg(mode, cs->hw_mode);
+	mpc8xxx_spi_write_reg(espi_mode, tmp);
+
+	local_irq_restore(flags);
+}
+
+static u32 fsl_espi_tx_buf_lsb(struct mpc8xxx_spi *mpc8xxx_spi)
+{
+	u32 data;
+	u16 data_h;
+	u16 data_l;
+	const u32 *tx = mpc8xxx_spi->tx;
+
+	if (!tx)
+		return 0;
+
+	data = *tx++ << mpc8xxx_spi->tx_shift;
+	data_l = data & 0xffff;
+	data_h = (data >> 16) & 0xffff;
+	swab16s(&data_l);
+	swab16s(&data_h);
+	data = data_h | data_l;
+
+	mpc8xxx_spi->tx = tx;
+	return data;
+}
+
+static int fsl_espi_setup_transfer(struct spi_device *spi,
+					struct spi_transfer *t)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+	int bits_per_word = 0;
+	u8 pm;
+	u32 hz = 0;
+	struct spi_mpc8xxx_cs *cs = spi->controller_state;
+
+	if (t) {
+		bits_per_word = t->bits_per_word;
+		hz = t->speed_hz;
+	}
+
+	/* spi_transfer level calls that work per-word */
+	if (!bits_per_word)
+		bits_per_word = spi->bits_per_word;
+
+	if (!hz)
+		hz = spi->max_speed_hz;
+
+	cs->rx_shift = 0;
+	cs->tx_shift = 0;
+	cs->get_rx = mpc8xxx_spi_rx_buf_u32;
+	cs->get_tx = mpc8xxx_spi_tx_buf_u32;
+	if (bits_per_word <= 8) {
+		cs->rx_shift = 8 - bits_per_word;
+	} else {
+		cs->rx_shift = 16 - bits_per_word;
+		if (spi->mode & SPI_LSB_FIRST)
+			cs->get_tx = fsl_espi_tx_buf_lsb;
+	}
+
+	mpc8xxx_spi->rx_shift = cs->rx_shift;
+	mpc8xxx_spi->tx_shift = cs->tx_shift;
+	mpc8xxx_spi->get_rx = cs->get_rx;
+	mpc8xxx_spi->get_tx = cs->get_tx;
+
+	bits_per_word = bits_per_word - 1;
+
+	/* mask out bits we are going to set */
+	cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF));
+
+	cs->hw_mode |= CSMODE_LEN(bits_per_word);
+
+	if ((mpc8xxx_spi->spibrg / hz) > 64) {
+		cs->hw_mode |= CSMODE_DIV16;
+		pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 16 * 4);
+
+		WARN_ONCE(pm > 33, "%s: Requested speed is too low: %d Hz. "
+			  "Will use %d Hz instead.\n", dev_name(&spi->dev),
+				hz, mpc8xxx_spi->spibrg / (4 * 16 * (32 + 1)));
+		if (pm > 33)
+			pm = 33;
+	} else {
+		pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 4);
+	}
+	if (pm)
+		pm--;
+	if (pm < 2)
+		pm = 2;
+
+	cs->hw_mode |= CSMODE_PM(pm);
+
+	fsl_espi_change_mode(spi);
+	return 0;
+}
+
+static int fsl_espi_cpu_bufs(struct mpc8xxx_spi *mspi, struct spi_transfer *t,
+		unsigned int len)
+{
+	u32 word;
+	struct fsl_espi_reg *reg_base = mspi->reg_base;
+
+	mspi->count = len;
+
+	/* enable rx ints */
+	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
+
+	/* transmit word */
+	word = mspi->get_tx(mspi);
+	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
+
+	return 0;
+}
+
+static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+	struct fsl_espi_reg *reg_base = mpc8xxx_spi->reg_base;
+	unsigned int len = t->len;
+	int ret;
+
+	mpc8xxx_spi->len = t->len;
+	len = roundup(len, 4) / 4;
+
+	mpc8xxx_spi->tx = t->tx_buf;
+	mpc8xxx_spi->rx = t->rx_buf;
+
+	reinit_completion(&mpc8xxx_spi->done);
+
+	/* Set SPCOM[CS] and SPCOM[TRANLEN] field */
+	if ((t->len - 1) > SPCOM_TRANLEN_MAX) {
+		dev_err(mpc8xxx_spi->dev, "Transaction length (%d)"
+				" beyond the SPCOM[TRANLEN] field\n", t->len);
+		return -EINVAL;
+	}
+	mpc8xxx_spi_write_reg(&reg_base->command,
+		(SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1)));
+
+	ret = fsl_espi_cpu_bufs(mpc8xxx_spi, t, len);
+	if (ret)
+		return ret;
+
+	wait_for_completion(&mpc8xxx_spi->done);
+
+	/* disable rx ints */
+	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
+
+	return mpc8xxx_spi->count;
+}
+
+static inline void fsl_espi_addr2cmd(unsigned int addr, u8 *cmd)
+{
+	if (cmd) {
+		cmd[1] = (u8)(addr >> 16);
+		cmd[2] = (u8)(addr >> 8);
+		cmd[3] = (u8)(addr >> 0);
+	}
+}
+
+static inline unsigned int fsl_espi_cmd2addr(u8 *cmd)
+{
+	if (cmd)
+		return cmd[1] << 16 | cmd[2] << 8 | cmd[3] << 0;
+
+	return 0;
+}
+
+static void fsl_espi_do_trans(struct spi_message *m,
+				struct fsl_espi_transfer *tr)
+{
+	struct spi_device *spi = m->spi;
+	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+	struct fsl_espi_transfer *espi_trans = tr;
+	struct spi_message message;
+	struct spi_transfer *t, *first, trans;
+	int status = 0;
+
+	spi_message_init(&message);
+	memset(&trans, 0, sizeof(trans));
+
+	first = list_first_entry(&m->transfers, struct spi_transfer,
+			transfer_list);
+	list_for_each_entry(t, &m->transfers, transfer_list) {
+		if ((first->bits_per_word != t->bits_per_word) ||
+			(first->speed_hz != t->speed_hz)) {
+			espi_trans->status = -EINVAL;
+			dev_err(mspi->dev,
+				"bits_per_word/speed_hz should be same for the same SPI transfer\n");
+			return;
+		}
+
+		trans.speed_hz = t->speed_hz;
+		trans.bits_per_word = t->bits_per_word;
+		trans.delay_usecs = max(first->delay_usecs, t->delay_usecs);
+	}
+
+	trans.len = espi_trans->len;
+	trans.tx_buf = espi_trans->tx_buf;
+	trans.rx_buf = espi_trans->rx_buf;
+	spi_message_add_tail(&trans, &message);
+
+	list_for_each_entry(t, &message.transfers, transfer_list) {
+		if (t->bits_per_word || t->speed_hz) {
+			status = -EINVAL;
+
+			status = fsl_espi_setup_transfer(spi, t);
+			if (status < 0)
+				break;
+		}
+
+		if (t->len)
+			status = fsl_espi_bufs(spi, t);
+
+		if (status) {
+			status = -EMSGSIZE;
+			break;
+		}
+
+		if (t->delay_usecs)
+			udelay(t->delay_usecs);
+	}
+
+	espi_trans->status = status;
+	fsl_espi_setup_transfer(spi, NULL);
+}
+
+static void fsl_espi_cmd_trans(struct spi_message *m,
+				struct fsl_espi_transfer *trans, u8 *rx_buff)
+{
+	struct spi_transfer *t;
+	u8 *local_buf;
+	int i = 0;
+	struct fsl_espi_transfer *espi_trans = trans;
+
+	local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
+	if (!local_buf) {
+		espi_trans->status = -ENOMEM;
+		return;
+	}
+
+	list_for_each_entry(t, &m->transfers, transfer_list) {
+		if (t->tx_buf) {
+			memcpy(local_buf + i, t->tx_buf, t->len);
+			i += t->len;
+		}
+	}
+
+	espi_trans->tx_buf = local_buf;
+	espi_trans->rx_buf = local_buf;
+	fsl_espi_do_trans(m, espi_trans);
+
+	espi_trans->actual_length = espi_trans->len;
+	kfree(local_buf);
+}
+
+static void fsl_espi_rw_trans(struct spi_message *m,
+				struct fsl_espi_transfer *trans, u8 *rx_buff)
+{
+	struct fsl_espi_transfer *espi_trans = trans;
+	unsigned int total_len = espi_trans->len;
+	struct spi_transfer *t;
+	u8 *local_buf;
+	u8 *rx_buf = rx_buff;
+	unsigned int trans_len;
+	unsigned int addr;
+	unsigned int tx_only;
+	unsigned int rx_pos = 0;
+	unsigned int pos;
+	int i, loop;
+
+	local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
+	if (!local_buf) {
+		espi_trans->status = -ENOMEM;
+		return;
+	}
+
+	for (pos = 0, loop = 0; pos < total_len; pos += trans_len, loop++) {
+		trans_len = total_len - pos;
+
+		i = 0;
+		tx_only = 0;
+		list_for_each_entry(t, &m->transfers, transfer_list) {
+			if (t->tx_buf) {
+				memcpy(local_buf + i, t->tx_buf, t->len);
+				i += t->len;
+				if (!t->rx_buf)
+					tx_only += t->len;
+			}
+		}
+
+		/* Add additional TX bytes to compensate SPCOM_TRANLEN_MAX */
+		if (loop > 0)
+			trans_len += tx_only;
+
+		if (trans_len > SPCOM_TRANLEN_MAX)
+			trans_len = SPCOM_TRANLEN_MAX;
+
+		/* Update device offset */
+		if (pos > 0) {
+			addr = fsl_espi_cmd2addr(local_buf);
+			addr += rx_pos;
+			fsl_espi_addr2cmd(addr, local_buf);
+		}
+
+		espi_trans->len = trans_len;
+		espi_trans->tx_buf = local_buf;
+		espi_trans->rx_buf = local_buf;
+		fsl_espi_do_trans(m, espi_trans);
+
+		/* If there is at least one RX byte then copy it to rx_buf */
+		if (tx_only < SPCOM_TRANLEN_MAX)
+			memcpy(rx_buf + rx_pos, espi_trans->rx_buf + tx_only,
+					trans_len - tx_only);
+
+		rx_pos += trans_len - tx_only;
+
+		if (loop > 0)
+			espi_trans->actual_length += espi_trans->len - tx_only;
+		else
+			espi_trans->actual_length += espi_trans->len;
+	}
+
+	kfree(local_buf);
+}
+
+static int fsl_espi_do_one_msg(struct spi_master *master,
+			       struct spi_message *m)
+{
+	struct spi_transfer *t;
+	u8 *rx_buf = NULL;
+	unsigned int n_tx = 0;
+	unsigned int n_rx = 0;
+	unsigned int xfer_len = 0;
+	struct fsl_espi_transfer espi_trans;
+
+	list_for_each_entry(t, &m->transfers, transfer_list) {
+		if (t->tx_buf)
+			n_tx += t->len;
+		if (t->rx_buf) {
+			n_rx += t->len;
+			rx_buf = t->rx_buf;
+		}
+		if ((t->tx_buf) || (t->rx_buf))
+			xfer_len += t->len;
+	}
+
+	espi_trans.n_tx = n_tx;
+	espi_trans.n_rx = n_rx;
+	espi_trans.len = xfer_len;
+	espi_trans.actual_length = 0;
+	espi_trans.status = 0;
+
+	if (!rx_buf)
+		fsl_espi_cmd_trans(m, &espi_trans, NULL);
+	else
+		fsl_espi_rw_trans(m, &espi_trans, rx_buf);
+
+	m->actual_length = espi_trans.actual_length;
+	m->status = espi_trans.status;
+	spi_finalize_current_message(master);
+	return 0;
+}
+
+static int fsl_espi_setup(struct spi_device *spi)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi;
+	struct fsl_espi_reg *reg_base;
+	int retval;
+	u32 hw_mode;
+	u32 loop_mode;
+	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
+
+	if (!spi->max_speed_hz)
+		return -EINVAL;
+
+	if (!cs) {
+		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
+		if (!cs)
+			return -ENOMEM;
+		spi_set_ctldata(spi, cs);
+	}
+
+	mpc8xxx_spi = spi_master_get_devdata(spi->master);
+	reg_base = mpc8xxx_spi->reg_base;
+
+	hw_mode = cs->hw_mode; /* Save original settings */
+	cs->hw_mode = mpc8xxx_spi_read_reg(
+			&reg_base->csmode[spi->chip_select]);
+	/* mask out bits we are going to set */
+	cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
+			 | CSMODE_REV);
+
+	if (spi->mode & SPI_CPHA)
+		cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK;
+	if (spi->mode & SPI_CPOL)
+		cs->hw_mode |= CSMODE_CI_INACTIVEHIGH;
+	if (!(spi->mode & SPI_LSB_FIRST))
+		cs->hw_mode |= CSMODE_REV;
+
+	/* Handle the loop mode */
+	loop_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
+	loop_mode &= ~SPMODE_LOOP;
+	if (spi->mode & SPI_LOOP)
+		loop_mode |= SPMODE_LOOP;
+	mpc8xxx_spi_write_reg(&reg_base->mode, loop_mode);
+
+	retval = fsl_espi_setup_transfer(spi, NULL);
+	if (retval < 0) {
+		cs->hw_mode = hw_mode; /* Restore settings */
+		return retval;
+	}
+	return 0;
+}
+
+static void fsl_espi_cleanup(struct spi_device *spi)
+{
+	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
+
+	kfree(cs);
+	spi_set_ctldata(spi, NULL);
+}
+
+void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
+{
+	struct fsl_espi_reg *reg_base = mspi->reg_base;
+
+	/* We need handle RX first */
+	if (events & SPIE_NE) {
+		u32 rx_data, tmp;
+		u8 rx_data_8;
+
+		/* Spin until RX is done */
+		while (SPIE_RXCNT(events) < min(4, mspi->len)) {
+			cpu_relax();
+			events = mpc8xxx_spi_read_reg(&reg_base->event);
+		}
+
+		if (mspi->len >= 4) {
+			rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
+		} else {
+			tmp = mspi->len;
+			rx_data = 0;
+			while (tmp--) {
+				rx_data_8 = in_8((u8 *)&reg_base->receive);
+				rx_data |= (rx_data_8 << (tmp * 8));
+			}
+
+			rx_data <<= (4 - mspi->len) * 8;
+		}
+
+		mspi->len -= 4;
+
+		if (mspi->rx)
+			mspi->get_rx(rx_data, mspi);
+	}
+
+	if (!(events & SPIE_NF)) {
+		int ret;
+
+		/* spin until TX is done */
+		ret = spin_event_timeout(((events = mpc8xxx_spi_read_reg(
+				&reg_base->event)) & SPIE_NF) == 0, 1000, 0);
+		if (!ret) {
+			dev_err(mspi->dev, "tired waiting for SPIE_NF\n");
+			return;
+		}
+	}
+
+	/* Clear the events */
+	mpc8xxx_spi_write_reg(&reg_base->event, events);
+
+	mspi->count -= 1;
+	if (mspi->count) {
+		u32 word = mspi->get_tx(mspi);
+
+		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
+	} else {
+		complete(&mspi->done);
+	}
+}
+
+static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
+{
+	struct mpc8xxx_spi *mspi = context_data;
+	struct fsl_espi_reg *reg_base = mspi->reg_base;
+	irqreturn_t ret = IRQ_NONE;
+	u32 events;
+
+	/* Get interrupt events(tx/rx) */
+	events = mpc8xxx_spi_read_reg(&reg_base->event);
+	if (events)
+		ret = IRQ_HANDLED;
+
+	dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events);
+
+	fsl_espi_cpu_irq(mspi, events);
+
+	return ret;
+}
+
+static void fsl_espi_remove(struct mpc8xxx_spi *mspi)
+{
+	iounmap(mspi->reg_base);
+}
+
+static int fsl_espi_suspend(struct spi_master *master)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi;
+	struct fsl_espi_reg *reg_base;
+	u32 regval;
+
+	mpc8xxx_spi = spi_master_get_devdata(master);
+	reg_base = mpc8xxx_spi->reg_base;
+
+	regval = mpc8xxx_spi_read_reg(&reg_base->mode);
+	regval &= ~SPMODE_ENABLE;
+	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
+
+	return 0;
+}
+
+static int fsl_espi_resume(struct spi_master *master)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi;
+	struct fsl_espi_reg *reg_base;
+	u32 regval;
+
+	mpc8xxx_spi = spi_master_get_devdata(master);
+	reg_base = mpc8xxx_spi->reg_base;
+
+	regval = mpc8xxx_spi_read_reg(&reg_base->mode);
+	regval |= SPMODE_ENABLE;
+	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
+
+	return 0;
+}
+
+static struct spi_master * fsl_espi_probe(struct device *dev,
+		struct resource *mem, unsigned int irq)
+{
+	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
+	struct spi_master *master;
+	struct mpc8xxx_spi *mpc8xxx_spi;
+	struct fsl_espi_reg *reg_base;
+	struct device_node *nc;
+	const __be32 *prop;
+	u32 regval, csmode;
+	int i, len, ret = 0;
+
+	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
+	if (!master) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	dev_set_drvdata(dev, master);
+
+	mpc8xxx_spi_probe(dev, mem, irq);
+
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
+	master->setup = fsl_espi_setup;
+	master->cleanup = fsl_espi_cleanup;
+	master->transfer_one_message = fsl_espi_do_one_msg;
+	master->prepare_transfer_hardware = fsl_espi_resume;
+	master->unprepare_transfer_hardware = fsl_espi_suspend;
+
+	mpc8xxx_spi = spi_master_get_devdata(master);
+	mpc8xxx_spi->spi_remove = fsl_espi_remove;
+
+	mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
+	if (!mpc8xxx_spi->reg_base) {
+		ret = -ENOMEM;
+		goto err_probe;
+	}
+
+	reg_base = mpc8xxx_spi->reg_base;
+
+	/* Register for SPI Interrupt */
+	ret = request_irq(mpc8xxx_spi->irq, fsl_espi_irq,
+			  0, "fsl_espi", mpc8xxx_spi);
+	if (ret)
+		goto free_irq;
+
+	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
+		mpc8xxx_spi->rx_shift = 16;
+		mpc8xxx_spi->tx_shift = 24;
+	}
+
+	/* SPI controller initializations */
+	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
+	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
+	mpc8xxx_spi_write_reg(&reg_base->command, 0);
+	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
+
+	/* Init eSPI CS mode register */
+	for_each_available_child_of_node(master->dev.of_node, nc) {
+		/* get chip select */
+		prop = of_get_property(nc, "reg", &len);
+		if (!prop || len < sizeof(*prop))
+			continue;
+		i = be32_to_cpup(prop);
+		if (i < 0 || i >= pdata->max_chipselect)
+			continue;
+
+		csmode = CSMODE_INIT_VAL;
+		/* check if CSBEF is set in device tree */
+		prop = of_get_property(nc, "fsl,csbef", &len);
+		if (prop && len >= sizeof(*prop)) {
+			csmode &= ~(CSMODE_BEF(0xf));
+			csmode |= CSMODE_BEF(be32_to_cpup(prop));
+		}
+		/* check if CSAFT is set in device tree */
+		prop = of_get_property(nc, "fsl,csaft", &len);
+		if (prop && len >= sizeof(*prop)) {
+			csmode &= ~(CSMODE_AFT(0xf));
+			csmode |= CSMODE_AFT(be32_to_cpup(prop));
+		}
+		mpc8xxx_spi_write_reg(&reg_base->csmode[i], csmode);
+
+		dev_info(dev, "cs=%d, init_csmode=0x%x\n", i, csmode);
+	}
+
+	/* Enable SPI interface */
+	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
+
+	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
+
+	ret = spi_register_master(master);
+	if (ret < 0)
+		goto unreg_master;
+
+	dev_info(dev, "at 0x%p (irq = %d)\n", reg_base, mpc8xxx_spi->irq);
+
+	return master;
+
+unreg_master:
+	free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
+free_irq:
+	iounmap(mpc8xxx_spi->reg_base);
+err_probe:
+	spi_master_put(master);
+err:
+	return ERR_PTR(ret);
+}
+
+static int of_fsl_espi_get_chipselects(struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
+	const u32 *prop;
+	int len;
+
+	prop = of_get_property(np, "fsl,espi-num-chipselects", &len);
+	if (!prop || len < sizeof(*prop)) {
+		dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
+		return -EINVAL;
+	}
+
+	pdata->max_chipselect = *prop;
+	pdata->cs_control = NULL;
+
+	return 0;
+}
+
+static int of_fsl_espi_probe(struct platform_device *ofdev)
+{
+	struct device *dev = &ofdev->dev;
+	struct device_node *np = ofdev->dev.of_node;
+	struct spi_master *master;
+	struct resource mem;
+	unsigned int irq;
+	int ret = -ENOMEM;
+
+	ret = of_mpc8xxx_spi_probe(ofdev);
+	if (ret)
+		return ret;
+
+	ret = of_fsl_espi_get_chipselects(dev);
+	if (ret)
+		goto err;
+
+	ret = of_address_to_resource(np, 0, &mem);
+	if (ret)
+		goto err;
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (!irq) {
+		ret = -EINVAL;
+		goto err;
+	}
+
+	master = fsl_espi_probe(dev, &mem, irq);
+	if (IS_ERR(master)) {
+		ret = PTR_ERR(master);
+		goto err;
+	}
+
+	return 0;
+
+err:
+	return ret;
+}
+
+static int of_fsl_espi_remove(struct platform_device *dev)
+{
+	return mpc8xxx_spi_remove(&dev->dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int of_fsl_espi_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	int ret;
+
+	ret = spi_master_suspend(master);
+	if (ret) {
+		dev_warn(dev, "cannot suspend master\n");
+		return ret;
+	}
+
+	return fsl_espi_suspend(master);
+}
+
+static int of_fsl_espi_resume(struct device *dev)
+{
+	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct mpc8xxx_spi *mpc8xxx_spi;
+	struct fsl_espi_reg *reg_base;
+	u32 regval;
+	int i;
+
+	mpc8xxx_spi = spi_master_get_devdata(master);
+	reg_base = mpc8xxx_spi->reg_base;
+
+	/* SPI controller initializations */
+	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
+	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
+	mpc8xxx_spi_write_reg(&reg_base->command, 0);
+	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
+
+	/* Init eSPI CS mode register */
+	for (i = 0; i < pdata->max_chipselect; i++)
+		mpc8xxx_spi_write_reg(&reg_base->csmode[i], CSMODE_INIT_VAL);
+
+	/* Enable SPI interface */
+	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
+
+	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
+
+	return spi_master_resume(master);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops espi_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(of_fsl_espi_suspend, of_fsl_espi_resume)
+};
+
+static const struct of_device_id of_fsl_espi_match[] = {
+	{ .compatible = "fsl,mpc8536-espi" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, of_fsl_espi_match);
+
+static struct platform_driver fsl_espi_driver = {
+	.driver = {
+		.name = "fsl_espi",
+		.of_match_table = of_fsl_espi_match,
+		.pm = &espi_pm,
+	},
+	.probe		= of_fsl_espi_probe,
+	.remove		= of_fsl_espi_remove,
+};
+module_platform_driver(fsl_espi_driver);
+
+MODULE_AUTHOR("Mingkai Hu");
+MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
+MODULE_LICENSE("GPL");